Amy L. Leaberry
United States
Environmental Protection
Agency
Off ice of Water
Regulations and Standards
Criteria and Standards Division
Washington DC 20460
                  Water
                  Ambient
                  Water  Quality
                  Criteria
                  for
                                                  EPA 440/5-86-005
                                                  September 1986
                  Chlorpyrifos  -  1986

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AMBIENT AQUATIC LIFE WATER QUALITY CRITERIA FOR

                  CHLORPYRIFOS
      U.S. ENVIRONMENTAL PROTECTION AGENCY
       OFFICE OF RESEARCH AND DEVELOPMENT
       ENVIRONMENTAL RESEARCH LABORATORIES
               DULUTH, MINNESOTA
           NARRAGANSETT, RHODE ISLAND

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                                 NOTICES
This document has been reviewed by the Criteria and Standards Division,
Office of Water Regulations and Standards, U.S. Environmental Protection
Agency, and approved for publication.

Mention of trade names or commercial products does not constitute
endorsement or recommendation for use.

This document is available to the public through the National Technical
Information Service (NTIS), 5285 Port Royal Road, Springfield, VA 22161.

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                                 FOREWORD
     Section 304(a)(l) of the Clean Water Act of 1977 (P.L. 95-217)
requires the Administrator of the Environmental Protection Agency to
publish water quality criteria that accurately reflect the latest scientific
knowledge on the kind and extent of all identifiable effects on health
and welfare that might be expected from the presence of pollutants in any
body of water, including ground water.  This document is a revision of
proposed criteria based upon consideration of comments received from
other Federal agencies, State agencies, special interest groups, and
individual scientists.  Criteria contained in this document replace any
previously published EPA aquatic life criteria for the same pollutant(s).

     The term "water quality criteria" is used in two sections of the
Clean Water Act, section 304(a)(l) and section 303(c)(2).  The term has a
different program impact in each section.  In section 304, the term
represents a non-regulatory, scientific assessment of ecological effects.
Criteria presented in this document are such scientific assessments.  If
water quality criteria associated with specific stream uses are adopted
by a State as water quality standards under section 303, they become
enforceable maximum acceptable pollutant concentrations in ambient waters
within that State.  Water quality criteria adopted in State water quality
standards could have the same numerical values as criteria developed
under section 304.  However, in many situations States might want to
adjust water quality criteria developed under section 304 to reflect
local environmental conditions and human exposure patterns before incorporation
into water quality standards.  It is not until their adoption as part of
State water quality standards that criteria become regulatory.

     Guidelines to assist States in the modification of criteria presented
in this document, in the development of water quality standards, and in
other water-related programs of this Agency, have been developed by EPA.
                                    William A. Whittington
                                    Director
                                    Office of Water Regulations and Standards

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                             ACKNOWLEDGMENTS
Loren J. Larson
(freshwater author)
University of Wisconsin-Superior
Superior, Wisconsin
                           Jeffrey L. Hyland
                           Robert E. Hillman
                           (saltwater authors)
                           BattelLe New England Laboratory
                           Duxbury, Massachussetts
Charles E. Stephan
(document coordinator)
Environmental Research Laboratory
Duluth, Minnesota
                           David J. Hansen
                           (saltwater coordinator)
                           Environmental Research Laboratory
                           Narragansett, Rhode Island
Clerical Support:
Shelley A. Heintz
Nancy J. Jordan
Terry L. Highland
Diane L. Spehar

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                                 CONTENTS






Foreword	    Lii




Acknowledgments	     iv




Tables	     vi






Introduction 	      1




Acute Toxicity to Aquatic Animals  	      4




Chronic Toxicity to Aquatic Animals  	      6




Toxicity to Aquatic Plants 	      7




Bioaccuraulation  	      8




Other Data	      9




Unused Data	     13




Summary	     15




National Criteria  	     17






References	     41

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                                  TABLES
                                                                        Page

1.  Acute Toxicity of ChLorpyrifos to Aquatic Animals  	    18

2.  Chronic Toxicity of Chlorpyrifos To Aquatic Animals  	    24

3.  Ranked Genus Mean Acute Values with Species Mean Acute-Chronic

    Ratios	27

4.  Toxicity of Chlorpyrifos to Aquatic Plants  	  30

5.  Bioaccumulation of Chlorpyrifos by Aquatic Organisms  	  31

6.  Other Data on Effects of Chlorpyrifos on Aquatic Organisms  ....  33
                                    VI

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Introduction*

     Chlorpyrifos** is one of several organophosphorus compounds developed

in the 1960s to replace persistent organochlorine pesticides.  It is

the active ingredient in various products designed to control a variety

of pests including fire ants, turf and ornamental plant insects, mosquitos,

cockroaches, termites, lice, and hornfli.es.  In the agricultural industry

in the United States, chlorpyrifos is used primarily to control pests on

cotton, peanuts, and sorghum.  In the past it was directly applied to

aquatic environments in mosquito, midge, and blackfly abatement projects,

but the current label states that it is not to be applied directly to

bodies of water.  Gray (1965) and Marshall and Roberts (1978) have reviewed

its composition and physical and chemical properties.

     Chlorpyrifos is available for pesticide applications as etnulsifiable

concentrates, wettable powders, dusts, granules, and controlled-release

polymers.  The resulting concentrations of chlorpyrifos in water and its

persistence varies from one form to another.  When applied to water,

emulsifiable concentrates and wettable powders generally produce a large

increase in chlorpyrifos concentrations immediately after application.

The concentration in water rapidly declines as chlorpyrifos is sorbe'd

onto sediments and suspended organics.  Granules and controlled-release

forms do not produce as rapid an increase Ln the concentration in water,

but the resulting concentration has a longer duration.
* An understanding of the "Guidelines for Deriving Numerical National Water
  Quality Criteria for the Protection of Aquatic Organisms and Their Uses"
  (Stephan et al. 1985), hereafter referred to as the Guidelines, and the
  response to public comment (U.S. EPA 1985a) is necessary in order to
  understand the following text, tables, and calculations.

**Dursban® and Locsban® are trade names owned by the Dow Chemical Company,
  Midland, MI for chlorpyrifos.

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     The percentage of active ingredient in available formulations varies




considerably, both between formulations and within a single formulation




over time as manufacturers' specifications change.  Such variations presumably




result in large changes in the amount, and possibly the identity, of the




unspecified ingredients.  These ingredients are considered inert, although




technical-grade chlorpyrifos has generally been found to be more toxic




than an equal quantity of active ingredient in a formulation (Darwazeh and




Mulla 1974; Jarvinen and Tanner 1982; Siefert et al. 1984).  For this




reason, the effects of the inert ingredients can not be discounted.




Furthermore, under normal application conditions, the commercial formulations




are often combined with petroleum products, such as No. 2 diesel oil and




kerosene, to increase the rate of dispersal.  Such solvents have been shown to




have significant toxic effects in addition to those associated with




chlorpyrifos (Jaranback and Frempong-Boadu 1966; Wallace et al. 1973).




     The toxicity of chlorpyrifos is probably the result of metabolic




conversion to its oxygen analogue, chlorpyrifos-oxon, and  its subsequent




inhibition of various enzymes (e.g., cholinesterases, carboxylases,




acetylcholinesterases, and mitochondrial oxidative phosphorylases).




Interference with acetylcholinesterase (AChE) is generally accepted to be




the major mode of action of organophosphorus pesticides.   Inhibition of AChE




results in accumulation of the neurotransmitter, acetylcholine,  in synapes




and disruption of normal neural transmission.  Although even substantial




reductions in brain AChE activity have not always been fatal to  fish, tne




effect of this condition on such functions as feeding and  reproduction in




nature is not known.




     Chlorpyrifos enters both freshwater and saltwater ecosystems primarily




as drift from spraying, and on particles eroded from treated areas.  Because




                                    2

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of  its affinity for organic soils, Little leaching occurs.  When unbound




chiorpyrifos enters an aquatic system, it appears to be rapidly sorbed to




suspended organics and sediment, although some is removed by volatilization




and degradation.  Its penetration into sediment appears to be shallow,




with most occurring in the upper several millimeters.  Menzie (1969)




reported that chiorpyrifos remained stable for long periods of time under




the acidic conditions (pH = 5 to 6) found in some salt marshes.




     Use of slow-release polymers in water probably results in differential




exposure, both in concentration and duration, between benthic and pelagic




organisms.  Organisms inhabiting the water-sediment interface probably




receive larger and more sustained concentrations than free-swimming




organisms.  Evans (1977) found concentrations of chiorpyrifos that were




still toxic to mosquito Larvae one year after application of a slow-release




polymer formulation to a natural pond.




     Because chiorpyrifos is rapidly metabolized by fish, with 3,5,6-




trichloro-2-pyridinol being the major product (Marshall and Roberts




1978), concentrations in wild fishes (Clark et al. 1984; Mulla et al.




1973) and cultured or experimental fishes (Macek et al. 1972; Siefert et




al. 1984; Winterlin et al. 1968-} are generally low.  Braun and Frank




(1980), Hughes (1977), Hughes et al. (1980), Hurlbert et al. (1970),




Macalady and Wolfe (1985), Nelson and Evans (1973), Rawn et al. (1978),




Siefert et al. (1984), and Winterlin et al. (1968) have reported




concentrations of chiorpyrifos in natural sediment and water samples.




     Unless otherwise noted, all concentrations reported herein are




expressed as chiorpyrifos, not as the material tested.  Whenever




adequately justified, a national criterion may be replaced by a




site-specific criterion (U.S. EPA 1983a), which may include not only




                                    3

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sice-specific criterion concentrations (U.S. EPA 1983b), but also site-




specific durations of averaging periods and site-specific frequencies of




allowed excursions (U.S. EPA 1985b).  The Latest comprehensive literature




search for information for this document was conducted in July, 1986;




some more recent information might have been included.






Acute Toxicity to Aquatic Animals




     Data, which are usable according to the Guidelines, on the acute




toxicity of chlorpyrifos to freshwater animals are available for seven




fish species and eleven invertebrate species (Table 1).  Invertebrates




are among the most sensitive and most resistant species, and the nine




most sensitive species are arthropods.  Although data are available for




eighteen species, no data are available for a planktonic crustacean, and




the snail, Aplexa hypnorum, is the only one of the eighteen that is not




an arthropod or a fish.  Within arthropods and fishes seoarately, and




within all species combined, there appears to be an inverse relationship




between size and sensitivity to chlorpyrifos.




     Species Mean Acute Values (Table 1) were calculated as geometric means




of the available acute values, and then Genus Mean Acute values V.Table 3)




were calculated as geometric means of the available freshwater Species




Mean Acute Values.  The most sensitive genus, Gammarus, is more than




4,300 times more sensitive than the most resistant genera, Aplexa, Carassius,




and Ictalurus, but the four most sensitive genera are within a factor of




4, and all are invertebrates.  Acute values are available for more than




one species in each of two genera, and the range of Species Mean Acute




Values within each genus is less than a factor of 3.  The freshwater




Final Acute Value for chlorpyrifos was calculated to be 0.1669

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using Che procedure described in Che Guidelines and che Genus Mean Acute




Values in Table 3.  Thus che freshwaCer Final Acute Value is higher than




the Species Mean Acute Value for one of three araphipods in the genus Gammarus.




     TesCs of Che acuCe toxicity of chlorpyrifos to saltwater animals have




been conducted with five species of invertebrates and ten species of




fish (Table 1).  The range of acute values extends from 0.01 ^ig/L for




adulc Korean shrimp., Palaemon macrodactylus, (EarnesC 1970) Co 1,991 Mg/L




for larvae of Che eascern oysCer, Crassostrea virginica, (BorChwick and




Walsh 1981).  Four species of saltwater arthropods have been Cesced




and they were all more sensitive Chan Che most sensitive fish species.




The range of acute toxicity values for fish is narrower than for invertebrates,




with LCSOs extending from 0.4 (Jg/L for 14-day-old larvae of che tidewater




silverside, Menidia peninsulae,  (Borthwick et al. 1985) Co 520 "jg/L for




juveniles of the gulf toadfish,  Opsanus beta, (Hansen et al. 1986).




     Borthwick et al.  (1985) conducted a series of 96-hr acuCe cescs




under boch sCacic and flow-through condicions wich four different ages




of larvae of three estuarine fishes (Table 1).  LC50s ranged from 0.4 to




5.5 ,jg/L for all tests.   In stacic tests, 14-day-old larvae were more




sensitive than newly hatched or 28-day larvae of all species.  Ln flow-




through tests, relative sensitivities of the ages were similar to those




in stacic tests for tidewater silverside, decreased wich age for Atlantic




silverside, and differed liccle for California grunion (Table 1).




     Of the twelve genera for which saltwater Genus Mean AcuCe Values are




available, che raosC sensitive genus, Mysidopsis,  is about 57,000 times




more sensitive than the most resistant genus, Crassostrea (Table 3).




Acute values are available for more than one species in each of two




genera, and the range of Species Mean Acute Values within each genus is




                                    5

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less than a factor of 5.7.  The saltwater Final Acule Value was calculated




to be 0.02284 ^ig/L, which is lower than the lowest Genus Mean Acute




Value.






Chronic Toxicity to Aquatic Animals




     Usable data on the chronic toxicity of chlorpyrifos are available




for only one freshwater species, the fathead minnow.  Chronic values for




technical-grade and encapsulated material were 2.26 ',Jg/L and 3.25 ,Jg/L>




respectively, in early life-stage tests (Jarvinen and Tanner 1982).




Growth over the 32-day test was the most sensitive parameter with




technical-grade chlorpyrifos, whereas with the encapsulated formulation,




growth and survival were equally sensitive.  In a life-cycle test with




the same species (Jarvinen et al. 1983), unacceptable effects occurred at




0.41 ,Jg/L in the first generation and at 0.12 >Jg/L in the second generation,




showing rather poor agreement between the early life-stage tests and the




life-cycle test.  Based on these results, the acute-chronic ratio for




chlorpyrifos is greater than 1,417 with the fathead minnow.  Jarvinen et




al. (1983) also estimated the chronic effect of chlorpyrifos on the




viable biomass recruitment of a natural population of the fathead minnow.




     Data on the chronic toxicity of chlorpyrifos to saltwater animals are




available for the raysid, Mysidopsis bahia, and six fishes.  In the 28-day




life-cycle test with the mysid, survival and reproduction were reduced at




42 rig/L, and growth was significantly reduced at a nominal concentration




of 0.004 tig/L (McKenney et al.  1981).  This nominal concentration, which




was less than the limit of detection of the analytical method used, is




likely representative of the actual concentration because the test con-




centrations that could be measured averaged 10 * 2.5% of the nominal

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concentrations.  Of the six saltwater fishes exposed to chlorpyrifos in




early life-stage toxicity tests, the California grunion was the most




sensitive.  Decreased weight was the most sensitive endpoint for this




species (Goodman et al. 1985a), the sheepshead minnow (Gripe et al.




1986), and the gulf toadfish (Hansen et al. 1986).  Decreased survival




was the most sensitive endpoint with the three species of Menidia, although




growth was also affected with two of these species (Goodman et al. 1985b).




     The Species Mean Acute-Chronic Ratios for the seven saltwater species




range from 1.374 to 228.5, whereas that for the freshwater fathead minnow




is greater than 1,417.  However, the ratios for the five sensitive species




only range from 1.374 to 12.50.  Thus it seems reasonable to calculate




the Final Acute-Chronic Ratio for chlorpyrifos as the geometric mean of




these five.  Division of the freshwater and saltwater Final Acute Values




by the Final Acute-Chronic Ratio of 4.064 results in Final Chronic Values




of 0.04107 ijg/L and 0.005620 ,-ig/L, respectively.  The freshwater




value is about a factor of three lower than the 0.12 Mg/L that affected the




fathead minnow, which is an acutely insensitive species.  The saltwater




value is a factor of two higher than the chronic value for the most acutely




sensitive saltwater species, Mysidopsis bahia.






Toxicity to Aquatic Plants




     Several field studies have examined the effects of chlorpyrifos on




phytoplankton under more or less natural conditions (Brown et al. 1976;




Butcher et al. 1975,1977: Hughes et al. 1980; Hurlbert 1969; Hurlbert et




al. 1972; Papst and Boyer 1980).  All used an emulsifiable concentrate




of chlorpyrifos, which makes them inappropriate for inclusion in Table 4,




but the general trends identified are gerraaine to a discussion of the

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effects of chlorpyrifos under natural conditions.  With the exception of




Brown et al. (1976), all observed increased phytoplankton numbers after




application of chlorpyrifos.  This change is generally accepted not to be




a direct effect, but rather a result of changes in the herbivore-algal




relationship caused by large reductions in herbivorous zooplankton populations.




Papst and Boyer (1980) attempted to substantiate this hypothesis experimentally




by monitoring concentrations of pheopigments, the major chlorophyll degradation




product of herbivory, after chlorpyrifos application.  Although they found




reductions in pheopigments, the effect was delayed.  They did observe rapid




increases in the numbers of microzooplankton (e.g., rotifers) immediately




after chlorpyrifos application, presumably due to reduced competition




with macrozoopLankton.  Other studies have also observed an increase in




microzooplankton after chlorpyrifos treatment (Hughes 1977; Hur'lbert et




al. 1970,1972;. Siefert et ai. 1984).  Although increased phytoplankton




numbers might be explained by release from herbivory, another possible




factor is increased phosphate concentration from decomposition of chlorpyrifos




and from decomposition of intoxified organisms (Butcher et al. 1977).




     The concentrations of chlorpyrifos reducing growth or survival of




six saltwater species of phytoplankton range from 138 to 10,000 Mg/L




(Tables 4 and 6).   These concentrations are well above those that are




acutely lethal to saltwater animals.  Therefore, criteria derived using




data on the toxicity of chlorpyrifos to saltwater animals will probably




also protect saltwater plants.






Bioaccumulation




     Although chlorpyrifos is hydrophobic, which would suggest its




accumulation in tissues, this is offset by its rapid metabolism (Kenaga

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and Goring 1980; Marshall and Roberts 1978).  With the fathead minnow,




Jarvinen et al. (1983) found a mean bioconcentration factor (BCF) of 1,673




after 60 days (Table 5).  In a review, Kenaga and Goring (1980) cite




results of an unpublished study reporting a BCF in an unnamed fish of 450.




In an experimental outdoor stream, Eaton et al.  (1985) reported average




BCFs for a fathead minnow and a bluegill of 590 and 100, respectively, in




exposures ranging from 18 to 33 days.




     Data on the uptake of chlorpyrifos are available for five species of




saltwater fish (Table 5).  In two early life-stage tests with the gulf




toadfish, Opsanus beta, the BCF increased from 100 to 5,100 as the




concentration of chlorpyrifos in the test solution increased from 1.4 to




150 ,jg/L (Hansen et al. 1986).  Gripe et al. (Manuscript) found that the




BCF with the sheepshead minnow depended on the availability of food as




well as the concentration of chlorpyrifos in water (Tables 5 and 6).




     No U.S. FDA action level or other maximum acceptable concentration




in tissue is available for chlorpyrifos, and, therefore, no Final Residue




Value can be calculated.






Other Data




     Additional data on the lethal and sublethal effects of chlorpyrifos




on aquatic organisms are given in Table 6.  Because both chlorpyrifos and




the mosquitofish are used in mosquito control programs, several studies




have been conducted on the effects of chlorpyrifos on the survival and




effectiveness of mosquitofish as a predator of mosquito larvae.  Hansen




et al.  (1972) reported a 24-hr LC50 of 4,000 ^g/L for this fish.  A 36-hr




LC50 of 215 to 230 ^g/L was reported by Ferguson et al. (1966), whereas a




72-hr LC50 of 0.19 to 0.22 jg/L was reported by Ahmed (1977).  After a

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24-hr exposure to 5.0 pg/L, Johnson (1977a,1978a) observed a decreased




thermal tolerance in mosquitofish.  Hansen et al. (1972) found that




mosquitofish choae clean water when given a choice between clean water




and 100 ug chlorpyrifos/L in laboratory experiments.




     For rainbow trout, the 96-hr LCSOs at 1.6, 7.2, and 12.7'C were 51, 15,




and 7.1 Mg/L, respectively (Macek et al.  1969).  Increased toxicity of




chlorpyrifos with increased temperature was thought to be the result of




either increased metabolism producing lower concentrations of dissolved




oxygen and higher metabolic wastes, or increased enzyme activity converting




chlorpyrifos to its more toxic form, chlorpyrifos-oxon.  In a 24-hr




exposure to 100 ug/L, Atlantic salmon had a 4*C lower temperature preference




(Peterson 1976).




     Eaton et al. (1985) conducted studies on chlorpyrifos in outdoor




experimental streams containing native invertebrates, stocked fathead




minnows (Pimephales promelas) and bluegills (Le-pomis macrochirus), and




wild white suckers (Catostomus commersoni).  Two dosing strategies were




used in separate streams.  One was a continuous exposure; the other was a




pulsed exposure.  Concentrations were adjusted so that equal total amounts




of chlorpyrifos were applied to each stream.  Continuous exposure for 100




days to an average chlorpyrifos concentration of 0.35 pg/L (range 0.12




to 0.83 ug/L) produced no significant effect on the fishes.  The




invertebrate community was greatly effected, with a decrease in




species diversity and a strong shift from an amphipod- to an isopod-




dorainated benthic community.  Chironomids were greatly reduced.  BCFs for




the fathead minnow and bluegill were 590 and 100, respectively.  Continuous




and pulsed exposures gave similar results for most biological measurements.
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     Because of the previous use of chlorpyrifos as a mosquito larvieide,




many toxicity studies have used various species of mosquito Larvae as




test organisms.  Unfortunately, many studies have followed guidelines set




forth by the World Health Organization on testing of pesticides.  These




guidelines prescribe a 24-hr test duration, making results unusable for




derivation of water quality criteria.




     As would be expected, chlorpyrifos is highly toxic to mosquitos.




Rettich (1977) reported 24-hr LC50s of 0.5 to 3.5 >Jg/L for 4th instars




of 6 species of the genus Aedes.   For A. aegypt i, a species not tested by




Rettich, Saieh et al. (1981) cited 24-hr LCSOs of 0.0011 and 0.0014




>jg/L for 2nd and 4th instars, respectively.  Reports of 24-hr LC50s for 4th




instara of various Culex species range from 0.41 to 2.0 |Jg/L (Ahmed




1977; Kelson et al. 1979; Rettich 1977).  For C. pipiens, Saleh et al.




(1981) found a 24-hr LC50 of 0.0052 ,jg/L.




     Chlorpyrifos was also used to control noxious midge populations (Ali




and Mulla 1978a,1980; Mulla and Khasawinah 1969; Mulla et al.  1971;




Thompson et al. 1970).   The 24-hr LCSOs for various midges range




from 0,5 to 40 ,jg/L (Ali and Mulla 1978a,1980; Mulla and Khasawinah




1969) although a value of 1,470 ;Jg/L was reported for Cricotopus dedorus




(Ali and Mulla 1980).




     Ahmed (1977) determined 24-hr LCSOs with 6 species of aquatic coleoptera




and observed a range of 4.6 to 52 ,Jg/L.  Levy and Miller (1978) observed




the delayed effects of 24-hr exposures to 1.0 and 4.0 jJg/L on a planarian,




Dugesia dorotocephala,  over 108 hr.   They reported no significant effects




at either concentration.
                                   11

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     Winner et al. (1978) used a single concentration of an eraulsifiable




concentrate in a study of the effects on a me traithid nematode parasite of




mosquito larvae.  They examined toxicity to infectious, parasitic, post-




parasitic, and embryo stages of the nematode.  Rawn et al. (1978) investigated




the effect of various sediments on the toxicity of chlorpyrifos to larvae




of a mosquito in artificial ponds.  They found lower toxicity and lower




concentrations in water in sod-lined ponds compared to sand-lined ponds




at equal application rates.  Macek et al. (1972) conducted a field study




that included analyses of fish brain AChE activity, fish stomach contents,




residues in fish and water, numbers of larval insects, and numbers of




emerging insects.  Siefert et al. (1984) conducted an extensive survey of




changes within a natural pond after chlorpyrifos was applied using methods




employed by pest control authorities.  Their study included analysis of




water quality, fish and invertebrate populations, and associated laboratory




studies.




     Schaefer and Dupras (1970) examined the effect of polluted waters on




the stability of chlorpyrifos in the field.  Zepp and Schlotzhauer (1983)




studied the effect of algae on photolysis of chlorpyrifos.  As part of a




laboratory study, El-Refai et al. (1976) tested the effectiveness




of a simulated water treatment facility in lowering toxicity of Nile River




water spiked with chlorpyrifos.  They found a 33% decrease in toxicity




with alum treatment, and no significant change with sand filtration.




     Jamnback and Frempang-Boadu (1966), Mohsen and Mulla  (1981), and




Muirhead-Thomson (1978,1979) observed delayed effects after short exposures.




     Among saltwater species, juvenile brown shrimp, Penaeus aztecus,




were the most sensitive with a 48-hr EC50 of 0.32 ng/L (U.S. Bureau of




Commercial Fisheries 1965; Lowe et al. 1970).  Other 48-hr ECSOs are L.5




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,jg/L for juvenile grass shrimp, Palaemonetes pugio, 2.4 ,Jg/L  for the  pink




shrimp, Penaeus duorarum, and 5.2 ,jg/L for the blue crab, Callinectes sapidus




For the eastern oyster the 96-hr EC50s based on shell deposition range




from 270 to 340 tJg/L.




     The 48-hr LCSOs for fish ranged from 3.2 (Jg/L for the longnose




killifish, Fundulus similis, to over 1,000 Mg/L for the sheepshead minnow,




Cyprinodon variegatus.  The most sensitive effect on a fish species was a




reduction in growth of the California grunion, Leuresthes tenuis, exposed




to 0.62 rJg/L for 26 days (Goodman et al. 1985a).  Acetylcholinesterase




activity in the brain of adult mummichogs, Fundulus heteroclitus, was




inhibited by 2.1 Mg/L (Thirugnanam and Forgash 1977).




     The effect of chlorpyrifos on benthic communities was investigated




by Tagatz et al. (1982).  In communities exposed in the laboratory for 8




weeks during colonization, total faunal species richness and  the abundance




of arthropods and molluscs were reduced by concentrations from 0.1 to 8.5




,jg/L.  For communities previously colonized in the field, the number of




arthropods was reduced by 5.9 »Jg/L, but not by 1.0 ;Jg/L.






Unused Data




     Some data on the effects of chlorpyrifos on aquatic organisms were




not used because the studies were conducted with species that are not




resident in North America (e.g., Moorthy et al. 1982).  Results of tests




reported by Ali (1981), Ferguson et al. (1966), Naqvi (1973), and Nelson and




Evans (1973) were not used because the test organisms probably had been




previously exposed to pesticides or other pollutants.  Chiou  et al. (1977),




Dean and Ballantyne (1985), Kenaga (1980), Marshall and Roberts (1978),
                                    13

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Ramke (1969), Yoshioka et al.  (1986), and Zaroogian et al. (1985) only




contain data that have been published elsewhere.




     Data were not used if the test was on a commercial formulation (e.g.,




Ataliah and Ishak 1971; Birmingham and CoLman 1977; Chang and Lange 1967,




Hurlbert et al.  1970; Ledieu 1978; Muirhead-Thomson 1970; Hulla et al.




1973; Rettich 1979;  Roberts and Miller 1971; Scirocchi and D'Errae 1980,




Siefert et al. 1984; Smith et  al. 1966) or if the source of the chlorpyrifos




was not adequately described (e.g., Ali and Mulla 1976,1977; Boike and




Rathburn 1969; Gillies et al.  1974; Johnson 1977b,1978b; Kenaga et al.




1965; Micks and Rougeau 1977;  Muirhead-Thomson and Merryweather 1969;




Ruber and Kocor 1976; Thayer and Ruber 1976; Wilder and Schaefer 1969:




Zboray and Gutierrez 1979).  Data were not used if the organisms were




exposed to chlorpyrifos by injection or gavage or in food (e.g., Herin et




al. 1978; Wilton et  al. 1973), if chlorpyrifos was a component of a




mixture (Meyer 1981), or if the organisms were fed during exposure in




short term tests (Karnak and Collins 1974).




     The concentration of solvent was too high in the tests of Al-Khatib




(1985) and Davey et  al. (1976).  Barton (1970) conducted a static chronic




test with mosquito larvae.  Because polyethylene sorbs chlorpyrifos (Brown




et al. 1976; Hughes 1977; Hughes et al. 1980), toxicity tests conducted




in polyethylene test chambers  were not used if the concentration of chlor-




pyrifos was not  measured (e.g., Brown and Chow 1975; Darwazeh and Mulla




1974; Dixon and Brust 1971; Hughes 1977; Miller et al.  1973; Roberts et




al. 1973a,b).  Results of some laboratory tests were not used because the




tests were conducted in distilled or deionized water without addition of




appropriate salts (e.g., Jones et al. 1976; Nelson and Evans 1973;




Rongsriyam et al. 1968; Steelman et al. 1969).  High control mortalities




                                     14

-------
occurred in tests reported by Khudairi and Ruber (1974).  Test procedures were




inadequately described by Mellon and Georghiou (1985) and Ruber and Baskar (1969)




     BCFs obtained from microcosm or model ecosystem studies were not




used if the concentration of chlorpyrifos in water decreased with time or




if the exposure was too short (e.g., Metcalf 1974).  Data from field studies




and measurements of chlorpyrifos in wild organisms were not used if the




concentrations of chlorpyrifos in water were not measured (e.g., Ali and Mulla




1976,1977,1978a,b; Axtell et al. 1979; Best 1969; Campbell and Denno 1976;




Carter and Graves 1972: Chang and Lange 1967; Chatterji et al. 1979;




Cooney and Pickard 1974; Evans et al. 1975; Fitzpatrick and Sutherland 1978;




Frank and Sjogren 1978; Hazeleur 1971; Holbrook and Agun 1984; Hoy et al.




1972; Jamnback 1969; Lembright 1968; Linn 1968; Marganian and Wall 1972;




McNeil! et al. 1968; Moore and Breeland 1967; Mulla and Khasawihah




1969; Mulla et al. 1971: Nelson et al. 1976a,b; Polls et al. 1975; Roberts




et al.  1984; Steelman et al. 1969; Stewart 1977; Tawfik and Gooding 1970:




Taylor and Schoof 1971; Thompson et al. 1970; Wallace et al. 1973; Washino




et al.  I968,1972a,b; Wilkinson et al. 1971; Winterlin et al. 1968  Yap




and Ho 1977) or if the concentration in water was not uniform enough




(e.g.,  Macek et al. 1972).






Summary




     The acute values for eighteen freshwater species in fifteen genera




range from 0.11 >Jg/L for an amphipod to greater than 8U6 ,Jg/L for two




fishes  and a snail.  The bluegill is the most acutely sensitive fish




species with an acute value of 10 pg/L, but seven invertebrate genera are




more sensitive.  Smaller organisms seem to be more acutely sensitive than




larger  ones.






                                    15

-------
     Chronic toxi.ci.ty data are available for one freshwater species, the




fathead minnow.  Unacceptable effects occurred in second generation




larvae at 0.12 }Jg/L, which was the lowest concentration tested.  The




resulting acute-chronic ratio was greater than 1,417.




     Little information is available on the toxicity of chlorpyrifos to




freshwater plants, although algal blooms frequently  follow field applications




of chlorpyrifos.  The only available bioconcentration test on chlorpyrifos




with a freshwater species was with the fathead minnow and resulted in a




bioconcentration factor of 1,673.




     The acute toxicity of chlorpyrifos has been determined with 15




species of saltwater animals in 12 genera, and the acute values ranged




from 0.01 jg/L for the Korean shrimp, Palaemon macrodactylus, to 1,911




>jg/L for larvae of the eastern oyster, Crassostrea virginica.  Arthropods




are particularly sensitive to chlorpyrifos.  Among the 10 species of fish




tested, the 96-hr LC50s rans?e from 0.58 ,jg/L for striped bass to 520 >jg/L




for gulf toadfish; larvae are more sensitive than other life stages.




Growth of the mysid, Mysidopsis bahia, was reduced at 0.004 -,Jg/L in a




life-cycle test.  In early life-stage tests, the California grunion,




Leuresthes tenuis, was the most sensitive of the six fishes, with growth




being reduced at 0.30 ug/L.  Of the seven acute-chronic ratios that have




been determined with saltwater species, the five lowest range  from 2.388




to 12.50, whereas the highest is 228.5.




     Concentrations of chlorpyrifos affecting six species of saltwater




phytoplankton range from 138 to 10,000 pg/L.  BCFs ranged from 100 to




5,100 when the gulf toadfish was exposed to concentrations increasing from




1.4 to 150 ^ig/L.  Steady-state BCFs averaged from 1UO to 757 for five




fishes exposed in early life-stage tests.




                                    16

-------
National Criteria




     The procedures described in the "Guidelines tor Deriving Numerical




National Water Quality Criteria for the Protection of Aquatic Organisms




and Their Uses" indicate that, except possibly where a locally important




species is very sensitive, freshwater aquatic organisms and their uses




should not be affected unacceptably if the four-day average concentration




of chlorpyrifos does not exceed 0.041 ,Jg/L more than once every three years




on the average and if the one-hour average concentration does not exceed




0.083 ,Jg/L more than once every three years on the average.




     The procedures described in the "Guidelines for Deriving Numerical




National Water Quality Criteria for the Protection of Aquatic Organisms




and Their Uses" indicate that, except possibly where a locally important




species is very sensitive, saltwater aquatic organisms and their uses




should not be affected unacceptabLy if the four-day average concentration




of chlorpyrifos does not exceed 0.0056 ,Jg/L more than once every three years




on the average and if the one-hour average concentration does not exceed




0.011 pg/L more than once every three years on the average.




     Three years is the Agency's best scientific judgment of the average




amount of time aquatic ecosystems should be provided between excursions




(U.S. EPA 1985b).   The resiliences of ecosystems and their abilities to




recover differ greatly, however, and site-specific allowed excursion




frequencies may be established if adequate justification is provided.




     Use of criteria for developing water quality-based permit limits and




for designing waste treatment facilities requires selection of an appropriate




wasteload allocation model.  Dynamic models are preferred for the application




of these criteria (U.S. EPA 1985b).  Limited data or other considerations




might make their use impractical, in which case one must rely on a steady-




state model (U.S.  EPA 1986).



                                    17

-------
                       Table 1.   Acute ToxicIty  of  Ch.lorpyr 11os  to Aquatic Anhuls
Spec Us
 Snail  (adult),
 Aplexa hypnoruro

 Amphlpod,
 Ganvnarus  fasclatus

 Amphlpod  (2 mo. old),
 Gammarus  IacustrIs

 Amphlpod,
 Gammarus  pseudolImnaeus

 Crayfish  (1.8 g) ,
 Orconectes Immunls

 Stonefly  (naiad),
 Pteronarcella bad la

 Stonefly  (naiad),
 Pteronarcys callfornlca

 StonefIy  (naiad),
 Claassenla sabulosa

 Tr Ichopteran,
 Leptocertdae sp.

 Pygmy  backswlmner,
 Neoptea strlola

 Pyqmy  backswlmmer,
 Neoplea strlola

CrawlInq water beetle
 (adult),
Pel todytes sp.

 Cutthroat  trout (1.4 g),
 Salmo clarkl1
                            LC50      Spec I M Mean
                          or EC50     Acute Value
Method*    Chemical"    (nfl/L)***      (»g/L)
                                            FRESHWATER  SPECIES
 F, M


 S, U


 S, U


 F, M


 F, M


 S, U


 S, U


 S, U


 S, M


 S, M


 S. M


 S, U



 S, U
Technical
 (98.7*)

Techn leal
Technical
  (97*)

Encapsu-
lated**"

Technical
 (98.7J)

Techn leal
  <97<)

Technical
  (97*)

Techn leal
  (97*1

Encapsu-
lated**"

Encapsu-
lated****

Encapsu-
lated****
Techn leal
  (97O
>806
>«06
   0.32


   0.11


   0.18


   6


   0.38


  10


   0.57


   0.77


   1.22


   1.56


   0.8



  18
   0.32


   0.11


   0.18


   6


   0.38


  10


   0.57


   0.77





   1.38


   0.8



  18
                                           Refer MIC*
Phlpps and HoI combe
I985a,b

Sanders 1972
Sanders 1969; Johnson
and Flnley 1900

Sletert et al. 1984
Phlpps and Ho I combe
I9ti5a,b

Sanders and Cope 1968
Sanders and Cope 1968;
Johnson and Flnley I960

Sanders and Cope 1968;
Johnson and Flnley 1980

Slefert et al. 1984
Slefert et al. 1984
Slefert et al. 1984
                                           Federle and Col I Ins
                                           1976
Johnson and Flnley I960
                                                                                       18

-------
Table I.  (continued)
Species
Rainbow trout (0.6-1.5 g),
Salmo galrdnerl
Rainbow trout (juvenile),
Salmo qalrdnerl
Rainbow trout (3.0 g) ,
Salmo qalrdner 1
Lake trout (2.3 g) ,
Salvellnus namaycush
Goldfish (10.7 g),
Carasslus auratus
Fathead minnow,
Plmephales promelas
Fathead minnow (juvenile),
Plmephales promelas
Fathead minnow (0.5 g) ,
Plmephales promelas
Channel catfish (0.8 g),
Ictalurus punctatus
Channel catfish (7.9 g) ,
Ictalurus punctatus
Blueqll 1 (0.6 q) ,
Lepomls macrochlrus
Blueqll! (0.8 g) ,
Lepomls macrochlrus
Method*
S, U
F, M
Fu
• n
S, U
F, M
S, M
F, M
F, M
S, U
F, M
S, U
F, M
Chemical**
Techn leal
Techn leal
(99.9*)
Techn leal
(98.7*)
Techn leal
(97*)
Techn lea!
(98. 7<)
Techn leal
(98.7*)
Technical
(99. 9<)
Techn leal
(98.7*)
Techn leal
(97*)
Techn leal
(98.7*)
Technical
(97*)
Techn leal
(98.7*)
LC50
or EC50
7.1
8.0
9
98
>806
170
203
542
280
806
2.4
10
Species Mean
Acute Value
(ii9/L> Reference
Macek et al . 1969;
Johnson and Flnley 1980
Hoi combe et al . 1982
8.485 Phlpps and Ho! combe
I985a,b
98 Johnson and Flnley 1980
>806 Phlpps and Ho! combe
1985a,b
Jarvlnen and Tanner
1982
Ho I combe et al . 1982
331.7 Phlpps and Hoi combe
1 985a , b
Johnson and Flnley 1980
806 Phlpps and Hoi com be
1985a,b
Johnson and Flnley 1980
10 Phlpps and Ho Icon be
1985a,b
                                         19

-------
Table 1.  (Continued)
Species
Eastern oyster (larva),
Crassostrea virgin lea
Mysld ( juvenile) ,
Mysldopsls bah la
Mysld ( juven lie) ,
Mysldopsls bah la
Am phi pod ,
Ampel Isca abdlta
Am phi pod,
Hhepoxynlus abronlus
Amph 1 pod ,
RhepoxynJus abronlus
Korean shrimp (adult),
palaemon macrodacty I us
Korean shrimp (adult),
Palaemon macrodacty lus
Gulf toad fish (juvenile),
Opsanus beta
Sheepshead minnow
(juvenile) ,
Cyprlnodon varlagatus
Sheepshaad minnow
( juvenile) ,
Cyprlnodon varleqatus
Mummlchoq (adult),
Fundulus heterocl Itus
Method*
S. U
S, U
f, M
R, U
R, U
R, U
S, U
f. 0
R, M
S, U
F, M
S, U
Che»)cd)««
Tochn leal
(921)
Techn leal
(92<)
Techn leal
(92<)
Techn leal
(92*)
Technical
(92<)
Techn leal
(92<)
(99*)
Techn leal
(92*)
Techn leal
(92*)
Techn leal
(92*)
Techn leal
(99.5*)
Salinity
(g/Kg)
SALTWATER
20
20
26.7
32
32
32
It)
24
29-30
20
10.3
20-25
LC50 Species Hean
or EC50 Acute Value
<(ig/L)*** (pgA)
SPECIES
1,991 1,991
0.056
0.035 0.035
0.16 0.16
0.07
0.14 0.0990
0.25
0.01 0.05
520 520
270
136 136
4.65 4.65
Reference

Borthwlck and Walsh 1981
Borthwlck and Walsh 1981
Schlnwnef et al . >9tt3
Scott and Redmond 1986 a
Scott and Redmond 1986b
Scott and Redmond 1986b
Earnest 1970
Earnest 1970
Han sen et al . 1986
Borthwlck and Walsh 1981
Schlromel et al . 1983
Thlrugnanam and forqasn
1977
                                                    20

-------
Table 1.  (Continued)
Species
Lonqnose kl 1 1 1 1 Ish
(juvenile) ,
Fundulus slrnl 1 Is
Cal If on la qr union
(day 0 larva),
Leuresthes tenuls
California qrunlon
(day 7 larva) ,
Leuresthes tenuls
California qrunlon
(day 14 larva) ,
Leuresthes tenuls
Cal Horn la qrunlon
(day 28 larva) ,
Leuresthes tenuls
Cal Ifornla qrun Ion
(day 0 larva) ,
Leuresthes tenuls
Cal Ifornla grunlon
(day 7 larva) ,
Leuresthes tenuls
Cal Ifornla qrunlon
(day 14 larva),
Leuresthes tenuls
Cal Ifornla qrunlon
(day 28 larva) ,
Leuresthes tenuls
inland sllverslde
( juvenl le) ,
Men Id la beryl 1 Ina
Atlantic sllverslde
(day 0 larva) ,
Method* Chemical"*
F, M Technical
(92*)
S, U Technical
(92<)
S, U Technical
(92*)
S, U Technical
(92*)
S, U Technical
(92*)
F, M Technical
(92*)
F, M Technical
(92<)
F. M Technical
(92*)
F, M Technical
(92i)
F, M Technical
S, U Technical
(92*)
LC50 Species Mean
Salinity or EC50 Acute Value
(g/kg) **a (n9/L)
25.9 4.1 4.1
23 5.5
25 2.7
25 1.8
25 2.6
25 1.0
25 1.0
25 1.0
25 1.3 1.068
5.0 4.2 4.2
20 4.5
Reference
Schlmmel
BorthwlcK
borthwlck
Borthwlck
Borthwlck
Borthwlck
Borthwlck
Borthwlck
Borthwlck
Clark et
Borthwlck
et al . 1983
et al. 1985
et al . 1985
et al. 1985
at al . 1985
et al . 1985
et al . 1985
et al . 1985
et al. 1985
al. 1985
et al . 19H-3
Men Id la men Id la
                                                             21

-------
Table  1.  (Continued)
Species
Atlantic silvers Ida
(day 7 larva) ,
Men Id la men Id la
Atlantic sllverslde
(day 14 larva).
Men Id la men Id la
Atlantic sllverslde
(day 28 larva) ,
Men Id la men Id la
Atlantic sllverslde
( j uven 1 1 e)
Menldla menld (a
Atlantic sllverslde
(day 0 1 arva) ,
Men Id la men Id la
Atlantic sllverslde
(day 7 larva) ,
Men Id la menldla
Atlantic sllverslde
(day 14 larva) ,
Menldla menldla
Atlantic sllverslde
(day 28 larva) ,
Menldta menldla
Tidewater sllverslde
(day 0 larva) ,
Menldla peninsulas
Tidewater sllverslde
(day 7 larva) ,
Menldla penlnsulae
Tidewater sllverslde
(day 14 larva) ,
Method*
S, U
s, u
S, U
F, M
F, M
F, M
F, M
F, M
S. U
S, U
s, u
Chealcal**
Techn leal
(92%}
Techn leal
(92*)
Techn leal
(92*)
Tachn leal
(921)
Technical
(92*)
Techn leal
(92<)
Techn leal
(92<)
Techn leal
(92*)
Technical
(92*)
Techn leal
(92*)
Technical
(92*)
LC50 Species Mean
Salinity or ECSO Acute Value
<9Ag) (na/D"* (iiQ/D
20 2.8
20 2.4
20 4.1
24.3 1.7
20 0.5
20 1 .0
20 1.1
20 5.0 1.229
20 4.2
20 2.0
20 l.b
Reference
Borthwlck et al
Borthwlck et al
Brothwlck et al
Schlmmel et al .
Borthwlck et al
Borthwlck et al
Borthwlck et al
Borthwlck et al
Borthwlck et al
Borthwlck at al
Borthwlck et al
. 1985
. 1985
. 1985
1983
. 1985
. 1985
. 1985
. 1985
. 1985
. 1985
. 1985
Menldla penlnsulae
                                                        22

-------
Table I.  (Continued)
Species Method*
Tidewater sllverslde S, u
(day 28 larva) ,
Men Id la penlnsulae
Tidewater sllverslde f, M
(day 0 larva) ,
Menldla penlnsulae
Tidewater sllverslde F, M
(day 7 larva) ,
Menldla penlnsulae
Tidewater sllverslde F, M
(day 14 larva) ,
Menldla penlnsulae
Tidewater sllverslde F, M
(day 28 larva) ,
Menldla penlnsulae
Tidewater sllverslde F, M
( j uven He),
Menldla penlnsulae
Striped bass (juvenile), F, U
Morone saxat Ills
Striped mullet (juvenile), F, M
Muql 1 cephalus
Che* leal**
Techn leal
(921)
Techn )cat
(92<>
Techn leal
(92*)
Techn leal
192*)
Techn leal
(92O
Techn leal
(99$)
Techn leal
(92O
Salinity

-------
                            Table 2.  Chronic ToxicIty of Chlorpyrlfos to Aquatic Animals
Spec Us
Test*     Chemical**
Salinity     Limits
 
Technical
(92<)
Technical
(92<)
Technical
(92O
Techn leal
(921)
Techn leal
(92O
Techn leal
(92O
Technical
(921)
FRESHWATER SPECIES
1.6-3.2
f - 2.2-4.8
f - b
et al . I985b
                                                         24

-------
Table 2.  (Continued)
Species
Tidewater sllverslde.
Men Id 1 a penlnsulae

Test*
ELS
Chemical"*
Techn teal
(92*)
Salinity
(g/Kg)
18-25
Limits
(Mg/L)«*«
0.38-0.78
Chronic Value

0.5444
Reference
Goodman et al .
19856
*   LC = life-cycle or partial life-cycle; ELS = early life-stage.



**  Percent purity Is given  In parentheses when available.



*** Results are based on measured concentrations of chlorpyrl fos.



*   The test material was dissolved from an encapsulated  form of chlorpyr 1 fos.



tt  Unacceptable effects occurred at all tested concentrations.
                                           25

-------
Table 2.  (Continued)
                                                  Acute-Chronic Ratio
Acute Value
Species (pg/L)
Fathead minnow,
Plmephales promelas
Mysld,
Mysldopsls bah la
Gulf toad fish,
Opsanus beta
Sheepshead minnow,
Cyprlnodon varlegatus
Sheepshead minnow,
Cyprlnodon varlegatus
Sheepshead minnow,
Cyprlnodon varlegatus
California qrunlon,
Leuresthes tenuls
Inland sllverslde.
Men Id la beryl 1 Ina
Atlantic sllverslde,
Men Id la men Id la
Tidewater sllverslde.
Men Id la penlnsulae

170
0.035
520
136
136
136
1.068
4.2
1.229
0.7479
Chronic Value
<0.12*
0.0028
2.276
2.258
2.258
2.258
0.2049
1.162
0.3666
0.5444
Ratio
>,,4,7
12.50
228.5
60.23
60.23
60.23
5.212
3.614
3.352
1.374
                           *  Results of the early life-stage tests are not  used  because results
                             of a life-cycle test are available.
                                                                     26

-------
Table 3.  Ranked Genus Mean Acute Values with Species  Mean Acute-Chronic Ratios
tank*
15
14
13
12
11
10
9
8
7
6
5
A
Genus Mean
Acute Value
(iiQ/L)
>806
>806
806
331.7
98
12.36
10
10
6
1.38
0.8
0.77
Species
FRESHWATER SPECIES
Snail,
Aplexa hypnorum
Goldfish,
Carasslus auratus
Channel catfish,
Ictalurus pufictatus
Fathead minnow,
Plmephales promelas
Lake trout,
Salvellnus namaycusn
Cutthroat trout,
Salmo clarkl
Rainbow trout,
Salmo (jalrdnerl
Stonef ly,
Pteronarcys cal Horn lea
Blueqll 1,
Lepotnls macrochlrus
Crayfish,
Orconectes Immunls
Pyqmy backs wlmmer,
Neoplea strtola
Crawling water beetle,
Peltodytes sp.
Tr Ichoptara
Species Mean
Acute Value
(M9/L)"*
>806
>806
806
331.7
98
18
8.485
10
10
6
1.38
0.8
0.77
Species Mean
Acute-Chron Ic
Ratio"*
>1,4I7
                      LeptocerJdae  sp.
                                           27

-------
Teble 3.  (continued)
Rank*
3
2
1


12
II
10
9
8
7
Genus Mean
Acute Value
(»g/L> Species
0.57 Stonatly,
Claasenla sabulosa
0.38 Stonatly,
Pteronarcel la bad! a
0.1850 Amphlpod,
Gamnarus fasclatus
Amph 1 pod ,
Gammarus lacustrls
Amphlpod,
GanMiarus psaudol Imnaeus
SALTMATER SPECIES
1,991 Eastern oyster,
Crassostraa virgin lea
520 Gulf toad fish.
Opsanus beta
136 Sheepshead minnow,
Cyprlnodon varlagatus
5.4 Striped mullet,
Mug II cephalus
4.366 HuMinlchog,
Fundulus heteroclltus
Longnose kll 1 Iflsh,
Fundulus slMl 1 Is
1.569 Inland sllversicte.
Men Id la beryl Una
Atlantic sllverslde,
Man Id la menldla
Tidewater sllverslde.
Species MMM
Acute Value
da/I.)"
0.57
0.38
0.32
o.n
0.18

1.991
520
136
5.4
4.65
4.1
4.2
1.229
0.7479
Species NRM
Acute-Chronic
Retlo"*
:
-
-

-
228.5
60.23
-
3.614
3.352
1.374
                          Men Id la  peninsulas
                                                          28

-------
 Table 3.  (continued)
Rank*
-•••m-v
6
5
4
3
2
1
Genus Mean
Acute Value

-------
                                 •Table 4.   ToxicIty of Chlorpyrlfos to Aquatic Plants
Species
Duration
Chemical* (days)
Sa 1 1 n 1 ty Concentr at Ion
 Effect (Mg/L)** Reference
SALTWATER SPECIES
Golden-brown alqa,
Isochrysls gal bang
0 1 atom ,
Skeletonema cost a turn
0 1 atom ,
Thalassloslra pseudonana

Technical 4
(92%)
Technical 4
(92*)
Technical 4
<92f)
30 EC50 (popla-
1 at Ion growth)
30 EC50 (popula-
1 at Ion growth)
30 EC50 (popula-
1 at Ion growth)
138 Borthwlck and
iyei
297. Q*** Borthwlck and
1961
148 Borthwlck and
1981
Walsh
Walsh
Walsh
*   Percent purity Is given  In  parentheses  when  available.

**  If the concentrations  ware  not  measured and  the  published  results ware not reported  to be adjusted for purity,
    tha published results  were  multiplied by  the purity  If  It  was  reported to be less than 97$.

*** Geometric mean of  five values.
                                                         30

-------
Table 5.  BloconcentratJon  of  Chlorpyrlfos  by Aquatic Organisms
Species
Fathead minnow,
Plmephales promelas
Fathead minnow,
Plmephales promelas
Fathead minnow,
Plmephales promelas
Fathead minnow,
Plmephales promelas
Fathead minnow,
Plmephales promelas
Blueqil 1,
Lepomls macrochlrus
Gulf toadflsh.
Opsanus beta
Sheepshead minnow,
Cyprlnodon varleqatus
Cal Ifornla gr union,
Leuresthes tenuls
California grunlon,
Leuresthes tenuls
Inland sllverslde.
Men Id la beryl 1 tna

Chemical*
Encapsulated^
-
-
-
-
Technical
192%)
Techn leal
(92*)
Technical
(92%)
Technical
(92%)
Technical
(921)
Concentration
In Water ((.p/D**
FRESHWATER
0.12-2.68
0.14
0.15
0.32
0.46
0.41
SALTWATER
1.4
0.41
0.78
0.14-0.63
0.28-1.3
0.18-1.8
Durat Ion
(days)
SPECIES
60
21
18
21
33
33
SPECIES
49
28
35
26
28
Tissue
Whole
body
Whole
body
Whole
body
Whole
body
Whole
body
Whole
body
Whole
body
Whole
body
(n=6)
Whole
body
(n-3)
Whole
body

-------
Table 5.  (continued)
Species
Tidewater sllverslde,
Hen Id la penlnsulae

Chen leal*
Techn lea 1
(92$)
Concentrat ton
In Mater (Mg/L)«»
0.093-0.38
Duration
(days)
26
Tissue BCF or BAF***
Whole 456ft
body
(n=5)
Reference
Goodman et at . 1985b
*    Percent purity  Is given  In  parentheses  when  callable.

**   Measured concentration of chlorpyrIfos.

***  Bloconcantratlon  factors (BCFs) and  bloaccunulatlon factors (BAFs)  are based on (Measured concentrations ot chlorpyr Itos In wotar
     and tissue.

*    The test material Mas dissolved  from an  encapsulated form of chlorpyr Ifos.

**   Geometric mean  of values  from  the  listed  concentrations In water.
                                                                32

-------
                           Table 6.  Other Data OM Effects of Chlorpyrlfos on Aquatic Organ IM
Species
Chemical*
                               Coacentratlom
                                  <»fl/U**     Reference
FRE5HMATER SPECIES
Diatoms,
Unidentified
Planar Ian,
Doges I a dorotocepha 1 a
Cladoceran,
Daphnla sp.
Am phi pod,
Hyalel la azteca
Mayfly,
Ephemere! la sp.
Pygmy backs* limner,
Neoplea strlola
Giant water bug (adult),
Belostoma sp.
Predaceous diving beetle
(adult),
Hygrotus sp.
Predaceous diving beetle
(adult),
Laccophllus dec Ip lens
Predacaous diving beetle
(adult),
Thermonectus bat 1 liar Is
Mater scavenger beetle
(adult),
Berosus styllferus
10 days
24 hr
Encapsulated*** 4 hr
Encapsulated*** 24 hr
Encapsulated*** 72 hr
Encapsulated*** 144 hr
Technical 24 hr
Technical 24 hr
Technical 24 hr
Technical 24 hr
Technical 24 hr
Reduced
groat h
None
LC50
LJC50
LC50
LC50
LC50
LC50
LC50
LC50
LC50
400 Roberts and MM
4.0 Levy and Miller
0.88 Slefert et al .
1.28 Slefert et al .
0.33 Slefert et al .
0.97 Slefert et al .
15 Ahmed 1977
40 Ahmed 1977
4.6 Ahmed 1977
6 Ahmad 1977
9 Ahmed 1977
ler 1
1978
1984
1984
1984
1984

Mater scavenger beetle
(larva),
Hydrophllus triangular Is
Technical
24 hr
L£50
20
Ahmed 1977
                                                          33

-------
 Table 6.  (continued)
 Species
Chemical*      Duration      Effect
Concentration
   (•a/I)"    Reference
Mater scavenger be«tle
(adult),
HydrophUus trlnnqulnrls
Mater scavenger beetle
( larva),
Troplsternus lateral Is
Mater scavenger beetle
(adult),
Troplsternus lateral Is
Mosquito (3rd and 4th
In star),
Aedes aeqyptl
Mosquito (2nd Instar) ,
Aedes aegyptl
Mosquito (4th Instar),
Aedes aegyptl
Mosquito (4th Instar),
Aedes cantans
Mosquito (4th Instar),
Aedes communl*
Mosquito (4th Instar),
Aedes excruclans
Mosquito (4th Instar),
Aedes punctor
Mosquito (4th Instar) ,
Aedes stlctlcus
Mosquito (4th Instar),
Aedes vexans
Mosquito ( larva) ,
Technical
Technical
Techn leal
Techn leal
Technical
(96* )
Technical
(961)
Techn leal
Techn leal
Techn leal
Techn leal
Techn leal
Techn leal
Teehn leal
24 hr
24 hr
24 hr
IB hr
24 hr
24 hr
24 hr
24 hr
24 hr
24 hr
24 hr
24 hr
24 hr
UC50
l£50
UC50
LT50
UC50
UC50
UD50
LC50
LC50
LC50
LC50
LC50
LC50
30
52
8
10
0.0011
0.0014
1.1
3.5
3.3
2.7
0.5
1.0
3
Ahmed 1977
Ahmed 1977
Ahmed 1977
Verma and Rahman 1984
Sal eh et al . 1981
Sal eh et al . 1981
Rettlch 1977
Rettlch 1977
Rettlch 1977
Rettlch 1977
Rettlch 1977
ftettlch 1977
Ahmed 1977
Anopheles freebornl
                                                   34

-------
Table 6.  (continued)
Species
Chemical*
Duration
Effect
                                                                            Concentration
Instar),
Culex quinguefasclatus
Reference
Mosquito (4th Instar),
Anopheles freeborni









Mosquito (3rd and 4th
instar),
Anopheles Stephens 1
Phantom midge.
Chaoborus sp.

Mosquito (4th Instar),
Culex pip lens
Mosquito (2nd Instar;
DDT susceptible),
Culex pipiens
Mosquito (4tti Instar;
ODT susceptible),
Culex pipiens
Mosquito (4th Instar),
Culex plpiens
Mosquito (4th Instar) ,
Culex pipiens
Mosquito (3rd and 4th
Technical 24 hr LC50










Technical 6.5 hr LT50


Encapsulated*** 18 hr LC50
42 hr LC50
114 hr LC50
Technical 24 hr EC50
(99J
Technical 24 hr LC50
(96*)

Technlcdl 24 hr LC50
(961)

Technical 24 hr LC50

Technical 24 hr LC50

Technical 5 hr LT50
1.3
0.9
2.5
.2
.2
.9
.3
.2
2.8
3.3
7.0
25


2.36
1.29
0.85
0.46

0.0022


0.0052


1.2

1.6

10
WomeMorf et al . 1970










Verma and Rahman 1984


Sfefert et al . 1984


Nelson et al. 1979

Saleh et al . 1981


Saleh et al . 1981


Rettlch 1977

Rettlch 1977

Verma and Rahman 1984
                                                   35

-------
Table 6.   (continued)
Specie*
Mosquito (4th Instar),
Culex restuans
Mosquito < larva) ,
Culex tor sal Is
Mosquito (4th Instar),
Cul Iseta annul ata
Midge (4th Instar),
Chlronomus sp.
Midge (4th Instar),
Chtrononus decor us
Midge (4th Instar),
Chlrononus utahensls
Midge (4th Instar) ,
Crtcotopus decorus
Midge (4th Instar),
Olcrotendlpes callfornlcus
Midge (4th Instar),
Goal dlch Iron omus
holoprasslrws
Midge (4th Instar) ,
Procladlus spp.
Mldga (4th Instar),
Tanypus grodhausl
Mldga (4th Instar),
Tanypus grodhausl
Mldga (4th Instar),
Tanygus grodhausl
Rainbow trout,
SalMo galrdnerl
Chealcal*
Technical
(99f)
Duration
••••^eMBMmw
24 hr
Techn leal
Techn
Techn

Techn

Techn

Techn

Techn

Techn


Techn

Techn

leal
leal

leal

leal

leal

leal

leal


leal

leal

Techn leal

Techn

Techn


leal

leal

24
24

24

24

24

24

24


24

24

24

24

96

hr
hr

hr

hr

hr

hr

hr


hr

hr

hr

hr

hr

Effect
LC50
LC50
LC50
LC50

LC50

UC50

UC50

UC50

LC50


LC50

IC50

1C 50

l£50

LC50 (7.2*C)
(I.6*C)
Concentration
<»oA)** Reference
0.41 Hal son et al . 1979
2
3.5
0.42

7.0

1.2

1,470

40.0

0.97


0.5

29.0

0.5

5.7

15
51
Ahmed 1977
ftettlch
Mul

Al 1

All

All

All

Mul


All

All

Mul

Mul

1977
la and Khasawlnah

and

and

and

and


Mul

Mul

Mul

Mul


la I978a

la I978a

la 1980

la 1980

la and Khasawlnah


and

and



Mul

Mul



la 1978a

la 1980

la and Khasawlnah



la and Khasawlnah


Macek et al




. 1969

1969









1969






1969

1969



                                                      36

-------
Tattle 6.  (continued)
Specie*
Chemical*      Duration
Effect
Concentratloii
   <»fl/L>*a     Reference
Atlantic salmon (juvenile),
Salmo salar
Golden shiner,
Notemlgonus crysoleucas
Golden shiner,
Notemlgonus crysoleucas
Fathead minnow,
Plmaphales promelas
Fathead minnow,
Plmephales promelas
Fathead minnow,
Plmephales promelas
Fathead minnow (larva),
Plmephales promelas
Mosquito fish,
G ambus la afflnls
Mosquito fish
(DOT susceptible),
G ambus la afflnls
Mosquito fish
(DOT resistant),
G ambus la afflnls
Mosquito fish,
G ambus la afflnls
Mosqultoflsh (adult),
G ambus la aff Inls

Mosquito fish,
G ambus la afflnls
Technical 24 hr
O95*)
Techn leal 36 hr
(99f)
Techn leal 36 hr
(99 *)
Technical"*** 96 hr
Encapsulated*** 96 hr
Encapsu- 96 hr
lated***, *•**
7 day
Technical 48 hr
Technical 48 hr
24 hr
Technical 72 hr
Techn leal 36 hr
(99*)
Temperature
selection
LC50
LC50
l£50
LC50
1C 50
ftoducod growth
Avoidance
UC50
LC50
Decreased
thermal tolerance
UC50
LC50
100
45
35
150
130
280
5.2
100
1,018
1,291
5
0.22
0.20
0.20
0.19
0.20
0.20
230
215
Peterson 1976
Ferguson et at . 1966
Ferguson et al . 1966
Jarvinen and Tanner
Jarv Inen and Tanner
Jarvinen and Tanner


1982
1962
1962
Norbarg and Mount 1985
Hansen et at . 1972
Cul ley and Ferguson
Culley and Ferguson
Johnson 1978a
Ahmed 1977
Ferguson et al . 1966
1969
1969

                                                         37

-------
Tatole 6.  (continued)
Concentration
Species
Mosquito fish,
Gambusla at tin Is
Guppy,
Poecllla ret 1 cut at a
Green sun fish.
Lepomls cyanel lus

Species
Cham leal*
—

Techn leal

Techn leal
(99<)

Chemical*
Duration
24 hr

24 hr

36 hr

Salinity
(g/kg) Duration
Effect
LC50

LC50

LC50

(u9/L)**
4,000

220

37.5
22.5
Reference
Hansen et al . 1972

Rongsrlyam et al . 1'

Ferguson et al . 1961

Concentrat ton
Effect
(nfl/D**
Reference
SALTWATER SPECIES
Green alga.
C h 1 orococcum sp .
Diatom,
Skeletonema costatum
Diatom,
Amphlprora sp.
Olnof lagel late.
Gonyaulax sp.
Benthtc macrofauna








Benthlc macrofauna

—

Technical
<92<)
_

-

Technical
(92O







Technical
(92*)
27 48 hr

30 48 hr

27 46 hr

27 48 hr

26.5 8 wk
(14.5-34.0)







27.5 1 wk
(18.0-32.5)
Reduced
growth
IOOJ mortal Ity

Reduced
growth
Reduced
growth
Significant reduc-
tion In total
faunal species
r Ichness and In
abundance of
arthropods and
molluscs for
1 aboratory-colon-
tzed benthos
Significant reduc-
tion In abundance
10,000

5,000

10,000

10,000

0.1








5.9

Maly and Ruber 1983

Walsh 1981,1983

Maly and Ruber 1983

Maly and Ruber 1983

Tagatz et al . 1982








Tagatz et al . 1982

                                                                    of arthropods  for
                                                                    field-colonized
                                                                    benthos
                                                        38

-------
Table 6.  (continued)
Spec Us
Eastern oyster
( juvenile) ,
Crassostrea virgin lea
Eastern oyster
(juvenile) ,
Crassostrea virgin lea
Am phi pod,
Ampel Isca abdlta
Brown shr Imp
Chew lea I1
<99<)
(99%)
(92%)
(99%)
Sa 1 1 n I ty Concentr at ton
(g/kg) Duration Effect (|ig/L)" Reference
24 96 hr EC 50 (shel I
deposition)
28 96 hr EC50 ( shel 1
deposition)
32 96 hr EC50 (with
sed Intent)
26 48 hr EC50 (mortal Jty
270 U.S. Bureau of Commercial
Fisheries 1965; Lowe et al
1970
54 U.S. Bureau of Commercial
Fisheries 1967
0.34 Scott and Redmond 1986 a
0.20 U.S. bureau of Commercial
(juvenl le),
Penaeus aztecus

Pink shrimp                  (99*)
(juvenile),
Penaeus duorarum

Grass  shrimp                 (99f)
(j uven lie),
Palaemonetes puglo

Grass  snrImp (adult),        (991)
Palaemonetes puglo

Blue crab (juvenile),        (991)
Calltnectes sapldus

Atlantic salmon             <>95<)
(juven lie) ,
Salmo salar

Sheepshead minnow          Technical
(juvenile),                  192%)
Cyprlnodon varlegatus
Sheepshead minnow            (991)
(adult),
Cyprlnodon varleqatus
                       and loss of
                       equl I Ibr lum)

  26        48 hr      EC50
  26        48 hr      EC50 (mortality
                       and loss of
                       equlIIbr lum)

  20         I hr      No avoidance
                       of pesticide

  20        43 hr      EC50
            24 hr      Altered preferred
                       temperature
9-10        28 days    BCF = 42-660
                       ( low food);
                       69-1.000 (med.
                       food);  120-1,630
                       (high food)

  20         I hr      Avoidance of
                       pesticide
             Fisheries 1963;  Lowe et al
             1970

     2.4     U.S. Bureau of Commercial
             Fisheries 1967
             U.S. Bureau of Commercial
             Fisheries 1967)
0.01-1.0     Hanson et al. 1973
     5.2     U.S.  Bureau of Commercial
             Fisheries 1967

 100-250     Peterson 1976
0.41-52      Crlpe et al . 1986
 100-250     Hansen 1969,1970
                                                            39

-------
Table 6.   (continued)
                                             Salinity
ConcentratIon
Species
Sheepshead minnow
(juvenile) ,
Cyprlnodon varlegatus
Gulf toad fish,
Opsanus beta
Mummlchog (adult),
Fundulus heteroclltus
Chemical*
(99»)
(921)
Techn leal
(99.5O
(g/kg)
24
24-34
20-25
Duration
48 hr
49 days
24 hr
Effect (pg/L)**
LC50 >1,000
BCF = 100- 1.4-150
5,100
1001 Inhibition >2.1
of acetylchol In-
Reference
U.S. Bureau of Commercial
Fisheries 1967
Han sen et al . 1986
Thlrugnanam and Forgash
1977
Lonqnose kllllflsh           (99J)
(juven lie) ,
Fundulus slmllls

California qrunion,        Technical
Leuresthes tenuls            (92$)
Spot (juvenile),             (99*)
Lelostomus xanthurus
                                                                     esterase  activity
                                                                     In  brain

                                               24        48  hr       LC50
                                               24.5-       26  days     Significantly
                                               31.5                   reduced growth
                                                                     of  fry

                                               26         48  hr       LC50
       3.2      U.S. Bureau of Commercial
                Fisheries 1967; Lowe et al .
                1970

       0.62     Goodman et al . 1985a
                U.S. Bureau of Commercial
                Fisheries 1965
*    Percent purity  Is given  In parentheses  when  available.

**   If the concentrations were not measured  and  the  published  results  were  not  reported  to  be  adjusted  for  purity,  the
     published results were multiplied by the purity  If  It was  reported  to be  less than 97|.

***  The test material was dissolved  from an  encapsulated  form  of  chlorpyr Hos.

••«* Aqed 11 weeks.

-------
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Jones, G.E., D.F. Carroll and W. Wills. 1976. Susceptibility of




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Nelson, J.H., N.E. Pennington and M.V. Meisch. 197bb. Use of a controlled




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                                    56

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Roberts, R.H., W.B. Kottkamp and M.V. Meisch. 1984. Larvici.de evaluations




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                                     58

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