Harmonization of Guidelines between
Office of Prevention, Pesticides and Toxic Substances and
Organization for Economic Cooperation and Development
Science Oversight Group
September 30,1993
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Harmonization of Guidelines between
Office of Prevention, Pesticides and Toxic Substances and
Organization for Economic Cooperation and Development
Table of Contents
I. Introduction 1
n. Issue I: Species
A. Regulatory utility 1
1. Species data 3
2. Case studies: Clusters and "safer chemicals" 8
B. Harmonization 10
C. Options 10
IE. Issue II: Age of Test Birds 14
References 16
Table of Figures
Figure 1: Frequency Distribution of the Interspecies Range of Insecticide
LCsos in the Mayer Database 4
Figure 2: Interspecies Comparison Ranked by Rainbow Trout 5
Figure 3: Interspecies Comparison Ranked by Bluegill Sunfish 6
Figure 4: Interspecies Comparison Ranked by Bobwhite Quail 7
Figure 5: Corn Cluster - Fish Acute Quotients 9
Figure 6: Turf Cluster -- Bird Acute LDso per square foot 11
Figure 7: Comparison of International Recommendations for Test Species 12
Appendices
Appendix 1: Species Variability 1-1
Appendix 2: Case Studies 2-1
Appendix 3: International Requirements for Test Species 3-1
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Harmonization of Guidelines between
Office of Prevention, Pesticides and Toxic Substances and
Organization for Economic Cooperation and Development
I. Introduction
International harmonization of ecotoxicity test guidelines may reduce the burden of
repeated testing from chemical companies attempting to satisfy similar data requirements.
Further, if the various nations review comparable data in a comparable way, reviews can be
shared. Shared data and data reviews save resources for participating nations and eliminate
redundant waiting periods for chemical companies.
All data submission guidelines can be harmonized, where regulatory questions are
similar. Within this assumption, OPPTS has given staff members two goals: harmonization and
continued support of regulatory needs. OPP and OPPT have resolved most harmonization issues
except test species and the age of test birds. These two issues also can be harmonized, but will
require additional steps.
Harmonization has been undertaken to increase regulatory efficiency and multi-lateral
communication, while reducing non-tariff trade barriers. Specifically, with toxic chemicals and
pesticides, four advantages of harmonization have emerged:
decreased market-entry, financial and time burden on industry;
improved international efficiency of information exchange;
common review of comparable data; and
increased confidence that common conclusions are reached.
To meet regulatory needs, all submitted data must answer scientific questions applied to
informed risk management decisions. The four primary risk management needs for toxic
chemicals and pesticides are:
identification of hazard and risk;
comparative assessments of alternative pesticides;
evaluation of risk reduction for mitigation options; and
scientific defense of regulatory decisions.
The purpose of this meeting is twofold. The first is to respond to the July 15,1993
Firestone memo that followed the July 14,1993 meeting of the Science Oversight Group (SOG).
The second is to raise for consideration the remaining issue in Organization for Economic
Cooperation and Development (OECD) guidelines harmonization: the age of birds in avion
dietary studies.
II. Issue I: Test Species
A. Regulatory utility
OPP and OPPT have resolved most of the harmonization issues except test species.
Differences in test species selection is a generic issue between OPPTS and OECD guidelines.
OPPTS testing guidelines currently designate a limited number of species. For pesticide
registration, LCso tests are required for rainbow trout (cold-water species) and bluegill sunfish
(warm-water species). Similarly, avian LCso tests are required for the mallard duck and
bobwhite quail. In contrast, OECD guidelines allow selection from among a broader group of
I
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test animals which includes non-native and less sensitive species. (Figure 7 compares OPP and
OECD species for four tests: avian dietary, avian reproduction, fish acute toxicity and freshwater
invertebrate.)
When OPP presented the species issue to the SOG on July 14, some questions were
raised. Principally, SOG members asked OPP to demonstrate whether species variation is
actually great enough to affect regulatory decisions. Specifically, the Firestone memo of July 15,
1993 asked OPP to:
analyze the distribution of species differences;
use case studies to demonstrate how alternative species would affect regulatory
decisions;
identify international testing policies; and
assess OECD reaction to changes in choosing test species for ecotoxicity testing.
Species selection
Species selection is important in the guideline harmonization effort because it critically
affects OPP's ecological risk assessment and risk management processes. Test species selection
has a substantial impact on identification of risk, comparison of chemicals and defense of risk
assessment and risk management decisions of the pesticide program. OPPT guidelines and data
needs are less affected, as test species selection is a less critical issue in their regulatory program.
Ecological risk identification
Ecological risk identification is partially based on the relative sensitivity of the species
tested. If insensitive test species are used, pesticide risk may be underestimated. This problem
can be partially solved by an assessment factor such as that utilized in OPPT assessments. In the
pesticide program, where a large proportion of the substances pose significant risk to non-target
species, this concern is somewhat less central to the programs operation than chemical
comparison, which allows us to set priorities among many risk targets.
Defending decisions
The use of native game species in ecotoxicology is a long-standing practice that aids in
defending decisions. Historically, risk management decisions have been based on risk to native
species that are likely to be exposed and are of concern to the public. The importance of this
native species factor depends heavily on the audience, however. It may mean very little to those
who are accustomed to dealing only with human health risk assessments, where interspecies
extrapolation is almost always required. Professional ecolpgists and wildlife and fisheries
biologists in North America favor the continued use of native species to address the concerns of
those who hunt, fish or engage in other outdoor activities.
Comparative ecological risk assessments are an important aspect of the pesticide
program. Alternative comparisons for the same pesticide use are prepared for:
all special reviews where ecorisk triggers are included,
RED reviews where ecorisk levels of concern have been exceeded,
new pesticide or new use reviews where ecorisk levels of concern have been
exceeded, and
new pesticide reviews under the safer pesticide policy.
The above OPP activities are very important because numerous pesticides pose high risks
to non-target species. Given the agricultural need for pesticides, it will be a long time before we
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can eliminate pesticide risks to ecosystems. We can reduce them, however, and comparisons of
different pesticide alternatives are central to pesticide risk reduction.
For the foreseeable future, comparative risk assessments for pesticide alternatives will be
made with laboratory data, rather than incident reports. Incident reports can confirm risk, but
rarely allow direct comparisons of one pesticide to another. This is particularly true since
comparison of potential use rather than current use is most needed. For example, Diazinon has a
long list of bird kills. But the mere absence of bird incidents for its alternatives does not indicate
that they will be safer if used in place of Diazinon. The alternatives may lack incident reports
because they are not used much (or at all, if the alternative chemical is new) or because they are
used where fewer birds are exposed or where incidents are unlikely to be detected and reported.
Because chemical comparisons are the most crucial OPP task affected by the species
issue, specific case studies (Section II-A.2, page 8) demonstrate how the species tested may
affect OPP decisions.
1. Species data
Species variation in the susceptibility of organisms to pesticides is well documented
(Department of Health, Education and Welfare, 1969; Macek and McAllister, 1970; Hill etal.,
1975; Kenaga, 1978,1979; Tucker and Leitzke, 1979; Doherty, 1983; LeBlanc, 1984; Suter and
Vaughan, 1985; Thurston et al., 1985; Mayer and Ellersieck, 1986; Mayer et al., 1987;
Joermann, 1991; Hill, 1992; Suter, 1985). LeBlanc (1984) reported that taxonomic relationships
have a much greater influence on comparative sensitivities to pesticides than to other chemicals.
He reasoned that pesticides kill target organisms by specific modes of action, and responses vary
more among all taxa than among related species.
Evaluation of interspecies sensitivity differences must compare data from a large number
of chemicals and species tested under identical or substantially similar conditions. For fish, data
compiled in Mayer and Ellersieck (1986) include results from 4,902 tests performed with 66
species and 410 chemicals. (See Figure 1 for fish species tested on insecticides.) For the graphs
presented here, the data were narrowed to obtain the four most frequently tested fish species
(rainbow trout, bluegill sunfish, channel catfish and fathead minnow). The data were further
selected to include only those tests conducted with technical-grade materials, similar
environmental conditions, and generally conformed to ASTM standard methods. Although this
analysis covers many North American test species, it fails to include some OECD species (carp,
Japanese medaka, zebrafish and guppy). Data were not available to evaluate the variation that
might be introduced by the use of these species. Given these specified conditions, 42 chemicals
were compared.
For birds, the data set is limited to chemicals for which test data are available on the avian
test species of interest. The avian data used in the OPP sensitivity analyses were LCso values on
50 pesticides from Hill et al. (1975), LDso values for six avian species with 16 pesticides from
Tucker and Haegele (1971), and bobwhite quail and mallard duck LDso values for 18 pesticides
from Hudson et al. (1984). For data from Hudson et al., an attempt was made to match toxicity
values on birds of the same age, same sex, and same chemical purity. When more than one
toxicity value was available or the toxicity value was a range, the mean value was used in the
comparison.
Figures 2,3 and 4 compare species response across the test compounds (X axis) against
the log of the LCso (Y axis). The chemicals are ranked by decreasing toxicity for a given species
(the lower the LCso, m^ greater the toxicity). The chemicals are identified by numbers in the key
on appendix page 1-7.
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Frequency Distribution of the
Interspecies Range of Insecticide LCSOs (max/min)
for Fish in the Mayer Database
30
CO
20
10
c
f*
1-5
5-10
10-100 100-1,000
maximum LC50/minimum LC50
1,000-10,000 >10,000
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10UO(X>
IUOGO-
lOXt
-Q
a.
O
ID
O
10Q
Interspecies Comparisons
Ranked By Rainbow Trout
~iiii iiiiirniiiiiiiiiiiiiiiiiiiiiiiiiiiiir
17 13 16 23 10 1 4 22 12 40 3 6 10 24 2O 42 9 33 27 11 7 21 5 36 30 26 34 36 18 30 14 31 26 41 16 8 29 37 32 36 28 2
Chemicals
Rainbow trout » Bluegill sunfish -*- Fathead minnow -e- Channel catfish
HPI
a
C
-------
1000OO
1000O
lOttk
CL
a.
o
in
O
1Ot
Interspecies Comparisons
Ranked By Bluegill Sunfish
\ i i i i i ] iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiir
17 16 40 13 19 1 12 23 22 4 10 33 27 3 0 42 6 24 20 36 26 21 7 II 34 18 16 31 37 5 26 38 14 30 30 29 2 41 36 32 B 28
Chemicals
Bluegill sunfish + Rainbow trout *- Fathead minnow -e- Channel catfish
T|
*'
c.
-------
10000q
E
a
^CL
o
m
CD
0
1000
Interspecies Comparisons
Ranked by Bobwhite Quail
Chemicals
Bobwhite Quail Mallard
Pheasant
Japanese quail
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The figures show that there is a/ijeuigh correlation/among a wide range of toxicities; that
there are large differences in sensitivityxb^tweenjpficies; and that some species tend to be more
sensitive to pesticides than others.
2. Case Studies: Clusters and "Safer Chemicals"
The cluster approach to reviewing existing pesticides focuses on a specific crop use
pattern. Chemicals having the same use pattern are reviewed simultaneously. Using the cluster
approach, OPP can compare risks if one or more pesticides are canceled or restricted, since the
probable alternatives are evaluated at the same time.
OPP intends to promote the registration of safer pesticides. One way to achieve this goal
is by easing the registration process for pesticides that appear to be safer than those currently
registered. Often, pesticides proposed as safer by their manufacturers have fairly high toxicity to
non-target species other than mammals. However, they still may pose substantially less risk man
the chemicals currently on the market. Hazard and risk comparisons evaluate the degree to
which these pesticides are "safer."
Case Study I: Corn Insecticide Cluster
The first cluster analysis was conducted for all 14 corn insecticides used at the time of
planting (see appendix page 2-1). The purpose of this phase of the analysis was to select the
most problematic alternatives for in-depth review. By definition, the pesticides selected for in-
depth review will be those posing the greatest risk to human health and the environment. The
program can then be assured that any restrictions on their use will result in reduced risk, since the
remaining alternatives will be generally safer.
In the pilot analysis, the four compounds selected, based on ecological and health risk,
were Terbufos, Phorate, Chlorpyrifos and Fonofos. EFED staff feels very comfortable with these
four because:
they were selected based on tests in species that are at risk and of concern:
the choice agrees with the judgment of experienced OPP biologists; and
the choice is consistent with what we know about adverse field effects.
As shown in the first ranking (Figure 5), the bluegill sunfish risk quotients for these four
chemicals rank at the top and substantially higher in acute risk to freshwater fish than the
remaining alternatives. The bluegill sunfish was chosen for use in this analysis because the
largest number of com cluster chemicals included LCso values for this species.
We simulated the effect of using OECD species on our regulatory process with three
random trials. In each trial, one species was randomly selected from among those with
appropriate LCso values for each pesticide (appendix page 2-4). The risk quotient determined by
the LCso for that species was calculated for each of the three trials. The resultant ranking is
shown to the right of the original bluegill sunfish ranking in Figure 5. We would not necessarily
expect a single risk index to select the four compounds as well as the bluegill sunfish ranking
did. A useful index would, however, show these four pesticides above the concern level and
among the five to six highest-risk compounds. The actual results for random species are very
different. In fact, random species use sometimes ranks the most problematic pesticides below
what our judgement and experience tell us.
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Risk
Quotient
10
I
a
s
I
0.1
a
c
I
0.01
Corn Cluster - Fish Acute Quotients
(Est. Environmental Concentration/LCSO):
[TBF|
CPF|
FNF PHO
TFL
CTP
ETH PMT
ESF
MTH
PHB
CBL
MP
CaoLClustebflueaiUjrrial
Bluegill & Three Random Trials TFI
cr
ET
PM
ES
\jn
Ml
PH
|FNF| FNF 1 PHO | M"P
TFL
TFL FNF TFL
ITBFI
CTP CTP CTP
ETH PHO ETH
PMT ESF
PMT CPF| PMT
ETH |CPF
ESF ESF
TBF
IPHO
CBL
MTH
PHB CBL PHB CBL |TBF| PHB
MTH MTH
MP MP MP
Random TriaJ-L Random-Trial-H Random. Trial TIT
TBF=Turbufos
CPF=Chlorpyrifos
FNF=F6nofos
PHO=Phorate
TFL=Tefluthrin
CTP=Chk>rcthoxyphos
ETHoEihoprop
PMT=Permethrin
ESPaEsfenvaleme
MTH=Methomyl
PHB=Phostebupirin
CBL=Carbaiyl
MP=Meihyl Parathion
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Case Study II: Turf Insecticide Cluster and NTN
The turf insecticide cluster was used in the second case study. The pilot study selected
several turf insecticides for in-depth review based on all the areas of risk.
Diazinon clearly emerged as the chemical of greatest concern for birds among the turf
cluster insecticides. The available information on field effects and the judgement of OPP
biologists support this concern.
In comparison, NTN is a new chemical claimed to be safer for turf. Although this claim
seemed to be supported for mammals and some other non-target species, NTN appears to be very
persistent. As such, a chronic risk concern was identified for aquatic and bird species. Also,
there appears to be an acute risk to marine invertebrates and small birds. Only the acute avian
risk had sufficient cross-species data, so although it is not the endpoint of greatest concern, it is
used in this case study. Only those turf cluster pesticides considered alternatives to NTN were
used in this analysis (appendix page 2-5).
The analysis was conducted like that for the com cluster case study. The first ranking
shows results for a single species (bobwhite quail; see Figure 6). This puts Diazinon at the top
and NTN far below. Of the three randomized species rankings, all place NTN at the bottom, but
not necessarily with a clear distance between it and the others. Two of the three place Diazinon
at the top. However, in one case (randomized trial I), Diazinon and NTN are fairly close
together. Faced with this result, we would be reluctant to categorize NTN as safer, and would
wonder whether a large number of incidents would occur if NTN replaced Diazinon.
Based on these analyses, we therefore conclude that species variability is sufficient to
affect OPP regulatory decisions.
B. Harmonization
A survey of other countries, regulatory authorities and multi-national industry (appendix
page 3-1) shows that the ecotoxicological test species in actual use internationally are generally
very close to those used in the U.S. Figure 7 lists the test species used by OPP and those of the
EC and compares them with species recommended by OECD.
Other authorities typically use safety factors with ecotoxicological hazard data. The size
of the safety factor is generally adjusted to take into account the number of species for which test
data re available and any differences in sensitivity between the species tested and those
ecologically or commercially important native species potentially at risk. Thus, when high
potential risk is indicated, other countries are likely to require an additional round of tests in
native species. The OPP approach, in contrast, gives direct results.
C. Options to Resolve Issue 1: Test Species
Option 1. Develop correction factors based on round-robin testing, as well as
existing data, to compare species.
Testing would be performed to insure results on all OECD recommended species for
chemicals representing many structural classes.
10
-------
LD50
squan
100
10
1
»
0.1
per
ifoot
TR
IF
B,IZ
CH
(NTN)
Turf Cluster Bobwhite Trial
Turf Cluster - Bird Acute LD50 per square foot:
Bobwhite & Three Random Trials
DZ DZ
CH IF B
B TR B TR
IZ TR
IF DZ CH IF
IZ IZ
(NTN) (NTN)
(NTN)
Random Trial I Random Trial II Random Trial III
DZ=Diazinon
TR=Trichlorfon
IF=lsofenphos
B=Bendiocaib
CH=Chlorpyrifos
IZ=kazophos
3!
Lo
c
-------
Comparison of International Recommendations
for Test Species
Test Guidelines
OPP
EC (for pesticides)
OECD
Avian dietary test
Bobwhite quail
Mallard duck
Bobwhite quail
Japanese quail
Mallard duck
Bobwhite quail
Japanese quail
Mallard duck
Common pigeon
Ring-necked pheasant
Red-legged partridge
Avian reproduction test
Bobwhite quail
Mallard duck
Japanese quail
Mallard duck
Bobwhite quail
Japanese quail
Mallard duck
Fish acute toxicity test
Bluegill sunfish
Rainbow trout
Bluegill sunfish
Rainbow trout
Bluegill sunfish
Rainbow trout
Zebrafish
Fathead minnow
Common carp
Guppy
Japanese medaka
Freshwater invertebrate test
Daphnia magna
Daphnia magna
Daphnia magna and
other species; OECD
expert panel
recommends Daphnia
magna
TT
Lo"
c
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Pros:
Enables U.S. to accept data on OECD species.
Correction factors derived from testing will be based upon studies
specifically designed for this purpose.
Risk assessment is less likely to be driven by test species selection.
Cons:
Correction factors introduce additional uncertainty in comparative risk
assessments.
Correction factors are likely to be controversial.
Requires more testing and analyses of data.
Will take several years.
May not accurately account for variabilities among important species (may
underestimate or overestimate comparative risks).
Option 2. Use tests in OECD species for screening purposes.
OPPTS would accept test results with OECD species with correction factors or
assessment factors, such as those currently used by OPPT. If a level of concern is reached,
testing would be required with benchmark standard species to allow appropriate comparative
analyses.
Pros:
Stronger basis for defending regulatory decisions than Option 1.
Flexible and politically appealing.
Consistent with certain international approaches (New Zealand, Canada).
Allows for partial comparison of pesticide alternatives.
Cons:
Decisions likely to take longer, to require more data and to require more
OPP resources.
Database may lose its historical utility.
Would require some changes in risk assessment and management process.
May result in more testing of different species than other options.
Option 3. Continue to require U.S. benchmark species and seek to change the
OECD guidelines.
With this option, the United States would work through the OECD to require native
benchmark species which have databases. Additional species could vary from country to
country.
Pros:
Achieves international harmony if OECD guidelines change.
U.S. ability to perform and defend risk assessments for North American
ecology will be sustained.
Reduces uncertainty in comparative risk assessment.
Requires relatively few resources.
13
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Cons:
Potential repercussions within OECD.
Implementation requires negotiations within OECD.
Recommendation:
OPPTS prefers option 3 (restrict species to U.S. species and seek to change the OECD
guidelines). This option is consistent with the current trend in the European Community (EC),
which is narrowing its range of species for pesticides and moving toward acceptance of U.S.
species. With this option, OPP scientists will be able to make more reliable comparisons of
incoming data, and they will not have to change their existing risk assessment policies and
approaches, which have taken many years to formulate. Decisions based upon indigenous
species will also be easier to defend than those based upon foreign species.
Although this option does not provide additional data on species differences, it
encourages a faster resolution of the issue than other options will provide. With option 3, the
U.S. will need to develop its position on the test species issue and take it to the OECD for
resolution. As discussed in Appendix 3, the U.S. position is close to that of the EC, and has a
good chance for being accepted, at least for pesticides. It is also an appropriate time to take this
issue to the OECD because they are currently considering change for the pesticide guidelines.
ffl. Issue 2: Age of Test Birds
Avian dietary studies expose birds to a treated diet for five days. The age of the test birds
greatly affects the reliability of the resultant toxicity endpoints. If birds are too young, they will
rely on unabsorbed yolk to survive. If birds are too old, they will survive the five-day interval
without feeding. Differences in biology between species are therefore critical to the optimal age
for testing. Mallard ducks should be tested from five to seven days old at test initiation, and
bobwhite quail should be from 10 to 14 days old. The OECD and OPPT guidelines recommend
birds be tested from 10 to 17 days old at initiation.
Test animals must be susceptible to the conditions of the test so their response can be
quantified with reasonable statistical certainty. This can be met only for species that can be
maintained in captivity in good-health and cannot survive for five days without eating (Hill,
1992). Mallard ducks more than 10 days old can survive the five-day test without eating and
therefore are not susceptible to the test.
The importance of seemingly trivial difference in age on LCsos has been well
documented. For example, between seven and 14 days, LCsos increased an average of 1.5-fold
for three organophosphates and two carbamates tested with Japanese quail from a single hatch.
This was demonstrated for 10-day-old ducklings. LCsos increased by 1.5- to 3.8-fold between
five and 10 days of age for all but fensulfothion (Hill, 1992).
Recommendation:
OPP believes that the age of test birds is especially crucial in the avian dietary study. In
1982, the program established age limits of 10 to 14 days for bobwhite quail and five to 10 days
for mallard ducks. These age limits are based on available evidence in Hudson, et al. (1972) and
on comments received by the FIFRA Science Advisory Panel in its 1980 review of OPP's
Subdivision E Test Guidelines. These ages also are consistent with the 1980 scientific consensus
of the American Society of Testing Materials on the avian dietary test.
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We recommend taking this issue to OECD, as part of the workshop on avion testing, and
recommend changing the age of test birds to 10 to 14 days for bobwhite quail and five to 10 days
for mallard ducks.
15
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References
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Mayer, F. L., Jr., C. H. Deans, and A. G. Smith. 1987. Inter-taxa correlations for toxicity to
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17
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Appendix 1:
Species Variability
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Frequency Distribution of the Interspecies Range of Insecticide
(Max/Mini for Fiah in the Mayer Database
1-5
Allethrin
AMDRO
Chlordane HCS
Chlordireform
Coumaphos
Dicrotophoe
Diflubenzuron
Oinethoate
Dimtramine
EndosuHan
EPN
Ethylan
Fonofosi
Fospirate
Heptachlor Ep.
Lethane
5-10
Akton
Chlorphyrifoe-M
DOE
Dichlofenthion
Dioxathion
DNOC
Fenthion
Fenvalerate
Heptachlor
Lindane
Mevinphoa
Ortho 11776
Oxyde melon -M
Propoxur
Ronnel
Ryania
10-100
Acephate
Aldicarb
Aldrin
Azinphoa-E
Benzene HCL
Carbofuran
Chlordecone
Chlorfenvinphoe
Crotoxyphoa
DDT
Diazinon
Dichlorvoe
Dieldrin
Dilan
Dimethrin
Dtoutfuton
100-1.000
Aminocarb
Carbaryl
Carbofenthion
Chlordane
Chlorpyrifoa
DDD
Methomyl
Parathlon
Parathion-Dlq.
Phorate
Phosnet
RU-11679
Temephoa
Trlchtorfon
1.000-10.000
Azinphoa-M
Leptophoa
Terfoufoa
More than 10.000
Malathion
-------
1-5
Methidathion
Mathil Trithion
Oxamyl
Oxythioqulnot
Pernethrin
Phoaaloa
Profarofo*
Terpan Poly C
Tatrachlonrin
Thianata
Trichloronata
5 10
SD-7438
SO- 17250
10-100
Ob-Tram Allathrin
Endrin
Ethion
Fenitrothion
Jodphanphoa
Landrin
Mathoprana
Mathoxychlor
Mathyl Parathion
Maxacarbata
Monocrotophoa
Nated
Phoaphamldon
Phoxim
Pyrathrin
Raamethrin
Rotanona
S-Bioallathrin
SO- 16898
TEPP
Toxaphana
100-1.000
1.000-10.000
Mora than 10.000
-------
Frequency Distribution of the Interspecies Range
of LCM» (Max/Kin) for a Subset of Four Fish from the Mayer Database
1-4X
Aminocarb
Captan
Chlordane HCS
DDT
Dieldrin
Dinitramin
Endosulfan
Fenitrothion
Glyphosate
Heptachlor
Lindane
Methoxychlor
Mexacarbate
Parathion methyl
Pthalic acid esters*
Purifloc C-31*
Pydraul 50E
5-lOx
Benzene
Carbaryl
Endrin
Folpet
MON-0818*
Met homy 1
Parathion ethyl
PCP
Toxaphene
Trichlorphon
10-lOOx
Aldrin
Benomyl
Chlordane
Ethion
Houghto-safe*
Malathion
Naled
Phosmet
Phosphamidon
Phoxim
Trifluralin
100-1, OOOx
Antimycin A
Azinphos methyl
Crotoxyphos
* Non-pesticides
-------
OECD Species vs. Comparison Graphs
Freshwater Fish
Family
Salmonidae
Cyprinidae
Ictaluridae
Centrarchidae
Oryziidae
Family
Anatinae
Phasianidae
Columbidae
Placeidae
Species
Rainbow trout
Fathead minnow
Zebrafish
Carp
Channel catfish
Bluegill sunfish
Japanese medaka
Birds
Species
Mallard duck
Bobwhite quail
Japanese quail
Chukar
Ring-necked pheasant
Red-legged partridge
Common pigeon
House sparrow
Species
Reported in
OECD QPP Graphs
^ +
V +
V
V
+
V +
V
Species Reported
in OPP Graphs:
OECD LC50 LD50
V + +
V +
V + +
V + +
V
V +
+
l-H
-------
10000Q
10000
O
10
O
I
Ul
1000:
100;
INTERSPACES COMPARISONS
Comparison v. Fathead minnow
0.1-
Trout
* Sunflsh
Mlnnow
Catfish
16 17 19 13 I 12 40 & 10 i 2*7 i 24 ^1 42 &
4 20 38 18 39 J7 ^) 14 & Jl ^6 J6 30 IS 34 41 & ^5 32 11 i ^8 35
Chemicals
-------
100000:
10000
ID
Q.
0.
O
in
O
1000=
INTERSPACES COMPARISONS
Comparison v. Channel catfish
0.1
17 16 19 ^3 9 40 12 22 T 23 24 10 27 1 33 jr & 20 21 26 38 30 41 36 14 42 l'l 3*1 3*7 39 4 i 15 32 18 25 2 34 28 29 i 35
Chemicals
-------
Key; Incerspecies Comparisons of LC50s
Q|H)jCBj fUiabov uwl BltwfiU tunHah Faibcad nioaov '
1 AMria
. 2 Afflinoearb
3 Afliinycin A
4 Azirphoi methyl
5 BenoojH
6 Bcrueoc hcacMoride
7 ClpUA
8 C*rbiry»
9 Oilordane
10 CWordjne HCS-3260
!I C-otoryphoi
'.2 DDT
13 Dieldria
14 Di&Jiramine
15 Duul/cuoo
16 Endo»utfifl
17 Eadhn
18 Eihion
19 FenitrothJon
20 rolpet
21 ClypboHU
22 Hepuehlor
23 Hou(hto-*4/eH20
24 UxiiM
25 Maljthiofl
26 Me:boayf
77 MethatychJor
28 Meuearbicc
29 MON-08I8
30 Nalcd
31 Piraition ethyl
Ti ParaJuoo methyl
33 Pei'jciJoropitaoJ
34 Photaet
35 Pboiphaaidoa
36 Phcxia
37 P:M(uIie »ad aten
33 PurifbeC-31
39 PydnuJSOE
40 Taapbea*
41 TnchJorpboo
42 TriOunlia
16
13JOO
12
4J
170
18
712
19JO
42
24.9
7Z4
8.7
U
830
1850
1.4
0.75
500
2.4
39
130
7.4
1.7
27
200
1600
62
12000
2000
195
1430
3700
52
300
7800
ISO
2600
446
700
104
1730
41
6J
3100
38
22
850
67
141
6760
57
29J
152
8.6
3.1
1520
300
U
0.61
210
34
72
135
13
12
68
103
1050
32
22900
3000
2200
400
4380
32
200
3400
82
700
1470
2200
14
3170
«
8-2
8500
40
235
roo
1Z5
200
14600
113
244
11900
122
34
1440
4300
U
14
720
22
296
97
23
35
87
8650
2800
39
17000
1400
3300
2350
8900
205
7300
100000
2900
1300
490
1300
18
7900
105
53
10000
4230
730
7)
105
77.5
15800
6.7
454
1500
21.5
4.3
1370
4700
1.5
032
7600
O
108
130
25
43
44
8970
530
52
11400
13000
710
2650
5240
68
10600
70000
i::o
2900
680
3000
13.1
-580
2200
1-7
-------
Q.
O
to
O
INTERSPECIES COMPARISONS
COMPARISON V. COTURNIX
Chemicals
Bobwhito * Mallard
Pheasant -«- Coturnix
-------
CL
O
10
O
INTERSPECIES COMPARISONS
COMPARISON V. PHEASANT
Chemicals
Bobwhite
Mallard
Pheasant
Coturnix
-------
^ ^^
Q.
O
in
O
\
o
INTERSPECIES COMPARISONS
COMPARISON V. MALLARD
Chemicals
Bobwhite * Mallard -*- Pheasant
Coturnix
-------
CD
O)
o
in
O
INTERSPECIES COMPARISONS
COMPARISON V. MALLARD
Chemicals
Mallard
Coturnix
* Pheasant
x- Pigeon
Chukar
Sparrow
-------
INTERSPECIES COMPARISONS
COMPARISON V. PHEASANT
Chemicals
Mallard
Coturnix
Pheasant -* Ghukar
Pigeon -*- Sparrow
-------
0>
CD
O
in
O
INTERSPECIES COMPARISONS
COMPARISON V. COTURNIX
Chemicals
Mallard
Coturnix
Pheasant -*~ Chukar
Pigeon -^t- Sparrow
-------
INTERSPECIES COMPARISONS
COMPARISON V. PIGEON
^
CD
£
CD
O
in
O
Chemicals
-ft MM It Jl '^fcll " fct*/-J M>-
Maiiaru
1 1 ^^J »4l !-» 1VA _. j
-1 ooiurnix J
D !» /»*» f *» t"**1 v»
r neasani ^
^ r igeon *
*-* Chukar
fc- Sparrow
-------
^
o>
£
o>
o
in
O
\
Cn
INTERSPECIES COMPARISONS
COMPARISON V. CHUKAR
Chemicals
Mallard * Pheasant -**- Chukar
Coturnix -* Pigeon -air- Sparrow
-------
O
in
O
INTERSPECIES COMPARISONS
COMPARISON V. SPARROW
Chemicals
Mallard + Pheasant -*- Chukar
Coturnix -* Pigeon -sAc- Sparrow
-------
Most Sensitive Species for Fish and Avian Toxicity Data
Fish Toxicity Data
Comparison of 42 LCso values for four fish species (Mayer and Ellersieck, 1986) yielded
the following frequencies for most sensitive species:
Rainbow trout 48%
Bluegill sunfish 33%
Channel catfish 14%
Fathead minnow 5%
The OECD species include common carp, zebrafish, Japanese medaka and guppy. These
species are more closely related taxonomically to the fathead minnow than to the other three
species.
Avian Toxicity Data
Comparison of 49 LCso values for four avian species (Hill et al., 1975) yielded the
following frequencies for most sensitive species:
Bobwhite quail 59%
Japanese quail 22%
Pheasant 12%
Mallard duck 6%
Comparison of 16 LDso values for six avian species (Tucker and Haegele, 1979) yielded
the following frequencies for most sensitive species:
Mallard duck 44%
Pigeon and sparrow 19%
Pheasant 12%
Chukar 6%
Japanese quail 0%
Comparison of 17 LDso values for bobwhite quail and mallard ducks (Hudson et al.,
1984) yielded the following frequencies for most sensitive species:
Bobwhite quail 65%
Mallard duck 35%
l-n
-------
Appendix 2:
Case Studies
-------
Corn Cluster Chemicals:
Freshwater Fish 96-hr LC50s (ppb)
Chemical
TERBUFOS
CHLORPYRIFOS
FONOFOS
PRORATE
TEFLUTHRIN
CHLORETOXYPHOS
ETHOPROP
Species
Rainbow Trout
Fathead Minnow
Channel Catfish
Bluegill sunfish
Cutthroat Trout
Rainbow Trout
Lake Trout
Channel Catfish
Bluegill sunfish
Rainbow Trout
Bluegill sunfish
Cutthroat Trout
Rainbow Trout
Northern Pike
Channel Catfish
Bluegill sunfish
Largemouth Bass
Walleye
Rainbow Trout
Bluegill sunfish
Bluegill sunfish
Rainbow Trout
Bluegill sunfish
No. Tests
10
2
1
10
4
4
6
1
5
1
1
2
2
1
1
6
1
2
1
1
Range
8-15
150-390
1.1-2.4
5-26
1-51
73-244
1.7-4.2
44-66
13-21
1.0-4.0
57-340
Median
10
270
1800
2
16
11
170
280
2
20
7
55
17
110
280
2
5
200
0.06
0.13
2.30
1150
300
-------
Corn Cluster Chemicals:
Freshwater Fish 96-hr LC50s (ppb) cont'd.
Chemical
PERMETHRIN
ESFENVALERATE
METHOMYL
V
I
V
PHOSTEBUPIRIM
CARBARYL
Species
Rainbow Trout
Brook Trout
Fathead Minnow
Channel Catfish
Bluegill sunfish
Rainbow Trout
Bluegill sunfish
Cutthroat Trout
Rainbow Trout
Atlantic Salmon
Brook Trout
Fathead Minnow
Channel Catfish
Bluegill sunfish
Largemouth Bass
Bluegill sunfish
Coho Salmon
Chinook Salmon
Cutthroat Trout
Rainbow Trout
Brown Tout
Brook Trout
Lake Trout
Goldfish
Carp
Fathead Minnow
Black Bullhead
No. Tests
9
3
2
1
10
1
1
1
21
9
3
3
5
20
2
1
5
1
10
18
2
9
5
2
1
3
1
Range
2.9-8.2
2.3-5.2
5.7-5.7
4.5-13.0
860-3200
560-1400
1220-2200
1500-2800
300-1800
870-2800
760-1250
1150-4340
970-7100
320-3500
2000-6300
680-4560
690-2300
12800-13200
7700-14600
Median
5.20
3.20
5.70
7.20
7.00
1.20
0.30
6800
1400
1050
1500
1800
530
690
1005
89
2400
2400
4500
1205
4150
1700
870
13000
5280
14000
20000
-------
Corn Cluster Chemicals:
Freshwater Fish 96-hr LC5os (ppb) cont'd.
Chemical
CARBARYL (cont'd.)
METHYL PARATHION
Species
Channel Catfish
Green Sunfish
Bluegill sunfish
Largemouth Bass
Black Crappie
Yellow Perch
Coho Salmon
Cutthroat Trout
Rainbow Trout
Brown Trout
Lake Trout
Goldfish
Carp
Fathead Minnow
Black Bullhead
Channel Catfish
Green Sunfish
Bluegill sunfish
Largemouth Bass
Yellow Perch
No. Tests
3
2
13
1
1
14
1
2
2
1
2
1
1
3
1
1
2
3
1
1
Range
7790-17300
9460-11200
1800-3900
350-13900
1850-4800
2750-3700
3360-3780
7200-9960
6860-6900
1000-6900
Median
15800
10550
6200
6400
2600
3800
5300
3365
3225
4700
3570
9000
7130
8900
6640
5240
6880
4380
5200
3060
TRIMETHECARB
Rainbow Trout
1
1000
-------
Corn Cluster Chemicals:
Trials of Three Random Species
V
\
Chemical
TERBUFOS
CHLORPYRIFOS
FONOFOS
PRORATE
TEFLUTHRIN
CHLORETHOXYPHOS
ETHOPROP
PERMETHRIN
ESFENVALERATE
METHOMYL
PHOSTEBUPIRIM
CARBARYL
METHYL PARATHION
TRIMETHECARB
Random Trial I
Rainbow Trout
Channel Catfish
Rainbow Trout
Walleye
Bluegill sunfish
Bluegill sunfish
Rainbow Trout
Bluegill sunfish
Rainbow Trout
Rainbow Trout
Bluegill sunfish
Coho Salmon
Yellow Perch
Rainbow Trout
Random Trial II
Fathead Minnow
Lake Trout
Bluegill sunfish
Channel Catfish
Bluegill sunfish
Bluegill sunfish
Bluegill sunfish
Rainbow Trout
Rainbow Trout
Fathead Minnow
Bluegill sunfish
Yellow Perch
Lake Trout
Rainbow Trout
Random Trial III
Channel Catfish
Rainbow Trout
Bluegill sunfish
Bluegill sunfish
Rainbow Trout
Bluegill sunfish
Bluegill sunfish
Fathead Minnow
Bluegill sunfish
Bluegill sunfish
Bluegill sunfish
Yellow Perch
Largemouth Bass
Rainbow Trout
-------
Turf Cluster: Avian LD^ Data For NTM Alternatives
CHEMICAL
EEC=mg/ft2
ORIGINAL RQ*
SPECIES LD^s
Canada goose
Mallard duck (M)
Bobwhite quail (BW)
California quail
Japanese quail
Ring-necked pheasant (Ph)
Chukar (Ch)
Sandhill crane
Common pigeon
Common crow
Starling (St.)
Red-winged blackbird (RW)
Common grackle (CG)
House sparrow (HS)
RANDOM RQs* 1
II
III
DIAZINON
50
BW56
2.5
10.0
4.2
4.3
3.2
85.0
3.2
7.5
7.5
St. 6. 6
CG 75
HS75
TRICHLORFON
83
BW42
37
22
40
43
M 25
RW 22
St. 24
ISONFENPHOS
21
BW27
32
8.7
5.3
M 7.3
RW 44
M 7.3
BENDIOCARB
43
BW 25
3.1
19
6.9
BW 26
BW 26
RW 71
ISAZOPHOS
20
BW20
61
11
BW20
M 3.7
M 3.7
CHLORPYRIFOS
47
BW 16
60
32
68
16
13
61
38
18
32
43
13
10
15
Ph 40
Ch 8.6
M 5.6
NTN
5.2
BW0.4
152
41
HS 1.4
HS 1.4
BW0.4
Risk Quotients are calculated for the weight of a Bobwhite quail
-------
Appendix 3:
International Requirements
for Test Species
-------
International Requirements for Test Species
In response to a request from the SOG, OPP surveyed a number of pesticide regulatory
authorities, as well as a key industry representative, about international requirements for
ecotoxicological test species. OPP contacted the European Community (EC), Canada and New
Zealand. OPP also contacted the chairman of NACA's International Committee, who represents
the association in obtaining multi-national registrations.
Based on this survey, it appears that the majority of OECD member nations, including the
EC, are generally using the same set of test species that are in use in the United States. Thus, it is
likely that if we were to go to the OECD and request that test species be considered, that we
could be effective in achieving a significant narrowing of recommendations.
Summary
A survey of other countries' regulatory authorities and multinational industry shows that
the ecotoxicological test species in actual use internationally are generally very close to those
used in the United States. The attached chart lists the test species used by OPP an those of the
EC and compares them with species recommended by OECD.
Other authorities typically use safety factors with ecotoxicological hazard data. The size
of the safety factor is generally adjusted to take into account the number of species for which test
data are available and any differences in sensitivity between the species tested and those
ecologically or commercially important native species potentially at risk. Thus, when high
potential risk is indicated, other countries are likely to require an additional round of tests in
native species. The OPP approach, in contrast, gives us results directly.
European Community
The EC scientific experts felt it was essential to recommend a concise set of test species
as standards for its 12-member national in order to ensure mutual acceptance of test data
developed for registration. With one minor exception, the interchangeable use of Japanese quail
or bobwhite quail as representative upland game birds, the EC species are identical to United
States species. In choosing their standard species, the EC considered three factors:
existence of a relevant data base;
availability of guidelines validated for that species; and
ecological or commercial importance, if possible.
Dr. Mark Lynch of the EC feels that in light of these criteria, the species listed in Figure 7
are the best choice for use by the 12 EC member nations.
Industry
Multinational companies in the United States are comfortable in testing pesticides in
United States test species. They find that databases using these species are generally acceptable
internationally.
New Zealand and Canada
In polling New Zealand and Canada, OPP had selected representatives of two countries
outside of the EC, with relatively minor pesticide markets. In each case, pesticide authorities
take a flexible approach to test species. The U.S. test species, with the exception of the bluegill
3-1
-------
sunfish, are also native to Canada. When pesticides for use in either country pose high potential
risks, particular non-target native species will be tested. In addition, each country relies on field
testing or monitoring for high risk pesticides.
EC Choice of Test Species
Dr. Lynch, who has written the guidance for testing and risk assessment of pesticides in
the EC, has noted that the driving force for selection by the EC of a limited set of test species for
development of data for pesticides is the desirability of ensuring production of reliable data,
while satisfying Article 10 of Directive 91/414/EC Concerning the Placing of Plant Protection
Products on the Market. Article 10 specifies that a member state, in handling an application for a
product already authorized by another member state must:
... refrain from requiring the repetition of tests and analyses already carried out in
connection with the authorization of the product in that member state, . . . also
authorize the placing of that product on the market in its territory, to the extent
that agricultural, plant health and environmental (including climatic) conditions
relevant to the use of the product are comparable in the regions concerned.
In developing testing guidance for the EC, the scientific experts felt that if mutual
recognition of testing and registrations was to work effectively and at the same time minimize
testing on vertebrate species, they would have to specify a limited set of test species.
In choosing standard test species for use by registrants applying for registrations in EC
member nations, three criteria were used:
existence of a relevant data base;
availability of guidelines validated for that species; and
ecological or commercial importance, if possible.
The test species recommended by the EC are shown in Figure 7. They are very similar to
those used in the United States for registration of pesticides. The EC recommends the mallard
duck and either the Japanese quail or bobwhite quail. All three species have large data bases. Of
the fish recommended, bluegill sunfish is not ecologically relevant, but there is a large body of
test data for it. The rainbow trout is commercially important in Europe and known to be
sensitive. The EC also specifies Daphnia magna, which recently has been recommended by an
OECD expert panel.
Test Species -- U.S. Industry Point of View
Dr. Richard Nielsen chairs NACA's International Committee and participates in OECD
meetings as the industry representative to the U.S. delegation. He also has experience at
American Cyanamid Co. in multinational registration of pesticides. His company must pick test
species that will satisfy the rest of the world, as well as EPA. He feels this can be done readily;
in his experience, tests on U.S. species are acceptable worldwide. The only exception to this is
for product applications to Japan, which also requires testing on the carp. For those few
registrations in Japan, his company performs an extra LCso test on the carp.
Test Species -- Canadian Registrations
Canadian guidelines do not explicitly specify test species. According to Dr. Pierre
Mineau, Canadian authorities generally receive test data performed on U.S. species and may also
receive studies performed on a wider range of test species as well. For pesticide chemicals that
-------
have high potential toxicity, Canada prefers testing in a wide variety of species. When tests are
performed only in two avian or aquatic species, safety factors are used. The more species tested,
the narrower the safety factor.
Canadian authorities will accept avian testing of the bobwhite quail and mallard duck,
both native game species. They also accept test data, when available, from Japanese quail.
However, they pointed out that smaller birds, and possibly passerines, are more sensitive to many
pesticides.
Canadian authorities require aquatic testing of the rainbow trout and a second species.
They accept studies of bluegill sunfish. Rainbow trout is a native species and is more sensitive to
pesticides. For pesticides with high exposure or high potential risk, testing will also be required
on salmon, which are native to Canada and ecologically and commercially important.
Test Species ~ New Zealand
Dr. Adrian Foley in New Zealand said that companies generally register pesticides in that
country after they are registered elsewhere. As a result, the data New Zealand uses for
ecotoxicological risk assessment are generated for other authorities. They must extrapolate from
whatever species are tested, but they prefer to see several species tested.
They generally see data in mallard ducks and bobwhite quail, and are likely to see tests
performed on rainbow trout. If a chemical poses a special risk, as was the case for certain
aquatic herbicides, they will also require testing in native species for registration. New Zealand
pesticide authorities may require monitoring of pesticides in use, such as vertebrate poisons. In
those cases, they will receive information on effects in native species.
3-3
------- |