oEPA

United States	Office of Water	EPA-820-D-24-003

Environmental Protection	4304T	December 2024

Agency

DRAFT

Supporting Information for Comparison of OPP Aquatic Life Benchmarks,
OW Aquatic Life Criteria and Alternative Criteria-Related Approaches
When Data are Insufficient to Develop Aquatic Life Criteria

Data supporting the analyses in
Draft Comparison of Aquatic Life Protective Values Developed for Pesticides under the
Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA)
and the Clean Water Act (CWA)

Prepared by:
U.S. Environmental Protection Agency
Office of Water & Office of Pesticide Programs
Washington, DC

December 2024


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Table of Contents

Table of Contents	ii

1 Insecticides	1

1.1	Data-Rich Pesticides	1

1.1.1	Comparison of Aquatic Life Toxicity Values for Carbaryl: Data Sources and
Considerations	1

1.1.2	Comparison of Aquatic Life Toxicity Values for Methomyl: Data Sources and
Considerations	26

1.1.3	Comparison of Aquatic Life Toxicity Values for Propoxur: Data Sources and
Considerations	35

1.1.4	Comparison of Aquatic Life Toxicity Values for Malathion: Data Sources and
Considerations	42

1.1.5	Comparison of Aquatic Life Toxicity Values for Diazinon: Data Sources and
Considerations	65

1.1.6	Comparison of Aquatic Life Toxicity Values for Chlorpyrifos: Data Sources and
Considerations	83

1.1.7	Comparison of Aquatic Life Toxicity Values for Dichlorvos: Data Sources and
Considerations	95

1.1.8	Comparison of Aquatic Life Toxicity Values for Acrolein: Data Sources and
Considerations	101

1.2	Data-Limited Pesticides	106

1.2.1	Comparison of Aquatic Life Toxicity Values for Oxamyl: Data Sources and
Considerations	106

1.2.2	Comparison of Aquatic Life Toxicity Values for Acephate: Data Sources and
Considerations	114

1.2.3	Comparison of Aquatic Life Toxicity Values for Dimethoate: Data Sources and
Considerations	124

1.2.4	Comparison of Aquatic Life Toxicity Values for Phosmet: Data Sources and
Considerations	132

1.2.5	Comparison of Aquatic Life Toxicity Values for Terbufos: Data Sources and
Considerations	140

1.3	Data Insufficient Pesticides	150

1.3.1	Comparison of Aquatic Life Toxicity Values for Methamidophos: Data Sources
and Considerations	150

1.3.2	Comparison of Aquatic Life Toxicity Values for Profenofos: Data Sources and
Considerations	159

1.3.3	Comparison of Aquatic Life Toxicity Values for Fenpropathrin: Data Sources

and Considerations	168

1.3.4	Comparison of Aquatic Life Toxicity Values for Fenbutatin Oxide: Data Sources
and Considerations	176

1.3.5	Comparison of Aquatic Life Toxicity Values for Methoxyfenozide: Data Sources
and Considerations	184

1.3.6	Comparison of Aquatic Life Toxicity Values for Norflurazon: Data Sources and
Considerations	192

1.3.7	Comparison of Aquatic Life Toxicity Values for Propargite: Data Sources and
Considerations	199

ii


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1.3.8 Comparison of Aquatic Life Toxicity Values for Pyridaben: Data Sources and

Considerations	206

2 Herbicides	213

2.1 Data-Rich Herbicides	213

2.1.1	Comparison of Aquatic Life Toxicity Values for Atrazine: Data Sources and
Considerations	213

2.1.2	Comparison of Aquatic Life Toxicity Values for Propazine: Data Sources and
Considerations	230

2.1.3	Comparison of Aquatic Life Toxicity Values for Simazine: Data Sources and
Considerations	240

2.1.4	Comparison of Aquatic Life Toxicity Values for Bensulide: Data Sources and
Considerations	254

2.1.5	Comparison of Aquatic Life Toxicity Values for Glyphosate: Data Sources and
Considerations	265

in


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1 Insecticides

1.1 Data-Rich Pesticides

1.1.1 Comparison of Aquatic Life Toxicity Values for Carbaryl: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA) (U.S.EPA 2024) for carbaryl were obtained from Appendix A of the
2012 carbaryl criteria document, supplemented with additional data reported in Table L-6 of U.S.
EPA (2007), the OPP pesticide effects determination document that served as the basis for the
invertebrate OPP benchmark concentration.

1.1.1.1 Carbaryl Acute Toxicity Data

The EPA obtained acute data from the carbaryl Aquatic Life Criteria (ALC; 2012) and the OPP
pesticide effects determination value document (2007) (See Table 1). Table L-6 of Appendix L
in U.S. EPA (2007) included three LCsos that were not included in Appendix A of the 2012
carbaryl ALC. These were an LCso of 26 |ig/L for Gammarus fasciatus, an LCso of 8 |ig/L for
Gammarus pseudolimnaeus, and an LCso of 1,900 |ig/L for Procambarus sp. All three of these
LCsos were reported in Mayer and Ellersieck (1986). The G. fasciatus LC50 was not included in
Appendix A of the carbaryl ALC (U.S. EPA 2012) because the test chemical included excessive
solvent. The G. pseudolimnaeus LC50 was not included in Appendix A because it was a 48-hour
test, not the recommended 96-hour duration of a test for this species. The Procambarus sp. LC50
test was not used because no species was reported, and a more sensitive LC50 of 1,000 |ig/L was
available for the clearly specified P. clarkii.

The most sensitive species according to Table L-6 of U.S. EPA (2007) of the OPP pesticide
effects determination was the stonefly Pteronarcella badia, with an LC50 of 1.7 |ig/L. An LC50
of 1.7 |ig/L fori5, badia is reported in Mayer and Ellersieck (1986) and is the most sensitive
value in U.S. EPA (2007). This is one of four LCsos used to generate the P. badia Species Mean
Acute Value (SMAV) of 9.163 |ig/L in the 2012 carbaryl ALC.

The final dataset consists of 61 SMAVs and 47 Genus Mean Acute Values (GMAVs), including
26 invertebrate species representing 20 invertebrate genera. Ranked SMAVs and GMAVs for all
invertebrates included in this analysis are listed in Table 2 below.

1


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Table 1. Acute toxicity data of carbaryl to freshwater aquatic organisms.

(ATDR specifics OW minimum data requirements under the Guidelines )

OW
M l)K

(iroup11

Speck's

l.( 50/l.( 50
(fiii/l.)

SM.W

(iM.W

(flli/l.)

Reference

H

Oligochaete worm,
Lumbriculus variegatus

8,200

8,200

8,200

Bailey and Liu 1980

G

Snail (adult),
Aplexa hypnorum

>27,000

>27,000

>27,00

Phipps and Holcombe 1985

G

Mussel (juvenile; 1-2 d),
Anodonta imbecillis

23,700

24,632

24,632

Johnson etal. 1993

G

Mussel (juvenile; 7-10 d),
Anodonta imbecillis

25,600

Johnson etal. 1993

D

Cladoceran (<24 hr),
Ceriodaphnia dubia

3.06

5.958

5.958

Brooke 1990; 1991

D

Cladoceran (<12 hr),
Ceriodaphnia dubia

11.6

Oris et al. 1991

D

Cladoceran (adult; 2-2.5 mm),
Daphnia carinata

35

35



Santharam et al. 1976

D

Cladoceran (5 d),
Daphnia magna

7.2





Lakotaetal. 1981

D

Cladoceran (<24 hr),
Daphnia magna

1,900

29.658

18.80

Johnson etal. 1993

D

Cladoceran (<24 hr),
Daphnia magna

5.6

Sanders et al. 1983

D

Cladoceran (<24 hr),
Daphnia magna

10.1





Brooke 1991

D

Cladoceran (<24 hr),
Daphnia pulex

6.4

6.4



Sanders and Cope 1966

D

Cladoceran (<24 hr),
Simocephalus serrulatus

11





Mayer and Ellersieck 1986

D

Cladoceran (<24 hr),
Simocephalus serrulatus

8.1

8.781

8.781

Mayer and Ellersieck 1986

D

Cladoceran (<24 hr),
Simocephalus serrulatus

7.6





Sanders and Cope 1966

E

Mysid,

My sis relicta

230

230

230

Landrum and Dupuis 1990

E

Aquatic sowbug (mature),
Asellus brevicaudus

280

280

280

Johnson and Finley 1980;
Mayer and Ellersieck 1986

E

Amphipod (2 mo),
Gammarus lacustris

16

18.76



Sanders 1969

E

Amphipod (mature),
Gammarus lacustris

22



Johnson and Finley 1980;
Mayer and Ellersieck 1986

E

Amphipod,
Gammarus fasciatus

26

26



MRID 40098001; Mayer and
Ellersieck 1986

E

Amphipod,

Gammarus pseudolimnaeus

8



16.76

MRID 40098001; Mayer and
Ellersieck 1986

E

Amphipod,

Gammarus pseudolimnaeus

13

9.65



Woodward and Mauck 1980

E

Amphipod (mature),
Gammarus pseudolimnaeus

7



Woodward and Mauck 1980

E

Amphipod (mature),
Gammarus pseudolimnaeus

7.2





Woodward and Mauck 1980

2


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()\\
MIJR

(iroup11

Species

l.( 50/l.( 50
(Jlg/I.)

SMAY

(fm/i.)

(;\1AY

(flli/l.)

Reference

E

Amphipod (mature),
Gammarus pseudolimnaeus

16





Sanders et al. 1983

E

Amphipod (14 d),
Hyalella azteca

15.2

15.2

15.2

McNulty et al. 1999

E

Amphipod,
Pontoporeia hoyi

250

250

250

Landrum and Dupuis 1990

E

Crayfish (3-4 cm),
Cambarus bartoni

839.6

839.6

839.6

Simon 1982

E

Crayfish (3.9 g),
Orconectes immunis

2,870

2,870

2,462

Phipps and Holcombe 1985

E

Crayfish (5-8 cm; males),
Orconectes virilis

2,112

2,112

Simon 1982

E

Crayfish (15-38 g),
Procambarus clarkii

1,000

1,000

1,378

Andreu-Moliner et al. 1986

E

Crayfish,
Procambarus sp.

1,900

1,900

MRID 40098001; Mayer and
Ellersieck 1986

F

Stonefly (nymph),
Claassenia sabulosa

5.6

5.6

5.6

Sanders and Cope 1968

F

Stonefly (1st yr class),
Isogenus sp.

2.8

3.175

3.175

Mayer and Ellersieck 1986

F

Stonefly (1st yr class),
Isogenus sp.

3.6

Mayer and Ellersieck 1986

F

Stonefly (1st yr class; 15-20
mm),

Pteronarcella badia

1.7





Sanders and Cope 1968

F

Stonefly (1st yr class),
Pteronarcella badia

11

9.163

9.163

Woodward and Mauck 1980;
Mayer and Ellersieck 1986

F

Stonefly (1st yr class),
Pteronarcella badia

13





Woodward and Mauck 1980;
Mayer and Ellersieck 1986

F

Stonefly (1st yr class),
Pteronarcella badia

29





Woodward and Mauck 1980;
Mayer and Ellersieck 1986

F

Stonefly (1st yr class),
Pteronarcys californica

4.8

4.8

4.8

Sanders and Cope 1968

F

Stonefly (naiad),
Skwala sp.

3.6

3.6

3.6

Johnson and Finley 1980

F

Backswimmer (adult),
Notonecta undulata

200

200

200

Federle and Collins 1976

A

Apache trout (0.38-0.85 g),
Oncorhynchus apache

1,540

1,540



Dwyeretal. 1995

A

Coho salmon (2.7-4.1 g),
Oncorhynchus kisutch

997





Katz 1961

A

Coho salmon,
Oncorhynchus kisutch

764





Macek and McAllister 1970

A

Coho salmon (1.50 g),
Oncorhynchus kisutch

1,300

1,654

1,994

Post and Schroeder 1971

A

Coho salmon (1.0 g),
Oncorhynchus kisutch

4,340



Johnson and Finley 1980;
Mayer and Ellersieck 1986

A

Coho salmon (10.10 g),
Oncorhynchus kisutch

2,700





Mayer and Ellersieck 1986

A

Coho salmon (19.1 g),
Oncorhynchus kisutch

1,150





Mayer and Ellersieck 1986

3


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()\\
MIJR

(iroup11

Species

l.( 50/l.( 50
(Jlg/I.)

SMAY

(fm/i.)

(;\1AY

(flli/l.)

Reference

A

Coho salmon (4.6 g),
Oncorhynchus kisutch

2,400





Mayer and Ellersieck 1986

A

Coho salmon (5.1g),
Oncorhynchus kisutch

1,750

Mayer and Ellersieck 1986

A

Chinook salmon (fingerling),
Oncorhynchus tshawytscha

2,400

2,541

Johnson and Finley 1980;
Mayer and Ellersieck 1986

A

Chinook salmon (3.0 g),
Oncorhynchus tshawytscha

2,690

Phipps and Holcombe 1985;
1990

A

Cutthroat trout (0.37 g),
Oncorhynchus clarkii

1,500

3,300

Post and Schroeder 1971

A

Cutthroat trout (1.30 g),
Oncorhynchus clarkii

2,169

Post and Schroeder 1971

A

Cutthroat trout (0.5 g),
Oncorhynchus clarkii

7,100

Johnson and Finley 1980;
Mayer and Ellersieck 1986

A

Cutthroat trout (0.6 g),
Oncorhynchus clarkii

6,000

Woodward and Mauck 1980;
Mayer and Ellersieck 1986

A

Cutthroat trout (0.7 g),
Oncorhynchus clarkii

5,000

Woodward and Mauck 1980;
Mayer and Ellersieck 1986

A

Cutthroat trout (0.6 g),
Oncorhynchus clarkii

970

Woodward and Mauck 1980;
Mayer and Ellersieck 1986

A

Cutthroat trout (0.5 g),
Oncorhynchus clarkii

3,950

Woodward and Mauck 1980;
Mayer and Ellersieck 1986

A

Cutthroat trout (0.5 g),
Oncorhynchus clarkii

6,800

Mayer and Ellersieck 1986

A

Cutthroat trout (0.9 g),
Oncorhynchus clarkii

6,700

Mayer and Ellersieck 1986

A

Cutthroat trout,
Oncorhynchus clarkii

3,950

Woodward and Mauck 1980

A

Greenback cutthroat trout (0.31
g), Oncorhynchus clarkii stomias

1,550

Dwyeretal. 1995

A

Lahontan cutthroat trout (0.34-
0.57 g),

Oncorhynchus clarkii henshawi

2,250

Dwyeretal. 1995

A

Rainbow trout (3.2 g),
Oncorhynchus mykiss

1,350

1,476

Katz 1961

A

Rainbow trout,
Oncorhynchus mykiss

4,340

Macek and McAllister 1970

A

Rainbow trout (1.24 g),
Oncorhynchus mykiss

1,470

Post and Schroeder 1971

A

Rainbow trout (1.5 g),
Oncorhynchus mykiss

1,950

Johnson and Finley 1980;
Mayer and Ellersieck 1986;

A

Rainbow trout,
Oncorhynchus mykiss

2,200

Sanders et al. 1983

A

Rainbow trout,
Oncorhynchus mykiss

2,800

Sanders et al. 1983

A

Rainbow trout,
Oncorhynchus mykiss

1,100

Sanders et al. 1983

A

Rainbow trout,
Oncorhynchus mykiss

800

Sanders et al. 1983

A

Rainbow trout,
Oncorhynchus mykiss

1,500

Sanders et al. 1983

4


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()\\
MIJR

(iroup11

Species

l.( 50/l.( 50
(Jlg/I.)

SMAY

(fm/i.)

c;may

Reference

A

Rainbow trout,

900





Sanders et al. 1983



Oncorhynchus mykiss





A

Rainbow trout,

800





Sanders et al. 1983



Oncorhynchus mykiss





A

Rainbow trout (1.0 g),
Oncorhynchus mykiss

935





Marking et al. 1984

A

Rainbow trout (1.0 g),
Oncorhynchus mykiss

1,000





Marking et al. 1984

A

Rainbow trout (1.0 g),
Oncorhynchus mykiss

1,400





Marking et al. 1984

A

Rainbow trout (1.0 g),
Oncorhynchus mykiss

1,000





Marking et al. 1984

A

Rainbow trout (1.0 g),
Oncorhynchus mykiss

1,740





Marking et al. 1984

A

Rainbow trout (juvenile),
Oncorhynchus mykiss

4,835





Douglas et al. 1986

A

Rainbow trout (1.5 g),
Oncorhynchus mykiss

1,200





Mayer and Ellersieck 1986

A

Rainbow trout (0.8 g),
Oncorhynchus mykiss

1,360





Mayer and Ellersieck 1986

A

Rainbow trout (0.8 g),
Oncorhynchus mykiss

2,080





Mayer and Ellersieck 1986

A

Rainbow trout (1.1 g),
Oncorhynchus mykiss

1,900





Mayer and Ellersieck 1986

A

Rainbow trout (1.1 g),
Oncorhynchus mykiss

2,300





Mayer and Ellersieck 1986

A

Rainbow trout (0.5 g),
Oncorhynchus mykiss

1,330





Mayer and Ellersieck 1986

A

Rainbow trout (0.8 g),
Oncorhynchus mykiss

<750





Mayer and Ellersieck 1986

A

Rainbow trout (1.1 g),
Oncorhynchus mykiss

<320





Mayer and Ellersieck 1986

A

Rainbow trout (1.2 g),
Oncorhynchus mykiss

1,090





Mayer and Ellersieck 1986

A

Rainbow trout (1.1 g),
Oncorhynchus mykiss

1,460





Mayer and Ellersieck 1986

A

Rainbow trout (1.2 g),
Oncorhynchus mykiss

3,500





Mayer and Ellersieck 1986

A

Rainbow trout (1.2 g),
Oncorhynchus mykiss

3,000





Mayer and Ellersieck 1986

A

Rainbow trout (1.0 g),
Oncorhynchus mykiss

1,600





Mayer and Ellersieck 1986

A

Rainbow trout (1.0 g),
Oncorhynchus mykiss

1,100





Mayer and Ellersieck 1986

A

Rainbow trout (1.0 g),
Oncorhynchus mykiss

1,200





Mayer and Ellersieck 1986

A

Rainbow trout (1.0 g),
Oncorhynchus mykiss

780





Mayer and Ellersieck 1986

A

Rainbow trout (1.0 g),
Oncorhynchus mykiss

1,450





Mayer and Ellersieck 1986

5


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()\\
MIJR

(iroup11

Species

l.( 50/l.( 50
(Jlg/I.)

SMAY

(fm/i.)

(;\1AY

(flli/l.)

Reference

A

Rainbow trout (0.48-1.25 g),
Oncorhynchus mykiss

1,880





Dwyeretal. 1995

A

Rainbow trout (juvenile; 2.7 g),
Oncorhynchus mykiss

5,400





Ferrari et al. 2004

A

Rainbow trout (19.7 g),
Oncorhynchus mykiss

860





Phipps and Holcombe 1985

A

Atlantic salmon (0.4 g),
Salmo salar

4,500





Mayer and Ellersieck 1986

A

Atlantic salmon (0.8 g),
Salmo salar

2,070





Mayer and Ellersieck 1986

A

Atlantic salmon (0.8 g),
Salmo salar

1,180





Mayer and Ellersieck 1986

A

Atlantic salmon (0.4 g),
Salmo salar

905





Mayer and Ellersieck 1986

A

Atlantic salmon (0.8 g),
Salmo salar

2,010





Mayer and Ellersieck 1986

A

Atlantic salmon (0.8 g),
Salmo salar

1,430





Mayer and Ellersieck 1986

A

Atlantic salmon (0.2 g),
Salmo salar

500

1,119



Mayer and Ellersieck 1986

A

Atlantic salmon (0.2 g),
Salmo salar

1,000



Mayer and Ellersieck 1986

A

Atlantic salmon (0.2 g),
Salmo salar

1,150



1,510

Mayer and Ellersieck 1986

A

Atlantic salmon (0.2 g),
Salmo salar

1,100



Mayer and Ellersieck 1986

A

Atlantic salmon (0.2 g),
Salmo salar

1,350





Mayer and Ellersieck 1986

A

Atlantic salmon (0.2 g),
Salmo salar

220





Mayer and Ellersieck 1986

A

Atlantic salmon (0.2 g),
Salmo salar

900





Mayer and Ellersieck 1986

A

Atlantic salmon (0.2 g),
Salmo salar

1,000





Mayer and Ellersieck 1986

A

Brown trout,
Salmo trutta

1,950





Macek and McAllister 1970

A

Brown trout (0.6 g),
Salmo trutta

6,300

2,036



Johnson and Finley 1980;
Mayer and Ellersieck 1986

A

Brown trout (fingerling),
Salmo trutta

2,000



Mayer and Ellersieck 1986

A

Brown trout (fry),
Salmo trutta

700





Lakotaetal. 1981

A

Brook trout (1.15 g),
Salvelinus fontinalis

1,070





Post and Schroeder 1971

A

Brook trout (2.04 g),
Salvelinus fontinalis

1,450

1,629

1,269

Post and Schroeder 1971

A

Brook trout (1.0 g),
Salvelinus fontinalis

680

Mayer and Ellersieck 1986

A

Brook trout (0.7 g),
Salvelinus fontinalis

4,560





Mayer and Ellersieck 1986

6


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()\\
MIJR

(iroup11

Species

l.( 50/l.( 50
(Jlg/I.)

SMAY

(fm/i.)

(;\1AY

(flli/l.)

Reference

A

Brook trout (0.7 g),
Salvelinus fontinalis

2,130





Mayer and Ellersieck 1986

A

Brook trout (0.7 g),
Salvelinus fontinalis

1,130

Mayer and Ellersieck 1986

A

Brook trout (0.8 g),
Salvelinus fontinalis

1,200

Mayer and Ellersieck 1986

A

Brook trout (0.8 g),
Salvelinus fontinalis

1,290

Mayer and Ellersieck 1986

A

Brook trout (1.3 g),
Salvelinus fontinalis

4,500

Mayer and Ellersieck 1986

A

Lake trout (1.7 g),
Salvelinus namaycush

690

988.1

Johnson and Finley 1980;
Mayer and Ellersieck 1986

A

Lake trout (1.7 g),
Salvelinus namaycush

740

Mayer and Ellersieck 1986

A

Lake trout (1.7 g),
Salvelinus namaycush

920

Mayer and Ellersieck 1986

A

Lake trout (0.5 g),
Salvelinus namaycush

872

Mayer and Ellersieck 1986

A

Lake trout (2.6 g),
Salvelinus namaycush

2,300

Mayer and Ellersieck 1986

B

Goldfish (0.9 g),
Carassius auratus

13,200

14,907

14,907

Macek and McAllister 1970

B

Goldfish (0.9 g),
Carassius auratus

12,800

Mayer and Ellersieck 1986

B

Goldfish (juvenile; 1.3-3.3 g),
Carassius auratus

17,500

Pfeiffer et al. 1997

B

Goldfish (14.2 g),
Carassius auratus

16,700

Phipps and Holcombe 1985

B

Common carp (0.6 g),
Cyprinus carpio

5,280

4,153

4,153

Macek and McAllister 1970

B

Common carp (0.38 g),
Cyprinus carpio

1,700

Chin and Sudderuddin 1979

B

Common carp (fry),
Cyprinus carpio

4,220

Lakotaetal. 1981

B

Common carp (20-34 mm),
Cyprinus carpio

7,850

de Mel and Pathiratne 2005

B

European chub (12.43 cm; 18.14
g)>

Leuciscus cephalus

8,656

8,656

8,656

Verep 2006

B

Fathead minnow (0.5 g),
Pimephales promelas

14,000

7,367

7,367

Mayer and Ellersieck 1986

B

Fathead minnow (0.8 g),
Pimephales promelas

14,600

Macek and McAllister 1970;
Sanders et al. 1983

B

Fathead minnow (0.8 g),
Pimephales promelas

7,700

Mayer and Ellersieck 1986

B

Fathead minnow (larvae),
Pimephales promelas

>1,600

Norberg-King 1989

B

Fathead minnow (0.32-0.56 g),
Pimephales promelas

5,210

Dwyeretal. 1995

B

Fathead minnow (2 mo),
Pimephales promelas

9,000

Carlson 1971

7


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()\\
MIJR

(iroup11

Species

l.( 50/l.( 50
(Jlg/I.)

SMAY

(fm/i.)

(;\1AY

(flli/l.)

Reference

B

Fathead minnow (0.3 g),
Pimephales promelas

5,010





Phipps and Holcombe 1985

B

Fathead minnow (28 d),
Pimephales promelas

8,930

Geigeretal. 1985; 1988

B

Fathead minnow (28 d),
Pimephales promelas

10,400

Geigeretal. 1985; 1988

B

Fathead minnow (29 d),
Pimephales promelas

6,670

Geigeretal. 1985; 1988

B

Fathead minnow (31 d),
Pimephales promelas

9,470

Geigeretal. 1985; 1988

B

Bonytail chub (0.29-0.52 g),
Gila elegans

3,490

2,655

2,655

Dwyeretal. 1995

B

Bonytail chub (6 d),
Gila elegans

2,020

Beyers etal. 1994

B

Colorado pikeminnow (0.32-
0.34 g),

Ptychochelius lucius

3,070

2,005

2,005

Dwyeretal. 1995

B

Colorado pikeminnow (26 d),
Ptychochelius lucius

1,310

Beyers etal. 1994

B

Razorback sucker (0.31-0.32 g),
Xyrauchen texanus

4,350

4,350

4,350

Dwyeretal. 1995

B

Black bullhead (1.2 g),
Ameiurus melas

20,000

20,000

20,000

Macek and McAllister 1970

B

Channel catfish (1.5 g),
Ictalurus punctatus

15,800

8,075

8,075

Macek and McAllister 1970

B

Channel catfish (0.3 g),
Ictalurus punctatus

1,300

Brown etal. 1979

B

Channel catfish (1.5 g),
Ictalurus punctatus

7,790

Mayer and Ellersieck 1986

B

Channel catfish (fingerling),
Ictalurus punctatus

17,300

Mayer and Ellersieck 1986

B

Channel catfish (27.6 g),
Ictalurus punctatus

12,400

Phipps and Holcombe 1985

B

Walking catfish (17-18 cm; 60-
70 g),

Clarias batrachus

46,850

27,609

27,609

Tripathi and Shukla 1988

B

Walking catfish (14 cm; 25 g),
Clarias batrachus

16,270

Lata et al. 2001

B

Guppy (2.0 cm),
Poecilia reticulata

2,515

2,515

2,515

Gallo et al. 1995

B

Gila topminnow (219 mg),
Poeciliopsis occidentalis

>3,000

>3,000

>3,000

Dwyeretal. 1999b

B

Striped bass (56 d),
Morone saxatilis

760

1,322

1,322

Palawski et al. 1985

B

Striped bass,
Morone saxatilis

2,300

Palawski et al. 1985

B

Green sunfish (1.1 g),
Lepomis cyanellus

9,460

9,460

9,460

Mayer and Ellersieck 1986

B

Redear sunfish (1.1 g),
Lepomis microlophus

11,200

11,200

7,920

Macek and McAllister 1970

8


-------
()\\
MIJR

(iroup11

Species

l.( 50/l.( 50
(Jlg/I.)

SMAY

(fm/i.)

(;\1AY

(flli/l.)

Reference

B

Bluegill,

Lepomis macrochirus

14,000





McCann and Young 1969

B

Bluegill (1.2 g),
Lepomis macrochirus

6,760





Macek and McAllister 1970

B

Bluegill,

Lepomis macrochirus

16,000





Sanders et al. 1983

B

Bluegill,

Lepomis macrochirus

8,200





Sanders et al. 1983

B

Bluegill,

Lepomis macrochirus

5,400





Sanders et al. 1983

B

Bluegill,

Lepomis macrochirus

5,200





Sanders et al. 1983

B

Bluegill,

Lepomis macrochirus

1,800





Sanders et al. 1983

B

Bluegill,

Lepomis macrochirus

2,200





Sanders et al. 1983

B

Bluegill,

Lepomis macrochirus

1,000





Sanders et al. 1983

B

Bluegill (1.2 g),
Lepomis macrochirus

5,230





Mayer and Ellersieck 1986

B

Bluegill (0.6 g),
Lepomis macrochirus

5,047

5,261



Mayer and Ellersieck 1986

B

Bluegill (0.4 g),
Lepomis macrochirus

7,400



Mayer and Ellersieck 1986

B

Bluegill (0.4 g),
Lepomis macrochirus

5,200





Mayer and Ellersieck 1986

B

Bluegill (0.8 g),
Lepomis macrochirus

16,000





Mayer and Ellersieck 1986

B

Bluegill (0.8 g),
Lepomis macrochirus

7,000





Sanders et al. 1983; Mayer
and Ellersieck 1986

B

Bluegill (0.8 g),
Lepomis macrochirus

8,200





Mayer and Ellersieck 1986

B

Bluegill (0.4 g),
Lepomis macrochirus

6,200





Mayer and Ellersieck 1986

B

Bluegill (0.7 g),
Lepomis macrochirus

5,400





Mayer and Ellersieck 1986

B

Bluegill (0.7 g),
Lepomis macrochirus

5,200





Mayer and Ellersieck 1986

B

Bluegill (0.7 g),
Lepomis macrochirus

1,800





Mayer and Ellersieck 1986

B

Bluegill (0.7 g),
Lepomis macrochirus

2,600





Mayer and Ellersieck 1986

B

Bluegill (0.5 g),
Lepomis macrochirus

6,970





Phipps and Holcombe 1985

B

Largemouth bass (0.9 g),
Micropterus salmoides

6,400

6,400

6,400

Macek and McAllister 1970

B

Black crappie (1.0 g),
Pomoxis nigromaculatus

2,600

2,600

2,600

Johnson and Finley 1980;
Mayer and Ellersieck 1986;

B

Greenthroat darter (133 mg),
Etheostoma lepidum

2,140

2,140

2,079

Dwyeretal. 1999b

9


-------
()\\
MIJR

(iroup11

Species

l.( 50/l.( 50
(Jlg/I.)

SMAY

(fm/i.)

(;\1AY

(flli/l.)

Reference

B

Fountain darter (62 mg),
Etheostoma fonticola

2,020

2,020



Dwyer et al. 2005

B

Yellow perch (1.4 g),
Perca flavescens

745

2,480

2,480

Macek and McAllister 1970

B

Yellow perch (0.6 g),
Perca flavescens

5,100

Johnson and Finley 1980;
Mayer and Ellersieck 1986

B

Yellow perch (1.0 g),
Perca flavescens

13,900

Mayer and Ellersieck 1986

B

Yellow perch (1.0 g),
Perca flavescens

5,400

Mayer and Ellersieck 1986

B

Yellow perch (1.0 g),
Perca flavescens

3,400

Mayer and Ellersieck 1986

B

Yellow perch (1.0 g),
Perca flavescens

1,200

Mayer and Ellersieck 1986

B

Yellow perch (0.9 g),
Perca flavescens

4,000

Mayer and Ellersieck 1986

B

Yellow perch (0.9 g),
Perca flavescens

4,200

Mayer and Ellersieck 1986

B

Yellow perch (0.9 g),
Perca flavescens

480

Mayer and Ellersieck 1986

B

Yellow perch (0.9 g),
Perca flavescens

350

Mayer and Ellersieck 1986

B

Yellow perch (1.0 g),
Perca flavescens

3,800

Mayer and Ellersieck 1986

B

Yellow perch (1.0 g),
Perca flavescens

5,000

Mayer and Ellersieck 1986

B

Yellow perch (1.0 g),
Perca flavescens

3,750

Mayer and Ellersieck 1986

B

Yellow perch (fingerling),
Perca flavescens

1,420

Mayer and Ellersieck 1986

B

Shortnosed sturgeon,
Acipenser brevirostrum

1,810

1,810

1,810

Dwyer et al. 2000

B

Nile tilapia (45-55 mm; 3.17 g),
Oreochromis niloticus

2,930

2,930

2,930

dela Cruz and Cagauan 1981

C

Green frog (Gosner stage 25

tadpole),

Rana clamitans

22,020

16,296

16,296

Boone and Bridges 1999

C

Green frog (Gosner stage 25

tadpole),

Rana clamitans

17,360

Boone and Bridges 1999

C

Green frog (Gosner stage 25

tadpole),

Rana clamitans

11,320

Boone and Bridges 1999

C

Boreal toad (200 mg),
Bufo boreas

12,310

12,310

12,310

Dwyer etal. 1999b

C

Gray tree frog (tadpole),
Hyla versicolor

2,470

2,470

2,470

Zagaetal. 1998

C

African clawed frog (embryo),
Xenopus laevis

15,250

5,136

5,136

Zagaetal. 1998

C

African clawed frog (tadpole),
Xenopus laevis

1,730

Zagaetal. 1998

10


-------
a OW MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important
warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Acute Benchmark Values

The OPP invertebrate acute benchmark value for carbaryl is 0.85 |ig/L, which is V2 the LC50 of
1.7 |ig/L, the stonefly Pteronarcella badia as described above.

The OPP fish acute benchmark value is 110 |ig/L, which is V2 the LC50 of 220 |ig/L for the
Atlantic salmon (Salmo salaf).

OW Acute Criterion

The acute criterion, or CMC, for carbaryl is 2.1 |ig/L (U.S. EPA 2012).

Genus-Level Invertebrate-Only HC05

The invertebrate acute HC05 OW calculated using invertebrate genera data only is shown in
Table 2. The invertebrate-only value was calculated following the U.S. EPA (1985)
methodology, resulting in a value of 3.074 |ig/L (Table 3).

Table 2. Carbaryl invertebrate SMAVs and GMAVs (ng/L).

(iOIIIIS

Species

SMAY

CMAY

CMAY Kiink

Aplexa

hyonorum

27,000

27,000

20

Anodonta

imbecillis

24,632

24,632

19

Lumbriculus

variegatus

8,200

8,200

18

Orconectes

virilis

2,112

2,462

17

Orconectes

immunis

2,870

Procambarus

clarkii

1,000

1,378

16

Procambarus

sp.

1,900

Cambarus

bartoni

839.6

840

15

Asellus

brevicaudus

280

280

14

Pontoporeia

hoyi

250

250

13

Mysis

relicta

230

230

12

Notonecta

undulata

200

200

11

Daphnia

magna

29.66

18.80

10

Daphnia

pulex

6.4

Daphnia

carinata

35

Gammarus

pseudolimnaeus

9.654

16.76

9

Gammarus

lacustris

18.76

Gammarus

fasciatus

26.00

Hyalella

azteca

15.2

15.2

8

Pteronarcella

badia

9.163

9.163

7

Simocephalus

serrulatus

8.781

8.781

6

Ceriodaphnia

dubia

5.958

5.958

5

11


-------
Genus

Species

SMAV

GMAV

GMAV Rank

Claassenia

sabulosa

5.6

5.6

4

Pteronarcvs

californica

4.8

4.8

3

Skwala

sp.

3.6

3.6

2

Isogemis

sp.

3.175

3.175

1

Table 3. Invertebrate-Only acute HCos value calculated using the only the genus-level

N

Rank

GMAV

ln(GMAV)

ln(GMAV)2

P=R/(N+1)

sqrt(P)

20

4

5.6

1.723

2.97

0.1905

0.4364



3

4.8

1.569

2.46

0.1429

0.3780



2

3.6

1.281

1.64

0.0952

0.3086



1

3.175

1.155

1.335

0.0476

0.2182



Sum:



5.73

8.40

0.4762

1.3412







S2 =

7.654

L =

0.504

A =

1.123

hc05 =

3.074

Table 4. Summary and comparison of acute values for carbaryl.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

Pesticide

OPP Invertebrate
ALB

(lowest LCso/2)
(Year published,
species)

OW ALC (FAV/2)
(Year published,
# of genera,
magnitude relative to
ALB)

OW Genus-level
Invertebrate-only
HCos/2
(# of genera, magnitude
relative to ALB)

Notes

Carbaryl

0.85 ng/L
(2022; P. badia)

2.1 (ig/L

(2012, 47 genera,
0.40X)

1.54 (ig/L

(20 genera, 0.55X)

FIFRA ALB is based on one of
four LCso values used to
generate the P. badia SMAV of
9.163 |ig/L in the 2012 carbaryl
ALC.

Figure 1 shows a genus-level sensitivity distribution for the carbaryl dataset. Major taxonomic
groups are delineated by different symbols, and invertebrate genera are identified by name. Lines
denoting the CMC, invertebrate HCos/2, and OPP acute benchmark values are also included.

12


-------
100,000.00

10,000.00

1,000.00

bJD

u.

ro
-Q

nj
U

100.00

10.00

1.00

•

Arthropod

o

Annelid

A

Mollusk

¦

Salmonid Fish

~

Other Fish

~

Amphibian

	

CMC



Genus-level Invertebrate



OPP Invert. Benchmark

	

OPP Fish Benchmark

~ ~

~ •

Cambarus •
Pontoporeia

•Asellus

* N.





~ ~

Anodonta .

>A AD

~ ~ f

„ *	Aplexa

D ~ ~ ~ ° ~

Lumbriculus

Orconectes

Procambarus

Notonecta i

LMysis.

OPP Fish Benchmark= 110 ng/L

_ •Daphnia

Simocephalus

\ Hyalella
Claassen,a\^	'^Gammarus

• «c-	Pteronarcella

^Ceriodaphnia

	^Ptexonarcys

"Skwala

X

FAV/2 = Criterion Maximum Concentration = 2.1 |_ig/L

Isogenus

• Genus-level Invertebrate HC05/2 = 1.537 ng/L
OPP Invertebrate Benchmark = 0.85 ng/L

0.10

0.0

0.1

0.2

0.3

0.4	0.5	0.6

Sensitivity Centile

0.7

0.8

0.9

1.0

Figure 1. Carbaryl genus-level SD.

Symbols represent GMAVs calculated using all quantitative data from the aquatic life criteria document for carbaryl (U.S. EPA 2012),
and additional data from the OPP benchmark document for carbaryl (U.S. EPA 2007).

13


-------
1.1.1.2 Carbaryl Chronic Toxicity Data

For chemicals lacking sufficient chronic data to satisfy the minimum taxonomic data
requirements, such as the pesticide carbaryl, EPA Office of Water (OW) calculates the final
chronic value (FCV) as the final acute value (FAV) divided by the final acute-to chronic ratio
(FACR). The Office of Pesticide Programs (OPP) will also apply Acute to Chronic Ratios
(ACRs) to acute data to calculate chronic benchmarks when chronic test data are not available.
Calculations of ACRs following OPP and OW methodologies were conducted, and the effects of
these ACRs on the resulting OPP and OW chronic values were compared.

Chronic Data Sources

The primary data source for this analysis was the 2012 freshwater carbaryl criteria document
(U.S. EPA 2012). The OPP-authored carbaryl problem formulation (U.S. EPA 2010) and
California red legged frog effects determination (U.S. EPA 2007) reports were also examined.
The latter reports did not include additional test data but did report test concentrations used to
calculate ACRs that were used to calculate chronic benchmarks. In addition, one chronic value
for Ceriodaphnia dubia was obtained from Oris et al. (1991) that was not included in the other
data sources.

ACR Calculations

ACR calculations following OW and OPP methodologies are described below. All available
chronic carbaryl data are shown in Table 5. All available acute data for species that also have
chronic data are shown in Table 6. Table 7 lists all ACRs by species and calculation method.

Invertebrate ACRs

Ceriodaphnia dubia

The ACR following the OW approach is 1.328, calculated as the acute value from Oris et al.
(1991) divided by the geometric mean of the MATCs from two replicate chronic tests performed
in the same laboratory.

The ACR following the OPP approach is 1.609, calculated as the acute value from Oris et al.
(1991) divided by the geometric mean of the NOECs from two replicate chronic tests performed
in the same laboratory as per the OPP ACR guidelines (U.S. EPA 2005).

Daphnia magna

The ACR described in the 2012 ALC deviated from the conventional OW approach. Brooke
(1991) conducted paired acute and chronic tests, with an EC50 of 10.1 ng/L, a NOEC of 4.04
Hg/L, and a LOEC of >4.04 ng/L. Because there was no MATC, OW noted the "theoretical
ACR" could fall anywhere between 1.0-2.5, and estimated the ACR as 1.581, calculated as the
acute value (10.1 ng/L) divided by the geometric mean of the NOEC and the acute value (6.388
Hg/L)-

The ACR following the OPP approach is 2.5, calculated as the acute value from Brooke (1991)
divided by the NOEC for the paired chronic test.

14


-------
Americamysis bahia

The ACR following the OW approach is 0.8530, calculated as the acute value of 8.46 ng/L from
Thursby and Champlin (1991) divided by the MATC of 9.918 ng/L from the paired chronic test.
The ACR following the OPP approach is 1.178, calculated as the acute value of 8.46 ng/L from
Thursby and Champlin (1991) divided by the No Observed Effect Concentration (NOEC) of 7.18
Hg/L from the paired chronic test. As described in the carbaryl ALC document, these ACRs are
treated as qualitative because control survival and number of young produced per female did not
meet American Society for Testing and Materials (ASTM) test requirements (U.S. EPA 2012).

Vertebrate (Fish) ACRs

Gila elegans

An ACR for this species could not be calculated following the OW approach. Beyers et al.
(1994) performed an early life stage (ELS) chronic test and a static renewal acute test. Although
the acute and chronic tests were performed in the same laboratory, the Guidelines (U.S. EPA
1985) specifies that acute test data should also be from a flow through study (except for
Daphnids, where static acute tests are acceptable). The ACR following the more flexible OPP
approach is 3.108, calculated as the acute value of 2,020 ng/L from Beyers et al. (1994) divided
by the NOEC of 650 ng/L from ELS test performed in the same laboratory.

Pimephales promelas

Two ACRs fori5, promelas could be calculated following the OW approach. An ACR of 23.82
was calculated as the acute value of 9,000 ng/L reported in Carlson (1971) divided by the MATC
of 377.9 ng/L from a paired life cycle test. An ACR of 6.256 was calculated using test data from
three studies performed at the same laboratory. The geometric mean of two acute LC50s from
tests performed at the same laboratory, 9,000 |ag/L as reported in Carlson (1971) and 5,100 |ag/L
as reported in Phipps and Holcombe (1985) was divided by the MATC of 1,073 |ag/L from an
ELS test performed in the same laboratory (Norberg-King 1989). Because ACRs calculated from
life cycle tests are preferable to those calculated from ELS test, the ACR of 23.82 is used for this
species.

The corresponding P. promelas ACRs calculated following the OPP approach are 42.86 for the
life cycle ACR and 9.326 for the ELS ACR, using the acute data described above divided by a
NOEC of 210 |ag/L from the life cycle test (Carlson 1971), and a NOEC of 720 ng/L from the
ELS test (Norberg-King 1989). As described above, the life cycle ACR of 42.86 is used by OPP
for this species.

Ptychocheilus lucius

An ACR for this species could not be calculated following the OW approach. Beyers et al.
(1994) performed an early life stage (ELS) chronic test and a static renewal acute test. Although
the acute and chronic tests were performed in the same laboratory, the Guidelines (U.S. EPA
1985) specifies that acute test data should also be from a flow through study (except for
Daphnids, where static acute tests are acceptable). Also worth noting is the study authors
reported that the water for the acute and chronic tests was inadvertently aged differently, with the
acute tests having higher dissolved oxygen and pH, and lower hardness and alkalinity, than the
chronic tests.

15


-------
The ACR following the more flexible OPP approach is 2.944, calculated as the acute value of
1,310 |ag/L from Beyers et al. (1994) divided by the NOEC of 445 ng/L from ELS test
performed in the same laboratory. Despite the differences in water quality from the acute and
chronic Beyers et al. (1994) tests, they were still treated as being more similar to one another
than the other acute test for this species, which was an unmeasured static test (Dwyer et al.

1995).

Final ACRs

The final ACRs (FACRs) for the two approaches, expressed as the geometric mean of all
available ACRs, is 3.684 following the OW approach, and 4.361 following the OPP approach.
The OW FACR consists of ACRs for C. dubia, I), magna (using the estimated Maximum
Acceptable Toxicant Concentration (MATC) following the 2012 ALC methodology), and the life
cycle ACR for P. promelas.

The Guidelines (U.S. EPA 1985) specify that if the ACRs appear to increase or decrease as the
species mean acute values (SMAVs) increase, the FACR should be calculated as the geometric
mean for those species whose SMAVs are close to the final acute value (FAV).This is the case
for carbaryl, and following the approach used in the 2005 ALC, the FACR is calculated as the
geometric mean of the acutely sensitive invertebrate species. When limited to invertebrate
species, the FACR following the OW approach is calculated as the geometric mean of the ACRs
for C. dubia (1.328) and D. magna (1.581). Because the final chronic value cannot be larger than
the final acute value, the calculated ACR of 1.449 is rounded up to 2. The invertebrate-only
FACR following the OPP approach, but applying the Guidelines stipulation that the FACR
should be calculated using species with SMAVs close to the FAV if ACRs are proportional to
acute sensitivity, is the geometric mean of the ACRs for C. dubia (1.609) and D. magna (2.5), or
2.006.

The OPP FACR consists of ACRs for C. dubia, D. magna, and P. promelas, as well as G.
elegans, and P. lucius. The A. bahia qualitative ACR was not included here because the chronic
test did not meet ASTM test acceptability guidelines.

Comparison of Freshwater Chronic Values for Carbaryl

OPP Chronic Benchmarks

For carbaryl, the freshwater invertebrate chronic benchmark is 0.5 |ig/L, calculated as an LC50
of 1.7 |ig/L for Pteronarcella badia (Mayer and Ellersieck 1986) divided by the OPP-calculated
ACR of 3.73 for D. magna.

The freshwater fish chronic benchmark is 6.8 |ig/L, calculated as the LC50 of 250 |ig/L for
Salmo salar divided by the OPP-calculated ACR of 36.67 for P. promelas.

OW Freshwater Chronic Values - All Taxa

Final chronic concentrations following the ACR methodology are calculated by dividing the final
acute value by a final ACR (FACR). For carbaryl, the FAV calculated using data from all taxa is
4.219 |ag/L (U.S. EPA 2012). The final chronic value following the OW-ACR approach is 2.110
Hg/L (4.219 |ag/L 2), and the final chronic value following the OPP-ACR approach (with the
Guidelines stipulation described above) is 2.103 |ag/L (4.219 |ag/L ^ 2.006).

16


-------
OW Freshwater Chronic Values - Invertebrate-Only Data

Final chronic concentrations for the invertebrate-only carbaryl dataset are calculated by dividing
the final invertebrate acute value by an ACR. This dataset was comprised of acute invertebrate
test data found in the 2012 ALC and Appendix L of U.S. EPA (2007). The resulting acute HCos
calculated from the 20 invertebrate genera using the calculated following the Guidelines (U.S.
EPA 1985) methodology was 3.074 ng/L. The final invertebrate chronic value following the
OW-ACR approach is 1.537 ng/L (3.074 ng/L -h 2), and the final chronic value following the
OPP-ACR approach is 1.532 jig/L (3.074 jig/L - 2.006).

Table 8 lists all chronic values calculated following the different approaches.

17


-------
Table 5. Chronic test data for carbaryl.

All concentrations expressed as ng/L, values are grouped by genus.

Genus

Species

NOEC

LOEC

MATC

Reference

Test data reported in:

Notes

2012 ALC

2007
OPP

2010
OPP



Invertebrates

Ceriodaphnia

dubia

8

14

10.58

Oris et al. 1991

Appendix C







Ceriodaphnia

dubia

6.5

8

7.211

Oris et al. 1991

Appendix Cb



























Daphnia

magna

1.5

3.3

2.225

Surprenant 1985

Appendix C

Table 21





Daphnia

magna

4.04

>4.04

6.388°

Brooke 1991

Appendix C



























Americamysis

bahia

7.18

13.7

9.918

Thursby and
Champlin 1991

Appendix D





Low control survival
and young per female

Vertebrates

Gila

elegans

650

1,240

897.8

Beyers et al.
1994

Appendix C





ELS test





















Pimephales

promelas

210

680

377.9

Carlson 1971

Appendix C





Life cycle test

Pimephales

promelas

720

1,600

1,073

Norberg-King
1989

Appendix C





ELS test





















Ptychocheilus

lucius

445

866

620.8

Beyers et al.
1994

Appendix C





ELS test

a- Estimated from Figure 1 of Oris et al. (1991) using WebPlotDigitizer (https://automeris.io/WebPlotDigitizer/)
b- Reported in Table 2 of Oris et al. (1991)

Calculated in 2012 ALC as geometric mean of NOEC and acute value

18


-------
Table 6. Acute Carbaryl Test Data for Species with Chronic Data.

All concentrations expressed as ng/L.	

Genus

Species

EC50 or
LC50

Reference

Test data reported in:

2012 ALC

2007 OPP

2010
OPP

Notes

Invertebrates

Ceriodaphnia

dubia

11.6

Oris et al. 1991

Appendix A

Paired with Oris et al. 1991 chronic values

Ceriodaphnia

dubia

3.6

Brooke 1990, 1991

Appendix A

Not used

Daphnia

magna

12

Lakotaetal. 1981

Appendix A

Not used

Daphnia

magna

5.6

Sanders et al. 1983

Appendix A

Table 21

Not used

Daphnia

magna

10.1

Brooke 1991

Appendix A

Paired with Brooke 1991 chronic values

Americamysis

bahia

IA6

Thursby and Champlin
1991

Appendix B

Paired with Thursby and Champlin 1991
chronic values

Americamysis

bahia

5.7

Lintott 1992a

Appendix B

Table 4

Not used

Vertebrates

Gila

elegans

2,020

Beyers etal. 1994

Appendix A

Paired with Beyers et al. 1994 chronic
value (OPP-ACR only)	

Gila

elegans

3,490

Dwyeretal. 1995

Appendix A

Not used

Pimephales

promelas

14,000

Mayer and Ellersieck 1986

Appendix A





Not used

Pimephales

promelas

14,600

Macek and McAllister
1970; Sanders etal. 1983

Appendix A





Not used

Pimephales

promelas

7,700

Mayer and Ellersieck 1986

Appendix A





Not used

Pimephales

promelas

>1,600

Norberg-King 1989

Appendix A





Not used

Pimephales

promelas

5,210

Dwyeretal. 1995

Appendix A





Not used

Pimephales

promelas

9,000

Carlson 1971

Appendix A





Paired with Carlson 1971 (LC-ACR) and
Norberg-King 1989 (ELS ACR) chronic
value

Pimephales

promelas

5,010

Phipps and Holcombe
1985

Appendix A





Paired with Norberg-King 1989 (ELS
ACR) chronic value

Pimephales

promelas

9,470

Geigeretal. 1985; 1988

Appendix A





Not used

Pimephales

promelas

8,930

Geigeretal. 1985; 1988

Appendix A





Not used

Pimephales

promelas

10,400

Geigeretal. 1985; 1988

Appendix A





Not used

Pimephales

promelas

6,670

Geigeretal. 1985; 1988

Appendix A





Not used



Ptychocheilus

lucius

1,310

Beyers etal. 1994

Appendix A





Paired with Beyers et al. 1994 chronic
value (OPP-ACR only)

Ptychocheilus

lucius

3,070

Dwyeretal. 1995

Appendix A





Not used

19


-------
Table 7. ACRs by species and calculation method.

Genus

Species

ACR

Notes

OW-ACR

OPP-ACR

Invertebrates

Ceriodaphnia

dubia

1.328

1.609



Daphnia

magna

1.581

2.5



Americamvsis

bahia

0.8530

1.178

Qualitative ACR

Vertebrate

Gila

elegans

N/A

3.108

ELS chronic test

Pimephales

promelas

23.82

42.86

Life cycle chronic test

Pimephales

promelas

6.256

9.326

ELS chronic test

Ptvchocheilus

lucius

N/A

2.944

ELS chronic test



All Taxa"

3.684

4.361



All Invertebrates (FACR)

2

2.006

OW-FACR rounded up to 2

1 Of the two ACRs for P. promelas, only the life cycle test was included in this calculation.

Table 8. Summary and comparison of freshwater chronic values for carbaryl.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

Pesticide

OPP Most Sensitive ALB
(Year published, species)

OW ALC (# of ACRs filled,
magnitude relative to ALB)

OW Invertebrate-only
HCos
(# of ACRs filled,
magnitude relative to ALB)

Carbaryl

0.5 ng/L

(2022; estimated NOAEC value for

Pteronarcella badia calculated using
the ACR for Daphnia magna)

2.1 (ig/L
(ALC, 0.24X)

1.54 (ig/L
(0.32X)

1.1.1.3 Carbaryl References

MRID 40098001: Mayer, F.L. and M.R. Ellersieck. 1986. Manual of acute toxicity:
Interpretation and data base for 410 chemicals and 66 species of freshwater animals. Resour.
Publ. No. 160, U.S. Dep. Interior, Fish Wildl. Serv., Washington, DC. 505 p.

Andreu-Moliner, E.S., M.M. Almar, I. Legarra and A. Nunez. 1986. Toxicity of some ricefteld
pesticides to the crayfish P. clarkii, under laboratory and field conditions in Lake Albufera
(Spain). J. Environ. Sci. Health Part B. 21(6): 529-537.

Bailey, H.C., and D.H.W. Liu. 1980. Lumbriculus variegatus, a Benthic Oligochaete, as a
Bioassay Organism. ASTM Spec. Tech. Publ., 205-215.

Beyers, D.W., T.J. Keefe and C.A. Carlson. 1994. Toxicity of carbaryl and malathion to two
federally endangered fishes, as estimated by regression and ANOVA. Environ. Toxicol. Chem.
13(1): 101-107.

Boone, M.D. and C.M. Bridges. 1999. The effect of temperature on the potency of carbaryl for
survival of tadpoles of the green frog (Rana clamitans). Environ. Toxicol. Chem. 18(7): 1482
1484.

20


-------
Brooke, L.T. 1990. Center for Lake Superior Environmental Studies, University of Wisconsin
Superior, Superior, WI. (Memorandum to R.L. Spehar, U.S. EPA, Duluth, MN. January 30).

Brooke, L.T. 1991. Results of freshwater exposures with the chemicals atrazine, biphenyl,
butachlor, carbaryl, carbazole, dibenzofuran, 3,3'-dichlorobenzidine, dichlorvos, 1,2-
epoxyethylbenzene (styrene oxide), isophorone, isopropalin, oxychlordane, pentachloroanisole,
propoxur (baygon), tetrabromobisphenol a, 1,2,4,5-tetrachlorobenzene, and 1,2,3-
trichloropropane to selected freshwater organisms. Center for Lake Superior Environmental
Studies, University of Wisconsin-Superior, Superior, WI. 110 p.

Brown, K.W., D.C. Anderson, S.G. Jones, L.E. Deuel and J.D. Price. 1979. The relative toxicity
of four pesticides in tap water and water from flooded rice paddies. Int. J. Environ. Stud. 14(1):
49-53.

Carlson, A.R. 1971. Effects of long-term exposure to carbaryl (sevin) on survival, growth, and
reproduction of the fathead minnow (Pimephales promelas). J. Fish. Res. Board Canada. 29: 583-
587.

Chin, Y.N. and K.I. Sudderuddin. 1979. Effect of methamidophos on the growth rate and
esterase activity of the common carp Cyprinus carpio L. Environ. Pollut. 18(3): 213-220.

de Mel, G.W.J.L.M.V.T.M. and A. Pathiratne. 2005. Toxicity assessment of insecticides
commonly used in rice pest management to the fry of common carp, Cyprinus carpio, a food fish
culturable in rice fields. J. Appl. Ichthyol. 21(2): 146-150.

dela Cruz, C.R. and A.G. Cagauan. 1981. Preliminary study on the bioassay of seven pesticides
and five weedicides with tilapia, carps, clam and shrimp as test species. Fish. Res. J. Philipp.
6(1): 11-18.

Douglas, M.T., D.O. Chanter, I.B. Pell and G.M. Burney. 1986. A proposal for the reduction of
animal numbers required for the acute toxicity to fish test (LC50 determination). Aquat. Toxicol.
8(4): 243-249.

Dwyer, F.J., L.C. Sappington, D.R. Buckler and S.B. Jones. 1995. Use of surrogate species in
assessing contaminant risk to endangered and threatened fishes. EPA/600/R-96/029, U.S. EPA,
Washington, D.C.

Dwyer, F.J., D.K. Hardesty, C.E. Henke, C.G. Ingersoll, D.W. Whites, D.R. Mount and C.M.
Bridges. 1999b. Assessing contaminant sensitivity of endangered and threatened species:

Effluent toxicity tests. EPA 600/R-99/099, U.S. EPA, Washington, D.C.

Dwyer, F.J., D.K. Hardesty, C.G. Ingersoll, J.L. Kunz and D.W. Whites. 2000. Assessing
contaminant sensitivity of American shad, Atlantic sturgeon and shortnose sturgeon, Final
Report - February 2000. Final Rep., U.S. Geol. Surv., Columbia Environ. Res. Ctr., Columbia,
MO.

Dwyer, F.J., F.L. Mayer, L.C. Sappington, D.R. Buckler, C.M. Bridges, I.E. Greer, D.K.
Hardesty, C.E. Henke, C.G. Ingersoll, J.L. Kunz, D.W. Whites, T. Augspurger, D.R. Mount, K.
Hattala, and G.N. Neuderfer. 2005. Assessing contaminant sensitivity of endangered and
threatened aquatic species: Part I. Acute toxicity of five chemicals. Arch. Environ. Contam.
Toxicol. 48: 143-154.

21


-------
Federle, P.F. and W.J. Collins. 1976. Insecticide toxicity to three insects from Ohio ponds. Ohio
J. Sci. 76(1): 19-24.

Ferrari, A., O.L. Anguiano, J. Soleno, A. Venturino and A.M. Pechen de D' Angelo. 2004.
Different susceptibility of two aquatic vertebrates (Oncorhynchus mykiss and Bufo arenarum) to
azinphos methyl and carbaryl. Compar. Biochem. Physiol. Part C. 139: 239-243.

Gallo, D., A. Merendino, J. Keizer, and L.Vittozzi. 1995. Acute toxicity of two carbamates to the
guppy (Poecilia reticulata) and the zebrafish (Brachydanio rerio). Sci. Total Environ. 171: 131
136.

Geiger, D. L., C.E. Northcott, D.J. Call and L.T. Brooke. 1985. Acute toxicities of organic
chemicals to fathead minnows (Pimephales promelas). Vol. 2. Center for Lake Superior
Environmental Studies, Univ. of Wisconsin-Superior, Superior, WI.

Geiger, D.L., D.J. Call and L.T. Brooke. 1988. Acute toxicities of organic chemicals to fathead
minnows (Pimephales promelas) Volume IV. Center for Lake Superior Environmental Studies,
University of Wisconsin-Superior, WI.

Johnson, I C., A.E. Keller and S.G. Zam. 1993. A method for conducting acute toxicity tests with
the early life stages of freshwater mussels. In: Environmental toxicology and risk assessment.
Landis, W.G., J.S. Hughes and M.A. Lewis (Eds.), ASTM STP 1179. American Society for
Testing and Materials, Philadelphia, PA. pp. 381-396.

Johnson, W.W. and M.T. Finley. 1980. Handbook of acute toxicity of chemicals to fish and
aquatic invertebrates. Resour. Publ. 137, Fish Wildl. Serv., U.S. D.I., Washington, D.C. 98 p.

Katz, M. 1961. Acute toxicity of some organic insecticides to three species of salmonids and to
the threespine stickleback. Trans. Am. Fish. Soc. 90: 264-268.

Lakota, S., A. Raszka and I. Kupczak. 1981. Toxic effect of cartap, carbaryl, and propoxur on
some aquatic organisms. Acta Hydrobiol. 23(2): 183-190.

Landrum, P.F. and W.S. Dupuis. 1990. Toxicity and toxicokinetics of pentachlorophenol and
carbaryl to Pontoporeia hoyi and Mysis relicta. In: Aquatic toxicology and risk assessment, 13th
Volume. Landis, W.G. and W.H. Van der Schalie (Eds.). ASTM STP 1096. American Society
for Testing and Materials, Philadelphia, PA. pp. 278-289.

Lata, S., K. Gopal, and N.N. Singh. 2001. Toxicological Evaluations and Morphological Studies
in a Catfish Clarias batrachus Exposed to Carbaryl and Carbofuran. J. Ecophysiol. Occup. Health
1(1-2): 121-130.

Lintott, D.R. 1992. Carbaryl technical: acute toxicity to the mysid, Mysidopsis bahia, under
flow-through test conditions. Laboratory Project ID: J9112004a. Study performed by Toxikon
Environmental Sciences for Rhone-Poulenc Ag Company.

Macek, K.J. and W.A. McAllister. 1970. Insecticide susceptibility of some common fish family
representatives. Trans. Am. Fish. Soc. 99(1): 20-27.

Marking, L.L., T.D. Bills and J.R. Crowther. 1984. Effects of five diets on sensitivity of rainbow
trout to eleven chemicals. Prog. Fish-Cult. 46: 1-5.

22


-------
Mayer, F.L. and M.R. Ellersieck. 1986. Manual of acute toxicity: Interpretation and database for
410 chemicals and 66 species of freshwater animals. Resour. Publ. No. 160, U.S. Dep. Interior,
Fish Wildl. Serv., Washington, DC. 505 p.

McCann, J.A. and R. Young. 1969. Sevin: toxicity to bluegill: test no. 142. U.S. Agricultural
Research Service, Pesticides Regulation Div., Animal Biology Laboratory. Unpublished study;
CDL: 104387-A.

McNulty, E.W., F.J. Dwyer, M.R. Ellersieck, E.I. Greer, C.G. Ingersoll and C.F. Rabeni. 1999.
Evaluation of ability of reference toxicity tests to identify stress in laboratory populations of the
amphipod Hyalella azteca. Environ. Toxicol. Chem. 18(3): 544-548.

Norberg-King, T.J. 1989. An evaluation of the fathead minnow seven-day subchronic test for
estimating chronic toxicity. Environ. Toxicol. Chem. 8(11): 1075-1089.

Oris, J.T., R.W. Winner and M.V. Moore. 1991. A four-day survival and reproduction toxicity
test for Ceriodaphnia dubia. Environ. Toxicol. Chem. 10(2): 217-224.

Palawski, D., J.B. Hunn and F.J. Dwyer. 1985. Sensitivity of young striped bass to organic and
inorganic contaminants in fresh and saline waters. Trans. Am. Fish. Soc. 114(5): 748-753.

Pfeiffer, C.J., B. Qiu and C.H. Cho. 1997. Electron microscopic perspectives of gill pathology
induced by 1-naphthyl-N-methylcarbamate in the goldfish (Carassius auratus Linnaeus). Histol.
Histopathol. 12(3): 645-653.

Phipps, G.L. and G.W. Holcombe. 1985. A method for aquatic multiple species toxicant testing:
Acute toxicity of 10 chemicals to 5 vertebrates and 2 invertebrates. Environ. Pollut. Ser. A 38(2):
141-157.

Phipps, G.L. and G.W. Holcombe. 1990. Toxicity of sevin (carbaryl) to Chinook salmon. U.S.
EPA, Duluth, MN. (Memorandum to L. Brooke, Center of Lake Superior Environmental Studies,
University of Wisconsin-Superior, WI. September 11).

Post, G. and T.R. Schroeder. 1971. The toxicity of four insecticides to four salmonid species.
Bull. Environ. Contam. Toxicol. 6(2): 144-155.

Sanders, H.O. 1969. Toxicity of pesticides to the crustacean Gammarus lacustris. Tech. Pap. No.
25, U.S. D.I., Bur. Sports Fish. Wildl., Fish Wildl. Serv., Washington, D.C. 18 p.

Sanders, H.O. and O.B. Cope. 1966. Toxicities of several pesticides to two species of
cladocerans. Trans. Am. Fish. Soc. 95(2): 165-169.

Sanders, H.O., M.T. Finley and J.B. Hunn. 1983. Acute toxicity of six forest insecticides to three
aquatic invertebrates and four fishes. Tech. Pap. No. 110, U.S. Fish Wildl. Serv., Washington,
D.C. pp.1-5.

Santharam, K.R., B. Thayumanavan and S. Krishnaswamy. 1976. Toxicity of some insecticides
to Daphnia carinata King, and important link in the food chain in the freshwater ecosystems.
Indian J. Ecol. 3: 70-73.

Schafers, C. 2002. Chloroperla grammatica, Acute toxicity test, 96 h exposure: carbaryl;
substance, technical. Lab Project Number: C018556: ACS-001/4-26/N. Unpublished study

23


-------
prepared by Fraunhofer-Institute for Molecular Biology and Applied Ecology. 31 p. {OPPTS
850.1020}.

Simon, K.A. 1982. Acute toxicity of carbaryl, alpha naphthol and sevin-4-oil tank mix to
Cambarus bartoni and Orconectes virilis. In: Environmental monitoring report from the 1982
Maine cooperative spruce budworm suppression project. Maine Forest Service, Dept. of
Conservation, Augusta, ME. pp. 61-91.

Stephan, C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. 1985.
Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic
Organisms and their Uses. PB85-227049. Office of Research and Development. Duluth, MN,
Narragansett, RI, Corvallis, OR.

Surprenant, D. 1985a. Acute toxicity of sevin technical to sheepshead minnow (Cyprinodon
variegatus). Bionomics Report No. BW-85-4-1773: Bionomics Study No. 565.0185.6109.510.
Unpublished study prepared by Springborn Bionomics, Inc. 14 p.

Surprenant, D. 1985b. The chronic toxicity of carbaryl technical to Daphnia magna under flow
through conditions. Report No. BW-85-7-1813: Study No. 565.0185.6109.130. Unpublished
study prepared by Springborn Bionomics, Inc. 35 p.

Thursby, G.B. and D. Champlin. 1991. Flow-through acute and chronic toxicity of carbaryl to
Mysidopsis bahia. (Memorandum to D.J. Hansen. U.S. EPA, Narragansett, RI. June 13).

Tripathi, G. and S.P. Shukla. 1988. Toxicity bioassay of technical and commercial formulations
of carbaryl to the freshwater catfish, Clarias batrachus. Ecotoxicol. Environ. Saf. 15(3): 277 281.

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA 2004. Interim reregi strati on eligibility decision document for carbaryl.
https://www3.epa.gov/pesticides/chem search/reg actions/reregistration/ired PC-056801 22-

Oct.-O4.pclf

U.S. EPA. 2007. Risks of carbaryl use to the federally-listed California red legged frog (Rana
aurora draytonii). Pesticide effects determination. Office of Pesticide Programs. Washington,
D C. 20460. October 19, 2007.

U.S. EPA. 2010. Problem formulation for the environmental fate and ecological risk, endangered
species, and drinking water assessments in support of the registration review of carbaryl. Office
of Pesticide Programs. Washington, D.C. 20460. September 3, 2010.

U.S. EPA. 2012. Aquatic life ambient water quality criteria for carbaryl. Office of Water. EPA-
820-R-12-007. April 2012.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

24


-------
Verep, B.A. 2006. A research on the sensitivity of European chub to some pesticides. Fresenius
Environ. Bull. 15(12A): 1517-1520.

Woodward, D.F., and W.L. Mauck (1980). Toxicity of Five Forest Insecticides to Cutthroat
Trout and Two Species of Aquatic Invertebrates. Bull. Environ. Contam. Toxicol., 25, (6), 846-
854.

Zaga, A., E.E. Little, C.F. Rabeni and M.R. Ellersieck. 1998. Photoenhanced toxicity of a
carbamate insecticide to early life stage anuran amphibians. Environ. Toxicol. Chem. 17(12):
2543-2553.

25


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1.1.2 Comparison of Aquatic Life Toxicity Values for Methomyl: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
('CWA) (U.S. EPA 2024) are described below. Data for methomyl were gathered by OW in 2015
and combined with data from OPP's registration review document for methomyl (U.S. EPA
2010).

1.1.2.1 Methomyl Acute Toxicity Data

Acute data for methomyl were gathered by OW in 2015 and combined with data from OPP's
registration review document for methomyl (U.S. EPA 2010). (See Table 1.) Methomyl data
include thirty-nine acute effect LCsos representing 14 species in 13 genera that were classified as
"quantitative" data; and two 96-hour LCsos for the species Daphnia magna and Ictalurus
punctatus conducted in acute toxicity tests using a 24% formulation of methomyl that served as
the basis for the invertebrate and fish freshwater acute OPP benchmarks. Additional studies
using 24% and 29% methomyl formulations were included in the OPP document; however, only
the two LCsos noted above that served as the basis of the OPP fish and invertebrate benchmarks
were added to the final dataset. The final acute methomyl dataset consisted of 41 LCsos for 14
species across 13 genera, including six invertebrate species representing six genera. Ranked
invertebrate GMAVs are listed in Table 2.

Table 1. Acute toxicity data of methomyl

to freshwater aquatic organisms.

OW
MDR
Group3

Genus

Species

LC50/
EC50
(Hg/L)

SMAV
(^g/L)

GMAV
(^g/L)

Reference

D

Daphnia

magna

5

11.17

11.17

Mayer and Ellersieck 1985

D

Daphnia

magna

8.8

Mayer and Ellersieck 1986

D

Daphnia

magna

31.7

Goodman 1978

F

Chironomus

plumosus

88

88

88

Mayer and Ellersieck 1986

F

Isogenus

sp

343

343

343

Mayer and Ellersieck 1986

F

Skwala

sp

34

34

34

Johnson and Finley 1980

F

Pteronarcella

badia

69

69

69

Mayer and Ellersieck 1986

E

Gammarus

pseudolimnaeus

920

920

920

Mayer and Ellersieck 1986

B

Pimephales

promelas

2,089

2,419

2,419

Geigeretal. 1988

B

Pimephales

promelas

2,800

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

1,200

896.4

896.4

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

840

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

480

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

600

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

620

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

1,050

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

2,000

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

1,150

Mayer and Ellersieck 1986

26


-------
()\\
MDR
(Iroup1

(ion us

Species

I X 50/
I X 50
(Mli/U

S\1 AY

(MS/'-)

(IMAY

(MB/'-)

Reference

B

Lepomis

macrochirus

860





Mayer and Ellersieck 1986

B

Micropterus

salmoides

1,250

1,250

1,250

Mayer and Ellersieck 1986

A

Oncorhynchus

clarkii

6,800

6,800



Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

1,700





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

1,400





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

2,000





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

1,050



3,015

Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

860

1,337

Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

1,500





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

1,100





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

1,200





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

1,600





Mayer and Ellersieck 1986

A

Salmo

salar

1,120





Mayer and Ellersieck 1986

A

Salmo

salar

560





Mayer and Ellersieck 1986

A

Salmo

salar

700





Mayer and Ellersieck 1986

A

Salmo

salar

1,220

939.6

939.6

Mayer and Ellersieck 1986

A

Salmo

salar

1,050





Mayer and Ellersieck 1986

A

Salmo

salar

1,000





Mayer and Ellersieck 1986

A

Salmo

salar

1,150





Mayer and Ellersieck 1986

A

Salvelinus

fontinalis

2,200

1,817

1,817

Mayer and Ellersieck 1986

A

Salvelinus

fontinalis

1,500

Mayer and Ellersieck 1986

B

Ictalurus

punctatus

320

412

412

Mayer and Ellersieck 1986

B

Ictalurus

punctatus

530

Mayer and Ellersieck 1986

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important

warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

27


-------
OPP Acute Benchmark Values

The OPP invertebrate acute benchmark is 2.5 |ig/L, which is V2 of the I), magna LC50 of 5.0 |ig/L
from a test conducted with a 24% formulation of methomyl (U.S. EPA 2010).

The OPP fish acute benchmark is 160 |ig/L, which is V2 of the I. punctatus LC50 of 320 |ig/L
from a test conducted with a 24% formulation of methomyl (U.S. EPA 2010).

OW Acute Criterion

There is no acute criterion, or criterion maximum concentration (CMC), for methomyl.

An illustrative example calculated for this analysis, using all available data (Table 2) was
developed.

The FAV calculated following the U.S. EPA (1985) methodology for the 13 genera in the
methomyl dataset was 8.652 |ig/L (Table 3).

Table 2. Methomyl SMAVs and GMAVs (ng/L).

(Ion us

Species

S\1 AY

(IMAY

CMAY kit 11k

Oncorhynchus

clarkii

6,800

3,015

13

Oncorhynchus

mykiss

1,337

Pimephales

promelas

2,419

2,419

12

Salvelinus

fontinalis

1,817

1,817

11

Micropterus

salmoides

1,250

1,250

10

Salmo

salar

939.6

939.6

9

Gammarus

pseudolimnaeus

920

920

8

Lepomis

macrochirus

896.4

896.4

7

Ictalurus

punctatus

411.8

411.8

6

Isogenus

sp

343

343

5

Chironomus

plumosus

88

88

4

Pteronarcella

badia

69

69

3

Skwala

sp

34

34

2

Daphnia

magna

11.17

11.17

1

28


-------
Table 3. Genus-level acute HCos for methomyl calculated following the U.S. EPA (1985)

N

Rank

GMAV

In(GMAV)

n(GMAV)

P=R/(N+1)

sqrt(P)

13

4

88

4.477

20.05

0.2857

0.5345



3

69

4.234

17.93

0.2143

0.4629



2

34

3.526

12.44

0.1429

0.3780



1

11.17

2.413

5.82

0.0714

0.2673



Sum:



14.65

56.2

0.714

1.643















S2 =

64.73











L =

0.359











A =

2.158











hc05 =

8.652









Genus-Level Invertebrate-only HCos

The genus-level invertebrate acute HCos calculated following the U.S. EPA (1985) methodology
for the four most sensitive invertebrate genera (Table 4) in the methomyl dataset was 5.109 |ig/L
(Table 5). If the D. magna OPP benchmark value was excluded from the dataset (i.e., the value
of 5.0 |ig/L from a test using a 24% formulation of methomyl), the GMAV for I). magna would
increase to 16.70 |ig/L, and the genus-level invertebrate acute HCos would increase to 8.310
Hg/L.

Table 4. Methomyl invertebrate SMAVs and GMAVs (jiig/L).

(Ion us

Species

SMAV

(IMAY

CMAY R;t 11k

Gammarus

pseudolimnaeus

920.0

920.0

6

Isogenus

sp.

343.0

343.0

5

Chironomus

plumosus

88.00

88.00

4

Pteronarcella

badia

69.00

69.00

3

Skwala

sp.

34.00

34.00

2

Daphnia

magna

11.17*

11.17

1

* The D. magna SMAV represents two LC50 values (31.7 and 8.8 |ig/L. respectively) classified as quantitative, and
an LC50 of 5.0 |ig/L from a test using a 24% formulation of methomyl that is the basis of the OPP acute
invertebrate benchmark.

29


-------
Table 5. Genus-level invertebrate-only acute HCos for methomyl calculated using the
Guidelines algorithm.

N

Rank

GMAV

ln(GMAV)

ln(GMAV)2

P=R/(N+1)

sqrt(P)

6

4

88

4.477

20.05

0.5714

0.7559



3

69

4.234

17.93

0.4286

0.6547



2

34

3.526

12.44

0.2857

0.5345



1

11.17

2.413

5.82

0.1429

0.3780



Sum:



14.65

56.2

1.429

2.323







S2 =

32.36

L =

0.359

A =

1.631

hc05 =

5.109

Note: The most sensitive GMAV for Daphnia includes an LC50 of 5.0 |ig/L conducted in a test
using a 24% methomyl formulation that is the basis for the OPP invertebrate acute benchmark
value.

Table 6. Summary and comparison of acute values for methomyl. Magnitude relative to ALB
is the OPP ALB/OW value, the ratio for the OPP value/OW value for each value comparison. A
ratio <1 indicates the OPP value is lower than the OW value.

Pesticide

Invertebrate

ALB
(lowest LCso/2)
(Year published,
species)

OW ALC (FAV/2)
(Year published, #

of genera,
magnitude relative
to ALB)

OW Genus-level
Invertebrate-only
H Cos/2
(# of genera, magnitude
relative to ALB)

Notes

Methomyl

2.5 ng/L
(2010; Daphnia
magna)

4.326 ng/L
(illustrative example
calculated for this
analysis, 8 genera,
0.58X)

2.55 ng/L
(6 genera, 0.98X)

The FIFRA ALB of 2.5
|ig/L was calculated as
half the LC50 from a
water flea (J), magna)
test conducted with 24%
pure methomyl (Mayer
and Ellersieck 1986).

Figure 1 shows a genus-level sensitivity distribution for the methomyl dataset. Major taxonomic
groups are delineated by different symbols, and invertebrate genera are identified by name. Lines
denoting the OPP acute benchmark values, the illustrative ALC example, and invertebrate-only
acute HC05/2 are included.

30


-------
10,000 -

1,000

M

">
E
o

•	Arthropod

¦ Salmonid Fish

~	Other Fish

	FAV/2 = "Criterion Maximum Concentration"

	Genus-level Invertebrate

	OPP Invert. Benchmark

•- OPP Fish Benchmark

Isogenus •

\

Gammarus

OPP Fish Benchmark = 160 |ig/L

100

• Chironomus
• Pteronarcella

CD

• Skwala

10

• Daphnia

FAV/2 = "Criterion Maximum Concentration" = 4.326 jig/L

Genus-level Invertebrate FIC05/2 = 2.55 ng/L

"OPP Invertebrate Benchmark = 2.5 pg/L

0.0

0.1

0.2

0.3

0.4	0.5	0.6

Sensitivity Centile

0.7

0.8

0.9

1.0

Figure 1. Methomyl genus-level acute SD.

Symbols represent Genus Mean Acute Values (GMAVs) calculated using all available data from an Office of Water data analysis in
2015, supplemented the Office of Pesticide Programs (OPP) registration review document for methomyl (U.S. EPA 2010). The
"Criterion Maximum Concentration" is an illustrative example calculated for these analyses.

31


-------
1.1.2.2 Methomyl Chronic Toxicity Data
Chronic Data Sources

Data for methomyl were gathered by OW in 2015 and combined with data from OPP's
registration review document for methomyl (U.S. EPA 2010). The final chronic methomyl
dataset consisted of three NOECs/LOECS for two species across two genera, of which one was
an invertebrate and one was a vertebrate (Table 7).

Table 7. Chronic toxicity data of methomyl to freshwater aquatic organisms.

OW
MDR
Group8

Genus

Species

NOEC
(^g/L)

LOEC
(^g/L)

Endpoint

Reference

D

Daphnia

magna

>0.4

0.9

Number of
young/adult

MRID 00118512; Muska
and Britelli 1982

D

Daphnia

magna

0.700

10.00

Delayed reproduction

MRID 131254; Britelli and
Muska 1982

B

Pimephales

promelas

57.00

117.0

Early lifestage;
reduced survival

MRID 131255; Driscoll
and Muska 1982

B

Pimephales

promelas

76

142

Life cycle test;
growth

MRID 43072101; Strawn
et al. 1993

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important

wannwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Chronic Benchmark Values

The OPP invertebrate chronic benchmark for methomyl is 0.6 |ig/L, which is the MATC for
Daphnia magna, the geometric mean of the NOEC (>0.4 |ig/L) and LOEC (0.9 |ig/L).

The OPP fish chronic benchmark is 57 |ig/L, which is the NOEC for Pimephalespromelas.
GLI Tier II Chronic Value Calculation

Paired acute and chronic toxicity data were available for water flea (Daphnia magna) and
fathead minnow (Pimephales promelas) allowing for the calculation of two Acute-to-Chronic
Ratios (ACR). The water flea (.Daphnia magna) chronic test reported NOAEC and LOAEC
values of 0.700 and 10.00 |ig/L, respectively based on measurements of delayed reproduction
(Britelli and Muska 1982). The fathead minnow (.Pimephales promelas) chronic test reported
NOAEC and LOAEC values of 57.00 and 117.0 |ig/L based on reduced survival (Driscoll and
Muska 1982). Because three experimentally determined ACRs were not available for methomyl,
a Tier I chronic value could not be derived. However, the GLI Tier II approach was used to
calculate the chronic value. Under the GLI Tier II approach, the default value of 18 was used in
place of the third, missing ACR.

32


-------
The paired acute and chronic tests were conducted in different laboratories using water of
different physical characteristics; therefore, OPP's ACR approach was used in the calculations,
which involves the use of the NOAEC values. The chronic Secondary ACR and Secondary
Chronic Value (SCV) calculations are displayed below:

SACR = Geometric Mean of the ACRs

SACR = V12.57 * 36.65 * 18 = 20.24
FAV

SCV =

SACR

9.541

SCV =	= 0.471 ug a. i./L

20.24	^ '

Table 8. Summary and comparison of chronic values for methomyl. Magnitude relative to
ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for each value
comparison. A ratio >1 indicates the OPP value is higher than the OW value. 	

Pesticide

OPP Invertebrate

ALB
(NOAEC) (Year
published, species)

OW Tier II value
(# of ACRs filled,
magnitude relative
to ALB)

OW Invertebrate-only
HCos
(# of ACRs filled,
magnitude relative to
ALB)

Notes

Methomyl

0.6 ng/L
(2020, Daphnia
magna)

0.47 (ig/L

(GLI Tier II; 2 ACRs,
1.3X)

NA

One default ACR
of 18 used to derive
GLI Tier II value.

1.1.2.3 Methomyl References

ECOTOX 12859. Geiger, D.L., Call, D.J., and Brooke L.T. 1988. Acute Toxicities of Organic
Chemicals to Fathead Minnows (Pimephales promelas) Volume IV. Ctr. for Lake Superior
Environ. Stud., Volume 4, Univ. of Wisconsin-Superior, Superior, WI :355.

ECOTOX 6797. Mayer, F.L.J., and Ellersieck, M.R.. 1986. Manual of Acute Toxicity:
Interpretation and Data Base for 410 Chemicals and 66 Species of Freshwater Animals. Resour.
Publ. No. 160, U.S. Department of Interior, Fish and Wildlife Services, Washington, DC 505 p.
http://www.cerc.usgs.gov/pubs/center/pdfDocs/90506-intro.pdf

MRID 00118512. Muska, C.; Brittelli, M. (1982) Chronic Toxicity of Methomyl to Daphnia
magna: Haskell Laboratory Report No. 46-82. (Unpublished study received Dec 3, 1982 under
352-342; submitted by E.I. du Pont de Nemours & Co., Inc., Wilmington, DE; CDL: 071268-B)

MRID 131254. Britelli, M.; Muska, C. 1982. Chronic Toxicity of Methomyl to Daphnia magna:
Haskell Laboratory Report No. 4682; MR No. 0581930. (Unpublished study received Oct 3,
1983 under 352366; submitted by E.I. du Pont de Nemours & Co., Inc., Wilmington, DE;
CDL:251426B)

MRID 131255. Driscoll, R.; Muska, C. 1982. Early Life Stage Toxicity of Methomyl to Fathead
Minnow: Haskell Laboratory Report No. 52882; MR No. 0581930. (Unpublished study received

33


-------
Oct 3, 1983 under 352366; submitted by E.I. du Pont de Nemours & Co., Inc., Wilmington, DE;
CDL:251426C)

MRID 19977. Goodman, N.C. 1978. 48HourLC50A2Ito -Daphnia magna-: Haskell Laboratory
Report No. 16578. (Unpublished study received May 22, 1978 under 352342; submitted by E.I.
du Pont de Nemours & Co., Wilmington, Del.; CDL:233993B).

MRID 4009602. Johnson, W.; Finley, M. 1980. Handbook of Acute Toxicity of Chemicals to
Fish and Aquatic Invertebrates: Resource Publication 137. US Fish and Wildlife Service,
Washington, D.C. 106 p.

MRID 43072101. Strawn, T.; Rhodes, J.; Leak, T. 1993. Full Life Cycle Toxicity of
DPXX1179394 (Methomyl) to the Fathead Minnow (Pimephales promelas) Under Flow
Through Conditions: Final Report: Lab Project Number: 39293: HLO 4793. Unpublished study
prepared by ABC Laboratories, Inc. 3582 p.

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2010. Problem formulation for the environmental fate, ecological risk, endangered
species, and drinking water exposure assessments in support of the registration review of
methomyl. Office of Pesticide Programs. Washington, D.C. July 16, 2010.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

34


-------
1.1.3 Comparison of Aquatic Life Toxicity Values for Propoxur: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA) (U.S.EPA 2024) were gathered from the OPP registration review
document for propoxur (U.S. EPA 2009) and an EPA ECOTOX Knowledgebase search
conducted in 2013. There is no chronic OPP ALB for propoxur, so no chronic value analyses
were conducted for this pesticide.

1.1.3.1 Propoxur Acute Toxicity Data

Acute data were gathered from the OPP registration review document for propoxur (U.S. EPA
2009) and an ECOTOX search conducted in 2013 (see Table 1). The propoxur acute dataset
consisted of 20 acceptable LCsos for a total of 12 species across 11 genera, of which six were
invertebrate species representing five genera. Ranked invertebrate GMAVs are listed in Table 2.

Table 1. Acute toxicity data of propoxur to freshwater aquatic organisms.

()\\





l .( 50/

S\1 AY

(MS/'-)

(IMAY

(MS/'-)



MDR
(Iroup1

(ionus

Species

IX 50

(M8/U

Reference

G

Lumbriculus

variegatus

146,000

146,000

146,000

Brooke 1991

D

Daphnia

magna

3,990





Lejczak 1977

D

Daphnia

magna

27.2

107.0

107.0

Brooke 1991

D

Daphnia

magna

110

Lakotaetal. 1981

D

Daphnia

magna

11





MRID: 00149172; Lamb 1981

F

Aedes

aegypti

150

150

150

Lakotaetal. 1981

F

Pteronarcys

californica

13

15.3

15.3

Sanders and Cope 1968

F

Pteronarcys

californica

18

Mayer and Ellersieck 1986

E

Gammarus

fasciatus

50

50

41.2

Sanders 1972

E

Gammarus

lacustris

34

34

Mayer and Ellersieck 1986

B

Cyprinus

carpio

7,340

7,340

7,340

Lakotaetal. 1981

B

Pimephales

promelas

25,000

14,832

14,832

Mayer and Ellersieck 1986

B

Pimephales

promelas

8,800

Geigeretal. 1988/Call et al. 1989

B

Poecilia

reticulata

2,980

2,277

2,277

Lejczak 1977

B

Poecilia

reticulata

1,740

Lakotaetal. 1981

B

Lepomis

macrochirus

4,800

5,455

5,455

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

6,200

Lamb 1981

A

Oncorhynchus

mykiss

8,200

5,508

5,508

Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

3,700

Lamb 1981

A

Salmo

trutta

2,110

2,110

2,110

Lakotaetal. 1981

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important
warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

35


-------
E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Acute Benchmark Values

The OPP invertebrate acute benchmark for propoxur is 5.5 |ig/L, which is V2 of the D. magna
LC50 of 11 |ig/L cited in Lamb (1981).

The OPP fish acute benchmark is 1,850 ug/L, which is V2 of the 0. mykiss LC50 of 3,700 ug/L
cited in Lamb (1981).

OW Acute Criterion

There is no acute criterion, or criterion maximum concentration (CMC), for propoxur.

An illustrative example calculated for this analysis, using all available data (Table 2) was
conducted.

The HCos calculated following the U.S. EPA (1985) methodology for the eleven genera in the
propoxur dataset was 9.151 |ig/L (Table 3)

Table 2. Propoxur SMAVs and GMAVs

(Ug/L).

(Ion us

Species

S\1 AY

(IMAY

(J.MAY Ritnk

Lumbriculus

variegatus

146,000

146,000

11

Pimephales

promelas

14,832

14,832

10

Cyprinus

carpio

7,340

7,340

9

Oncorhynchus

mykiss

5,508

5,508

8

Lepomis

macrochirus

5,455

5,455

7

Poecilia

reticulata

2,277

2,277

6

Salmo

trutta

2,110

2,110

5

Aedes

aegypti

150.0

150.0

4

Daphnia

magna

107.0

107.0

3

Gammarus

fasciatus

50.00

41.23

2

Gammarus

lacustris

34.00

Pteronarcys

californica

15.30

15.30

1

36


-------
Table 3. Genus-level acute FAV for propoxur calculated following the U.S. EPA (1985)
methodology.

N

11

K;lllk

4

cmay

150.0

lii((,M \V)

5.011

lii{<.M Wr

25.11

r kiN ii

0.3333

>¦ <|i li 1')

0.5774



3

107.0

4.673

21.84

0.2500

0.5000



2

41.23

3,719

13.83

0.1667

0.4082



1

15.3

2,728

7.441

0.0833

0.2887



Sinn:



16.13

68.22

0.833

1.774







s2-

68.37

L =

0.3649

A =

2.214

FAV =

9.151

FAV/2 =

4.6

Genus-Level Invertebrate-only acute HCos

The genus level invertebrate-only acute HCos calculated following the U.S. EPA (1985)
methodology for the five invertebrate genera (Table 3) in the propoxur dataset was 5.324 |ig/L
(Table 4).

Table 3. Propoxur invertebrate SMAVs and GMAVs (^ig/L).

(Ion us

Species

S\1 AY

(IMAY

(J.MAY k:iiik

Lumbriculus

variegatus

146,000

146,000

5

Aedes

aegypti

150.0

150.0

4

Daphnia

magna

107.0

107.0

3

Gammarus

fasciatus

50.00

41.23

2

Gammarus

lacustris

34.00

Pteronarcys

californica

15.30

15.30

1

37


-------
Table 4. Genus-level invertebrate-only acute HCos for propoxur calculated following the

N

Rank

(.MAY

ln(GMAV)

ln(GMAV)2

P=R/(N+1)

sqrt(P)

5

4

150.0

5.011

25.11

0.6667

0.8165



3

107.0

4.673

21.84

0.5000

0.7071



2

41.23

3.719

13.83

0.3333

0.5774



1

15.3

2.728

7.441

0.1667

0.4082



Sum:



16.13

68.22

1.667

2.509







S2 =

34.19

L =

0.3649

A =

1.672

hc05 =

5.324

Table 5. Summary and comparison of acute values for propoxur.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio >1 indicates the OPP value is higher than the OW value.	

Pesticide

OPP Invertebrate ALB
(lowest LCso/2) (Year
published, species)

ALC (FAV/2)

(Year published, # of genera,
magnitude relative to ALB)

OW Genus-level
Invertebrate-only HCos/2
(# of genera, magnitude
relative to ALB)

Propoxur

5.5 ng/L

(2009; D. magna)

4.6 ng/L

(illustrative example calculated for
this analysis, 11 genera, 1.2X)

2.66 ng/L
(5 genera, 2. IX)

Figure 1 shows a genus-level sensitivity distribution for the propoxur dataset. Major taxonomic
groups are delineated by different symbols, and invertebrate genera are identified by name. The
OPP benchmark acute values, illustrative ALC example, and invertebrate-only acute HCos/2 are
included.

38


-------
1,000,000 -

100,000

10,000

CUD
3.

X

o

Q.
O

1,000 -

100

10

•	Arthropod

¦ Salmonid Fish
~ Other Fish
a Other Invertebrate
— • ¦ Genus-level Invertebrate
	OPP Invert. Benchmark

•	- OPP Fish Benchmark

	FAV/2 = "Criterion Maximum Concentration"

Daphnia

i Aedes

Gammarus

Pteronarcys

~

~

OPP Fish Benchmark = 1,850 pg/L

OPP Invertebrate Benchmark = 5.5 [ig/L

FAV/2 = "Criterion Maximum Concentration" = 4.6 pg/L

Genus-level Invertebrate FIC05/2 = 2.7 pg/L

0.0	0.1	0.2	0.3	0.4	0.5	0.6

Sensitivity Centile

0.7

0.8

0.9

1.0

Figure 1. Propoxur genus-level SD.

Symbols represent Genus Mean Acute Values (GMAVs) calculated using all available data from the Office of Pesticide Program's
registration review document for propoxur (U.S. EPA 2009) and an ECOTOX search conducted by Office of Water in 2013.
Propoxur does not have a recommended 304(a) aquatic life criteria. The "Criterion Maximum Concentration" is an illustrative
example calculated for these analyses.

39


-------
1.1.3.2	Propoxur Chronic Toxicity Data

There is no chronic OPP Aquatic Life Benchmark for propoxur, so no chronic analysis was
conducted for this pesticide.

1.1.3.3	Propoxur References

Brooke, L.T. 1991. Results of Freshwater Exposures with the Chemicals Atrazine, Biphenyl,
Butachlor, Carbaryl, Carbazole, Dibenzofuran, 3,3'-Dichlorobenzidine, Dichlorvos, 1,2-
Epoxyethylbenzene (Styrene Oxide), Isophorone, Isopropalin, Ox. Center for Lake Superior
Environmental Studies, University of Wisconsin, Superior, WI, 110 p. ECOREF#: 17138.

Call, D.J., S.H. Poirier, C.A. Lindberg, S.L. Halting, T.P. Markee, L.T. Brooke, N. Zarvan, and
C.E. Northcott. 1989. Toxicity of Selected Uncoupling and Acetylcholinesterase-Inhibiting
Pesticides to the Fathead Minnow (Pimephales promelas). In: D.L. Weigmann (Ed.), Pesticides
in Terrestrial and Aquatic Environments, Proc. Natl. Res. Conf., Virginia Polytechnic Inst, and
State Univ., Blacksburg, VA, 317-336. ECOREF#: 14097.

Geiger, D.L., D.J. Call, and L.T. Brooke. 1988. Acute Toxicities of Organic Chemicals to
Fathead Minnows (Pimephales promelas) Volume IV. Center for Lake Superior Environmental
Studies, University of Wisconsin, Superior, WI, 4, 355 p. ECOREF#: 12859.

Lakota, S., A. Raszka, and I. Kupczak. 1981. Toxic Effect of Cartap, Carbaryl, and Propoxur on
Some Aquatic Organisms. Acta Hydrobiol., 23, (2), 183-190. ECOREF#: 4888.

Lamb, D. 1981. Acute toxicity of technical propoxur (Baygon) to Daphnia magna: Study No.
81-067-01. Unpublished study prepared by Mobay Chemical Corp. 9p.

Lejczak, B. 1977. Effect of Insecticides: Chlorphenvinphos, Carbaryl and Propoxur on Aquatic
Organisms. Pol. Arch. Hydrobiol., 24, (4), 583-591. ECOREF#: 7558.

Mayer, F.L., Jr., and M.R. Ellersieck. 1986. Manual of Acute Toxicity: Interpretation and Data
Base for 410 Chemicals and 66 Species of Freshwater Animals. USDI Fish and Wildlife Service,
Publication No. 160, Washington, DC, 505 p. ECOREF#: 6797.

Sanders, H.O. 1972. Toxicity of Some Insecticides to Four Species of Malacostracan
Crustaceans. Tech. Pap. Bur. Sport Fish. Wildl., 66, 19 p. ECOREF#: 887.

Sanders, H.O., and O.B. Cope. 1968. The Relative Toxicities of Several Pesticides to Naiads of
Three Species of Stoneflies. Limnol. Oceanogr., 13, (1), 112-117.
doi:10.4319/lo,1968.13.1.0112. ECOREF#: 889.

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2009. Registration review: preliminary problem formulation for ecological risk,
environmental fate, endangered species, and drinking water assessments for propoxur. Office of
Pesticide Programs. Washington, D.C. October 16, 2009.

40


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U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

41


-------
1.1.4 Comparison of Aquatic Life Toxicity Values for Malathion: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
(CWA) (U.S.EPA 2024) for malathion were obtained from the 1986 criteria which serves as the
base dataset, supplemented with an update to this data from EPA ECOTOX Knowledgebase in
2010, and with additional data from the U.S. EPA (2010) OPP pesticide effects determination
document that served as the basis for the OPP benchmark concentrations.

1.1.4.1 Malathion Acute Toxicity Data

Acceptable acute data for malathion were obtained from the 1986 criteria which serves as the
base dataset, supplemented with an update to this data from ECOTOX in 2010, and with
additional LCsos reported in Table 4-8 of U.S. EPA (2010), the OPP pesticide effects
determination document that served as the basis for the OPP benchmark concentrations. (See
Table 1.) The final dataset consists of 69 SMAVs and 54 GMAVs, including 36 invertebrate
species representing 29 invertebrate genera. Ranked SMAVs and GMAVs for all invertebrates
included in this analysis are listed in Table 2, below.

Table 1. Acute toxicity data of malathion to freshwater aquatic organisms.

ow





LC50/

SMAV
(^g/L)

GMAV
(^g/L)



MDR
Group8

Genus

Species

EC50
(Hg/L)

Reference

A

Oncorhynchus

clarkii

150





Post and Schroeder 1971

A

Oncorhynchus

clarkii

201





Post and Schroeder 1971

A

Oncorhynchus

clarkii

280





Johnson 1980b; Mayer and
Ellersieck 1986

A

Oncorhynchus

clarkii

174

215.5



Mayer and Ellersieck 1986

A

Oncorhynchus

clarkii

237





Mayer and Ellersieck 1986

A

Oncorhynchus

clarkii

270





Mayer and Ellersieck 1986

A

Oncorhynchus

clarkii

230





Mayer and Ellersieck 1986

A

Oncorhynchus

kisutch

101





Macek and McAllister 1970

A

Oncorhynchus

kisutch

265





Post and Schroeder 1971

A

Oncorhynchus

kisutch

170

168.5

149.1

Johnson 1980b; Mayer and
Ellersieck 1986

A

Oncorhynchus

kisutch

177





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

77





Cope 1965

A

Oncorhynchus

mykiss

68





Cope 1965

A

Oncorhynchus

mykiss

110





Cope 1965

A

Oncorhynchus

mykiss

170





Macek and McAllister 1970

A

Oncorhynchus

mykiss

122

91.2



Post and Schroeder 1971

A

Oncorhynchus

mykiss

93.5





Schoettger 1970

A

Oncorhynchus

mykiss

200





Johnson 1980b; Mayer and
Ellersieck 1986

A

Oncorhynchus

mykiss

94





Mayer and Ellersieck 1986

42


-------
()\\
MIJR

(iioup1

(ionus

Species

I X 50/
I X 50

(M8/U

S\1 AY

(MS/'-)

(IMAY

(MS/'-)

Reference

A

Oncorhynchus

mykiss

4.1





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

138

Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

100

Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

66

Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

80

Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

160

McKimetal. 1987

A

Oncorhynchus

mykiss

250

Li and Fan 1996

A

Salmo

trutta

200

142.1

142.1

Macek and McAllister 1970

A

Salmo

trutta

101

Johnson 1980b; Mayer and
Ellersieck 1986

A

Salvelinus

fontinalis

130

124.9

113.9

Post and Schroeder 1971

A

Salvelinus

fontinalis

120

Post and Schroeder 1971

A

Salvelinus

namaycush

76

103.9

Johnson 1980b; Mayer and
Ellersieck 1986

A

Salvelinus

namaycush

142

Mayer and Ellersieck 1986

B

Perca

flavescens

263

263.0

263.0

Macek and McAllister 1970;
Johnson 1980b; Mayer and
Ellersieck 1986

B

Sander

vitreus

64

64.0

64.0

Johnson 1980b; Mayer and
Ellersieck 1986

B

Oreochromis

mossambica

2,000

2,000

1,181

Mayer and Ellersieck 1986

B

Oreochromis

niloticus

140

140.0

Liongetal. 1988

B

Oreochromis

niloticus x
mossambica

5,880

5,880

Sulaiman et al. 1989

B

Umbra

pygmaea

240

240.0

240.0

Bender and Westman 1976

B

Carassius

auratus

2,610

2,867

2,867

Birge et al. 1979

B

Carassius

auratus

3,150

Birge et al. 1979

B

Cyprinus

carpio

6,590

6,590

6,590

Macek and McAllister 1970;
Johnson 1980b; Mayer and
Ellersieck 1986

B

Danio

rerio

760.2

893.4

893.4

Ton et al. 2006

B

Danio

rerio

1,050

Kumar and Ansari 1984

B

Gila

elegans

15,300

15,300

15,300

Beyers etal. 1994

B

Pimephales

promelas

14,100

12,225

12,225

Geigeretal. 1988

B

Pimephales

promelas

10,600

Geigeretal. 1988

B

Ptychocheilus

lucius

9,140

9,140

9,140

Beyers etal. 1994

B

Ameiurus

melas

12,900

12,285

12,285

Macek and McAllister 1970;
Johnson 1980b; Mayer and
Ellersieck 1986

B

Ameiurus

melas

11,700

Mayer and Ellersieck 1986

B

Ictalurus

punctatus

8,970

8,268

8,268

Macek and McAllister 1970;
Johnson 1980b; Mayer and
Ellersieck 1986

B

Ictalurus

punctatus

7,620

Mayer and Ellersieck 1986

B

Jordanella

floridae

349

349.0

349.0

Hermanutz 1978

43


-------
()\\
MIJR

(iioup1

(ionus

Species

I X 50/
I X 50

(M8/U

S\1 AY

(MS/'-)

(IMAY

(MS/'-)

Reference

B

Gambusia

affinis

700

700.0

700.0

Li and Fan 1996

B

Poecilia

reticulata

840

1,614

1,614

Pickering et al. 1962

B

Poecilia

reticulata

3,100

Maas 1982

B

Morone

saxatilis

24.5

39.9

39.9

Palawski et al. 1985

B

Morone

saxatilis

65

Palawski et al. 1985

B

Lepomis

cyanellus

175

163.2

103.8

Johnson 1980b; Mayer and
Ellersieck 1986

B

Lepomis

cyanellus

146

Mayer and Ellersieck 1986

B

Lepomis

cyanellus

170

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

90

66.7

Pickering et al. 1962

B

Lepomis

macrochirus

120

Maceketal. 1969

B

Lepomis

macrochirus

55

Maceketal. 1969

B

Lepomis

macrochirus

46

Maceketal. 1969

B

Lepomis

macrochirus

131

Eaton 1970

B

Lepomis

macrochirus

89

Eaton 1970

B

Lepomis

macrochirus

103

Macek and McAllister 1970;
Johnson 1980b; Mayer and
Ellersieck 1986

B

Lepomis

macrochirus

20

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

40

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

55

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

84

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

87

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

30

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

110

Mayer and Ellersieck 1986

B

Lepomis

microlophus

170

102.7

Macek and McAllister 1970

B

Lepomis

microlophus

62

Johnson 1980b; Mayer and
Ellersieck 1986

B

Micropterus

salmoides

50

152.7

152.7

Pickering et al. 1962

B

Micropterus

salmoides

285

Macek and McAllister 1970;
Johnson 1980b; Mayer and
Ellersieck 1986

B

Micropterus

salmoides

250

Mayer and Ellersieck 1986

C

Bufo

woodhousei
fowleri

420

420.0

420.0

Sanders 1970; Mayer and
Ellersieck 1986

C

Pseudacris

triseriata

200

200.0

200.0

Sanders 1970; Mayer and
Ellersieck 1986

C

Rana

boylii

2,137

2,137

2,137

Sparling and Fellers 2007

C

Xenopus

laevis

10,900

10,900

10,900

Snawder and Chambers 1989

D

Ceriodaphnia

dubia

0.5

0.5

0.5

Foster etal. 1998

D

Daphnia

magna

1.0

2.4

2.1

Johnson 1980b

D

Daphnia

magna

1.8

Kikuchi et al. 2000

D

Daphnia

magna

1.6

Maas 1982

44


-------
()\\
MIJR

(iioup1

(ionus

Species

I X 50/
I X 50

(M8/U

S\1 AY

(MS/'-)

(IMAY

(MS/'-)

Reference

D

Daphnia

magna

33





Hermens et al. 1984

D

Daphnia

magna

0.90

Ren et al. 2007

D

Daphnia

magna

2.2

MRID 41029701; Burgess
1989

D

Daphnia

pulex

2

1.9

Cope 1966

D

Daphnia

pulex

1.8

Sanders and Cope 1966;
Johnson 1980b

D

Simocephalus

serralatus

3

2.5

2.7

Cope 1966

D

Simocephalus

serralatus

3.5

Sanders and Cope 1966;
Johnson 1980b

D

Simocephalus

serralatus

6.2

Sanders and Cope 1966

D

Simocephalus

serralatus

0.59

MRID 40098001; Mayer and
Ellersick 1986

D

Simocephalus

vetulus

2.9

2.9

Olvera-Hernandez et al. 2004

D

Cypridopsis

vidua

47

47.0

47.0

MRID 40098001; Mayer and
Ellersick 1986

E

Asellus

brevicaudus

3,000

3,000

3,000

Sanders 1972; Johnson 1980b;
Mayer and Ellersieck 1986

E

Gammarus

fasciatus

0.76

0.7

1.0

Sanders 1972; Johnson 1980b;
Mayer and Ellersieck 1986

E

Gammarus

fasciatus

0.90

Sanders 1972; Mayer and
Ellersieck 1986

E

Gammaras

fasciatus

0.50

Sanders 1972; Mayer and
Ellersieck 1986

E

Gammaras

lacustris

1.62

1.4

Gaufinetal. 1965

E

Gammaras

lacustris

1.0

Sanders 1969

E

Gammaras

lacustris

1.8

MRID 05009242; Sanders
1969

E

Orconectes

nais

180

180.0

180.0

Sanders 1972; Johnson 1980b;
Mayer and Ellersieck 1986

E

Palaemonetes

kadiakensis

12

32.6

24.8

Sanders 1972; Mayer and
Ellersieck 1986

E

Palaemonetes

kadiakensis

90

Sanders 1972; Johnson 1980b;
Mayer and Ellersieck 1986

E

Palaemonetes

kadiakensis

32

Mayer and Ellersieck 1986

E

Palaemonetes

pugio

8.94

18.9

Key and Fulton 2006

E

Palaemonetes

pugio

39.92



Key and Fulton 2006

E

Procambaras

clarkii

49,170

49,170

49,170

Hoick and Meek 1987

F

Dranella

grandis

100

100.0

100.0

Gaufinetal. 1965

F

Lestes

congener

10

10.0

10.0

Johnson 1980b; Mayer and
Ellersieck 1986

F

Claassenia

sabulosa

2.8

2.8

2.8

Sanders and Cope 1968;
Johnson 1980b; Mayer and
Ellersieck 1986

F

Isoperla

sp.

0.69

0.7

0.7

Johnson 1980b; Mayer and
Ellersieck 1986

45


-------
()\\
MDR

(iioup1

(ionus

Species

I X 50/
I X 50

(M8/U

S\1 AY

(MS/'-)

(IMAY

(MS/'-)

Reference

F

Pteronarcella

badia

1.1

3.9

3.9

Sanders and Cope 1968;
Johnson 1980b; Mayer and
Ellersieck 1986

F

Pteronarcella

badia

6.2

Mayer and Ellersieck 1986

F

Pteronarcella

badia

8.8

Mayer and Ellersieck 1986

F

Pteronarcys

californicus

10

10.0

10.0

Sanders and Cope 1968;
Johnson 1980b; Mayer and
Ellersieck 1986

F

Peltodytes

sp.

1,000

1,000

1,000

Federle and Collins 1976

F

Arctopsyche

grandis

32

32.0

32.0

Gaufinetal. 1965

F

Hydropsyche

californica

22.5

22.5

10.6

Gaufinetal. 1965

F

Hydropsyche

sp.

5

5

MRID 40098001; Mayer and
Ellersick 1986

F

Limnephilus

sp.

1.3

1.3

1.3

Johnson 1980b; Mayer and
Ellersieck 1986

F

Atherix

sp.

385

385.0

385.0

Johnson 1980b

F

Chironomus

plumosus

8.4

8.4

72.2

Vedamanikam 2009

F

Chironomus

dilutus

620

620.0

Hansen and Kawatski 1976

F

Notonecta

undulata

80

80.0

80.0

Federle and Collins 1976

H

Limnodrilus

sp.

16,700

16,700

16,700

Whitten and Goodnight 1966

H

Lumbriculus

variegatus

20,500

20,500

20,500

Bailey and Liu 1980

H

Tubifex

sp.

16,700

16,700

16,700

Whitten and Goodnight 1966

G

Elliptio

icterina

32,000

32,000

32,000

Keller and Ruessler 1997

G

Lampsilis

straminea
claibornen

24,000

24,000

25,923

Keller and Ruessler 1997

G

Lampsilis

subangulata

28,000

28,000

Keller and Ruessler 1997

G

Utterbackia

imbecillis

215,000

108,654

108,654

Keller and Ruessler 1997

G

Utterbackia

imbecillis

219,000

Keller and Ruessler 1997

G

Utterbackia

imbecillis

40,000

Keller and Ruessler 1997

G

Utterbackia

imbecillis

74,000

Keller and Ruessler 1997

G

Villosa

lienosa

109,000

96,382

124,133

Keller and Ruessler 1997

G

Villosa

lienosa

111,000

Keller and Ruessler 1997

G

Villosa

lienosa

74,000

Keller and Ruessler 1997

G

Villosa

villosa

142,000

159,875

Keller and Ruessler 1997

G

Villosa

villosa

180,000

Keller and Ruessler 1997

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important
warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

46


-------
OPP Acute Benchmark Values

The OPP invertebrate acute benchmark for malathion is 0.049 |ig/L, which is one half of the
LC50 of 0.098 |ig/L for D. magna.

The OPP fish acute benchmark for malathion is 2.05 |ig/L, which is one half of the LC50 of 4.1
|ig/L for rainbow trout (Oncorhynchus mykiss), the lowest LC50 of any fish species.

OW Acute Criterion

The 1986 acute criterion, or CMC, for malathion of 0.1 |ig/L was not calculated using calculated
the U.S. EPA (1985) methodology, as it pre-dates the Guidelines. Rather, it was calculated by
dividing the effect acute LC50 for G. lacustrus, G. fasciatis, and D. magna, which were all
approximately 1 |ig/L, by an application factor of ten (U.S. EPA 1976 - EPA Red Book).

Genus-Level Invertebrate-only Acute HC05

The acute HC05 calculated from invertebrate-only GMAVs shown in Table 2 was calculated
following the U.S. EPA (1985) methodology is 0.8360 |ig/L (Table 3).

Table 2. Malal

thion Invertebrate SMAVs and GMAVs (jug/L).

Genus

Species

S.MAN'

GMAV

GMAV Rank

Villosa

lienosa

96,382

124,133

29

Villosa

villosa

108,653

Utterbackia

imbecillis

108,653

108,653

28

Procambarus

clarkii

49,170

49,170

27

Elliptic)

icterina

32,000

32,000

26

Lampsilis

straminea claibornen

24,000

25,923

25

Lampsilis

subangulata

28,000

Lumbriculus

variegatus

20,500

20,500

24

Limnodrilus

sp.

16,700

16,700

23

Tubifex

sp.

16,700

16,700

22

Asellus

brevicaudus

3,000

3,000

21

Peltodytes

sp.

1,000

1,000

20

Atherix

sp.

385.0

385.0

19

Orconectes

nais

180.0

180.0

18

Drunella

grandis

100.0

100.0

17

Notonecta

undulata

80.00

80.00

16

Chironomus

plumosus

8.400

72.17

15

Chironomus

dilutus

620.0

Cypridopsis

vidua

47.00

47.00

14

Arctopsyche

grandis

32.00

32.00

13

Palaemonetes

pugio

18.89

24.81

12

Palaemonetes

kadiakensis

32.57

Hydropsyche

californica

22.50

22.50

11

Lestes

congener

10.00

10.00

10

Pteronarcys

californicus

10.00

10.00

9

Pteronarcella

badia

3.915

3.915

8

Claassenia

sabulosa

2.800

2.800

7

Simocephalus

vetulus

2.900

2.687

6

Simocephalus

serrulatus

2.489

47


-------
Genus

Species

SMAV

GMAV

GMAV Rank

Daphnia

magna

2.394

2.131

5

Daphnia

pulex

1.897

Linmephilus

sp.

1.300

1.300

4

Ceriodaphnia

dubia

1.294

1.294

3

Gammarus

lacustris

1.429

0.9995

2

Gammarus

fasciatus

0.6993

Isoperla

sp.

0.6900

0.6900

1

Table 3. Genus-level invertebrate-only acute HCos for malathion calculated following the

U.S. EPA

1985) met

hodolog

y-

N

Rank

GMAV

ln(GMAV)

ln(GMAV)2

P=R/(N+1)

sqrt(P)

29

4

1.3

0.262

0.07

0.1333

0.3651



3

1.294

0.258

0.07

0.1000

0.3162



2

0.9995

-0.001

0.00

0.0667

0.2582



1

0.69

-0.371

0.138

0.0333

0.1826



Sum:



0.15

0.27

0.3333

1.1221







S2 =

14.44

L =

-1.029

A =

-0.179

HCos =

0.8360

Table 4. Summary and comparison of acute values for malathion by approach.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value.	

Pesticide

OPP Invertebrate ALB
(lowest LCso/2) (Year
published, species)

OW ALC (FAV/2) (Year
published, # of genera,
magnitude relative to ALB)

OW Genus-level
Invertebrate-only HCos/2
(# of genera, magnitude
relative to ALB)

Malathion

0.049 (ig/L
(2016; C. dubia)

0.1 ng/L

(1986, "Gold Book", 0.49X)

0.418 (ig/L
(29 genera, 0.12X)

Figure 1 shows a genus-level sensitivity distribution for the malathion dataset. Major taxonomic
groups are delineated by different symbols, and invertebrate genera are identified by name. Lines
denoting the CMC, invertebrate acute HCos/2, and OPP acute benchmark values are also
included.

48


-------
1,000,000.00

100,000.00

10,000.00

^ 1,000.00

tLfl

3
c

o 100.00

TO

10.00

1.00

0.10 -L-

0.01

•

Arthropod

o

Other Invertebrate

A

Mollusk

¦

Salmonid Fish

~

Other Fish

~

Amphibian



CMC

Genus-level Invertebrate
OPP Invert. Benchmark

	

OPP Fish Benchmark

Villosa v
X

Utterbackia A A

Lumbriculus ¦

Limnodrilus

Tubifex

Lampsilis

~

~ • Asellus

Chironomus

Drunella

Arctopsyche

\



Orconectes

~

~ •

~ ~



~

~

Peltodytes

Atherix

~



n i	• K	^Notonecta

Palaemonetes •	x\

Cypridopsis

Pteronarcys# # #H d he
Simocephalus	7 r 7

Daphnia	Lestes

		

^ . ... Claassenia
• Limnephilus

**- CeriodaDhnia

Genus-level Invertebrate FIC05/2 = 0.4180 ng/L

N Gammarus
Isoperla

FAV/2 = Criterion Maximum Concentration (CMC) = 0.1 |ig/L

^—. OPP Invertebrate Benchmark = 0.049 ng/L

o.o

o.i

0.2

0.3

0.4	0.5	0.6

Sensitivity Centile

0.7

0.8

0.9

1.0

Figure 1. Malathion acute genus-level SD.

Symbols represent Genus Mean Acute Values (GMAVs) calculated using all available data from the malathion ALC (U.S. EPA
1986), the Office of Pesticide Program's registration review document for malathion (U.S. EPA 2010), and an ECOTOX search
conducted by Office of Water in 2010.

49


-------
1.1.4.2 Malathion Chronic Toxicity Data

For chemicals lacking sufficient chronic data to satisfy the minimum taxonomic data
requirements, such as malathion, the EPA Office of Water (OW) calculates the final chronic
value (FCV) as the final acute value (FAV) divided by the final acute-to chronic ratio (FACR).
The Office of Pesticide Programs (OPP) will also apply ACRs to acute data for sensitive
taxonomic groups to calculate chronic benchmarks when chronic test data are not available.
Calculations of ACRs following OPP and OW methodologies were conducted, and the effects of
these ACRs on the resulting OPP and OW chronic values were compared.

Chronic Data Sources

The data sources for this analysis were a 2010 ECOTOX search for malathion and the OPP-
authored malathion effects determination reports for delta smelt and California tiger salamander
(U.S. EPA 2010) and California red legged frog (U.S. EPA 2007). Many values were reported
across all three data sources.

ACR Calculations

ACR calculations following OW and OPP methodologies are described below. All available
chronic malathion data are shown in Table 5. All available acute data for species that also have
chronic data are shown in Table 6. Table 7 lists all ACRs by species and calculation method.

Invertebrate ACRs

Daphnia magna

An ACR for D. magna could not be calculated following the Guidelines requirements, as there
were no acute and chronic tests for this species conducted in the same study or laboratory
(Stephan et al. 1985). However, invertebrates are the most sensitive taxonomic group to
malathion, and D. magna is the only invertebrate species with chronic malathion data. In
addition, the Guidelines requires ACR from at least three families; including at least one fish,
one invertebrate, and one acutely sensitive species. For these reasons, a D. magna ACR was
calculated for this analysis.

The "qualitative" OW D. magna ACR is 5.942, calculated as the geometric mean of the two
acute values identified as ECsos (Johnson 1980b, Kikuchi et al. 2000) divided by the geometric
mean of the two chronic tests with MATCs (Biesinger 1973, Blakemore and Burgess 1990). The
acceptable registrant submitted acute study by Burgess (1989) was not included in this
calculation because it was a formulation (57% active ingredient), and below the 80% purity
threshold recommended in the Guidelines (U.S. EPA 1985).

The ACR calculated following the OPP approach is 13.22, calculated as the geometric mean of
all 48-hour acute values divided by the geometric mean of the NOECs from all chronic studies.
The OPP ACR guidance offers flexibility when multiple acceptable acute and chronic values are
available for the same species (U.S. EPA 2005).

50


-------
Vertebrate (Fish) ACRs

Oncorhynchus mykiss

An ACR for this species could not be calculated following the OW approach. Cohle (1989)
reported test results following a 97-day ELS test in an unpublished report, but there are no acute
studies conducted in the same laboratory.

Following the rationale used for D. magna, the OPP ACR for 0. mykiss is 4.074, calculated as
the geometric mean of all acute tests listed in Table 2 (all of which were 96 hours), divided by
the NOEC reported by Cohle (1989).

Gila elegans

An ACR for this species could not be calculated following the OW approach. Beyers et al.
(1994) performed an early life stage (ELS) chronic test and a static-renewal acute test. Although
the acute and chronic tests were performed in the same laboratory, the Guidelines (U.S. EPA
1985) specifies that acute test data should also be from a flow-through study (except for
Daphnids, where static acute tests are acceptable). The ACR following the OPP approach is
15.46, calculated as the acute value of 15,300 ng/L from Beyers et al. (1994) divided by the
NOEC of 990 |ag/L from ELS test performed in the same laboratory.

Pimephales promelas

An ACR for this species could not be calculated following the OW approach. Mount and
Stephan (1967) performed an acute and chronic test in the same laboratory, but the acute test was
static. The OPP ACR fori5, promelas is 63.18, calculated as the geometric mean of the three
acute flow-through tests listed in Table 6 divided by the NOEC of the Mount and Stephan
(1967) chronic test.

Ptychocheilus lucius

An ACR for this species could not be calculated following the OW approach. Beyers et al.
(1994) performed an early life stage (ELS) chronic test and a static-renewal acute test. Although
the acute and chronic tests were performed in the same laboratory, the Guidelines (U.S. EPA
1985) states that acute test data must also be from a flow-through study (except for Daphnids,
where static acute tests are acceptable). Also worth noting is the study authors reported that the
water for the acute and chronic tests was inadvertently aged differently, with the acute tests
having higher dissolved oxygen and pH, and lower hardness and alkalinity, than the chronic
tests. The ACR following the OPP approach is 5.440, calculated as the acute value of 9,140 ng/L
from Beyers et al. (1994) divided by the NOEC of 1,680 ng/L from ELS test performed in the
same laboratory.

Jordanella floridae

The OW ACR for J. floridae is 15.98, calculated as the acute value from a flow-through test
conducted by Hermanutz (1978) divided by the MATC for the survival endpoint from a life
cycle test conducted by Hermanutz (1978). The OPP ACR for J. floridae is 40.58, calculated as
the acute value from a flow-through test conducted by Hermanutz (1978), divided by the NOEC
for the growth endpoint from a life cycle test conducted by Hermanutz (1978).

51


-------
Lepomis macrochirus

The OW ACR for L. macrochirus is 15.27, calculated as the geometric mean of two flow
through acute tests conducted by Eaton (1970) divided by the MATC of an ELS test conducted
in the same laboratory (Eaton 1970). The OPP ACR is 21.60, calculated as the geometric mean
of the Eaton (1970) acute tests divided by the NOEC of the Eaton (1970) ELS test.

Oryzias latipes

An OW ACR could not be calculated for O. latipes. An OPP ACR of 48.60 was calculated as the
ratio of the definitive acute value 9,700 |ag/L divided by the NOEC of 199.6 |ag/L from Beaman
et al. (1999). This ACR is considered qualitative and is not used to calculate a final ACR for this
chemical.

Oreochromis mossambica

An OW ACR could not be calculated because there were no paired acute and chronic tests. An
OPP ACR was also not calculated for this species because there was no definitive NOEC for the
chronic test. If a NOEC of <500 |ag/L is used as the denominator, the ACR would be >1.523,
calculated as the geometric mean of the two definitive acute values divided by the NOEC.
Because this is a small greater than value, it is not included in the final ACR calculations.

Channa punctata

An OW ACR could not be calculated for this species. An acute (Pandey et al. 2005) and chronic
(Pandey et al. 1981) test were conducted by the same author, but it could not be confirmed if the
tests were performed in the same laboratory. Because the chronic test duration was only 15 days,
an OW ACR would not have been calculated even if the acute and chronic tests were from the
same laboratory. An OPP ACR of 4.234 was calculated as the geometric mean of the four acute
tests divided by the NOEC from Pandey et al. (1981). This ACR is considered qualitative and is
not used to calculate a final ACR for this chemical.

Cyprinodon variegatus

The OW ACR is 8.5, calculated as the acute value of 51 |ig/L reported in Hansen and Parish
(1977) and Parish et al. (1977) divided by the paired chronic MATC of 6 |ig/L. The OPP ACR of
12.75 is calculated by the Hansen and Parish (1977) and Parish et al. (1977) acute value divided
by the paired NOEC of 4 |ig/L.

Final ACRs

The final ACRs (FACRs) for the two approaches, expressed as the geometric mean of all
available ACRs, is 10.54 following the OW approach, and 15.42 following the OPP approach.
The OW FACR consists of ACRs for J. jloridae, L. macrochirus, and C. variegatus. The OW
FACR also includes the qualitative ACR for D. magna that could not be calculated following the
OW methodology, but which is included because it is the only invertebrate species for which
chronic data are available. The OPP FACR consists of ACRs for the species listed above, as well
as 0. mykiss, G. elegans, P. promelas, and P. lucius. Qualitative ACRs for 0. latipes and C.
punctata were not included here because of chronic test duration. Table 7 lists all final and
invertebrate only ACRs.

52


-------
The Guidelines notes that a range of ACRs that is greater than 10-fold may indicate a potential
cause for concern. ACRs calculated following the OPP approach vary by a factor of 11.6. While
there is no clear relationship between the size of ACRs and acute sensitivity for this chemical,
the largest ACR is for the acutely insensitive fish species P. promelas. A second option would be
to exclude the P. promelas ACR of 63.18 from the OPP FACR calculation, which would result
in a FACR of 12.61 (Table 7).

Comparison of Freshwater Chronic Values for Malathion
OPP Chronic Benchmarks

For malathion, the freshwater invertebrate chronic benchmark is 0.06 |ig/L (Table 8), the NOEC
of a registrant submitted D. magna test (Blakemore and Burgess 1990). The freshwater fish
chronic benchmark is 8.6 |ig/L, the NOEC for the growth endpoint reported in Hermanutz
(1978).

OW Freshwater Chronic Values - All Taxa

Final chronic concentrations following the ACR methodology are calculated by dividing the final
acute value by a final ACR (FACR). For malathion, a freshwater FAV of 0.8927 |ig/L was
calculated from the 53 genera included in the 2010 ECOTOX update. The final chronic value
following the OW-ACR approach (including the D. magna ACR that deviated from the
Guidelines), is 0.0847 |ag/L (0.8927 |ag/L ^ 10.54), and the final chronic value following the
OPP-ACR approach is 0.0579 jig/L (0.8927 jig/L - 15.42). The OPP FACR following the
second option (excluding the ACR of 63.18 for P. promelas) is 0.0708 (0.8927 |ag/L 12.61).

OW Freshwater Chronic Values - Invertebrate Taxa

Final chronic concentrations for the invertebrate-only malathion dataset are calculated by
dividing the final invertebrate acute value by an ACR. This dataset was comprised of acute
invertebrate test data found in the 2010 ECOTOX update and the 2010 effects determination
report U.S. EPA (2010). The resulting acute HCos calculated from the 29 invertebrate genera
using the Guidelines methology was 0.8360 ng/L. The final invertebrate chronic value following
the OW-ACR approach (using the D. magna ACR that deviated from the Guidelines) is 0.1407
Hg/L (0.8360 |ag/L ^ 5.942), and the final chronic value following the OPP-ACR approach is
0.0632 |ag/L (0.8360 |ag/L ^ 13.22). Table 8 lists all chronic values calculated following the
different approaches.

53


-------
Table 5. Chronic test data for malathion.

All concentrations expressed as ng/L.	

Genus

Species

NOEC

LOEC

MATC

Reference

Test data re

)ortcd in:

OPP
Classification

Notes"

2010
ECOTOX
Search

2007
OPP

2010 OPP

Invertebrates

Daphnia

magna

0.57

0.76

0.658

Biesinger 1973

X







OW,OPP

Daphnia

magna

0.06

0.1

0.077

Blakemore and
Burgess 1990



Table 23

Table 4-10

Acceptable

OW,OPP

Daphnia

magna

0.15

NR

0.150

Dortland 1980



Table 23



Qualitative

OPP

Vertebrates

Oncorhynchus

mykiss

21

44

30.40

Cohle 1989



Table 20

Table 4-7

Qualitative

ELS; OPP























Gila

elegans

990

2,000

1,407

Beyers et al.
1994

X







ELS; OPP























Pimephales

promelas

200

580

340.6

Mount and
Stephan 1967

X







LC; OPP























Ptychocheilus

lucius

1680

3,510

2,428

Beyers et al.
1994

X







ELS; OPP























Jordanella

floridaeh

19.3

25

21.83

Hermanutz 1978

X







LC; OW

Jordanella

floridaec

8.6

10.9

9.682

Hermanutz 1978



Table 20

Table 4-7

Quantitative

LC; OPP























Lepomis

macrochirus

5

10

7.071

Eaton 1970

X







ELS; OW,OPP























Oryzias

latipes

199.6

798

399.2

Beaman et al.
1999



Table 20

Table 4-7

Qualitative

14d; OPP























Oreochromis

mossambica

ND

500



Sweilum 2006



Table 20

Table 4-7

Qualitative

168d























Channa

punctata

500

ND



Pandey et al.
1981



Table 20

Table 4-7

Qualitative

15d; OPP























Cyprinodon

variegatus

4

9

6

Hansen and
Parrish 1977

X







ELS; OW,OPP

a LC-life cycle test, ELS-early life stage test, OW - used in OW-ACR calculation, OPP - used in OPP-ACR calculation

54


-------
Table 6. Acute malathion test data for species with chronic test data. All concentrations expressed as ng/L.

(iCIIIIS

Species

i:c 50

or
l.( 50

Reference

Tcsl riala reported in:

OPP
Classification

\o(cs;l

2010

i'.cotox

Search

200"7 ()l>l>

2010 OPP

Invertebrates

Daphnia

magna

1.0

Johnson 1980b

X

Table 22

Table 4-8

Acceptable

EC50; S,U; OW, OPP

Daphnia

magna

1.6

Maas 1982

X







LC50; S,U; OPP

Daphnia

magna

33

Hermensetal. 1984

X







LC50; S,M; OPP

Daphnia

magna

1.8

Kikuchi et al. 2000

X







EC50; S,U; OW,OPP

Daphnia

magna

0.90

Ren et al. 2007

X







LC50; S,U; OPP

Daphnia

magna

2.20

Burgess 1989



Table 22

Table 4-8

Acceptable

57% a.i.; OPP

Daphnia

magna

0.098

Raweshetal. 1975



Table 22



Qualitative -
2007; Invalid -
2010

Not used, 24hr.

Daphnia

magna

1.7

ECOREF 6449



Table 22



Qualitative

OPP

Daphnia

magna

2.35

Cano et al. 1999



Table 22



Qualitative

Not used, 24 hr.

Vertebrates

Oncorhynchus

mykiss

77

Cope 1965

X







S,U; OPP

Oncorhynchus

mykiss

68

Cope 1965

X







S,U; OPP

Oncorhynchus

mykiss

110

Cope 1965

X







S,U; OPP

Oncorhynchus

mykiss

170

Macek and McAllister
1970

X



Table 4-3



S,U; OPP

Oncorhynchus

mykiss

122

Post and Schroeder 1971

X







S,U; OPP

Oncorhynchus

mykiss

93.5

Schoettger 1970

X







S,U; OPP

Oncorhynchus

mykiss

200

Johnson 1980b; Mayer and
Ellersieck 1986

X







S,U; OPP

Oncorhynchus

mykiss

94

Mayer and Ellersieck 1986

X







S,U; OPP

Oncorhynchus

mykiss

4.1

Mayer and Ellersieck 1986

X

Table 19

Table 4-3

Qualitative

S,U; OPP

Oncorhynchus

mykiss

138

Mayer and Ellersieck 1986

X







S,U; OPP

Oncorhynchus

mykiss

100

Mayer and Ellersieck 1986

X







S,U; OPP

Oncorhynchus

mykiss

66

Mayer and Ellersieck 1986

X







S,U; OPP

Oncorhynchus

mykiss

80

Mayer and Ellersieck 1986

X







S,U; OPP

Oncorhynchus

mykiss

160

McKimetal. 1987

X

Table 19



Qualitative

S,U; OPP

Oncorhynchus

mykiss

250

Li and Fan 1996

X







S,U; OPP

Oncorhynchus

mykiss

32.8

Animal Biology Lab 1968





Table 4-3

Acceptable

OPP



Gila

elegans

15,300

Beyers etal. 1994

X







R,M; OPP



55


-------
(iCIIIIS

Species

i:c 50

or
l.( 50

Reference

Test diilii reported in:

OPP
Cliissiriciilion

Nolev'

2010

i'.cotox

Sesirch

200"7 ()l>l>

2010 OPP

Pimephales

promelas

16,000

Pickering et al. 1962

X







S,U

Pimephales

promelas

23,000

Pickering et al. 1962

X







s,u

Pimephales

promelas

9,000

Mount and Stephan 1967

X







s,u

Pimephales

promelas

13,500

Bender 1969a

X







F,U; OPP

Pimephales

promelas

9,700

Bender 1969b

X







s,u

Pimephales

promelas

8,650

Macek and McAllister
1970; Johnson 1980b;
Mayer and Ellersieck 1986

X

Table 19

Table 4-3

Acceptable

s,u

Pimephales

promelas

11,000

Mayer and Ellersieck 1986

X







s,u

Pimephales

promelas

14,100

Geigeretal. 1988

X

Table 19



Qualitative

F,M; OPP

Pimephales

promelas

10,600

Geigeretal. 1988

X







F,M; OPP

Pimephales

promelas

12,500

Henderson and Pickering
1958



Table 19



Qualitative





Ptychocheilus

lucius

9,140

Beyers etal. 1994

X







R,M; OPP



















Jordanella

floridae

349

Hermanutz 1978

X

Table 19



Qualitative

F,M; OW,OPP

Jordanella

floridae

280

Hermanutz et al. 1985



Table 19



Qualitative





Lepomis

macrochirus

90

Pickering et al. 1962

X







S,U

Lepomis

macrochirus

120

Macek etal. 1969

X







S,U

Lepomis

macrochirus

55

Macek etal. 1969

X







S,U

Lepomis

macrochirus

46

Macek etal. 1969

X







S,U

Lepomis

macrochirus

131

Eaton 1970

X







F,U; OW,OPP

Lepomis

macrochirus

89

Eaton 1970

X







F,U; OW,OPP

Lepomis

macrochirus

103

Macek and McAllister
1970; Johnson 1980b;
Mayer and Ellersieck 1986

X



Table 4-3

Qualitative

s,u

Lepomis

macrochirus

20

Mayer and Ellersieck 1986

X

Table 19

Table 4-3

Qualitative

s,u

Lepomis

macrochirus

40

Mayer and Ellersieck 1986

X



Table 4-3

Qualitative

s,u

Lepomis

macrochirus

55

Mayer and Ellersieck 1986

X



Table 4-3

Qualitative

s,u

Lepomis

macrochirus

84

Mayer and Ellersieck 1986

X







s,u

Lepomis

macrochirus

87

Mayer and Ellersieck 1986

X







s,u

Lepomis

macrochirus

30

Mayer and Ellersieck 1986

X

Table 19

Table 4-3

Qualitative

s,u

Lepomis

macrochirus

110

Mayer and Ellersieck 1986

X







s,u

Lepomis

macrochirus

336.6

ECOTOX 77525



Table 19



Qualitative



56


-------
(iCIIIIS

Species

i:c 50

or
l.( 50

Reference

Test diilii reported in:

OPP
Cliissiriciilion

Nolev'

2010

i'.cotox

Sesirch

200"7 OPP

2010 OPP

Lepomis

macrochirus

48

Gries and Purghart 2001





Table 4-3

Acceptable





Oryzias

latipes

<2,800

ECOTOX 8977



Table 19



Qualitative



Oryzias

latipes

9,700

ECOTOX 89099



Table 19



Qualitative

OPP



Oreochromis

mossambica

<2,400

Mayer and Ellersieck 1986

X







s,u

Oreochromis

mossambica

2,000

Mayer and Ellersieck 1986

X

Table 19

Table 4-3

Qualitative

s,u

Oreochromis

mossambica

290.1

Liuetal. 1983



Table 19



Qualitative





Channa

punctata

3890

ECOTOX 11888



Table 19



Qualitative



Channa

punctata

894

Kaur and Toor 1995



Table 19



Qualitative



Channa

punctata

874

Kaur and Toor 1995



Table 19



Qualitative



Channa

punctata

6610

Pandey et al. 2005



Table 19



Qualitative

OPP



Cyprinodon

variegatus

51

Hansen and Parrish 1977

X







F,M; OW,OPP

Cyprinodon

variegatus

33

Bowman 1989

X







F,U

aF - flow through, R - renewal, S - static, M - measured, U - unmeasured, OW - used in OW-ACR calculation, OPP - used in OPP-ACR calculation

57


-------
Table 7. ACRs by species and calculation method.

Genus

Species

ACR

Notes

OW-ACR

OPP-ACR

Invertebrates

Daphnia

magna

5.942a

13.22

OW ACR following Guidelines could not be calculated.

Vertebrates

Oncorhynchus

mykiss

N/A

4.074



Gila

elegans

N/A

15.46



Pimephales

promelas

N/A

63.18



Ptychocheilus

lucius

N/A

5.440



Jordanella

floridae

15.98

40.58



Lepomis

macrochirus

15.27

21.60



Oryzias

latipes

N/A

48.60

OPP ACR should be considered qualitative due to chronic test duration (14-d)

Oreochromis

mossambica

N/A

N/A

ACR not calculated because no NOAEC was available

Channa

punctata

N/A

4.234

OPP ACR should be considered qualitative due to chronic test duration (15 -d)

Cyprinodon

variegatus

8.5

12.75





All Taxa FACR (OPP Option l)b

10.54

15.42



All Taxa FACR (OPP Option 2)c

10.54

12.61



All Invertebrates

5.942

13.22



a An ACR following the Guidelines could not be calculated, as there were no acute and chronic studies from same study/laboratory/test water.

The resulting qualitative ACR was included because no other ACRs for invertebrate taxa were available.
b ~ OPP all taxa ACR does not include qualitative ACRs for O. latipes or C. punctata. OW all taxa ACR does include the "qualitative" D. magna ACR.
0 - Does not include ACR for P. promelas ((>10x spread and acutely insensitive).

58


-------
Table 8. Summary and comparison of freshwater chronic values for malathion.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value.

Pesticide

OPP Most Sensitive
ALB
(Year published,
species)

OW Illustrative ALC
(# of ACRs filled, magnitude
relative to ALB)

OW Invertebrate-only HCos/2
(# of ACRs filled, magnitude
relative to ALB)

Malathion

0.06 ng/L

(2016, Daphnia magna)

0.08 ng/L

(illustrative ALC example calculated
for this analysis; 0.75X)

0.14 (ig/L

(See Table 7 for ACRs, 0.43X)

1.1.4.3 Malathion References

ECOREF 6449: Dortland, R.J. 1980. Toxicological Evaluation of Parathion and Azinphosmethyl
in Freshwater Model Ecosystems. Versl. Landbouwkd. Onderz., 898: 1-112.

ECOTOX 11888: Haider, S., andR.M. Inbaraj (1986). Relative Toxicity of Technical Material
and Commercial Formulation of Malathion and Endosulfan to a Freshwater Fish, Channel
punctatus (Bloch). Ecotoxicol. Environ. Saf., 11, (3), 347-351. doi: 10.1016/0147-
6513(86)90107-7. ECOREF#: 11888.

ECOTOX 77525: Van der Schalie, W.H., T.R. Shedd, M.W. Widder, and L.M. Brennan (2004).
Response Characteristics of an Aquatic Biomonitor Used for Rapid Toxicity Detection. J. Appl.
Toxicol. 24(5): 387-394. doi:10.1002/jat,1028.

ECOTOX 89099: Wolfe, M.F., D.E. Hinton, and J.N. Seiber (1995). Aqueous Sample
Preparation for Bioassay Using Supercritical Fluid Extraction. Environ. Toxicol. Chem. 14(6):
1001-1009. doi:10.1002/etc.5620140611.

ECOTOX 8977: Shim, J.C., and L.S. Self (1973). Toxicity of Agricultural Chemicals to
Larvivorous Fish in Korean Rice Fields. Trop. Med. 15(3): 123-130.

MRID 05009242; Sanders, H.O. 1969. Toxicity of Pesticides to the Crustacean Gammarus
lacustris. Tech.Pap.No.25, U.S.D.I., Bur. Sports Fish. Wildl., Fish Wildl. Serv., Washington, DC,
18 p.

MRID 40098001: Mayer, F.L. and M.R. Ellersieck. 1986. Manual of acute toxicity:

Interpretation and data base for 410 chemicals and 66 species of freshwater animals. Resour.
Publ. No. 160, U.S. Dep. Interior, Fish Wildl. Serv., Washington, DC. 505 p.

MRID 41029701: Burgess, D. 1989. Acute flow-through toxicity of Cythion 57% EC to Daphnia
magna: Report No. 37394. Unpublished study prepared by Analytical Bio-Chemistry Labs Inc.
197 p.

MRID 48078003: Anonymous. 1968. Malathion Technical Toxicity to Rainbow Trout; Test
Number 105. Project Number: MB/69. Unpublished study prepared by Animal Biology
Laboratory. 13 p.

Bailey, H.C., and D.H.W. Liu. 1980. Lumbriculus variegatus, a Benthic Oligochaete, as a
Bioassay Organism. ASTM Spec. Tech. Publ., 205-215.

59


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Beaman, J.R., R. Finch, H. Gardner, F. Hoffmann, A. Rosencrance, and J.T. Zelikoff 1999.
Mammalian Immunoassays for Predicting the Toxicity of Malathion in a Laboratory Fish Model.
J. Toxicol. Environ. Health Part A 56(8): 523-542. doi:l0.1080/00984109909350175.

Bender, M.E., 1969a. The Toxicity of the Hydrolysis and Breakdown Products of Malathion to
Fathead minnow - University of Michigan.

Bender, M.E. 196b. Uptake and Retention of Malathion by the Carp. Prog. Fish-Cult. 31(3): 155-
159.

Bender, M.E., and J.R. Westman. 1976. The Toxicity of Malathion and Its Hydrolysis Products
to the Eastern Mudminnow, Umbra pygmaea (DeKay). Chesapeake Sci. 17(2): 125-128.

Beyers, D.W., T.J. Keefe and C.A. Carlson. 1994. Toxicity of carbaryl and malathion to two
federally endangered fishes, as estimated by regression and ANOVA. Environ. Toxicol. Chem.
13(1): 101-107.

Biesinger, K.E. 1973. The Chronic Toxicity of Some Pesticides to Daphnia magna. Interim Rep.
No. ROAP 16AAK, Task 06, Natl. Water Qual. Lab., Duluth, MN, 5 p.

Birge, W.J., J.A. Black, and D.M. Bruser 1979. Toxicity of Organic Chemicals to Embryo-
Larval Stages of Fish. EPA-560/11-79-007, U.S.EPA, Washington, D.C., 60 p.

Blakemore, G.; Burgess, D. 1990. Chronic Toxicity of Cythion to Daphnia magna Under Flow-
through Test Conditions: Lab Project Number: 37399. Unpublished study prepared by Analytical
BioChemistry Laboratories, Inc. 391 p.

Bowman, J. 1989. Acute Flow-Through Toxicity of Cythion Technical to Sheepshead Minnow
(Cyprinodon variegatus): Report No. 37397. Unpublished study prepared by Analytical Bio-
chemistry Laboratories, Inc. 205 p.

Burgess, D. 1989. Acute flow-through toxicity of Cythion 57% EC to Daphnia magna: Report
No. 37394. Unpublished study prepared by Analytical Bio-Chemistry Labs Inc. 197 p.

Cano, E., A. Jimenez, J.A. Cabral, and M.E. Ocete (1999). Acute Toxicity of Malathion and the
New Surfactant "Genapol OXD 080" on Species of Rice Basins. Bull. Environ. Contam. Toxicol.
63(1): 133-138. doi:10.1007/s001289900958.

Cohle, P. 1989. Early Life Stage Toxicity of Cythion to Rainbow Trout (Oncorhynchus mykiss)
in a Flow-through System: Lab Report Number: 37400. Unpublished study prepared by
Analytical Bio-Chemistry Laboratories, Inc. 1068 p.

Cope, O.B. 1965. Sport Fishery Investigations. Fish and Wildlife Service Circular 226, Effects of
Pesticides on Fish and Wildlife. Washington, DC, 51-63.

Cope, O.B. 1966. Contamination of the Freshwater Ecosystem by Pesticides. J. Appl. Ecol., 3,
33-44. doi: 10.2307/2401442.

Dortland, R.J. 1980. Toxicological Evaluation of Parathion and Azinphosmethyl in Freshwater
Model Ecosystems. Versl. Landbouwkd. Onderz., 898: 1-112.

60


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Dwyer, F.J., L.C. Sappington, D.R. Buckler and S.B. Jones. 1995. Use of surrogate species in
assessing contaminant risk to endangered and threatened fishes. EPA/600/R-96/029, U.S. EPA,
Washington, D.C.

Eaton, J.G. 1970. Chronic Malathion Toxicity to the Bluegill (Lepomis macrochirus Rafinesque).
Water Res. 4(10): 673-684.

Federle, P.F., and W.J. Collins. 1976. Insecticide Toxicity to Three Insects from Ohio Ponds.
Ohio J. Sci. 76(1): 19-24.

Foster, S., M. Thomas, and W. Korth. 1998. Laboratory-Derived Acute Toxicity of Selected
Pesticides to Ceriodaphnia dubia. Australas. J. Ecotoxicol. 4(1): 53-59.

Gaufin, A.R., L.D. Jensen, A.V. Nebeker, T. Nelson, and R.W. Teel. 1965. Toxicity of Ten
Organic Insecticides to Various Aquatic Invertebrates. Water Sewage Works, 12: 276-279.

Geiger, D.L., D.J. Call, and L.T. Brooke. 1988. Acute Toxicities of Organic Chemicals to
Fathead Minnows (Pimephales promelas) Volume IV. Center for Lake Superior Environmental
Studies, University of Wisconsin, Superior, WI, 4, 355 p.

Gries, T. and V. Purghart. 2001. Malathion Technical: Acute Toxicity Test with Bluegill Sunfish
(Lepomis macrochirus) Under Flow-Through Conditions: Final Report. Project Number:
314/FYF, 1005/018/105. Unpublished study prepared by Springborn Laboratories (Europe) Ag.
58 p.

Hansen and Parrish Hansen: D.J., and P.R. Parrish. 1977. Suitability of Sheepshead Minnows
(Cyprinodon variegatus) for Life-Cycle Toxicity Tests. ASTM Spec. Tech. Publ., 117-126.
(ECOTOX#:5074).

Hansen, C.R., Jr., and J. A. Kawatski 1976. Application of 24-Hour Postexposure Observation to
Acute Toxicity Studies with Invertebrates. J. Fish. Res. Board Can. 33(5): 1198-1201.
doi: 10.1139/f76-153.

Henderson, C., and Q.H. Pickering. 1958. Toxicity of Organic Phosphorus Insecticides to Fish.
Trans. Am. Fish. Soc. 87: 39-51.

Hermanutz, R.O. 1978. Endrin and Malathion Toxicity to Flagfish (Jordanella floridae). Arch.
Environ. Contam. Toxicol. 7(2): 159-168.

Hermanutz, R. O., Eaton, J. G., and Mueller, L. H. 1985. Toxicity of Endrin and Malathion
Mixtures to Flagfish (Jordanella floridae). Arch. Environ. Contam. Toxicol. 14: 307-314.

Hermens, J., H. Canton, N. Steyger, and R. Wegman. 1984. Joint Effects of a Mixture of 14
Chemicals on Mortality and Inhibition of Reproduction of Daphnia magna. Aquat. Toxicol. 5(4):
315-322.

Hoick, A.R., and C.L. Meek (1987). Dose-Mortality Responses of Crawfish and Mosquitoes to
Selected Pesticides. Am. Mosq. Control Assoc. J. 3(3): 407-411.

Johnson, C.R. 1980. The Effects of Five Organophosphorus Insecticides on Thermal Stress in
Tadpoles of the Pacific Tree Frog, Hyla regilla. Zool. J. Linn. Soc. 69(2): 143-147.

61


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Kaur, H., and H.S. Toor. 1995. Toxicity of Some Insecticides to the Fingerlings of Indian Major
Carp Cirrhina mrigala (Hamilton). Indian J. Ecol. 22(2): 140-142.

Keller, A.E., and D.S. Ruessler. 1997. The Toxicity of Malathion to Unionid Mussels:
Relationship to Expected Environmental Concentrations. Environ. Toxicol. Chem. 16(5): 1028-
1033. doi: 10.1002/etc.5620160524.

Key, P.B., and M.H. Fulton. 2006. Correlation Between 96-h Mortality and 24-h
Acetylcholinesterase Inhibition in Three Grass Shrimp Larval Life Stages. Ecotoxicol. Environ.
Saf. 63(3): 389-392.

Kikuchi, M., Y. Sasaki, and M. Wakabayashi. 2000. Screening of Organophosphate Insecticide
Pollution in Water by Using Daphnia magna. Ecotoxicol. Environ. Saf. 47(3): 239-245.
doi: 10.1006/eesa.2000.1958.

Kumar, K., and B.A. Ansari. 1984. Malathion Toxicity: Skeletal Deformities in Zebrafish
(Brachydanio rerio, Cyprinidae). Pestic. Sci., 15, 107-111.

Li, S.N., and D.F. Fan. 1996. Correlation Between Biochemical Parameters and Susceptibility of
Freshwater Fish to Malathion. J. Toxicol. Environ. Health 48(4): 413-418.

Liong, P.C., W.P. Hamzah, and V. Murugan. 1988. Toxicity of Some Pesticides Towards
Freshwater Fishes. Fish. Bull. Dep. Fish. (Malays.) No. 57, 13 p.

Lui, O. S., M. A. Ambak, and A. K. M. Mohsin. 1983. A Comparison of Tolerance Level of
Tilapia to Malathion on Clear and Muddy Bottom. Malays. Appl. Biol., 12, (2), 25-29.
(ECOTOX#: 11603).

Maas, J.L. 1982. Toxicity of Pesticides. Report No. 82, Laboratory for Ecotoxicology, Institute
for Inland Water Management and Waste Water Treatment, 15, 4 p.

Macek, K.J. and W.A. McAllister. 1970. Insecticide susceptibility of some common fish family
representatives. Trans. Am. Fish. Soc. 99(1): 20-27.

Macek, K.J., C. Hutchinson, and O.B. Cope. 1969. The Effects of Temperature on the
Susceptibility of Bluegills and Rainbow Trout to Selected Pesticides. Bull. Environ. Contam.
Toxicol. 4(3): 174-183.

Mayer, F.L. and M.R. Ellersieck. 1986. Manual of acute toxicity: Interpretation and database for
410 chemicals and 66 species of freshwater animals. Resour. Publ. No. 160, U.S. Dep. Interior,
Fish Wildl. Serv., Washington, DC. 505 p.

McKim, J.M., P.K. Schmieder, G.J. Niemi, R.W. Carlson, and T.R. Henry. 1987. Use of
Respiratory-Cardiovascular Responses of Rainbow Trout (Salmo gairdneri) in Identifying Acute
Toxicity Syndromes in Fish: Part 2. Malathion, Carbaryl, Acrolein and Benzaldehyde. Environ.
Toxicol. Chem. 6: 313-328.

Mount, D.I., and C.E. Stephan. 1967. A Method for Establishing Acceptable Toxicant Limits for
Fish - Malathion and the Butoxyethanol Ester of 2,4-D. Trans. Am. Fish. Soc. 96(2): 185-193.

62


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Olvera-Hernandez, E., L. Martinez-Tabche, and F. Martinez-Jeronimo. 2004. Bioavailability and
Effects of Malathion in Artificial Sediments on Simocephalus vetulus (Cladocera: Daphniidae).
Bull. Environ. Contam. Toxicol. 73(1): 197-204.

Palawski, D., J.B. Hunn, and F.J. Dwyer. 1985. Sensitivity of Young Striped Bass to Organic
and Inorganic Contaminants in Fresh and Saline Waters. Trans. Am. Fish. Soc. 114(5): 748-753.

Pandey, P.K., N.K. Singh, B.P. Choudhary, and G.K. Thakur (1981). Effect of
Organophosphorus Insecticide, Malathion, on the Haematology of Channa punctatus (Bloch). J.
Inl. Fish. Soc. India, 13(2): 120-121.

Pandey, S., R. Kumar, S. Sharma, N.S. Nagpure, S.K. Srivastava, and M.S. Verma (2005). Acute
Toxicity Bioassays of Mercuric Chloride and Malathion on Air-Breathing Fish Channa punctatus
(Bloch). Ecotoxicol. Environ. Saf. 61(1): 114-120.

Pickering, Q.H., C. Henderson, and A.E. Lemke 1962. The Toxicity of Organic Phosphorus
Insecticides to Different Species of Warmwater Fishes. Trans. Am. Fish. Soc. 91: 175-184.

Post, G. and T.R. Schroeder. 1971. The toxicity of four insecticides to four salmonid species.
Bull. Environ. Contam. Toxicol. 6(2): 144-155.

Ren, Z., J. Zha, M. Ma, Z. Wang, and A. Gerhardt. 2007. The Early Warning of Aquatic
Organophosphorus Pesticide Contamination by On-Line Monitoring Behavioral Changes of
Daphnia magna. Environ. Monit. Assess. 134(1-3): 373-383.

Sanders, H.O. 1969. Toxicity of Pesticides to the Crustacean Gammarus lacustris.
Tech.Pap.No.25, U.S.D.I., Bur. Sports Fish. Wildl., Fish Wildl. Serv., Washington, DC, 18 p.

Sanders, H.O. 1970. Pesticide Toxicities to Tadpoles of the Western Chorus Frog Pseudacris
triseriata and Fowler's Toad Bufo woodhousii fowleri. Copeia, 2: 246-251.

Sanders, H.O. 1972. Toxicity of Some Insecticides to Four Species of Malacostracan
Crustaceans. Tech. Pap. Bur. Sport Fish. Wildl., 66, 19 p.

Sanders, H.O., and O.B. Cope. 1966. Toxicities of Several Pesticides to Two Species of
Cladocerans. Trans. Am. Fish. Soc. 95(2): 165-169.

Schoettger, R.A. 1970. Fish-Pesticide Research Laboratory. In: Prog, in Sport Fish. Res., U.S.
Dep. Interior, Bur. Sport Fish, and Wildl. Res., Publ. No. 106, 2-40.

Snawder, J.E., and J.E. Chambers. 1989. Toxic and Developmental Effects of Organophosphorus
Insecticides in Embryos of the South African Clawed Frog. J. Environ. Sci. Health Part B Pestic.
Food Contam. Agric. Wastes 24(3): 205-218.

Sparling, D.W., and G. Fellers. 2007. Comparative Toxicity of Chlorpyrifos, Diazinon,
Malathion and Their Oxon Derivatives to Larval Rana boylii. Environ. Pollut. 147(3): 535-539.

Stephan, C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. 1985.
Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic
Organisms and their Uses. PB85-227049. Office of Research and Development. Duluth, MN,
Narragansett, RI, Corvallis, OR.

63


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Sulaiman, A.H., A.R. Abdullah, and S.K. Ahmad. 1989. Toxicity of Malathion to Red Tilapia
(Hybrid Tilapia mossambica x Tilapia nilotica): Behavioural, Histopathological and Anti-
cholinesterase Studies. Malays. Appl. Biol. 18(2): 163-170.

Sweilum, M.A. 2006. Effect of Sublethal Toxicity of some Pesticides on Growth Parameters,
Haematological Properties and Total Production of Nile Tilapia (Oreochromis niloticus L.) and
Water Quality of Ponds. Aquae. Res. 37(11): 1079-1089.

Ton, C., Y. Lin, and C. Willett 2006. Zebrafish as a Model for Developmental Neurotoxicity
Testing. Birth Defects Res. A Clin. Mol. Teratol. 76(7): 553-567.

U.S. EPA. 1976. Quality criteria for water. PB-263 943. Office of Water and Hazardous
Materials. Washington D.C. July 26, 1976.

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,

C.E.,	D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2005. Use of acute-to-chronic ratios in support of ecological risk assessment of
pesticides. Memo to Steve Bradbury, Director, Environmental Fate and Effects Division. Office
of Prevention, Pesticides, and Toxic Substances. June 7, 2005.

U.S. EPA. 2007. Risks of malathion use to the federally-listed California red legged frog (Rana
aurora draytonii). Pesticide effects determination. Office of Pesticide Programs. Washington,

D.C.	20460. October 19, 2007.

U.S. EPA. 2010. Risks of malathion use to the federally threatened delta smelt (Hypomesus
transpacificus) and California tiger salamander (Ambystoma californiense), Central California
distinct population segment, and the federally endangered California tiger salamander, Santa
Barbara County and Sonoma County distinct population segments. Environmental Fate and
Effects Division, OPP. Washington, D.C. 20460. September 29, 2010.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

Vedamanikam, V.J. 2009. Formation of Resistance in the Chironomus plumosus to Four
Pesticides over 45 Generations. Toxicol. Environ. Chem. 91(1): 187-194.

Whitten, B.K., and C.J. Goodnight. 1966. Toxicity of Some Common Insecticides to Tubificids.
J. Water Pollut. Control Fed. 38(2): 227-235.

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1.1.5 Comparison of Aquatic Life Toxicity Values for Diazinon: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
(CWA) (U.S. EPA 2024) for diazinon were obtained from the 2005 diazinon aquatic life criteria
(ALC) document (U.S. EPA 2005a), which serves as the based dataset, supplemented with an
update to this data from EPA ECOTOX Knowledgebase in 2010.

1.1.5.1 Diazinon Acute Toxicity Data

Acute data for diazinon were obtained from the 2005 diazinon aquatic life criteria (ALC)
document (U.S. EPA 2005a), which serves as the based dataset, supplemented with an update to
this data from ECOTOX in 2010. (See Table 1.) The ECOTOX 2010 update included additional
LCsos for Ceriodaphnia dubia, and one LC50 (and SMAV) for Chironomus riparius not in the
ALC document. The OPP pesticide effects determination document that served as the basis for
the invertebrate OPP benchmark concentration was also examined (U.S. EPA 2007). The
invertebrate (Ceriodaphnia dubia) and fish (Oncorhynchus my kiss) tests that served as the basis
for the OPP acute benchmarks were both included in the ALC document and/or the 2010
ECOTOX update.

The final diazinon acute dataset consisted of 27 SMAVs and 21 GMAVs, of which 14 SMAVs
and 11 GMAVs were for invertebrate taxa. Ranked species and genus mean acute values for all
invertebrates included in this analysis are listed in Table 2 below.

Table 1. Acute toxicity data of diazinon to freshwater aquatic organisms.

()\\



I.C50/

SMAV

(M8/U

<;may

(MS/'-)



MIJR

(lioup1

Species

l-X 50
(.uji/U

Reference

H

Planaria,

Dugesia tigrina

11,640

11,640

11,640

Phipps 1988

H

Ogliochate,

Lumbriculus variegates

9,980

-



Phipps 1988

H

Ogliochate (adult),

Lumbriculus variegates

9,700

-



Brooke 1989

H

Ogliochate,

Lumbriculus variegates

6,160

8,417

8,417

Ankley and Collyard 1995

G

Snail (2.4 g),

Gillia altilis

11,000

11,000

11,000

Robertson and Mazzella 1989

G

Apple snail (1 d),

Pomacea paludosa

2,950

-



Call 1993

G

Apple snail (7 d),

Pomacea paludosa

3,270

-



Call 1993

G

Apple snail (7 d),

Pomacea paludosa

3,390

3,198

3,198

Call 1993

D

Cladoceran (<24 hr),
Ceriodaphnia dubia

0.57





Norberg-King 1987

D

Cladoceran (<24 hr),
Ceriodaphnia dubia

0.66





Norberg-King 1987

D

Cladoceran (<24 hr),
Ceriodaphnia dubia

0.57





Norberg-King 1987

65


-------
()\\



I.C50 /

S\1 AY

(MS/'-)

<;may

(MS/'-)



MIJR

(iroup'

Species

IX 50
(Mli/U

Reference

D

Cladoceran (<24 hr),
Ceriodaphnia dubia

1





Norberg-King 1987

D

Cladoceran (<24 hr),
Ceriodaphnia dubia

0.6





Norberg-King 1987

D

Cladoceran (<6 hr),

Ceriodaphnia dubia

0.66





Norberg-King 1987

D

Cladoceran (<48 hr),
Ceriodaphnia dubia

0.35

-



Norberg-King 1987

D

Cladoceran (<48 hr),
Ceriodaphnia dubia

0.35

-



Norberg-King 1987

D

Cladoceran (<6 hr),

Ceriodaphnia dubia

0.25

-



Norberg-King 1987

D

Cladoceran (<24 hr),
Ceriodaphnia dubia

0.33

-



Norberg-King 1987

D

Cladoceran (<48 hr),
Ceriodaphnia dubia

0.35

-



Norberg-King 1987

D

Cladoceran (<48 hr),
Ceriodaphnia dubia

0.59

-



Norberg-King 1987

D

Cladoceran (<48 hr),
Ceriodaphnia dubia

0.43

-



Norberg-King 1987

D

Cladoceran (<48 hr),
Ceriodaphnia dubia

0.35

-



Norberg-King 1987

D

Cladoceran (<48 hr),
Ceriodaphnia dubia

0.36

-



Norberg-King 1987

D

Cladoceran (<48 hr),
Ceriodaphnia dubia

0.5

-



Ankley et al. 1991

D

Cladoceran (<24 hr),
Ceriodaphnia dubia

0.58

-



Bailey et al. 1997

D

Cladoceran (<24 hr),
Ceriodaphnia dubia

0.48

-



Bailey et al. 1997

D

Cladoceran (<24 hr),
Ceriodaphnia dubia

0.26

-



Bailey et al. 1997

D

Cladoceran (<24 hr),
Ceriodaphnia dubia

0.29

-



Bailey et al. 1997

D

Cladoceran (<24 hr),
Ceriodaphnia dubia

0.38

-



Bailey et al. 2001

D

Cladoceran (<24 hr),
Ceriodaphnia dubia

0.33

-



Bailey et al. 2001

D

Cladoceran (<24 hr),
Ceriodaphnia dubia

0.45

-



Banks et al. 2003

D

Cladoceran (<24 hr),
Ceriodaphnia dubia

0.21

0.4248

0.4248

Banks et al. 2005

D

Cladoceran (<20 hr),
Daphnia magna

0.96

-



Vilkas 1976

D

Cladoceran (<24 hr),
Daphnia magna

1.5

-



Dortland 1980

D

Cladoceran (<48 hr),
Daphnia magna

0.8

1.048



Ankley et al. 1991

D

Cladoceran (1st instar),

Daphnia pulex

0.90

-



Cope 1965a; Sanders and Cope
1966

66


-------
()\\
MIJR

(iroup'

Species

I.C50/
IX 50
(Mli/U

S\1 AY

(MS/'-)

<;may

(MS/'-)

Reference

D

Cladoceran (1st instar),

Daphnia pulex

0.8

-



Johnson and Finley 1980;
Mayer and Ellersieck 1986

D

Cladoceran (<48 hr),
Daphnia pulex

0.65

0.7764

0.9022

Ankley et al. 1991

D

Cladoceran (1st instar),

Simocephalus serrulatus

1.8

-



Cope 1965a; Sanders and Cope
1966; Mayer and Ellersieck
1986

D

Cladoceran (1st instar),

Simocephalus serrulatus

1.4

1.587

1.587

Sanders and Cope 1966;
Johnson and Finley 1980;
Mayer and Ellersieck 1986

E

Amphipod (mature),

Gammarus fasciatus

2.04

2.04



Johnson and Finley 1980;
Mayer and Ellersieck 1986

E

Amphipod (mature),

Gammarus pseudolimnaeus

16.82

16.82

5.858

Hall and Anderson 2004

E

Amphipod (7-14 d),

Hyalella azteca

6.51

6.51

6.510

Ankley and Collyard 1995

F

Stonefly

(larva, 30-35 mm),
Pteronarcys californica

25

25

25.000

Cope 1965a; Sanders and Cope
1968; Johnson and Finley 1980;
Mayer and Ellersieck 1986

F

Midge (2nd-3rd instar),

Chironomus riparius

450

450



Brooke 1989

F

Midge (3rd instar),

Chironomus tentans

10.7

10.7

69.39

Ankley and Collyard 1995

A

Cutthroat trout (2.0 g),

Oncorhynchus clarki

1,700

-



Johnson and Finley 1980;
Mayer and Ellersieck 1986

A

Cutthroat trout (2.0 g),

Oncorhynchus clarki

2,760

2,166



Mayer and Ellersieck 1986

A

Rainbow trout (3.7 cm),
Oncorhynchus mykiss

400

-



Beliles 1965

A

Rainbow trout (1.20 g),

Oncorhynchus mykiss

90

-



Cope 1965a; Johnson and
Finley 1980; Mayer and
Ellersieck 1986

A

Rainbow trout (25-50 g),

Oncorhynchus mykiss

3,200

-



Bathe et al. 1975a

A

Rainbow trout,

Oncorhynchus mykiss

90

-



Ciba-Giegy 1976

A

Rainbow trout,

Oncorhynchus mykiss

1,350

425.8



Meier et al. 1979; Dennis et al.
1980

A

Chinook salmon (alevin),

Oncorhynchus tshawytscha

29,500

29,500

3,008

Pincetich 2004; Viant et al.
2006

A

Brook trout (1 yr),
Salvelinus fontinalis

800

-



Allison and Hermanutz 1977

A

Brook trout (1 yr),
Salvelinus fontinalis

450

-



Allison and Hermanutz 1977

A

Brook trout (1 yr),
Salvelinus fontinalis

1,050

723.0



Allison and Hermanutz 1977

A

Lake trout (3.20 g),

Salvelinus namaycush

602

602

659.8

Johnson and Finley 1980;
Mayer and Ellersieck 1986

B

Splittail (larva, 6 wk),
Pogonichthys macrolepidotus

8,900

8,900

8,900

Teh et al. 2004

67


-------
()\\
MDR

(iroup'

Species

I.C50/
IX 50
(Mli/U

SMAV
(MU/U

<;may

(MS/'-)

Reference

B

Zebrafish (0.4 g),

Danio rerio

8,000

8,000

8,000

Keizeretal. 1991

B

Fathead minnow (juvenile),

Pimephales promelas

6,600

-



Allison and Hermanutz 1977

B

Fathead minnow (juvenile),

Pimephales promelas

6,800

-



Allison and Hermanutz 1977

B

Fathead minnow (juvenile),

Pimephales promelas

10,000

-



Allison and Hermanutz 1977

B

Fathead minnow
(newly hatched larva),

Pimephales promelas

6,900

-



Jarvinen and Tanner 1982

B

Fathead minnow (juvenile),

Pimephales promelas

9,350

7,804

7,804

University of Wisconsin-
Superior 1988

B

Goldfish (2.5-6.0 cm),

Carassius auratus

9,000

9,000

9,000

Beliles 1965

B

Flagfish (6 wk),
Jordanella floridae

1,500

-



Allison and Hermanutz 1977

B

Flagfish (7 wk),
Jordanella floridae

1,800

1,643

1,643

Allison and Hermanutz 1977

B

Guppy (0.6 g),

Poecilia reticulata

800

800

800

Keizeretal. 1991

B

Bluegill (1 yr),
Lepomis macrochirus

480

-



Allison and Hermanutz 1977

B

Bluegill (1 yr),
Lepomis macrochirus

440

459.6

460

Allison and Hermanutz 1977

B

Bluegill (0.8 g),

Lepomis macrochirus

120°

-



Meier et al. 1979; Dennis et al.
1980

B

Bluegill (1.00 g),

Lepomis macrochirus

168.0°





Johnson and Finley 1980;
Mayer and Ellersieck 1986

C

Green frog (stage 8),

Rana clamitans

50

50

50

Harris etal. 1998

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important

warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Acute Benchmark Values

The invertebrate OPP benchmark for diazinon is 0.105 |ig/L, which is V2 of the LC50 for the
cladoceran species C. dubia reported in a study by Banks et al. (2005). This test is the lowest of
24 LC50S that comprise the SMAV for C. dubia.

68


-------
The fish OPP benchmark for diazinon is 45 |ig/L, which is V2 of the LC50 of 90 |ig/L, the two
lowest LC50S for rainbow trout (Oncorhynchus mykiss), which is the second most sensitive fish
genera.

OW Acute Criterion

The acute criterion, or criterion maximum concentration (CMC) for diazinon in the 2005 ALC
document is 0.17 |ig/L.

Genus-Level Invertebrate-only HC05

The acute HC05 calculated from invertebrate genera shown in Table 2 above following the U.S.
EPA (1985) methodology is 0.1935 |ig/L (Table 3).

Table 2. Diazinon invertebrate SMAVs and GMAVs (^ig/L).

(Ionus

Species

S\1 AY

(IMAY

CMAY R;t 11k

Dugesia

tigrina

11,640

11,640

11

Gillia

altilis

11,000

11,000

10

Lumbriculus

variegatus

8,417

8,417

9

Pomacea

paludosa

3,198

3,198

8

Chironomus

riparius

450

69.39

7

Chironomus

tentans

10.7

Pteronarcys

californica

25

25

6

Hyalella

azteca

6.51

6.51

5

Gammarus

fasciatus

2.04

5.858

4

Gammarus

pseudolimnaeus

16.82

Simocephalus

serrulatus

1.587

1.587

3

Daphnia

pulex

0.7764

0.9022

2

Daphnia

magna

1.048

Ceriodaphnia

dubia

0.4248

0.4248

1

Table 3. HC05 calculated from the genus-level diazinon invertebrate-only data following the
U.S. EPA (1985) methodology.

N

Rank

(.MAY

ln(GMAV)

ln(GMAV)2

P=R/(N+1)

sqrt(P)

11

4

5.858

1.768

3.13

0.3333

0.5774



3

1.588

0.462

0.21

0.2500

0.5000



2

0.9022

-0.103

0.01

0.1667

0.4082



1

0.4248

-0.856

0.733

0.0833

0.2887



Sum:



1.27

4.08

0.8333

1.7743







S2 =

79.414

L =

-3.635

A =

-1.642

hc05 =

0.1935

69


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Table 4. Summary and comparison of acute values for diazinon.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

Pesticide

OPP

Invertebrate
ALB
(lowest LCso/2)
(Year published,
species)

OWALC (FAV/2)
(Year published, # of
genera, magnitude
relative to ALB)

OW Genus-level
Invertebrate-only
HCos/2
(# of genera, magnitude
relative to ALB)

Notes

Diazinon

0.105 ng/L
(2016; C. dubia)

0.170 ng/L
(2005, 20 genera,
0.61X)

0.097 (ig/L
(11 genera, 1.1X)

C. dubia is the most
sensitive species in the
invertebrate dataset and
FIFRA ALB is based on the
lowest of 24 LC50 values that
comprise the SMAV.

Figure 1 shows a genus-level sensitivity distribution for the diazinon dataset. Major taxonomic
groups are delineated by different symbols, and invertebrate genera are identified by name. Lines
denoting the CMC, invertebrate HCos/2, and OPP benchmark values are also included.

70


-------
100,000.00

10,000.00

1,000.00

W> 100.00

c
o
c

10.00

fO

1.00

0.10

•

Arthropod

o

Other Invertebrate

A

Mollusk

¦

Salmonid Fish

~

Other Fish

~

Amphibian

	

CMC



Genus-level Invertebrate



OPP Invert. Benchmark

	

OPP Fish Benchmark

	~-

(Pteronarcys

~

• Chironomus

Gammarus • • Hyalella

• Simocephalus
• Daphnia

Ceriodaphnia

Lumbriculus .

~ ~

~
Gilia

Dugesia

A



OPP Fish Benchmark = 45 ng/L

»FAV/2 = Criterion Maxmium Concentration = 0.17 pg/L
j^-OPP Invertebrate Benchmark = 0.105 [ig/L

0.01

•Genus-level Invertebrate HC05/2 = 0..0968 pg/L

0.0

0.1

0.2

0.3

0.4	0.5	0.6

Sensitivity Centile

0.7

0.8

0.9

1.0

Figure 1. Diazinon genus-level SD.

Symbols represent GMAVs calculated using all quantitative data from the aquatic life criteria document for diazinon (U.S. EPA
2005), additional data from a 2010 ECOTOX update, and the OPP benchmark document for diazinon (U.S. EPA 2007).

71


-------
1.1.5.2 Diazinon Chronic Toxicity Data

For chemicals lacking sufficient chronic data to satisfy the minimum taxonomic data
requirements, such as diazinon, OW calculates the final chronic value (FCV) as the final acute
value (FAV) divided by the final acute-to chronic ratio (FACR). OPP will also apply ACRs to
acute data for sensitive taxonomic groups to calculate chronic benchmarks when chronic test
data are not available. Calculations of ACRs following OPP and OW methodologies were
conducted, and the effects of these ACRs on the resulting OPP and OW chronic values were
compared.

Data Sources

The data sources for this analysis include data originally reported in the 2005 aquatic life criteria
(ALC) document (U.S. EPA 2005a), supplemented by additional test data from a 2010 ECOTOX
search update for diazinon, as well as additional data obtained from OPP-authored pesticide
effects determination (U.S. EPA 2007) and problem formulation (U.S. EPA 2008) reports.

ACR Calculations

ACR calculations following OW and OPP methodologies are described below. All available
chronic diazinon data are shown in Table 5. All available acute data for species that also have
chronic data are shown in Table 6. Table 7 lists all ACRs by species and calculation method.
ACRs could be calculated for two invertebrate and four fish species following the OW approach,
and for three invertebrate and four fish species following the OPP approach (U.S. EPA 2005b).

Invertebrate ACRs

Ceriodaphnia dubia

The ACR following the OW approach was 1.112, which was the geometric mean of ten acute
values from the same laboratory (nine reported in Norberg-King 1987 and one reported in
Ankley et al. 1991) divided by the MATC from a chronic test performed in the same laboratory
(Norberg-King 1987). The ACR following the OPP approach was 1.709, using the same acute
test data and the NOEC from the paired chronic test.

Daphnia magna

An ACR could not be calculated following the OW approach, because none of the acute tests
were performed in the same laboratory using the same dilution water as any of the chronic tests.
The ACR following the OPP approach was 5.190, which was the geometric mean of the three
acceptable acute values divided by the geometric mean of the two acceptable NOECs.

Americamysis bahia

The ACR following the OW approach was 1.586, which was acute value reported in Nimmo et
al. (1981) divided by the corresponding MATC for the paired chronic test. The ACR following
the OPP approach was 2.295, which was acute value reported in Nimmo et al. (1981) divided by
the corresponding NOEC for the paired chronic test

72


-------
Vertebrate (Fish) ACRs

Salvelinus fontinalis

The ACR following the OW approach was >903.8, which was the geometric mean of three
acceptable acute values reported in Allison and Hermanutz (1977) divided by the paired OW-
calculated NOEC of <0.8 |ig/L. The ACR following the OPP approach was >1,315, which was
the geometric mean of three acceptable acute values reported in Allison and Hermanutz (1977)
divided by the paired OPP-calculated NOEC of <0.55 |ig/L.

Pimephales promelas

In both the OW- and OPP-approaches, two ACRs were calculated using paired data from
Jarvinen and Tanner (1982) and University of Wisconsin-Superior (1988) - Norberg-King
(1989). The final P. promelas ACRs, calculated as the geometric mean of the two paired tests,
was 196.2 following the OW approach and 279.6 following the OPP approach.

Jordanella floridae

The ACR following the OW approach was 23.84, which was the geometric mean of two acute
values reported in Allison (1977) divided by the paired MATC. The ACR following the OPP
approach was 30.43, which was the geometric mean of two acute values reported in Allison
(1977) divided by the paired NOEC.

Cyprinodon variegatus

The ACR following the OW approach was >2,979, which was the Goodman et al. (1979), Mayer
(1987) acute value divided by the OW-calculated paired NOEC of <0.47 |ig/L. The ACR
following the OPP approach was 3,590, which was the Goodman et al. (1979) - Mayer (1987)
acute value divided by the OPP-calculated paired NOEC of 0.36 |ig/L.

Final ACRs

The final ACRs (FACRs) for the two approaches, expressed as the geometric mean of all
available ACRs, is 53.01 following the OW approach, and 50.33 following the OPP approach.
The OW-calculated FACR is larger the OPP FACR because the OPP FACR includes a relatively
small ACR of 5.190 for D. magna that could not be calculated following the OW approach.

When the comparison is limited to those ACRs both approaches have in common, the OPP
FACR is 73.49.

FACRs following both approaches are comprised of two to three relatively small ACRs for
acutely sensitive invertebrate taxa, and four much larger ACRs for acutely insensitive fish
species. The Guidelines (U.S. EPA 1985) specify that if the ACRs appear to increase or decrease
as the species mean acute values (SMAVs) increase, the FACR should be calculated as the
geometric mean for those species whose SMAVs are close to the final acute value (FAV). This is
the case for diazinon, and following the approach used in the 2005 ALC, the FACR is calculated
as the geometric mean of the acutely sensitive invertebrate species. When limited to invertebrate
species, the FACR following the OW approach is calculated as the geometric mean of the ACRs
for C. dubia (1.112) and A. bahia (1.586). Because the final chronic value cannot be larger than
the final acute value, the calculated ACR of 1.328 is rounded up to 2. The invertebrate-only

73


-------
FACR following the OPP approach is the geometric mean of the ACRs for C. dubia (1.709), D.
magna (5.190), and A bahia (2.295), or 2.731.

Comparison of Freshwater Chronic Values for Diazinon
OPP Chronic Benchmarks

For diazinon, the freshwater invertebrate chronic benchmark is 0.17 |ig/L, which is a NOEC
from a registrant submitted test for Daphnia magna (Table 27 in U.S. EPA 2007); and the
freshwater fish chronic benchmark is <0.55 |ig/L, which a NOEC from Allison and Hermanutz
(1977) for Salvelinusfontinalis based on reduced growth (Table 27 in U.S. EPA 2007).

OW Freshwater Chronic Values - All Taxa

Final chronic concentrations following the ACR methodology are calculated by dividing the final
acute value by an ACR. For diazinon, the only available FAV calculated from all taxa is the
FAV of 0.3397 |ag/L reported in the diazinon ALC (U.S. EPA 2005a). The final chronic value
following the OW-ACR approach is 0.1699 ng/L (0.3397 ng/L -h 2), and the final chronic value
following the OPP-ACR approach is 0.1244 ng/L (0.3397 |ag/L 2.731).

OW Freshwater Chronic Values - Invertebrate Taxa

Final chronic concentrations for the invertebrate-only diazinon dataset are calculated by dividing
the final invertebrate acute value by an ACR. This dataset was comprised of acute invertebrate
test data found in the 2005 ALC and the 2010 ECOTOX update. The 2007 and 2008 OPP
documents were also examined but these did not include additional acute invertebrate test data.
The resulting acute HCos calculated from the 11 invertebrate genera using the Guidelines SSD
was 0.1935 ng/L. The final invertebrate chronic value following the OW-ACR approach is
0.09675 |ag/L (0.1935 ng/L -h 2), and the final chronic value following the OPP-ACR approach is
0.07085 |ag/L (0.1935 |ag/L ^ 2.731). Table 8 lists all chronic values calculated following the
different approaches.

74


-------
Table 5. Chronic test data for diazinon.

All concentrations expressed as ng/L. Bolded rows are chronic test results reported by OPP that differ from results reported by OW.

Genus

Species

NOEC

LOEC

MATC

Reference

Test data reported in:

Notes

2005
ALC

2010
ECOTOX
Search

2007
OPP

2008
OPP

Invertebrates

Ceriodaphnia

dubia

0.22

0.52

0.338

Norberg-King 1987

Table 2

X









Daphnia

magna

0.24

0.64

0.392

Biesinger 1973



X







Daphnia

magna

0.17

<0.32

0.233

Surprenant 1988





Table
27

Table 3





Americamysis

bahia

2.1

4.4

3.040

Nimmo et al. 1981



X



Table 3



Vertebrates

Salvelinus

fontinalis

<0.8

0.8

-

Allison and
Hermanutz 1977

Table 2

X





OW calculated value

Salvelinus

fontinalis

<0.55

0.55

-

Allison and
Hermanutz 1977





Table
27

Table 3

OPP calculated value



Pimephales

promelas

50

90

67.08

Jarvinen and Tanner
1982

Table 2

X







Pimephales

promelas

16.5

38

24.97

Norberg-King 1989

Table 2

X





Paired with University of
Wisconsin-Superior 1988



Jordanella

floridae

54

88

68.93

Allison 1977

Table 2

X









Cyprinodon

variegatus

<0.47

0.47

-

Goodman etal. 1979

Table 2

X





OW calculated value

Cyprinodon

variegatus

0.39

0.56

0.47

Goodman et al.
1979







Table 3

OPP calculated value

75


-------
Table 6. Acute diazinon test data for species with chronic test data.

All concentrations expressed as ng/L.

(Ion us

Species

I X 50

or
IX 50

<>\Y-
ACR
Acute
\ :ilue

()l»l»-
ACR
Acute
Ysiliie

Re Terence

lest iliitii reported in:

Notes

2005
Alt

2010
IX ()T()\

200S
()l»l»



Invertebrates

Ceriodaphnia

dubia

0.35

0.3760

0.3760

Norberg-King 1987

Table 1

X



OW, OPP-ACR acute value

Ceriodaphnia

dubia

0.35





Norberg-King 1987

Table 1

X



OW, OPP -ACR acute value

Ceriodaphnia

dubia

0.25





Norberg-King 1987

Table 1

X



OW, OPP -ACR acute value

Ceriodaphnia

dubia

0.33





Norberg-King 1987

Table 1

X



OW, OPP -ACR acute value

Ceriodaphnia

dubia

0.35





Norberg-King 1987

Table 1

X



OW, OPP -ACR acute value

Ceriodaphnia

dubia

0.59





Norberg-King 1987

Table 1

X



OW, OPP -ACR acute value

Ceriodaphnia

dubia

0.43





Norberg-King 1987

Table 1

X



OW, OPP -ACR acute value

Ceriodaphnia

dubia

0.35





Norberg-King 1987

Table 1

X



OW, OPP -ACR acute value

Ceriodaphnia

dubia

0.36





Norberg-King 1987

Table 1

X



OW, OPP -ACR acute value

Ceriodaphnia

dubia

0.5





Ankley et al. 1991

Table 1

X



OW, OPP -ACR acute value

Ceriodaphnia

dubia

0.58





Bailey et al. 1997

Table 1

X





Ceriodaphnia

dubia

0.48





Bailey et al. 1997

Table 1

X





Ceriodaphnia

dubia

0.26





Bailey et al. 1997

Table 1

X





Ceriodaphnia

dubia

0.29





Bailey et al. 1997

Table 1

X





Ceriodaphnia

dubia

0.38





Bailey et al. 2001



X





Ceriodaphnia

dubia

0.33





Bailey et al. 2001



X





Ceriodaphnia

dubia

0.45





Banks et al. 2003



X





Ceriodaphnia

dubia

0.21





Banks et al. 2005



X

Table 3



Ceriodaphnia

dubia

0.57





Norberg-King 1987

Table 1

X



Not used to calculate SMAV

Ceriodaphnia

dubia

0.66





Norberg-King 1987

Table 1

X



Not used to calculate SMAV

Ceriodaphnia

dubia

0.57





Norberg-King 1987

Table 1

X



Not used to calculate SMAV

Ceriodaphnia

dubia

>1.0





Norberg-King 1987

Table 1

X



Not used to calculate SMAV

Ceriodaphnia

dubia

>0.6





Norberg-King 1987

Table 1

X



Not used to calculate SMAV

Ceriodaphnia

dubia

0.66





Norberg-King 1987

Table 1

X



Not used to calculate SMAV

Ceriodaphnia

dubia

0.57





Norberg-King 1987

Table 1

X



Not used to calculate SMAV

Ceriodaphnia

dubia

0.66





Norberg-King 1987

Table 1

X



Not used to calculate SMAV



Daphnia

magna

0.96

n/a

1.048

Vilkas 1976

Table 1

X



OPP-ACR acute value

Daphnia

magna

1.5





Dortland 1980

Table 1

X



OPP-ACR acute value

Daphnia

magna

0.8





Ankley et al. 1991

Table 1

X



OPP-ACR acute value



Americamysis

bahia

4.82

4.82

4.82

Nimmo et al. 1981

Table 1

X



OW, OPP-ACR acute value

76


-------
Genus

Species

EC50

or
LC50

ow-

ACR
Acute
Value

OPP-

ACR

Acute

Value

Reference

Test data reported in:

Notes

2005
ALC

2010
ECOTOX

2008
OPP



Americamysis

bahia

4.2





Suprenant 1988





Table 3



Americamysis

bahia

8.5





Thursby and Berry 1988

Table 1

X



Not used to calculate SMAV

Americamysis

bahia

8.5





Cripe 1994

Table 1

X



Not used to calculate SMAV

Vertebrates

Salvelinus

fontinalis

800

723.0

723.0

Allison and Hermanutz 1977

Table 1

X



OW, OPP-ACR acute value

Salvelinus

fontinalis

450





Allison and Hermanutz 1977

Table 1

X



OW, OPP-ACR acute value

Salvelinus

fontinalis

1,050





Allison and Hermanutz 1977

Table 1

X



OW, OPP-ACR acute value



Pimephales

promelas

6,900

6,900

6,900

Jarvinen and Tanner 1982

Table 1

X



OW, OPP-ACR acute value

Pimephales

promelas

9,350

9,350

9,350

University of Wisconsin-
Superior 1988

Table 1

X



OW, OPP-ACR acute value.
Paired with Norberg-King
1989

Pimephales

promelas

6,600





Allison and Hermanutz 1977

Table 1

X





Pimephales

promelas

6,800





Allison and Hermanutz 1977

Table 1

X





Pimephales

promelas

10,000





Allison and Hermanutz 1977

Table 1

X





Pimephales

promelas

4,300





Jarvinen and Tanner 1982

Table 1

X



Not used to calculate SMAV

Pimephales

promelas

2,100





Jarvinen and Tanner 1982

Table 1

X



Not used to calculate SMAV

Pimephales

promelas

10,300





Meier et al. 1979; Dennis et al.
1980

Table 1

X



Not used to calculate SMAV



Jordanella

floridae

1,500

1,643

1,643

Allison 1977

Table 1

X



OW-ACR acute value

Jordanella

floridae

1,800





Allison 1977

Table 1

X



OW-ACR acute value



Cyprinodon

variegatus

1,400

1,400

1,400

Goodman et al. 1979; Mayer
1987

Table 1

X



OW-ACR acute value

77


-------
Table 7. ACI

ts by species and calculation method.

Genus

Species

ACR

Notes

OW-

ACR

OPP-

ACR

Invertebrates

Ceriodaphnia

dubia

1.112

1.709



Daphnia

magna

N/A

5.190



Americamvsis

bahia

1.586

2.295



Vertebrates

Salvelimis

fontinalis

>903.8

>1,315



Pimephales

promelas

196.2

279.6

Value in parentheses used lowest acute flow-through test.
Used in final "All Taxa" calculation.

Jordanella

floridae

23.84

30.43



Cvprinodon

variegatus

>2,979

3,590













All Taxa

53.01

50.33



All Invertebrates (FACR)

1.328

2.731

OW-FACR rounded up to 2.

Table 8. Summary and comparison freshwater chronic values for diazinon.

Magnitude relative to ALB is the OPP ALB/OW value; a ratio < 1 means the OPP ALB value is
lower than the OW value, a ratio >1 means the OPP ALB is higher than the OW value. Note: For
GLI Tier II values, a default ACR of 18 is used when empirically derived ACRs are not
available.

Pesticide

Most Sensitive OPP ALB
(Year published, species)

OWALC
(# of ACRs filled, magnitude
relative to ALB)

OW Invertebrate-only HCos
(# of ACRs filled, magnitude
relative to ALB)

Diazinon

0.17 ng/L

(2016, Daphnia magna)

0.17 ng/L
(ALC, IX)

0.097 (ig/L

(See Table 7 for ACRs, 1.8X)

1.1.5.3 Diazinon References

Allison, D.T. 1977. Use of Exposure Units for Estimating Aquatic Toxicity of Organophosphate
Pesticides. EPA-600/3-77-077, U.S.EPA, Duluth, MN, 25 p. ECOREF#:9931.

Allison, D.T. and R.O. Hermanutz. 1977. Toxicity of diazinon to brook trout and fathead
minnows. PB-269 293 or EPA-600/3-77-060. National Technical Information Service,
Springfield, VA.

Ankley, G.T. and S.A. Collyard. 1995. Influence of piperonyl butoxide on the toxicity of
organophosphate insecticides to three species of freshwater benthic invertebrates. Comp.
Biochem. Physiol. 11OC: 149-155.

Ankley, G.T., J.R. Dierkes, D.A. Jensen and G.S. Peterson. 1991. Piperonyl butoxide as a tool in
aquatic toxicological research with organophosphate insecticides. Ecotoxicol. Environ. Safety
21:266-274.

Bailey, H.C., J.L. Miller, M.J. Miller, L.C. Wiborg, L. Deanovic and T. Shed. 1997. Joint acute
toxicity of diazinon and chlorpyrifos to Ceriodaphnia dubia. Environ. Toxicol. Chem. 16:2304-
2308.

78


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Bailey, H.C., J.R. Elphick, R. Krassoi and A. Lovell, A. 2001. Joint acute toxicity of diazinon
and ammonia to Ceriodaphnia dubia. Environ. Toxicol. Chem. 20(12): 2877-2882.

Banks, K.E., S.H. Wood, C. Matthews and K.A. Thuesen. 2003. Joint acute toxicity of diazinon
and copper to Ceriodaphnia dubia. Environ. Toxicol. Chem. 22: 1562-1567.

Banks, K.E., D.H. Hunter and D.J. Wachal. 2005. Diazinon in surface waters before and after a
federally-mandated ban. Sci. Total Environ. 350: 86-93.

Banks, K.E., P.K. Turner, S.H. Wood and C. Matthews. 2005. Increased toxicity to Ceriodaphnia
dubia in mixtures of atrazine and diazinon at environmentally realistic concentrations.

Ecotoxicol. Environ. Safety 60(1): 28-36.

Bathe, R., K. Sachsse, L. Ullmann, W.D. Hormann, F. Zak and R. Hess. 1975a. The evaluation
of fish toxicity in the laboratory. Proc. Eur. Soc. Toxicol. 16:113-124.

Beliles, R. 1965. Diazinon safety evaluation on fish and wildlife: Bobwhite quail, goldfish,
sunfish and rainbow trout. U.S. Environmental Protection Agency, Office of Pesticide Programs
registration standard.

Biesinger, K.E. 1973. The Chronic Toxicity of Some Pesticides to Daphnia magna. Interim Rep.
No. ROAP 16AAK, Task 06, Natl. Water Qual. Lab., Duluth, MN, 5 p. ECOREF#: 117172.

Brooke, L. 1989. Results of Freshwater Exposures with the Chemicals 2,4-D and Diazinon to the
Larval Leopard Frog (Rana pipiens), Juvenile Fathead Minnows (Pimephales promelas), Larval
Midge (Chironomus riparius) and Adult Oligochaete W. February 15th Memo to R.Spehar,
U.S.EPA, Duluth, MN, 6 p.

Call, D.J. 1993. Validation study of a protocol for testing the acute toxicity of pesticides to
invertebrates using the apple snail (Pomacea paludosa). Final Report to U.S. EPA Cooperative
Agreement, No. CR 819612-01.

Ciba-Geigy Corporation. 1976. Reports of investigations made with respect to fish and wildlife
requirements for diazinon and its formualted products. U.S. Environmental Protection Agency,
Office of Pesticide Programs registration standard.

Cope, O.B. 1965a. Contamination of the freshwater ecosystem by pesticides. J. Appl. Ecol.
3 ( Suppl ement): 3 3 -44.

Cripe, G.M. 1994. Comparative Acute Toxicities of Several Pesticides and Metals to Mysidopsis
bahia and Postlarval Penaeus duorarum. Environ. Toxicol. Chem. 13(11): 1867-1872.
doi:10.1002/etc.5620131119. ECOREF#: 13513.

Dennis, W.H., A.B. Rosencrance, W.F. Randall and E.P. Meier. 1980. Acid hydrolysis of
military standard formulations of diazinon. J. Environ. Sci. Health B15:47-60.

Dortland, R.J. 1980. Toxicological evaluation of parathion and azinphosmethyl in freshwater
model ecosystems. Agric. Res. Rep. (Versl. landbouwk. Onderz.) 898:1-112.

Goodman, L.R., D.J. Hansen, D.L. Coppage, J.C. Moore, and E. Matthews. 1979. Diazinon:
Chronic Toxicity to, and Brain Acetylcholinesterase Inhibition in, the Sheepshead Minnow,
Cyprinodon variegatus. Trans. Am. Fish. Soc., 108(5): 479-488. ECOREF#:5604.

79


-------
Hall, L.W. and R.D. Anderson. 2004. Acute Toxicity of Diazinon to the Amphipod, Gammarus
pseudolimnaeus. (Data Report, April 8). University of Maryland, Agricultural Experiment
Station, Queenstown, MD.

Harris, M.L., C.A. Bishop, J. Struger, B. Ripley and J.P. Bogart. 1998. The functional integrity
of northern leopard frog (Rana pipiens) and green frog (Rana clamitans) populations in orchard
wetlands. II. Effects of pesticides and eutrophic conditions on early life stage development.
Environ. Toxicol. Chem. 17:1351-1363.

Jarvinen, A.W. and D.K. Tanner. 1982. Toxicity of selected controlled release and corresponding
unformulated technical grade pesticides to the fathead minnow Pimephales promelas. Environ.
Pollut. (Series A) 27:179-195.

Johnson, W.W. and M.T. Finley. 1980. Handbook of acute toxicity of chemicals to fish and
aquatic invertebrates. Resource Publication 137. U.S. Fish and Wildlife Service, U.S.

Department of Interior, Washington, DC.

Keizer, J., G. D'Agostino and L. Vittozzi. 1991. The importance of biotransformation in the
toxicity of xenobiotics to fish. I. Toxicity and bioaccumulation of diazinon in guppy (Poecilia
reticulata) and zebra fish (Brachydanio rerio). Aquat. Toxicol. 21:239-254.

Mayer, F.L., Jr. 1987. Acute toxicity handbook of chemicals to estuarine organisms. EPA/600/8-
87/017. 274 pp.

Mayer, F.L., Jr. and M.R. Ellersieck. 1986. Manual of acute toxicity: interpretation and data base
for 410 chemicals and 66 species of freshwater animals. Resource Publication No. 160, Fish and
Wildlife Service, U.S. Department of Interior, Washington, DC. 505 p.

Meier, E.P., W.H. Dennis, A.B. Rosencrance, W.F. Randall, W.J. Cooper and M.C. Warner.
1979. Sulfotepp, atoxic impurity in formulations of diazinon. Bull. Environ. Contam. Toxicol.
23:158-164.

Nimmo, D.R., T.L. Hamaker, E. Matthews, and J.C. Moore. 1981. An Overview of the Acute
and Chronic Effects of First and Second Generation Pesticides on an Estuarine Mysid. In: F.J.
Vernberg, A. Calabrese, F.P. Thurberg, and W.B. Vernberg (Eds.), Biological Monitoring of
Marine Pollutants, Academic Press, Inc., NY, 3-19. ECOREF#:4891.

Norberg-King, T.J. 1987. Toxicity Data on Diazinon, Aniline, 2,4-Dimethylphenol. U.S.EPA,
Duluth, MN:11 p. (Memorandum to C.Stephan, U.S.EPA, Duluth, MN; D.Call and L.Brooke,
Center for Lake Superior Environmental Studies, Superior, WI, August 31).

Norberg-King, T.J. 1989. An Evaluation of the Fathead Minnow Seven-Day Subchronic Test for
Estimating Chronic Toxicity. Environ. Toxicol. Chem. 8(11): 1075-1089. ECOREF#:5313.

Phipps, G.L. 1988. Diazinon acute tests for criteria development. (Memorandum to R. Spehar,
U.S. EPA, Duluth, MN. April 29).

Pincetich, C.A. 2004. Metabolic Effects of Pesticide Exposure During Embryogenesis in Medaka
(Oryzias latipes) and Chinook Salmon (Oncorhynchus tshawytscha). Ph.D. Thesis, University of
California, Davis, 139 p.

80


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Robertson, J.B. and C. Mazzella. 1989. Acute toxicity of the pesticide diazinon to the freshwater
snail Gillia altilis. Bull. Environ. Contam. Toxicol. 42:320-324.

Sanders, H.O. and O.B. Cope. 1968. The relative toxicities of several pesticides to naiads of
three species of stoneflies. Limnol. Oceanogr. 13:112-117.

Stephan, C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. 1985.
Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic
Organisms and their Uses. PB85-227049. Office of Research and Development. Duluth, MN,
Narragansett, RI, Corvallis, OR.

Surprenant, D. C. 1988. The Chronic Toxicity of 14C-Diazinon to Daphnia magna Under Flow-
Through Conditions. Report No. 88-4-2644. Conducted by Springborn Life Sciences, Inc.,
Wareham, MA. Submitted by CIBA-GEIGY Corporation, Greensboro, NC. EPA Accession
[MRID] No. 407823-02.

Teh, S.J., G.H. Zhang, T. Kimball and F.C. Teh. 2004. Lethal and sublethal effects of
esfenvalerate and diazinon on splittail larvae. American Fisheries Society Symposium. 2004.
243-253.

Thursby, G.B., and W.J. Berry. 1988. Acute Toxicity of Diazinon to Saltwater Animals. Letter to
J. Scott and D.J. Hansen, Univ. of Rhode Island, Kingston, RI, 10 p. ECOREF#:73146.

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2005a. Aquatic life ambient water quality criteria for diazinon. Office of Water. EPA-
822-R-05-006. December 2005.

U.S. EPA. 2005b. Use of acute-to-chronic ratios in support of ecological risk assessment of
pesticides. Memo to Steve Bradbury, Director, Environmental Fate and Effects Division. Office
of Prevention, Pesticides, and Toxic Substances. June 7, 2005.

U.S. EPA. 2007. Risks of diazinon use to the federally listed California red legged frog (Rana
aurora draytonii). Pesticide effects determination. Office of Pesticide Programs. Washington,
D C. 20460. July 20, 2007.

U.S. EPA. 2008. Problem formulation for the environmental fate and ecological risk, endangered
species and drinking water assessments in support of the registration review of diazinon. Office
of Pesticide Programs. Washington, D.C. 20460. March 26, 2008.

U.S. EPA. 2017. Aquatic life benchmarks for pesticide registration. Accessed July 11, 2017.
https://www.epa.gov/pesticide-science-and-assessing-pesticide-risks/aquatic-life-benchmarks-

pesti ci de-regi strati on.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

81


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University of Wisconsin-Superior. 1988. Acute toxicities of organic chemicals to fathead
minnows (Pimephales promelas). Vol. 4. Geiger, D.L., D.J. Call and L.T. Brooke (Eds.). Center
for Lake Superior Environmental Studies, University of Wisconsin-Superior Press, Superior, WI.
355 p.

Viant, M.R., C.A. Pincetich, and R.S. Tjeerdema 2006. Metabolic Effects of Dinoseb, Diazinon
and Esfenvalerate in Eyed Eggs and Alevins of Chinook Salmon (Oncorhynchus tshawytscha)
Determined by 1H NMR Metabolomics. Aquat. Toxicol. 77(4): 359-371.

Vilkas, A. 1976. Acute toxicity of diazinon technical to the water flea, Daphnia magna Straus.
U.S. Environmental Protection Agency, Office of Pesticide Programs registration standard.

82


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1.1.6 Comparison of Aquatic Life Toxicity Values for Chlorpyrifos: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
(CWA) (U.S. EPA 2024) for chlorpyrifos were obtained from the 1986 OW criteria, which serves
as the base dataset, supplemented with an update to this data from the EPA's ECOTOX
Knowledgebase in 2010, and with additional data reported in the OPP's chlorpyrifos re-
registration eligibility assessment document U.S. EPA (2000). There was no comparative
analysis for chlorpyrifos chronic data.

1.1.6.1 Chlorpyrifos Acute Toxicity Data

Acceptable acute data for chlorpyrifos were obtained from the 1986 criteria, which serves as the
base dataset, supplemented with an update to this data from ECOTOX in 2010, and with
additional LCsos reported in the chlorpyrifos re-registration eligibility assessment document U.S.
EPA (2000). (See Table 1.) Four acute tests were included in U.S. EPA (2000) that were not in
the 2010 ECOTOX update: two LCsos (0.1 |ig/L, 1.7 |ig/L) for Daphnia magna, including the
value upon which the OPP invertebrate benchmark is based; an LCso of 8.2 |ig/L for the stonefly
species Classenia sabulosa, and an LCso of 150 |ig/L for Pimephalespromelas. The C. sabulosa
LCso of 8.2 |ig/L was considered for inclusion but ultimately not included. This was a the 24-hr
LC50 from a test reported in Mayer and Ellersieck (1986) that also reported a 96-hr LC50 of 0.57
|ig/L. The 96-hr LC50 was included in the 2010 ECOTOX update, but not the 24-hr LC50, due to
the shorter exposure duration. Because the 96-hr result from this test was already represented, the
24-hr LC50 of 8.2 |ig/L was not used in this evaluation.

The final dataset consisted of 94 acceptable LCsos for 32 SMAVs and 28 GMAVs, of which 18
SMAVs and 15 GMAVs were for invertebrates. Ranked invertebrate GMAVs are listed in Table
2.

83


-------
Table 1. Acute toxicity data of chlorpyrifos to freshwater aquatic organisms

()\\





I X 50/

S\1 AY

(MS/'-)

(IMAY

(MS/'-)



MIJR

(ironp'1

(ionus

Species

I X 50

(MU/I-)

Reference

G

Amblema

phcata

1,200

1,200

1,200

Doranetal. 2001

G

Lampsilis

siliquoidea

250

250

250

Bringolf et al. 2007

G

Aplexa

hypnorum

806

806

806

Phipps and Holcombe 1985a; b

D

Ceriodaphnia

dubia

0.06





Bailey et al. 1996

D

Ceriodaphnia

dubia

0.06





Bailey et al. 1996

D

Ceriodaphnia

dubia

0.053





Bailey et al. 1997

D

Ceriodaphnia

dubia

0.055





Bailey et al. 1997

D

Ceriodaphnia

dubia

0.058





Bailey et al. 1997

D

Ceriodaphnia

dubia

0.078





Bailey et al. 1997

D

Ceriodaphnia

dubia

0.058

0.0627

0.0627

Bailey et al. 1997

D

Ceriodaphnia

dubia

0.064

Bailey et al. 1997

D

Ceriodaphnia

dubia

0.066





Bailey et al. 1997

D

Ceriodaphnia

dubia

0.079





Bailey et al. 1997

D

Ceriodaphnia

dubia

0.08





Foster etal. 1998

D

Ceriodaphnia

dubia

0.056





Harmon et al. 2003

D

Ceriodaphnia

dubia

0.050





El-Merhib et al. 2004

D

Ceriodaphnia

dubia

0.07





Pablo et al. 2008

D

Daphnia

ambigua

0.035

0.035



Harmon et al. 2003

D

Daphnia

magna

1.0





Kersting and Van Wijngaarden 1992

D

Daphnia

magna

0.325





Diamantino et al. 1998

D

Daphnia

magna

0.344





Diamantino et al. 1998

D

Daphnia

magna

0.19

0.4811

0.1298

Kikuchi et al. 2000

D

Daphnia

magna

1.074



Gaizick et al. 2001

D

Daphnia

magna

0.74





Palma et al. 2008

D

Daphnia

magna

0.10





MRID 40840902; Burgess 1988

D

Daphnia

magna

1.7





MRID 00102520; McCarthy 1977

D

Simocephalus

vetulus

0.09

0.09

0.09

Pablo et al. 2008

84


-------
()\\
MIJR

(iroup'1

(ionus

Species

I X 50/
I X 50
(MB/I.)

S\1 AY

(M8/U

(IMAY

(MS/'-)

Reference

F

Peltodytes

sp.

0.8

0.8

0.8

Federle and Collins 1976

F

Chironomus

plumosus

1.3

1.3

0.7817

Vedamanikam 2009

F

Chironomus

tentans

0.47

0.47

Ankley and Collyard 1995

F

Classenia

sabulosa

0.57

0.57

0.57

Sanders and Cope 1968; Johnson and Finley 1980;
Mayer and Ellersieck 1986

H

Pteronarcella

badia

0.38

0.38

0.38

Sanders and Cope 1968

H

Pteronarcys

californicus

10

10

10

Sanders and Cope 1968; Johnson and Finley 1980;
Mayer and Ellersieck 1986

E

Gammarus

fasciatus

0.32

0.32

0.1876

Sanders 1972

E

Gammarus

lacustris

0.11

0.11

Sanders 1969; Johnson and Finley 1980; Mayer and
Ellersieck 1986

E

Hyalella

azteca

0.04

0.0908

0.0908

Ankley and Collyard 1995

E

Hyalella

azteca

0.1192

Steevens 1999

E

Hyalella

azteca

0.2191

Steevens 1999

E

Hyalella

azteca

0.0651

Trimble andLydy 2006

E

Orconectes

immunis

6

6

6

Phipps and Holcombe 1985a; b

E

Procambarus

clarkii

21

21

21

Cebrianetal. 1992

E

Eriocheir

sinensis

22.9

63.91

63.91

Li et al. 2006

E

Eriocheir

sinensis

24.4

Li et al. 2006

E

Eriocheir

sinensis

75.9

Li et al. 2006

E

Eriocheir

sinensis

78.50

Li et al. 2006

E

Eriocheir

sinensis

142.2

Li et al. 2006

E

Eriocheir

sinensis

143.9

Li et al. 2006

B

Pimephales

promelas

170

194.1

194.1

Jarvinen and Tanner 1982

B

Pimephales

promelas

130

Jarvinen and Tanner 1982

B

Pimephales

promelas

122.2

Jarvinen et al. 1988

B

Pimephales

promelas

150

MRID 00154732; Jarvinen and Tanner 1982

B

Pimephales

promelas

140

Jarvinen and Tanner 1982; Office of Pesticide
Programs 2000

85


-------
()\\
MIJR

(iroup'1

(ionus

Species

I X 50/
I X 50
(MB/I.)

S\1 AY

(M8/U

(IMAY

(MS/'-)

Reference

B

Pimephales

promelas

120





Jarvinen and Tanner 1982; Office of Pesticide
Programs 2000

B

Pimephales

promelas

203.0

Holcombe et al. 1982; Office of Pesticide Programs
2000

B

Pimephales

promelas

542

Phipps and Holcombe 1985a; b

B

Pimephales

promelas

200

Geigeretal. 1988

B

Pimephales

promelas

506

Geigeretal. 1988

B

Gambusia

affinis

297.6

297.6

297.6

Rao et al. 2005

B

Pungitius

pungitius

4.7

4.7

4.7

Van Wijngaarden et al. 1993

B

Lepomis

macrochirus

2.4

3.281

3.281

Johnson and Finley 1980; Mayer and Ellersieck
1986

B

Lepomis

macrochirus

1.7

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

1.8

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

2.5

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

4.2

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

3

Alexander and Batchelder 1965; Office of Pesticide
Programs 2000

B

Lepomis

macrochirus

5.8

Bowman 1988b; Office of Pesticide Programs 2000

B

Lepomis

macrochirus

10

Phipps and Holcombe 1985a; b

B

Oreochromis

mossambica

4.8

11.12

11.12

Moorthy et al. 1982

B

Oreochromis

mossambica

25.78

Rao 2008

B

Tilapia

zillii

240

240

240

Shereif 1989

A

Oncorhynchus

clarkii

18.4

13.64

11.66

Johnson and Finley 1980

A

Oncorhynchus

clarkii

26

Mayer and Ellersieck 1986

A

Oncorhynchus

clarkii

5.4

Mayer and Ellersieck 1986

A

Oncorhynchus

clarkii

13.4

Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

7.1

9.97

Macek et al. 1969; Johnson and Finley 1980; Mayer
and Ellersieck 1986

A

Oncorhynchus

mykiss

15

Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

51

Mayer and Ellersieck 1986

86


-------
()\\
MDR

(iroup'1

(ionus

Species

I X 50/
I X 50
(MB/I.)

S\1 AY

(M8/U

(IMAY

(MS/'-)

Reference

A

Oncorhynchus

mykiss

1





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

25

Bowman 1988a; Office of Pesticide Programs 2000

A

Oncorhynchus

mykiss

8.0

Holcombe et al. 1982; Office of Pesticide Programs
2000

A

Oncorhynchus

mykiss

9

Phipps and Holcombe 1985a; b

A

Salvelinus

namaycush

98

150.0

150.0

Johnson and Finley 1980; Mayer and Ellersieck
1986

A

Salvelinus

namaycush

73

Mayer and Ellersieck 1986

A

Salvelinus

namaycush

140

Mayer and Ellersieck 1986

A

Salvelinus

namaycush

205

Mayer and Ellersieck 1986

A

Salvelinus

namaycush

227

Mayer and Ellersieck 1986

A

Salvelinus

namaycush

244

Mayer and Ellersieck 1986

B

Ictalurus

punctatus

280

475.1

475.1

Johnson and Finley 1980; Mayer and Ellersieck
1986

B

Ictalurus

punctatus

806

Phipps and Holcombe 1985a; b

B

Carassius

auratus

806

806

806

Phipps and Holcombe 1985a; b

B

Morone

saxatilis

1,000

1,000

1,000

Office of Pesticide Programs 2000

C

Xenopus

laevis

560

2,701

2,701

Richards 2000; Richards and Kendall 2002

C

Xenopus

laevis

14,600

Richards 2000; Richards and Kendall 2002

C

Xenopus

laevis

2,410

El-Merhibi et al. 2004

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species (e.g., bluegill, channel catfish,
etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

87


-------
OPP Acute Benchmark Values

The OPP invertebrate acute benchmark for chlorpyrifos is 0.05 |ig/L, which is V2 the lowest LC50
for Daphnia magna reported in U.S. EPA (2000).

The OPP fish acute benchmark for chlorpyrifos is 0.9 |ig/L, which is V2 the LC50 of 1.8 |ig/L for
Lepomis macrochirus reported in U.S. EPA (2000).

OW Acute Criterion

The acute criterion, or criterion maximum concentration (CMC), for chlorpyrifos is 0.083 |ig/L
(U.S. EPA 1986). The acute criterion dataset was smaller than the 2010 ECOTOX updated
dataset, and was comprised of 15 total genera, including 8 invertebrate genera.

Genus Level Invertebrate-only HC05

The genus-level invertebrate acute HC05 was calculated following the U.S. EPA (1985)
methodology for the 15 invertebrate genera (Table 2) in the combined chlorpyrifos dataset was
0.0580 |ig/L (Table 3).

Table 2. Chlorpyrifos invertebrate SMAVs and GMAVs (^ig/L).

(Ion us

Species

S.MAN'

CMAY

CMAY kiink

. Imb/cnia

p/icata

1,200

1,200

15

Aplexa

hypnorum

806.0

806.0

14

Eriocheir

sinensis

63.91

63.91

13

Procambarus

clarkii

21.00

21.00

12

Pteronarcys

californicus

10.00

10.00

11

Orconectes

immunis

6.000

6.000

10

Peltodytes

sp.

0.8000

0.8000

9

Chironomus

plumosus

1.300

0.7817

8

Chironomus

tentans

0.4700

Classenia

sabulosa

0.5700

0.5700

7

Pteronarcella

badia

0.3800

0.3800

6

Gammarus

fasciatus

0.3200

0.1876

5

Gammarus

lacustris

0.1100

Daphnia

ambigua

0.0350

0.1298

4

Daphnia

magna

0.4811

Hyalella

azteca

0.0908

0.0908

3

Simocephalus

vetulus

0.0900

0.0900

2

Ceriodaphnia

dubia

0.0627

0.0627

1

88


-------
Table 3. Genus level invertebrate-only acute HCos for chlorpyrifos calculated following the

N

Rank

(.MAY

ln(GMAV)

ln(GMAV)2

P=R/(N+1)

sqrt(P)

15

4

0.1298

-2.042

4.169

0.2500

0.5000



3

0.0908

-2.399

5.756

0.1875

0.4330



2

0.09

-2.408

5.798

0.1250

0.3536



1

0.0627

-2.769

7.670

0.0625

0.2500



Sum:



-9.618

23.39

0.6250

1.537







S2 =

7.621

L =

-3.465

A =

-2.848

hc05 =

0.0580

Table 4. Summary and comparison of acute values for chlorpyrifos.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

Pesticide

OPP Invertebrate ALB
(lowest LCso/2) (Year published,
species)

OW ALC (FAV/2) (Year
published, # of genera,
magnitude relative to ALB)

OW Genus level
Invertebrate-only HCos/2
(# of genera, magnitude
relative to ALB)

Chlorpyrifos

0.05 ng/L
(2000; D. magna)

0.083 ng/L

(1986 15 genera, 0.60X)

0.029 (ig/L
(15 genera, 1.7X)

Figure 1 shows a genus level sensitivity distribution for the full chlorpyrifos dataset. Major
taxonomic groups are delineated by different symbols, and invertebrate genera are identified by
name. The CMC, OPP acute benchmark values, and genus-level invertebrate only acute HCos/2
are included.

89


-------
10,000.00

1,000.00

100.00

u>
3
«/>
o

>
Q.

i—

o
u

•

Arthropod

o

Mollusk

¦

Salmonid Fish

~

Other Fish

A

Amphibian



Genus-level Invertebrate



OPP Benchmark

	

CMC

	

OPP Fish Benchmark

10.00

1.00

0.10

0.01

Amblema

~ o

~

o

~

X

~

¦

Eriocheir •

• Procambarus

~ o

~

Aplexa

Pteronarcys ^ ~ l
Orconectes

~

~

Chironomus

OPP Fish Benchmark = 0.9 pg/L

v - *:

Hyalella

^ *DapP

Classenia * ~ "Peltodytes

• Pteronarcella

Gammarus
Daphnia



Simocephalus

FAV/2 = Criterion Maximum Concentration = 0.083 pg/L
OPP Invertebrate Benchmark = 0.05 pg/L
	Genus-level Invertebrate HC05/2 = 0.0290 pg/L

Ceriodaphnia

o.o

o.i

0.2

0.3

0.4	0.5	0.6

Sensitivity Centile

0.7

0.8

0.9

1.0

Figure 1. Chlorpyrifos acute genus-level SD.

Symbols represent Genus Mean Acute Values (GMAVs) calculated using all available data from the chlorpyrifos ALC (U.S. EPA
1986), the Office of Pesticide Program's registration review document for chlorpyrifos (U.S. EPA 2000), and an ECOTOX search
conducted by Office of Water in 2010.

90


-------
1.1.6.2 Chlorpyrifos References

MRID 00102520: McCarty, W.M. 1977. Toxicity of chlorpyrifos to daphnids. Rep. ES-164. The
Dow Chemical Company. Midland, MI.

MRID 00154732: Jarvinen, A.W., and D.K. Tanner. 1982. Toxicity of Selected Controlled
Release and Corresponding Unformulated Technical Grade Pesticides to the Fathead Minnow
Pimephales promelas. Environ. Pollut. A. 27(3): 179-195. doi: 10.1016/0143-1471(82)90024-1.

MRID 40840902: Burgess, D. 1988. Acute flow-through toxicity of chlorpyrifos technical to
Daphnia magna. Report No. 37190. Prepared by Analytical Bio-Chemistry Laboratories, Inc.
Columbia, MO. Submitted by Makhteshim-Agan (America) Inc. New York, NY. Accession No.
408409-02.

Alexander, H.C.; Batchelder, T.L. 1965. Results of a Study on the Acute Toxicity of Dursban®
to Three Species of Fish. (Unpublished study received Jan 11, 1966 under 464-343; submitted by
Dow Chemical U.S.A., Midland, Mich.; CDL:003570-L).

Ankley, G.T., and S.A. Collyard. 1995. Influence of Piperonyl Butoxide on the Toxicity of
Organophosphate Insecticides to Three Species of Freshwater Benthic Invertebrates. Comp.
Biochem. Physiol. C Comp. Pharmacol. Toxicol. 110(2): 149-155.

Bailey, H.C., C. DiGiorgio, K. Kroll, J.L. Miller, D.E. Hinton, and G. Starrett. 1996.
Development of Procedures for Identifying Pesticide Toxicity in Ambient Waters: Carbofuran,
Diazinon, Chlorpyrifos. Environ. Toxicol. Chem. 15(6): 837-845. doi: 10.1002/etc.5620150604.

Bailey, H.C., J.L. Miller, M.J. Miller, L.C. Wiborg, L. Deanovic and T. Shed. 1997. Joint acute
toxicity of diazinon and chlorpyrifes to Ceriodaphnia dubia. Environ. Toxicol. Chem. 16:2304-
2308.

Bowman, J. 1988a. Acute Flow-Through Toxicity of Chlorpyrifos Technical to Bluegill
(Lepomis macrochirus): Project ID:37189. Unpublished study prepared by Analytical Bio-
Chemistry Laboratories, Inc. 188 p.

Bringolf, R.B., W.G. Cope, M.C. Barnhart, S. Mosher, P.R. Lazaro, and D. Shea. 2007. Acute
and Chronic Toxicity of Pesticide Formulations (Atrazine, Chlorpyrifos, and Permethrin) to
Glochidia and Juveniles of Lampsilis siliquoidea. Environ. Toxicol. Chem. 26(10): 2101-2107.
doi:10.1897/06-555R.l.

Cebrian, C., E.S. Andreu-Moliner, A. Fernandez-Casalderrey, andM.D. Ferrando. 1992. Acute
Toxicity and Oxygen Consumption in the Gills of Procambarus clarkii in Relation to
Chlorpyrifos Exposure. Bull. Environ. Contam. Toxicol. 49(1): 145-149.
doi:10.1007/BF00193353.

Diamantino, T.C., R. Ribeiro, F. Goncalves, and A.M.V.M. Soares. 1998. METIER (Modular
Ecotoxicity Tests Incorporating Ecological Relevance) for Difficult Substances. 5. Chlorpyrifos
Toxicity to Daphnia magna in Static, Semi-Static, and Flow-Through Conditions. Bull. Environ.
Contam. Toxicol. 61(4): 433-439. doi:10.1007/s001289900781.

Doran, W.J., W.G. Cope, R.G. Rada, and M.B. Sandheinrich. 2001. Acetylcholinesterase
Inhibition in the Threeridge Mussel (Amblema plicata) by Chlorpyrifos: Implications for
Biomonitoring. Ecotoxicol. Environ. Saf. 49(1): 91-98. doi:10.1006/eesa.2000.2036.

91


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El-Merhibi, A., A. Kumar, and T. Smeaton. 2004. Role of Piperonyl Butoxide in the Toxicity of
Chlorpyrifos to Ceriodaphnia dubia and Xenopus laevis. Ecotoxicol. Environ. Saf. 57(2): 202-
212. doi: 10.1016/S0147-6513(03)00082-4.

Federle, P.F., and W.J. Collins. 1976. Insecticide Toxicity to Three Insects from Ohio Ponds.
Ohio J. Sci. 76(1): 19-24.

Foster, S., M. Thomas, and W. Korth. 1998. Laboratory-Derived Acute Toxicity of Selected
Pesticides to Ceriodaphnia dubia. Australas. J. Ecotoxicol. 4(1): 53-59.

Gaizick, L., G. Gupta, and E. Bass 2001. Toxicity of Chlorypyrifos to Rana pipiens Embryos.
Bull. Environ. Contam. Toxicol. 66(3): 386-391. doi:10.1007/s00128-001-0017-y.

Geiger, D.L., D.J. Call, and L.T. Brooke. 1988. Acute Toxicities of Organic Chemicals to
Fathead Minnows (Pimephales promelas) Volume IV. Center for Lake Superior Environmental
Studies, University of Wisconsin, Superior, WI, 4, 355 p.

Harmon, S.M., W.L. Specht, and G.T. Chandler 2003. A Comparison of the Daphnids
Ceriodaphnia dubia and Daphnia ambigua for Their Utilization in Routine Toxicity Testing in
the Southeastern United States. Arch. Environ. Contam. Toxicol. 45(1): 79-85.
doi: 10.1007/s00244-002-0116-8.

Holcombe, G.W., G.L. Phipps and O.K. Tanner. 1982. The acute toxicity of kelthane, Oursban,
disulfoton, pydrin, and permethrin to fathead minnows Pimephales promelas and rainbow trout
Salmo gairdneri. Environ. Pollut. (Ser. A.) 29:167-178.

Johnson, W.W. and M.T. Finley. 1980. Handbook of acute toxicity of chemicals to fish and
aquatic invertebrates. Resource Publication 137.U.S. Fish and Wildlife Service, Washington,
DC. p. 21.

K. Li, L. Q. Chen, E. C. Li and Z. K. Zhou. 2006. Acute Toxicity of the Pesticides Chlorpyrifos
and Atrazine to the Chinese Mitten-handed Crab, Eriocheir sinensis. Bull. Environ. Contam.
Toxicol. 77:918-924.

Kersting, K., and R. Van Wijngaarden (1992). Effects of Chlorpyrifos on a Microecosystem.
Environ. Toxicol. Chem. 11 (3): 365-372. doi:10.1002/etc.5620110310.

Kikuchi, M., Y. Sasaki, and M. Wakabayashi. 2000. Screening of Organophosphate Insecticide
Pollution in Water by Using Daphnia magna. Ecotoxicol. Environ. Saf., 47, (3), 239-245.
doi: 10.1006/eesa.2000.1958.

Macek, K.J., C. Hutchinson and O.B. Cope. 1969. The effects of temperature on the
susceptibility of bluegills and rainbow trout to selected pesticides. Bull. Environ. Contam.
Toxicol. 4:174-183.

Mayer, F.L., Jr., and M.R. Ellersieck.1986. Manual of Acute Toxicity: Interpretation and Data
Base for 410 Chemicals and 66 Species of Freshwater Animals. USDI Fish and Wildlife Service,
Publication No. 160, Washington, DC, 505 p.

Moorthy, M.V., S. Chandrasekhar and V.R. Chandran. 1982. A note on acute toxicity of
chlorpyrifos to the freshwater fish Thilapia mossambica. Pesticides 16:32.

92


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Pablo, F., F.R. Krassoi, P.R.F. Jones, A.E. Colville, G.C. Hose, and R.P. Lim. 2008. Comparison
of the Fate and Toxicity of Chlorpyrifos - Laboratory Versus a Coastal Mesocosm System.
Ecotoxicol. Environ. Saf. 71(1): 219-229.

Palma, P., V.L. Palma, R.M. Fernandes, A.M.V.M. Soares, and I.R. Barbosa. 2008. Acute
Toxicity of Atrazine, Endosulfan Sulphate and Chlorpyrifos to Vibrio fischeri, Thamnocephalus
platyurus and Daphnia magna, Relative to Their Concentrations in Surface Waters from the
Alentejo Region of Portugal. Bull. Environ. Contam. Toxicol. 81(5): 485-489.
doi: 10.1007/s00128-008-9517-3.

Phipps, G.L. and G.W. Holcombe. 1985a. A method for aquatic multiple species toxicant testing.
Acute toxicity of 10 chemicals to 5 vertebrates and 2 invertebrates. Environ. Pollut. (Series A)
38:141-157.

Phipps, G.L. and G.W. Holcombe. 1985b. U.S. EPA, Duluth, MM. (Memorandum to C.E.
Stephan, U.S. EPA, Duluth, MH. October 22.

Rao, J. V. 2008. Brain Acetylcholinesterase Activity as a Potential Biomarker for the Rapid
Assessment of Chlorpyrifos Toxicity in a Euryhaline Fish, Oreochromis mossambicus. Environ.
Bioindic. 3(1): 11-22.

Richards, S.M. 2000. Chlorpyrifos: Exposure and Effects in Passerines and Anurans. Ph.D
Thesis, Texas Tech University, Lubbock, TX, 147 p.

Richards, S.M., and R.J. Kendall. 2002. Biochemical Effects of Chlorpyrifos on Two
Developmental Stages of Xenopus laevis. Environ. Toxicol. Chem. 21(9): 1826-1835.

Sanders, H.O. 1969. Toxicity of Pesticides to the Crustacean Gammarus lacustris.
Tech.Pap.No.25, U.S.D.I., Bur. Sports Fish. Wildl., Fish Wildl. Serv., Washington, DC, 18 p.

Sanders, H.O. 1972. Toxicity of some insecticides to four species of malacostracan crustaceans.
Technical Paper No. 66. U.S. Fish and Wildlife Service, Washington, DC.

Sanders, H.O. and O.B. Cope. 1968. The relative toxicities of several pesticides to naiads of
three species of stoneflies. Limnol. Oceanogr. 13:112-117

Shereif, M.M. 1989. Acute and Chronic Effects of Chlorpyrifos on Tilapia zillii. Ph.D. Thesis,
Michigan State University, East Lansing, MI, 114 p.

Steevens, J.A. 1999. Chemical Mixture Interactions: Toxicity of Chlorpyrifos, Dieldrin, and
Methyl Mercury to the Amphipod Hyalella azteca. Ph.D Thesis, University of Mississippi,
University, MS, 183 p.

Trimble, A.J., and M.J. Lydy (2006). Effects of Triazine Herbicides on Organophosphate
Insecticide Toxicity in Hyalella azteca. Arch. Environ. Contam. Toxicol. 51(1): 29-34.
doi: 10.1007/s00244-005-0176-7.

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

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U.S. EPA. 1986. Ambient water quality criteria for chlorpyrifos - 1986. Office of Water
Regulations And Standards Criteria and Standards Division. Washington, DC. EPA 440/5-86-
005. September 1986.

U.S. EPA 2000. Reregi strati on eligibility science chapter for chlorpyrifos. Fate and
environmental risk assessment chapter. June 2000.

U.S. EPA. 2001. Office of Pesticide Programs Annual Report 2000. Office of Chemical Safety
and Pollution Prevention formerly the Office of Prevention, Pesticides and Toxic Sustances,
Washington DC. EPA 735-R-00-002. August 2001.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

Van Wijngaarden, R., P. Leeuwangh, W.G.H. Lucassen, K. Romijn, R. Ronday, and R. Van der
Velde. 1993. Acute Toxicity of Chlorpyrifos to Fish, a Newt, and Aquatic Invertebrates. Bull.
Environ. Contam. Toxicol. 51(5): 716-723.

Vedamanikam, V.J. 2009. Formation of Resistance in the Chironomus plumosus to Four
Pesticides over 45 Generations. Toxicol. Environ. Chem. 91(1): 187-194.

94


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1.1.7 Comparison of Aquatic Life Toxicity Values for Dichlorvos: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA) (U.S. EPA 2024) for dichlorvos were gathered from the OPP
registration review document for dichlorvos (U.S. EPA 2009) and an EPA ECOTOX
Knowledgebase search conducted in 2013. There was no comparative analysis for dichlorvos
chronic data.

1.1.7.1 Dichlorvos Acute Toxicity Data

Acute data were gathered from the Office of Pesticide Programs (OPP) registration review
document for dichlorvos (U.S. EPA 2009) and an ECOTOX search conducted in 2013 (see Table

1).

The dichlorvos acute dataset consisted of 27 acceptable acute effect LCsos for 15 total species
across 12 genera, of which eight were vertebrate species across six invertebrate genera. Ranked
invertebrate GMAVs are listed in Table 4.

Table 1. Acute toxicity data of dichlorvos to freshwater at

()\\
MI)R

(iroiip-1

(ion us

Species

I X 50/
I X 50
(MS/'-)

S\1 AY

(MS/'-)

(IMAY

(MS/'-)

Reference

G

Lumbriculus

variegatus

2,180

2,180

2,180

Brooke 1991

G

Physa

sp.

170

170

170

Brooke 1991

D

Daphnia

magna

0.266

0.266

0.1333

Brooke 1991

D

Daphnia

pulex

0.0668

0.0668

Mayer and Ellersieck 1986

D

Simocephalus

serrulatus

0.28

0.2698

0.2698

Mayer and Ellersieck 1986

D

Simocephalus

serrulatus

0.26

Mayer and Ellersieck 1986

F

Pteronarcys

californica

0.1

0.1

0.1

Mayer and Ellersieck 1986

E

Gammarus

fasciatus

0.4

0.4

0.4472

Sanders 1972

E

Gammarus

lacustris

0.5

0.5

Mayer and Ellersieck 1986

B

Pimephales

promelas

4,000

5,234

5,234

Pickering and Henderson 1966

B

Pimephales

promelas

11,600

Mayer and Ellersieck 1986

B

Pimephales

promelas

3,090

Brooke 1991

B

Gambusia

affinis

5,270

5,270

5,270

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

869

445.6

445.6

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

480

Cope 1965

B

Lepomis

macrochirus

350

Pickering and Henderson 1966

B

Lepomis

macrochirus

270

Pickering and Henderson 1966

B

Tilapia

mossambica

1,934

1,671

1,671

Rath and Misra 1979

B

Tilapia

mossambica

1,710

Rath and Misra 1979

B

Tilapia

mossambica

1,410

Rath and Misra 1979

A

Oncorhynchus

clarki

170

199.8

141.4

Mayer and Ellersieck 1986

uatic organisms.

95


-------
OW
MIJR

(ironp'1

(ion us

Species

l .( 50/
IX 50

(M8/U

SMAV
(MS/'-)

(IMAY

(MS/'-)

Reference

A

Oncorhynchus

clarki

170





Mayer and Ellersieck 1986

A

Oncorhynchus

clarki

170

Mayer and Ellersieck 1986

A

Oncorhynchus

clarki

213

Mayer and Ellersieck 1986

A

Oncorhynchus

clarki

304

Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

100

100

Stalin and Johnson 1977

A

Salvelinus

namaycush

187

185.0

185.0

Mayer and Ellersieck 1986

A

Salvelinus

namaycush

183

Mayer and Ellersieck 1986

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important

warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Acute Benchmark Values

The OPP invertebrate acute benchmark is 0.0334 |ig/L, which is V2 of the D. pulex LC50 of
0.0668 |ig/L reported in Mayer and Ellersieck (1986).

The OPP fish acute benchmark is 50 |ig/L, which is V2 of the 0. mykiss LC50 of 100 |ig/L
reported in Stalin and Johnson (1977).

OW Acute Criterion

There is no acute criterion, or criterion maximum concentration (CMC), for dichlorvos. An
illustrative example was calculated for this analysis, using all available data (Table 2). The
illustrative FAV calculated calculated following the U.S. EPA (1985) methodology for the 12
genera in the dichlorvos dataset was 0.06330 |ig/L (Table 3).

Table 2. Dichlorvos Ranked Species Mean Acute Values (SMAV) and Genus Mean Acute
Values (GMAV).					

(icmis

Species

SMAV
(Mli/U

(IMAY
(Mli/U

CMAY kiink

(jamb u si a

affinis

s,-"0

s,-"0

i:

Pimephales

promelas

5,234

5,234

11

Lumbriculus

variegatus

2,180

2,180

10

Tilapia

mossambica

1,671

1,671

9

Lepomis

macrochirus

445.6

445.6

8

Salvelinus

namaycush

185.0

185.0

7

Physa

sp.

170.0

170.0

6

Oncorhynchus

clarki

199.8

141.3

5

Oncorhynchus

mykiss

100

96


-------
(Jen lis

Species

S\1 AY

(nii/U

(IMAY

(uii/l.)

(IMAY kiink

Gammarus

fasciatus

0.4000

0.4472

4

Gammarus

lacustris

0.5000

Simocephalus

serrulatus

0.2698

0.2698

3

Daphnia

magna

0.2660

0.1333

2

Daphnia

pulex

0.0700

Pteronarcys

californica

0.1000

0.1000

1

Table 3. Dichlorvos Illustrat

ive FAV/2







.V

Kiink

(;m ay

ln((;\l.\Y)

lii((i MAN )"

P=R/(\+l)

S(|I|(P)

12

4

0.4472

-0.805

0.648

0.3077

0.5547



3

0.2698

-1.310

1.716

0.2308

0.4804



2

0.1333

-2.015

4.061

0.1538

0.3922



1

0.1000

-2.303

5.302

0.0769

0.2774



Sum:



-6.433

11.73

0.769

1.705



s2 =

32.326





L =

-4.031





A =

-2.760



FAV =

0.06330



FAV/2

0.032



Genus Level Invertebrate-only HCos

The genus level invertebrate-only acute HCos calculated following the U.S. EPA (1985)
methodology for the six invertebrate genera (Table 4) in the dichlorvos dataset was 0.04513 |ig/L
(Table 5).

Table 4. Dichlorvos invertebrate SMAVs and GMAVs

(¦onus

Species

SM AY

(IMAY

(i.MAY K;ink

Lumbriculus

variegatus

2,180

2,180

6

Physa

sp.

170.0

170.0

5

Gammarus

fasciatus

0.4000

0.4472

4

Gammarus

lacustris

0.5000

Simocephalus

serrulatus

0.2698

0.2698

3

Daphnia

magna

0.2660

0.1365

2

Daphnia

pulex

0.0668

Pteronarcys

californica

0.1000

0.1000

1

Hg/L)-

97


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Table 5. Genus-level invertebrate acute HCos for dichlorvos calculated using following the
U.S. EPA (1985) methodology.				

N

Rank

GMAV

ln(GMAV)

ln(GMAV)2

P=R/(N+1)

sqrt(P)

6

4

0.4472

-0.805

0.648

0.5714

0.7559



3

0.2698

-1.310

1.716

0.4286

0.6547



2

0.1333

-2.015

4.061

0.2857

0.5345



1

0.1000

-2.303

5.302

0.1429

0.3780



Sum:



-6.433

11.73

1.429

2.323











S2 =

17.406











L =

-4.031











A =

-3.098











hc05 =

0.04513









Table 6. Summary and comparison of acute values for dichlorvos.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio >1 indicates the OPP value is higher than the OW value.	

Pesticide

OPP Invertebrate
ALB

(lowest LCso/2) (Year
published, species)

OW Illustrative ALC (FAV/2)
(Year published, # of genera,
magnitude relative to ALB)

OW Genus-level
Invertebrate-only HCos/2
(# of genera, magnitude
relative to ALB)

Dichlorvos

0.0334 ng/L
(2021; D. pulex)

0.032 ng/L

(illustrative example calculated for
this analysis, 12 genera, 1.1X)

0.023 ng/L
(6 genera, 1.5X)

Figure 1 shows a genus level sensitivity distribution for the dichlorvos dataset. Major taxonomic
groups are delineated by different symbols, and invertebrate genera are identified by name. Lines
denoting the OPP acute benchmark values, illustrative ALC example, and invertebrate-only
acute HC05/2 are included.

98


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10,000.00

1,000.00

100.00

QUO

3

(/>
o
>

_o

u

b

10.00

1.00

0.10

o
¦

~
A

Arthropod
Mollusk
Salmonid Fish
Other Fish
Other Invertebrate

FAV/2 = "Criterion Maximum Concentration"
•Genus-level Invertebrate HC05/2
OPP Invertebrate Benchmark
OPP Vertebrate Benchmark

~

~ ~
^ Lumbriculus

~

o

OPP Vertebrate Benchmark = 50 ng/L

• Gammarus
• Simocephalus

Pteronarcys

• Daphnia

OPP Invertebrate Benchmark = 0.035 [ig/L'

0.01

Genus-level Invertebrate FIC05/2 = 0.023 |ig/L '

FAV/2 = "Criterion Maximum Concentration" = 0.032 ng/L

/

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

Sensitivity Centile

Figure 1. Dichlorvos genus-level acute SD.

Symbols represent Genus Mean Acute Values (GMAVs) calculated using all available data from the Office of Pesticide Program's
registration review document for dichlorvos (U.S. EPA 2009) and an ECOTOX search conducted by Office of Water in 2013.
Dichlorvos does not have a recommended 304(a) aquatic life criteria. The "Criterion Maximum Concentration" is an illustrative
example calculated for these analyses.

99


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1.1.7.2 Dichlorvos References

Brooke, L.T. 1991. Results of Freshwater Exposures with the Chemicals Atrazine, Biphenyl,
Butachlor, Carbaryl, Carbazole, Dibenzofuran, 3,3'-Dichlorobenzidine, Dichlorvos, 1,2-
Epoxyethylbenzene (Styrene Oxide), Isophorone, Isopropalin, Ox. Center for Lake Superior
Environmental Studies, University of Wisconsin, Superior, WI, 110 p. ECOREF#: 17138.

Cope, O.B. 1965. Sport Fishery Investigations. Fish and Wildlife Service Circular 226, Effects of
Pesticides on Fish and Wildlife. Washington, DC, 51-63. ECOREF#: 2871.

Mayer, F.L., Jr., and M.R. Ellersieck. 1986. Manual of Acute Toxicity: Interpretation and Data
Base for 410 Chemicals and 66 Species of Freshwater Animals. USDI Fish and Wildlife Service,
Publication No. 160, Washington, DC, 505 p. ECOREF#: 6797.

Pickering, Q.H., and C. Henderson. 1966. The Acute Toxicity of Some Pesticides to Fish. Ohio
J. Sci., 66, (5), 508-513. ECOREF#: 8096.

Rath, S., and B.N. Misra. 1979. Relative Toxicity of Dichlorvos (DDVP) to Tilapia mossambica,
Peters of 3 Different Age Groups. Exp. Gerontol., 14, 307-309. doi: 10.1016/0531 -
5565(79)90042-1. ECOREF#: 17133.

Sanders, H.O. 1972. Toxicity of Some Insecticides to Four Species of Malacostracan
Crustaceans. Tech. Pap. Bur. Sport Fish. Wildl., 66, 19 p. ECOREF#: 887.

Stalin, A.M. and W.W. Johnson. 1977. Static Toxicity Tests, Fish Toxicity. Pesticide Research
Laboratory, Columbia, MO (undated) (111-39 - 111-44).

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2009. Registration review. Ecological risk assessment problem formulation for:
dichlorvos (DDVP). Office of Pesticide Programs. May 14, 2009.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

100


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1.1.8 Comparison of Aquatic Life Toxicity Values for Acrolein: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
(CWA) (U.S. EPA 2024) for acrolein were obtained from Table 1 of the acrolein freshwater
aquatic life criteria (ALC) document (U.S. EPA 2009a). There was no comparative analysis for
chronic acrolein values.

1.1.8.1 Acrolein Acute Toxicity Data

Acceptable acute data for acrolein were obtained from Table 1 of the acrolein freshwater aquatic
life criteria (ALC) document (U.S. EPA 2009a). Data were available for 36 acute tests
encompassing 15 species and 14 genera. Data for invertebrate taxa were available for 12 acute
tests encompassing seven species and seven genera. The OPP benchmark document (2009b) was
examined to determine whether any additional acute tests were available that were not included
in the criteria document. All values in the OPP benchmark document were included in Table 1 of
the acrolein ALC. Ranked invertebrate GMAVs are listed in Table 2.

Table 1. Acute toxicity da

a of acrolein to freshwater aquatic organisms.

()\\
MIJR

(iroup'1

(ion us

Species

l .( 50/
I X 50

(M8/I-)

S\1 AY

(M8/U

(IMAY

(MJi/l)

Reference

G

Aplexa

hypnorum

>151

>151

>151

Holcomb et al. 1987

G

Physa

heterostropha

368

368

368

Home and Oblad 1983

D

Daphnia

magna

57

61.79

61.79

Maceketal. 1976

D

Daphnia

magna

80

USEPA 1978

D

Daphnia

magna

93

Randall and Knopp 1980

D

Daphnia

magna

83

LeBlanc 1980

D

Daphnia

magna

51

Holcomb et al. 1987

D

Daphnia

magna

<31

Blakemore 1990

E

Gammarus

minus

180

180

180

Home and Oblad 1983

H

Peltoperla

maria

5,920

5,920

5,920

Home and Oblad 1983

F

Chironomus

riparius

510

510

510

Home and Oblad 1983

F

Tanytarsus

dissimilis

>151

>151

>151

Holcomb et al. 1987

A

Oncorhynchus

kisutch

68

68

57.05

Lorz et al. 1979

A

Oncorhynchus

mykiss

74

47.86

Birge et al. 1982

A

Oncorhynchus

mykiss

180

Home and Oblad 1983

A

Oncorhynchus

mykiss

38

Venturino et al. 2007

A

Oncorhynchus

mykiss

<31

Bowman 1990a

A

Oncorhynchus

mykiss

16

Holcomb et al. 1987

B

Pimephales

promelas

320

35.79

35.79

Union Carbide Corp. 1974

B

Pimephales

promelas

45

Birge et al. 1982

B

Pimephales

promelas

14

Geigeretal. 1986

B

Pimephales

promelas

19.5

Geigeretal. 1986

B

Pimephales

promelas

61

Birge et al. 1982

101


-------
OW
MIJR

Group-'

(ion us

Species

IX 50/
I X 50
(Mii/U

S\1 AY

(M8/U

GMAY
(MS/'-)

Reference

B

Pimephales

promelas

29.7





Sabourin 1986

B

Pimephales

promelas

27

Spehar 1989

B

Pimephales

promelas

14

Holcometal. 1987

B

Catostomus

commersoni

14

14

14

Holcomb et al. 1987

B

Jordanella

floridae

60

55.32

55.32

Spehar 1989

B

Jordanella

floridae

51

Spehar 1989

B

Lepomis

macrochirus

100

56.94

56.94

Louder and McCoy 1962

B

Lepomis

macrochirus

90

USEPA 1978

B

Lepomis

macrochirus

90

Buccafusco et al. 1981

B

Lepomis

macrochirus

33

Holcomb et al. 1987

B

Lepomis

macrochirus

22.4

Bowman 1990b

B

Micropterus

salmoides

160

160

160

Louder and McCoy 1962

C

Xenopus

laevis

7

7

7

Holcomb et al. 1987

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important
warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Acute Benchmark Values

The OPP invertebrate acute benchmark for acrolein is <15.5 |ig/L, which is V2 the lowest LC50
for Daphnia magna. This is also the lowest LC50 for D. magna reported in Table 1 of the ALC
document.

The OPP vertebrate acute benchmark for acrolein is 3.5 |ig/L, which is V2 the lowest LC50 for the
African clawed frog, Xenopus laevis.

OW Acute Criterion

The criterion maximum concentration (CMC) for acrolein is 3.0 |ig/L.

Genus Level Invertebrate-only HC05

The genus level invertebrate-only acute HC05 calculated following the U.S. EPA (1985)
methodology for the seven invertebrate genera (Table 2) in the acrolein dataset was 45.74 |ig/L
(Table 3).

Table 2. Acrolein Invertebrate SMAVs and GMAVs (^ig/L).

Genus

Species

SMAV

GMAV

GMAV Rank

Tallaperla"

maria

5,920

5,920

7

102


-------
Genus

Species

SMAV

GMAV

GMAV Rank

Chironomus

ripar ins

510.0

510.0

6

Phvsa

heterostropha

368.0

368.0

5

Gammarus

minus

180.0

180.0

4

Aplexa

hvpnorum

151.0

151.0

3

Tanvtarsus

dissimilis

151.0

151.0

2

Daphnia

magna

61.79

61.79

1

a - Genus changed from Peltoperla

Table 3. Genus level invertebrate-only acute HCos for acrolein calculated following the U.S.
EPA (1985) methodology.

N

Rank

GMAV

ln(GMAV)

ln(GMAV)2

P=R/(N+1)

sqrt(P)

7

4

180

5.193

26.97

0.5000

0.7071



3

151

5.017

25.17

0.3750

0.6124



2

151

5.017

25.17

0.2500

0.5000



1

61.79

4.124

17.01

0.1250

0.3536



Sum:



19.35

94.3

1.250

2.173







S2 =

10.08

L =

3.113

A =

3.823

hc05 =

45.74

Table 4. Summary and comparison of acute values for acrolein.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

ratio >1 indicates the OPP value is hig

ier than the OW value.

Pesticide

OPP Most Sensitive ALB
(lowest LCso/2) (Year
published, species)

OW ALC (FAV/2)
(Year published, # of
genera, magnitude relative
to ALB)

OW Genus-level Invertebrate-

only HCos/2
(# of genera, magnitude relative
to ALB)

Acrolein

(contact

herbicide)

3.5 ng/L

(2023; Xenopus laevis)

3.0 ng/L

(2009, 14 genera, 1.2X)

22.87 ng/L

(7 genera, 0.68X)

Note the magnitude comparison is

with the invertebrate ALB of

<15.5 ng/L.

Figure 1 shows a genus-level sensitivity distribution for the full acrolein dataset. Major
taxonomic groups are delineated by different symbols, and invertebrate genera are identified by
name. The CMC, OPP invertebrate and vertebrate acute benchmark values, and invertebrate-only
acute HC05/2 are included.

103


-------
10,000

1,000

bO

3
c

Jj
o

k_

u
<

100

•

Arthropod

o

Mollusk

¦

Salmonid Fish

~

Other Fish

A.

Amphibian



Genus-level Invertebrate



OPP Invert. Benchmark

	

CMC



OPP Vertebrate Benchmark

Peltoperla •

• Chironomus

~

~

Tanytarsus • o
Aplexa

• Daphnia

~

O Physa
• Gammarus

~

Genus-level invertebrate HC05/2= 22.87 |ig/L

~

10

OPP Invertebrate Benchmark = <15.5 |ig/L

OPP Vertebrate Benchmark = 3.5 |ig/L
FAV/2 = Criterion Maximum Concentration = 2.96 |ig/L

0.0

0.1

0.2

0.3

0.4	0.5	0.6

Sensitivity Centile

0.7

0.8

0.9

1.0

Figure 1. Acrolein genus-level acute SD.

Symbols represent GMAVs calculated using all available data from Table 1 of the 2009 acrolein ALC.

104


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1.1.8.2 Acrolein References

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2009a. Ambient aquatic life water quality criteria for acrolein. Office of Water.
Washington D.C. EPA 822R0819. July 1, 2009.

U.S. EPA. 2009b. Environmental fate and ecological risk assessment for the reregi strati on of
acrolein. Office of Pesticide Programs. Washington, D.C. 20460.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

105


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1.2 Data-Limited Pesticides

1.2.1 Comparison of Aquatic Life Toxicity Values for Oxamyl: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
(CWA) (U.S. EPA 2024) are described below. Toxicity data for oxamyl were gathered by OW in
2015 and combined with data from OPP's registration review document for oxamyl (U.S. EPA
2009).

1.2.1.1 Oxamyl Acute Toxicity Data

The oxamyl acute data include nine LCsos representing six species in six genera that were
classified as "quantitative" data, and two 96-hour LCsos for the amphipod species Gammarus
italicus and Echinogammarus tibaldii (classified as qualitative, but included in this analysis to
increase the number of invertebrate genera to four), thereby enabling calculation of an
invertebrate only genus-level HCos. Tests were classified as qualitative because both the G.
italicus andE. tibaldi studies were conducted with field-collected organisms, and the G. italicus
study was not replicated.

The final acute oxamyl dataset consisted of 11 LCsos for eight species across eight genera, of
which four were invertebrate species and four were invertebrate genera. Acute data for oxamyl
are shown in Table 1. Ranked invertebrate GMAVs are listed in Table 2.

106


-------
Table 1. Acute toxicity of oxamyl to freshwater aquatic organisms.

()\\
MDR
(iroup1

(Ionus

Species

IX 50/
I X 50
(Mli/U

S\1 AY

(MS/'-)

(IMAY

(MS/'-)

Reference

Comment

D

Daphnia

magna

320.0

387.8

387.8

MRID 45067801; Boeri and Ward. 2000

Quantitative

D

Daphnia

magna

470.0

ECOTOX 6797; Mayer and Ellersieck. 1986

Quantitative

F

Chironomus

plumosus

180.0

180.0

180.0

ECOTOX 6797; Mayer and Ellersieck. 1986

Quantitative

E

Echinogammarus

tibaldii

297.0

297.0

297.0

ECOTOX 18621; Pantani et al. 1997

Qualitative

E

Gammarus

italicus

217.8

217.8

217.8

ECOTOX 18621; Pantani et al. 1997

Qualitative

B

Carassius

auratus

27,500

27,500

27,500

MRID 66915; Knott and Johnston. 1969

Quantitative

C

Lepomis

macrochirus

5,600

7,483

7,483

MRID 66914; Knott and Johnston. 1969

Quantitative

C

Lepomis

macrochirus

10,000

ECOTOX 6797; Mayer and Ellersieck. 1986

Quantitative

A

Oncorhynchus

mykiss

4,200

4,200

4,200

MRID 66916; Knott and Johnston. 1969

Quantitative

A

Oncorhynchus

mykiss

4,200

ECOTOX 6797; Mayer and Ellersieck. 1986

Quantitative

B

Ictalurus

punctatus

19,400

19,400

19,400

ECOTOX 6797; Mayer and Ellersieck. 1986

Quantitative

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species (e.g., bluegill, channel catfish,

etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

107


-------
OPP Acute Benchmark Values

The OPP invertebrate acute benchmark for oxamyl is 90 |ig/L, which is V2 of the Chironomus
plumosus acute effect LC50 of 180 |ig/L.

The OPP fish acute benchmark is 2,100 |ig/L, which is V2 of one of the two Oncorhynchus
mykiss acute LC50S of 4,200 |ig/L.

GLI Tier II Acute Value Calculation

The acceptable dataset for oxamyl fulfills six of the eight OW MDRs, corresponding to the use
of a Secondary Acute Factor (SAF) of 5.2. Applying the SAF to the lowest (most sensitive)
GMAV (i.e., 180 |ig/L for midge (Chironomuspulmosus)) yields the calculated Secondary Acute
Value (SAV) of34.6 |ig/L. Half of the SAV is 17.3 |ig/L.

Detailed calculations are shown below:

SAV =

Lowest GMAV

SAF

180

SAV = — = 34.6 |xg/L

SMC =

5.2
SAV

34.6

SMC =—-= 17.3 \ig/L

Genus-Level Invertebrate-only HC05

The genus level invertebrate-only acute HC05 calculated following the U.S. EPA (1985)
methodology for the four invertebrate genera in the oxamyl dataset (Table 2) is 114.7 |ig/L
(Table 3).

Table 2. Oxamyl invertebrate SMAVs and GMAVs (ng/L).

(Ion us

Species

S\1 AY

(IMAY

CMAY kiink

Daphnia

magna

387.8

387.8

4

Echinogammarus

tibaldii

297.0

297.0

3

Gammarus

italicus

217.8

217.8

2

Chironomus

plumosus

180.0

180.0

1

Note: The G. italicus and E. tibaldii GMAVs are based on data classified as qualitative that were included to allow
for sufficient sample size to calculate an invertebrate genus-level HC05.

108


-------
Table 3. Genus-level invertebrate-only acute HCos for oxamyl calculated following the U.S.
EPA (1985) methodology.

N

Rank

(.MAY

ln(GMAV)

ln(GMAV)2

P=R/(N+1)

s qrt(P)

4

4

387.8

5.961

35.53

0.8000

0.8944



3

297

5.694

32.42

0.6000

0.7746



2

217.8

5.384

28.98

0.4000

0.6325



1

180

5.193

26.97

0.2000

0.4472



Sum:



22.23

123.9

2.000

2.749







S2 =

3.095

L =

4.349

A =

4.742

hc05

114.7

Table 4. Comparison of acute values for oxamyl.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio >1 indicates the OPP value is higher than the OW value.	

Pesticide

OPP

Invertebrate

ALB
(lowest LCso/2)
(Year published,
species)

OW GLI Tier
II value (# of
MDRs filled,
magnitude
relative to
ALB)

OW Genus-level
Invertebrate-only
HCos/2
(# of genera,
magnitude relative
to ALB)

Notes

Oxamyl

90 (ig/L
(2016;

Chironomus
plumosus)

17.3 ng/L
(6 MDRs filled,
5.2X)

57.35 (ig/L
(4 genera*, 1.6X)

* Two GMAVs included are
based on data classified as
qualitative were included to
allow for sufficient sample size
to calculate an invertebrate
genus-level HCos. Tests were
classified as qualitative because
they were conducted with field-
collected organisms.

Figure 1 shows a genus-level sensitivity distribution for the oxamyl dataset. Major taxonomic
groups are delineated by different symbols, and invertebrate genera are identified by name. Lines
denoting the OPP acute benchmark values, GLI Tier II calculated acute value, and invertebrate-
only acute HC05/2 are included.

109


-------
100,000

10,000

•	Arthropod

O Arthropod (Qualitative)
¦ Salmonid Fish

~	Other Fish

	GL1 Tier II Acute Value

	Genus-level Invertebrate

		OPP Invertebrate Benchmark

— * • OPP Fish Benchmark

1,000

W

=L

>
E

s

o

100

10

0.0

OPP Fish Benchmark = 2,100 pg/L

• Chironomus

O Gammarus

• Daphnia
° Echinogammarus

OPP Invertebrate Benchmark = 90 pg/L

Genus-level Invertebrate HCO5/2 = 57.35 pg/L
GLI Tier II Acute Value = 17.3 pg/L

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

Sensitivity Centile

Figure 1. Oxamyl genus-level acute SD.

Symbols represent Genus Mean Acute Values (GMAVs) calculated using all available data from an EPA literature search in 2015,
supplemented the Office of Pesticide Programs (OPP) registration review document for oxamyl (U.S. EPA 2009).

110


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1.2.1.2 Oxamyl Chronic Toxicity Data
Chronic Data Sources and Considerations

Chronic toxicity data for oxamyl were consolidated by OW in 2015 and combined with data
from OPP's registration review document for oxamyl (U.S. EPA 2009). The final chronic
oxamyl dataset consisted of three NOECs/LOECS for three species across three genera, of which
one was an invertebrate genus and two were vertebrate genera (Table 5).

Table 5. Chronic toxicity data of oxamyl to freshwater aquatic organisms.

OW
MIJR

(i rou p'1

(Ionus

Species

NOW

(MS/'-)

I.OKC
(MS/I-)

Lnclpoint

Reference

Comment

D

Daphnia

magna

27

50

Growth (adult length),
time to first brood and
number of offspring

MRID 45067801;
Boeri and Ward.
2000

Acceptable

A

Oncorhynchus

mykiss

770

1,500

Embryo hatching and
larval swim-up

MRID 40901101;
Hutton. 1988

Acceptable

B

Pimephales

promelas

500

1,000

Larval survival

MRID 94663;
Muska and Driscoll.
1982

Acceptable

t MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species

(e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Chronic Benchmark Values

The OPP invertebrate chronic benchmark for oxamyl is 27 |ig/L, which is the NOEC for
Daphnia magna. The OPP fish chronic benchmark is 500 |ig/L, which is the NOEC for
Pimephales promelas.

GLI Tier II Chronic Value Calculation

Per the 1985 Tier I Guidelines, ACRs can be calculated for a given species only if the acute and
chronic studies were conducted in the same laboratory and using test water of the same physical
and chemical characteristics. The OW approach for calculating an ACR involves the use of the
MATC, which is the geometric mean of the NOAEC and LOAEC obtained from the chronic
tests for that species. Only one ACR (for the water flea, Daphnia magna) could be calculated
using the OW approach because the chronic study for rainbow trout (iOncorhynchus mykiss) was
not performed in the same laboratory or with water of the same physical characteristics as the
water used in the analogous acute test. Per the GLI Tier II methodology, the default ACR value
of 18 was used for the remaining two ACRs.

Ill


-------
Detailed calculations for the SC V are shown below:

= Geometric Mean of the ACRs
= V8.71 * 18 * 18 = 14.1

SACR
34.6

iU = 24 w/l

Table 6. Comparison of chronic values for oxamyl.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio >1 indicates the OPP value is higher than the OW value.	

Pesticide

OPP Invertebrate

ALB
(NOAEC) (Year
published, species)

OWGLI Tier II value
(# of ACRs filled,
magnitude relative to ALB)

OW Invertebrate-only
HCos
(# of ACRs filled,
magnitude relative to
ALB)

Notes

Oxamyl

27 (ig/L
(2016; Daphnia
magna)

2.4 (ig/L

(GLI Tier II; 1 ACR, 11X)

NA

Two default ACRs
of 18 used to derive
GLI Tier II value

1.2.1.3 Oxamyl References

ECOTOX 18621. Pantani, C., Pannunzio, G., De Cristofaro, M., Novelli, A. A., and Salvatori,
M. 1997. Comparative Acute Toxicity of Some Pesticides, Metals, and Surfactants to Gammarus
italicus Goedm. and Echinogammarus tibaldii Pink, and Stock (Crustacea: Amphipoda). Bull.
Environ. Contam. Toxicol. 59: 963-967.

ECOTOX 6797. Mayer, F. L. J., and Ellersieck, M. R. 1986. Manual of Acute Toxicity:
Interpretation and Data Base for 410 Chemicals and 66 Species of Freshwater Animals. Resour.
Publ. No. 160, U.S. Department of Interior, Fish and Wildlife Services, Washington, DC 505 p.

MRID 40901101. Hutton, D. 1988. Early Life Stage Toxicity of IN D1410-196 (Oxamyl) to
Rainbow Trout: Medical Research Project No. 4581-573: Haskell Laboratory Report No. 468-88.
Unpublished study prepared by E. I. du Pont de Nemours and Co., Inc. 24 p.

MRID 45067801. Boeri, R., and Ward, T. 2000. Oxamyl Technical: 21-Day Chronic, Flow-
Through Toxicity to Daphnia magna: Lab Project Number: 3 10: 1757-DU: 2554. Unpublished
study prepared by T.R. Wilbury Labs. 60 p.

MRID 66914. Knott, W. B., and Johnston, C. D. 1969. Insecticide 1410: Evaluation of Acute
LC150A for Bluegill Sunfish. (Unpublished study received Nov 29, 1972 under 361316;
prepared by Woodard Research Corp., submitted by E.I. du Pont de Nemours & Co., Inc.,
Wilmington, Del.; CDL:092249-AA).

SACR :
SACR :

SCV =
SCV =

112


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MRID 66915. Knott, W. B., and Johnston, C. D. 1969. Insecticide 1410: Evaluation of Acute
LC150A for Goldfish. (Unpublished study received Nov 29, 1972 under 3G1316; prepared by
Woodard Research Corp., submitted by E.I. du Pont de Nemours & Co., Inc., Wilmington, Del.;
CDL: 092249-AB).

MRID 66916. Knott, W. B., and Johnston, C. D. 1969. Insecticide 1410: Evaluation of Acute
LC150A for Rainbow Trout. (Unpublished study received Nov 29, 1972 under 3613 16;
prepared by Woodard Research Corp., submitted by E.I. du Pont de Nemours & Co., Inc.,
Wilmington, Del.; CDL:092249-AC).

MRID 94663. Muska, C.F., and Driscoll, R.R. 1982. Early Life Stage Toxicity of Oxamyl to
Fathead Minnow: Haskell Laboratory Report No. 877-81. (Unpublished study received Jan 29,
1982 under 352-372; submitted by E.I. du Pont de Nemours & Co., Inc., Wilmington, Del.;
CDL:246726-D).

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2009. Risks of oxamyl use to federally threatened California red-legged frog (Rana
aurora draytonii). Office of Pesticide Programs. Washington, D.C. February 12, 2009.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

113


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1.2.2 Comparison of Aquatic Life Toxicity Values for Acephate: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
(CWA) (U.S. EPA 2024) are described below. Toxicity data for acephate were gathered by OW
in 2015 and combined with data from OPP's registration review document for acephate (U.S.
EPA 2007).

1.2.2.1 Acephate Acute Toxicity Data

The acephate data include twelve LCsos representing seven species in seven genera that were
classified as "quantitative" data and twenty-six LCsos representing eight species in eight genera
classified as "qualitative" that appear to be acceptable tests given the available information. The
final acute acephate dataset consisted of 45 LCsos for 18 total species across 16 genera, of which
seven were invertebrate species across seven invertebrate genera. Ranked invertebrate GMAVs
from all data sources are listed in Table 2. Acute data for acephate are shown in Table 1.

114


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Table 1. Acute toxicity of acephate to freshwater aquatic organisms.

()\\
MIJR

(iroup'1

(Ionus

Species

IX 50/
IX 50
(Mli/U

S\1 AY

(MS/I-)

(IMAY

Reference

Comment

F

Ephemeridaeb

-

3,136

3,136

3,136

ECOTOX 37219. Hussain et al.
1985

24hr. No species name

F

Pteronarcella

badia

21,200

10,883

10,883

ECOTOX 6797. Mayer and
Ellersieck. 1986



F

Pteronarcella

badia

6,400

ECOTOX 6797. Mayer and
Ellersieck. 1986



F

Pteronarcella

badia

9,500

ECOTOX 6797. Mayer and
Ellersieck. 1986



F

Isogenus

sp.

11,700

11,700

11,700

ECOTOX 6797. Mayer and
Ellersieck. 1986



F

Skwala

sp.

12,000

12,000

12,000

MRID 40094602. Johnson, W. and
M. Finley. 1980



D

Daphnia

magna

71,800

8,927

8,927

MRID 00014565. Wheeler. 1978.



D

Daphnia

magna

1,110

MRID 40098001. McCann 1978

OPP Benchmark value,
75% formulation

E

Gammarus

pseudolimneaus

>50,000

>62,996

>62,996

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

E

Gammarus

pseudolimneaus

>50,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

E

Gammarus

pseudolimneaus

>100,000

Schotteger 1970



F

Chironomus

plumosus

>1,000,000

>135,721

>135,721

Johnson and Finley 1980

No endpoint or duration
reported

F

Chironomus

plumosus

>50,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

48hr EC50

F

Chironomus

plumosus

>50,000

ECOTOX 6797. Mayer and
Ellersieck. 1986



A

Oncorhynchus

mykiss

110,000

530,010

>185,523

ECOTOX 6797. Mayer and
Ellersieck. 1986



A

Oncorhynchus

mykiss

1,100,000

ECOTOX 6797. Mayer and
Ellersieck. 1986



A

Oncorhynchus

mykiss

783,840

ECOTOX 7317. Duangsawasdi.
1977.



115


-------
()\\
MIJR

(iroup'1

(Ionus

Species

IX 50/
IX 50
(MS/1-)

S\1 AY

(IMAY

(MS/'-)

Reference

Comment

A

Oncorhynchus

mykiss

832,000





MRID 40094602. Johnson, W. and
M. Finley. 1980

OPP Benchmark value

A

Oncorhynchus

clarkii

>50,000

>64,940

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

A

Oncorhynchus

clarkii

>60,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

A

Oncorhynchus

clarkii

>100,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

A

Oncorhynchus

clarkii

>50,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

A

Oncorhynchus

clarkii

>100,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

A

Oncorhynchus

clarkii

>50,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

A

Salmo

salar

>50,000

>50,000

>50,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

A

Salmo

salar

>50,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

A

Salmo

salar

>50,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

A

Salmo

salar

>50,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

A

Salmo

salar

>50,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

A

Salmo

salar

>50,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

A

Salmo

salar

>50,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

A

Salmo

salar

>50,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

A

Salvelinus

fontinalis

>50,000

>70,711

>70,711

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

A

Salvelinus

fontinalis

>100,000

MRID 40094602. Johnson, W. and
M. Finley. 1980

Qualitative

B

Lepomis

macrochirus

>50,000

>91,028

>91,028

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

116


-------
()\\
MDR

(iroup'1

(Ionus

Species

IX 50/
IX 50
(MS/1-)

S\1 AY

(IMAY

(MS/'-)

Reference

Comment

B

Lepomis

macrochirus

>1,000,000





ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

B

Lepomis

macrochirus

>50,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

B

Lepomis

macrochirus

>50,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

B

Lepomis

macrochirus

>50,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

B

Ictalurus

punctatus

>1,000,000

>1,000,000

>1,000,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

B

Perca

flavescens

>50,000

>50,000

>50,000

ECOTOX 6797. Mayer and
Ellersieck. 1986

Qualitative

B

Pimephales

promelas

>1,000,000

>1,000,000

>1,000,000

MRID 40094602 Johnson 1980



C

Amby stoma

gracile

8,816,000

8,816,000

8,816,000

Geen 1984



C

Rana

catesbelana

>5,000

>5,000

>179,346

MRID 44042901. Hall & Kolbe.
1980

Qualitative

C

Rana

clamitans

6433000

6,433,000

Lyons et al. 1976

24hr, 90% formulation

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented,
b No species name provided; only Family provided

117


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OPP Acute Benchmark Values

The invertebrate OPP acute benchmark is 550 ng/L, which is V2 of the D. magna LC50 of 1,110
|ig/L cited in U.S. EPA (2007). The fish OPP acute benchmark is 416,000 ng/L, which is V2 of an
O. mykiss LC50 of 832,000 |ig/L cited in U.S. EPA (2007).

GLI Tier II Acute Value Calculation

The acceptable acute dataset for acephate fulfills seven of the eight MDRs, corresponding to the
use of a Secondary Acute Factor (SAF) of 4.3. Applying the SAF to the lowest, most sensitive
GMAV (i.e., 3,136 |ig/L for mayfly (Ephemeridae family)), the calculated Secondary Acute
Value (SAV) is 729.3 |ig/L. The Secondary Maximum Criterion (SMC), which is calculated as
half the SAV, is 364.7 |ig/L. Detailed calculations for the SMC are shown below:

Lowest GMAV

3,136

SAV =	= 729.3 ag/L

4.3

SAV

SMC= —

729.3

SMC = —= 364.7 |xg/L
Genus-Level Invertebrate-only HC05

The genus-level invertebrate acute HC05 following the U.S. EPA (1985) methodology for the
seven invertebrate genera in the acephate dataset (Table 2) was 2,138 |ig/L (Table 3). The second
most sensitive GMAV is for Daphnia and includes the OPP benchmark LC50 of 1,110 ng/L
tested in a 75% formulation. Excluding the OPP acute benchmark LC50 above yields a genus-
level invertebrate HC05 of 2,117 |ig/L, calculated entirely from quantitative data.

Table 2. Acephate invertebrate SMAVs and GMAVs (ng/L).

(Ion us

Species

S\1 AY

GMAV

(iMAY kiink

Chironomus

plumosus

>135,721d

>135,72 ld

7

Gammarus

pseudolimneaus

>62,996°

>62,996°

6

Skwala

sp.

12,000

12,000

5

Isogenus

sp.

11,700

11,700

4

Pteronarcella

badia

10,883

10,883

3

Daphnia

magna

8,927b

8,927b

2

Ephemeridae"

-

3,136

3,136

1

a Family. Species name not reported.

b Geometric mean of quantitative value and OPP invertebrate benchmark value from test with 75% formulation,
c Geometric mean of two qualitative values from U.S. EPA (2015) and third value from U.S. EPA (2007).
d Geometric mean of three values from U.S. EPA (2007).

118


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Table 3. Genus-level invertebrate acute HCos for acephate calculated following the U.S.

N

Rank

GMAV

ln(GMAV)

ln(GMAV)2

P=R/(N+1)

sqrt(P)

1

4

11,700

9.367

87.75

0.5000

0.7071



3

10,833

9.290

86.31

0.3750

0.6124



2

8,927

9.097

82.75

0.2500

0.5000



1

3,136

8.051

64.81

0.1250

0.3536



Sum:



35.81

321.6

1.250

2.173







S2 =

16.12

L =

6.770

A =

7.668

FAV =

2,138

Table 4. Comparison of acute values for acephate.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

Pesticide

OPP Invertebrate
ALB

(lowest LCso/2)
(Year published,
species)

OW GLI Tier
II value (# of
MDRs filled,
magnitude
relative to
ALB)

OW Genus-level
Invertebrate-
only HCos/2
(# of genera,
magnitude
relative to ALB)

Notes

Acephate

550 ng/L
(2007; Daphnia
magna)

364.7 ng/L
(7 MDRs filled,
1.5X)

1,069 ng/L
(7 genera, 0.5 IX)

The FIFRA ALB was based on an acute
toxicity test that used 75% pure acephate
in a wettable powder formulation,
producing an EC50 value of 1,100 |ig/L for
water flea (I). magna). This acute toxicity
test was not used in the GLI Tier II
because the chemical purity was <90%.

Figure 1 shows a genus-level sensitivity distribution for the acephate dataset. Major taxonomic
groups are delineated by different symbols, and invertebrate genera are identified by name. Lines
denoting the OPP acute benchmark values, GLI Tier II calculated value and invertebrate-only
acute HC05/2 are also included.

119


-------
10,000,000

1,000,000

100,000

CUD

H.10,000

01
re

Q. 1,000

01

u

<

100

10

0.0

o
¦

~
~

o

A

Arthropod

Arthropod (Qualitative)
Salrnonid Fish
Salmonid Fish (Qualitative)
Other Fish

Other Fish (Qualitative)
Amphibian

¦	Genus-level arthropod

OPP Invertebrate Benchmark

¦	OPP Fish Benchmark
Tier II Acute Value

~

O — 1=1
Gamma rus

Chironomusb

Daphnia3

• __ • Skwala
^"•Isogenus

O Ephermeridae Pteronarcella
(Family)

Genus-level invertebrate FIC05/2= 1,069 ng/L

OPP Invertebrate Benchmark = 550 ng/L

GLI Tier II = 364.7 ng/L

Notes:

a - Geometric mean of quantitative LC50 and an LC50 for a 70% formulation

used as the invertebrate benchmark value,
b - Listed in OPP benchmark document but not in the Tier II benchmark document,
c - Geometric mean of R. catesbelanaqualitative SMAVand

R. clamitans SMAV representing as the OPP amphibian benchmark,
d - Geometric mean of quantitative SMAV for O. mykiss and

0.1

0.2

0.3

0.4	0.5	0.6

Sensitivity Centile

0.7

0.8

0.9

1.0

Figure 1. Acephate genus-level acute SD.

Symbols represent Genus Mean Acute Values (GMAVs) calculated using all available data from an EPA literature search in 2015,
supplemented the Office of Pesticide Programs (OPP) registration review document for acephate (U.S. EPA 2007).

120


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1.2.2.2 Acephate Chronic Toxicity Data
Chronic Data Sources and Considerations

Chronic toxicity data for acephate were consolidated by OW in 2015 and combined with data
from OPP's registration review document for acephate (U.S. EPA 2007). The final chronic
acephate dataset consisted of one NOECs/LOEC for one invertebrate species (Table 5).

Table 5. C

ironic toxicity data o

'acephate to freshwater aquatic organisms.

OW MDR

Croup'1

(Ion us

Species

NOEC
(MS/1-)

I.OEC
(MS/U

Liulpoinl

Re Terence

Comment

D

Daphnia

magna

150

375.0

Reduction in
offspring

MRID
44466601;
McCain. 1978

Supplemental

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species

(e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Chronic Benchmark Values

The OPP invertebrate chronic benchmark for acephate is 150 |ig/L, which is the NOEC for
Daphnia magna.

The OPP fish chronic benchmark is 5,760 |ig/L, which is the estimated NOEC for Oncorhynchus
mykiss, extrapolated using most sensitive acute 96-h LC50 for rainbow trout (832,000 |ig/L)
divided by 144.44 (highest rainbow trout ACR for organophosphates).

GLI Tier II Chronic Value Calculation

Quantitative chronic tests are not available for acephate. Therefore, per the GLI Tier II
methodology, all three ACRs are the default value of 18, the geometric mean of which (i.e., the
SACR) is 18. The calculated Secondary Chronic Value (SCV) for acephate is 40.52 |ig/L.
Detailed calculations for the SCV are shown below:

SACR = Geometric Mean of the ACRs

SACR = V18 * 18 * 18 = 18

SCV =
SCV =

SACR
729.3
18

= 40.52 [ig/L

121


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Table 6. Summary and comparison of chronic values for acephate.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

Pesticide

OPP Invertebrate

ALB
(NOAEC) (Year
published, species)

OW Tier II value
(# of ACRs filled,
magnitude relative to ALB)

OW Invertebrate-

only HCos
(# of ACRs filled,
magnitude relative
to ALB)

Notes

Acephate

150 ng/L
(2007, Daphnia
magna)

40.52 ng/L

(GLI Tier II; 0 ACRs, 3.7X)

NA

Three default ACRs
of 18 used to derive
GLI Tier II value.

1.2.2.3 Acephate References

ECOTOX 37219. Hussain M.A.; Mohamad R.B.; Oloffs P.C. 1985. Studies on the Toxicity,
Metabolism, and Anticholinesterase Properties of Acephate and Methamidophos. J. Environ. Sci.
Health Part B: Pestic. Food Contam. Agric. Wastes 20(1): 129-147.

ECOTOX 51716. Lyons D.B.; Buckner C.H.; McLeod B.B.; Sundaram K.M.S. 1976. The
Effects of Fenitrothion, Matacil and Orthene on Frog Larvae. Rep. No. CC-X-129, Chemical
Control Research Institute, Department of the Environment Canada, Ottawa, Ontario : 86 p.

ECOTOX 6797. Mayer, F. L. J. and Ellersieck, M. R. 1986. Manual of Acute Toxicity:
Interpretation and Data Base for 410 Chemicals and 66 Species of Freshwater Animals. Resour.
Publ. No. 160, U.S. Department of Interior, Fish and Wildlife Services, Washington, DC 505 p.

ECOTOX 7317. Duangsawasdi, M. 1977. Organophosphate Insecticide Toxicity in Rainbow
Trout (Salmo gairdneri). Effects of Temperature and Investigations on the Sites of Action. Ph.D
Thesis, University of Manitoba, Canada, Ph.D. Thesis, University of Manitoba, Manitoba,
Canada : 138 p.

MRID 00014565. Wheeler, R. E., 1978. 48 Hour Acute Static Toxicity of Orthene (SX911) to
1st Stage Nymph Water Fleas (Daphnia magna Straus). Unpublished study conducted by
Agricultural Research Laboratory, Richmond, California. Sponsored by Chevron Chemical
Company, Ortho Division. Study completed August 25, 1978.

MRID 40094602 Johnson, W. and M. Finley. 1980. Handbook of Acute Toxicity of Chemicals
to Fish and Aquatic Invertebrates: Resource Publication 137. US Fish and Wildlife Service,
Washington, D.C. 106 p.

MRID 40098001 Mayer, F. and M. Ellersieck. 1986 Manual of Acute Toxicity: Interpretation
and Data Base for 410 Chemicals and 66 Species of Freshwater Animals. US Fish & Wildlife
Service, Resource Publication 160. 579 p.

MRID 44042901. Hall, R. J. and E. Kolbe. 1980. Bioconcentration of Organophosphorus
Pesticides to Hazardous Levels by Amphibians. Journal of Toxicology and Environmental
Health 6: 853 -860.

MRID 44466601. McCann, J.A. 1978. U.S. Environmental Protection Agency, Pesticides
Regulation Div., Agricultural Research Center, Animal Biology Laboratory, unpublished report.)

122


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Geen, G.H., B.A. McKeown, T.A. Watson, and D.B. Parker. 1984. Effects of Acephate
(Orthene) on Development and Survival of the Salamander, Ambystoma gracile (Baird). J.
Environ. Sci. Health Part B Pestic. Food Contam. Agric. Wastes, 19, (2), 157-170.

ECOREF#:l 1134

Johnson, W. and M. Finley. 1980. Handbook of Acute Toxicity of Chemicals to Fish and
Aquatic Invertebrates: Resource Publication 137. US Fish and Wildlife Service, Washington,
D C. 106 p.

Mayer, F. L. J. and Ellersieck, M. R. 1986. Manual of Acute Toxicity: Interpretation and Data
Base for 410 Chemicals and 66 Species of Freshwater Animals. Resour. Publ. No. 160, U.S.
Department of Interior, Fish and Wildlife Services, Washington, DC 505 p.Mayer and Ellersiek
1986

Schoettger, R.A., and W.L. Mauck. 1978 . Toxicity of Experimental Forest Insecticides to Fish
and Aquatic Invertebrates. In: D.I.Mount, W.R.Swain, and N.K.Ivanikiw (Eds.), Proceedings of
the First and Second USA-USSR Symposia on the Effects of Pollutants Upon Aquatic
Ecosystems, 11-27.

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2007. Risks of acephate use to the federally-listed California red legged frog (Rana
aurora draytonii). Pesticide effects determination. Office of Pesticide Programs. Washington,
D C. July 19, 2007.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and the Clean Water Act
(CWA). EPA-820-D-24-002.

123


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1.2.3 Comparison of Aquatic Life Toxicity Values for Dimethoate: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
(CWA) (U.S. EPA 2024) are described below. Toxicity data for dimethoate were gathered by
OW in 2015 and combined with data from OPP's registration review document for dimethoate
(U.S. EPA 2008).

1.2.3.1 Dimethoate Acute Toxicity Data

The dimethoate acute data include six LCsos representing five species in five genera that were
classified as "quantitative" data, two 96-hour LCsos for the species Poecilia reticulata classified
as "qualitative" that appear to be acceptable tests given the available information; and two
"qualitative" 48-hour LCsos for species within the genus Chironomus included in order to
calculate an invertebrate-only HCos.

The final acute dimethoate dataset consisted of eight quantitative LCsos and two "qualitative"
LCsos for eight total species across seven genera, of which five were invertebrate species across
four invertebrate genera. Acute data for dimethoate are shown in Table 1. Ranked invertebrate
GMAVs (both quantitative and qualitative) are listed in Table 2.

Table 1. Acceptable acute toxicity t

ata of dimethoate to freshwater aquatic organisms

OW
M l)K

(1 rou p1'

(Ion us

Species

l.( 50/
IX 50
(Mii/U

S\1 AY

(MS/1->

(IMAY

(MS/'-)

Reference

Comment

F

Chironomus

riparius

481

481

345.4

ECOTOX 102849.
Domingues et al.
2007

Duration, 48hr

F

Chironomus

dilutus

248

248

ECOTOX 74947.
Anderson and Zhu
2004

Duration, 48hr

D

Daphnia

magna

3,154

3,154

3,154

ECOTOX 18476.
Song et al. 1997

Represents 8
tests

F

Pteronarcys

californica

43

43

43

MRID 00003503.
Johnson and Finley.
1980

Represents 3
tests

E

Gammarus

lacustris

200

200

200

ECOTOX 6797.
Mayer and Ellersieck
1986

Represents 2
tests

B

Poecilia

reticulata

548,800

429,798

429,798

ECOTOX 5180.
Canton etal. 1980

OECD test-
not publicly
available

B

Poecilia

reticulata

336,600

ECOTOX 5370.
Maas 1982

OECD test-
not publicly
available

B

Lepomis

macrochirus

6,000

6,000

6,000

ECOTOX 6797.
Mayer and Ellersieck
1986

Represents 2
tests

A

Oncorhynchus

mykiss

8,600

7,302

7,302

ECOTOX 6797.
Mayer and Ellersieck
1986



124


-------
o\\

MDR

Croup'

(Ion us

Species

I X 50/
I X 50

(Mli/I.)

S\1 AY

(MS/'-)

GMAV
(MS/'-)

Reference

Comment

A

Oncorhynchus

mykiss

6,200





ECOTOX 6797.
Mayer and Ellersieck
1986

Represents 7
tests

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important
warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Acute Benchmark Values

The OPP invertebrate acute benchmark is 21.5 |ig/L, which is V2 of the Pteronarcys californica
LC50 of 43 |ig/L cited in U.S. EPA (2008).

The OPP fish acute benchmark is 3,100 |ig/L, which is V2 of the Oncorhynchus mykiss LC50 of
6,200 |ig/L cited in U.S. EPA (2008).

GLI Tier II Acute Value Calculation

The acceptable dataset for dimethoate represents five of the eight MDRs, corresponding to the
use of a SAF of 6.1. Applying the SAF to the lowest, most sensitive GMAV (i.e., 43.0 |ig/L for
stonefly (Pteronarcys californica)), the calculated SAV is 7.0 |ig/L. Half of the SAV is 3.5 |ig/L
The SMC of 3.5 |ig/L is lower than the most sensitive GMAV. Detailed calculations are shown
below:

Lowest GMAV

SAV =	—	

SAF

43.0

SAV = — = 7.0 \ig/L
SAV

SMC = ——

7.0

SMC = — = 3.5 |xg/L

Genus-Level Invertebrate-Only HC05

The genus-level invertebrate-only acute HC05 following the U.S. EPA (1985) methodology for
the four invertebrate genera in the dimethoate dataset (Table 2) was 4.296 |ig/L (Table 3).

125


-------
Table 2. Dimethoate invertebrate SMAVs and GMAVs (iig/L).

(Ion us

Species

SM AY

(IMAY

(iMAY Kiink

Daphnia

magna

3,154

3154

4

Chironomus

riparius

481.0*

345.4

3

Chironomus

dilutus

248.0*

Gammarus

lacustris

200.0

200.0

2

Pteronarcys

californica

43.00

43.00

1

* Qualitative values (48-hour LCsos).

Note: SMAVs and GMAVs for Chironomus sp. are 48-hour tests that were classified as qualitative in but
are added here to meet minimum requirements to calculate a genus-level invertebrate HC05.

Table 3. Genus-level invertebrate acute HC05 for dimethoate calculated following the U.S.
EPA (1985) methodology.

N

Rank

GMAV

ln(GMAV)

ln(GMAV)2

P=R/(N+1)

sqrt(P)

4

4

3154

8.056

64.906

0.8000

0.8944



3

345.4

5.845

34.161

0.6000

0.7746



2

200.0

5.298

28.072

0.4000

0.6325



1

43.00

3.761

14.147

0.2000

0.4472



Sum:



22.96

141.3

2.000

2.749







S2 =

85.34

L =

-0.608

A =

1.458

hc05 =

4.296

126


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Table 4. Summary and comparison of acute values for dimethoate.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio >1 indicates the OPP value is higher than the OW value.	

Pesticide

OPP

Invertebrate

ALB
(lowest LCso/2)
(Year published,
species)

OW GLI Tier
II values(# of
MDRs filled,
magnitude
relative to
ALB)

OW Genus-level
Invertebrate-
only HCos/2
(# of genera,
magnitude
relative to ALB)

Notes

Dimethoate

21.5 ng/L
(2016;

Pteronarcys
californica)

3.5 ng/L
(5 MDRs filled,
6. IX)

2.15 ng/L
(4 genera*, 10X)

The FIFRA ALB is half the LC50 reported for
stonefly (P. californica), which was used as
the basis for the GLI Tier II acute value.
The genus-level invertebrate value is lower
than the FIFRA ALB because of the relatively
steep slope and small sample size calculated
from the Guidelines algorithm, while the
FIFRA ALB is half of the most sensitive
GMAV.

* GMAV for Chironomus sp. is based on data
classified as qualitative that were included to
allow for sufficient sample size to calculate a
genus-level invertebrate value. Tests were
classified as qualitative because it was for a
non-standard duration (48-hours).

Figure 1 shows a genus-level sensitivity distribution for the dimethoate dataset. Major taxonomic
groups are delineated by different symbols, and invertebrate genera are identified by name. Lines
denoting the OPP acute benchmark values, GLI tier II calculated acute value, and invertebrate-
only acute HC05/2 are included.

127


-------
1,000,000

100,000

10,000

—I

tJJO

3;

01

ro 1,000
o

-C


-------
1.2.3.2 Dimethoate Chronic Toxicity Data
Chronic Data Sources and Considerations

Chronic toxicity data for dimethoate were consolidated by OW in 2015 and combined with data
from OPP's registration review document for dimethoate (U.S. EPA 2008). The final chronic
dimethoate dataset consisted of two NOECs/LOECS for two species across two genera, of which
one was an invertebrate and one was a vertebrate (Table 5).

Table 5. Chronic toxicity data of dimethoate to freshwater aquatic organisms

OW
MI)R

(il'OII|):l

(Ion us

Species

\()IX

(jig/U

LOIX
(MS/'-)

Knclpoinl

Reference

Comment

D

Daphnia

magna

40

100

Reproduction,
survival and growth

MRID 42864701

Quantitative

A

Oncorhynchus

mykiss

430

840

Impaired growth

MRID 43106301,

43106302,

43106303

Quantitative

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species

(e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Chronic Benchmark Values

The OPP invertebrate chronic benchmark is 0.5 |ig/L, which is the estimated NOEC for
Pteronarcys californica using the ACR for D. magna. P. California LC50 (43 |ig/L) ^ I), magna
ACR (83) = 0.5 |ig/L.

The OPP fish chronic benchmark is 430 |ig/L, which is the NOEC for Oncorhynchus mykiss.
GLI Tier II Chronic Value Calculation

Quantitative dimethoate chronic and acute toxicity data were available for water flea (Daphnia
magna) and rainbow trout (Oncorhynchus mykiss), allowing for the calculation of two ACRs.
The default value of 18 was used to fulfill the third ACR per the GLI Tier II methodology. ACRs
were calculated using the test with the lowest acute endpoint. The rainbow trout (Oncorhynchus
mykiss) test with the lowest acute endpoint (i.e., 6,200 |ig/L) was therefore used in the
calculations.

The acute and chronic tests for water flea (Daphnia magna) and for rainbow trout
(iOncorhynchus mykiss) were conducted in different laboratories, using water of different
physical characteristics; therefore, the ACRs were calculated using the OPP methodology, which
involves using the NOAEC as the chronic value. The calculated SCV is 0.3 |ig/L. Detailed
calculations for the SCV are shown below:

129


-------
SACR = Geometric Mean of the ACRs
SACR = Vl4.4#79#18 = 27.4

SCV =

SACR

SCV = ^ = 0.3 \ig/L

Table 6. Summary and comparison of chronic values for dimethoate.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for

each value comparison. A ratio >1 indicates the OPP va

ue is higher than t

ie OW value.

Pesticide

OPP Invertebrate

ALB
(NOAEC) (Year
published, species)

OW Tier II

value
(# of ACRs
filled, magnitude
relative to ALB)

OW Invertebrate-

only HCos
(# of ACRs filled,

magnitude
relative to ALB)

Notes

Dimethoate

0.5 ng/L
(2016, estimated
NOAEC value for

Pteronarcys
californica calculated
using the ACR for
Daphnia magna)

0.3 ng/L
(GLI Tier II; 2
ACRs, 1.7X)

NA

One default ACR of 18
used to derive GLI Tier II
value.

1.2.3.3 Dimethoate References

ECOTOX 102849. Domingues, I., Guilhermino, L., Soares, A. M. V. M., and Nogueira, A. J.A.
2007. Assessing Dimethoate Contamination in Temperate and Tropical Climates: Potential Use
of Biomarkers in Bioassays with Two Chironomid Species. Chemosphere 69(1): 145-154.

ECOTOX 18476. Song, M. Y., Stark, J. D., and Brown, J. J. 1997. Comparative Toxicity of Four
Insecticides, Including Imidacloprid and Tebufenozide, to Four Aquatic Arthropods. Environ.
Toxicol. Chem. 16(12): 2494-2500.

ECOTOX 5180. Canton, J. H., Wegman, R. C. C., Van Oers, A., Tammer, A. H. M., Mathijssen-
Spiekman, E. A. M., and Van den Broek, H. H. 1980. Environmental Toxicological Research
with Dimethoate and Omethoate, Rep.No. 121/80, Natl. Inst. Public Health Environ. Hyg.: 6 p.

ECOTOX 5370. Maas, J.L. 1982. Toxicity of Pesticides. Rep.No.82, Lab.for Ecotoxicol., Inst.for
Inland Water Manag.and Waste Water Treatment 15: 4 p.

ECOTOX 6797. Mayer, F. L., and Ellersieck, M. R. 1986. Manual of Acute Toxicity:
Interpretation and Data Base for 410 Chemicals and 66 Species of Freshwater Animals.
Resour.Publ.No.160, U.S.Dep.Interior, Fish Wildl.Serv., Washington, DC : 505 p.

ECOTOX 74947. Anderson, T. D., and Zhu, K. Y. 2004. Synergistic and Antagonistic Effects of
Atrazine on the Toxicity of Organophosphorodithioate and Organophosphorothioate Insecticides
to Chironomus tentans (Diptera: Chironomidae). Pestic. Biochem. Physiol. 80(1): 54-64.

130


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MRID 00003503. Johnson, W. and M. Finley. 1980. Handbook of Acute Toxicity of Chemicals
to Fish and Aquatic Invertebrates: Resource Publication 137. US Fish and Wildlife Service,
Washington, D.C. 106 p.

MRID 42864701. Wuthrich, V. 1990. Influence of Dimethoate on the Reproduction of Daphnia
magna. Unpublished study conducted by RCC UMWELTCHEMIE AG, Itingen, Switzerland.
Study number 264464. Sponsored by Dimethoate Task Force, Ingelheim, Germany and
submitted by Cheminova Agro A/S, Harbonone-Lenmark, DK. Study completed December 20,
1990.

MRID 43106301 Strawn, T. and M. Muckerman. 1994. Early Life-stage Toxicity of Dimethoate
to the Rainbow Trout (Oncorhynchus mykiss) Under Flow-through Conditions: Final Report:
Lab Project Number: 40864. Unpublished study prepared by ABC Labs, Inc. 436.

MRID 43106302 Strawn, T. L., and M. Muckerman. 1994. Early Life-Stage Toxicity of
Dimethoate to the Rainbow Trout (Oncorhynchus mykiss) under Flow-Through Conditions.
Unpublished study conducted by ABC Laboratories, Inc., Columbia, Missouri. Report No
40864R. Sponsored by Cheminova Agro A/S, Lemvig, Denmark. Study submitted January 25,
1994.

MRID 43106303 Mahalik, R. and J. B Bussard. 1993. Method Validation for the Analysis of
Dimethoate in Aquatic Test Water. Unpublished study conducted by ABC Laboratories, Inc.,
Columbia, Missouri. Report No. 40863. Sponsored by Cheminova Agro A/S, Lemvig,
Denmark. Study submitted July 21, 1993.

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,

C.E.,	D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2008. Risks of dimethoate use to the federally-listed California red legged frog (Rana
aurora draytonii). Pesticide effects determination. Office of Pesticide Programs. Washington,

D.C.	January 31, 2008.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and the Clean Water Act
(CWA). EPA-820-D-24-002.

131


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1.2.4 Comparison of Aquatic Life Toxicity Values for Phosmet: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
(CWA) (U.S. EPA 2024) are described below. Toxicity data for phosmet were gathered by OW
in 2015 and combined with data from OPP's registration review document for phosmet (U.S.
EPA 2009).

1.2.4.1 Phosmet Acute Toxicity Data

Acute data for phosmet include thirty-four LCsos representing ten species in eight genera that
were classified as "quantitative" data and one 48-hour LCso for the fairy shrimp Streptocephalus
sealii classified as qualitative, but included here to increase the number of invertebrate genera to
four, thereby allowing the calculation of an invertebrate genus-level HCos. This test was
classified as qualitative because it was for a non-standard duration (48-hours).

The final acute phosmet dataset consisted of 35 LCsos for 11 species across nine genera, of
which four were invertebrate species representing four different genera. Acute data for phosmet
are shown in Table 1. The ranked invertebrate GMAVs are listed in Table 2.

Table 1. Acute toxicity data of phosmet to freshwater aquatic organisms.

OW
MI)R

(iroup'1

(ionus

Species

l .( 50/
IX 50
(Mli/U

S\1 AY

(MS/'-)

(IMAY

(MS/'-)

Reference

D

Streptocephalus

sealii

170

170.0

170.0

MRID 40094602

D

Daphnia

magna

5.6

5.6

5.6

Mayer and Ellersieck 1986

E

Gammarus

fasciatus

2.4

2.4

2.4

MRID 00063193; Sanders 1972

E

Caecidotea

brevicauda

72





Mayer and Ellersieck 1986

E

Caecidotea

brevicauda

90

80.50

80.50

Mayer and Ellersieck 1986

B

Pimephales

promelas

7,300

7,300

7,300

Mayer and Ellersieck 1986

B

Lepomis

macrochirus

1,000





Mayer and Ellersieck 1986

B

Lepomis

macrochirus

1,400





Mayer and Ellersieck 1986

B

Lepomis

macrochirus

1,000





Mayer and Ellersieck 1986

B

Lepomis

macrochirus

640





Mayer and Ellersieck 1986

B

Lepomis

macrochirus

200





Mayer and Ellersieck 1986

B

Lepomis

macrochirus

22





Mayer and Ellersieck 1986

B

Lepomis

macrochirus

60





Mayer and Ellersieck 1986

B

Lepomis

macrochirus

70





Mayer and Ellersieck 1986

B

Lepomis

macrochirus

180





Mayer and Ellersieck 1986

B

Lepomis

macrochirus

560





Mayer and Ellersieck 1986

B

Lepomis

macrochirus

200





Mayer and Ellersieck 1986

B

Lepomis

macrochirus

70

231.2

231.2

MRID 00063194; Julinand
Sanders 1977

B

Micropterus

dolomieu

150.0

150.0

-

Mayer and Ellersieck 1986

B

Micropterus

salmoides

160.0

160.0

154.9

Mayer and Ellersieck 1986

A

Oncorhynchus

tshawytscha

150.0

150.0

-

Mayer and Ellersieck 1986

132


-------
()\\
MDR

(iioup1

(ionus

Species

IX 50/
I X 50
(Mii/U

S\1 AY

(MB/'-)

(IMAY

(MB/'-)

Reference

A

Oncorhynchus

mykiss

280.0





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

1,200





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

1,600





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

420.0





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

130.0





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

105.0





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

480.0





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

240.0





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

560.0





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

120.0





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

300.0





Mayer and Ellersieck 1986

A

Oncorhynchus

mykiss

513.9

352.5

229.9

Julin and Sanders 1977

B

Ictalurus

punctatus

10,600





Mayer and Ellersieck 1986

B

Ictalurus

punctatus

11,000

10,798

10,798

MRID 00063194; Julin and
Sanders 1977

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important

warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Benchmark Acute Values

The OPP invertebrate acute benchmark is 4.32 |ig/L, which is V2 of the Daphnia magna EC50 of
8.64 |ig/L.

The OPP fish acute benchmark is 35 |ig/L, which is V2 of the Lepomis macrochirus LC50 of 70
Hg/L.

GLI Tier II Acute Value Calculation

The acceptable dataset for phosmet represents five of the eight MDRs, corresponding to the use
of an SAF of 6.1. Applying the SAF to the lowest, most sensitive GMAV (i.e., 2.4 |ig/L for scud
(Gammarus fasciatus)), yields the SAV of 0.39 |ig/L. Half of the SAV is 0.20 |ig/L. The SMC of
0.20 |ig/L. Detailed calculations for the SMC are shown below:

Lowest GMAV

2.4

SAV = — = 0.39 ag/L
6.1

133


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SMC =

SAV
~2~
0.39

SMC = —- = 0.20|ig/L

Genus-Level Invertebrate-only HCos

The genus-level invertebrate-only acute HCos calculated following the U.S. EPA (1985)
methodology for the four invertebrate genera in the phosmet dataset (Table 2) is 0.1480 |ig/L
(Table 3).

Table 2. Phosmet invert

tebrate SMAVs and GMAVs (jug/L).

(iI'll IIS

Species

SM AY

(;ma\

CMAY R;tilk

Strep to cephalus

sealii

170.0

170.0

4

Caecidotea

brevicauda

80.50

80.50

3

Daphnia

magna

5.600

5.600

2

Gammarus

fasciatus

2.400

2.400

1

Note: The S. sealii GMAV is based on data classified as qualitative that were included to allow for a sufficient
sample size to calculate an invertebrate genus-level HCos.

Table 3. Genus-level invertebrate acute HCos for phosmet calculated following the U.S.

N

Rank

GMAV

ln(GMAV)

ln(GMAV)2

P=R/(N+1)

sqrt(P)

4

4

170

5.136

26.38

0.8000

0.8944



3

80.50

4.388

19.26

0.6000

0.7746



2

5.6

1.723

2.968

0.4000

0.6325



1

2.4

0.8755

0.7664

0.2000

0.4472



Sum:



12.12

49.37

2.000

2.749







S2 =

113.6

L =

-4.294

A =

-1.910

hc05 =

0.1480

Note: The fourth most sensitive GMAV was classified as qualitative for the reason explained under Data Sources
and Considerations.

134


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Table 4. Summary and comparison of acute values for phosmet.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

ratio >1 inc

icates the OPP value is higher than the OW value.

Pesticide

OPP

Invertebrate

ALB
(lowest LCso/2)
(Year published,
species)

OPP GLI Tier II

values (# of
MDRs filled,
magnitude
relative to ALB)

OW Genus-

level
Invertebrate-
only HCos/2
(# of genera,
magnitude
relative to ALB)

Notes

Phosmet

4.32 ng/L
(2023; Daphnia
magna)

0.20 ng/L
(5 MDRs filled,

22X)

0.074 (ig/L
(4 genera*, 58X)

The FIFRA ALB is based on an acute
toxicity test that used 51% TEP, producing
an EC50 value of 8.64 |ig/L for water flea (I),
magna). This acute toxicity test was not used
in the GLI Tier II or genus-level invertebrate
value calculations as per the Guidelines.

The genus-level invertebrate value is lower
than the FIFRA ALB because the most
sensitive SMAV is an EC50 of 2.4 |ig/L for
scud (G. fasciatus). This study was not used
to derive the FIFRA ALB because it was
categorized as "qualitative" as the raw data
was not available.

* GMAV for the spiny-tail fairy shrimp
Streptocephalus sealii is based on data
classified as qualitative that were included to
allow for sufficient sample size to calculate a
genus-level invertebrate value. The test was
classified as qualitative because it was for a
non-standard duration (48-hours).

Figure 1 shows a genus-level sensitivity distribution for the phosmet dataset. Major taxonomic
groups are delineated by different symbols, and invertebrate genera are identified by name. Lines
denoting the OPP benchmark acute values, the GLI Tier II calculated value, and invertebrate-
only acute HC05/2 are included.

135


-------
100,000.00

10,000.00

1,000.00 -

M 100.00

a;

E

O 10.00

1.00

0.10

0.01

•	Arthropod

O Arthropod (Qualitative)
¦ Salmonid Fish

~	Other Fish
	GLI Tier II Value

	Genus-level Invertebrate HC05/2

	 OPP Invertebrate Benchmark

— • • OPP Fish Benchmark

• Caecidotea

Streptocepahlus

Daphn.ia	

OPP Fish Benchmark = 35 |ig/L

OPP Invertebrate Benchmark = 4.32 |ig/L

• Gammarus

GLI Tier II Acute Value = 0.20 |ig/L
Genus-level Invertebrate FIC05/2 = 0.0740 ng/L

0.0

0.1

0.2

0.3

0.4	0.5	0.6

Sensitivity Centile

0.7

0.8

0.9

1.0

Figure 1. Phosmet genus-level SD.

Symbols represent Genus Mean Acute Values (GMAVs) calculated using all available data from an EPA literature search in 2015,
supplemented the Office of Pesticide Programs (OPP) registration review document for phosmet (U.S. EPA 2009).

136


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1.2.4.2 Phosmet Chronic Toxicity Data
Chronic Data Sources and Considerations

Chronic toxicity data for phosmet were gathered from by OW in 2015 for phosmet and combined
with data from OPP's registration review document for phosmet (U.S. EPA 2009). The final
chronic phosmet dataset consisted of four NOECs/LOECS for four species across four genera.
One test was an invertebrate genus and three were vertebrate genera (Table 5).

Table 5. Chronic toxicity data of phosmet to freshwater aquatic organisms

OW
MI)R

(il'OII|):l

(Ion us

Species

\oi:c
(MU/I)

LOW
(MS/'-)

Liulpoinl

Reference

Comment

D

Daphnia

magna

0.75

1.0

Reduced number of
offspring

MRID 40652801;
Burgess. 1988

Quantitative

A

Oncorhynchus

mykiss

3.2

6.1

Reduction in growth

MRID 40938701;
Cohle. 1988

Quantitative

B

Pimephales

promelas

1.0

9.3

Survival and
fertilization success

MRID 48673002;
York. 2012

Acceptable

C

Xenopus

laevis

8.1

9.6

Metamorphosis

MRID 48673001;
Lee. 2012

Acceptable

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species

(e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Chronic Benchmark Values

The OPP invertebrate chronic benchmark is 0.75 |ig/L, which is the NOEC for Daphnia magna.
The OPP fish chronic benchmark is 1.0 |ig/L, which is the NOEC for Pimephalespromelas.

GLI Tier II Chronic Value Calculation

Quantitative phosmet chronic and acute toxicity data were available for rainbow trout
{Oncorhynchus mykiss) and water flea (Daphnia magna), allowing for the calculation of two
ACRs. The default value of 18 was used to fulfill the third ACR per the GLI Tier II
methodology. The quantitative acute and chronic tests for the water flea (Daphnia magna) and
rainbow trout (Oncorhynchus mykiss) were conducted in different laboratories, using water of
different physical characteristics; therefore the ACRs were calculated using the OPP
methodology, which involves using the NOAECs as the chronic values. Detailed calculations for
the SCV, which was calculated as 0.02 |ig/L, are shown below:

SACR = Geometric Mean of the ACRs
SACR = a/7 * 32.8 * 18 = 16.0

137


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SCV =	

SACR

0.39

SCV = — = 0.02 [ig/L

Table 6. Comparison of chronic values for phosmet.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio >1 indicates the OPP value is higher than the OW value.	

Pesticide

OPP Invertebrate

ALB
(NOAEC) (Year
published, species)

OW Tier II value
(# of ACRs filled,

magnitude
relative to ALB)

OW Invertebrate-

only HCos
(# of ACRs filled,

magnitude
relative to ALB)

Notes

Phosmet

0.75 ng/L
(2023, Daphnia
magna)

0.02 ng/L
(GLI Tier II; 2
ACRs, 38X)

NA

One default ACR of 18
used to derive GLI Tier II
value.

1.2.4.3 Phosmet References

ECOTOX 6797. Mayer, F. L. J., and Ellersieck, M. R. 1986. Manual of Acute Toxicity:
Interpretation and Data Base for 410 Chemicals and 66 Species of Freshwater Animals. Resour.
Publ. No. 160, U.S. Department of Interior, Fish and Wildlife Services, Washington, DC 505 p.

MRID 00063193. Sanders, H.O. 1972. Toxicity of some insecticides to four species of
Malacostracan crustaceans. U.S. Fish and Wildlife Service, Fish-Pesticide Research Laboratory.
Washington, D.C.: USFWS. Technical papers of the Bureau of Sport Fisheries and Wildlife 66;
published study; CDL:232666-T.

MRID 00063194 and ECOTOX 857. Julin, A. M., and Sanders, H.O. 1977. Toxicity and
accumulation of the insecticide imidan in freshwater invertebrates and fishes. Transactions of the
American Fisheries Society. 106(4):386-392.

MRID 40652801. Burgess, D. 1988. Chronic toxicity of 14C-Imidan to Daphnia magna under
flow-through test conditions. Analytical bio-chemistry laboratories, Inc.; Report No. 35778.
(Unpublished report received August 10, 1988; submitted by ICI Americas, Inc. under EPA
Accession No. 406528-01).

MRID 40938701. Cohle, P. 1988. Early life stage toxicity of C14-Phosmet to rainbow trout
(Salmo gairdneri), in a flow through system. Prepared by ABC Laboratories, Inc. Columbia,
MO. Submitted by ICI Agrochemicals, England.

MRID 48673001. Lee, M. 2012. Phosmet - Amphibian Metamorphosis Assay with African
Clawed Frog (Xenopus laevis). Project Number: 12791/6142. Unpublished study prepared by
Smithers Viscient Laboratories. 127 p. Relates to L0001444.

MRID 48673002. York, D. 2012. Phosmet - Short-Term Reproduction Assay with Fathead
Minnow (Pimephales promelas). Project Number: 12791/6143. Unpublished study prepared by
Smithers Viscient Laboratories. 161 p. Relates to L0001444.

138


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U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2009. Problem formulation for the environmental fate and ecological risk, endangered
species, and drinking water assessments in support of the registration review of phosmet. Office
of Pesticide Programs. Washington, D.C. April 16, 2009.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and the Clean Water Act
(CWA). EPA-820-D-24-002

139


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1.2.5 Comparison of Aquatic Life Toxicity Values for Terbufos: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
(CWA) (U.S. EPA 2024) for terbufos are described below. Toxicity data for terbufos were
gathered by OW in 2015 and combined with data from OPP's registration review document for
terbufos (U.S. EPA 2015).

1.2.5.1 Terbufos Acute Toxicity Data

The final acute terbufos dataset consisted of 33 LCsos for nine species representing nine genera,
of which five were invertebrate species representing five invertebrate genera. Acute data for
terbufos are shown in Table 1. The invertebrate GMAVs are listed in Table 2.

140


-------
Table 1. Acute toxicity data of terbufos to freshwa

er aquatic organisms.

()\\
MI)R

(iroup'1

(Ion us

Species

LC50/
IX 50

(MU/I-)

S\1 AY

(MJi/l)

(IMAY

(MS/'-)

Reference

Comment

D

Ceriodaphnia

dubia

0.139

0.1286

0.1286

ECOTOX 153854. Choung et al. 2011

Quantitative, >98% a.i.

D

Ceriodaphnia

dubia

0.119

ECOTOX 153854. Choung et al. 2012

Quantitative, >98% a.i.

E

Daphnia

magna

0.400

0.2608

0.2608

ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

E

Daphnia

magna

0.170

MRID 00101495



E

Gammarus

pseudolimnaeus

0.200

0.2000

0.2000

ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

E

Procambaras

clarkii

5.782

6.801

6.801

ECOTOX 18475. Fornstrom et al. 1997

Qualitative, control mortality;
organisms fed during experiment

E

Procambaras

clarkii

8.0

MRID 00085176



F

Chironomus

plumosus

1.4

1.400

1.400

ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

A

Oncorhynchus

mykiss

10.00





ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

A

Oncorhynchus

mykiss

13.00





ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

A

Oncorhynchus

mykiss

7.600





ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

A

Oncorhynchus

mykiss

8.400





ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

A

Oncorhynchus

mykiss

10.00

10.45

10.45

ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

A

Oncorhynchus

mykiss

13.20





ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

A

Oncorhynchus

mykiss

15.30





ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

A

Oncorhynchus

mykiss

8.600





ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

A

Oncorhynchus

mykiss

11.50





ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

141


-------
()\\
MDR

(i rou |):|

(Ion us

Species

IX 50/
IX 50
(Mli/I )

S\1 AY

(M8/U

(IMAY

(M8/I-)

Reference

('omnicnl

A

Oncorhynchus

mykiss

9.400





MRID 00037483. Sleight. 1972

Quantitative, 86.3% a.i.

A

Salmo

trutta

20

20.00

20.00

MRID 00087718



B

Pimephales

promelas

12.870

70.85

70.85

ECOTOX 14097. Call et al. 1989

Qualitative, Source of test
species unknown; dechlorinated
tap water used; no replicate

B

Pimephales

promelas

390.0





ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

C

Lepomis

macrochirus

1.700





ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

C

Lepomis

macrochirus

2.400





ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

C

Lepomis

macrochirus

2.000





ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

C

Lepomis

macrochirus

1.600





ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

C

Lepomis

macrochirus

1.500





ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

C

Lepomis

macrochirus

1.800

1.569

1.569

ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

C

Lepomis

macrochirus

1.500

ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

C

Lepomis

macrochirus

1.500





ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

C

Lepomis

macrochirus

1.100





ECOTOX 6797. Mayer and Ellersieck.
1986

Quantitative, 88% a.i.

C

Lepomis

macrochirus

0.770





MRID 00087718. Roberts and Wineholt.
1976

Quantitative, 86% a.i.

C

Lepomis

macrochirus

3.80





MRID 00037483



C

Lepomis

macrochirus

0.87





MRID 00085176



a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species (e.g., bluegill, channel catfish,
etc.)

142


-------
C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

143


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OPP Benchmark Acute Values

The OPP invertebrate acute benchmark is 0.085 |ig/L, which is V2 of the Daphnia magna acute
test value of 0.17 |ig/L.

The OPP fish acute benchmark is 0.385 |ig/L, which is V2 of the Lepomis macrochirus acute LC50
of 0.770 |ig/L.

GLI Tier II Acute Value Calculation

The Method B acute dataset for terbufos fulfills five of the eight MDRs, corresponding to the use
of a Secondary Acute Factor (SAF) of 6.1. Applying the SAF to the lowest, most sensitive
GMAV (i.e., 0.128 |ig/L for water flea (Ceriodaphnia dubia)), yields the calculated Secondary
Acute Value (SAV) of 0.021 |ig/L. The Secondary Maximum Criterion (SMC), which is
calculated as half the SAV, is 0.011 |ig/L.

Detailed calculations for the SMC are shown below:

Lowest GMAV

0.128

SAV = —— = 0.021 ag/L
6.1

SAV

SMC= —

0.021

SMC = —= 0.0111xg/L

Genus-Level Invertebrate-only Acute HC05

The genus-level invertebrate-only acute HC05 calculated following the U.S. EPA (1985)
methodology for the five invertebrate genera (Table 2) in the terbufos dataset is 0.0283 ng/L
(Table 3).

Table 2. Terbufos invcrlebrale SMAV and GMAV (iig/I.).

(Ion us

Species

SMAV

GMAV

GMAV kit 11k

Procambarus

clarkii

6.801

6.801

5

Chironomus

plumosus

1.400

1.400

4

Daphnia

magna

0.2608

0.2608

3

Gammarus

pseudolimnaeus

0.2000

0.2000

2

Ceriodaphnia

dubia

0.1268

0.1268

1

Note: The Procambarus clarkii SMAV and GMAV is the geometric mean of a qualitative LC50 used to fill an MDR
group and an acceptable LC50 listed in the OPP registration review document.

144


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Table 3. Genus-level invertebrate-only acute HCos for terbufos calculated following the

N

Rank

(.MAY

ln(GMAV)

ln(GMAV)2

P=R/(N+1)

s qrt(P)

5

4

1.400

0.336

0.11

0.6667

0.8165



3

0.2608

-1.344

1.81

0.5000

0.7071



2

0.2000

-1.609

2.59

0.3333

0.5774



1

0.1286

-2.051

4.206

0.1667

0.4082



Sum:



-4.67

8.72

1.6667

2.5092







S2 =

35.285

L =

-4.893

A =

-3.565

hc05 =

0.0283

Table 4. Comparison of acute values for terbufos.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

ratio >1 indicates the OPP value is higher t

ian the OW value.



OPP Invertebrate ALB

OPP GLI Tier II value (#
of MDRs filled,
magnitude relative to
ALB)

OW Genus-level
Invertebrate-only HCos/2
(# of genera, magnitude
relative to ALB)

Pesticide

(lowest LCso/2) (Year
published, species)

Terbufos

0.085 ng/L

(2023; Daphnia magna)

0.011 ng/L
(5 MDRs filled, 1 .IX)

0.014 (ig/L
(4 genera, 6. IX)

Figure 1 shows a genus-level sensitivity distribution for the terbufos dataset. Major taxonomic
groups are delineated by different symbols, and invertebrate genera are identified by name. Lines
denoting the OPP acute benchmark values, GLI Tier II calculated acute value and invertebrate-
only acute HC05/2 are included.

145


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1,000.000

100.000

10.000

tuo
3

SA

£
3
-Q

1—

.01

1.000

0.100

0.010

0.001

•

Arthropod

o

Arthropod (Qualitative)

¦

Salmonid Fish

~

Other Fish



Genus-level Invertebrate



OPP Invert. Benchmark

	

OPP Fish Benchmark

	

GLI Tier II (Method B)

Gammarus •



Ceriodaphnia

0.0

0.1

0.2

Chironomus

Daphnia

Procambarus o

OPP Fish Benchmark = 0.385 ng/L

OPP Invertebrate Benchmark = 0.085 ^ig/L

Genus-level Invertebrate HC05/2 = 0..0141 ur/L

GLI Tier II Acute Value = 0.011 pg/L

0.3

0.4	0.5	0.6

Sensitivity Centile

0.7

0.8

0.9

1.0

Figure 1. Terbufos genus-level acute SD.

Symbols represent Genus Mean Acute Values (GMAVs) calculated using all available data from an EPA literature search in 2015,
supplemented the Office of Pesticide Programs (OPP) registration review document for terbufos (U.S. EPA 2015).

146


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1.2.5.2 Terbufos Chronic Toxicity Data
Chronic Data Sources and Considerations

Chronic toxicity data for terbufos were gathered by OW in 2015 for terbufos and combined with
data from OPP's registration review document for terbufos (U.S. EPA 2015). The final chronic
terbufos dataset consisted of two NOECs/LOECS for two species across two genera, of which
one was an invertebrate and one was a vertebrate (Table 5).

Table 5. Chronic toxicity data of terbufos to freshwater aquatic organisms.

OW
MIJR

(iioup'

(Ion us

Species

\oi:c

(Mii/U

LOIX

(MS/'-)

Knilpoinl

Reference

D

Daphnia

magna

0.030

0.076

Reductions in length
and number of
offspring

MRID 00162525; Forbis et
al. 1986

A

Oncorhynchus

mykiss

0.640

1.400

Reduced length and
wet weight

MRID 41475801; Tank et al.
1990;

MRID 41475802; Rhodes
and McCallister 1990

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species

(e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Chronic Benchmark Values

The OPP invertebrate chronic benchmark is 0.03 |ig/L, which is the NOEC for Daphnia magna.

The OPP fish chronic benchmark is 0.10 |ig/L, which is the estimated NOEC for Lepomis
macrochirus. Bluegill sunfish sensitivity to terbufos on a chronic basis was estimated using an
acute to chronic ratio (ACR) because it is the most acutely sensitive species. The ACR was based
on rainbow trout (acute and chronic toxicity) and bluegill sunfish (acute toxicity) data.

GLI Tier II Chronic Value Calculation

Paired quantitative acute and chronic toxicity data were available for water flea (Daphnia
magna) and rainbow trout (Oncorhynchus mykiss) allowing for the calculation of two ACRs.
While the chronic tests used >90% pure terbufos, the acute tests did not. Per the GLI Tier II
methodology, the default value of 18 was used to fulfill the remaining ACR. The acute and
chronic tests for water flea (Daphnia magna) and rainbow trout (Oncorhynchus mykiss) were
conducted in different laboratories, using water of different physical characteristics. Therefore,
the OPP approach was used to calculate the SACR, which involves the use of the NOAEC value.
The calculated SCV for terbufos is 0.0014 |ig/L.

Detailed calculations for the SCV are shown below:

147


-------
= Geometric Mean of the ACRs
= V 13.33 * 14.69 * 18 = 15.22

SACR
0.021

— = 0.0014 w/i

Table 6. Summary and comparison of chronic values for terbufos.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio >1 indicates the OPP value is higher than the OW value.	

Pesticide

OPP Invertebrate

ALB
(NOAEC) (Year
published, species)

OW Tier II value
(# of ACRs filled,

magnitude
relative to ALB)

OW Invertebrate-

only HCos
(# of ACRs filled,

magnitude
relative to ALB)

Notes

Terbufos

0.03 ng/L
(2023, Daphnia
magna)

0.0014 (ig/L
(GLI Tier II; 2
ACRs, 2IX)

NA

One default ACR of 18
used to derive GLI Tier II
value.

1.2.5.3 Terbufos References

ECOTOX 14097. Call D.J., Poirier S.H., Lindberg C.A., Harting S.L., Markee T.P., Brooke L.T.,
Zarvan N., and Northcott C.E. 1989. Toxicity of Selected Uncoupling and Acetylcholinesterase-
Inhibiting Pesticides to the Fathead Minnow (Pimephales promelas). In: D.L.Weigmann (Ed.),
Pesticides in Terrestrial and Aquatic Environments, Proc.Natl.Res.Conf., Virginia Polytechnic
Inst.and State Univ., Blacksburg, VA : 317-336.

ECOTOX 153854. Choung C.B., Hyne R.V., Stevens M.M., and Hose G.C. 2011. Toxicity of
the Insecticide Terbufos, Its Oxidation Metabolites, and the Herbicide Atrazine in Binary
Mixtures to Ceriodaphnia cf dubia. Arch. Environ. Contam. Toxicol. 60(3): 417-425.

ECOTOX 18475. Fornstrom C.B., Landrum P.F., Weisskopf C.P, and LaPoint T.W. 1997.
Effects of Terbufos on Juvenile Red Swamp Crayfish (Procambarus clarkii): Differential Routes
of Exposure. Environ. Toxicol. Chem. 16(12): 2514-2520.

ECOTOX 6797. Mayer F.L.J, and Ellersieck M.R. 1986. Manual of Acute Toxicity:
Interpretation and Data Base for 410 Chemicals and 66 Species of Freshwater Animals. Resour.
Publ. No. 160, U.S. Department of Interior, Fish and Wildlife Services, Washington, DC 505 p.

MRID 00037483. Sleight B.H., III. 1972. The Acute Toxicity of CycocelA(R)4 and Experimental
Insecticide AC 92,100 to Bluegill (-Lepomis mac~[j,-[j~rochirus~[j,) and Rainbow Trout (-Salmo
gairdneri~[j,). (Unpublished study received Apr 9, 1973 under 3G1340; prepared by Bionomics,
Inc., submitted by American Cyanamid Co., Princeton, N.J.; CDL:093584-U).

MRID 00085176. Bentley, R. E., and K. J. Macek. 1973. Acute Toxicity of Counter to Bluegill
{Lepomis macrochirus), Channel Catfish (Ictaluruspimctatus) and crayfish {Procambarus

SACR :
SACR :

SCV =
SCV =

148


-------
clarkii). Unpublished study conducted by Bionomic, Inc, Wareham, MA. Sponsored by
American Cyanamid Company, Princeton, NJ. Completed September 1973.

MRID 00087718. Roberts S., and WineholtR.L. 1976. Static 96-hour Toxicity Study of
Terbufos in Bluegill Sunfish and Brown Trout: Laboratory No. 6E-3166. (Unpublished study
received Nov 24, 1976 under 2749-427; prepared by Cannon Laboratories, Inc., submitted by
Aceto Chemical Co., Inc., Flushing, N.Y.; CDL:226951-A).

MRID 00101495. Boudreau, P., A. D. Forbis, and L. Franklin. 1982. Acute Toxicity of
COUNTER® terbufos to Daphnia magna. Unpublished study conducted by Analytical Bio-
Chemistry Laboratories, Inc, Columbia Missouri. Report No. 28686. Sponsored by American
Cyanimid Company, Princeton, NJ. Completed March 16, 1982.

MRID 00162525. Forbis A., Land C., and Bunch B. 1986. Chronic Toxicity of CL 92, 100 to
Daphnia magna Under Flow-Through Test Conditions: ABC Final Rept. #32891. Unpublished
study prepared by Analytical Bio-Chemistry Laboratories, Inc. 164 p.

MRID 41475801.Tank S., Brewer L., Cobb G. et al. 1990. Third Year Investigation of the
Response of Selected Wildlife Populations to Planting Time Application of Counter 15G
Systemic Insecticide-nematicide in an Iowa Corn Agroecosystem: Project Number 107.
Unpublished study prepared by The Institute of Wildlife & Environmental Toxicology. 753 p.

MRID 41475802. Rhodes J., and McAllister W. 1990. Early Life Stage Toxicity of [Carbon 14]-
AC 92,100 to the Rainbow Trout (Oncorhynchus mykiss) under Flow-through Conditions: Final
Report # 37913. Unpublished study prepared by Analytical Bio-Chemistry Laboratories, Inc. 648
P-

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2015. Registration review: Ecological risk assessment for terbufos. Office of Pesticide
Programs. Washington, D.C. September 15, 2015.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and the Clean Water Act
(CWA). EPA-820-D-24-002.

149


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1.3 Data Insufficient Pesticides

1.3.1 Comparison of Aquatic Life Toxicity Values for Methamidophos: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
(CWA) (U.S. EPA 2024) for methamidophos Data were gathered by the EPA in 2015 and were
also obtained from the OPP registration review document for methamidophos (U.S. EPA 2008).

1.3.1.1 Methamidophos Acute Toxicity Data

Acute data were gathered by the EPA in 2015 and were also obtained from the OPP registration
review document for methamidophos (U.S. EPA 2008; See Table 1). The data review identified
five LCsos for three species representing three genera that were classified as "quantitative" data.

Four additional 48-hour LC50S for Daphnia magna were classified as qualitative. Three LCsos
had standard duration (48-hr) and higher purity (>99% a.i. vs. 72-74% a.i. for the quantitative
tests), and were classified as qualitative because water chemistry was not reported, control
mortality was unknown, and specific test concentrations were not reported. The fourth (27 |ig/L)
was classified as qualitative because it was tested at 24°C but included here because it was a
standard duration test included in the OPP document. Two additional 96-hour LC50 for bluegill
(Lepomis macrochirus) were classified as qualitative. One was a static test with insufficient
information, and the other used polyethylene liners in test chambers. Both were included in the
OPP document. A 96-hour LC50 for the common carp (Cyprinus carpio) was classified as
qualitative because "chronic impacts observed by 48 hours", but included here because it was
used to fulfill an MDR group.

The final acute methamidophos dataset consisted of 12 LCsos for four species across four genera,
of which one was an invertebrate species. The invertebrate SMAV and GMAV for (Daphnia
magna) is listed in Table 2.

150


-------
Table 1. Acute toxicity data of methamidophos to fres

lwater aquatic organisms.

()\\
MIJR

(iroup'1

(Ion us

Species

I.C50/
IX 50

(M8/I-)

S\1 AY

(MB/I-)

(IMAY
(fili/l)

Reference

Comment

D

Daphnia

magna

26.00





MRID 00041311. Nelson
andRoney. 1979

Quantitative, 74% a.i.

D

Daphnia

magna

50.00





MRID 00014110. Wheeler.
1978

Quantitative, 72% a.i.

D

Daphnia

magna

33.66





ECOTOX 99572. Lin et al.
2006.

Qualitative, >99.0 a.i., Basic water chemistry not
reported; control mortality unknown; chemical
application rates not reported; monitoring of
concentrations not reported; test solution not
described

D

Daphnia

magna

33.46

32.74

32.74

ECOTOX 99572. Lin et al.
2006.

Qualitative, >99.0 a.i., Basic water chemistry not
reported; control mortality unknown; chemical
application rates not reported; monitoring of
concentrations not reported; test solution not
described

D

Daphnia

magna

235.5





ECOTOX 99572. Lin et al.
2006.

Qualitative, >99.0 a.i., Basic water chemistry not
reported; control mortality unknown; chemical
application rates not reported; monitoring of
concentrations not reported; test solution not
described

D

Daphnia

magna

27.00





MRID 00014305. Nelson
and Burke. 1977.

Qualitative, 74% a.i., Classified by OPP. Test
temperature 24°C

A

Oncorhynchus

mykiss

25,000

35,707

35,707

MRID 00041312. Nelson
andRoney. 1979.

Quantitative, 74% a.i.

A

Oncorhynchus

mykiss

51,000

MRID 00014063. Schoenig.
1968.

Quantitative, 75% a.i.

C

Cyprinus

carpio

68,000

68,000

68,000

MRID 05008361. Further
reference information is not
available.

Qualitative, 75% a.i., Classified by OPP. Chronic
impacts observed by 48 hours

B

Lepomis

macrochirus

34,000





MRID 00041312. Nelson
andRoney. 1979.

Quantitative, 74% a.i.

B

Lepomis

macrochirus

45,000

41,287

41,287

MRID 44484402. USEPA.
1977.

Qualitative, 75.4% a.i., Classified by OPP. Static
jar study with insufficient environmental
information

B

Lepomis

macrochirus

46,000





MRID 00014063. Schoenig.
1968.

Qualitative, 75% a.i., Classified by OPP.
Polyethylene liners used in test

151


-------
a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species (e.g., bluegill, channel catfish,
etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

152


-------
OPP Acute Benchmark Values

The OPP invertebrate acute benchmark is 13 |ig/L, which is V2 of the Daphnia magna LC50 of 26
Hg/L.

The OPP fish acute benchmark is 12,500 |ig/L, which is V2 of the Oncorhynchus mykiss LC50 of
25,000 |ig/L.

GLI Tier II Acute Value Calculation

The acceptable acute dataset for methamidophos fulfills four MDRs, corresponding to the use of
a Secondary Acute Factor (SAF) of 7. Applying the SAF to the lowest, most sensitive GMAV
(i.e., 36.06 |ig/L for water flea (Daphnia magna), the calculated Secondary Acute Value (SAV)
is 5.151 |ig/L. The Secondary Maximum Criterion (SMC), which is calculated as half the SAV,
is 2.575 |ig/L.

Detailed calculations for the SMC are shown below:

Lowest GMAV

SAF
36.06

—- = 5.151 \ig/L

SAV
~2~

5.151

—— = 2.575 |xg/L
Genus-Level Invertebrate-Only Acute HC05

No genus-level invertebrate acute HC05 could be calculated following the USEPA (1985)
methodology because there was only one invertebrate genus (Table 2).

Table 2. Methamidophos inverte

irate SMAV and GMAV (jug/L)



(Ion us

Species

S\1 AY

(IMAY

CMAY kiink

Daphnia

magna

32.74

32.74

1

SAV =
SAV =
SMC =
SMC =

153


-------
Table 3. Summary and comparison of acute values for methamidophos.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

ratio >1 indicates the OPP value is

ligher than the OW value.

Pesticide

OPP Invertebrate
ALB
(lowest LCso/2)
(Year published,
species)

OW GLI Tier II

value
(# of MDRs filled,

magnitude
relative to ALB)

OW Genus-

level
Invcrtcbratc-
onlv H Cos/2

Notes

Methamidophos

13 ng/L

(2016; Daphnia
magna)

2.58 ng/L
(4 MDRs filled,
5X)

NA

(1 genus)

The Tier II value is approximately
20% of the FIFRA ALB despite both
being based on the same species.

This is because of the Tier II
adjustment factor of 7 was applied to
this dataset, which satisfied 4/8
MDRs.

Figure 1 shows a genus-level sensitivity distribution for the methamidophos dataset. Major
taxonomic groups are delineated by different symbols, and invertebrate genera are identified by
name. Lines denoting the OPP acute benchmark values and GLI Tier II calculated value are
included.

154


-------
100,000.00

10,000.00

QUO

3

l/l

0

-C
Q.

*E

(0
-C

4->

01

1,000.00

100.00

10.00

1.00

• Arthropod

~

¦ Salmonid Fish

¦ D

~ Other Fish



~ Other Fish (Qualitative)

OPP Fish Benchmark= 12,500 pg/L

	 OPP Invert. Benchmark



- ¦ - OPP Fish Benchmark



	GLI Tier II



i Daphnia

0.0

0.1

0.2

0.3

Genus-level Invertebrate HC05/2 could not be calculated

OPP Invertebrate Benchmark = 13 pg/L

GLI Tier II Acute Value =2.58 pg/L

0.4

0.5

0.6

0.7

0.8

0.9

1.0

Sensitivity Centile

Figure 1. Methamidophos genus-level acute SD.

Symbols represent GMAVs calculated using all available data from the 2015 EPA literature search, supplemented with the OPP
registration review document for methamidophos (U.S. EPA 2008).

155


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1.3.1.2 Methamidophos Chronic Toxicity Data

Chronic data were gathered by the EPA in 2015 and combined with the OPP registration review
document for methamidophos (U.S. EPA 2008). The final chronic methamidophos dataset
consisted of one NOEC and one LOEC for a single species, which was an invertebrate (Table 4).

Table 4. Chronic toxicity data of methamidophos to freshwater aquatic organisms.

o\\

MDR

Croup'

(Ion us

Species

NOW

(M8/U

I.OIX

Knilpoinl

Reference

Comment

D

Daphnia

magna

4.490

5.320

Dry weight,
immobility and
reproduction

MRID

46554501. Kern
et al. 2005

Quantitative /
Supplemental

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species

(e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Chronic Benchmark Values

The OPP invertebrate chronic benchmark is 4.5 |ig/L, which is the NOEC for Daphnia magna.

The OPP fish chronic benchmark is 173.6 |ig/L, which is the estimated NOEC for Oncorhynchus
mykiss. The 0. mykiss NOEC was extrapolated by dividing the most sensitive acute 96-h LC50
for rainbow trout (25,000 |ig/L) by 144 (highest rainbow trout ACR for organophosphates).

GLI Tier II Chronic Value Calculation

Paired quantitative chronic and acute toxicity data for methamidophos were available for the
water flea, Daphnia magna. The paired acute and chronic D. magna data enabled the calculation
of one ACR. The remaining two ACRs were fulfilled by the default value of 18. The acute and
chronic tests were conducted in different laboratories using water of different physical
characteristics; therefore, OPP's approach was used to calculate the ACR. OPP's approach
involves the use of the NOAEC in the calculations. The calculated Secondary Chronic Value
(SCV) for methamidophos is 0.418 |ig/L.

Detailed calculations for the SCV are shown below:

SACR = Geometric Mean of the ACRs
SACR = a/5.791 * 18 * 18 = 12.33

SCV =

SACR
5.151

scv=im=0AlsM/L

156


-------
Table 6. Summary and comparison of chronic values for methamidophos.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

ratio >1 indicates the OPP value is hig

ier than the OW value.

Pesticide

OPP Invertebrate

ALB
(NOAEC) (Year
published, species)

OW Tier II

value
(#of ACRs
filled, magnitude
relative to ALB)

OW Invertebrate-

only HCos
(# of ACRs filled,

magnitude
relative to ALB)

Notes

Methamidophos

4.5 (ig/L
(2016, Daphnia
magna)

0.42 (ig/L
(GLI Tier II; 1
ACR, 11X)

NA

Two default ACRs of 18
used to derive GLI Tier
II value.

1.3.1.3 Methamidophos References

ECOTOX 99572. Lin K., Zhou S., Xu C., Liu W. 2006. Enantiomeric Resolution and Biotoxicity
of Methamidophos. J Agric Food Chem 54(21): 8134-8138.

MRID 00014063. Schoenig, G. 1968. Report to Chevron Chemical Company, Ortho Division:
Four-Day Fish Toxicity Study on Monitor (RE-9006) 75% Technical SX-171:IBT No. A6482.
(Unpublished study received Mar 5, 1970 under 0F0956; prepared by Industrial Bio-Test
Laboratories, Inc., submitted by Chevron Chemical Co., Richmond, Calif.; CDL:093265-W).

MRID 00014110. Wheeler, R.E. 1978. 48 Hour Acute Static Toxicity of Monitor (SX887) to 1st
Stage Nymph Water Fleas (Daphnia magna Straus). (Unpublished study received Sep 15, 1978
under 239-2404; submitted by Chevron Chemical Co., Richmond, Calif.; CDL:235153-A).

MRID 00014305. Nelson, D.L.; Burke, M.A. 1977. Acute Toxicity of Vi(R) Monitor Technical
to Daphnia magna: Report No. 54045. (Unpublished study received Mar 27, 1978 under 3125-
280; submitted by Mobay Chemical Corp., Agricultural Div., Kansas City, Mo.; CDL: 238096-
C.

MRID 00041311. Nelson, D.L.; Roney, D.J. 1979 Acute Toxicity of Monitor Vi(R) Technical to
Bluegill and Rainbow Trout: Report No. 67739. (Unpublished study received Mar 19, 1980
under 3125-280; submitted by Mobay Chemical Corp., Kansas City, Mo.; CDL:242410-C).

MRID 00041312. Nelson, D.L.; Roney, D.J. 1979 Acute Toxicity of Monitor Vi(R) Technical to
Bluegill and Rainbow Trout: Report No. 67739. (Unpublished study received Mar 19, 1980
under 3125-280; submitted by Mobay Chemical Corp., Kansas City, Mo.; CDL:242410-C).

MRID 05008361. Chin, Y. N. and K. I. Sudderuddin. 1979. Effect of methamidaphos on the
growth rate and esterase activity of the common carp Cyprimts carpio. Environmental Pollution
18(3): 213-220.

MRID 44484402. United States Environmental Protection Agency. 1977. Biological Report of
Analysis: Bluegill: Monitor 75.39%: Lab Project Number: TSD 1.206. Unpublished study. 6 p.

MRID 46554501. Kern, M.E., and C.V. Lam. 2005. Chronic Toxicity of Methamidophos to the
Daphnia magna Under Flow-Through Conditions. Unpublished study performed by Bayer Crop

157


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Science, Stilwell, KS. Laboratory Study No. EBTAX016. Study submitted by Bayer
CropScience, Research Triangle Park, NC. Study initiated November 3, 2004 and submitted
April 6, 2005.

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2008. Registration review. Ecological risk assessment problem formulation for:
methamidophos. Office of Pesticide Programs. Washington, D.C. September 29, 2008.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

158


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1.3.2 Comparison of Aquatic Life Toxicity Values for Profenofos: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
('CWA) (U.S. EPA 2024) for profenofos were gathered by the EPA in 2015 and were also
obtained from the OPP registration review document for profenofos (U.S. EPA 2008).

1.3.2.1 Profenofos Acute Toxicity Data

Acute data were gathered by the EPA in 2015 and were also obtained from the OPP registration
review document for profenofos (U.S. EPA 2008; See Table 1). Six LCsos for five species
representing five genera that were classified as "quantitative" data. Five LCsos for four
invertebrate species across three genera were classified as qualitative and are included here to
allow for a sufficient sample size to calculate an invertebrate genus-level HCos.

One 48-hour LCso for Chironomusplumosus classified as qualitative because of duration used to
fulfill an MDR group. One 48-hour LCso for Ceriodaphnia dubia classified as qualitative
because water quality characteristics were not reported and potential exposure from feeding may
have occurred. Three 24-hour LCsos for two species of Culex classified as qualitative because of
duration. One 96-hour LCsos for fathead minnow Pimephalespromelas classified as qualitative
because control mortality was not reported and feeding may have occurred. One 96-hour LCso
for the Western mosquitofish Gambusia affinis classified as qualitative because source water was
unknown and control mortality was not reported.

The final acute profenofos dataset consisted of 13 LCsos for 11 species representing 10 genera, of
which six were invertebrate species representing five invertebrate genera. Ranked invertebrate
GMAVs are listed in Table 2.

159


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Table 1. Acute toxicity data of profenofos to freshwater aquatic organisms.

()\\
MDR

(iroup-1

(Ion us

Species

IX 50/
I X 50

(Mli/I.)

S\1 AY

(M8/U

(IMAY

(M8/U

Reference

Comment

D

Ceriodaphnia

dubia

0.039

0.039

0.04

ECOTOX 158195; Woods et al.
2002

Qualitative, water quality characteristics
not reported; potential exposure from
feeding; source water type unknown

D

Daphnia

magna

1.400

1.14

1.14

ECOTOX 6797; Mayer and
Ellersieck. 1986

Quantitative

D

Daphnia

magna

0.930

MRID 416273-04; Bellantoni.
1990

Quantitative

F

Culex

pipiens pallens

73

73.010

28.67

ECOTOX 61915; Lee et al. 1997

Qualitative

F

Culex

quinquefasciatus

5.13

11.26

ECOTOX 63336; Kasai et al.
1998

Qualitative

F

Culex

quinquefasciatus

24.7

ECOTOX 63336; Kasai et al.
1998

Qualitative

E

Gammarus

pseudolimnaeus

0.800

0.800

0.80

ECOTOX 6797; Mayer and
Ellersieck. 1986

Quantitative

F

Chironomus

plumosus

1.000

1.000

1.00

ECOTOX 6797; Mayer and
Ellersieck. 1986

Qualitative, duration

A

Oncorhynchus

mykiss

23.50

23.50

23.50

ECOTOX 6797; Mayer and
Ellersieck. 1986

Quantitative

C

Pimephales

promleas

316.4

316.4

316.4

ECOTOX 68287; Baer et al.
2002

Qualitative, Dechlorinated tap water used;
nominal; control mortality not reported;
possible feeding during test

C

Gambusia

affinis

633.6

633.6

633.6

ECOTOX 100565; Rao et al.
2006

Qualitative, Control mortality unknown;
source water

B

Lepomis

macrochirus

13.50

13.50

13.50

ECOTOX 6797; Mayer and
Ellersieck. 1986

Quantitative

C

Ictalurus

punctatus

18.00

18.00

18.00

ECOTOX 6797; Mayer and
Ellersieck. 1986

Quantitative

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species (e.g., bluegill, channel catfish,
etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

160


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G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

161


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OPP Acute Benchmark Values

The OPP invertebrate acute benchmark is 0.465 |ig/L, which is V2 of the lowest Daphnia magna
LC50 of 0.930 |ig/L.

The OPP fish acute benchmark is 7.05 |ig/L, which is V2 of the Lepomis macrochirus LC50 of
14.1 |ig/L as it is reported in the OPP document. The value listed (14.1) is based on nominal
concentration and is listed as a measured concentration (13.5) in Table 1.

GLI Tier II Acute Value Calculation

The acceptable acute dataset for profenofos fulfills six of the eight MDRs, corresponding to the
use of a SAF of 5.2. Applying the SAF to the lowest, most sensitive GMAV (i.e., 0.800 |ig/L for
scud (Gammaruspseudolimnaeus), the calculated Secondary Acute Value (SAV) is 0.154 |ig/L.
The SMC, which is calculated as half the SAV, is 0.077 |ig/L. Detailed calculations for the SMC
are shown below:

Lowest GMAV

0.800

SAV = -^-= 0.154 \ig/L
SAV

SMC =	

2

0.154

SMC = —— = 0.077 \ig/L

Genus-Level Invertebrate-Only Acute HC05

No genus-level invertebrate acute HC05 could be calculated following the USEPA (1985)
methodology, as there was only two invertebrate genera with quantitative data (Table 2).

Table 2. Profenofos invertebrate SMAVs and G

MAVs (jig/L).

(Ion us

Species

S\1 AY

(IMAY

CMAY kit 11k

Daphnia

magna

1.141

1.141

2

Gammarus

pseudolimnaeus

0.8000

0.8000

1

162


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Table 3. Summary and comparison of acute values for profenofos.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio >1 indicates the OPP value is higher than the OW value.	

Pesticide

OPP Invertebrate
ALB

(lowest LCso/2) (Year
published, species)

OW GLI Tier II value

(# of IMDRs filled,
magnitude relative to
ALB)

OW Genus-level
Invertebrate-
only HCos/2

Notes

Profenofos

0.465 ng/L
(2008; Daphnia
magna)

0.077 ng/L
(6 MDRs filled, 6X)

NA

(2 genera)

The FIFRA ALB is higher
because the GLI Tier II value
is based on G. pseudolimnaeus
test in the open literature with
a lower LC50.

Figure 1 shows a genus-level sensitivity distribution for the profenofos dataset. Major taxonomic
groups are delineated by different symbols, and invertebrate genera are identified by name. Lines
denoting the OPP acute benchmark values and GLI Tier II calculated acute value are included.

163


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1,000.000 -|

100.000

10.000

CUD

3.

10

o

H—

o
£

£
o

1.000

0.100

0.010

0.001

•

Arthropod

o

Arthropod (Qualitative)

¦

Salmonid Fish

~

Other Fish

~

Other fish (Qualitative)



OPP Invert. Benchmark

	

OPP Fish Benchmark

	

GLI Tier II Acute Value

Gammarus •

O Ceriodaphnia

~

Chironomus
O	• Daphnia

O Culex

OPP Fish Benchmark = 7.05 pg/L

OPP Invertebrate Benchmark = 0.465 ^ig/L

GLIT Tier II Acute Value =0.077 pg/L

Genus-level Invertebrate cannot be calculated

0.0

0.1

0.2

0.3	0.4	0.5	0.6

Sensitivity Centile

0.7

0.8

0.9

1.0

Figure 1. Profenofos genus-level SD.

Symbols represent GMAVs calculated using all available data from the 2015 EPA literature search, supplemented with the OPP
registration review document for profenofos (U.S. EPA 2015).

164


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1.3.2.2 Profenofos Chronic Toxicity Data

Chronic data were gathered by the EPA in 2015 and supplemented with the OPP registration
review document for profenofos (U.S. EPA 2015). The final chronic profenofos dataset consisted
of two NOECs/LOECS for two species across two genera, of which one was an invertebrate and
one was a vertebrate (Table 5).

Table 5. Chronic toxicity data of profenofos to freshwater aquatic organisms

()\\
MDR
C> roil p'

(.onus

Species

Nor.c

I.OIX

(flii/l.)

I'lmlpoini

KiTciyiiit

( (Mil 111011 (

D

Daphnia

magna

0.2

0.33

Survival of
parent and
offspring

MRID 000859-64;
LeBlanc and
Suprenant 1980

Quantitative

B

Pimephales

promelas

2.0

4.4

Not defined

MRID 000859-58;
LeBlanc et al. 1979

-

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species

(e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Chronic Benchmark Values

The OPP invertebrate chronic benchmark is 0.2 |ig/L, which is the NOEC for Daphnia magna.
The OPP fish chronic benchmark is 2.0 |ig/L, which is the NOEC for Pimephalespromelas.

GLI Tier II Chronic Value Calculation

Quantitative chronic toxicity data and an analogous acute test for profenofos are available for the
water flea, Daphnia magna, enabling the calculation of one ACR. The default value of 18 was
used to fulfill the second and third ACRs. The acute and chronic tests for water flea (Daphnia
magna) were conducted in different laboratories using water of different physical characteristics;
therefore, OPP's approach was used to calculate the ACR, which involves the use of the NOAEC
in the calculation. The calculated SCV for profenofos is 0.013 |ig/L. Detailed calculations for the
SCV are shown below:

= Geometric Mean of the ACRs

= 3V4.650* 18* 18 = 11.46

SAV
SACR

SACR :
SACR :

SCV =

165


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0.154

SCV = U46 = 0'013 Vi9/L

Table 6. Summary and comparison of chronic values for profenofos.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

ratio >1 inc

icates the OPP value is higher than the OW value.

Pesticide

OPP Invertebrate

ALB
(NOAEC) (Year
published, species)

OW Tier II value
(# of ACRs filled,
magnitude relative to
ALB)

OW Invertebrate-only
HCos
(# of ACRs filled,
magnitude relative to
ALB)

Notes

Profenofos

0.2 ng/L
(2016, Daphnia
magna)

0.013 ng/L

(GLI Tier II; 1 ACR,

15X)

NA

Two default ACRs of
18 used to derive
GLI Tier II value.

1.3.2.3 Profenofos References

ECOTOX 100565. Rao, J.V., Begum, G., Jakka, N.M., Srikanth, K., and Rao, R.N. 2006.
Sublethal Effects of Profenofos on Locomotor Behavior and Gill Architecture of the Mosquito
Fish, Gambusia affinis. Drug Chem. Toxicol. (N.Y.) 29(3): 255-267.

ECOTOX 158195. Woods, M., Kumar, A., and Correll, R. 2002. Acute Toxicity of Mixtures of
Chlorpyrifos, Profenofos, and Endosulfan to Ceriodaphnia dubia. Bull. Environ. Contam.
Toxicol. 68(6): 801-808.

ECOTOX 61915. Lee, D.K., Shin, E.H., and Shim, J.C. 1997. Insecticide Susceptibility of Culex
pipiens pallens (Culicidae, Diptera) Larvae in Seoul. Korean J. Appl. Entomol. 27(1): 9-13.

ECOTOX 63336. Kasai, S., Weerashinghe, I.S., and Shono, T. 1998. P450 Monooxygenases are
an Important Mechanism of Permethrin Resistance in Culex quinquefasciatus Say Larvae. Arch.
Insect Biochem. Physiol. 37(1): 47-56.

ECOTOX 6797. Mayer, F.L.J, and Ellersieck, M.R. 1986. Manual of Acute Toxicity:
Interpretation and Data Base for 410 Chemicals and 66 Species of Freshwater Animals. Resour.
Publ. No. 160, U.S. Department of Interior, Fish and Wildlife Services, Washington, DC 505 p.

ECOTOX 68287. Baer, K.N., Olivier, K, and Pope, C.N. 2002. Influence of Temperature and
Dissolved Oxygen on the Acute Toxicity of Profenofos to Fathead Minnows (Pimephales
promelas). Drug Chem. Toxicol. (N.Y.) 25(3): 231-245.

MRID 000859-58. LeBlanc, G.A., Hoberg, J.R, and Dean, J.W. (1979) The Toxicity of CGA-
15324 to Fathead Minnow (Pimephales promelas) Eggs and Fry: Report #BW-79-6-490.
(Unpublished study received Nov 6, 1981 under 100-598; prepared by EG & G, Bionomics,
submitted by Ciba- Geigy Corp., Greensboro, N.C.; CDL:246216-L).

MRID 000859-64. LeBlanc and Surprenant. 1980. Acute toxicity of priority pollutants to water
flea (Daphnia magna). Bulletin of Environmental Contamination and Toxicology. Volume 24,
Issue 1, pp 684-691.

166


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MRID 416273-04. Bellantoni, D.C. 1990. Profenofos Technical: A 48-Hour Static Acute
Toxicity Test with the Cladoceran (Daphnia magna). Laboratory Study No. 108A-106. Prepared
by Wildlife International Ltd., Easton, MD. Submitted by Agricultural Division, Ciba-Geigy
Corporation, Greensboro.

Mayer, F.L.J, and Ellersieck, M.R. 1986. Manual of Acute Toxicity: Interpretation and Data
Base for 410 Chemicals and 66 Species of Freshwater Animals. Resour. Publ. No. 160, U.S.
Department of Interior, Fish and Wildlife Services, Washington, DC 505 p.

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2008. Problem formulation for the environmental fate, ecological risk, endangered
species, and drinking water assessments in support of the registration review of profenofos.
Office of Pesticide Programs. Washington, D.C. March 31, 2008.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

167


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1.3.3 Comparison of Aquatic Life Toxicity Values for Fenpropathrin: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
('CWA) (U.S. EPA 2024) for fenpropathrin were gathered by OW in 2015 and combined with
data from the OPP document on which the benchmark values are based (U.S. EPA 2010) and
information in an OPP (Sayer 2016) memo reviewing studies submitted in support of the
fenpropathrin review was also considered below.

1.3.3.1 Fenpropathrin Acute Toxicity Data

Acute fenpropathrin data were gathered by OW in 2015. The OPP document on which the
benchmark values are based (U.S. EPA 2010) and an OPP (Sayer 2016) memo reviewing studies
submitted in support of the fenpropathrin review were also included in the data gathering (See
Table 1). Four LCsos representing four species in four genera were identified and classified as
"quantitative" data. A 96-hour LCso for rainbow trout (Oncorhynchus mykiss) was identified and
classified as qualitative because it was an 89% a.i. solution but considered acceptable in the OPP
document. Two 24-hour LCsos for the Southern house mosquito (Culex quinquefasciatus)
classified as qualitative for multiple reasons (duration, concentrations used not reported, control
not reported, source of organisms unknown, tap water used), but included here to increase the
number of invertebrate genera. Additionally, a review of studies submitted in support of a
registration review was examined (Sayer 2016), and an acceptable 96-hour LCso for the
amphipod species, Hyalella azteca, was added.

The final acute fenpropathrin dataset consisted of eight LCsos for seven species across seven
genera, of which three were invertebrate species representing three invertebrate genera. Ranked
invertebrate GMAVs are listed in Table 2.

168


-------
Table 1. Acute toxicity data of fenpropathrin to freshwater aquatic organisms.

()\\
MDR

(iioup'

(Ion us

Species

I.C50/
I X 50
(MS/I.)

S\1 AY

(MS/'-)

(IMAY

(M8/U

Reference

Comment

D

Daphnia

magna

0.530

0.53

0.53

MRID 249939

Quantitative

E

Hyalella

azteca

0.00305

0.00305

0.00305

MRID 49209502. Bradley. 2013.



F

Culex

quinquefasciatus

0.27000

0.6148

0.6148

ECOTOX 10971

Qualitative: Duration, tap water,
static, concentrations not reported,
control mortality not reported (larvae)

F

Culex

quinquefasciatus

1.40000

ECOTOX 10971

Qualitative: Duration, tap water,
static, concentrations not reported,
control mortality not reported (pupae)

A

Oncorhynchus

mykiss

2.3

2.30

2.30

MRID 249939

Qualitative, 89% a.i.













MRID 41525901. Dionne and



B

Pimephales

promelas

2.370

2.37

2.37

Suprenant. 1990

MRID 42360001. Dionne and

Suprenant. 1992

Quantitative

B

Lepomis

macrochirus

2.200

2.20

2.20

MRID 249939
MRID 00127791

Quantitative

B

Ictalurus

punctatus

5.500

5.50

5.50

MRID 249939

Quantitative

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species (e.g., bluegill, channel catfish,

etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

169


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OPP Acute Benchmark Values

The OPP invertebrate acute benchmark is 0.0015 |ig/L, which is V2 of the Hyalella azteca LC50
of 0.00305 |ig/L.

The OPP fish acute benchmark is 1.1 |ig/L, which is V2 of the Lepomis macrochirus LC50 of 2.2

^g/L-

GLI Tier II Acute Value Calculation

The acceptable acute dataset for fenpropathrin fulfills five of the eight MDRs, corresponding to
the use of a SAF of 6.1. Applying the SAF to the lowest, most sensitive GMAV (i.e.,
0.00305|ig/L for Hyalella azteca), the calculated SAV is 0.0005 |ig/L. The SMC, which is
calculated as half the SAV, is 0.00025 |ig/L.

Detailed calculations for the SMC are shown below:

Lowest GMAV

0.00305

SAV =	= 0.0005 ag/L

6.1

SAV

SMC= —

0.0005

SMC = —-— = 0.00025 |xg/L

Genus-Level Invertebrate Acute HC05

No genus-level invertebrate acute HC05 could be calculated using the USEPA (1985)
methodology because there were only three invertebrate genera (Table 2).

Table 2. Fenpropathrin invertebrate SMAVs and GMAVs (^ig/L).

(iOIIIIS

Speck's

SMAY

CMAY

CMAY Kiink

Culex

quinquefasciatus

6.148

6.148

3

Daphnia

magna

0.5300

0.5300

2

Hyalella

azteca

0.00305

0.00305

1

Note: The Culex GMAV is based on data classified as qualitative that was included to increase the number of
invertebrate genera.

170


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Table 3. Summary and comparison of acute values for fenpropathrin.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

Pesticide

OPP

Invertebrate
ALB
(lowest
LCso/2) (Year
published,
species)

OW GLI Tier II
value
(# of MDRs

filled,
magnitude
relative to ALB)

OW Genus-

level
Invcrtcbratc-
onlv H Cos/2

Notes

Fenpropathrin

(Synthetic

Pyrethroid)

0.0015 ng/L
(2021;

Hyalella
azteca)

0.00025 ng/L
(5 MDRs filled,
6X)

NA

(2 genera)

The GLI Tier II value is lower than the
FIFRA ALB despite both being based
on the same species. This is because of
the Tier II adjustment factor of 6.1 was
applied to this dataset, which satisfied
5/8 MDRs.

Figure 1 shows a genus-level sensitivity distribution for the fenpropathrin dataset. Major
taxonomic groups are delineated by different symbols, and invertebrate genera are identified by
name. Lines denoting the OPP acute benchmark values and the GLI Tier II calculated value are
included.

171


-------
10.000

1.000

US

3 0-100

.£

JE

4-»

m

a,

o

•

Arthropod

o

Arthropod (Qualitative)

¦

Salmonid Fish

~

Other Fish



OPP Invert. Benchmark

	

OPP Fish Benchmark



-GLI Tier il Acute Value

Q.
C

V

0.010

0.001

Daphnia

Hyalella

O Culex

OPP Fish Benchmark = 1.1 jig/L

Genus-level Invertebrate HC05/2 could not be calculated

OPP Invertebrate Benchmark = 0,0015 fig/L

GLI Tier II Acute Value = 0.00025 (ig/L

0.000

0.0

0.1

0.2

0.3

0.4	0.5	0.6

Sensitivity Centile

0.7

0.8

0.9

1.0

Figure 1. Fenpropathrin genus-level acute SD.

Symbols represent GMAVs calculated using all available data from the EPA 2015 literature search supplemented with the OPP
registration review document for fenpropathrin (U.S. EPA 2010, Sayer 2016).

172


-------
1.3.3.2 Fenpropathrin Chronic Toxicity Data

Chronic fenpropathrin data were gathered by OW in 2015 and combined with data from the OPP
document on which the benchmark values are based (U.S. EPA 2010) and information in an OPP
(Sayer 2016) memo reviewing studies submitted in support of the fenpropathrin review was also
considered below.

The final chronic fenpropathrin dataset consisted of five NOECs/LOECS for four species across
four genera, of which three were invertebrate genera and one was a vertebrate genus (Table 4).

Table 4. Chronic toxicity data of fenpropathrin to freshwater aquatic organisms

OW
MIJR

(ll'Olip'1

(Ionus

Species

NOEC
(MS/I-)

I.OIX

(MS/'-)

Knilpoinl

Reference

Comment

D

Daphnia

magna

0.064

0.350

100% mortality at 0.350 |ig/L:
prior to mortality, significant
decrease in fecundity (mean
young/adult/reproduction day)

MRID 259678

Quantitative

E

Hyalella

azteca

0.004

0.0101

Survival

MRID 49243301

Acceptable

E

Hyalella

azteca

<0.0015

0.0015

Growth (length)

MRID 49368102

Supplemental
- qualitative

F

Chironomus

dilutus

0.00578

0.01494

Emergence rate

MRID 49316005

Acceptable

B

Pimephales

promelas

0.06

0.091

Not reported

MRID 41525901

Supplemental

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species

(e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Chronic Benchmark Values

The OPP invertebrate chronic benchmark is <0.0015 |ig/L, which is the NOEC for Hyalella
azteca.

The OPP fish chronic benchmark is 0.6 |ig/L, which is the NOEC for Pimephalespromelas.
GLI Tier II Chronic Value Calculation

The acceptable dataset includes paired quantitative chronic and acute toxicity data for water flea
(Daphnia magna), allowing for the calculation of one ACR. The GLI Tier II default value of 18
was used for the second and third ACRs. The acute and chronic water flea (Daphnia magna)
tests were conducted in different laboratories using water of different physical characteristics;
therefore, OPP's approach was used to calculate the ACRs. The Office of Pesticide Program's
approach involves the use of the lowest (i.e., most sensitive) NOAEC for a given species in the

173


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ACR calculations. The calculated SCV for fenpropathrin is 0.000036 |ig/L. Detailed calculations
for the SCV are shown below:

SACR = Geometric Mean of the ACRs
SACR = V8.281 * 18 * 18 = 13.90

SCV =	

SACR

0.0005

SCV = "l390" = 0-000036

Table 5. Summary and comparison of chronic values for fenpropathrin.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

ratio >1 indicates the OPP value is hig

ier than the OW value.

Pesticide

OPP Invertebrate

ALB
(NOAEC) (Year
published, species)

OW Tier II

value
(# of ACRs
filled, magnitude
relative to ALB)

OW Invertebrate-

only HCos
(# of ACRs filled,

magnitude
relative to ALB)

Notes

Fenpropathrin

<0.0015 (ig/L
(2021, Hyalella
azteca)

0.000036 ng/L
(GLI Tier II; 1
ACR, 42X)

NA

Two default ACRs of 18
used to derive GLI Tier
II value.

1.3.3.3 Fenpropathrin References

ECOTOX 10971. Mulla,M.S., H.A. Darwazeh, andL. Ede. 1982. Evaluation of New Pyrethroids
Against Immature Mosquitoes and Their Effects on Nontarget Organisms. Mosq. News, 42, (4),
583-590.

MRID 00127791. Acute Toxicity of S-3206 TGto Bluegill, Report #BW-81-8-988 by EG & GI
Bionomics submitted to Sumitomo Chemical Company, August 1981, Acc #249939.

MRID 249939. Acute Toxicity of S-3206 TG to Bluegill, Report #BW-81-8-988 by EG & GI
Bionomics submitted to Sumitomo Chemical Company, August 1981, Acc #249939.

MRID 259678. Forbis, Alan D., David Burgess, and Brenda Bunch. 1985. Chronic Toxicity of
(cyclopropyl-l-14C) fenpropathrin to Daphnia magna Under Plow-through Test Conditions.
Conducted at Analytical Bio-Chemistry Laboratories, Inc. Report # 32547. September 9, 1985.
Submitted to EPA by Sumitomo Chemical America, Inc. Acc. No. 259678.

174


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MRID 41525901. Dionne, E. and D.C. Suprenant. 1990. The chronic toxicity of Fenpropathrin to
the Fathead Minnow (Pimephalespromelas). Conducted by Springborn Laboratories, Inc.,
Wareham, Massachusetts. Laboratory Project No. S-2725. Laboratory Study No.
981.0687.6122.122. Submitted by Chevron Chemical Company, Richmond, California.

MRID 42360001. Dionne, E. and D. Suprenant. 1992. The Chronic Toxicity of Fenpropathrin
Fathead minnow (.Pimephales promelas): Supplement to: Lab Project 89-1-2913. Unpublished
study prepared by Springborn Labs., Inc. 328 p.

MRID 49209502. Bradley, M.J. 2013. Fenpropathrin TG - Acute Toxicity to Freshwater
Amphipods (Hyalella azteca) Under Flow-Through Conditions. Unpublished study performed by
Smithers Viscient, Wareham, MA. Laboratory Study No. 13656.6165. Study sponsored by
Pyrethroid Working Group, FMC Corporation, Ewing, NJ. Study initiated March 27, 2012 and
completed July 30, 2013.

MRID 49243301. Picard, C.R. 2013. Fenpropathrin TG - 42-Day Toxicity Test Exposing
Freshwater Amphipods (.Hyalella azteca) to a Test Substance Applied to Sediment Under Static-
Renewal Conditions Following EPA Test Methods. Unpublished study conducted by Smithers
Visient, Wareham, MA. Report No 12709.6335. Study sponsored by Valent USA Corporation,
Walnut Creek, CA Study completed October 15, 2013.

MRID 49316005. Picard, C.R. Life-Cycle Toxicity Test Exposing Midges (Chironomus dilutus)
to Fenpropathrin TG Applied to Sediment under Static-Renewal Conditions Following EPA Test
Methods. Unpublished study conducted by Smithers Visient, Wareham, MA. Report No
12709.6334. Study sponsored by Valent USA Corporation, Walnut Creek, CA Study completed
December 17, 2013.

MRID 49368102. Picard, C.R. 2014. 10-Day Toxicity Test Exposing Freshwater Amphipods
(.Hyalella azteca) to Fenpropathrin Applied to Sediment Under Static-Renewal Conditions
Unpublished study conducted by Smithers Visient, Wareham, MA. Report No 13656.6157.
Study sponsored by Pyrethroid Working Group, Ewing, NJ. Study completed April 3, 2014.

Sayer, A. 2016. Fenpropathrin: Review of ecological studies submitted in support of registration
review. Memorandum to OPP Pesticide Re-evaluation Division. April 9, 2016.

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2010. Environmental fate and ecological risk assessment problem formulation in
support of registration review for fenpropathrin. Office of Pesticide Programs. Washington, D.C.
June 16, 2010.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

175


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1.3.4 Comparison of Aquatic Life Toxicity Values for Fenbutatin Oxide: Data Sources
and Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
('CWA) (U.S. EPA 2024) for fenbutatin oxide were gathered by OW in 2015 and combined with
data obtained from the OPP registration review document for fenbutatin oxide (U.S. EPA 2009).

1.3.4.1 Fenbutatin Oxide Acute Toxicity Data

Acute fenbutatin oxide data were gathered by the EPA in 2015 and were also obtained from the
OPP registration review document for fenbutatin oxide (U.S. EPA 2009; See Table 1). Six LCsos
representing three species in three genera were identified and classified as "quantitative" data.
One 24-hour LCso for an unidentified insect species in the family Chironomidae was classified as
qualitative but included here to increase the number of invertebrate genera. The Chironomidae
test was classified as qualitative because of a non-standard exposure duration, the unidentified
species, and the non-definitive (>4,400 ng/L) LCso test result.

The final acute fenbutatin oxide dataset consisted of seven LCsos for four species across four
genera, of which two were invertebrate species representing two invertebrate genera. Ranked
invertebrate GMAVs are listed in Table 2.

176


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Table 1. Acute toxicity data of fenbutai

in oxide to freshwater aquatic organisms.

()\\
MDR

(iioup'

liimilv

(Ionus

Species

IX 50/
I X 50
(uii/l.)

S\1 AY

(MS/'-)

(IMAY

(MS/'-)

Reference

D

Daplmiidae

Daplmia

magna

31.UU

31.00

31.00

MRU) 4u4~3509. lluUon. 198"

F

Chironomidae

-

-

>4,400

>4,400

>4,400

MRID 47910407. Picard. 2005

A

Salmonidae

Oncorhynchus

mykiss

1.700

2.773

2.773

MRID 40098001. ECOTOX 6797. Mayer and Ellersieck. 1986.

A

Salmonidae

Oncorhynchus

mykiss

1.900

MRID 00113075. Johnson. 1973

A

Salmonidae

Oncorhynchus

mykiss

6.600

MRID 40473506. Hutton. 1987

B

Centrarchidae

Lepomis

macrochirus

4.800

4.800

4.800

MRID 40098001. ECOTOX 6797. Mayer and Ellersieck. 1986

B

Centrarchidae

Lepomis

macrochirus

4.800

MRID 00113076. Johnson and Jones. 1971

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species (e.g., bluegill, channel catfish,
etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

177


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OPP Acute Benchmark Values

The OPP invertebrate acute benchmark is 15.5 |ig/L, which is V2 of the Daphnia magna LC50 of
31.00 |ig/L.

The OPP fish acute benchmark is 0.85 |ig/L, which is V2 of the Oncorhynchus mykiss LC50S of
1.7|ig/L.

GLI Tier II Acute Value Calculation

The acceptable acute dataset for fenbutatin oxide fulfills three of the eight MDRs, corresponding
to the use of a SAF of 8. Applying the SAF to the lowest, most sensitive GMAV (i.e., 2.773 |ig/L
for rainbow trout (Oncorhynchus mykiss), the calculated SAV is 0.347 |ig/L. The SMC, which is
calculated as half the SAV, is 0.173 |ig/L.

Detailed calculations for the SMC are shown below:

Lowest GMAV

2.773

SAV = —— = 0.347 |xg/L

O

SAV

SMC= —

0.347

SMC = —= 0.173 |xg/L

Genus-Level Invertebrate-only Acute HC05

No genus-level invertebrate acute HC05 could be calculated following the USEPA (1985)
methodology because there were only two invertebrate genera (Table 2).

Table 2. Fenbutatin oxide invertebrate SMAVs and GMAVs (iig/L).

(Ion us

Species

S\1 AY

(IMAY

linerlehnile
CMAY kit 11k

I uiuiIn Cliii'oiioniidae



4,4UU

4,400



Daphnia

magna

31.00

31.00

1

Note: The Family Chironomidae GMAVs is based on data classified as qualitative that was included to increase the
number of invertebrate genera.

178


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Table 3. Summary and comparison of acute values for fenbutatin oxide.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

Pesticide

OPP Most Sensitive
ALB

(lowest LCso/2) (Year
published, species)

OW GLI Tier II

value
(# of IMDRs filled,
magnitude relative to
ALB)

OW Genus-level
Invcrtcb rate-only

HCos/2

Fenbutatin Oxide
(Organotin Acaricide)

0.85 ng/L

(2009; Oncorhynchus
mykiss)

0.173 ng/L
(3 MDRs filled, 4.9X)

NA

(1 genus)

Figure 1 shows a genus-level sensitivity distribution for the fenbutatin oxide dataset. Major
taxonomic groups are delineated by different symbols, and invertebrate genera are identified by
name. Lines denoting the OPP acute benchmark values and GLI Tier II calculated acute value
are included.

179


-------
10,000.00

1,000.00

cuo

0)
¦O

X.

O
c

IT!

¦M

3
-Q
C


-------
1.3.4.2 Fenbutatin Oxide Chronic Toxicity Data

Data were gathered by the EPA in 2015, supplemented with the OPP registration review
document for fenbutatin oxide (U.S. EPA 2015). The final chronic fenbutatin oxide dataset
consisted of two NOECs/LOECS for two species across two genera, of which one was an
invertebrate and one was a vertebrate (Table 4).

o\\

MDR

Croup'1

(Ion us

Species

NOIX

(MS/I-)

Loi:c
(MS/I-)

Knilpoinl

Reference

Comment

D

Daphnia

magna

16.00

39.00

Reduced growth and
percent survival in
adults and total
number of young

MRID
40525901;
Hutton 1988

Quantitative

A

Oncorhynchus

mykiss

0.310

0.610

Reduced larval
survival and growth

MRID
40473512;
Hutton 1987

Quantitative

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species

(e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Chronic Benchmark Values

The OPP invertebrate chronic benchmark is 16 |ig/L, which is the NOEC for Daphnia magna.
The OPP fish chronic benchmark is 0.31 |ig/L, which is the NOEC for Oncorhynchus mykiss.

GLI Tier II Chronic Value Calculation

The dataset of quantitative chronic toxicity data for fenbutatin oxide includes data for rainbow
trout (Oncorhynchus mykiss) and water flea (Daphnia magna). Analogous quantitative acute
tests are available for both species; therefore, two ACRs were calculated. The default value of 18
was used for the third ACR. The acute and chronic tests were conducted in different laboratories
using water of different physical characteristics; therefore OPP's approach was used to calculate
the ACRs. OPP's approach involves the use of the lowest (i.e., most sensitive) NOAEC for a
given species in the ACR calculations. The calculated SCV for fenbutatin oxide is 0.060 |ig/L.
Detailed calculations for the SCV are shown below:

SACR = Geometric Mean of the ACRs

SACR = V 1.938# 5.484* 18 = 5.761

181


-------
SCV =	

SACR

0.347

SCV = 5761 = °-060 ^/L

Table 5. Summary and comparison of chronic values for fenbutatin oxide.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

ratio >1 indicates the OPP value is hig

ier than the OW value.

Pesticide

OPP Invertebrate

ALB
(NOAEC) (Year
published, species)

OW Tier II

value
(#of ACRs
filled, magnitude
relative to ALB)

OW Invertebrate-

only HCos
(# of ACRs filled,

magnitude
relative to ALB)

Notes

Fenbutatin Oxide

0.31 ng/L
(2009,

Oncorhynchus
mykiss). Note the
vertebrate ALB is
lower than the
invertebrate ALB (16
Ug/L)

0.06 ng/L
(GLI Tier II; 2
ACRs, 5.IX)

NA

One default ACR of 18
used to derive GLI Tier
II value.

1.3.4.3 Fenbutatin Oxide References

MRID 00113075. Johnson, W. 1973. Acute toxicity of Technical SD14114 to Rainbow Trout
{Oncorhynchus mykiss formerly Scilmo gairdneri). U.S. Fish and Wildlife Service, Fish
Pesticide Research Laboratory; unpublished study. Raw data relayed from W. W.

Johnson (USFWS) to Shell Chemical Com, San Ramon, CA.

MRID 00113076. Johnson, W.; Jones, T. 1971. Static Acute Toxicity of SD 14114 toBluegill.
U.S. Fish and Wildlife Service, Fish-pesticide Research Laboratory; unpublished study;
CDL:098036-I.

MRID 40098001. ECOTOX 6797. Mayer, F. L. J. and Ellersieck, M. R. 1986. Manual of Acute
Toxicity: Interpretation and Data Base for 410 Chemicals and 66 Species of Freshwater Animals.
Resour. Publ. No. 160, U.S. Department of Interior, Fish and Wildlife Services, Washington, DC
505 p.

MRID 40473506. Hutton, D. 1987. Static Acute 96-hour LC50 of Technical Vendex to Rainbow
Trout (Salmo gairdneri): Haskell Laboratory Report No. 327-87: MR 4581-472. Unpublished
study prepared by Haskell Laboratory for Toxicology and Industrial Medicine. 10 p.

MRID 40473509. Hutton, D. 1987. Daphnia magna Static Acute 48-hour EC50 of Technical
Vendex: Haskell Laboratory Report No. 316-87: MR 4581501. Unpublished study prepared by
Dupont Haskell Laboratory for Toxicology and Industrial Medicine. 10 p.

182


-------
MRID 40473512. Hutton, D. 1987. Early Life Stage Toxicity of Technical Vendex to Rainbow
Trout (Salmo gairdneri): Haskell Laboratory Report No. 460-87: MR 4581-472. Unpublished
study prepared by Dupont Haskell Laboratory for Toxicology and Industrial Medicine. 19 p.

MRID 40525901. Hutton, D. 1988. Chronic Toxicity of Technical Vendex to Daphnia magna:
Rept. No. 94-88. Unpublished study prepared by E.I. du Pont de Nemours and Co., Inc. 20 p.

MRID 47910407. Picard, C. R. 2009. Fenbutatin-oxide - 10-Day Toxicity Test Exposing Midge
(Chironomus dilutus) to a Test Substance Applied to Sediment Under Static-Renewal
[Intermittent Flow] Conditions Following OCSPP Draft Guideline 850.1735. Unpublished study
conducted by Springborn Smithers Laboratory, Wareham, MA. Report No.

13845.6122. Sponsored by United Phosphorus, King of Prussia, PA.

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2009. Problem formulation for the environmental fate, ecological risk, endangered
species, and drinking water assessments in support of the registration review of fenbutatin-oxide.
Office of Pesticide Programs. Washington, D.C. September 28, 2009.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

183


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1.3.5 Comparison of Aquatic Life Toxicity Values for Methoxyfenozide: Data Sources
and Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
(CWA) (U.S. EPA 2024) for methoxyfenozide were gathered by OW in 2015 and supplemented
with additional values described in the OPP document on which the benchmark values are based
(U.S. EPA 2013).

1.3.5.1 Methoxyfenozide Acute Toxicity Data

Data were gathered by the OW in 2015 and supplemented with additional values described in the
OPP document on which the benchmark values are based (U.S. EPA 2013). One LCso for
Daphnia magna determined to be "quantitative" data. Two 96-hour LCsos for Oncorhynchus
mykiss and Lepomis macrochirus were classified as qualitative because they were greater than
toxicity values used to fulfill MDR groups, but otherwise considered acceptable. A 120-hour
LCso for the mosquito Anophales gambiae was classified as qualitative because of duration,
uncharacterized source water, feeding during the test, and lack of replicates, but was included in
order to increase the number of invertebrate genera.

The final acute methoxyfenozide dataset consisted of four LCsos for four species representing
four genera, of which two were invertebrate species representing two invertebrate genera (Table
1). The invertebrate GMAVs are listed in Table 2.

184


-------
Table 1. Acute toxicity data of methoxyfenozide to freshwater aquatic organisms.

()\\
MDR

(iroup'1

(Ion us

Species

IX 50/
I X 50
(MS/'-)

S\1 AY

(MS/I-)

(IMAY
(Jili/I)

Reference

Comment

D

Daphnia

magna

3,700

3,700

3,700

MRID 44144411; Holmes and
Swigert. 1993

Quantitative

F

Anaphales

gambiae

248

247.70

247.70

ECOTOX 165535; Morou et al.
2013

Qualitative: Duration; fed during experiment;
tests conducted with unknown water type in
plastic cups; no replicates.

A

Oncorhynchus

mykiss

>4,200

>4,200

>4,200

MRID 44144410; Graves and
Swigert. 1995

Qualitative, greater than endpoint

B

Lepomis

macrochirus

>4,300

>4,300

>4,300

MRID 44144409; Graves and
Swigert. 1995

Qualitative, greater than endpoint

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species (e.g., bluegill, channel catfish,
etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

185


-------
OPP Acute Benchmark Values

The OPP invertebrate acute benchmark is 28.5 |ig/L, which is V2 of the calculated (estimated)
Chironomus riparius acute test value of 57 |ig/L. This acute value for C. riparius was calculated
by multiplying the acute to chronic ratio from studies with Daphnia magna by the NOAEC for
Chironomus riparius (Described in a footnote to Table 4.1 of U.S. EPA 2013). Briefly, The ACR
for D. magna is 18.5. The C. riparius NOAEC (3.1 |ig/L) served as the basis for the OPP
invertebrate chronic benchmark and is used in the acute value calculation. The
estimated/calculated acute value for C. riparius is 57 |ig/L (i.e., 3.1 x 18.5). The OPP fish acute
benchmark is >2,100 |ig/L, which is V2 of the Oncorhynchus mykiss LC50 of >4,200 |ig/L.

GLI Tier II Acute Value Calculation

The acceptable acute dataset for methoxyfenozide fulfills three of the eight MDRs,
corresponding to the use of a Secondary Acute Factor (SAF) of 8. Applying the SAF to the
lowest, most sensitive GMAV (i.e., the only GMAV available, 3,700 |ig/L for water flea
(Daphnia magna)), the calculated Secondary Acute Value (SAV) is 462.5 |ig/L. The Secondary
Maximum Criterion (SMC), which is calculated as half the SAV, is 231.3 |ig/L. Detailed
calculations for the SMC are shown below:

Lowest GMAV

3,700

SAV = —— = 462.5 |xg/L
SAV

SMC =	

2

462.5

SMC = —= 231.3 |xg/L

Genus-Level Invertebrate Acute HC05

No genus-level invertebrate Acute HC05 could be calculated following USEPA (1985)
methodology because there were only two invertebrate genera (Table 2).

Table 2. Methoxyfenozide invertebrate SMAVs and GMAVs (ng/L).

(iOIIIIS

Species

SMAY

(;\1AY

CMAY Kiink

Daphnia

magna

3,700

3,700

2

Anaphales

gambiae

247.7

247.7

1

Note: The A. gambiae GMAV is based on data classified as qualitative that was included to increase the number of
invertebrate genera.

186


-------
Table 3. Summary and comparison of acute values for methoxyfenozide.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a
ratio >1 indicates the OPP value is higher than the OW value.

Pesticide

OPP

Invertebrate
ALB
(lowest
LCso/2) (Year
published,
species)

OW GLI Tier II
value
(# of MDRs

filled,
magnitude
relative to ALB)

OW Genus
Level
Invertebrate-
only HCos/2

Notes

Methoxyfenozide
(Insect Growth
Regulator;
Diacylhydrazine)

28.5 ng/L
(2013;
Chironomus
riparius)

231.3 ng/L
(3 MDRs filled,
0.0043X)

NA

(2 genera)

FIFRA ALB value was calculated
by multiplying the acute-to-chronic
ratio from studies with I), magna by
the NOAEC for C. riparius. The C.
riparius NOAEC (3.1 |ig/L) serves
as the basis for the FIFRA ALB
chronic benchmark.

The Tier II value is approximately
10 times larger than the FIFRA
ALB because it is based on the
GMAV for Daphnia, which is 74
times larger than the calculated test
value for C. riparius (57 ug/L).

Figure 1 shows a genus-level sensitivity distribution for the methoxyfenozide dataset. Major
taxonomic groups are delineated by different symbols, and invertebrate genera are identified by
name. Lines denoting the OPP acute benchmark values and the GLI Tier II calculated value are
included.

187


-------
10,000.0

1,000.0

w>
3.

01

N

o
c

£
>
X

o
c

0

-C
+-»

01

100.0

10.0

1.0

•

Arthropod

o

Arthropod (Qualitative)

¦

Salmonid Fish

~

Other Fish



OPP Invert. Benchmark

	

OPP Fish Benchmark



GLI Tier II Acute Value

0.0

0.1

0.2

• Daphnia

Anaphales

~

OPP Fish Benchmark = 2,100 pg/L

GLI Tier II Acute Value = 231.3 pg/L

OPP Invertebrate Benchmark = 28.5 pg/L

Genus-level Invertebrate HC05/2 could not be calculated

0.3	0.4	0.5	0.6	0.7	0.8	0.9	1.0

Sensitivity Centile

Figure 1. Methoxyfenozide genus-level acute SD.

Symbols represent GMAVs calculated using all available data from the 2015 EPA literature search, supplemented with the OPP
registration review for methoxyfenozide (U.S. EPA 2013).

188


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1.3.5.2 Methoxyfenozide Chronic Toxicity Data

Chronic methoxyfenozide data were gathered by the OW in 2015 and supplemented with
additional values described in the OPP document on which the benchmark values are based (U.S.
EPA 2013). The final chronic methoxyfenozide dataset consisted of three NOECs/LOECS for
three species across three genera, of which two were invertebrate genera and one was a
vertebrate genus (Table 4).

Table 4. Chronic toxicity data of methoxyfenozide to freshwater aquatic organisms

OW
MIJR

(Irniip'1

(ion lis

Spocios

NOEC
(Mii/U

LOIX

(MS/'-)

Knilpoinl

Rol'oronco

Common!

D

Daphnia

magna

200.0

390.0

Survival

MRID 446177-14;
Zelinkaetal. 1993

Quantitative

F

Chironomus

riparius

3.1

6.3

Delayed emergence
and development

MRID 450328-01;
Kolk 2000

Supplemental
(non-guideline)

B

Pimephales

promelas

530

1,000

Survival

MRID 446177-16;
Rhodes and
Hurshman 1998

Acceptable

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species

(e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Chronic Benchmark Values

The OPP invertebrate chronic benchmark is 3.1 |ig/L, which is the NOEC for Chironomus
riparius.

The OPP fish chronic benchmark is 530 |ig/L, which is the NOEC for Pimephalespromelas.
GLI Tier II Chronic Value Calculation

Paired quantitative chronic and acute toxicity data for methoxyfenozide were available for water
flea (Daphnia magna), allowing for the calculation of one ACR. The remaining two ACRs were
fulfilled by the default value of 18. The acute and chronic tests were conducted in different
laboratories using water of different physical characteristics; therefore, OPP's approach was used
to calculate the ACR. OPP's approach involves the use of the NOAEC) in the calculations. The
calculated SCV for methoxyfenozide is 25.46 |ig/L.

Detailed calculations for the SCV are shown below:

SACR = Geometric Mean of the ACRs

SACR = V18.50* 18* 18 = 18.17

189


-------
SCV =	

SACR

462.5

SCV = ——=25 A6\ig/L
18.17

Table 5. Summary and comparison of chronic values for methoxyfenozide

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for

each value comparison. A ratio <1 indicates the OPP va

ue is lower than the OW value.

Pesticide

OPP Invertebrate

ALB
(NOAEC) (Year
published, species)

OW Tier II

value
(#of ACRs
filled, magnitude
relative to ALB)

OW Invertebrate-
only ALC (FCV)
(# of ACRs filled,

magnitude
relative to ALB)

Notes

Methoxyfenozide

3.1 ng/L

(2019, Chironomus
riparius)

25.5 ng/L
(GLI Tier II; 1
ACR, 0.25X)

NA

Two default ACRs of 18
used to derive GLI Tier
II value.

1.3.5.3 Methoxyfenozide References

ECOTOX 165535. Morou, E., M. Lirakis, N. Pavlidi, M. Zotti, Y. Nakagawa, G. Smagghe, J.
Vontas, and L. Swevers. 2013. A New Dibenzoylhydrazine with Insecticidal Activity Against
Anopheles Mosquito Larvae. PestManag. Sci.69(7): 827-833.

MRID 44144409. Graves, W., and Swigert, J. 1995. RH-112,485 Technical: A 96-Hour Flow-
Through Acute Toxicity Test with the Bluegill (Lepomis macrochirus): Final Report: Lab Project
Number: 129A-125: 95RC-0026: 129/013195/BLU-96H2/CHP83. Unpublished study prepared
byWildlife International Ltd. 90 p.

MRID 44144410. Graves, W., and Swigert, J. 1995. RH-112,485 Technical: A 96-Hour Flow-
Through Acute Toxicity Test with the Rainbow Trout (Oncorhynchus mykiss): Final Report: Lab
Project Number: 129A-124: 95RC-0025: 129/013195/RBT-96H2/CHP84. Unpublished study
prepared by Wildlife International Ltd. 90 p.

MRID 44144411. Holmes, C., and Swigert, J. 1993. RH-112,485 Technical: A 48-Hour Flow-
Through Acute Toxicity Test with the Cladoceran (Daphnia magna): Final Report: Lab Project
Number: 129A- 112B: 92RC-0028: 129/032692/DAP-48H2/CHP38. Unpublished study
prepared by Wildlife International Ltd. 93 p.

MRID 446177-14. Zelinka, E. Holmes, C., Martin, K. et al. 1993. RH-112,485 Technical: A
Flow-Through Life-Cycle Toxicity Test With the Cladoceran (Daphnia magna): Amended Final
Report: Lab Project Number: 129A-113B: 92RC-0029: 129/032692/DAP-LC2/CHP38.
Unpublished study prepared by Wildlife International Ltd. 108 p.

MRID 446177-16. Rhodes, J., andHurshman, B. 1998. Full Life-Cycle Toxicity of RH-112,485
Technical to the Fathead Minnow (Pimephales promelas) Under Flow-Through Conditions: Lab
Project Number: 43701: 96RC-0184: 96P-184. Unpublished study prepared by ABC
Laboratories. 1246 p.

190


-------
MRID 450328-01. Kolk, J. 2000 RH-2485 Technical: Chronic Effects on Midge Larvae
(Chironomus riparius)in Water/Sediment System: Final Report: Lab Project Number: 99P-001:
1007.051.173: 99RC-0001. Unpublished study prepared by Springborn Labs. (Europe) AG. 119
P-

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2013. Registration review. Preliminary problem formulation for environmental fate,
ecological risk, endangered species, and human health drinking water exposure assessments for
methoxyfenozide. Office of Pesticide Programs. Washington, D.C. April 25, 2013.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

191


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1.3.6 Comparison of Aquatic Life Toxicity Values for Norflurazon: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
(CWA) (U.S. EPA 2024) for norflurazon were gathered by OW in 2015. Additionally, three OPP
documents (U.S. EPA 2008, 2012, 2017) on which the benchmark values are based also provided
data. The OPP invertebrate and fish benchmark values were the same in all three documents.

1.3.6.1 Norflurazon Acute Toxicity Data

Acute norflurazon data were gathered by OW in 2015. Additionally, three OPP documents (U.S.
EPA 2008, 2012, 2017) on which the benchmark values are based also provided data. (See Table
1.) The OPP invertebrate and fish benchmark values were the same in all three documents
examined. Two LCsos were classified as "quantitative" data and one 96-hour LCso for Daphnia
magna was classified as qualitative because of its duration and because it was a greater than
value. This test was included to fulfill a MDR group, and because it serves as the basis for the
OPP invertebrate benchmark value.

The final acute norflurazon dataset consisted of three LCsos for three species representing three
genera, of which one was an invertebrate species. The invertebrate GMAV for Daphnia is listed
in Table 2.

Table 1. Acute toxicity data of norflurazon to freshwater aquatic organisms.

OW
M l)K

(iroiip'1

(ionus

Species

IX 50/
I X 50
(MS/'-)

S\1 AY

(M8/U

(IMAY

(MS/'-)

Reference

Comment

D

Daphnia

magna

>15,000

>15,000

>15,000

MRID
00035709;
Vilkas and
Browne. 1980

Qualitative,
greater than
value,
duration

A

Oncorhynchus

mykiss

8,100

8,100

8,100

MRID

00087863; Stall
etal. 1981

Quantitative

B

Lepomis

macrochirus

16,300

16,300

16,300

MRID 0087862;
Stall etal. 1981

Quantitative

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important

warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Acute Benchmark Values

The OPP invertebrate acute benchmark is >7,500 |ig/L, which is '/2 of the Daphnia magna test
value of >15,000 |ig/L.

192


-------
The OPP fish acute benchmark is 4,050 |ig/L, which is V2 of the Oncorhynchus mykiss LC50 of
8,100 |ig/L.

GLI Tier II Acute Value Calculation

The acceptable acute dataset for norflurazon fulfills three MDRs, corresponding to the use of a
SAF of 8. Applying the SAF to the lowest, most sensitive GMAV (i.e., 8,100 |ig/L for rainbow
trout (Oncorhynchus mykiss), the calculated SAV is 1,012.5 |ig/L. The SMC, which is calculated
as half the SAV, is 506.3 |ig/L. Detailed calculations for the SMC are shown below:

Lowest GMAV

8,100

SAV = —— = 1,012.5 |xg/L
SAV

SMC =	

2

1,012.5

SMC = —-— = 506.3 |xg/L

Genus-Level Invertebrate-only Acute HC05

No genus-level invertebrate acute HC05 could be calculated using the USEPA (1985)
methodology because there was only one invertebrate genus (Table 2).

Table 2. Norflurazon invertebrate SMAV and GMAV (^g/L).

Genus

Species

SMAV

GMAV

GMAV Rank

Daphnia

magna

>15,000

>15,000

1

Table 3. Summary and comparison of acute values for norflurazon. Magnitude relative to
ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for each value
comparison. A ratio >1 indicates the OPP value is higher than the OW value.	

Pesticide

OPP Most
Sensitive ALB
(lowest LCso/2)
(Year published,
species)

OW GLI Tier II

value
(# of MDRs filled,

magnitude
relative to ALB)

OW Genus-

level
Invertebrate-
only HCos/2

Notes

Norflurazon

(Pyridazine

Herbicide)

4,050 (ig/L
(2023;

Oncorhynchus
mykiss)

506.3 ng/L 3
MDRs filled, 8X)

NA

(1 genus)

The lowest OPP ALB is for
nonvascular plants (6.03 |ig/L).
but the GLI Tier II value is based
on O. mykiss so the vertebrate
ALB is used in this comparison.

Figure 1 shows a genus-level sensitivity distribution for the norflurazon dataset. Major
taxonomic groups are delineated by different symbols, and invertebrate genera are identified by

193


-------
name. Lines denoting the OPP acute benchmark values and GLI Tier II calculated values are
included.

194


-------
100,000

10,000

GO
3-
c
o

N

ro

1,000

•

Arthropod (Qualitative)

¦

Salmonid Fish

~

Other Fish



OPP Invert. Benchmark

	

OPP Fish Benchmark



GLI Tier II Acute Value

• Daphnia

~

OPP Invertebrate Benchmark = >7,500 pg/L
OPP Fish Bench ma rk = 4,050 pg/L

GLI Tier II Acute Value = 506.3 ng/L

100

Genus-level Invertebrate HC05/2 could not be calculated

0.0

0.1

0.2

0.3

0.4	0.5	0.6	0.7	0.8	0.9	1.0

Sensitivity Centile

Figure 1. Norflurazon genus-level SD.

Symbols represent GMAVs calculated using all available data from the 2015 EPA literature search, supplemented the OPP registration
review document for norflurazon (U.S. EPA 2017).

195


-------
1.3.6.2 Norflurazon Chronic Toxicity Data

Chronic norflurazon data were gathered by OW in 2015. Additionally, three OPP documents
(U.S. EPA 2008, 2012, 2017) on which the benchmark values are based also provided data.

The final chronic norflurazon dataset consisted of three NOECs/LOECS for three species across
three genera, of which one was an invertebrate genus and two were vertebrate genera (Table 4).

Table 4.

Chronic toxicit

y data of norflurazon to freshwater aquatic organisms

OW
M l)K
(Iroup1

(ion lis

Species

NOEC
(MB/'-)

I.OIX

Knilpoinl

Reference

D

1 );iphni;i

mauiia

1 .(ion

2.<><><)

Reduced iiuiiihei'of

oil's pi'niK

Nlkll) uu| IX()4<>.

LeBlanc 1982

A

Oncorhynchus

mykiss

770

1,500

Growth

MRID 0018048;
LeBlanc 1982

B

Pimephales

promelas

1,100

2,100

Growth

MRID 00118047;
LeBlanc 1982

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species

(e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Chronic Benchmark Values

The OPP invertebrate chronic benchmark is 1,000 |ig/L, which is the NOEC for Daphnia magna.
The OPP fish chronic benchmark is 770 |ig/L, which is the NOEC for Oncorhynchus mykiss.

GLI Tier II Chronic Value Calculation

Paired quantitative chronic and acute toxicity data for norflurazon were not available for
freshwater aquatic organisms; therefore, each of the three ACRs were fulfilled by the default
value of 18. The calculated SCV for norflurazon is 56.25 |ig/L.

Detailed calculations for the SCV are shown below:

= Geometric Mean of the ACRs

= Vl8 * 18 * 18 = 18

SACR
1,012.5

—- = 56.25 [ig/L

SACR :
SACR :

SCV =
SCV =

196


-------
Table 5. Summary and comparison of chronic values for norflurazon. Magnitude relative to
ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for each value
comparison. A ratio >1 indicates the OPP value is higher than the OW value.	

Pesticide

Most Sensitive

OPP ALB
(NOAEC) (Year
published, species)

OW Tier II

value
(#of ACRs
filled, magnitude
relative to ALB)

OW

Invertebrate-only

HCos
(# of ACRs filled,

magnitude
relative to ALB)

Notes

Norflurazon

770 ng/L
(2023,

Oncorhynchus
mykiss).

56.3 ng/L
(GLI Tier II; 0
measured-data
based ACRs,
14X)

NA

Three default ACRs of
18 used to derive GLI
Tier II value.

Note the lowest ALB is
for nonvascular plants
(5.33 |ig/L). but the GLI
Tier II value is based on
O. mykiss so the
vertebrate ALB is used
in this comparison.

1.3.6.3 Norflurazon References

MRID 00035709. Vilkas, A.G.; Browne, A.M. 1980. The Acute Toxicity ofNorflurazon (99.4
Percent Active Ingredient) to the Water Flea, Daphnia magna Straus: UCCES Project No. 11506-
16-04. (Unpublished study including letter dated May 20, 1980 from R.J. McCormack to R.E.
Stoll, received Jun 5, 1980 under 11273- 19; prepared by Union Carbide Corp., submitted by
Sandoz, Inc.—Crop Protection, San Diego, Calif.; CDL:242619-A).

MRID 00087863. Stoll, R.E.; LeBlanc, G.A.; Sousa, J.V. 1981. Acute LCI5W' Toxic-ity Study
in the Rainbow Trout on Nortlurazon: EG&G Bionomics No. BW 31-7-899; Sandoz Project T -
163 7. (Unpublished study received Dec 18, 1981 under 11273-10; prepared in cooperation with
EG & G, Bionomics, submitted by Sandoz, Inc.—Crop Protec-tion, San Diego, Calif.;
CDL:246433-A).

MRID 00118047. LeBlanc, G. (1982) Early Life Stage Toxicity Study in the Fathead Minnow on
Norflurazon: Report #BW-82-5-l 166; Sandoz Project T- 1767. (Unpublished study received Nov
15, 1982 under 11273-13; prepared by EG & G, Bionomics, submitted by Sandoz, Inc., Crop
Protection, San Diego, CA; CDL:248828-A).

MRID 00118048. LeBlanc, G. (1982) Early-life Stage Toxicity Study in the Rainbow Trout on
Norflurazon: Report #BW-82-5-l 165; Sandoz Project T- 1733. (Unpublished study received Nov
15, 1982 under 11273-13; prepared by EG& G, Bionomics, submitted by Sandoz, Inc., Crop
Protection, San Diego, CA; CDL:248829-A).

MRID 00118049. LeBlanc, G. (1982) 21-day Chronic Toxicity Test in the Daphnia magna:
Bionomics Report #BW-82-5-l 169; Sandoz Project T-1768. (Unpublished study received Nov
15, 1982 under 11273-13; pre- pared by EG & G, Bionomics, submitted by Sandoz, Inc., Crop
Pro- tection, San Diego, CA; CDL:248830-A).

197


-------
MRID 0087862. Stoll, R.E.; LeBlanc, G.A.; Sousa, J.V. 1981. Acute LCI5QI' Toxici-ty Study in
the Bluegill Sunfish on Nortlurazon: EG&G Bionomics No. BW 81-7 -897; Sandoz Project T -
163 8. (Unpublished study received Dec 18, 1981 under 11273-10; prepared in cooperation with
EG & G, Bionomics, submitted by Sandoz, Inc.—Crop Protec-tion, San Diego, Calif.;
CDL:246434-A).

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2008. Risks of norflurazon use to federally threatened California red-legged frog
(Rana aurora draytonii). Pesticides effects determination. Office of Pesticide Programs.
Washington, D.C. February 18, 2008.

U.S. EPA. 2012. Registration review. Preliminary problem formulation for environmental fate
and ecological risk, endangered species, and drinking water assessments for norflurazon. Office
of Pesticide Programs. Washington, D.C. August 9, 2012.

U.S. EPA. 2017. Registration review: Preliminary risk assessment for environmental fate and
ecological risk for norflurazon. Office of Pesticide Programs. Washington, D.C. September 28,
2017.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

198


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1.3.7 Comparison of Aquatic Life Toxicity Values for Propargite: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
(CWA) (U.S. EPA 2024) for propargite were gathered by OW in 2015 and supplemented with
data from the OPP propargite document on which the benchmark values are based (U.S. EPA
2014).

1.3.7.1 Propargite Acute Toxicity Data

Acute propargite data were gathered by OW in 2015 and supplemented with data from the OPP
document on which the benchmark values are based (U.S. EPA 2014; See Table 1). Five LCsos
across three species representing three genera were classified as "quantitative" data; Three LCsos
(one each for Daphnia magna, Lepomis macrochirus, and Oncorhynchus mykiss; the three
species represented with quantitative test data) were classified as acceptable in U.S. EPA (2014).
One 24-hour LCsos for the yellow fever mosquito Aedes aegypti was classified as qualitative
because of duration, feeding during the test, unknown control mortality, and lack of information
in source or control water, but included here to increase the number of invertebrate genera.

The final acute propargite dataset consisted of nine LCsos for four species representing four
genera, of which two were invertebrate species representing two invertebrate genera. The
invertebrate GMAVs are listed in Table 2.

Table 1. Acute toxicity data of propargite to freshwater aquatic organisms.

OW





I X 50/

S\1 AY

(M8/U

(IMAY

(MS/'-)



MIJR

(iroup'1

(ion us

Species

l-X 50
(MB/1-)

Reference

D

Daphnia

magna

91





ECOTOX 344; U.S. Environmental
Protection Agency, and Office of
Pesticide Programs. 2013

D

Daphnia

magna

14

45.64

45.64

MRID 46015901; Knight and Allan.
2002

D

Daphnia

magna

74.6





MRID 43759002; Davis. 1995

F

Aedes

aegypti

780.0

780.0

780.0

ECOTOX 116328; Pridgeon et al.
2009

A

Oncorhynchus

mykiss

118

89.86

89.86

ECOTOX 344; U.S. Environmental
Protection Agency, and Office of
Pesticide Programs. 2013

A

Oncorhynchus

mykiss

43





MRID 41458301; Sousa. 1990

A

Oncorhynchus

mykiss

143





MRID 43759001; Davis. 1995

B

Lepomis

macrochirus

167

116.3

116.3

ECOTOX 344; U.S. Environmental
Protection Agency, and Office of
Pesticide Programs. 2013

B

Lepomis

macrochirus

81





MRID 46073301; Knight and Allan.
2002

a MDR Groups - Freshwater:

199


-------
A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important
warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian,
etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Acute Benchmark Values

The OPP invertebrate acute benchmark is 7 |ig/L, which is V2 of the Daphnia magna LC50 of 14
Hg/L.

The OPP fish acute benchmark is 40.5 |ig/L, which is V2 of the Lepomis macrochirus LC50 of 81
Hg/L.

GLI Tier II Acute Value Calculation

The acceptable acute dataset for propargite fulfills three of the eight MDRs, corresponding to the
use of a SAF of 8. Applying the SAF to the lowest, most sensitive GMAV (i.e., 35.69 |ig/L for
water flea (Daphnia magna), the calculated SAV is 4.462 |ig/L. The SMC, which is calculated as
half the SAV, is 2.231 |ig/L.

Detailed calculations for the SMC are shown below:

Lowest GMAV

35.69

SAV = —— = 4.462 |xg/L
SAV

SMC= —

4.462

SMC = —— = 2.2311xg/L

Genus-Level Invertebrate Acute HC05

No genus-level invertebrate acute HC05 could be calculated using the USEPA (1985)
methodology because there were only two invertebrate genera (Table 2).

Table 2. Propargite invertebrate SMAVs and GMAVs (iig/L).

(ion us

Species

S\1 AY

(IMAY

CMAY kiink

Aedes

aezypd

"SU.U

"SU.U

:

Daphnia

magna

45.64

45.64

1

200


-------
Table 3. Summary and comparison of chronic values for propargite.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

ratio >1 indicates t

le OPP value is higher than the OW value.

Pesticide

OPP Invertebrate ALB
(lowest LCso/2) (Year
published, species)

OW GLI Tier II value

(# of MDRs filled,
magnitude relative to
ALB)

OW Genus-level
Invertebrate-only

HCos/2

Propargite
(OS Miticide)

7 (ig/L

(2021; Daphnia magna)

2.231 jig/L (3 MDRs
filled, 3.IX)

NA

(1 genus)

Figure 1 shows a genus-level sensitivity distribution for the propargite dataset. Major taxonomic
groups are delineated by different symbols, and invertebrate genera are identified by name. Lines
denoting the OPP acute benchmark values and GLI Tier II calculated value are included.

201


-------
1,000.00

100.00 -

ClD

3.

QJ

¦M

bfl

i_

TO
CL

O

10.00 -

• Arthropod
O Arthropod (Qualitative)
¦ Salmonid Fish
~ Other Fish

	OPP Invert. Benchmark

•- OPP Fish Benchmark
	GLI Tier II Acute Value

• Daphnia

O Aedes

OPP Fish Benchmark = 40.5 ng/L

OPP Invertebrate Benchmark = 7 |ig/L

GLI Tier II Acute Value = 2.231 (ig/L

1.00

Genus-level Invertebrate FIC05/2 could not be calculated

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

Sensitivity Centile

Figure 1. Propargite genus-level acute SD.

Symbols represent GMAVs calculated using all available data from obtained from the EPA's 2015 literature search, supplemented the
OPP registration review document for propargite (U.S. EPA 2014).

202


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1.3.7.2 Propargite Chronic Toxicity Data

Chronic data for propargite were gathered by OW in 2015 and supplemented with data from the
OPP propargite document on which the benchmark values are based (U.S. EPA 2014).

The final chronic propargite dataset consisted of three NOECs/LOECS for three species across
three genera, of which one was an invertebrate genus and two were vertebrate genera (Table 4).

Table 4. Chronic toxicity data of propargite to freshwater aquatic organisms

OW
MIJR

(iioup'

(Ion us

Species

\oi:c

(MS/'-)

I.OIX

(MB/I-)

Kiulpoinl

Reference

Comment

D

Daphnia

magna

9.000

14.00

Growth
(length)

MRID 0126738;
Forbis et al. 1983 /
MRID 00142594;
Forbis and
Franklin. 1984

Quantitative

A

Oncorhynchus

mykiss

14

21

Survival and
growth
(weight)

MRID 41458301;
Sousa 1990

Supplemental

B

Pimephales

promelas

16

28

Survival and
growth
(weight)

MRID 00126739/
00132605; Forbis
et al. 1983

Acceptable

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species

(e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Chronic Benchmark Values

The OPP invertebrate chronic benchmark is 9 |ig/L, which is the NOEC for Daphnia magna. The
OPP fish chronic benchmark is 16 |ig/L, which is the NOEC for Pimephalespromelas.

GLI Tier II Chronic Value Calculation

Paired quantitative chronic and acute toxicity data for propargite were available for water flea
(Daphnia magna), allowing for the calculation of one ACR. The remaining two ACRs were
fulfilled by the default value of 18. The acute and chronic tests were conducted in different
laboratories using water of different physical characteristics; therefore, OPP's approach was used
to calculate the ACR. OPP's approach involves the use of the NOAEC in the calculations. The
calculated SCV for propargite is 0.561 |ig/L.

Detailed calculations for the SCV are shown below:

SACR = Geometric Mean of the ACRs

SACR = Vl.556 * 18 * 18 = 7.958

203


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SCV =	

SACR

4.462

5CK = JI^q = °"561 M/L

Table 5. Summary and comparison of chronic values for propargite.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio >1 indicates the OPP value is higher than the OW value.	

Pesticide

OPP Invertebrate

ALB
(NOAEC) (Year
published, species)

OW Tier II

value
(#of ACRs
filled, magnitude
relative to ALB)

OW Invertebrate-

only HCos
(# of ACRs filled,

magnitude
relative to ALB)

Notes

Propargite

9 (ig/L

(2021, Daphnia
magna)

0.56 ng/L
(GLI Tier II; 1
ACR, 16X)

NA

Two default ACRs of 18
used to derive GLI Tier
II value.

Note the lowest ALB is
for nonvascular plants
(1.27 |ig/L). but the GLI
Tier II value is based on
D. magna so the
invertebrate ALB is used
in this comparison.

1.3.7.3 Propargite References

ECOTOX 116328. Pridgeon, J.W., J.J. Becnel, G.G. Clark, and K.J. Linthicum. 2009. A High-
Throughput Screening Method to Identify Potential Pesticides for Mosquito Control. J. Med.
Entomol.46(2): 335-341.

ECOTOX 344. U.S. Environmental Protection Agency, and Office of Pesticide Programs. 2013.
Pesticide Ecotoxicity Database (Formerly: Environmental Effects Database (EEDB))
Environmental Fate and Effects Division, U.S.EPA, Washington, D.C.

MRJD 00126739 / 00123605. Forbis, A.; Franklin, L.; Boudreau, P.; et al. 1983. Early Life Stage
Toxicity of Omite to Fathead Minnows in a Flow-through System: Early Life Stage Final Report
#29634. (Unpublished study received Apr 8, 1983 under 400-104; prepared by Analytical Bio-
Chemistry Laboratories, Inc., submitted by Uniroyal Chemi- cal, Bethany, CT; CDL:249886-A)

MRID 00142594. Forbis, A.; Franklin, L. 1984. Chronic Toxicity of Omite to Daphnia magna
under Flow-through Test Conditions: ABC Final Re- port #31133. Unpublished study prepared
by Analytical Bio-Chemistry Laboratories, Inc. 172 p.U.S. EPA. 2015. Tier II aquatic life
community benchmarks for propargite. Office of Water and Office of Pesticide Programs.
Washington, D.C. March 2015.

204


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MRID 0126738. Forbis, A.; Franklin, L.; Boudreau, P.; et al. 1983. Early Life Stage Toxicity of
Omite to Fathead Minnows in a Flow-through System: Early Life Stage Final Report #29634.
(Unpublished study received Apr 8, 1983 under 400-104; prepared by Analytical Bio-Chemistry
Laboratories, Inc., submitted by Uniroyal Chemical, Bethany, CT; CDL:249886-A).

MRID 41458301. Sousa, J. 1990. Omite Technical: Acute Toxicity to Rainbow Trout
(Oncorhynchus mykiss): Lab Project Number: 89-6-3010: 41.0289. 6117.108. Unpublished
study prepared by Springborn Labs., Inc. 41 p.

MRID 43759001. Davis, J. 1995. Comite: Acute Toxicity to Rainbow Trout (Oncorhynchus
mykiss) Under Flow-Through Test Conditions: Lab Project Number: J9501010B. Unpublished
study prepared by Toxikon Environmental Sciences. 64 p.

MRID 43759002. Davis, J. 1995. Comite: Acute Toxicity to Water Flea (Daphnia magna) Under
Flow-Through Test Conditions: Lab Project Number: J9501010C. Unpublished study prepared
by Toxikon Environmental Sciences. 64 p.

MRID 46015901. Knight, B.; Allan, J. 2002. Determination of Acute Toxicity (EC50) of
Propargite to Daphnia magna (48 h, Continous-Flow). Project Number: 20632, 800052.
Unpublished study prepared by Inveresk Research International. 54 p.

MRID 46073301. Knight, B.; Allan, J. 2002. Determination of Acute Toxicity (LC50) of
Propargite to Bluegill Sunfish (96 h, Continuous-Flow). Project Number: 20480, 800031.
Unpublished study prepared by Inveresk Research International. 52 p.

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2014. Registration review. Problem formulation (for) propargite. Office of Pesticide
Programs. Washington, D.C. May 5, 2014.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

205


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1.3.8 Comparison of Aquatic Life Toxicity Values for Pyridaben: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
('CWA) (U.S. EPA 2024) for pyridaben were gathered by the OW in 2015, supplemented with
additional values from the OPP document on which the benchmark values are based (U.S. EPA
2010).

1.3.8.1 Pyridaben Acute Toxicity Data

Acute pyridaben toxicity data were gathered by the OW in 2015 and supplemented with
additional values from the OPP document on which the benchmark values are based (U.S. EPA
2010; See Table 1). Four LCsos across three species and three genera were identified and
classified as "quantitative" data. Four LCsos (two for Oncorhynchus mykiss, one for Daphnia
magna, and one for Pimephales) were classified as acceptable in Appendix C of U.S. EPA
(2010).

The final acute pyridaben dataset consisted of eight LCsos for four species representing four
genera, of which one was an invertebrate species. The invertebrate GMAV is listed in Table 2.

Table 1. Acute toxicity data of pyridaben to freshwater aquatic organisms.

OW





l .( 50/

S\1 AY

(MB/'-)

(IMAY

(^g/L)



M l)K

(iroup'

(ionus

Species

IX 50
(Mli/U

Reference

D

Daphnia

magna

0.530

0.7353

0.7353

MRID 42680111; Willis and Wilson.
1987

D

Daphnia

magna

1.02

MRID 43680404; Graves and
Swigert. 1993

A

Oncorhynchus

mykiss

0.720





MRID 43680402; Ward. 1994

A

Oncorhynchus

mykiss

2.3

1.743

1.743

MRID 42680109; Willis and Wilson.
1987

A

Oncorhynchus

mykiss

3.2





MRID 43680403; Bootman et al.
1989

B

Lepomis

macrochirus

3.430

2.940

2.940

MRID 43680401; Ward. 1994

B

Lepomis

macrochirus

2.520

MRID 42680110; Willis. 1988

C

Pimephales

promelas

2.30

2.3

2.3

MRID 43792106; Rhodes et al. 1995

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important
warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

206


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OPP Acute Benchmark Values

The OPP invertebrate acute benchmark is 0.265 |ig/L, which is V2 of the Daphnia magna LC50 of
0.530 |ig/L.

The OPP fish acute benchmark is 0.36 |ig/L, which is V2 of the Oncorhynchus mykiss LC50 of
0.72 |ig/L.

GLI Tier II Acute Value Calculation

The acceptable acute dataset for pyridaben fulfills three OW MDRs, corresponding to the use of
a SAF of 8. Applying the SAF to the lowest, most sensitive GMAV (i.e., 0.530 |ig/L for water
flea (Daphnia magna), the calculated SAV is 0.066 |ig/L. The SMC, which is calculated as half
the SAV, is 0.033 |ig/L.

Detailed calculations for the SMC are shown below:

Lowest GMAV

0.530

SAV = —— = 0.066 |xg/L
SAV

SMC= —

0.066

SMC = —— = 0.033 |xg/L

Genus-Level Invertebrate-only Acute HC05

No genus-level invertebrate acute HC05 could be calculated using the USEPA (1985)
methodology because there was only one invertebrate genus (Table 2).

Table 2. Pyridaben invertebrate SMAV and GMAV (iig/L).

Genus

Species

SMAV

GMAV

GMAV Rank

Daphnia

magna

0.7353

0.7353

1

Table 3. Summary and comparison of acute values for pyridaben.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison A ratio >1 indicates the OPP value is higher than the OW value.	

Pesticide

OPP Invertebrate
ALB

(lowest LCso/2) (Year
published, species)

OW GLI Tier II value
(# of MDRs filled,
magnitude relative to ALB)

OW Genus-level
Invertebrate-only ALC

(FAV/2) "

Pyridaben

(Nicotinamide Inhibitor)

0.265 ng/L
(2023; Daphnia
magna)

0.033 (ig/L (3 MDRs filled,
8X)

NA

(1 genus)

207


-------
Figure 1 shows a genus-level sensitivity distribution for the pyridaben dataset. Major taxonomic
groups are delineated by different symbols, and invertebrate genera are identified by name. Lines
denoting the OPP acute benchmark values and GLI Tier II calculated acute value are included.

208


-------
100.00

10.00

ho

3
c

01
-Q
ro
;u
"C
>•
Q.

1.00

0.10

•

Arthropod

¦

Salmonid Fish

~

Other Fish



OPP Invert. Benchmark

	

OPP Fish Benchmark



GLI Tier II Acute Value

~

~

• Daphnia

OPP Fish Benchmark = 0.36 pg/L
OPP Invertebrate Benchmark = 0.265 ^ig/L

GLI Tier II Acute Value = 0.033 pg/L

Genus-level Invertebrate HC05/2 could not be calculated

0.01

0.0

0.1

0.2

0.3

0.4	0.5	0.6

Sensitivity Centile

0.7

0.9

1.0

Figure 1. Pyridaben genus-level acute SD.

Symbols represent GMAVs calculated using all available data from EPA's 2015 literature search supplemented the OPP registration
review document for pyridaben (U.S. EPA 2010).

209


-------
1.3.8.2 Pyridaben Chronic Toxicity Data

Chronic pyridaben toxicity data were gathered by the OW in 2015 and supplemented with
additional values from the OPP document on which the benchmark values are based (U.S. EPA
2010). The final chronic pyridaben dataset consisted of two NOECs/LOECS for two species
across two genera, of which one was an invertebrate and one was a vertebrate (Table 4).

Table

. Chronic toxicity data of pyridaben to freshwater aqual

tic organisms.

OW
MDR

(iioup'

(Ion us

Species

\oi:c

(fiii/i)

I.OIX

(MU/I-)

Knilpoint

Reference

Comment

D

Daphnia

magna

0.044

0.086

Delayed time to
reproduction

MRID 43680408;
Drottar and Swigert
1994

Quantitative

B

Pimephales

promelas

0.277

0.555

Growth of F0 and
F1 generation and
F1 survival

MRID 43792106;
Rhodes etal. 1995

Acceptable

a MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important warmwater species

(e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Chronic Benchmark Values

The OPP invertebrate chronic benchmark is 0.044 |ig/L, which is the NOEC for Daphnia magna.

The OPP fish chronic benchmark is 0.087 |ig/L, which is the estimated NOEC for Oncorhynchus
mykiss. The 0. mykiss NOEC was estimated using P. promelas data. Acute and chronic toxicity
data are available fori5, promelas exposed to pyridaben (96-h LC50 = 2.3 (J,g/L; NOAEC =
0.277 (J,g/L; ACR = 8.3; MRID 43792106). Because the rainbow trout is more sensitive on an
acute exposure basis, the ACR is used to derive a NOAEC for the rainbow trout (0.72 8.3 =
0.0867 |ig/L)

GLI Tier II Chronic Value Calculation

Paired quantitative chronic and acute toxicity data for pyridaben were available for water flea
(Daphnia magna), allowing for the calculation of one ACR. The remaining two ACRs were
fulfilled by the default value of 18. The acute and chronic tests were conducted in different
laboratories using water of different physical characteristics; therefore, OPP's approach was used
to calculate the ACR. OPP's approach involves the use of the NOAEC in the calculations. The
calculated SCV for pyridaben is 0.004 |ig/L.

Detailed calculations for the SCV are shown below:

SACR = Geometric Mean of the ACRs

210


-------
SACR = V12.05# 18* 18 =15.74

SCV =

SACR

0.066

5CK = l574 = 0-°04W7/L

Table 5. Summary and comparison of chronic values for pyridaben.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

Pesticide

OPP Invertebrate

ALB
(NOAEC) (Year
published, species)

OW Tier II

value
(#of ACRs
filled, magnitude
relative to ALB)

OW Invertebrate-
only ALC (FCV)
(# of ACRs filled,

magnitude
relative to ALB)

Notes

Pyridaben

0.044 (ig/L

(2023, Daphnia
magna)

0.004 (ig/L
(GLI Tier II; 1
ACR, 11X)

NA

Two default ACRs of 18
used to derive GLI Tier
II value.

1.3.8.3 Pyridaben References

MRID 42680109. Willis, C.; Wilson, I. (1987) The Acute Toxicity of NC-129 to Rainbow Trout:
Final Report: Lab Project Number: AFT/86/022B: 88/0596. Unpublished study prepared by
Aquatox, Ltd. 40 p.

MRID 42680110. Willis, C. 1988. The Acute Toxicity of NC-129 toBluegill Sunfish: Final
Report: Lab Project Number: LSR/87/NAS021/600: 87/NAS021/600: 88/0595. Unpublished
study prepared by Life Science Research, Ltd. 51 p.

MRID 42680111. Willis, C.; Wilson, I. 1987. The Acute Toxicity of NC-129 to Daphnia Magna:
Final Report: Lab Project Number: AFT/86/024: 88/0594. Unpublished study prepared by
Aquatox, Ltd. 35 p.

MRID 43680401. Ward, G. 1994. Pyridaben Technical: Acute Toxicity to Bluegill, Lepomis
macrochirus, Under Flow- Through Conditions: Lab Project Number: 94/5002: 93062: ER93046.
Unpublished study prepared by Toxikon Environmental Sciences. 33 p.

MRID 43680402. Ward, G. 1994. Pyridaben Technical: Acute Toxicity to Rainbow Trout,
Oncorhynchus mykiss, Under Flow- Through Conditions: Lab Project Number: 94/5001: 93142:
ER93047. Unpublished study prepared by Toxikon Environmental Sciences. 33 p.

MRID 43680403. Bootman, J.; Jenkins, W.; O'Connor, J. (1989) NC-129: 21-Day Rainbow
Trout Toxicity Study Under Flow-Through Conditions: Lab Project Number: 89/0258:
88/NAS041/0824: 88/0824. Unpublished study prepared by Life Sciences Research Ltd. 41 p.

MRID 43680404. Graves, W.; Swigert, J. (1993) Pyridaben Technical A.I.: A 48-Hour Flow-
Through Acute Toxicity Test with the Cladoceran (Daphnia magna): Lab Project Number:
93/5169: ER 93057: 92076. Unpublished study prepared by Wildlife International Ltd. 45 p.

211


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MRID 43680408. Drottar, K.; Swigert, J. 1994. (Carbon 14)-Pyridaben: A Flow-Through Life
Cycle Toxicity Test with the Cladoceran, Daphnia magna: Lab Project Number: 94/5074: 93063:
ER 94001. Unpublished study prepared by Wildlife International Ltd. 61 p. U.S. EPA. 2015. Tier
II aquatic life community benchmarks for pyridaben. Office of Water and Office of Pesticide
Programs. Washington, D.C. March 2015.

MRID 43792106. Rhodes, J.; Leak, T.; Holmes, C. 1995. Full Life-Cycle Toxicity of BAS 300 I
(Pyridaben) to the Fathead Minnow (Pimephales promelas) Under Flow-Through Conditions:
Lab Project Number: 40571: 92160: ER94070. Unpublished study prepared by ABC Labs, Inc.
and BASF Corp. 1310 p.

U.S. EPA. 1985. Guidelines for derving numerical national water critera for the protection of
aquatic organisms and their uses. United States Environmental Protection Agency. Stephan,
C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and W.A. Brungs. PB85-227049.
National Technical Information Service, Springfield, VA. U.S.

U.S. EPA. 2010. Registration review: Preliminary problem formulation for environmental fate,
ecological risk, endangered species, and drinking water exposure assessments for pyridaben.
Office of Pesticide Programs. Washington, D.C. August 26, 2010.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

212


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2 Herbicides

2.1 Data-Rich Herbicides

2.1.1 Comparison of Aquatic Life Toxicity Values for Atrazine: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
(CWA) (U.S. EPA 2024) were obtained from the Office of Pesticide Programs (OPP) registration
review document for atrazine (U.S. EPA 2016) and an EPA ECOTOX Knowledgebase search
conducted in 2021. No chronic comparative analysis was conducted for atrazine.

2.1.1.1 Atrazine Acute Toxicity Data

Acute data for atrazine are shown in Table 1. Ranked invertebrate GMAVs from all data sources
are listed in Table 2.

Table 1. Acute toxicity data of atrazine to freshwater aquatic organisms.

ATDR specifics OW minimum data icc|Liiicnienls under Ihc Guidelines )

OW
MI)R'

Species

I X 50

S\1 AY

(IMAY

Source

M KID/
ECOTOX
r i: i

F

Acroneuria sp.

6700

6700

6700

ECOTOX

17138

B

Ameiurus melas

35000

35000

35000

ECOTOX

7199

Plant

Anabaena cylindrica

3600
1200

2078

585.0

ECOTOX

11659

ECOTOX

11659

Plant

Anabaena flos-aquae

230

230

OPP/
ECOTOX

41065203a/
344/ 103781

Plant

Anabaena inaequalis

100

30

54.77

ECOTOX

11659

ECOTOX

11659

Plant

Anabaena variabilis

4000
5000

4472

ECOTOX

11659

ECOTOX

11659

Plant

Ankistrodesmus braunii

60

60

60

ECOTOX

11424

H

Arrenurus sp.

<20

<20

<20

ECOTOX

153867

Plant

Azolla caroliniana

>100000

>100000

>100000

ECOTOX

176903

C

Bufo americanus

>48,000

>48000

>48000

ECOTOX

19124

B

Carassius auratus

60000
56000

58181

>58181

OPP/
ECOTOX

230303/
80976

ECOTOX

80976

B

Carassius carassius

58615
>100000

>100000

ECOTOX

80976

ECOTOX

7199

Plant

Ceratophyllum sp.





22

ECOTOX

152770

Plant

Ceratophyllum demersum

22

22

ECOTOX

19461

ECOTOX

112909

D

Ceriodaphnia dubia

>30000

>30000

>30000

ECOTOX

3590

F

Chironomus tentans

720

>4900

>25

OPP

24377

213


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()\\
MI)R'











M KID/

Species

LC 50

SM AN

(;ma\

Source

IX ()T()\
r i: i





>28000





ECOTOX

156062

F

Chironomus tepperi

25

25



ECOTOX

153818

Plant

Chlorella pyrenoidosa

300

547.7

547.7

ECOTOX

11659





1000





ECOTOX

11659

B

Coregonus fera

11200

17163

17163

ECOTOX

7792





26300





ECOTOX

7792

B

Cyprinus carpio

2142

6346

6346

ECOTOX

170959





18800





ECOTOX

6681

B

Danio rerio

6090

22048

22048

ECOTOX

174503





15630





ECOTOX

174503





34190





ECOTOX

174503





29060





ECOTOX

170833





39510





ECOTOX

170833





30740





ECOTOX

170833

D

Daphnia carinata

22400

28367

25262

ECOTOX

74233





23100





ECOTOX

74233





24600





ECOTOX

74233





25300





ECOTOX

74233





26700





ECOTOX

74233





60600





ECOTOX

160885

D

Daphnia magna

9400

22497



ECOTOX

50679





72000





ECOTOX

89626





16823





ECOTOX

170827

E

Diporeia sp.

>3000

>3000

>3000

ECOTOX

118745

E

Echinogammarus tibaldii

3300

3300

3300

ECOTOX

18621

Plant

Elodea canadensis

4.6

75.88

75.88

OPP

McGregor et
al 2008





79





ECOTOX

160884





116





ECOTOX

160884





305





ECOTOX

160884





80





ECOTOX

9159





75





ECOTOX

4634





187.8





ECOTOX

154073

G

Elliptic) complanata

>30000

>30000

>30000

ECOTOX

100597

E

Gammarus italicus

10100

10100

14168

ECOTOX

18621

E

Gammarus kischineffensis

18900

18900



ECOTOX

183521

E

Gammarus pulex

14900

14900



ECOTOX

5023

E

Hyalella azteca

1500

6594

6594

ECOTOX

118745





13000





ECOTOX

89626





14700





ECOTOX

17138

B

Ictalurus punctatus

220

220

220

ECOTOX

19124

214


-------
()\\
MI)R'

Species

LC 50

SM AN

(;ma\

Source

M KID/
IX ()T()\
r i: i

G

Lampsilis fasciola

>30000
>30000

>30000

>30000

ECOTOX

100597

ECOTOX

100597

G

Lampsilis siliquoidea

>30000
>30000
>30000
>30000

>30000



ECOTOX

99469

ECOTOX

99469

ECOTOX

100597

ECOTOX

100597

Plant

Lemna gibba

43
57

49.51

74.63

OPP

43074803

OPP

46150901

Plant

Lemna minor

5270
60
149.8
188.8
93.2
114

112.5

ECOTOX

176903

ECOTOX

13695

ECOTOX

174524

ECOTOX

160947

ECOTOX

174501

ECOTOX

170972

B

Lepomis macrochirus

24000
54510

36170

36170

OPP/
ECOTOX

24717/
80976

ECOTOX

344

C

Lithobates boylii

5517

5517

5517

ECOTOX

118706

C

Lithobates catesbeiana

410
>16000

>2561

ECOTOX

19124

ECOTOX

89626

G

Lumbriculus variegatus

>37100

>37100

>37100

ECOTOX

17138

D

Mesocyclops longisetus

1085
1503

1277

1277

ECOTOX

164050

ECOTOX

164050

Plant

Myriophyllum aquaticum

142.2
154.5
458.8
93.5
294

194.3

768.9

ECOTOX

164771

ECOTOX

164771

ECOTOX

164771

ECOTOX

160947

ECOTOX

170972

Plant

Myriophyllum sibiricum

2119

2119

ECOTOX

74985

Plant

Myriophyllum spicatum

1104

1104

ECOTOX

9159

Plant

Najas sp.

24

24

24

ECOTOX

19461

Plant

Navicula pelliculosa

60

60

60

OPP/
ECOTOX

41065203b/
344/ 103781

A

Oncorhynchus mykiss

5300

4500
870
13000
6031
5350
17000

5478

10769

OPP/
ECOTOX

24716/344

OPP/
ECOTOX

24716 pr 23-
3-3 / 80976

ECOTOX

19124

ECOTOX

89626

ECOTOX

80976

ECOTOX

80976

ECOTOX

7199

215


-------
()\\
MI)R'











M KID/

Species

LC 50

SM AN

(;ma\

Source

IX ()T()\
r i: i

A

Oncorhynchus kisutch

12000

12000



ECOTOX

89626

A

Oncorhynchus tshawytscha

19000

19000



ECOTOX

89626

Plant

Oscillatoria lutea

<1

< 1

< i

OPP

23544

E

Pacifastacus leniusculus

77900

77900

77900

ECOTOX

167249

B

Perca sp.

50000

50000

50000

ECOTOX

7199

G

Physella virgata

>34100

>34100

>34100

ECOTOX

17138

C

Physalaemus cuvieri

19690

19690

19690

ECOTOX

179653











OPP/

42547103 /

B

Pimephales promelas

20000

20000

20000

ECOTOX

78794

Plant

Potamogeton perfoliatus

53

53

53

ECOTOX

4634

Plant

Pseudanabaena galeata

14

14

14

ECOTOX

6712

C

Pseudacris regilla

1686

1686

1686

ECOTOX

118706

D

Pseudosida ramosa

13500

17565

17565

ECOTOX

153837





16900





ECOTOX

153837





17400





ECOTOX

153837





16400





ECOTOX

153837





16900





ECOTOX

153837





20900





ECOTOX

153837





16400





ECOTOX

153837





16400





ECOTOX

153837





21600





ECOTOX

153837





26000





ECOTOX

153837





19900





ECOTOX

153837





18700





ECOTOX

153837





13400





ECOTOX

153837





12300





ECOTOX

153837





15200





ECOTOX

153837





23500





ECOTOX

153837





16900





ECOTOX

153837





19700





ECOTOX

153837

Plant

Raphidocelis subcapitata

49

126.3

126.3

OPP

43074802





120





ECOTOX

344





53





ECOTOX

344





58.7





ECOTOX

11780





410





ECOTOX

11780





200





ECOTOX

16010





50





ECOTOX

17639





235





ECOTOX

18093





128.2





ECOTOX

18933





159





ECOTOX

19285





300





ECOTOX

19285

216


-------
OW
MDR-'

Species

LC 50

SM AN

(;ma\

Source

MRU)/
IX ()T()\
r i: i





110





ECOTOX

56747





118





ECOTOX

62246





220





ECOTOX

69584





200





ECOTOX

69584





200





ECOTOX

69584





55





ECOTOX

69630





115





ECOTOX

72626





76.4





ECOTOX

82748





89.9





ECOTOX

82748





86.1





ECOTOX

82748





63.4





ECOTOX

82748





94.9





ECOTOX

82748





81.4





ECOTOX

102060





1,600





ECOTOX

118745





277





ECOTOX

152770





138





ECOTOX

152770





103





ECOTOX

152770





107





ECOTOX

152770





65





ECOTOX

152770





126





ECOTOX

152770





196





ECOTOX

165277





87.6





ECOTOX

174384





130





ECOTOX

69631

B

Rhamdia quelen

10200

10200

10200

ECOTOX

111938

C

Rhinella arenarum

27160

27160

27160

ECOTOX

112588

B

Rutilus kutum

24950

26880

26880

ECOTOX

171062





28960





ECOTOX

171062

Plant

Scenedesmus abundans

110

110

210.3

ECOTOX

11677

Plant

Scenedesmus acutus var.
acutus

597.5

597.5



ECOTOX

164777

Plant

Scenedesmus quadricauda

100

141.4



ECOTOX

11659





200





ECOTOX

11659

Plant

Vallisneria americana

163

163.0

163

ECOTOX

4634

G

Villosa constricta

>30000

>30000

>30000

ECOTOX

100597

G

Villosa delumbis

>30000

30000



ECOTOX

100597

C

Xenopus tropicalis

9620

9620

9620

ECOTOX

178499

a OW MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important

warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

217


-------
E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Acute Benchmark Values

The OPP non-vascular plant benchmark value for atrazine is <1 |ig/L, which is the LC50 for 0.
lutea. The OPP vascular plant benchmark is 4.6 |ig/L, which is the LC50 for E. canadensis.

The OPP invertebrate acute benchmark value for atrazine is 360 |ig/L, which is V2 the LC50 for C.
tentans.

The OPP fish acute benchmark value is 2,650 |ig/L, which is V2 the LC50 for 0. mykiss.
OW Acute Criterion

There is no acute criterion, criterion maximum concentration (CMC), for atrazine. An illustrative
example was developed for this analysis, using all available data (Table 2). The FAV calculated
following the U.S. EPA (1985) methodology for the 51 genera in the atrazine dataset was 11.47
|ig/L (Table 3).

Table 2. Atrazine SMAVs and GMAVs (^ig/L).

(ionus

Species

S\1 AY

(IMAY

Riink

Percentile

()\Y
MIJR
C ¦ roup

Azolla*

caroliniana

>100,000

100,000

51

0.981

Plant

Pacifastacus

leniusculus

77,900

77,900

50

0.962

E

Carassius*

auratus

58,181

76,277

49

0.942

B

Perca

sp.

50,000

50,000

48

0.923

B

Bufo*

americanus

>48,000

48,000

47

0.904

C

Lumbriculus*

variegatus

>37,100

37,100

46

0.885

G

Lepomis

macrochirus

36,170

36,170

45

0.865

B

Ameiurus

melas

35,000

35,000

44

0.846

B

Physella*

virgata

>34,100

34,100

43

0.827

G

Elliptio*

complanata

>30,000

30,000

42

0.808

G

Lampsilis*

fasciola

>30,000

30,000

41

0.788

G

Villosa*

constricta

>30,000

30,000

40

0.769

G

Ceriodaphnia *

dubia

>30,000

30,000

39

0.750

D

Rhinella

arenarum

27,160

27,160

38

0.731

C

Rutilus

kutum

26,880

26,880

37

0.712

B

Daphnia

carinata

28,367

25,262

36

0.692

D

Danio

rerio

22,048

22,048

35

0.673

B

Pimephales

promelas

20,000

20,000

34

0.654

B

Physalaemus

cuvieri

19,690

19,690

33

0.635

C

218


-------
(ionus

Species

SM AN

(IMAV

kiink

Percentile

OW
MIJR

(J roup

Pscudosida

ramosa

l~,5o5

r.xo

32

O.ol5

D

Coregonus

fera

17,163

17,163

31

0.596

B

Gammarus

italicus

10,100

14,168

30

0.577

E

Oncorhynchus

kisutch

12,000

10,769

29

0.558

A

Rhamdia

quelen

10,200

10,200

28

0.538

B

Xenopus

tropicalis

9,620

9,620

27

0.519

C

Acroneuria

sp.

6,700

6,700

26

0.500

F

Hyalella

azteca

6,594

6,594

25

0.481

E

Cyprinus

carpio

6,346

6,346

24

0.462

B

Lithobates*

boylii

5,517

3,759

23

0.442

C

Echinogammarus

tibaldii

3,300

3,300

22

0.423

E

Diporeia*

sp.

>3,000

3,000

21

0.404

E

Pseudacris

regilla

1,686

1,686

20

0.385

C

Mesocyclops

longisetus

1,277

1,277

19

0.365

D

Myriophyllum

aquaticum

194.3

768.9

18

0.346

Plant

Anabaena

cylindrica

2,078

585.0

17

0.327

Plant

Chlorella

pyrenoidosa

547.7

547.7

16

0.308

Plant

Chironomus*

tentans

>4,490

335

15

0.288

F

Ictalurus

punctatus

220

220

14

0.269

B

Scenedesmus

abundans

110

210.3

13

0.250

Plant

Vallisneria

americana

163.0

163.0

12

0.231

Plant

Raphidocelis

subcapitata

126.3

126.3

11

0.212

Plant

Elodea

canadensis

75.88

75.88

10

0.192

Plant

Lemna

gibba

49.51

74.63

9

0.173

Plant

Navicula

pelliculosa

60

60

8

0.154

Plant

Ankistrodesmus

braunii

60

60

7

0.135

Plant

Potamogeton

perfoliatus

53

53

6

0.115

Plant

Najas

sp.

24

24

5

0.096

Plant

Ceratophyllum

demersum

22

22

4

0.077

Plant

Arrenurus*

sp.

<20

20

3

0.058

H

Pseudanabaena

galeata

14

14

2

0.038

Plant

Oscillatoria *

lutea

<1

1

1

0.019

Plant

* (non-definitive value, less than value)
a OW MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important
warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

219


-------
F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

Table 3. Genus-level acute HCos for atrazine calculated following the U.S. EPA (1985)
methodology.

.V

Kiink

(;m.w

InKiMAY)

Iikc;mw i:

l*=K/( N+l)

mii-iiP)

51

4

22

3.091

9.55

0.0769

0.2774



3

20

2.996

8.97

0.0577

0.2402



2

14

2.639

6.96

0.0385

0.1961



1

1

0.000

0.00

0.0192

0.1387



Sum:



8.73

25.5

0.192

0.852







S2 =

604.19

L =

-3.056

A =

2.440

FAV =

11.47

CMC =

5.7

220


-------
Table 4. Summary and comparison of acute values for atrazine.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

Pesticide

Most Sensitive OPP ALB
(Year published, species)

OW Illustrative ALC example
(# of MDRs filled, magnitude
relative to ALB)

OW Modified HCos
(# of MDRs filled,
# of genera available,
magnitude relative to ALB)

Atrazine1

< 1 ^g/L

(2016; Oscillatoria lute a;
nonvascular plant)

5.7 (ig/L

(illustrative ALC example
calculated for this analysis; 8
MDRs filled, 0.18X)

NA

'No 304(a) ALC recommendation available but has sufficient data to develop an illustrative ALC example for the purposes of
these analyses only.

Figure 1 shows a genus-level sensitivity distribution for the atrazine dataset. Major taxonomic
groups are delineated by different symbols, and invertebrate genera are identified by name. Lines
denoting the OPP acute benchmark values and the illustrative OW ALC example.

221


-------
1007000

10,000

1,000

UO

3 100


-------
2.1.1.2 Atrazine References

MRID 23544. Ramirea Torrest, A.M, and L.M. O'Flaherty. 1976. Influence of pesticides on
Chlorella, Chlorococcum, Stigeoclonium (Chlorophyceae), Tribonema, Vaucheria
(Xanthophyceae) and Oscillatoria (Cyanophyceae). Phycoleia 15(1): 376-387.

MRID 24377. U.S. Environmental Protection Agency. 1976. Chronic toxicity of atrazine to
selected aquatic invertebrates and fishes. Environmental Research Laboratory, Office of
Research and Development, USEPA, Duluth, MN. EPA -600/3-76-047

MRID 24716. Atrazine Acute toxicity in Rainbow Trout —SR. 00625-023-1; 230303-0-P.

MRID 41065203. Hughes, J. S. 1986. The toxicity of atrazine, Lot No. FL-850612 to four
species of aquatic plants. Unpublished study conducted by Malcolm Pirnie, Inc, White Plains,
NY. Laboratory Study No. 267-28-1100. Sponsored by Agricultural Division Ciba-Geigy,
Greensboro, NC. Study completed March 17, 1986.

MRID 42547103. Dionne, E. 1992. Chronic Toxicity to the Fathead Minnow (Pimephales
promelas) during a full life-cycle exposure. Unpublished study conducted by Springborn
Laboratories, Inc., Wareham, MA. Laboratory report No. 92-7-4324. Sponsored by Agricultural
Division, Ciba-Geigy Corporation, Greensbore, NC.

MRID 43074802. Hobert, J.R. 1993. Toxicity to the Freshwater Green Alga, Selenastrum
carpricornutum. Unpublished study conducted by Springborn Laboratories, Inc., Wareham, MA.
Study No. 93-4-4751. Sponsored by Ciba Plant Protection, Ciba-Geigy Corporation,
Greensboro, NC. Study completed November 15, 1993.

MRID 43074803. Hoberg, J.R. 1983. Atrazine Technical - Toxicity to Duckweed (Lemna
gibba). Unpublished study conducted by Springborn Laboratories, Inc, Wareham, MA. Study
No. 93-11-5053. Sponsored by Ciba Plant Protection, Ciba-Geigy Corp, Greensboro, NC. Study
completed December 21, 1983.

MRID 80976 associated with MRID 230303. Beliles, R.P., and W.J., Jr. Scott. 1965. Atrazine
Safety Evaluations on Fish and Wildlife (Bobwhite Quail, Mallard Ducks, Rainbow Trout,
Sunfish, and Goldfish). Prepared by Woodard Res. Corp., Submitted by Geigy Chem. Co.,
Ardsley, NY (MRID No.00059214), 9 p. ECOREF #80976

Abdel-Hamid, M.I.. 1996. Development and Application of a Simple Procedure for Toxicity
Testing Using Immobilized Algae. Water Sci. Technol. 33(6): 129-138. ECOREF #69584

Bathe, R., K. Sachsse, L. Ullmann, W.D. Hormann, F. Zak, and R. Hess. 1975. The Evaluation
of Fish Toxicity in the Laboratory. Proc. Eur. Soc. Toxicol. 16:113-124. ECOREF #7199

Baxter, L., R.A. Brain, L. Lissemore, K.R. Solomon, M.L. Hanson, and R.S. Prosser. 2016.
Influence of Light, Nutrients, and Temperature on the Toxicity of Atrazine to the Algal Species
Raphidocelis subcapitata: Implications for the Risk Assessment of Herbicides. Ecotoxicol.
Environ. Saf. 132:250-259. ECOREF #174384

Beliles, R.P., and W.J.,Jr. Scott. 1965. Atrazine Safety Evaluations on Fish and Wildlife
(Bobwhite Quail, Mallard Ducks, Rainbow Trout, Sunfish, and Goldfish). Prepared by Woodard
Res. Corp., Submitted by Geigy Chem. Co., Ardsley, NY (MRID No.00059214): 9 p. ECOREF
#80976.

223


-------
Berard, A., U. Dorigo, I. Mercier, K. Becker-Van Slooten, D. Grandjean, and C. Leboulanger.
2003. Comparison of the Ecotoxicological Impact of the Triazines Irgarol 1051 and Atrazine on
Microalgal Cultures and Natural Microalgal Communities in Lake Geneva. Chemosphere 53(8):
935-944. ECOREF #72626.

Birge, W.J., J.A. Black, A.G. Westerman, and B.A. Ramey. 1983. Fish and Amphibian Embryos
- a Model System for Evaluating Teratogenicity. Fundam. Appl. Toxicol. 3:237-242. ECOREF
#19124.

Brain, R.A., J. Hoberg, A.J. Hosmer, and S.B. Wall. 2012. Influence of Light Intensity on the
Toxicity of Atrazine to the Submerged Freshwater Aquatic Macrophyte Elodea canadensis.
Ecotoxicol. Environ. Saf. 79:55-61. ECOREF #160884.

Bringolf, R.B., W.G. Cope, C.B. Eads, P.R. Lazaro, M.C. Barnhart, and D. Shea. 2007. Acute
and Chronic Toxicity of Technical-Grade Pesticides to Glochidia and Juveniles of Freshwater
Mussels (Unionidae). Environ. Toxicol. Chem. 26(10): 2086-2093. ECOREF #100597.

Bringolf, R.B., W.G. Cope, M.C. Barnhart, S. Mosher, P.R. Lazaro, and D. Shea. 2007. Acute
and Chronic Toxicity of Pesticide Formulations (Atrazine, Chlorpyrifos, and Permethrin) to
Glochidia and Juveniles of Lampsilis siliquoidea. Environ. Toxicol. Chem. 26(10): 2101-2107.
ECOREF #99469.

Brodeur, J.C., G. Svartz, C.S. Perez-Coll, D.J.G. Marino, and J. Herkovits. 2009. Comparative
Susceptibility to Atrazine of Three Developmental Stages of Rhinella arenarum and Influence on
Metamorphosis: Non-Monotonous Acceleration of the Time to Climax and Delayed Tail
Resorption. Aquat. Toxicol. 91(2): 161-170. ECOREF #112588.

Brooke, L.T. 1991. Results of Freshwater Exposures with the Chemicals Atrazine, Biphenyl,
Butachlor, Carbaryl, Carbazole, Dibenzofuran, 3,3'-Dichlorobenzidine, Dichlorvos, 1,2-
Epoxyethylbenzene (Styrene Oxide), Isophorone, Isopropalin, Ox. Center for Lake Superior
Environmental Studies, University of Wisconsin, Superior, WI:110. ECOREF #17138.

Burrell, R.E., W.E. Inniss, and C.I. Mayfield. 1985. Detection and Analysis of Interactions
Between Atrazine and Sodium Pentachlorophenate with Single and Multiple Algal-Bacterial
Populations. Arch. Environ. Contam. Toxicol. 14:167-177. ECOREF #11424.

Choung, C.B., R.V. Hyne, M.M. Stevens, and G.C. Hose. 2010. A Low Concentration of
Atrazine does not Influence the Acute Toxicity of the Insecticide Terbufos or Its Breakdown
Products to Chironomus tepperi. Ecotoxicology 19(8): 1536-1544. ECOREF #153818.

Davis, D.E. 1980. Effects of Herbicides on Submerged Seed Plants. Completion Rep.Project A-
067-ALA, Office of Water Res.and Technol., Washington, DC: 19 p. ECOREF #9159.

Delia Vechia, J.F., C. Cruz, A.F. Silva, W.R., Jr. Cerveira, and N. Garlich. 2016. Macrophyte
Bioassay Applications for Monitoring Pesticides in the Aquatic Environment. Planta Daninha
34(3): 597-603. ECOREF #176903.

Demirci, K. Guven, D. Asma, S. Oqut, and P. Ugurlu. 2018. Effects of Endosulfan,
Thiamethoxam, and Indoxacarb in Combination with Atrazine on Multi-Biomarkers in
Gammarus kischineffensis. Ecotoxicol. Environ. Saf. 147:749-758. ECOREF #183521.

224


-------
Dionne, E. 1992. Chronic Toxicity to the Fathead Minnow (Pimephales promelas) During a Full
Life-Cycle Exposure. Lab. Study #92-7-4324, CIBA-GEIGY Corp., Greensboro, NC:439 p.
ECOREF #78794.

Ebke, K.P., C. Felten, and L. Doren. 2013. Impact of Heterophylly on the Sensitivity of
Myriophyllum aquaticum Biotests. Environ. Sci. Eur. 25(6): 9 p. ECOREF #164771.

Fai, P.B., A. Grant, and B. Reid. 2007. Chlorophyll a Fluorescence as a Biomarker for Rapid
Toxicity Assessment. Environ. Toxicol. Chem. 26(7): 1520-1531. ECOREF #102060.

Fairchild, J., S. Ruessler, M. Nelson, and P. Haverland. 1994. Bioavailability and Toxicity of
Agricultural Chemicals in Runoff from MSEA Sites: Potential Impacts on Non-Target Aquatic
Organisms: An Aquatic Hazard Assessment of Four Herbicides Using Six Species of Algae and
Five S. Final report for IAG DW14935600-01-2. Environmental Research Laboratory, U.S.
Environmental Protection Agency, Duluth, MN:123 p. ECOREF #152770.

Fairchild, J.F., D.S. Ruessler, and A.R. Carlson. 1998. Comparative Sensitivity of Five Species
of Macrophytes and Six Species of Algae to Atrazine, Metribuzin, Alachlor, and Metolachlor.
Environ. Toxicol. Chem. 17(9): 1830-1834. ECOREF #19461.

Fairchild, J.F., D.S. Ruessler, P.S. Haverland, and A.R. Carlson. 1997. Comparative Sensitivity
of Selenastrum capricornutum and Lemna minor to Sixteen Herbicides. Arch. Environ. Contam.
Toxicol. 32(4): 353-357. ECOREF #18093.

Forney, D.R., and D.E. Davis. 1981. Effects of Low Concentrations of Herbicides on Submersed
Aquatic Plants. Weed Sci. 29:677-685. ECOREF #4634.

Freitas, E.C., and O. Rocha. 2011. Acute Toxicity Tests with the Tropical Cladoceran
Pseudosida ramosa: The Importance of Using Native Species as Test Organisms. Arch. Environ.
Contam. Toxicol. 60(2): 241-249. ECOREF #153837.

Gala, W.R., and J.P. Giesy. 1990. Flow Cytometric Techniques to Assess Toxicity to Algae.
ASTM Spec. Tech. Publ. 13:237-246. ECOREF #18933.

Garrett, D.C. 2004. Effects of Methanol, Atrazine, and Copper on the Ultrastructure of
Pseudokirchneriella subcapitata (Selenastrum capricornutum). Ph.D. Thesis, University of North
Texas, Denton, TX:192 p. ECOREF #82748.

Geyer, H., I. Scheunert, and F. Korte. 1985. The Effects of Organic Environmental Chemicals on
the Growth of the Alga Scenedesmus subspicatus: A Contribution to Environmental Biology.
Chemosphere 14(9): 1355-1369. ECOREF #11677.

Gunkel, G., and H. Kausch.1976. Acute Toxicity of Atrazine (S-Triazine) on Coregonus fera
Under Starvation Conditions. Arch. Hydrobiol. Suppl. 48(2): 207-234. ECOREF #7792.

Gutierrez, M.F., A.M. Gagneten, and J.C. Paggi. 2013. Acute and Behavioral Sensitivity of
Mesocyclops longisetus to Atrazine and Endosulfan Formulations Under Predation Pressure.
Water Air Soil Pollut. 224(1): 9 p. ECOREF #164050.

He, H., J. Yu, G. Chen, W. Li, J. He, and H. Li. 2012. Acute Toxicity of Butachlor and Atrazine
to Freshwater Green Alga Scenedesmus obliquus and Cladoceran Daphnia carinata. Ecotoxicol.
Environ. Saf. 80:91-96. ECOREF #160885.

225


-------
Hoberg, J.R. 1991. Atrazine Technical - Toxicity to the Freshwater Green Alga Selenastrum
capricornutum. Final SLI Rep.No.91-1-3600, Springborn Lab. Inc., Environ. Sci. Div.,

Wareham, MA: 50 p. ECOREF #69631.

Hoberg, J.R. 1993. Atrazine Technical - Toxicity to the Freshwater Green Alga, (Selenastrum
capri cornutum). Final SLI Rep.No.93-4-4751, Springborn Lab. Inc., Environ. Sci. Div.,
Wareham, MA: 63 p. ECOREF #69630.

Hughes, J.S., J.S. Reed, and S.K. Krishnaswami. 1986. The Toxicity of Atrazine, Lot No. FL-
850612, to Four Species of Aquatic Plants. Final Rep. from Malcom Pirnie, Inc.to Giba-Geigy
Corp., Greensboro, NC: MRID No.410652-03, U.S.EPA, Duluth, MN, 71 p. ECOREF# 103781.

James-Yi, S.A. 2008. Systematics, Ecology, and Distribution of Water Mites (Acari:
Parasitengonina). Ph.D. Thesis, University of Illinois at Urbana-Champaign, Champaign, IL:181
p. ECOREF #153867.

Johnson, I.C., A.E. Keller, and S.G. Zam. 1993. A Method for Conducting Acute Toxicity Tests
with the Early Life Stages of Freshwater Mussels. ASTM Spec. Tech. Publ.: 381-396 ECOREF
#50679.

Kallqvist, T., and R. Romstad. 1994. Effects of Agricultural Pesticides on Planktonic Algae and
Cyanobacteria — Examples of Interspecies Sensitivity Variations. Norw. J. Agric. Sci. Suppl.
13:117-131. ECOREF #16010.

Kerby, J.L. 2006. Pesticide Effects on Amphibians: A Community Ecology Perspective. Ph.D.
Thesis, University of California, Davis: 146 p. ECOREF #118706.

Khoshnood, Z., S. Jamili, S. Khodabandeh, A. Mashinchian Moradi, and A.A. Motallebi
Moghanjoghi. 2014. Histopathological Effects and Toxicity of Atrazine Herbicide in Caspian
Kutum, Rutilus frisii kutum, Fry. Iran. J. Fish. Sci. 13(3): 702-718. ECOREF #171062.

Kirby, M.F., and D.A. Sheahan. 1994. Effects of Atrazine, Isoproturon, and Mecoprop on the
Macrophyte Lemna minor and the Alga Scenedesmus subspicatus. Bull. Environ. Contam.
Toxicol. 53(1): 120-126. ECOREF #13695.

Knezevic, V., T. Tunic, P. Gajic, P. Marjan, D. Savic, D. Tenji, and I. Teodorovic. 2016. Getting
More Ecologically Relevant Information from Laboratory Tests: Recovery of Lemna minor
After Exposure to Herbicides and Their Mixtures. Arch. Environ. Contam. Toxicol. 71(4): 572-
588. ECOREF #174524.

Kreutz, L.C., L.J.G. Barcellos, T.O. Silva, D. Anziliero, D. Martins, M. Lorenson, A.
Marteninghe, and L.B. Da Silva. 2008. Acute Toxicity Test of Agricultural Pesticides on Silver
Catfish (Rhamdia quelen) Fingerlings. Ciencia Rural 38(4): 1050-1055. ECOREF #111938.

Mayer, P., J. Frickmann, E.R. Christensen, andN. Nyholm. 1998. Influence of Growth
Conditions on the Results Obtained in Algal Toxicity Tests. Environ. Toxicol. Chem. 17(6):
1091-1098. ECOREF #19285.

McGregor, E.B., K.R. Solomon, and M.L Hanson. 2008. Effects of planting system design on the
toxicological sensitivity of Myriophyllum spicatum and Elodea canadensis to atrazine.
Chemosphere 73(3): 249-260. https://doi.Org/10.1016/j.chemosphere.2008.06.045.

226


-------
McNamara, P.C. 1991. Atrazine Technical - Acute Toxicity to Midge (Chironomus tentans)
Under Flow-Through Conditions. SLI Report No.91-2-3649, Springborn Laboratories Inc.,
Wareham, MA: 61 p. ECOREF #156062.

Mofeed, J., and Y.Y. Mosleh. 2013. Toxic Responses and Antioxidative Enzymes Activity of
Scenedesmus obliquus Exposed to Fenhexamid and Atrazine, Alone and in Mixture. Ecotoxicol.
Environ. Saf. 95: 234-240. ECOREF #164777.

Neskovic, N.K., I. Elezovic, V. Karan, V. Poleksic, and M. Budimir.1993. Acute and Subacute
Toxicity of Atrazine to Carp (Cyprinus carpio L.). Ecotoxicol. Environ. Saf. 25: 173-182.
ECOREF #6681.

Okamura, H., I. Aoyama, D. Liu, R.J. Maguire, G.J. Pacepavicius, and Y.L. Lau. 2000. Fate and
Ecotoxicity of the New Antifouling Compound Irgarol 1051 in the Aquatic Environment. Water
Res. 34(14): 3523-3530. ECOREF #56747.

Oris, J.T., R.W. Winner, and M.V. Moore. 1991. A Four-Day Survival and Reproduction
Toxicity Test for Ceriodaphnia dubia. Environ. Toxicol. Chem. 10(2): 217-224. ECOREF #3590.

Pan, H., X. Li, X. Xu, and S. Gao. 2009. Phytotoxicity of Four Herbicides on Ceratophyllum
demersum, Vallisneria natans and Elodea nuttallii. J. Environ. Sci. 21:307-312. ECOREF
#112909.

Pantani, C., G. Pannunzio, M. De Cristofaro, A.A. Novelli, and M. Salvatori. 1997. Comparative
Acute Toxicity of Some Pesticides, Metals, and Surfactants to Gammarus italicus Goedm. and
Echinogammarus tibaldii Pink, and Stock (Crustacea: Amphipoda). Bull. Environ. Contam.
Toxicol. 59(6): 963-967. ECOREF #18621.

Perez, J., I. Domingues, A.M.V.M. Soares, and S. Loureiro. 2011. Growth Rate of
Pseudokirchneriella subcapitata Exposed to Herbicides Found in Surface Waters in the Alqueva
Reservoir (Portugal): A Bottom-up Approach Using Binary Mixtures. Ecotoxicology 20(6):
1167-1175. ECOREF #165277.

Phyu, Y.L., M.St. J. Warne, and R.P. Lim. 2004. Toxicity of Atrazine and Molinate to the
Cladoceran Daphnia carinata and the Effect of River Water and Bottom Sediment on Their
Bioavailability. Arch. Environ. Contam. Toxicol. 46(3): 308-315. ECOREF #74233.

Ralston-Hooper, K., J. Hardy, L. Hahn, H. Ochoa-Acuna, L.S. Lee, R. Mollenhauer, and M.S.
Sepulveda. 2009. Acute and Chronic Toxicity of Atrazine and Its Metabolites Deethylatrazine
and Deisopropylatrazine on Aquatic Organisms. Ecotoxicology 18(7): 899-905. ECOREF
#118745.

Rentz, N.C. 2009. Evaluating the Field and Laboratory Efficacy of a Toxicity Test for the
Aquatic Macrophyte Elodea canadensis. M.S. Thesis, University of Manitoba, Canada: 219 p.,
ECOREF #154073.

Roshon, R.D. 1997. A Toxicity Test for the Effects of Chemicals on the Non-Target Submersed
Aquatic Macrophyte, Myriophyllum sibiricum Komarov. Ph.D. Thesis, University of Guelph,
Ontario, Canada:464 p. ECOREF #74985.

227


-------
Saka, M., N. Tada, and Y. Kamata. 2018. Chronic Toxicity of 1,3,5-Triazine Herbicides in the
Postembryonic Development of the Western Clawed Frog Silurana tropicalis. Ecotoxicol.
Environ. Saf. 147: 373-381. ECOREF #178499.

Seguin, F., C. Leboulanger, F. Rimet, J.C. Druart, and A. Berard. 2001. Effects of Atrazine and
Nicosulfuron on Phytoplankton in Systems of Increasing Complexity. Arch. Environ. Contam.
Toxicol. 40(2): 198-208. ECOREF #62246.

Sengupta, N., E.J. Litoff, and W.S. Baldwin. 2015. The HR96 Activator, Atrazine, Reduces
Sensitivity of D. magna to Triclosan and DHA. Chemosphere 128: 299-306. ECOREF #170827.

Stratton, G.W. 1984. Effects of the Herbicide Atrazine and Its Degradation Products, Alone and
in Combination, on Phototrophic Microorganisms. Arch. Environ. Contam. Toxicol. 13(1): 35-
42. ECOREF #11659.

Taylor, E.J., S.J. Maund, and D. Pascoe. 1991. Toxicity of Four Common Pollutants to the
Freshwater Macroinvertebrates Chironomus riparius Meigen (Insecta: Diptera) and Gammarus
pulex (L.). Arch. Environ. Contam. Toxicol. 21: 371-376. ECOREF #5023.

Teodorovic, I., V. Knezevic, T. Tunic, M. Cucak, J.N. Lecic, A. Leovac, and I.I. Tumbas. 2012.
Myriophyllum aquaticum Versus Lemna minor: Sensitivity and Recovery Potential After
Exposure to Atrazine. Environ. Toxicol. Chem. 31(2): 417-426. ECOREF #160947.

Tunic, T., V. Knezevic, U. Kerkez, A. Tubic, D. Sunjka, S. Lazic, D. Brkic, and I. Teodorovic.
2015. Some Arguments in Favor of a Myriophyllum aquaticum Growth Inhibition Test in a
Water-Sediment System as an Additional Test in Risk Assessment of Herbicides. Environ.
Toxicol. Chem. 34: 2104-2115. ECOREF #170972.

Turbak, S.C., S.B. Olson, and G.A. McFeters. 1986. Comparison of Algal Assay Systems for
Detecting Waterborne Herbicides and Metals. Water Res. 20(1): 91-96. ECOREF #11780.

U.S. Environmental Protection Agency. 1992. Pesticide Ecotoxicity Database (Formerly:
Environmental Effects Database (EEDB)). Environmental Fate and Effects Division, U.S.EPA,
Washington, D.C. ECOREF #344.

U.S. Environmental Protection Agency. 2024. Draft Comparison of Aquatic Life Protective
Values Developed for Pesticides under the Federal Insecticide, Fungicide, and Rodenticide Act
(FIFRA) and the Clean Water Act (CWA). EPA-820-D-24-002.

Velisek, J., A. Kouba, and A. Stara. 2013. Acute Toxicity of Triazine Pesticides to Juvenile
Signal Crayfish (Pacifastacus leniusculus). Neuroendocrinol. Lett. 34(2): 31-36. ECOREF
#167249.

Versteeg, D.J. 1990. Comparison of Short- and Long-Term Toxicity Test Results for the Green
Alga, Selenastrum capricornutum. ASTM Spec. Tech. Publ.: 40-48. ECOREF #17639.

Wan, M.T., C. Buday, G. Schroeder, J. Kuo, and J. Pasternak. 2006. Toxicity to Daphnia magna,
Hyalella azteca, Oncorhynchus kisutch, Oncorhynchus mykiss, Oncorhynchus tshawytscha, and
Rana catesbeiana of Atrazine, Metolachlor, Simazine, and Their Formulated Products. Bull.
Environ. Contam. Toxicol. 76(1): 52-58. ECOREF #89626.

228


-------
Wang, Y., L. Lv, Y. Yu, G. Yang, Z. Xu, Q. Wang, and L. Cai. 2017. Single and Joint Toxic
Effects of Five Selected Pesticides on the Early Life Stages of Zebrafish (Denio rerio).
Chemosphere 170: 61-67. ECOREF #174503.

Wrubleswski, J., F.W., Jr. Reichert, L. Galon, P.A. Hartmann, and M.T. Hartmann. 2018. Acute
and Chronic Toxicity of Pesticides on Tadpoles of Physalaemus cuvieri (Anura,

Leptodactylidae). Ecotoxicology 27(3): 360-368. ECOREF #179653.

Xing, H., T. Liu, Z. Zhang, X. Wang, and S. Xu. 2015. Acute and Subchronic Toxic Effects of
Atrazine and Chlorpyrifos on Common Carp (Cyprinus carpio L.): Immunotoxicity Assessments.
Fish Shellfish Immunol. 45: 327-333. ECOREF #170959.

Yan, H., S. Huang, and M. Scholz. 2015. Kinetic Processes of Acute Atrazine Toxicity to
Brachydanio rerio in the Presence and Absence of Suspended Sediments. Water Air Soil Pollut.
226(3): 13 p. ECOREF #170833.

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2.1.2 Comparison of Aquatic Life Toxicity Values for Propazine: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
('CWA) (U.S. EPA 2024) were obtained from the Office of Pesticide Programs (OPP) registration
review document for propazine (U.S. EPA 2016) and an EPA ECOTOX Knowledgebase search
conducted in 2021.

2.1.2.1 Propazine Acute Toxicity Data

Acute data for propazine are shown in Table 1. Ranked invertebrate GMAVs from all data
sources are listed in Table 2.

Table 1. Acute toxicity data of propazine to freshwater aquatic organisms.

MDR specifies OW minimum data requirements under the Guidelines.)	

OW
Ml)k'

Species

IX 50

S\1 AY

(;ma\

Source

MRID/IX OTO\

ri:i

Plant

Blue Green Algae (Anabaena
flos-aquae)

160

160

160

OPP/
ECOTOX

44287312/344

Plant

Duckweed (Lemna gibba)

100

100

100

OPP/ ECOTOX

44287309 / 344

B

Bluegill Sunfish

(Lepomis macrochirus)

>4380
>4500

>4440

>4440

OPP

48036203

OPP/
ECOTOX

178499

Plant

Freshwater Diatom (Navicula
pelliculosa)

24.8

24.8

24.8

OPP/ ECOTOX

44287310/344

A

Rainbow Trout (Oncorhynchus
mykiss)

5000
16500

9083

9083

OPP

47452301

OPP

34123

Plant

Green Algae

(Raphidocelis subcapitata)

29

29

29

OPP/
ECOTOX

44287308 / 344

C

Western Clawed Frog

(Xenopus tropicalis)

>5200

>5200

>5200

ECOTOX

178499

a OW MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important
warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Acute Benchmark Values

The OPP non-vascular plant benchmark value for propazine is 24.8 |ig/L, which is the LCso for
N. pelliculosa. The OPP vascular plant benchmark value is 100 |ig/L, which is the LCso for L.
gibba.

The OPP invertebrate acute benchmark value is >2,660 |ig/L, which is '/2 the LC50 for D. magna.

230


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The OPP fish acute benchmark value is >2,190 |ig/L, which is V2 the LC50 for L. macrochirus.
GLI Tier II Acute Value Calculation

The acceptable acute dataset for propazine fulfills three of the eight MDRs, corresponding to the
use of a Secondary Acute Factor (SAF) of 8. Applying the SAF to the lowest, most sensitive
GMAV regardless of taxa (i.e., 28.4 |ig/L for the freshwater diatom (Naviculapelliculosa)), the
calculated Secondary Acute Value (SAV) is 3.1 |ig/L. The Secondary Maximum Criterion
(SMC), which is calculated as half the SAV, is 1.55 |ig/L. Detailed calculations for the SMC are
shown below:

Lowest GMAV

28.4

SAV = — = 3.1 \ig/L
SAV

SMC= —

3.55

SMC = —= 1.55 |xg/L

Modified Acute HC05

The genus-level modified acute HC05 calculated following the U.S. EPA (1985) methodology for
the four most sensitive genera regardless of taxa (Table 2) in the propazine dataset was 8.468
|ig/L (Table 3).

Table 2. Propazine SMAVs and G

MAVs (pg/L).

(ioniis

Species

S\1 AY

(;ma\

(IMAY
kiink

MI)R

(iroup

Oncorhynchus

mykiss

9,083

9,083

3

A

Xenopus

tropicalis

>5,200

>5,200

2

C

Lepomis

macrochirus

>4,440

>4,440

1

B

Anabaena

flos-aquae

160

160

4

Plant

Lemna

gibba

100

100

3

Plant

Raphidocelis

subcapitata

29

29

2

Plant

Navicula

pelliculosa

24.8

24.8

1

Plant

231


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Table 3. Modified acute HCos for propazine calculated following the U.S. EPA (1985)

N

Rank

GMAV

ln(GMAV)

ln(GMAV)2

P=R/(N+1)

sqrt(P)

7

4

160

5.075

25.76

0.5000

0.7071



3

100

4.605

21.21

0.3750

0.6124



2

29

3.367

11.34

0.2500

0.5000



1

24.8

3.211

10.31

0.1250

0.3536



Sum:



16.26

68.6

1.250

2.173







S2 =

36.39

L =

0.787

A =

2.136

FAV =

8.468

CMC =

4.2

Table 4. Summary and comparison of acute values for propazine.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio >1 indicates the OPP value is higher than the OW value.	

Pesticide

Most Sensitive OPP ALB
(Year published, species)

OW GLI Tier II value
(# of MDRs filled, magnitude
relative to ALB)

OW Modified HCos
(# of MDRs filled,
# of genera available,
magnitude relative to ALB)

Propazine

24.8 ng/L

(2022; Naviculapelliculosa;
nonvascular plant)

1.55 ng/L

(GLI Tier II; 4 MDRs filled*, 16X)

4.2 (ig/L

(3 MDRs, 7 genera, 5.9X)

Figure 1 shows a genus-level sensitivity distribution for the propazine dataset. Major taxonomic
groups are delineated by different symbols. Lines denoting the OPP acute benchmark values,
GLI Tier II calculated acute value, and modified HCos value are included.

232


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10,000

1,000

&Q

3 100


-------
2.1.2.2 Propazine Chronic Toxicity Data
Data Sources and Considerations

Chronic toxicity data for propazine were consolidated by OW and combined with data from
OPP's registration review document for acephate (U.S. EPA 2016). The final chronic propazine
dataset consisted of NOECs/LOEC for seven species (Table 5).

Table 5. Chronic toxicity data of propazine to freshwater aquatic organisms.

(MDR specifies OW minimum data requirements under the Guidelines



OW
M l)K

Species

\oi:c

I.OIX

SMC V

(IMC V

Source

MRID/IX ()T()\

ri:i

Plant

Blue Green Algae
(Anabaena flos-aquae)

68



68

68

OPP/
ECOTOX

44287312/344

D

Water Flea
(Daphnia magna)

47

91

65.40

65.40

OPP/
ECOTOX

44327602 / 344







370





ECOTOX

344

Plant

Duckweed
(Lemna gibba)

22



22

22

OPP/
ECOTOX

44287309 / 344

Plant

Freshwater Diatom
(Navicula pelliculosa)

6.5



6.5

6.5

OPP/
ECOTOX

44287310/344

B

Fathead minnow
(Pimephales promelas)

560

1230

829.9

829.9

OPP

48036205

Plant

Green Algae

(Raphidocelis

subcapitata)

12



12

12

OPP/
ECOTOX

44287308 / 344

C

Western Clawed Frog
(Xenopus tropicalis)

101.7

1036.5

324.7

324.7

ECOTOX

178499

a OW MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important

warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Chronic Benchmark Values

The OPP nonvascular plant benchmark value for propazine is 6.5 |ig/L, which is the NOEC for
N. pelliculosa. The OPP vascular plant benchmark value is 22 |ig/L, which is the NOEC for L.
gibba.

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The OPP invertebrate chronic benchmark value is 47 |ig/L, which is the NOEC for Daphnia
magna.

The OPP fish chronic benchmark value is 560 |ig/L, which is the NOEC for Pimephales
promelas.

GLI Tier II Chronic Value Calculation

Paired quantitative acute and chronic toxicity data were available for the frog Xenopus tropicalis
allowing for the calculation of one ACR. Per the GLI Tier II methodology, the default value of
18 was used to fulfill the remaining two ACRs. The resulting X. tropicalis ACR is 16.01, and the
final SACR is 17.31. Dividing the SAV of 3.100 |ig/L by the SACR of 17.31 results in a
Secondary Continuous Value ofO.1791 |ig/L, and a Secondary Continuous Concentration of 0.18
Hg/L-

Detailed calculations for the SCV are shown below:

SACR = Geometric Mean of the ACRs

SACR = V16.01 * 18 * 18 = 17.13

SCV =

SACR

3.100

5CK = JfJ3 = °-18 w/L

Modified Chronic HCos

The genus-level modified chronic HC05 calculated following the U.S. EPA (1985) methodology
for the four most sensitive genera regardless of taxa (Table 6) in the propazine dataset was 2.3
|ig/L (Table 7).

Table 6. Propazine SMCVs and G

MCVs (jug/L).

(ion us

Species

SMC V

(IMC V

(;m( y

kit nk

OW
MIJR

(iroup

Pimephales

promelas

x:<>

x:<>

"

i:

Xenopus

tropicalis

324.7

324.7

6

c

Anabaena

flos-aquae

68

68

5

Plant

Daphnia

magna

65.40

65.40

4

D

Lemna

gibba

22

22

3

Plant

Raphidocelis

subcapitata

12

12

2

Plant

Navicula

pelliculosa

6.5

6.5

1

Plant

a OW MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important
warmwater species (e.g., bluegill, channel catfish, etc.)

235


-------
C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

Table 7. Modified chronic HCos for propazine calculated following the U.S. EPA (1985)

N

Rank

GMCV

ln(GMCV)

ln(GMCV)2

P=R/(N+1)

sqrt(P)

1

4

65.40

4.181

17.48

0.5000

0.7071



3

22

3.091

9.55

0.3750

0.6124



2

12

2.485

6.17

0.2500

0.5000



1

6.5

1.872

3.50

0.1250

0.3536



Sum:



11.63

36.7

1.250

2.173







S2 =

41.82

L =

-0.606

A =

0.840

FCV =

2.316

ccc=

2.3

Table 8. Summary and comparison of chronic values for propazine.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison.			

Pesticide

Most Sensitive OPP ALB
(Year published and species)

OW GLI Tier II value
(# of ACRs filled,
magnitude relative to ALB)

OW Modified HCos
(# of MDRs filled, # of genera
available, magnitude relative to ALB)

Propazine

6.5 ng/L

(2022; Naviculapelliculosa;
nonvascular plant)

0.18 ng/L

(GLI Tier II; 1 ACR filled,

36X)

2.3 ng/L

(3 MDRs, 7 genera, 2.8X)

Figure 2 shows a chronic genus-level sensitivity distribution for the propazine dataset. Major
taxonomic groups are delineated by different symbols. Lines denoting the OPP chronic
benchmark values, GLI Tier II calculated chronic value, and modified HCos value are included.

236


-------
10,000

1,000

01
C

•

N

ro

Q.

O

100

10

Amphibian
Fish

Invertebrate
Nonvascular plant
Vascular plant
-Modified HC05
GLI Tier II

Nonvascular Plant ALB
Vascular Plant ALB

Navicula

Lemna



"KapHicfocefis"

+ Daphnia

t

Anabaena

Pimephales A
~ Xenopus

Vascular Plant ALB = 22 pg/L

^ i\avicuia *

Nonvascular Plant ALB = 6.5 pg/L

Modified HC05 =2.3 pg/L

1 -

GLI Tier II = 0.18 pg/L

	1	1	

0.8	0.9

0.0

0.1

0.2

0.3	0.4	0.5	0.6

Chronic Sensitivity Centile

0.7

1.0

Figure 2. Propazine genus-level chronic SD.

Symbols represent Genus Mean Chronic Values (GMCVs) calculated using all available data from an Office of Water ECOTOX
search in 2021 and the Office of Pesticide Programs (OPP) registration review document for propazine (U.S. EPA 2016).

237


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2.1.2.3 Propazine References

MRID 34123. Woodard Research Corporation. 1980. Propazine Acute Toxicity in Rainbow
Trout 2402-094-03/0003 33-5-C.

MRID 44287308. Hicks, S.L., J.B. Bussard, and D.W. Gledhill. 1995. Acute toxicity to
propazine to Selenastrum capricornutum Printz. Unpublished study conducted by ABC
Laboratories, Columbina, Missouri. Final Report No 41962. Study sponsored by Griffin
Corporation, Valdosta, GA. Study completed April 19, 1995.

MRID 44287309. Hicks, S.L., D.W. Gledhill, and J. Veltri. 1995. 14-day Statis Toxicity of
Propazine to Lemna gibba G3. Unpublished study conducted by ABC Laboratories, Inc.
Columbia, Missouri. Final report No 41963. Sponsored by Griffin Corporation, Valdosta, GA.
Study completed May 24, 1995.

MRID 44287310. Hicks, S.L. and D.W. Gledhill. 1995. Acute toxicity of propazine toNavicula
pelliculosa. Unpublished study conducted by ABC Laboratories, Inc., Columbia, Missouri. Final
Report No. 41966. Study sponsored by Griffin Corporation, Valdosta, GA. Study completed
August 30, 1995.

MRID 44287312. Gledhill, D.W., and J.M. Bussard, 1995. Acute toxicity of propazine to
Anabaena flos-aquae. Unpublished study conducted by ABC Laboratories, Inc. Columbia,
Missouri. Report No. 41968. Sponsored by Griffin Corporation, Valdosta, GA. Study completed
May 22, 1995.

MRID 44327602. Murrell, H.R. and J.L. Veltri. 1997. Chronic toxicity of propazine to Daphnia
magna under flow-through test conditions. Unpublished study conducted by ABC Laboratories,
Inc, Columbia, Missouri. Amended final report No. 41958. Study sponsored by Griffin
Corporation, Valdosta, GA. Study completed July 3, 1997.

MRID 47452301. Bergfield, A. 2008. Propazine: Acute Toxicity to the Rainbow Trout,
Oncorhynchus mykiss, Determined Under Static Test Conditions. Unpublished study performed
by ABC Laboratories, Inc., Missouri, USA. Laboratory report number 63222. Study sponsored
by Albaugh,Inc. Study completed on June 13, 2008.

MRID 48036203. Bergfield, A. 2009. Propazine: Acute toxicity to the Bluegill Sunfish, Lepomis
macrochirus, determined under flow-through test conditions. Unpublished study performed by
ABC Laboratories, Inc., Columbia, Missouri. Laboratory Study No. 64353. Study sponsored by
Albaugh, Inc., Valdosta, Georgia. Study completed April 30, 2009.

MRID 48036205. Lehman, C. 2009. Propazine: Early life-stage toxicity test with the Fathead
Minnow, Pimephales promelas, under flow-through conditions. Unpublished study conducted by
ABC Laboratories, Columbia, Missouri. ABC Study No. 64354. Study sponsored by Albaugh,
Inc., Valdosta, GA. Study completed June 29, 2009.

Saka, M., N. Tada, and Y. Kamata. Chronic Toxicity of 1,3,5-Triazine Herbicides in the
Postembryonic Development of the Western Clawed Frog Silurana tropicalis. Ecotoxicol.
Environ. Saf 147:373-381, 2018. ECOREF #178499.

238


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U.S. Environmental Protection Agency. Pesticide Ecotoxicity Database (Formerly:
Environmental Effects Database (EEDB)). Environmental Fate and Effects Division, U.S.EPA,
Washington, D.C., 1992. ECOREF #344.

U.S. EPA. 2024. Draft Comparison of Aquatic Life Protective Values Developed for Pesticides
under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and
the Clean Water Act (CWA). EPA-820-D-24-002.

239


-------
2.1.3 Comparison of Aquatic Life Toxicity Values for Simazine: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
('CWA) (U.S. EPA 2024) were obtained from the Office of Pesticide Programs (OPP) registration
review document for simazine (U.S. EPA 2016) and an EPA ECOTOX Knowledgebase search
conducted in 2021.

2.1.3.1 Simazine Acute Toxicity Data

Acute data for simazine are shown in Table 1. Ranked invertebrate GMAVs from all data
sources are listed in Table 2.

Table 1. Acute toxicity data of simazine to freshwater aquatic organisms.

MDR specifies OW minimum data requirements under the Guidelines.)

OW
MI)Ra

Species

IX 50

S\1 AY

<;may

Source

MRU) / l-X'OTOX
ri:i

Plant

Anabaena flos-aquae

36

36

36

ECOTOX

344

Plant

Arthrospira platensis

6

6

6

OPP

E17259

G

Branchiura sowerbyi

1,090,000

1,588,201

1,588,201

ECOTOX

70292





1,700,000





ECOTOX

70292





1,897,000





ECOTOX

70292





1,810,000





ECOTOX

70292

B

Carassius auratus

>32,000

>32000

>32000

OPP/
ECOTOX

344

B

Cirrhinus mrigala

765,000

820,378

820,378

ECOTOX

70292





1,050,000





ECOTOX

70292





1,100,000





ECOTOX

70292





895,000





ECOTOX

70292





840,000





ECOTOX

70292





608,000





ECOTOX

70292





635,000





ECOTOX

70292





800,000





ECOTOX

70292

E

Cypridopsis vidua

3700

3,700

3,700

OPP

4009801

D

Daphnia magna

1,000

>10192

>153213

OPP

45088221





1,100





OPP

4009801





>10,000





ECOTOX

6797





>10,000





ECOTOX

6797





>1,000,000





ECOTOX

89626

D

Daphnia pulex

424,000

153,213



ECOTOX

2897





92,100





ECOTOX

2897





92,100





ECOTOX

11881

E

Gammarus fasciatus

130,000

130,000

130,000

OPP/
ECOTOX

4009801/6797

E

Hyalella azteca

270,000

270,000

270,000

ECOTOX

89626

240


-------
()\\
MDR-

Species

IX 50

S\1 AY

<;may

Source

MRU) / l-X'OTOX
ri:i

Plant

Lemna gibba

140

140

152.4

OPP/
ECOTOX

42503704 / 344

Plant

Lemna minor

166

166



ECOTOX

18093





16,000

40,000

40,000

OPP/

25438 or 229607/

B

Lepomis macrochirus

ECOTOX

344





100,000





OPP/
ECOTOX

4009801/6797

C

Lithobates catesbeiana

1,780,000

1,780,000

1,780,000

ECOTOX

89626

B

Morone saxatilis

250

>20,083

>20,083

ECOTOX

909





>180,000





ECOTOX

5324





>180,000





ECOTOX

5324

Plant

Navicula pelliculosa

90

90

90

OPP/
ECOTOX

42503707 / 344

A

Oncorhynchus kisutch

330,000

330,000

>264441

ECOTOX

89626

A

Oncorhynchus mykiss

60,000

>61579



ECOTOX

344





40,500





ECOTOX

344





>10,000





ECOTOX

344





>82,000





ECOTOX

344





70,500





ECOTOX

344





44,600





ECOTOX

344





>100,000





ECOTOX

6797





330,000





ECOTOX

89626

A

Oncorhynchus
tshawytscha

910,000

910,000



ECOTOX

89626

E

Pacifastacus leniusculus

30,600

30,600

30,600

ECOTOX

167249

E

Palaemonetes
kadiakensis

>5,600

>5600

>5600

OPP

4009801

B

Pimephales promelas

6,400

>31958

>31958

OPP/
ECOTOX

33309/344





>10,000





ECOTOX

6797





510,000





ECOTOX

6797

F

Pteronarcys californica

1,900

1,900

1,900

OPP/
ECOTOX

4009801/6797

Plant

Raphidocelis subcapitata

100

232.1

232.1

OPP/
ECOTOX

42503706 / 344





200





ECOTOX

16010





100





ECOTOX

17639





1,240





ECOTOX

18093





100





ECOTOX

56747





200





ECOTOX

69584





220





ECOTOX

69584





220





ECOTOX

69584





748.5





ECOTOX

83543





252





ECOTOX

165277

Plant

Selenastrum sp.

73.6

58.96

58.96

ECOTOX

84045

241


-------
OW
MDR'

Species

IX 50

S\1 AY

<;may

Source

MRU) / l-X'OTOX
ri:i





57.3





ECOTOX

84045





48.6





ECOTOX

84045

Plant

Vallisneria americana

67

67

67

OPP/
ECOTOX

E164763 / 164763

G

Viviparus bengalensis

2,280,000

1,671,145

1,671,145

ECOTOX

70292





1,676,000





ECOTOX

70292





986,000





ECOTOX

70292





2,070,000





ECOTOX

70292

C

Xenopus tropicalis

7,550

7,550

7,550

ECOTOX

178499

a OW MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important

warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Acute Benchmark Values

The OPP nonvascular plant benchmark value for simazine is 6 |ig/L, which is the LC50 for A.
platensis. The OPP vascular plant benchmark value is 67 |ig/L, which is the LC50 for V.
americana.

The OPP invertebrate acute benchmark value is 500 |ig/L, which is V2 the LC50 for D. magna.
The OPP fish acute benchmark value is 3,200 |ig/L, which is V2 the LC50 fori5, promelas.

OW Acute Criterion

There is no criterion maximum concentration (CMC) for simazine. An illustrative example
calculated was developed for this analysis, using all available data (Table 2). The Final Acute
Value (FAV) calculated following the U.S. EPA (1985) methodology for the 22 genera in the
simazine dataset was 10.36 |ig/L (Table 3).

Table 2. Simazine SMAVs and <

jMAVs (jug/L).

(ienus

Species

SMAV

(IMAY

(;may

R;ink

ONY
MDR

(J roup

liana

catesbeiana

1,780,000

1,780,000

22

C

Viviparus

bengalensis

1,671,145

1,671,145

21

G/H

Branchiura

sowerbyi

1,588,201

1,588,201

20

G

Cirrhinus

mrigala

820,378

820,378

19

B

Hyalella

azteca

270,000

270,000

17

E

242


-------
(ion us

Species

S\1 AY

(IMAY

(IMAY
kiink

OW
M l)K

(J roup

Oncorhynchus

kisutch

330,000

>264,441

17

A

Oncorhynchus

mykiss

>61,597





A

Oncorhynchus

tshawytscha

910,000





A

Gammarus

fasciatus

130,000

130,000

16

E

Lepomis

macrochirus

40,000

40,000

15

B

Daphnia

magna

>10,192

>39,517

14

D

Daphnia

pulex

153,213





D

Carassius

auratus

>32,000

>32,000

13

B

Pimephales

promelas

>31,958

>31,958

12

B

Pacifastacus

leniusculus

30,600

30,600

11

E

Morone

saxatilis

20,083

20,083

10

B

Xenopus

tropicalis

7,550

7,550

9

C

Palaemonetes

kadiakensis

>5,600

>5,600

8

E

Cypridopsis

vidua

3,700

3,700

7

E

Pteronarcys

spp

1,900

1,900

6

F

Lemna

gibba

140

140

5

Plant

Raphidocelis

subcapitata

100

100

4

Plant

Navicula

pelliculosa

90

90

3

Plant

Vallisneria

americana

67

67

2

Plant

Arthrospira

platensis

6

6

1

Plant

a OW MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important
warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

243


-------
Table 3. Genus-level acute HCos for simazine calculated following the U.S. EPA (1985)
methodology.

N

Rank

GMAV

ln(GMAV)

ln(GMAV)2

P=R/(N+1)

sqrt(P)

22

4

100

4.605

21.21

0.1739

0.4170



3

90

4.500

20.25

0.1304

0.3612



2

67

4.205

17.68

0.0870

0.2949



1

6

1.792

3.21

0.0435

0.2085



Sum:



15.10

62.3

0.435

1.282







S2 =

220.64

L =

-0.984

A =

2.338

FAV =

10.36

CMC =

5.18

Table 4. Summary and comparison of acute values for simazine.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

Pesticide

Most Sensitive OPP ALB
(Year published, species)

OW Illustrative ALC
example
(# of MDRs filled,
magnitude relative to
ALB)

OW Modified HCos
(# of MDRs filled,
# of genera available,
magnitude relative to
ALB)

Simazine1

6 (ig/L

(2023; Arthrospira
platensis; nonvascular plant)

5.2 (ig/L

(illustrative example
calculated for this analysis; 8
MDRs filled, 1.2X)

NA

'No 304(a) ALC recommendation available but has sufficient data to develop an illustrative ALC example for the purposes of
these analyses only.

Figure 1 shows a genus-level sensitivity distribution for the simazine dataset. Major taxonomic
groups are delineated by different symbols, and invertebrate genera are identified by name. Lines
denoting the OPP acute benchmark values and the illustrative OW ALC example.

244


-------
10,000,000

1,000,000

100,000

~	Amphibian
O Fish

A Insect
A Invertebrate
+ Mollusk

•	Nonvascular plant
¦ Vascular plant

	• (FAV/2) - ALC (illustrative example calculated for this analysis)

Nonvascular Plant ALB
....... vascular Plant ALB

A + ~

O

O A

A O O

A O

<. 10,000

cm
m

c 1,000
re

,1

^ 100

A

- Raphidocelis

r Selenastrum B		Lemna

Navicula



10

¦L

- Anabaena
Arthrospira

Vallisneria

Vascular Plant ALB = 67 pg/L

Nonvascular Plant ALB = 6 pg/L

(FAV/2) - ALC {illustrative example calculated for this analysis) = 5.1...

0.0	0.1	0.2	0.3	0.4	0.5	0.6	0.7

Acute Sensitivity Centile

0.8

0.9

1.0

Figure 1. Simazine genus-level acute SD.

Symbols represent Genus Mean Acute Values (GMAVs) calculated using all available data from an Office of Water ECOTOX search
in 2021 and the Office of Pesticide Programs (OPP) registration review document for simazine (U.S. EPA 2016).

245


-------
2.1.3.2 Simazine Chronic Toxicity Data
Data Sources and Considerations

Chronic toxicity data for simazine were consolidated by OW and combined with data from
OPP's registration review document for acephate (U.S. EPA 2016). The final chronic simazine
dataset consisted of NOECs/LOEC for 15 species (Table 5).

Table 5. Chronic toxicity data of simazine to freshwater aquatic organisms.

(MDR s

necifies OW minimum data requirements under the Guidelines



OW
MIJR

Scientific

\oi:c

LOIX

SMC V

(IMC V

Source

Mkii)

Plain

_ 1rthrospira plalensis

l( ()5 | o



1

1

OH'

i:r:5<>

B

Cyprinus carpio

60

600

189.7

189.7

OPP/
ECOTOX

Velisek et al 2012
/197125

B

Danio rerio

60



60

60

ECOTOX

167124

D

Daphnia magna





40

40

OPP

43676





40







OPP

based on ACR

Plant

Lemna gibba

50

110

50

61.24

OPP/
ECOTOX

42503704 / 344

Plant

Lemna minor

75

150

75



ECOTOX

18093

Plant

Myriophyllum
aquaticum

50

1,500

50

50

ECOTOX

68622

Plant

Navicula pelliculosa

30

70

30

30

OPP/
ECOTOX

42503707 / 344

B

Pimephales promelas

960

2000

1,386

1,386

OPP

43675

Plant

Pontederia cordata

300

1,000

300

300

ECOTOX

59738

Plant

Raphidocelis
subcapitata

93.2

>93.2

85.60

85.60

OPP

49389101





30

70





OPP/
ECOTOX

42503706 / 344





600

1,200





ECOTOX

18093





32

100





ECOTOX

165277

Plant

Typha latifolia

300

1000

300

300

ECOTOX

57010

Plant

Vallisneria americana

<58

<58

<58

<58

OPP/
ECOTOX

E164763 / 164763

C

Xenopus laevis

1.2

11

3.633

30.87

ECOTOX

178652

C

Xenopus tropicalis

83

828.5

262.2



ECOTOX

178499

a OW MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important

warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

246


-------
OPP Chronic Benchmark Values

The OPP nonvascular plant benchmark value for simazine is 1 |ig/L, which is the NOEC for
Arthrospiraplatensis. The OPP vascular plant benchmark value is 67 |ig/L, which is the NOEC
for L. gibba.

The OPP invertebrate chronic benchmark value is 40 |ig/L, which is the estimated NOEC for
Daphnia magna (LC50 (rounded to 1,000 ug/L) divided by D. magna atrazine ACR of 25).

The OPP fish chronic benchmark value is 60 |ig/L, which is the NOEC for C. carpio.

GLI Tier II Chronic Value Calculation

Paired quantitative acute and chronic toxicity data were available for Pimephalespromelas and
Xenopus tropicalis allowing for the calculation of two ACRs. Per the GLI Tier II methodology,
the default value of 18 was used to fulfill the remaining one ACR. The resulting ACRs for X
tropicalis is 28.79 and I\ promelas is 4.618, and the final SACR is 13.38. Dividing the SAV of
10.36 |ig/L by the SACR of 13.38 results in a Secondary Continuous Value of 0.7742 |ig/L, and
a Secondary Continuous Concentration of 0.77 |ig/L.

Detailed calculations for the SCV are shown below:

SACR = Geometric Mean of the ACRs

SACR = V28.79 * 4.618 * 18 = 13.38

10.36

5CK = = °-7742 M/L

Modified Chronic HCos

The genus-level modified chronic HCos calculated following the U.S. EPA (1985) methodology
for the four most sensitive genera regardless of taxa (Table 6) in the simazine dataset was 0.8
|ig/L (Table 7).

Table 6. Simazine SMCVs and GMCVs

(Hg/L).

(Ionus

Species

SMC V

(IMC V

(;m( y

kiink

()\\
MIJR

(iroup

Pimephales

promelas

1,386

1,386

13

B

Typha

latifolia

300.0

300.0

12

Plant

Pontederia

cordata

300.0

300.0

11

Plant

Cyprinus

carpio

189.7

189.7

10

B

Danio

rerio

60

60

9

B

Daphnia

magna

40

40

8

D

Raphidocelis

subcapitata

85.60

85.60

7

Plant

Lemna

gibba

50

61.24

6

Plant

247


-------
(ionus

Species

S\l( V

(IMC A

(;m( y

k:in k

OW
M l)K

(iroup

Lemna

minor

75





Plant

Vallisneria

americana

<58

<58

5

Plant

Myriophyllum

aquaticum

50

50

4

Plant

Xenopus

laevis

3.633

30.87

3

C

Xenopus

tropicalis

262.2





C

Navicula

pelliculosa

30

30

2

Plant

Arthrospira

platensis

1

1

1

Plant

a OW MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important
warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

Table 7. Modified chronic HCos for propazine calculated following the U.S. EPA (1985)
methodology.

.V

Kiink

(;\K \

Iim(;\i( \ t

|ik(;mcy):

l*=K/( N+l)

MII-IlP)

13

4

40

3.689

13.61

0.2857

0.5345



3

30.87

3.430

11.76

0.2143

0.4629



2

30

3.401

11.57

0.1429

0.3780



1

1

0.000

0.00

0.0714

0.2673



Sum:



10.52

36.9

0.714

1.643







S2 =

233.54

L =

-3.646

A =

-0.229

FCV =

0.7956

ccc=

0.80

248


-------
Table 8. Comparison and summary of chronic values for simazine.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for

each value comparison. A ratio >1 indicates the 0

3P value is higher than the OW value.

Pesticide

Most Sensitive OPP ALB
(Year published and

species)

OW GLI Tier II value

(# of ACRs filled,
magnitude relative to
ALB)

OW Modified HCos
(# of MDRs filled, # of

genera available,
magnitude relative to
ALB)

Simazine

1 (ig/L

(Arthrospira platensis;
nonvascular plant)

0.77 jig/L

(GLI Tier II; 2 ACRs
filled, 1.3X)

0.8 (ig/L

(3 MDRs, 13 genera,
1.3X)

Figure 2 shows a chronic genus-level sensitivity distribution for the simazine dataset. Major
taxonomic groups are delineated by different symbols. Lines denoting the OPP chronic
benchmark values, GLI Tier II calculated chronic value, and modified HCos value are included.

249


-------
10,000

1,000

^ 100

00

3

01

c

*N 10
(B

£

In

1 .

Amphibian
Fish

Invertebrate
Nonvascular plant
Vascular plant
¦ Modified HC05
GLI Tier II

Vascular Plant ALB

V

~

Navicula

Arthrospira

+

^-Typha |

~

Pontederia

r Lemna

ir	w	

Myriophyllum

Vallisneria (non-definitive, less than value)

Raphidocelis

Vascular Plant ALB = 58 pg/L

Modified HC05 =0.80 pg/L

~i	r

0.8	0.9

0.0

0.1

0.2

0.3	0.4	0.5	0.6	0.7

Chronic Sensitivity Centile

1.0

Figure 2. Simazine genus-level chronic SD.

Symbols represent Genus Mean Chronic Values (GMCVs) calculated using all available data from an Office of Water ECOTOX
search in 2021 and the Office of Pesticide Programs (OPP) registration review document for propazine (U.S. EPA 2016).

250


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2.1.3.3 Simazine References

MRID 42503704. Thompson, S.G. 1992. A 14-day toxicity test with duckweed (Lemna gibba
G3). Unpublished study conducted by Wildlife International, Ltd, Easton, MD. Laboratory
Report No. 108A-137. Study sponsored by Agricultural Division, Ciba-Geigy Corporation,
Greensboro, NC.

MRID 42503706. Thompson, S.G. 1992. A 5-day toxicity test with the freshwater alga
(Selenastrum capricornutum). Unpublished study conducted by Wildlife Internationa, Ltd.,
Easton, MD. Laboratory study number 108A-141. Study sponsored by Agricultural Division
Ciba-Geigy Corporation, Greensboro, NC. Study completed September 10, 1992.

MRID 42503707. Thompson, S.G. 1992. A 5-day toxicity test with the freshwater diatom
(Navicular pelliculosa). Unpublished study conducted by Wildlife International, Easton, MD.
Laboratory study number 108A-138. Study sponsored by Agricultural Division, Ciba-Geigy
Corporation, Greensboro, NC. Study completed September 11, 1992.

MRID 43676. Mayer, F.L. and M.D. Sander. 1981. Effects of Atrazine Fathead Minnow under...
Unpublished study conducted by Fish-Pesticide Research Laboratory, Fish and Wildlife Service,
Columbia, Missouri.

MRID 49389101. Grade, R. 1999. Growth Inhibition Test of G 30414 to Green Algae
(Selenastrum capricornutum) under Static Conditions. Final Report. Unpublished study
conducted by Novartis Crop Protection AG, Basel, Switzerland. Report Number 991589. Study
sponsored by Syngenta Crop Protection LLC, Greensboro, NC. Study completed on November
16, 1999.

Abdel-Hamid, M.I. 1996. Development and Application of a Simple Procedure for Toxicity
Testing Using Immobilized Algae. Water Sci. Technol. 33(6): 129-138.
doi: 10.2166/wst. 1996.0089. ECOREF #69584.

Bednarz, T. (1981). The Effect of Pesticides on the Growth of Green and Blue-Green Algae
Cultures. Acta Hydrobiol., 23, (2), 155-172. ECOREF#:17259

Carter, J.G. 1981. Effects of the Herbicide Simazine upon Production in a Two Member Aquatic
Food Chain. Ph.D. Thesis, Utah State University, Logan, UT:213 p. ECOREF #70902.

Fairchild, J.F., D.S. Ruessler, P.S. Haverland, and A.R. Carlson. 1997. Comparative Sensitivity
of Selenastrum capricornutum and Lemna minor to Sixteen Herbicides. Arch. Environ. Contam.
Toxicol., 32, (4), 353-357. doi:10.1007/s002449900196. ECOREF #18093.

Fairchild, J.F., D.S. Ruessler, P.S. Haverland, and A.R. Carlson. 1997. Comparative Sensitivity
of Selenastrum capricornutum and Lemna minor to Sixteen Herbicides. Arch. Environ. Contam.
Toxicol. 32(4): 353-357. doi:10.1007/s002449900196. ECOREF #18093.

Fairchild, J.F., D.S. Ruessler, P.S. Haverland, and A.R. Carlson. 1997. Comparative Sensitivity
of Selenastrum capricornutum and Lemna minor to Sixteen Herbicides. Arch. Environ. Contam.
Toxicol. 32(4): 353-357. doi:10.1007/s002449900196. ECOREF #18093.

Fitzmayer, K.M., J.G. Geiger, and M.J. Van den Avyle. 1982. Acute Toxicity Effects of
Simazine on Daphniapulex and Larval Striped Bass. Proc. Annu. Conf. Southeast. Assoc. Fish
Wildl. Agencies36:146-156. ECOREF #2897.

251


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Fitzmayer, K.M., J.G. Geiger, and M.J. Van den Avyle. 1982. Effects of Chronic Exposure to
Simazine on the Cladoceran, Daphniapulex. Arch. Environ. Contam. Toxicol. 11(5): 603-609.
ECOREF #11881.

Kallqvist, T., and R. Romstad. 1994. Effects of Agricultural Pesticides on Planktonic Algae and
Cyanobacteria — Examples of Interspecies Sensitivity Variations. Norw. J. Agric. Sci. Suppl. 13:
117-131. ECOREF #16010.

Kamaya, Y., T. Takada, and K. Suzuki. 2004. Effect of Medium Phosphate Levels on the
Sensitivity of Selenastrum capricornutum to Chemicals. Bull. Environ. Contam. Toxicol. 73(6):
995-1000. doi: 10.1007/sOO 128-004-0524-8. ECOREF #84045.

Knuteson, S.L., T. Whitwell, and S.J. Klaine. 2002. Influence of Plant Age and Size on Simazine
Toxicity and Uptake. J. Environ. Qual. 31(6): 2096-2103. ECOREF #68622.

Ma, J., S. Wang, P. Wang, L. Ma, X. Chen, and R. Xu. 2006. Toxicity Assessment of 40
Herbicides to the Green Alga Raphidocelis subcapitata. Ecotoxicol. Environ. Saf. 63(3): 456-
462. doi: 10.1016/j.ecoenv.2004.12.001. ECOREF #83543.

Mayer, F.L., Jr., and M.R. Ellersieck. 1986. Manual of Acute Toxicity: Interpretation and Data
Base for 410 Chemicals and 66 Species of Freshwater Animals. USDI Fish and Wildlife Service,
Publication No.160, Washington, DC:505 p. ECOREF #6797.

McCann, J.A., and R.K. Hitch. 1980. Simazine Toxicty to Fingerling Striped Bass. Prog. Fish-
Cult. 42(3): 180-181. ECOREF #5324.

Okamura, H., I. Aoyama, D. Liu, R.J. Maguire, G.J. Pacepavicius, and Y.L. Lau. 2000. Fate and
Ecotoxicity of the New Antifouling Compound Irgarol 1051 in the Aquatic Environment. Water
Res. 34(14): 3523-3530. doi:10.1016/S0043-1354(00)00095-6. ECOREF #56747.

Perez, J., I. Domingues, A.M.V.M. Soares, and S. Loureiro. 2011. Growth Rate of
Pseudokirchneriella subcapitata Exposed to Herbicides Found in Surface Waters in the Alqueva
Reservoir (Portugal): A Bottom-up Approach Using Binary Mixtures. Ecotoxicology 20(6):
1167-1175. doi: 10.1007/s 10646-011-0661-x. ECOREF #165277.

Perez, J., I. Domingues, A.M.V.M. Soares, and S. Loureiro. 2011. Growth Rate of
Pseudokirchneriella subcapitata Exposed to Herbicides Found in Surface Waters in the Alqueva
Reservoir (Portugal): A Bottom-up Approach Using Binary Mixtures. Ecotoxicology 20(6):
1167-1175. doi:10.1007/s 10646-011-0661-x. ECOREF #165277.

Plhalova, L., I. Haluzova, S. Macova, P. Dolezelova, E. Praskova, P. Marsalek, M. Skoric, Z.
Svobodova, V. Pistekova, an. 2011. Effects of Subchronic Exposure to Simazine on Zebrafish
(Danio rerio). Neuroendocrinol. Lett. 32(Suppl. 1): 89-94. ECOREF #167124.

Sai,L., Y. Liu, B. Qu, G. Yu, Q. Guo, C. Bo, L. Xie, Q. Jia, Y. Li, X. Li, J.C. Ng, and C. Peng.
2015. The Effects of Simazine, a Chlorotriazine Herbicide, on the Expression of Genes in
Developing Male Xenopus laevis. Bull. Environ. Contam. Toxicol. 95(2): 157-163. ECOREF
#178652.

Saka, M., N. Tada, and Y. Kamata. 2018. Chronic Toxicity of 1,3,5-Triazine Herbicides in the
Postembryonic Development of the Western Clawed Frog Silurana tropicalis. Ecotoxicol.
Environ. Saf. 147: 373-381. ECOREF #178499.

252


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U.S. Environmental Protection Agency. 1992. Pesticide Ecotoxicity Database (Formerly:
Environmental Effects Database (EEDB)). Environmental Fate and Effects Division, U.S.EPA,
Washington, D.C., 1992. ECOREF #344.

U.S. Environmental Protection Agency. 2024. Draft Comparison of Aquatic Life Protective
Values Developed for Pesticides under the Federal Insecticide, Fungicide, and Rodenticide Act
(FIFRA) and the Clean Water Act (CWA). EPA-820-D-24-002.

Velisek, J., A. Kouba, and A. Stara. 2013. Acute Toxicity of Triazine Pesticides to Juvenile
Signal Crayfish (Pacifastacus leniusculus). Neuroendocrinol. Lett.34(2): 31-36. ECOREF
#167249.

Velisek, J., A. Stara, J. Machova, and Z. Svobodova. 2012. Effects of long-term exposure to
simazine in real concentrations on common carp (Cyprinus carpio L). Ecotoxicol. Environ. Saf.
76: 79-86.

Versteeg, D.J. 1990. Comparison of Short- and Long-Term Toxicity Test Results for the Green
Alga, Selenastrum capricornutum. ASTM Spec. Tech. Publ., 40-48. ECOREF #17639.

Wan, M.T., C. Buday, G. Schroeder, J. Kuo, and J. Pasternak. 2006. Toxicity to Daphnia magna,
Hyalella azteca, Oncorhynchus kisutch, Oncorhynchus mykiss, Oncorhynchus tshawytscha, and
Rana catesbeiana of Atrazine, Metolachlor, Simazine, and Their Formulated Products. Bull.
Environ. Contam. Toxicol. 76(1): 52-58. doi:10.1007/s00128-005-0888-4. ECOREF #89626.

Wilson, P.C., and S.B. Wilson. 2010. Toxicity of the Herbicides Bromacil and Simazine to the
Aquatic Macrophyte, Vallisneria americana Michx. Environ. Toxicol. Chem. 29(1): 201-211.
doi:10.1002/etc.22. ECOREF #164763.

Wilson, P.C., and S.B. Wilson. 2010. Toxicity of the Herbicides Bromacil and Simazine to the
Aquatic Macrophyte, Vallisneria americana Michx. Environ. Toxicol. Chem. 29(1): 201-211.
ECOREF #164763.

Wilson, P.C., T. Whitwell, and S.J. Klaine. 2000. Metalaxyl and Simazine Toxicity to and
Uptake by Typha latifolia. Arch. Environ. Contam. Toxicol. 39(3): 282-288. ECOREF #57010.

Wilson, P.C., T. Whitwell, and S.J. Klaine. 2000. Phytotoxicity, Uptake, and Distribution of
14C-Simazine in Acorus gramenius and Pontederia cordata. Weed Sci. 48: 701-709. ECOREF
#59738.

253


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2.1.4 Comparison of Aquatic Life Toxicity Values for Bensulide: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
('CWA) (U.S. EPA 2024) were obtained from the Office of Pesticide Programs (OPP) registration
review document for bensulide (U.S. EPA 2016) and an EPA ECOTOX Knowledgebases search
conducted in 2021.

2.1.4.1 Bensulide Acute Toxicity Data

Acute data for bensulide are shown in Table 1. Ranked invertebrate GMAVs from all data
sources are listed in Table 2.

Table 1. Acute toxicity data of bensulide to freshwater aquatic organisms.

MDR specifies OW minimum data requirements under the Guidelines.)

OW
Ml)k'

Scientific

I X 50

SM AY

(;ma\

Source

MRID/I-X ()T()\
r i: i

Plant

Blue green algae
(Anabaena flos-aquae)

>3,580

>3580

>3580

OPP/
ECOTOX

44720403 / 344

D

Water Flea (Daphnia
magna)

580

580

580

OPP

159322

E

Scud (Gammarus
fasciatus)

1,400

1,400

1,400

OPP/
ECOTOX

40098001/6797

Plant

Duckweed (Lemna gibba)

160

149.7

149.7

OPP/
ECOTOX

45334101 /344





140





OPP/
ECOTOX

44720406 / 344

B

Bluegill (Lepomis
macrochirus)

1,400

1065

1065

OPP/
ECOTOX

157316/344





810





OPP/
ECOTOX

40098001/6797

Plant

Diatom (Navicula
pelliculosa)

<690

<690

<690

ECOTOX

344

A

Rainbow trout
(Oncorhynchus mykiss)

1,100

889.9

889.9

OPP/
ECOTOX

157315/344





720





OPP/
ECOTOX

40098001/6797

Plant

Green algae

(Raphidocelis

subcapitata)

1800

1800

1800

OPP/
ECOTOX

44720402 / 344

Plant

Diatom (Skeletonema
costatum)

780

780

780

OPP

44720405

a OW MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important

warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

254


-------
OPP Acute Benchmark Values

The OPP vascular plant benchmark value for bensulide is 140 |ig/L, which is the LC50 for L.
gibba. The OPP nonvascular plant benchmark value is 780 |ig/L, which is the LC50 for S.
costatum.

The OPP invertebrate acute benchmark value is 290 |ig/L, which is V2 the LC50 of 580 |ig/L for
D. magna.

The fish acute benchmark value is 550 |ig/L, which is V2 the LC50 of 1,100 |ig/L for 0. mykiss.
GLI Tier II Acute Value Calculation

The acceptable acute dataset for bensulide fulfills four of the eight MDRs, corresponding to the
use of a Secondary Acute Factor (SAF) of 7. Applying the SAF to the lowest, most sensitive
GMAV regardless of taxa (i.e., 149.7 |ig/L for duckweed (Lemna gibba)), the calculated
Secondary Acute Value (SAV) is 21.39 |ig/L. The Secondary Maximum Criterion (SMC), which
is calculated as half the SAV, is 10.7 |ig/L. Detailed calculations for the SMC are shown below:

Lowest GMAV

149.7

SAV = —— = 21.39 |xg/L
SAV

SMC =	

2

21.39

SMC =—— = 10.7 [ig/L

Modified Acute HC05

The genus-level modified acute HC05 calculated following the U.S. EPA (1985) methodology for
the four most sensitive genera regardless of taxa (Table 2) in the bensulide dataset was 106.4
|ig/L (Table 3).

Table 2. Bensulide S

MAVs and GMAVs (ng/L).

(Ion us

Species

S\1 AY

(IMAY

(IMAY
k:iiik

(>\Y MDR

(iroup

Anabaena

Jlos-aquae

>3,580

>3,580

9

Plant

Raphidocelis

subcapitata

1,800

1,800

8

Plant

Gammarus

fasciatus

1,400

1,400

7

E

Oncorhynchus

mykiss

1,100

1,100

6

A

Lepomis

macrochirus

1,065

1,065

5

B

Skeletonema

costatum

780

780

4

Plant

255


-------
Genus

Species

SMAV

GMAV

GMAV
Rank

OW MDR
Group

Navicula

pelliculosa

<690

<690

3

Plant

Daphnia

magna

580

580

2

D

Lemna

gibba

149.7

149.7

1

Plant

a OW MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important
wannwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

Table 3. Modified acute HCos for bensulide calculated following the U.S. EPA (1985)

N

Rank

GMAV

ln(GMAV)

ln(GMAV)2

P=R/(N+1)

sqrt(P)

9

4

780

6.659

44.35

0.4000

0.6325



3

690

6.537

42.73

0.3000

0.5477



2

580

6.363

40.49

0.2000

0.4472



1

149.7

5.009

25.09

0.1000

0.3162



Sum:



24.57

152.6

1.000

1.944







S2 =

31.60

L =

3.410

A =

4.667

FAV =

106.4

CMC =

53.21

Table 4. Comparison and summary of acute values for bensulide.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

Pesticide

OPP Most Sensitive ALB
(Year published, species)

OWGLI Tier II value
(# of MDRs filled, magnitude
relative to ALB)

OW Modified HCW2

(# of MDRs filled,
# of genera available,
magnitude relative to ALB)

Bensulide

140 (ig/L

(2016; Lemna gibba;
vascular plant)

10.7 ng/L

(GLI Tier II; 4 MDRs filled, 13X)

53.21 (ig/L

(4 MDRs, 9 genera, 2.6X)

256


-------
Figure 1 shows a genus-level sensitivity distribution for the bensulide dataset. Major taxonomic
groups are delineated by different symbols. Lines denoting the OPP acute benchmark values,
GLI Tier II calculated acute value, and modified HCos/2 value are included.

257


-------
10,000

1,000

1

~

Fish

H

~

Invertebrate

H

•

Nonvascular plant

J

¦

Vascular plant

j



Modified HC05/2

j

		

GLI Tier II

j

	 , ,

Vascular Plant ALB



	

Invertebrate ALB

¦ Lemna

M

3 100

01

-Q
—

w

Anabaena (non-definitive, greater than value)

V

I

Skeletonema
~

1

^ - Raphidoceiis

Navicula (non-definitive, less than value)

I

Invertebrate ALB = 290 pg/L

.L

Vascular Plant ALB = 140 pg/L

Modified HC05/2 = 53.2 pg/L

m
m

10 T

GLI Tier II = 10,7 pg/L

0.0

0,1

0.2

0.3	0.4	0.5	0.6

Acute Sensitivity Centile

0.7

0.8

0.9

1.0

Figure 1. Bensulide genus-level acute SD.

Symbols represent Genus Mean Acute Values (GMAVs) calculated using all available data from an Office of Water ECOTOX search
in 2021 and the Office of Pesticide Programs (OPP) registration review document for bensulide (U.S. EPA 2016).

258


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2.1.4.2 Bensulide Chronic Toxicity Data
Data Sources and Considerations

Chronic toxicity data for bensulide were consolidated by OW and combined with data from
OPP's registration review document for acephate (U.S. EPA 2016). The final chronic bensulide
dataset consisted of NOECs/LOEC for seven species (Table 5).

Table 5. Chronic toxicity data of bensulide to freshwater aquatic organisms.

MDR specifies OW minimum data requirements under the Guidelines.)

OW
MDR'

Species

\()IX

LOIX

SMC V

(IMC V

Source

MRID/IX ()T()\

ri:i

Plant

Blue green algae

(Anabaena flos-aquae)

3,580



3,580

3,580

OPP/
ECOTOX

44720403 / 344



Water Flea













D

(Daphnia magna)

10.9

16

<7.057

<7.057

OPP

49110401













OPP/







4.2

10





ECOTOX

45303101/344













OPP/







<4.2

4.2





ECOTOX

45063401/344













OPP/







<6.9

6.9





ECOTOX

44720407 / 344













OPP/



Plant

Duckweed (Lemna gibba)

42.8



<42.4

<42.4

ECOTOX

45334101/344













OPP/







<42.1







ECOTOX

44720406 / 344



Diatom (Navicula













Plant

pelliculosa)

<410



<410

<410

ECOTOX

344



Fathead minnow











49378102 and

B

(Pimephales promelas)

200

369

384.2

384.2

OPP

49001601





374

789





OPP

44720408

Plant

Green algae (Raphidocelis
subcapitata)

ECo5=930



930

930

OPP/
ECOTOX

44720402 / 344



Diatom (Skeletonema













Plant

costatum)

635



635

635

OPP

44720405

a OW MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important
warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Chronic Benchmark Values

The OPP vascular plant benchmark value is 42 |ig/L, which is the NOEC for Lemna gibba. The
OPP non-vascular plant benchmark value for bensulide is 635 |ig/L, which is the NOEC for the
diatom (Skeletonema costatum).

259


-------
The OPP invertebrate chronic benchmark for bensulide value is 11 |ig/L, which is the NOEC for
Daphnia magna.

The OPP fish chronic benchmark value is 169 |ig/L, which is the NOEC for Pimephales
promelas.

GLI Tier II Chronic Value Calculation

Paired quantitative acute and chronic toxicity data were available for Daphnia magna allowing
for the calculation of one D. magna ACR of 43.92. Per the GLI Tier II methodology, the default
value of 18 was used to fulfill the remaining two ACRs. The resulting final SACR is 24.23.
Dividing the SAV of 21.39 |ig/L by the SACR of 17.31 results in a Secondary Continuous Value
of 0.8828 |ig/L, and a Secondary Continuous Concentration of 0.88 |ig/L. Detailed calculations
for the SCV are shown below:

SACR = Geometric Mean of the ACRs
SACR = a/43.92 * 18 * 18 = 24.23

SCV =

SACR
21.39

SCV =	= 0.8828 uq/L

24.23

Modified Chronic HCos

The genus-level modified chronic HC05 calculated following the U.S. EPA (1985) methodology
for the four most sensitive genera regardless of taxa (Table 6) in the bensulide dataset was 2.3
|ig/L (Table 7).

Table 6. Bensulide S1V

[CVs and GMCVs (ng/L).

Clonus

Species

SMC V

(IMC V

(IMC V
kiink

MI)R

CI roup

_ 1nabaena

flos-aquae

3,5 SO

3,5 So

"

Plain

Raphidocelis

subcapitata

930a

930a

6

Plant

Skeletonema

costatum

635

635

5

Plant

Navicula

pelliculosa

<410

<410

4

Plant

Pimephales

promelas

368.3

368.3

3

B

Lemna

gibba

<42.4

<42.4

2

Plant

Daphnia

magna

<7.057

<7.057

1

D

a - EC05 (NOAEC not reported)

260


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Table 7. Modified chronic HCos for bensulide calculated following the U.S. EPA (1985)

N

Rank

GMCV

ln(GMCV)

ln(GMCV)2

P=R/(N+1)

sqrt(P)

7

4

410

6.016

36.19

0.5000

0.7071



3

368.3

5.909

34.92

0.3750

0.6124



2

42.4

3.747

14.04

0.2500

0.5000



1

7.057

1.954

3.82

0.1250

0.3536



Sum:



17.63

89.0

1.250

2.173







S2 =

162.60

L =

-2.521

A =

0.331

FCV =

1.392

ccc=

1.4

Table 8. Summary and comparison of chronic values for bensulide.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

Pesticide

Most Sensitive OPP ALB
(Year published and species)

OW GLI Tier II value
(# of ACRs filled,
magnitude relative to ALB)

OW Modified HCos
(# of MDRs filled, # of genera
available, magnitude relative
to ALB)

Bensulide

11 (ig/L

(2016; Daphnia magna;
invertebrate)

0.88 ng/L

(GLI Tier II; 1 ACR filled,
12.5X)

1.4 (ig/L

(2 MDRs, 7 genera, 7.9X)

Figure 2 shows a chronic genus-level sensitivity distribution for the propazine dataset. Major
taxonomic groups are delineated by different symbols. Lines denoting the OPP chronic
benchmark values, GLI Tier II calculated chronic value, and modified HCos value are included.

261


-------
10,000

1,000

01
"O

"3

w
c
01
CO



~

Fish



A

Invertebrate



•

Nonvascular plant



¦

Vascular plant





-Modified HC05





GLI Tier II



— . .

Vascular Plant ALB





Invertebrate ALB

100

10

Anabaena

Skeletonema r RaPhidocelis

Skeletonema

V

Navicula (non-definitive, less than value)

Lemna (non-definitive, less than value)

1

1

A Daphnia (non-definitive, less than value)

Vascular Plant ALB = 42 |ig/L

Invertebrate ALB = 11 |ig/L

Modified HC05 = 1.4 |ig/L

1 	 	

GLI Tier II = 0.88 ng/L

0.0

0.1

0.2

0.3	0.4	0.5	0.6	0.7

Chronic Sensitivity Centile

0.8

0.9

1.0

Figure 2. Bensulide genus-level chronic SD.

Symbols represent Genus Mean Chronic Values (GMCVs) calculated using all available data from an Office of Water ECOTOX
search in 2021 and the Office of Pesticide Programs (OPP) registration review document for bensulide (U.S. EPA 2016).

262


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2.1.4.3 Bensulide References

MRID 44720402. Kransfelder, J.A. and L. Stuerman. 1998. Static Toxicity Test for Determining
the Effects of Test Substances to the Green Alga, Selenastrum capricornutum. Unpublished study
conducted by ABC Laboratories, Inc., Columbia, Missouri. ABC Study No. 44601. Study
sponsored by Gowan Company, Yuma, AZ. Study completed December 11, 1998.

MRID 44720403. Kranzfelder, J.A. and L. Stuerman. 1998. Static Toxicity Test for Determining
the Effects of Test Substances to the Blue-green Alga, Anabaena flos-aquae. Unpublished study
conducted by ABC Laboratories, Ins., Columbia, Missouri, ABC Study No 44602. Study
sponsored by Gowan Company, Yuma, AZ. Study completed December 11, 1998.

MRID 44720405. Kransfelder, J.A. and L. Stuerman. 1998. Static Toxicity Test for Determining
the Effects of Test Substances to the Saltwater Diatom, Skeletonema costatum. Unpublished
study conducted by ABC Laboratories, Inc., Columbia, Missouri. ABC Study No. 44604. Study
sponsored by Gowan Company, Yuma, AZ. Study completed December 11, 1998.

MRID 44720406. Kranzfelder, J.A. and L. Stuerman. 1998. Static Toxicity test for Determining
the Effects of the test Substance to Duckweed, Lemna gibba G3. Unpublished study conducted
by ABC Laboratories, Inc. Columbia, Missouri. ABC Study No. 44605. Study sponsored by
Gowan Company, Yuma, AZ. Study completed December 11, 1998.

MRID 44720407. Kranzfelder, J.A., L. Stuerman, and D. Malorin. 1998. Life-cycle toxicity test
of Daphnia magna under flow-through conditions. Unpublished study conducted by ABC
Laboratories, Inc., Columbia, Missouri. ABC Study No. 44606. Study sponsored by Gowan
Company, Yuma, AZ. Study completed December 14, 1998.

MRID 44720408. Kranzfelder, J.A., L. Stuerman, and D. Malorin. 1998. Early life-stage toxicity
test of Fathead Minnow, Pimephales promelas, under flow-through conditions. Unpublished
study conducted by ABC Laboratories, Inc., Columbia, Missouri. ABC Study No. 44607. Study
sponsored by Gowan Company, Yuma, AZ. Study completed December 10, 1998.

MRID 45063401. Kranzfelder, J.A., L. Stuerman, and D. Malorin. 1998. Life-cycle toxicity test
of Daphnia magna under flow-through conditions. Unpublished study conducted by ABC
Laboratories, Inc. Columbia, Missouri. ABC Study No. 44606. Study sponsored by Gowan
Company, Yuma, AZ. Study completed December 14, 1998.

MRID 45334101. Madsen, T.J. andM. Goble. 2001. Toxicity of Bensulide Technical to
Duckweed, Lemna gibba G3 Determined Under Static Test Conditions. Unpublished study
conducted by ABC Laboratories, Inc., Columbia, Missouri. ABC Study No. 46422. Study
sponsored by Gowan Company, Yuma, AZ. Study completed January 30, 2001.

MRID 49001601. Leak, T. 2012. Besulide: Life-cycle Toxicity test with the Fathead Minnow,
Pimephales promelas, Under Flow-through Conditions. Unpublished study conducted by ABC
Laboratories, Inc. Columbia, Missouri. Laboratory Report ID 67498. Study sponsored by Gowan
Company, Yuma, AZ. Study completed October 30, 2012.

MRID 49110401. Rebstock, M. 2013. Bensulide: Chronic Toxicity Test with the Cladoceran,
Daphnia magna, Exposed Under Static-Renewal Conditions. Unpublished study performed by
ABC Laboratories, Inc., Columbia, MO. Laboratory Study No. 69125. Study sponsored by
Gowan Company, Yuma, AZ. Study initiated September 25, 2012 and completed April 24, 2013.

263


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MRID 49378102. Leak, T. 2011. Bensulide: Life-cycle Toxicity Test with the Fathead Minnow
Pimephales promelas, Under Flow-through Conditions. Unpublished study conducted by ABC
Laboratories, Inc., Columbia, Missouri. Study ID No. 67498. Study sponsored by Gowan
Company, Yuma, AZ. Amended study completed May 7, 2014.

U.S. Environmental Protection Agency. Pesticide Ecotoxicity Database (Formerly:
Environmental Effects Database (EEDB)). Environmental Fate and Effects Division, U.S.EPA,
Washington, D.C., 1992. ECOREF #344

U.S. Environmental Protection Agency. 2024. Draft Comparison of Aquatic Life Protective
Values Developed for Pesticides under the Federal Insecticide, Fungicide, and Rodenticide Act
(FIFRA) and the Clean Water Act (CWA). EPA-820-D-24-002.

264


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2.1.5 Comparison of Aquatic Life Toxicity Values for Glyphosate: Data Sources and
Considerations

Data used in the Draft Comparison of Aquatic Life Protective Values Developedfor Pesticides
under the Federal Insecticide, Fungicide, andRodenticide Act (FIFRA) and the Clean Water Act
('CWA) (U.S. EPA 2024) were obtained from the Office of Pesticide Programs (OPP) registration
review document for gylphosate (U.S. EPA 2009).

2.1.5.1 Glyphosate Acute Toxicity Data

Acute data for glyphosate are shown in Table 1. Ranked invertebrate GMAVs from all data
sources are listed in Table 2.

Table 1. Acute toxicity data of glyphosate to freshwater aquatic organisms.

(MDR specifies OW minimum data requirements under t

ie Guidelines.)

OW
MDRa

Species

LC50

SMAV

GMAV

MRID
REF

Plant
Plant

Cyanobacterium (Anabaena
flos-aquae)

11720
15000

13259

13259

40236904
44320639

F

Midge (Chironomus
plumosus)

13000

13000

13000

162296

D

Water Flea (Daphnia magna)

134000

134000

134000

44320631

Plant
Plant
Plant

Duckweed (Lemna gibba)

11900
24000
25500

19384

19384

44320638
45773101
40236905

B

Bluegreen sunfish (Lepomis
macrochirus)

45000

45000

45000

44320630

Plant

Diatom (Navicula peliculosa)

39900
22400

29896

29896

40236902
44320641

A
A

Rainbow Trout

(Oncorhynchus mvkiss)

77,600
134000

101973

101973

44125705
44320629

B

Fathead Minnow (Pimephales
promelas)

67900

67900

67900

44125704

Plant

Plant
Plant

Green algae (Raphidocelis
subcapitata)

12100

12540
14000

12855

12855

4023690

40236901
44320637

a OW MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important
wannwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

265


-------
OPP Acute Benchmark Values

The OPP nonvascular plant benchmark value for glyphosate is 11,400 |ig/L, which is the LC50
for the Green algae (Raphidocelis subcapitata). The OPP vascular plant benchmark value is
11,900 |ig/L, which is the LC50 for L. gibba.

The OPP invertebrate acute benchmark value is 26,600 |ig/L, which is V2 the LC50 for C.
plumosis.

OPP fish acute benchmark value is 21,500 |ig/L, which is V2 the LC50 for L. macrochirus.
GLI Tier II Acute Value Calculation

The acceptable acute dataset for propazine fulfills four of the eight MDRs, corresponding to the
use of a Secondary Acute Factor (SAF) of 7. Applying the SAF to the lowest, most sensitive
GMAV regardless of taxa (i.e., 12,855 |ig/L for the Green algae (Raphidocelis subcapitata)), the
calculated Secondary Acute Value (SAV) is 3,213 |ig/L. The Secondary Maximum Criterion
(SMC), which is calculated as half the SAV, is 1,607 |ig/L.

Detailed calculations for the SMC are shown below:

Lowest GMAV

12,855

SAV = —-— = 3,213 |xg/L
SAV

SMC =	

2

3 213

SMC = = 1,607 |xg/L

Modified Acute HC05

The genus-level modified acute HC05 calculated following the U.S. EPA (1985) methodology for
the four most sensitive genera regardless of taxa (Table 2) in the glyphosate dataset was 9,816
|ig/L (Table 3).

Table 2. Glyphosate SMAVs and GMAVs (iig/L).

(ioniis

Species

S\1 AY

(IMAY

(;may

kiink

MIJR

(J roup

Daphina

magna

134,000

134,000

9

D

Oncorhynchus

mykiss

101,973

101,973

8

A

Pimephales

promelas

67,900

67,900

7

B

Lepomis

macrochirus

45,000

45,000

6

B

Navicula

peliculosa

29,896

29,896

5

Plant

Lemna

gibba

19,384

19,384

4

Plant

Anabaena

flos-aquae

13,259

13,259

3

Plant

Chironomus

plumosus

13,000

13,000

2

F

Raphidocelis

subcaptata

12,855

12,855

1

Plant

266


-------
a OW MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important
wannwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

Table 3. Modified acute HCos for glyphosate calculated following the U.S. EPA (1985)

N

Rank

GMAV

ln(GMAV)

ln(GMAV)2

P=R/(N+1)

sqrt(P)

9

4

19,384

9.872

97.46

0.4000

0.6325



3

13,259

9.492

90.11

0.3000

0.5477



2

13,000

9.473

89.73

0.2000

0.4472



1

12,855

9.461

89.52

0.1000

0.3162



Sum:



38.30

366.8

1.000

1.944







S2 =

2.13

L =

8.865

A =

9.192

FAV =

9,816

Table 4. Comparison of acute values for glyphosate.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

ratio >1 indicates the OPP value is hig

ier than the OW value.

Pesticide

OPP Most Sensitive ALB
(Year published, species)

OW GLI Tier II value
(# of MDRs filled, magnitude
relative to ALB)

OW Modified HCos/2

(# of MDRs filled,
# of genera available,
magnitude relative to ALB)

Glyphosate

11,900 (ig/L
(2016; Lemna gibba;
vascular plant)

1,607 ng/L

(GLI Tier II; 4 MDRs filled,
7.4X)

4,908 (ig/L

(4 MDRs, 9 genera, 2.4X)

Figure 1 shows a genus-level sensitivity distribution for the glyphosate dataset. Major taxonomic
groups are delineated by different symbols. Lines denoting the OPP acute benchmark values,
GLI Tier II calculated acute value, and modified HCos value are included.

267


-------
1,000,000

100,000

cuo
3

0)
+¦"

ro

en

o

Q.
_>

10,000

1,000

~

Fish

A

Insect

X

Invertebrate

•

Nonvascular plant

¦

Vascular plant



- Modified HC05/2

— *

• GLI Tier II



¦¦ Vascular Plant ALB

	

- Invertebrate ALB



r Raphidocelis
	A.	

0.0

0.1

0.2

X

Navicula

Lemna

j-Anabaena ¦	|nvertebrate alb = 12,100 ng/L

Invertebrate ALB = 12,100 |ig/L
Vascular Plant ALB = 11,900 |ig/L

Modified HC05/2 = 4,908 ng/L

GLI Tier II = 1,607 ng/L

r

0.3 0.4 0.5 0.6 0.7
Acute Sensitivity Centile

0.8

0.9

1.0

Figure 1. Glyphosate genus-level acute SD.

Symbols represent Genus Mean Acute Values (GMAVs) calculated using all available data from the Office of Pesticide Programs
(OPP) registration review document for glyphosate (U.S. EPA 2009).

268


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2.1.5.2 Glyphosate Chronic Toxicity Data
Data Sources and Considerations

Chronic toxicity data for glyphosate were obtained from OPP's registration review document for
glyphosate (U.S. EPA 2009). The final chronic glyphosate dataset consisted of NOECs/LOEC
for six species (Table 5).

Table 5. Chronic toxicity data of glyphosate to freshwater aquatic organisms. (MDR
specifies OW minimum data requirements under the Guidelines.) 	

MDR

Species

NOAEC

LOAEC

SMCV

GMCV

MRID

Plant
Plant

Cyanobacterium

(Anabaena fios-aquae)

12000



12000

12000

40236904
44320639

D
D

Waterflea

(Daphnia magna)

49900
240000

95700

69104

69104

124763

Plant

Plant
Plant

Duckweed

(Lemna gibba)

7560

14100

7560

7560

44320638

45773101
40236905

Plant
Plant

Diatom

(Navicula peliculosa)

18000



18000

18000

40236902
44320641

B

Fathead Minnow

(Pimephales promelas)

>25700



> 25700

> 25700

108171

Plant

Plant
Plant

Green algae

(Raphidocelis subcapitata)

10000



10000

10000

4023690

40236901
44320637

a OW MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important

wannwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	a planktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	a benthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

H.	a family in any order of insect or any phylum not already represented.

OPP Chronic Benchmark Values

The OPP vascular plant benchmark value for glyphosate is 1,300 |ig/L. There is no OPP
nonvascular benchmark plant value for glyphosate.

The OPP invertebrate chronic benchmark value is 49,900 |ig/L, which is the NOEC for Daphnia
magna.

269


-------
The OPP fish chronic benchmark value is 25,700 |ig/L, which is the NOEC for Pimephales
promelas.

GLI Tier II Chronic Value Calculation

Paired quantitative acute and chronic toxicity data were available for Pimephales promelas and
D. magna / C. plumosus allowing for the calculation of two ACRs. Per the GLI Tier II
methodology, the default value of 18 was used to fulfill the remaining one ACR. The resulting
Pimephales promelas and D. magna / C. plumosus ACR are 3.77 and 1.94, respectively, and the
final SACR is 5.09. Dividing the SAV of 1,607 |ig/L by the SACR of 5.09 results in a Secondary
Continuous Value of 315.6 |ig/L, and a Secondary Continuous Concentration of 316 |ig/L.

Detailed calculations for the SCV are shown below:

SACR = Geometric Mean of the ACRs

SACR = V3.77# 1.94# 18 = 5.09

SCV =

SACR

1,607

5CK = W = 316 V9/1

Modified Chronic HCos

The genus-level modified chronic HC05 calculated following the U.S. EPA (1985) methodology
for the four most sensitive genera regardless of taxa (Table 6) in the glyphosate dataset was
5,087 |ig/L (Table 7).

Table 6. Glyphosate SMCVs and GMCVs (^ig/L).

(Ion us

Species

SMC V

(;m( y

(IMC V
kiink

MDR

(iroup

Daphnia

magna

69,104

69,104

6

D

Pimephales

promelas

>25,700

>25,700

5

B

Navicula

peliculosa

18,000

18,000

4

Plant

Anabaena

flos-aquae

12,000

12,000

3

Plant

Raphidocelis

subcapitata

10,000

10,000

2

Plant

Lemna

gibba

7,560

7,560

1

Plant

a OW MDR Groups - Freshwater:

A.	the family Salmonidae in the class Osteichthyes

B.	a second family in the class Osteichthyes, preferably a commercially or recreationally important
warmwater species (e.g., bluegill, channel catfish, etc.)

C.	a third family in the phylum Chordata (may be in the class Osteichthyes or may be an amphibian, etc.)

D.	aplanktonic crustacean (e.g., cladoceran, copepod, etc.)

E.	abenthic crustacean (e.g., ostracod, isopod, amphipod, crayfish, etc.)

F.	an insect (e.g., mayfly, dragonfly, damselfly, stonefly, caddisfly, mosquito, midge, etc.)

G.	a family in a phylum other than Arthropoda or Chordata (e.g., Rotifera, Annelida, Mollusca, etc.)

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H. a family in any order of insect or any phylum not already represented.

Table 7. Modified chronic HCos for glyphosate calculated following the U.S. EPA (1985)
methodology.

N

Rank

GMCV

ln(GMCV)

ln(GMCV)2

P=R/(N+1)

sqrt(P)

6

4

18,000

9.798

96.00

0.5714

0.7559



3

12,000

9.393

88.22

0.4286

0.6547



2

10,000

9.210

84.83

0.2857

0.5345



1

7,560

8.931

79.76

0.1429

0.3780



Sum:



37.33

348.8

1.429

2.323







S2 =

5.00

L =

8.035

A =

8.534

FCV =

5,087

Table 8. Summary and comparison of chronic values for glyphosate.

Magnitude relative to ALB is the OPP ALB/OW value, the ratio for the OPP value/OW value for
each value comparison. A ratio <1 indicates the OPP value is lower than the OW value and a

Pesticide

Most Sensitive
OPP ALB
(Year published and
species)

OW GLI Tier II value
(# of ACRs filled, magnitude
relative to ALB)

OW Modified HCos
(# of MDRs filled, # of genera
available, magnitude relative
to ALB)

Glyphosate

1,300 pg/L
(Lemna gibbet;
vascular plant)

316 pg/L

(GLI Tier II; 2 ACRs filled,
4.IX)

5,087 pg/L

(2, MDRs, 6 genera, 0.26X)

Figure 2 shows a chronic genus-level sensitivity distribution for the glyphosate dataset. Major
taxonomic groups are delineated by different symbols. Lines denoting the OPP chronic
benchmark values, GLI Tier II calculated chronic value, and modified HCos value are included.

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100,000

-I

~

Fish



A

Invertebrate

j

•

Nonvascular plant

1

¦

Vascular plant

1



- Modified HC05

j

—, .

GLI Tier II

1

........

* Lowest NOAEC, Vascular Plant

- Anabaena

10,000

m

m

re

w

o

Q. 1,000
>
w

¦ Lemna

Raphidocefis

^- Navicula

r Lowest NOAEC, Vascular Plant = 7,560 pg/L

Modified HC05 = 5,087 pg/L

/I

GLI Tier II = 316 pg/L

100

0.0

0.1

0.2	0.3	0.4	0.5	0.6	0.7

Chronic Sensitivity Centile

0.8

0.9

1.0

Figure 2. Glyphosate genus-level chronic SD.

Symbols represent Genus Mean Chronic Values (GMCVs) calculated using all available data from the Office of Pesticide Programs
(OPP) registration review document for glyphosate (U.S. EPA 2009).

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2.1.5.3 Glyphosate References

MRID 108171. Chronic toxicity of glyphosate to the Fathead Minnow (Pimephales promelas
Rafinesque). Unpublished study conducted by EF& G Bionomics Aquatic Toxicology
Laboratory, Wareham, MA. Study sponsored by Monsanto Company, St Louis, Missouri. 0178-
041-06/097759-5-8.

MRID 124763. McKee, R.J., W.A McAllister, andM. Schofield. 1982. Chronic Toxicity of
Glyphosate (AB-82-036) to Daphnia magna Under Flow-through Test Conditions. Unpublished
study conducted by Analytical Bio-Chemistry Laboratories, Columbia, Missouri. Report No.
AB-82-036.Study sponsored by Monsanto Chemical Company, St. Louis, Missouri. Study
completed September 9, 1982.

MRID 162296. Folmar, L.C., H. O. Sanders and A.M. Julin. 1979. Toxicity of the herbicide
glyphosate and several of its formulations to fish and aquatic invertebrates. Arch. Environn.
Contam. Toxicol 8: 269-278.

MRID 4023690. Incomplete MRID (see MRID 40236901).

MRID 40236901. Hughes, J.S. 1987. Volume I: The Toxicity of Glyphosate Technical to
Selenastrum capricornutum. Unpublished study conducted by Maclolm Pirnie, Inc., White
Plains, NY. Laboratory Project ID 1092-02-1100-1. Study sponsored by Monsanto Agricultural
Company, Chesterfield, Missouri. Study completed April 27, 1987.

MRID 40236902. Hughes, J.S. 1987. Volumen II: The Toxicity of Glyphosate Technical to
Navicula pelliculosa. Unpublished study conducted by Maclolm Pirnie, Inc., White Plains, NY.
Laboratory Project ID 1092-02-1100-2. Study sponsored by Monsanto Agricultural Company,
Chesterfield, Missouri. Study completed April 20, 1987.

MRID 40236904. Hughes, J.S. 1987. Volume IV: The toxicity of Glyphosate Technical to
Anabaena flos-aquae. Unpublished study conducted by Malcolm Pirnie, Inc. White Plains, NY.
Laboratory Project ID 1092-02-1100-4. Study sponsored by Monsanto Agricultural Company,
Chesterfield, Missouri. Study completed April 20, 1987.

MRID 40236905. Hughes, J.S. 1987. Volume V: The Toxicity of Glyphosate Technical to
Lemna gibba. Unpublished study conducted by Maclolm Pirnie, Inc., White Plains, NY.
Laboratory Project ID 1092-02-1100-5. Study sponsored by Monsanto Agricultural Company,
Chesterfield, Missouri. Study completed April 13, 1987.

MRID 44125704. Ward, T.J., J.P. Magazu and R.L. Boeri. 1996. Acute toxicity of Glygran
WDG to the Fathead Minnow. Pimephales promelas. Unpublished study conducted T.R. Wilbury
Laboratories, Inc, Marblehead, MA. Study No. 1008-LP. Sponsored by Lewis and Harrison,
Washington, DC. Study complected August 2, 1996.

MRID 44125705. Boeri, R.L., J.P. Magazu, and T.J. Ward. 1996. Acute Toxicity of Glygran
WDG to the Rainbow Trout, Oncorhynchus mykiss. Unpublished study conducted by T.R.
Wilbury Laboratories, Inc, Marblehead, MA. Study No. 1056-LH. Sponsored by Lewis and
Harrison, Washington, DC. Study complected August 2, 1996.

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MRID 44320629. Kent, S.J., D.S. Morris, J.E. Caunter and S.K. Comish. 1995. Glyphosate
Acid: Acute Toxicity to Rainbow Trout (Oncorhynchus mykiss). Unpublished study conducted
by Brixham Environmental Laboratory, ZENACA Limited, Devon, UK. Laboratory ID
BL5552/B. Study sponsored by ZENECA Ag Products, Wilmington, DE. Study completed on
September 15, 1995.

MRID 44320630. Kent, S.J., J.E. Caunter, D.S. Morris, and P.A. Johnson. 1995. Glyphosate
Acid, Acute Toxicity to Bluegill Sunfish (Lepomis macrochirus). Unpublished study conducted
by Brixham Environmental Laboratory, ZENACA Limited, Devon, UK. Laboratory ID
BL5553/B. Study sponsored by ZENECA Ag Products, Wilmington, DE. Study completed on
November 24, 1995.

MRID 44320631. Morris, D.S., S.J. Kent, A.J. Banner, and S.J. Wallace. 1995. Glyphosate Acid:
Acute Toxicity to Daphnia magna. Unpublished study conducted by Brixham Environmental
Laboratory, Zenaca Limited, Devon, UK Laboratory Project ID BL5551/B. Study sponsored by
ZENACA Ag Products, Wilmington, DE. Study completed July 26, 1995.

MRID 44320637. Smyth, D.V., S.J. Kent, D.S. Morris, D.J. Morgan, and S.E. Magor. 1995.
Unpublished study conducted by Brixham Environmental Laboratory, ZENACA Limited,

Devon, UK. Laboratory ID BL5550/B. Study sponsored by ZENECA Ag Products, Wilmington,
DE. Study completed on August 12, 1995.

MRID 44320638. Smyth, D.V., S.J. Kent, D.S. Morris, S.K. Comish, andN. Shillabeer. 1996.
Glyphosate Acid: Acute Toxicity to Duckweed (Lemna gibba). Unpublished study conducted by
Brixham Environmental Laboratory, Zenaca Limited, Devon, UK Laboratory Project ID
BL5662/B. Study sponsored by ZENACA Ag Products, Wilmington, DE. Study completed
January 31, 1996.

MRID 44320639. Smyth, D.V., N. Shillabeer, D.S. Morris, and S.J. Wallace. 1996. Glyphosate
Acid: Toxicity to Blue-green alga (Anabaena flos-aquae). Unpublished study conducted by
Brixham Environmental Laboratory, Zenaca Limited, Devon, UK. Laboratory Project ID
BL5698/B. Study sponsored by ZENACA Ag Products, Wilmington, DE. Study completed
March 9, 1996.

MRID 44320641. Smyth, D.V., S.J. Kent, D.S. Morris, P.A. Johnson, andN. Shillabeer. 1996.
Glyphosate Acid: Toxicity to the Freshwater Diatom (Navicula pelliculosa). Unpublished study
conducted by Brixham Environmental Laboratory, ZENACA Limited, Devon, UK. Laboratory
ID BL5673/B. Study sponsored by ZENECA Ag Products, Wilmington, DE. Study completed on
February 3, 1996.

MRID 45773101. Boeri, R.L. and T.J. Ward. 2002. Glyphosate Acid: Toxicity to the Duckweed,
Lemna sp. Unpublished study conducted by T.R. Wilbury Laboratories, Inc, Marblehead, MA.
Study Number 2066-LH. Study sponsored by Industria Prodotti Chimici, S.p.A, Milanese, Italy.
Study completed July 9, 2002.

Saka, M., N. Tada, and Y. Kamata. Chronic Toxicity of 1,3,5-Triazine Herbicides in the
Postembryonic Development of the Western Clawed Frog Silurana tropicalis. Ecotoxicol.
Environ. Saf. 147:373-381, 2018. ECOREF #178499

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U.S. Environmental Protection Agency. Pesticide Ecotoxicity Database (Formerly:
Environmental Effects Database (EEDB)). Environmental Fate and Effects Division, U.S.EPA,
Washington, D.C., 1992. ECOREF #344.

U.S. Environmental Protection Agency. 2024. Draft Comparison of Aquatic Life Protective
Values Developed for Pesticides under the Federal Insecticide, Fungicide, and Rodenticide Act
(FIFRA) and the Clean Water Act (CWA). EPA-820-D-24-002.

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