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The results of this screening-level assessment on the proposed alpha-cypermethrin uses indicate 

that risks of adverse effects to non-target organisms are expected for aquatic animals and 

mammals. Indirect effects cannot be precluded for any taxa. These results are summarized in the 

body of the document in Section 1.2. 

Uncertainties

The environmental fate database was bridged from the cypermethrins to alpha-cypermethrin. 

Data specific for alpha-cypermethrin suggest that the persistence of alpha enriched mixture may 

be less persistent than that of the cypermethrins (zeta and racemic cypermethrin), therefore 

environmental exposures may be over estimated than if data were used that were conducted 

using alpha-cypermethrin as the test material. Appendix A outlines specific data that were 

conducted using alpha-cypermethrin as the test material and where data were bridged from the 

racemic or zeta-cypermethrin.

Additionally, there are no chronic exposure toxicity data for freshwater invertebrates, benthic 

organisms, or estuarine/marine fish. Therefore, acute-to-chronic ratios (ACRs) based on the 

appropriate relationships were applied to each of the taxa (e.g., an ACR based on 

estuarine/marine invertebrates, for which there are both acute and chronic toxicity data, was 

applied to freshwater invertebrates). The ACR is considered protective for the purpose of this 

risk assessment; however, the application of an ACR in the absence of actual data does introduce 

uncertainty to the risk assessment.

Recommended Label Amendment

The proposed label contains the following language: “DO NOT apply more than the combined 

maximum seasonal total for cypermethrin (including alpha-cypermethrin, zeta-cypermethrin, and 

any other products containing cypermethrin) products.” The phrase “combined maximum 

seasonal total for cypermethrin” is ambiguous and unclear. This is likely confusing for the end 

user who is applying a single product with a single active ingredient. EFED recommends 

revising the proposed label to reflect the permitted maximum annual mass of active ingredient, 

including mixtures with racemic and zeta-cypermethrin. This should be reflected on all 

cypermethrin labels.
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Environmental Fate and Ecological Risk Assessment 

for the Registration of Alpha-Cypermethrin

Alpha-Cypermethrin

(R)-cyano(3-phenoxyphenyl)methyl (1S,3S)-rel-3-(2,2-dichloroethenyl)-2,2-

dimethylcyclopropanecarboxylate

CAS Registry Number: 67375-30-8

PC Code: 209600

Prepared by:

Reuben D. Baris, Environmental Scientist

Elizabeth A. Riley, Biologist

U. S. Environmental Protection Agency

Office of Pesticide Programs

Environmental Fate and Effects Division

Environmental Risk Branch IV

1200 Pennsylvania Ave., NW

Mail Code 7507P

Washington DC 20460

Reviewed by:

Nathan Miller, Biologist, ERB VI

William P. Eckel, Ph.D, Senior Science Advisor, ERB VI

Mark Corbin, Branch Chief, ERB VI

Date: September 19, 2012

Table of Contents
-Page 4 of 126-

1. Executive Summary.............................................................................................................. 6

1.1. Nature of Chemical Stressor....................................................................................................................6

1.2. Potential Risks to Non-target Organisms...............................................................................................7

1.3. Conclusions - Exposure Characterization ..............................................................................................7

1.4. Conclusions - Effects Characterization...................................................................................................8

2. Problem Formulation ........................................................................................................... 9

2.1. Nature of Regulatory Action....................................................................................................................9

2.2. Stressor Source and Distribution ............................................................................................................9

2.2.1. Nature of Chemical Stressor................................................................................................................9

2.2.2. Overview of Pesticide Usage.............................................................................................................10

2.3. Receptors.................................................................................................................................................12

2.3.1. Aquatic and Terrestrial Effects..........................................................................................................12

2.3.2. Ecosystems Potentially at Risk..........................................................................................................13

2.4. Assessment Endpoints............................................................................................................................13

2.5. Conceptual Model ...................................................................................................................................14

2.5.1. Risk Hypotheses................................................................................................................................14

2.5.2. Conceptual Diagram..........................................................................................................................14

2.6. Analysis Plan ...........................................................................................................................................17

2.6.1. Residues of Concern..........................................................................................................................17

2.6.2. Preliminary Identification of Data Gaps and Uncertainties...............................................................18

2.6.3. Evaluation of Multiple Active Ingredients and Mixtures..................................................................18

2.6.4. Measures of Exposure .......................................................................................................................18

2.6.5. Measures of Effect.............................................................................................................................19

2.6.6. Integration of Exposure and Effects..................................................................................................20

3. Analysis............................................................................................................................. 21

3.1. Use Characterization..............................................................................................................................21

3.2. Exposure Characterization....................................................................................................................22

3.2.1. Environmental Fate and Transport Characterization .........................................................................22

3.2.2. Measures of Aquatic Exposure..........................................................................................................28

3.2.3. Measures of Terrestrial Exposure......................................................................................................33

3.3. Ecological Effects Characterization......................................................................................................37

3.3.1. Aquatic Toxicity Assessment ............................................................................................................37

3.3.2 Terrestrial Effects Characterization...................................................................................................44

4. Risk Characterization......................................................................................................... 47

4.1. Risk Estimation.......................................................................................................................................47

4.1.1. Aquatic Organisms............................................................................................................................48

4.1.2. Terrestrial Organisms........................................................................................................................51

4.2. Risk Description......................................................................................................................................54

4.2.1 Exposure to Aquatic Organisms........................................................................................................54

4.2.2 Risks to Aquatic Animals..................................................................................................................55

4.2.3 Risks to Aquatic Plants......................................................................................................................58

4.2.4. Risks to Mammals.............................................................................................................................59

4.2.5. Risk to Birds......................................................................................................................................59

4.2.6. Potential Effects on Terrestrial Invertebrates....................................................................................59

4.2.7. Risk to Terrestrial Non-target Plants.................................................................................................60

4.3. Uncertainties and Data Gaps.................................................................................................................61

4.3.1. Fate and Transport Uncertanties........................................................................................................61

4.3.2. Effects Uncertainties .........................................................................................................................61

5. Federally Threatened and Endangered (Listed) Species Concerns............................... 62

5.1. Action Area .............................................................................................................................................63

5.2. Taxonomic Groups Potentially at Risk.................................................................................................63

5.2.1. Probit Dose-Response Analysis ......................................................................................................65

5.2.2. Listed Species Occurrence Associated with Alpha-Cypermethrin Use ......................................66
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6. References............................................................................................................................ 68

6.1. Submitted Environmental Fate and Transport Studies.....................................................................69

6.2. Submitted Ecotoxicity Studies..............................................................................................................72

Appendix A. Alpha-Cypermethrin Bridging Strategy ..........................................................................94

Appendix B. Sumary of Environmental Fate Data for Alpha-cypermethrin....................................101

Appendix C. Aquatic Model Input/Output Data. ...............................................................................104

Appendix D. Model Outputs..................................................................................................................107

Appendix E. Reported Ecological Incidents for Racemic and Zeta-Cypermethrin in EIIS. ...........116

Appendix F. Federally Listed Species Potentially at Risk from the Proposed Uses of Alpha 

Cypermethrin..........................................................................................................................................125
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1. Executive Summary

1.1. Nature of Chemical Stressor

BASF is seeking registration for the new chemical insecticide alpha-cypermethrin (BAS 310 40 

I; (R)-cyano(3-phenoxyphenyl)methyl (1S,3S)-rel-3-(2,2-dichloroethenyl)-2,2-

dimethylcyclopropanecarboxylate; CAS#: 67375-30-8; PC code: 209600). Alpha-cypermthrin is 

a broad-spectrum Type II pyrethroid insecticide that is proposed for use on a wide variety of 

agricultural crops. Alpha-cypermethrin, like other pyrethroids, is considered an axonic poison 

that prevents sodium channels in an organism’s neuronal membranes from closing, resulting in 

paralysis. 

Alpha-cypermethrin is an enriched enantiomeric mixture of the previously registered racemic 

cypermethrin (PC code 109702). Racemic cypermethrin consists of eight stereoisomers with two 

optically active centers (stereogenic centers or stereocenters) while the enriched alphacypermethrin consists of only 2 of the stereoisomers. In addition to the registerd racemic and 

proposed new chemical alpha-cypermethrin, the Agency has previously registered the 

isomerically enriched zeta-cypermethrin (PC code 129064), which consists of 4 of the 

stereoisomers. Based on similarities in the chemical properties and toxicological endpoints, 

environmental fate and ecotoxicity data are bridged between racemic cypermethrin and the 

enriched isomeric mixtures (i.e., alpha-cypmerthin and zeta-cypermethrin) (Appendix A

includes additional detail on the bridging strategy). Though the environmental fate and 

ecotoxicity datasets for alpha-cypermethrin mostly consist of studies conducted with either 

racemic or zeta cypermethrin, this document will discuss the environmental fate and ecological 

risks associated with the proposed new chemical alpha-cypermethrin and reference the other 

chemicals where appropriate. 

This assessment is for a national registration request for the following uses: alfalfa, brassica 

vegetables, citrus fruits, corn (field, pop, seed and sweet), cotton, cucurbits, fruiting vegetables, 

leafy vegetables, legume vegetables, rice (grain and straw), root and tuber vegetables, sorghum 

(and other cereals), soybeans, sugar beets, tree nuts, and wheat. Maximum application rates 

range from 0.075 to 0.20 lbs a.i./A/yr. This assessment is based on proposed maximum 

application rates for all uses. 

One end-use formulation of alpha-cypermethrin is proposed for registration in the United States. 

The proposed label includes a statement that alpha-cypermethrin may be mixed with other 

products approved for use on the proposed crops, including racemic and zeta-cypermethrin. This 

risk assessment applies to the proposed end-use formulation of alpha-cypermethrin only and is 

not applicable if the formulation is used in conjunction with the other cypermethrins. 

Major transformation products resulting from the environmental degradation of alphacypermethrin are 3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropane carboxylic acid (DCVA) 

and 3-phenoxybenzaldehyde, which degrades further to 3-phenoxybenzoic acid (3-PBA). Based 

on the assumption that cleavage of the ester bond in the parent compound results in biologically 

inactive degradates, these compounds are not expected to pose greater toxicity to non-target 
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organisms; therefore only the parent compound was considered for toxicological concern for 

both aquatic and terrestrial ecosystems. This assumption is supported by the results of acute 

toxicity studies in freshwater fish and invertebrates which indicate that the alpha-cypermethrin 

degradate 3-PBA acid is much less toxic than the parent compound. 

1.2. Potential Risks to Non-target Organisms

The results of this screening-level assessment on the proposed alpha-cypermethrin uses indicate 

that risks of adverse effects to non-target organisms are expected for aquatic animals and 

mammals. Indirect effects cannot be precluded for any taxa. 

Table 1.1. Potential Effects to Federally Listed Taxa Associated with Direct or Indirect 

Effects from the Proposed New Uses of Alpha-Cypermethrin.

Listed Taxon Direct Effects Indirect Effectsa

Terrestrial and semi-aquatic plants - monocots No Yes

Terrestrial and semi-aquatic plants - dicots No Yes

Birds No Yes

Terrestrial-phase amphibians and reptiles No Yes

Mammals Yes Yes

Aquatic nonvascular plants No Yes

Aquatic vascular plants No Yes

Freshwater fish Yes Yes

Aquatic-phase amphibians Yes Yes

Freshwater crustaceans Yes Yes

Mollusks Yes Yes

Marine/estuarine fish Yes Yes

Marine/estuarine invertebrates Yes Yes a

until an endangered species assessment is complete, indirect effects to all species cannot be precluded

1.3. Conclusions - Exposure Characterization 

Alpha-cypermethrin is slightly to moderately persistent in environmental conditions based on

Goring et al. (1975), and is considered immobile, lipophilic, and nonvolatile. Alphacypermethrin is moderately persistent in soil, with half-lives ranging from 28 to 61 days in 

aerobic soil and 53 to 63 days in anaerobic soil. There is no evidence of degradation via 

hydrolysis, which was studied across environmental pHs. Laboratory data show that alphacypermethrin degraded by aerobic aquatic metabolism with half-lives ranging from 9 to 10 days. 

A potentially major route of degradation in shallow, clear waters (e.g., applications to flooded 

rice paddies) may be aqueous photolysis (environmental half-life of 36 days). Alphacypermethrin has the potential to bioconcentrate in aquatic food webs..

Aquatic exposure estimates are based on the exposure of the parent compound alphacypermethrin only. Major transformation products were reported to be less toxic than the parent 

(see discussion above in Section 1.1).Therefore, conservative aquatic exposure estimates were 

generated using environmental half-lives for the parent only. 
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Aquatic exposure was estimated for all uses of alpha-cypermethrin. Modeling runs were 

combined into common crop-use categories (e.g., brassica vegetables). These uses result in the 

maximum exposure for each type of application method. Therefore, they provide conservative 

estimates of exposure for other proposed uses with lower application rates and similar 

application methods that were not specifically modeled. The range of all proposed uses are listed 

in Table 3.1. Aquatic exposure estimates are presented in Tables 3.8-3.10.

Terrestrial exposure estimates are based on the residue levels of alpha-cypermethrin on short 

grass, tall grass, broadleaf plants, small insects, fruits, pods, seeds, and large insects for all 

proposed uses of alpha-cypermethrin. Terrestrial exposure estimates are presented in Tables 

3.11-3.13.

1.4. Conclusions - Effects Characterization 

For spray applications of alpha-cypermethrin, there is acute risk to all (water column-dwelling 

and sediment-dwelling) aquatic invertebrates and fish, and chronic risk to all (water columndwelling and sediment-dwelling) aquatic invertebrates in the water column. Although this 

compound binds readily to particulate and organic carbon in the water column (average Koc = 

141,700 L/Kg), possibly limiting bioavailability in this media after 24 to 48 hours, the bound 

residues settle onto the benthos, increasing alpha-cypermethrin concentrations in the sediment. 

Alpha-cypermethrin is expected to be relatively stable to breakdown from sunlight (aqueous 

photolysis half-life of approximately 36 days and a dark control corrected soil photolysis halflife of over 100 days) and biodegrade slowly with a half-life of about 2 months in aerobic and 

anaerobic soils. Therefore the sediment compartment may serve as a repository of pesticide 

residues that can result in a direct acute and chronic toxic risk concern for benthic and epibenthic 

aquatic organisms (e.g. early life stage of many invertebrates and fish, as well as crabs and 

shrimp) and a potential indirect risk to fish through food chain alterations that can affect 

freshwater and estuarine fish.

Acute and chronic risk to avian species is not expected for spray applications of alphacypermethrin. However, exposure of mammals to alpha-cypermethrin spray applications is 

expected to result in acute risk to listed species, and chronic risk to listed and non-listed species.

A qualitative analysis of the available information indicates there may be potential for risk to 

listed and non-listed terrestrial invertebrates, such as honey bees and earthworms.

Tier II studies of the effect of the alpha-cypermethrin TGAI on vegetative vigor in terrestrial 

plants were submitted. The results indicated that effects on terrestrial plants are possible at 

application rates less than the maximum per acre application rate for the proposed uses of alphacypermethrin. However, due to uncertainties associated with the study this data is not appropriate 

for use in risk assessment. This is identified as a data gap.
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2. Problem Formulation

The purpose of problem formulation is to provide the foundation for the environmental fate and 

ecological risk assessment for the registration of the new chemical alpha-cypermethrin, (BAS 

310 40 I; (R)-cyano(3-phenoxyphenyl)methyl (1S,3S)-rel-3-(2,2-dichloroethenyl)-2,2-

dimethylcyclopropanecarboxylate; CAS#: 67375-30-8; PC code: 209600). The problem 

formulation sets the objectives for the risk assessment, establishes a risk hypothesis and 

conceptual model depicting potential risk, and provides a plan for analyzing the data and 

characterizing the risk associated with the proposed use of alpha-cypermethrin (USEPA, 1998). 

2.1. Nature of Regulatory Action

The U.S. Environmental Protection Agency (EPA or the Agency) is required under the Federal 

Insecticide, Fungicide, and Rodenticide Act (FIFRA) to ensure that the newly proposed use of

alpha-cypermethrin as an insecticide does not have the potential to cause unreasonable adverse 

effects to the environment. In addition to non-target animals and plants, potential effects to 

listed species (i.e., species on the Federal list of endangered and threatened wildlife and plants)

and their designated critical habitat are also considered under the Endangered Species Act (ESA) 

in order to ensure that the registration of alpha-cypermethrin is not likely to jeopardize the 

continued existence of listed species or adversely modify their critical habitat. In order to meet 

the requirements of FIFRA and the ESA, this assessment follows EPA guidance on conducting 

ecological risk assessments (USEPA, 1998) and Office of Pesticide Program’s Overview 

Document, which contains guidance for assessing pesticide risks to non-target and listed 

organisms (USEPA, 2004).

The end result of the EPA pesticide registration process (i.e., the FIFRA regulatory action) is an 

approved (or disapproved) product label. The label is a legal document that stipulates how and 

where a given pesticide may be used. Product labels (also known as end-use labels) describe the 

formulation type (e.g., liquid or granular), acceptable methods of application, approved use sites, 

and any restrictions on how applications may be conducted. Therefore, the use, or potential use, 

described by the pesticide’s labels is considered “the action” being assessed. This assessment 

was prepared to support evaluation of the proposed new chemical registration of alphacypermethrin.

2.2. Stressor Source and Distribution

2.2.1. Nature of Chemical Stressor

BASF is seeking registration for the use of the new chemical insecticide alpha-cypermethrin

(BAS 310 40 I), R)-cyano(3-phenoxyphenyl)methyl (1S,3S)-rel-3-(2,2-dichloroethenyl)-2,2-

dimethylcyclopropanecarboxylate. According to BASF, alpha-cypermethrin is a Type II 

synthetic pyrethroid. The pyrethroids (including alpha-cypermethrin) share similar modes of 

action, and are considered axonic poisons that affect both the peripheral and central nervous 

system. It is now well established that severe neurological symptoms of poisoning with 
-Page 10 of 126-

pyrethroids in mammals and insects are the result of modification of sodium (Na+) channel 

activity (cellular pores through which sodium ions are permitted to enter the axon to cause 

excitation) (Matsumura 1985). Advanced electrophysiological experiments using a voltage 

clamp and a patch clamp, together with ligand-binding and ionic flux experiments, have unveiled 

unique actions of pyrethroids that keep the Na+ channel in the open state for an extremely long 

period, sometimes as long as several seconds. This modification of Na+ channel properties leads 

to hyperactivity of the nervous system. This action leads to spontaneous depolarizations, 

augmented neurotransmitter secretion rate and neuromuscular block, which ultimately results in 

paralysis of the insect. Pyrethroids have also been shown to suppress gamma-aminobutyric acid 

(GABA) and glutamate receptor-channel complexes and voltage-activated calcium (Ca 2+) 

channels, but the toxicological significance of these actions is uncertain. 

Relative to physiological responses, researchers have designated two types of pyrethroids, Type I 

(e.g., pyrethrins, S-bioallethrin, resmethrin, permethrin) and Type II (e.g., the cypermethrins, 

deltamethrin, fenvalerate). Alpha-cypermethrin is classified as Type II synthetic pyrethroid, with 

a cyano group at the α-carbon position of the alcohol moiety, and is considered a third generation 

pyrethroid, that is, more light-stable and persistent in the environment than early pyrethroids like 

allethrin, phenothrin (also commonly known as sumithrin) and resmethrin. Alpha-cypermethrin

has two optically active centers and is composed of 2 isomers, and like all pyrethroids, is a 

contact poison that can quickly penetrate the nervous system and have an effective “knockdown” 

action (induction of temporary paralysis) for most flying insects. 

Alpha-cypermethrin is formulated as an emulsifiable concentrate (BAS 310 40 I EC®) It is 

applied to alfalfa, brassica vegetables, citrus fruits, corn (field, pop, seed and sweet), cotton, 

cucurbits, fruiting vegetables, leafy vegetables, legume vegetables, rice (grain and straw), root 

and tuber vegetables, sorghum (and other cereals), soybeans, sugar beets, tree nuts, and wheat.

The proposed maximum annual application rates are on citrus fruits. Citrus fruits may be treated 

with a single maximum application rate of 0.025 lbs a.i./A with a 14-day reapplication interval 

for a total seasonal mass applied of 0.20 lbs/A (i.e., 8 applications). Other crop treatments are 

proposed at lower seasonal rates as discussed in Section 3.1. 

2.2.2. Overview of Pesticide Usage

Usage data are not available for alpha-cypermethrin because it is a new active ingredient 

proposed for use in the United States.

Alpha-cypermethrin is proposed as a Restricted Use Pesticide (RUP) for agricultural uses 

because of its acute toxicity to aquatic organisms. For agricultural products, application methods 

include aerial, air blast, ground spray, or chemigation. The following labeling statements appear 

on the proposed label to avoid spray drift and contamination of aquatic environments, and were 

used to refine the surface water exposure assessment (described in Section 3.2.2.1) where 

appropriate:

BUFFER ZONE REQUIREMENTS for AGRICULTURAL CROPS
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• Vegetative Buffer Strip: 

o Construct and maintain a minimum 10-foot-wide vegetative filter strip of grass or

other permanent vegetation between the field edge and down gradient aquatic 

habitat (such as, but not limited to, lakes; reservoirs; rivers; permanent streams; 

marshes or natural ponds; estuaries; and commercial fish farm ponds).

o Only apply products containing alpha-cypermethrin onto fields where a 

maintained vegetative buffer strip of at least 10 feet exists between the field and 

down gradient aquatic habitat.

• Buffer Zone for Ground Application (groundboom, overhead chemigation, or

airblast):

o Do not apply within 25 feet of aquatic habitats (such as but not limited to, lakes, 

reservoirs, rivers, streams, marshes, ponds, estuaries, and commercial fish ponds).

• Buffer Zone for ULV Aerial Application:

o Do not apply within 450 feet of aquatic habitats (such as but not limited to, lakes, 

reservoirs, rivers, streams, marshes, ponds, estuaries, and commercial fish ponds).

• Buffer Zone for Non-ULV Aerial Application:

o Do not apply within 150 feet of aquatic habitats (such as but not limited to, lakes, 

reservoirs, rivers, streams, marshes, ponds, estuaries, and commercial fish ponds).

SPRAY DRIFT MANAGEMENT for AGRICULTURAL CROPS

• Wind Direction and Speed:

o Only apply this product if the wind direction favors on-target deposition.

o Do not apply when the wind velocity exceeds 15 mph.

• Temperature Inversion

o Do not make aerial or ground applications into temperature inversions.

o Inversions are characterized by stable air and increasing temperatures with height 

above the ground. Mist or fog may indicate the presence of an inversion in humid 

areas. The applicator may detect the presence of an inversion by producing smoke 

and observing a smoke layer near the ground surface.

• Droplet Size:

o Use only Medium or coarser spray nozzles (for ground and non-ULV aerial 

application) according to ASAE (S572) definition for standard nozzles. In 

conditions of low humidity and high temperatures, applicators should use a 

coarser droplet size. 

• Additional Requirements for Ground Applications:

o Wind speed must be measured adjacent to the application site on the upwind side, 

immediately prior to application.

o For ground boom applications, apply using a nozzle height of no more than 4 feet 

above the ground or crop canopy.

o For airblast applications, turn off outward pointing nozzles at row ends and when 

spraying the outer two rows. To minimize spray loss over the top in orchard 

applications, spray must be directed into the canopy.

• Additional Requirements for Aerial Applications:
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o The spray boom should be mounted on the aircraft as to minimize drift caused by 

wingtip or rotor vortices. The minimum practical boom length should be used and 

must not exceed 75% of the wing span or 80% rotor diameter.

o Flight speed and nozzle orientation must be considered in determining droplet 

size.

o Spray must be released at the lowest height consistent with pest control and flight 

safety. Do not release spray at a height greater than 10 feet above the crop canopy 

unless a greater height is required for aircraft safety.

o When applications are made with a cross-wind, the swath will be displaced 

downwind. The applicator must compensate for this displacement at the 

downwind edge of the application area by adjusting the path of the aircraft 

upwind.

Alpha-cypermethrin is toxic to fish, aquatic invertebrates and beneficial insects. The following 

Environmental Hazards statements appear on the proposed label:

ENVIRONMENTAL HAZARD STATEMENTS 

• This pesticide is extremely toxic to fish, aquatic invertebrates, oysters and shrimp. Do not 

apply directly to water, or to areas where surface water is present or to intertidal areas 

below the mean water mark. Do not apply when weather conditions favor drift from 

treated areas. Drift and runoff from treated areas may be hazardous to aquatic organisms 

in neighboring areas. Do not contaminate water when disposing of equipment wash 

waters. 

• This product is highly toxic to bees exposed to direct treatment on blooming crops or 

weeds. Do not apply this product or allow it to drift to blooming crops or weeds while 

bees are actively visiting the treatment area.

In addition, the proposed label contains the following language: “DO NOT apply more than the 

combined maximum seasonal total for cypermethrin (including alpha-cypermethrin, zetacypermethrin, and any other products containing cypermethrin) products.” It is unclear what the 

“combined maximum seasonal total” is for cypermethrin and the interpretation is vague which is

confusing for the end user. 

2.3. Receptors

2.3.1. Aquatic and Terrestrial Effects

In ecological risk assessment, a receptor is a biological entity that is exposed to a stressor 

(USEPA, 1998). Consistent with the process described in the Overview Document (USEPA, 

2004), this risk assessment uses a surrogate species approach in its evaluation of alphacypermethrin. Toxicity data generated using surrogate test species, which are intended to be 

representative of broad taxonomic groups, are used to infer potential effects on a variety of 

species (receptors) included under these broader taxonomic groupings. Table 2.1 provides the 

general taxonomic groups and surrogate species tested to evaluate potential ecological effects of 
-Page 13 of 126-

alpha-cypermethrin to broad classes of non-target organisms. Within each of these taxonomic 

groups, a measure of effect is selected from among the available test data. 

Table 2.1. Taxonomic Groups and Test Species Evaluated for Assessing Potential 

Ecological Effects of Alpha-cypermethrin.

Taxonomic Group Typical Species

Birds1 Mallard duck (Anas platyrhynchos)

Bobwhite quail (Colinus virginianus)

Mammals Norway rat (Ratus norvegicus)

Invertebrates Honey bee (Apis mellifera L.)

Freshwater fish2 Bluegill sunfish (Lepomis macrochirus)

Rainbow trout (Oncorhynchus mykiss)

Fathead minnow (Pimephales promelas)

Freshwater invertebrates Water flea (Daphnia magna)

Midge (Chironomus riparius)

Estuarine/marine fish Sheepshead minnow (Cyprinodon variegatus)

Estuarine/marine invertebrates Mysid (Americamysis bahia)

Eastern oyster (Crassostrea virginica)

Terrestrial plants3 Monocots – Crop species, such as corn (Zea mays)

Dicots – Crop Species, such as soybean (Glycine max)

Aquatic plants and algae4 Duckweed (Lemna gibba) 

Freshwater Algae (Pseudokirchneriella subcapitata) 1 Birds represent surrogates for terrestrial-phase amphibians and reptiles. 2 Freshwater fish may be surrogates for aquatic-phase amphibians. 3 Four species of two families of monocots, of which one is corn; six species of at least four dicot families, of which one is soybeans. 4 Four species of non-vascular algae including a freshwater green algae, a cyanobacterium, a marine diatom, and a freshwater diatom. 

2.3.2. Ecosystems Potentially at Risk 

The ecosystems potentially at risk are often extensive in scope; therefore, it may not be possible 

to identify specific ecosystems during the development of a nation-wide ecological risk 

assessment. However, in general terms, terrestrial ecosystems potentially at risk could include 

the treated field and immediately adjacent areas that may receive drift or runoff. Areas adjacent 

to the treated field could include cultivated fields, fencerows and hedgerows, meadows, fallow 

fields or grasslands, woodlands, riparian habitats, and other uncultivated areas. Current label 

directions for alpha-cypermethrin require vegetative buffer strips and impose limitations to 

reduce the potential for spray drift to impact areas adjacent to the treated field. However, due to 

the potential persistence of alpha-cypermethrin under certain circumstances, it is expected to 

drift and/ or runoff from application to food crops, resulting in possible exposure to aquatic 

ecosystems. Aquatic ecosystems potentially at risk include water bodies adjacent to or 

downstream from use sites, and might include impounded bodies such as ponds, lakes and 

reservoirs, or flowing waterways such as streams or rivers including all adjacent off-channel 

habitats that are permanently or intermittently connected to flowing waters. For uses in coastal 

areas, aquatic habitat also includes marine ecosystems, including estuaries, embayments, and 

near-shore environments such as tidal marshes.

2.4. Assessment Endpoints
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Assessment endpoints represent the actual environmental value that is to be protected, defined by 

an ecological entity (species, community, or other entity) and its attribute or characteristics 

(USEPA, 1998). For alpha-cypermethrin, ecological entities of potential concern include the 

following: birds, amphibians, reptiles, mammals, freshwater fish and invertebrates, 

estuarine/marine fish and invertebrates, terrestrial plants, non-target terrestrial invertebrates, and 

aquatic vascular and non-vascular plants. The attributes for each of these entities may include 

growth, survival, and reproduction (Table 2.2 in Section 2.6.4).

2.5. Conceptual Model

For a pesticide to pose an ecological risk, it must reach ecological receptors in biologically 

significant concentrations. An exposure pathway is the means by which a pesticide moves in the 

environment from a source to an ecological receptor. For an ecological pathway to be complete, 

it must have a source, a release mechanism, an environmental transport mechanism, and a 

feasible route of exposure.

The conceptual model is intended to provide a written description and visual representation of 

anticipated relationships between alpha-cypermethrin, potential routes of exposure, and the 

predicted effects for the assessment endpoints. The conceptual model consists of two major 

components: risk hypotheses and a conceptual diagram (USEPA, 1998).

2.5.1. Risk Hypotheses

For alpha-cypermethrin, the following generic ecological risk hypothesis is being employed for 

this screening-level risk assessment:

Alpha-cypermethrin, when used outdoors in accordance with registered labels, have the 

potential to lead to off-site movement of the compound via agricultural,, spray drift, and 

eroded soil leading to exposure of nontarget plants and animals. 

Based on information on the environmental fate, mode of action, direct toxicity and 

potential indirect effects, EFED assumes that the proposed uses of alpha-cypermethrin

have the potential to cause reduced survival, growth, and reproduction to non-target 

terrestrial and/ or aquatic animals and plants.

2.5.2. Conceptual Diagram

The conceptual model is a graphical representation of predicted relationships between ecological 

receptors, both listed (threatened and endangered) and non-listed, and the stressors to which they 

may be exposed. A conceptual model specifies potential routes of exposure, biological receptor 

types, and effects endpoints of potential concern. The conceptual model for terrestrial organisms 

exposed to alpha-cypermethrin is presented in Figures 2.1, while the conceptual model for 

aquatic organisms exposed to alpha-cypermethrin is presented in Figure 2.2.

Under the possible uses of alpha-cypermethrin, the sources and mechanisms of release of the 
-Page 15 of 126-

compounds are from ground or aerial spray, chemigation, or ULV applications. Surface runoff 

from the areas of application is assumed to depend on factors such as topography, irrigation, and 

rainfall events. Direct deposition may result in contamination of food items that may be 

consumed by terrestrial organisms. Spray drift results in contaminated adjacent areas, including 

bodies of water. Leaching to groundwater is not considered an important source because alphacypermethrin, like many other pyrethroids, shows low mobility in a variety of soils. Alphacypermethrin appears to have a low potential for volatilization, with a low vapor pressure and 

Henry’s Law Constants. The low vapor pressure (~10-9torr) and relatively low Henry’s Law 

constant (~10-7 atm/m3-mol), and its binding capacity, suggest that the potential for atmospheric 

transport for alpha-cypermethrin is relatively low and that this source of the chemical is of low 

importance, compared to spray drift, runoff and/ or direct contact after application.

The major point of exposure for aquatic receptors is through direct contact with the water 

column, sediment, and pore water (gill/ integument) contaminated with spray drift (from spray 

application) and/or runoff and flow (e.g., piped storm drains) from treated areas. Indirect effects 

to aquatic organisms (both fish and aquatic invertebrates) can also occur through impact to 

various food chains. The representative aquatic receptors are certain freshwater and estuarine/ 

marine fish, invertebrates, and, in certain cases, aquatic plants. For terrestrial receptors, the 

major point of exposure is consumption of food contaminated with residues such as grass, 

foliage, and small insects. For plants, the point of exposure is direct contact or root uptake. The 

representative terrestrial receptors are mammals, birds and terrestrial plants. The attribute 

changes used to assess risk to terrestrial receptors depend on the type of test (e.g., reduced 

survival, growth, or reproduction for animals and seedling emergence and vegetative vigor for 

plants). It should be noted, that these species do not cover all the possible species in the animal 

and plant kingdoms; certain taxa are considered as surrogates for other taxa. For example, fish 

are considered surrogates for aquatic phase amphibians.

This conceptual model also shows information about the potential for biomagnification for 

alpha-cypermethrin (see piscivorous birds and mammals in Fig. 2.2). The reported value of log 

octanol/ water partition coefficient of 6.4 suggests that alpha-cypermethrin has the potential to 

bioaccumulate in aquatic organisms assuming that chemical metabolism is negligible. Maximum 

BCFs for alpha-cypermethrin are 161x for edible tissue, 883x for viscera, and 448x for whole 

fish. Depuration appeared to be moderately slow, with ~10-15% of the initial residues remaining 

after 21 days. Thus, it appears that there is potential for bioaccumulation/ bioconcentration in 

aquatic organisms and biomagnification in terrestrial organisms. However, potential for 

bioaccumulation/bioconcentration may be tempered by the sensitivity of aquatic animals to alphcypermethrin.

Alpha-cypermethrin has a solubility of 4.0 ppb and a very high KOW. These properties suggest 

that the chemical could partition to the sediment and particulates suspended in bodies of water. 

Alpha-cypermethrin is likely to concentrate in the sediments, especially after repeated exposures 

(applications), where it will likely persist. Such sediments could serve as repositories of the 

chemicals for extended periods of time and could potentially be toxic to sediment dwelling 

organisms, affecting the food chain. These issues will also be assessed in the risk assessment.

 

 
-Page 16 of 126-

Figure 2.1. Conceptual model for alpha-cypermethrin effects on terrestrial organisms.

Stressor

Source

Attribute

Change

Alpha-cypermethrin applied to agricultural use sites

Direct

application Spray drift

Terrestrial 

vertebrates*

Terrestrial 

invertebrates

Individual 

organisms

Reduced survival

Reduced growth

Reduced reproduction

Food chain

Reduction in prey and food

Modification of PCEs 

 related to prey availability

Habitat integrity

Reduction in primary productivity

Reduced cover

Community change

Modification of PCEs related

 to habitat

Terrestrial plants

grasses/ forbs, fruit, seeds 

(trees, shrubs)

Runoff

Terrestrial 

vertebrates 

Exposure Media 

& Receptors Soil

Ingestion

Ingestion

Ingestion

Dermal uptake/Ingestion

Atmospheric 

transport

Root uptake/contact

Wet/dry deposition

Ingestion

Leaching to

Groundwater Irrigation 

water

* Drinking water and inhalation exposure pathways for terrestrial vertebrates are not expexted to be of concern.
-Page 17 of 126-

Figure 2.2. Conceptual model for alpha-cypermethrin effects on aquatic organisms.

2.6. Analysis Plan

2.6.1. Residues of Concern

Major transformation products resulting from the environmental degradation of alphacypermethrin are 3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropane carboxylic acid (DCVA) 

and 3-phenoxybenzaldehyde, which degrades further to 3-phenoxybenzoic acid (3-PBA). Based 

on the assumption that cleavage of the ester bond in the parent compound results in biologically 

inactive degradates, these compounds are not expected to pose greater toxicity to non-target 

organisms; therefore only the parent compounds were considered for toxicological concern for 

both aquatic and terrestrial ecosystems. This assumption is supported by the results of acute 

toxicity studies in freshwater fish and invertebrates which indicate that the alpha-cypermethrin 

degradate 3-PBA is much less toxic than the parent compound. 

Therefore, alpha-cypermethrin alone is the residue of concern in this assessment.

**Considered a minor route of exposure

Stressor

Source

Receptors

Attribute

Change

Alpha-cypermethrin applied to agricultural use sites

Spray drift

Aquatic animals

Invertebrates 

Vertebrates

Piscivorous mammals 

 and birds** 

Individual organisms

Reduced survival (2)

Reduced growth

Reduced reproduction

Food chain

Reduction in algae and 

 vascular plants

Reduction in prey

Modification of PCEs 

 related to prey availability

Habitat integrity

Reduction in primary 

 productivity

Reduced cover

Community change

Modification of PCEs related to 

 habitat

Surface water/

Sediment

Runoff

Aquatic Animals

Invertebrates

Vertebrates

Exposure

Media

Uptake/gills 

or integument

Ingestion Ingestion

Atmospheric 

transport

Wet/dry deposition

Soil Leaching to

Groundwater

Uptake/gills 

or integument

Aquatic Plants

Non-vascular

Vascular

Uptake/cell, 

roots, leaves Riparian plants

terrestrial 

exposure 

pathways; see 

Figure 6.1b

Flow 
-Page 18 of 126-

2.6.2. Preliminary Identification of Data Gaps and Uncertainties

For the purposes of risk assessment, the submitted environmental fate and ecotoxicity data for 

alpha-cypermethrin are inadequate for risk assessment. However, as discussed previously, data 

are bridged for the databases of the racemic (cypermethrin) and the previously registered 

enriched mixtures (zeta-cypermethrin). BASF submitted a bridging strategy for the use of 

environmental fate and ecotoxicity data for racemic and zeta-cypermethrin in the risk assessment 

for the new product, alpha-cypermethrin; the Agency found this strategy acceptable (Appendix 

A). Therefore the environmental fate and ecotoxicity database for alpha-cypermethrin is bridged 

across the isometric mixtures. A complete summary of the submitted environmental fate and 

ecotoxicity data is included in USEPA, 2002. Additional data submitted after 2007 are included 

in the environmental database for racemic and zeta-cypermethrin. Data submitted using alphacypermethrin as the test matrial are summarized in Appendix B.

2.6.3. Evaluation of Multiple Active Ingredients and Mixtures 

The Agency does not routinely include in its risk assessments an evaluation of mixtures of active 

ingredients, either those mixtures of multiple active ingredients in product formulations or those 

in the applicator’s tank. In the case of the product formulations of active ingredients (that is, a 

registered product containing more than one active ingredient), each active ingredient is subject 

to an individual risk assessment for regulatory decision regarding the active ingredient on a 

particular use site. If effects data are available for a formulated product containing more than 

one active ingredient, they may be used qualitatively or quantitatively in accordance with the 

Agency’s Overview Document and the Services’ Evaluation Memorandum (U.S. EPA 2004; 

U.S. FWS/NMFS 2004). However, the proposed end-use product for the new chemical alphacypermethrin is as a single active ingredient formulation. 

2.6.4. Measures of Exposure

Measures of exposure are based on aquatic and terrestrial models that estimate environmental 

concentrations of alpha-cypermethrin using labeled application rates and methods. For aquatic 

exposure the Tier II model Pesticide Root Zone Model (PRZM v3.12.2; May 12, 2005) linked 

with EXposure Analysis Modeling System (EXAMS v2.98.4.6; Apr. 25, 2005) via the 

PRZM/EXAMS model shell (PE v5.0, Nov. 15, 2006), i.e., PRZM/EXAMS) and the Tier I Rice 

Model (v1.0, May 8, 2007) were used to estimate screening-level exposure concentrations in 

aquatic environments. The measure of exposure for aquatic species in surface water bodies 

receiving runoff and/or spray drift is a return frequency of 1-in-10 years of the estimated 

environmental concentrations (EEC), based on 30-year simulations. The maximum 1-in-10 year 

return frequency concentration is used for estimating acute exposures to aquatic organisms 

(plants and animals); the 1-in-10 year 21-day mean concentration is used for assessing aquatic 

invertebrate chronic exposure; and the 1-in-10 year 60-day mean concentration is used for 

assessing chronic exposure for fish (and aquatic-phase amphibians for which fish serve as 

surrogates). Exposure to benthic organisms from sediment concentrations in water bodies was 

assessed; pore-water 1-in-10 year EECs were calculated for maximum use patterns. 

Terrestrial exposure estimates for avian and mammalian risk assessments were derived using the 
-Page 19 of 126-

T-REX model (version 1.4.1, 10/08/2008). The assumption of the model is that mammals and 

birds may be exposed via their consumption of treated seeds on or immediately adjacent to the 

site of application. 

The Screening Imbibition Program (SIP v.1.0) and Screening Tool for Inhalation Risk (STIR 

v.1.0) were used to calculate upper bound estimates of wildlife exposure via drinking water and 

inhalation, respectively, using alpha-cypermethrin’s solubility or vapor pressure, avian and 

mammalian toxicity endpoints.

The KABAM (Kow-based bioaccumulation) model version 1.0 (documented at 

http://www.epa.gov/oppefed1/models/water/kabam/kabam_user_guide.html) was used to 

estimate potential bioaccumulation of hydrophobic organic pesticides in freshwater aquatic 

ecostystems and risks to mammals and birds consuming aquatic organisms which have 

bioaccumulated these pesticides. 

2.6.5. Measures of Effect 

Measures of effect are obtained from a suite of registrant-submitted guideline studies that were 

conducted with a limited number of surrogate test species (Table 2.1). No additional ecotoxicity 

data on alpha-cypermethrin were located, based on an August 2011 query of the open literature 

in the publically available version of the ECOTOX database (http://cfpub.epa.gov/ecotox/).

The acute measures of effect used in this baseline assessment are the LD50 (median Lethal Dose), 

LC50 (median Lethal Concentration) or EC50 (median Effects Concentration). These are 

measures of acute toxicity which result in 50% of the respective effect in tested organisms. The 

endpoints for chronic measures of exposure are the no observed adverse effect concentration 

(NOAEC) and the no observed adverse effect level (NOAEL). Toxicity studies were submitted 

for freshwater fish and invertebrates, estuarine/marine fish and invertebrates, aquatic plants, 

birds, mammals, bees, and other terrestrial invertebrates. The endpoints used for risk 

characterization are derived from studies which underwent review and were classified as 

“acceptable” (conducted under guideline conditions and considered to be scientifically valid) or 

“supplemental” (conditions deviated from guidelines but the results are considered to be 

scientifically valid). 

Table 2.2 lists the measures of environmental exposure and ecological effects used to assess the 

potential risks of alpha-cypermethrin to non-target organisms. The methods used to assess the 

risk are consistent with those outlined in the document “Overview of the Ecological Risk 

Assessment Process in the Office of Pesticide Programs” (USEPA, 2004).
-Page 20 of 126-

Table 2.2. Measures of Exposure and Measures of Effect Used in Assessing Potential Risks 

Associated with the Proposed Uses of Alpha-Cypermethrin.

Assessment Endpoint Surrogate Species and Measures of 

Ecological Effect1 Measures of Exposure

Birds2

Survival

Lowest acute LD50 (single oral dose test) 

and LC50 (subacute dietary test)

Upper-bound residues on 

food items

Reproduction 

and Growth

Lowest NOAEC

(21-week reproduction test)

Mammals

Survival Lowest acute LD50 (single oral dose test)

Reproduction 

and Growth

Lowest NOAEC 

(2-generation reproduction test)

Aquatic Animals (Fish and 

invertebrates)3

Survival Lowest tested LC50 or EC50

(acute toxicity test)

Peak EECs

4

Reproduction 

and Growth

Lowest NOAEC (early life-stage or full 

life-cycle tests)

21-day EECs for invertebrates 

and 60-day EECs for fish4

Terrestrial plants5 Survival and 

growth

Lowest EC25 (for non-listed plants) and 

corresponding NOAEC (for listed 

plants)

(endpoints derived for monocots and 

dicots from seedling emergence and 

vegetative vigor studies)

Estimates of runoff and spray 

drift to non-target areas

Insects6 Survival (not 

quantitatively 

assessed)

Lowest honeybee LD50 (acute contact 

test)

Lowest Earthworm LC50

Maximum application rate for 

honeybees and estimates of 

soil concentrations for 

earthworms

Aquatic plants (vascular 

and non-vascular)

Survival and 

growth

Lowest EC50 (for non-listed plants) and 

corresponding NOAEC or EC05 (for 

listed plants)

Peak EECs

4

1 The most sensitive species tested within taxonomic groups is used for screening-level risk assessments. 2 Birds represent surrogates for terrestrial-phase amphibians and reptiles. 3 Freshwater fish represent surrogates for aquatic-phase amphibians. 4 Aquatic EECs are based on modeling described in Section 3.2.2.1. 5 Four species of two families of monocots - one is corn, six species of at least four dicot families, of which one is soybeans. 6 Risk to terrestrial invertebrates from alpha-cypermethrin use is not evaluated, rather the potential hazard to honey bees and earthworms (i.e. the 

available data) are qualitatively assessed. 

2.6.6. Integration of Exposure and Effects

Exposure and toxicity data are integrated in order to evaluate the risks of adverse ecological 

effects on non-target species. For the screening-level risk assessment of alpha-cypermethrin, the

deterministic risk quotient (RQ) method is used to compare estimated exposure concentrations 

with measured toxicity values. The RQ method involves dividing point estimates of 

environmental concentrations by acute and chronic toxicity values. The resulting unitless RQs 

are then compared to the Agency’s Levels of Concern (LOC) (USEPA, 2004) (Table 2.3). 

These criteria are used to indicate when applications of alpha-cypermethrin, as directed on the 

proposed labels, have the potential to cause adverse effects to listed and non-listed non-target 

organisms.
-Page 21 of 126-

Table 2.3. Agency Risk Quotient (RQ) Metrics and Levels of Concern (LOC) Per Risk 

Class.

RISK CLASS RISK DESCRIPTION RQ LOC

Aquatic Animals (fish and invertebrates)

Acute Potential for effects to non-listed animals from acute 

exposures

Peak EEC/LC501 0.5

Acute 

Restricted Use

Potential for effects to animals from acute exposures

Risks may be mitigated through restricted use classification Peak EEC/LC501 0.1

Acute Listed 

Species

Listed species may be potentially affected by acute 

exposures

Peak EEC/LC501 0.05

Chronic Potential for effects to non-listed and listed animals from 

chronic exposures

60-day EEC/NOAEC 

(fish) 1

21-day EEC/NOAEC 

(invertebrates)

Aquatic Plants

Non-Listed Potential for effects to non-listed plants from exposures Peak EEC/LC501 1

Listed Potential for effects to listed plants from exposures Peak EEC/NOAEC 1

Terrestrial Animals (mammals and birds)

Acute Potential for effects to non-listed animals from acute 

exposures

EEC2/LC50 (Dietary) 0.5

EEC/LD50 (Dose)

Acute 

Restricted Use

Potential for effects to animals from acute exposures

Risks may be mitigated through restricted use classification

EEC2/LC50 (Dietary) 0.2

EEC/LD50 (Dose)

Acute Listed 

Species

Listed species may be potentially affected by acute 

exposures

EEC2/LC50 (Dietary) 0.1

EEC/LD50 (Dose)

Chronic Potential for effects to non-listed and listed animals from 

chronic exposures EEC 2

/NOAEC 1

Terrestrial and Semi-Aquatic Plants

Non-Listed Potential for effects to non-target, non-listed plants from 

exposures

EEC/ EC25 1

Listed Plant Potential for effects to non-target, listed plants from 

exposures

EEC/ NOAEC

1

EEC/ EC05

1 LC50 or EC50. 2 Based on upper bound seeding rates.

3. Analysis

3.1. Use Characterization

Alpha-cypermethrin is proposed for use as an emulsifiable concentrate. Proposed application 

methods for alpha-cypermethrin include, aerial, air blast, ground spray, and chemigation. 

Proposed maximum application rates and use patterns listed by use according to the proposed 

labels are provided in Table 3.1. 

Table 3.1. Proposed Maximum Use Patterns of Alpha-Cypermethrin.

Crop/Use Maximum Maximum Application Maximum Method of 
-Page 22 of 126-

Application 

Rate

(lbs a.i./A)

Number of 

Applications

Interval 

(days)

Yearly 

Application

(lbs a.i./A/yr)

Application

Alfalfa 0.025 3 7 0.075 Ground or air

Brassica vegetables 0.025 6 7 0.15 Ground or air

Citrus fruits 0.025 8 14 0.20 Ground or air

Corn (field, pop, seed) 0.025 4 3 0.10

Ground, air, 

banded or 

infurrow

Corn (sweet) 0.025 6 3 0.15 Ground or air

Cotton 0.025 6 3 0.15

Ground, air, 

banded or 

infurrow

Cucurbits 0.025 6 7 0.15 Ground or air

Fruiting vegetables 0.025 6 7 0.15 Ground or air

Leafy vegetables 0.025 6 7 0.15 Ground or air

Legume vegetables 0.025 6 5 0.15 Ground or air

Rice (grain, straw) 0.025 4 7 0.10 Ground or air

Root and tuber 

vegetables (except 

sugar beet)

0.025 6 4 0.15

Ground or air

Sorghum (and other 

cereals) 0.025 5 10 0.125 Ground or air

Soybeans 0.025 6 7 0.15 Ground or air

Sugar beets 0.025 6 7 0.15 Ground or air

Tree nuts 0.025 5 7 0.125 Ground or air

Wheat 0.025 5 14 0.125 Ground or air

3.2. Exposure Characterization

3.2.1. Environmental Fate and Transport Characterization

The general physical/chemical properties of alpha-cypermethrin are summarized in Table 3.2.

These data represent cypermethrins (i.e., data in most cases were generated for the racemic 

mixture, but are bridged across the enriched isomers). Where appropriate, data generated using 

the enriched alpha-cypermethrin as the test material, are identified. Data specific to alphacypermethrin were used to fulfill environmental fate and transport data requirements, and where 

there are no data specific for alpha, data were bridged from the database for the cypermethrins 

(zeta and racemic cypermethrin). Environmental fate and transport properties of alphacypermethrin are characterized in further detail in the following sections, and data specific to 

alpha-cypermethrin are noted. The Agency’s understanding of these properties is limited by the 

available dataset. Data submitted using alpha-cypermethrin as the test material is summarized in 

Appendix B.

Table 3.2 General Physical and Chemical Properties of Alpha-Cypermethrin

Parameter Value Reference

PC code 209600 --

CAS No. 67375-30-8 --
-Page 23 of 126-

Parameter Value Reference

Structure --

Chemical name 

(IUPAC)

racemate comprising (R)-α-cyano-3-phenoxybenzyl (1S,3S)-3-

(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate and 

(S)-α-cyano-3-phenoxybenzyl (1R,3R)-3-(2,2-dichlorovinyl)-2,2-

dimethylcyclopropanecarboxylate

or

racemate comprising (R)-α-cyano-3-phenoxybenzyl (1S)-cis-3-

(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate and 

(S)-α-cyano-3-phenoxybenzyl (1R)-cis-3-(2,2-dichlorovinyl)-2,2-

dimethylcyclopropanecarboxylate

--

Chemical name (CAS) (R)-cyano(3-phenoxyphenyl)methyl (1S,3S)-rel-3-(2,2-

dichloroethenyl)-2,2-dimethylcyclopropanecarboxylate

--

Common name Alpha-Cypermethrin (BAS 310 40 I) --

Chemical formula C22 H19 CI2NO3 --

Molecular weight 416.3 g/mol USEPA 2006b

Water solubility (20oC, 

pH 7)

4.0x10-3 mg/L Laskowski (2002)

Vapor pressure (25oC) 2.5x10-9 mm Hg Laskowski (2002)

Henry's law constant 3.4x10-7 atm-m3

/mol Laskowski (2002)

Octanol-water 

partitioning coefficient 

Log KOW (20oC, pH 7)

6.4 Laskowski (2002)

Alpha-cypermethrin has a strong soil adsorption (Koc = 144,662), based on FAO Soil Mobility 

Classification and a tendency to partition to sediment in aquatic systems. The reported log 

octanol/water partition coefficient value (6.4) suggests that the cypermethrins have the potential 

to bioaccumulate in aquatic organisms, assuming that chemical metabolism is negligible. The 

cypermethrins have a high molecular weight of 416.3 g/mmol. With a vapor pressure of 2.5x10-9

mm Hg and a limited solubility, the calculated Henry’s Law Constant for the cypermethrins is 

relativiely low (3.4x10-7 atm-m3/mol). Table 3.2 lists various important physicochemical 

characteristics of the chemicals. A summary of the submitted environmental fate and transport 

data is provided in Table 3.3.

Laboratory studies have indicated that alpha-cypermethrin degrades through a combination of 

biotic and abiotic reactions and is slightly to moderatley persistent in the environment, based on 

Goring et al. (1975). Under acidic and neutral conditions this compound is relatively stable to 

hydrolysis, but is readily hydrolyzed under alkaline conditions with a half-life of approximately 

2 days at pH 9. Alpha-cypermethrin is susceptible to aqueous photolysis with a half-life of 5

days. Cypermethrins are shown to biodegrade in aerobic and anaerobic soils with half-lives on 
-Page 24 of 126-

the order of about 2 months (one month for alpha cypermethrin) and in aerobic and anaerobic 

aquatic systems with half-lives on the order of one to two weeks (alpha specific data is of the 

same range). Alpha-cypermethrin is considered immobile in soils based on the FAO soil mobility 

classification (Koc as high as 144,662 L/Kg) and its potential to leach into groundwater is low

(USEPA, 2006a). If released to water, alpha-cypermethrin will rapidly partition to the sediment 

compartment which acts as an environmental sink for this compound. Alpha-cypermethrin may

bioconcentrate moderately in fish (BCF = 448X in whole fish), with moderate depuration. In 

terrestrial field dissipation studies alpha-cypermethrin was not very persistent in soils and did not

leach (half-lives 1-2 weeks). In supplemental aquatic field dissipation studies (zetacypermethrin), the chemical appears to persist in the sediment, with reported half-lives of 126 

and 181 days in LA and CA, respectively.

Table 3.3 Environmental Fate Data Summary for Alpha-Cypermethrin

Property Value / Degradates observed Reference 

Hydrolysis half-life: pH 5

 pH 7

 pH 9

stable

stable

1.8 (acid labeled) and 2.5 days (alcohol label)

cis/trans-DCVA (max. 79% at 120 hr) and 3-

phenoxybenzaldehyde (max. 65% at 120 hr)

Alpha-cypermethrin:

67 days (pH 7, 25oC)

MRID 42620501

MRID 48425002

Aqueous photolysis half-life 36.2 days

3-PBA (max. 35% at 35 days)

Alpha-cypermethrin:

5 days

MRID 42395701

MRID 48425003

Soil photolysis half-life sandy loam 55 days

cyperamide (steadily increased to a max. of 13.3%)

MRID 42129001

Aerobic soil metabolism 

half-life

60.7 days (sandy loam, acid label)

59.8 days (sandy loam, alcohol label)

cis/trans-DCVA (max. 24% at 62 days, study duration 150 

days)

Alpha-cypermethrin:

28 days (UK sandy loam soil)

MRID 42156601

MRID 4845006

Anaerobic soil metabolism 

half-life

53.3 days (sandy loam, acid label)

63 days (sandy loam, alcohol label)

cis/trans-DCVA (max. 33% 30 days after flooding), 3-PBA 

(max. 26% at 60 days after flooding or end of study)

MRID 42156602

Aerobic aquatic metabolism 8.9 days MRID 45920801
-Page 25 of 126-

Property Value / Degradates observed Reference 

half-life 10.1 days

trans-DCVA (max. 49% at 30 days), cis-DCVA (max. 19% 

at 30 days), 3-PBA (max. 42% at 30 days); study duration, 

90 or 183 days.

Alpha-cypermethrin:

2.8 – 11 days

MRID 48425011, 

48425012

Anaerobic aquatic 

metabolism half-life

13.8 days (clay loam, benzyl label)

16.5 days (clay loam, cyclopropyl label)

DCVA (max. 34% at 71 days)

MRID 44876105

Adsorption coefficient

Koc (L/Kg)

----------------------------------

Aged Column Leaching 

Study

328,500 (Sand)

134,900 (Sandy loam)

82,600 (Silty loam) 

20,800 (Clay loam)

Alpha-cypermethrin:

26,492 – 144,662

-------------------------------------------------------------------------

Degradate cis/trans-DCVA found at up to 13.2% in the 

leachate

MRID 42129003

MRID 48425008

----------------------

MRID 42129002

Terrestrial Field Dissipation 

Study

13 days (CA soil)

5 days (LA soil)

MRID 42459601

Bioconcentration factor 

(BCF)

161X edible portion

448X whole fish

883X non-edible

moderately slow depuration, with 10-15% of residues 

remaining after 21 days of depuration

MRID 42868203

3.2.1.1. Transport and Mobility

Alpha-cypermethrin is considered immobile in soil. Soil organic carbon adsorption coefficients 

(Koc) for cypermethrin ranged from approximately 21,000 to 328,500 L/Kg in four soils (sand, 

sandy loam, silty loam and clay). If released into water, cypermethrin rapidly partitions to the 

sediment column. The tendency to adsorb to soil and sediment along with the relatively low 

vapor pressure (2.5x10-9 mm Hg) and Henry’s law constant (3.4x10-7 atm-m3

/mol), indicates that 

volatilization from water and soil will not be an important transport process. It can be concluded 

that the cypermethrin degradates 3-PBA and trans-DCVA have a high potential for mobility as 

they were weakly sorbed to four soils tested. 3-PBA was slightly more sorbed (Koc values 

ranging from 118 to 215) to the tested soils than was trans-DCVA (Koc values ranging from 18 

to 48). 

3.2.1.2. Degradation

Cypermethrin labeled with 14C at the cyclopropyl and benzyl moieties was relatively stable at pH 

5 and 7 buffered solutions, but degraded rapidly with half-lives of approximately 2 days in pH 9 
-Page 26 of 126-

solutions. The major degradation products of the base catalyzed hydrolysis of cypermethrin 

were cis- and trans- DCVA (maximum 79% at 120 hours or study duration) and 3-

phenoxybenzaldehyde (maximum 65% at 120 hours). Photolysis of cypermethrin in distilled 

water occurs slowly, but the rate of degradation appears to be enhanced in natural waters, which 

contain humic and fulvic acids. A photolysis half-life of 5 days was observed for alphacypermethrin in pH 7 aqueous buffered solution exposed to sunlight in California from March to 

April. Shorter half-lives on the order of less than 1 to 4 days were observed for cypermethrin 

dissolved in river water, seawater and distilled water with 1% humic acid exposed to sunlight 

(Takahashi et al. 1985). The half-life for thin films of cypermethrin in a sandy loam soil matrix 

was approximately 55 days; however, degradation was also observed in control samples and the 

dark control corrected half-life is over 100 days. The only transformation product observed was 

cyperamide, at 13.3% at the end of the study (35 days). Cypermethrin degraded with a half-life 

of approximately 60 days in a fine sandy loam soil maintained at 25 o

C and held under aerobic 

conditions (28 days for alpha-cypermethrin). Carbon dioxide and a mixture of cis- and transDCVA (maximum 24% at 62 days in a 150 day study) were the major degradation products.

Under aquatic conditions, cypermethrin degraded more rapidly than in soil (8.9-10.1 days in a 

supplemental aerobic aquatic study and 13.8-16.5 days in an anaerobic aquatic study). 

Degradation products (see Table 3.4 for structures) under aerobic aquatic conditions included 

trans-DCVA (max. 49% at 30 days), cis-DCVA (max. 19% at 30 days) and 3-PBA (max. 42% at 

30 days, study duration 183 days). Under anaerobic conditions, the only degradation product 

was DCVA at 34% at 71 days (study duration 90 days for benzyl label and 183 days for 

cyclopropyl label).

Figure 3.4. Nomeclature and Structures of Potential Degradation Products of AlphaCypermethrin

Common Name Chemical Name Structure

DCVA 3-(2,2-

dichloroethenyl)-

2,2-dimethylcyclopropane carboxylic 

acid 

3-phenoxybenzaldehyde
-Page 27 of 126-

3-PBA 3-phenoxybenzoic 

acid 

cyperamide

3.2.1.3. Field Studies

Terrestrial field dissipation studies conducted in Madera, CA and Cheneyville, LA indicated that 

the field dissipation half-life of formulated cypermethrin is approximately 1 to 2 weeks. 

Cypermethrin in the form of Ammo 2.5 EC was applied three times at 0.2 lb ai/acre/application 

to a bare silt loam soil (78-82% sand, 14-20% silt, 2-4% clay, 0.2-0.6% OM, pH 6.5-7.2) located 

in Madera, California and soil samples were analyzed for cypermethrin and potential degradates 

cis-DCVA, trans-DCVA, and 3-PBA. Cypermethrin was detected in 3-6" cores collected 

immediately after each application (18, 8, and 33 μg/kg), and on day 2 (20 μg/kg) and day 4 (29 

μg/kg) following the third application. Cypermethrin was detected at 10 μg/kg in one 6-12" core 

collected 2 days after the final application, but it was not detected in any soil cores collected 

below this depth (detection limit of 7 μg/kg). The degradate 3-PBA was detected in 0-3" cores 

collected immediately after the second application (8 μg/kg), immediately after the third 

application (17 μg/kg), and the following days after the third application: day 2 (25 μg/kg), day 4 

(32 μg/kg), day 7 (25 μg/kg), day 14 (24 μg/kg), day 21 (8 μg/kg), and day 28 (7 μg/kg). It was 

not detected above a detection limit of 7 μg/kg in any soil cores collected below 3 inches. 

Potential degradates cis- and trans-DCVA were not detected above the detection limit of 7 μg/kg 

in any of the soil cores. An analysis of the cypermethrin concentration as a function of time 

yielded a field dissipation half-life of 13 days. 

In a second study, cypermethrin in the form of Ammo 2.5 EC was applied three times at 0.2 lb 

a.i./acre/application to a bare loamy sand soil (30% sand, 64% silt, 6% clay, 0.7% OM, pH 7.0) 

located in Cheneyville, LA. The soil cores were analyzed for cypermethrin and potential 

degradates cis-DCVA, trans-DCVA, and 3-PBA. Based upon dissipation in the top 0-3" soil 

cores, the dissipation half-life for cypermethrin was 5 days. Cypermethrin was not detected 

above a detection limit of 7 μg/kg in any cores collected below 3 inches. The degradate trans-
-Page 28 of 126-

DCVA was detected in 0-3" cores collected on the following days after the third application: day 

2 (16 μg/kg) and day 7 (8 μg/kg). The degradate 3-PBA was detected in 0-3" cores collected 

immediately after the second application (10 μg/kg), immediately after the third application (20 

μg/kg), and 2 days after the 3rd application (44 μg/kg). The degradate cis-DCVA was not 

detected above a detection limit of 7 μg/kg in any of the soil cores. None of the analytes were 

detected above a detection limit of 7 μg/kg in any of the soil cores collected below 3 inches.

Given the large number of registered uses, additional data under this guideline (835.6100, 

Terrestrial Field Dissipation) are needed to describe variability across the U.S.

There are two supplemental aquatic field dissipation studies conducted with zeta-cypermethrin in 

California and Louisiana. The half-lives were 181 days and 126 days, respectively. These halflives are not similar to those observed in the laboratory studies. Nevertheless, the reported halflives included the sediments only.

A POTW study to determine the fate of the cypermethrins (racemic, alpha-, and zetacypermethrin) in sewage treatment works is being requested to to ascertain whether indoor and 

urban cypermethrin uses contribute to toxicity in receiving waters or sediments after discharge of 

treated sewage.

3.2.1.4. Bioconcentration

The reported value of log octanol/ water partition coefficient of 6.4 suggests that alphacypermethrin has the potential to bioaccumulate in aquatic organisms assuming that chemical 

metabolism is negligible. Maximum BCFs for the alpha-cypermethrin are 161x for edible tissue, 

883x for viscera, and 448x for whole fish (MRID 42868203, study conducted with racemic 

cypermethrin). Depuration appeared to be moderately slow, with ~10-15% of the initial residues 

remaining after 21 days. Thus, it appears that there is potential for bioaccumulation/ 

bioconcentration in aquatic organisms. However, alpha-cypermethrin is being metabolized 

extensively in the fish, which suggests a reduceded potential for alpha-cypermethrin to 

biomagnify in terrestrial organisms. 

3.2.2. Measures of Aquatic Exposure
-Page 29 of 126-

3.2.2.1. Surface Water Exposure

The Tier II model Pesticide Root Zone Model (PRZM v3.12.2; May 12, 2005; Carousel et al., 

undated) linked with EXposure Analysis Modeling System (EXAMS v2.98.4.6; Apr. 25, 2005; 

Burns, 2004) via the PRZM/EXAMS model shell (PE v5.0, Nov. 15, 2006), i.e., 

PRZM/EXAMS) and the Tier I Rice Model (v1.0, May 8, 2007) were used to estimate screeninglevel exposure concentrations in aquatic environments. The PRZM model simulates pesticide 

movement and transformation on and across the agricultural field resulting from crop 

applications. The EXAMS model simulates pesticide concentrations in water due to loading via 

runoff, erosion, and spray drift, assuming a standard 1-ha pond, 2-m deep (20,000 m3) with no 

outlet that borders a 10-ha treated field. Simulations are for multiple (usually 30) years, from 

which the Agency estimates peak values that are expected to recur on average once every ten 

years, based on time series of daily estimated concentrations. The coupled PRZM and EXAMS 

models and user’s manuals are available from the U.S. Environmental Protection Agency Water 

Models web-page (USEPA, 2011b).

Exposure estimates generated using the standard pond are intended as surrogates for potential 

concentrations in a wide variety of vulnerable water bodies, including prairie potholes, playa 

lakes, vernal pools, other wetlands, man-made and natural ponds, and ephemeral and first-order 

streams. Innumerable site-specific factors will tend to make such water bodies more or less 

vulnerable than the standard pond. Static water bodies that have larger ratios of pesticide-treated 

drainage area to water body volume are generally expected to have higher peak concentrations 

than the standard pond’s EECs. Such water bodies may be smaller in size, and/or have larger 

drainage areas. However such water bodies may be more likely to overflow and discharge 

pesticide in their effluent, whereas the standard pond has no discharge. As watershed size 

increases, it becomes increasingly unlikely that the entire watershed is planted with a single crop 

that is all treated simultaneously with a pesticide. Headwater streams may have peak 

concentrations that are higher than those predicted for the standard pond, but such concentrations 

will likely persist for only short periods of time or distance, as they are carried downstream and 

diluted with water originating elsewhere.

Estimations regarding the spray drift fraction in the PRZM/EXAMS model runs were based upon 

the Tier I mode of AgDRIFT® program. The primary assumption is that the wind speeds at each 

site are generally below 10 mph. This is consistent with the label language that indicates “Make 

aerial or ground applications when the wind velocity favors on target product deposition 

(approximately 3 to 10 mph). Do not apply when wind velocity exceeds 15 mph.” However, 

there may be uncertainty with respect to unconcerned applicators that would apply the chemical 

at wind speeds above 10 mph.

There is uncertainty with respect to the level of mitigation that a buffer zone of 150 ft plus a 

vegetative strip of 10 ft can provide. The estimation of spray drift was obtained from 

AgDRIFT®; however, there is no way to know how well the buffer zone will protect the bodies 

of water from runoff. In certain cases, the level of runoff is the most important factor, rather 

than the level of spray drift. This is an assumption made in the Tier I calculation of AgDRIFT®.
-Page 30 of 126-

The Tier I Rice Model was used to estimate screening-level exposure to alpha-cypermethrin that 

may occur in water bodies receiving release water from rice paddies that were treated with alphacypermethrin. This model was used to assess the proposed use on rice seed because the 

PRZM/EXAMS exposure models do not specifically address the unique rice growing 

environment and the model is approved for use in risk assessment. The model produces a single 

exposure value that represents a dissolved concentration within a rice paddy. This single value is 

used to approximate both acute and chronic exposures.

The Tier I Rice Model relies on an equilibrium partitioning concept to provide conservative 

exposure estimates resulting from application of pesticides to rice paddies. When a pesticide is 

applied to a rice paddy, the model assumes instantaneous partitioning between the water and 

sediment phases. The model does not account for pesticide degradation, mass transfer between 

the aqueous phase and the sediment, volatilization, dilution, or other potentially important 

attenuation processes; therefore the model provides an upper-bound estimate of exposure for 

alpha-cypermethrin which is proposed for use on rice as a foliar spray by air or ground 

equipment. The Tier I Rice Model was calibrated to generate estimates that are consistent with or 

conservative for dissolved concentrations measured within rice paddies and in discharged paddy 

water. The model was not evaluated or calibrated for concentrations measured in sediment and 

does not account for residues bound to suspended sediment. A description of and guidance for 

using the Tier I Rice Model may be found on the U.S. Environmental Protection Agency (EPA) 

Water Models web-page (USEPA, 2011b).

The general chemical and environmental fate data for alpha-cypermethrin listed in Table 3.2-3.3

were used for generating model input parameters for PRZM and EXAMS (listed in Table 3.5). 

Chemical specific and model input values were chosen in accordance with current divisional 

guidance (USEPA, 2009). Where data was submitted specific to alpha-cypermethrin, these data 

are identified below in Table 3.5.

Table 3.5. PRZM and EXAMS Surface Water Chemical Input Parameters for Alphacypermethrin.

Parameter (units) Value(s) Sources Comments

Chemical Name alpha-cypermethrin Label Proposed label 

KOC 141,700 MRID: 42129003 Represents the average KOC value 

among four values ranging from 20,800 

to 328,000 ml/g; the KOC model was 

utilized as per recommendation of the 

SAP.

Aerobic Soil Metabolism 

(days)

69.8 MRID: 42156601

MRID: 48425003

Represents the 90th percentile of the 

upper confidence bound on the mean of 

three half-life values two for 

cypermethrin = 60.7 and 59.8 days, and 

one for alpha = 28 days; mean = 69.8 

days; std. dev. = 18.6 days

Buffer Zone (ft.) 25 ground

150 aerial

Label --

Application Efficiency 

(fraction)

0.99 for ground

0.95 for aerial

--- EFED guidance on input parameters for 

PRZM/EXAMS, v2.1, dated 

10/22/2009

Spray Drift (fraction) 0.039 AgDRIFT Crops that are applied by aerial 
-Page 31 of 126-

Parameter (units) Value(s) Sources Comments

applications. Otherwise default to 

USEPA, 2009 input guidance.

Solubility in Water (ppm) 0.0040 Laskowski, 2002 At 20°C. Laskowski, 2002 Rev. 

Environ. Contam. Toxicol. 174:49-170

Aerobic Aquatic 

Metabolism (days)

10.7 MRID 45920801 Represents the 90th percentile of the 

upper confidence bound on the mean of 

two half-life values: 8.9 and 9.8 days; 

mean = 9.35 days; std. dev. = 0.64 days

Anaerobic Aquatic 

Metabolism (days)

18.1 MRID 42156602 Represents the 90th percentile of the 

upper confidence bound on the mean of 

two half-life values: 13.8 and 16.5 

days; mean = 15.15 days; std. dev. = 

1.35 days

Hydrolysis at pH 7(days) 67 MRID 48425003 Data specific for alpha-cypermethrin

Aqueous Photolysis @ pH 

7 (days)

5 MRID 48425003 Data specific for alpha-cypermethrin

Molecular Weight (g/mole) 416.3 Laskowsky 2002 Laskowski, 2002 Rev. Environ. 

Contam. Toxicol. 174:49-170

Vapor Pressure (torr or 

mmHg)

2.5 x 10-9 Laskowsky 2002 Laskowski, 2002 Rev. Environ. 

Contam. Toxicol. 174:49-170

Henry’s Law Constant

(atm-m3/mol)

3.4 x 10-7 Laskowsky 2002 Laskowski, 2002 Rev. Environ. 

Contam. Toxicol. 174:49-170

The scenarios selected for modeling purposes in PRZM/EXAMS were used to represent the 

maximum application rates for all alpha-cypermethrin uses, except rice. Table 3.7 presents the 

model inputs for application type and method as well as the scenarios selected for each modeled 

use. 

Table 3.7. PRZM/EXAMS Model Input Parameters for Alpha-cypermethrin Application 

Methods

Use Scenario

Metfile Application 

Rate 

lbs a.i./A 

(kg a.i./ha)

Apps per 

Year

Interval 

(days) 

Date of 

Initial 

App.

(dd-mm)

App.

Method 

(CAM)

Alfalfa ILalfalfaNMC.txt 14842.dvf 0.025 3 7 01-06 Aerial (2)

Brassica/cucurbits 

vegetables1

FLCucumbersST

D.txt 12844.dvf 0.025 6 7 16-10 Aerial (2)

Citrus fruit FLCitrusSTD.txt 12844.dvf 0.025 8 14 01-02 Ground 

spray (2)

Corn (field, pop, 

seed) ILcornSTD.txt 14842.dvf 0.025 4 3 01-06 Aerial (2)

Corn (sweet) ILcornSTD.txt 14842.dvf 0.025 6 3 01-06 Aerial (2)

Cotton MScottonSTD.txt 03940.dvf 0.025 6 3 01-06 Aerial (2)

Legume vegetables MSsoybeanSTD.t

xt

03940.dvf 0.025 6 5 01-06 Aerial (2)

Root and tuber 

vegetables

MNsugarbeetSTD

.txt

14914.dvf 0.025 6 4 01-06 Aerial (2)

Sorghum (and other 

cereals)

KSsorghumSTD.t

xt

13996.dvf 0.025 5 10 01-06 Aerial (2)

Sugar beets MNsugarbeetSTD 14914.cvf 0.025 6 7 01-06 Aerial (2)
-Page 32 of 126-

.txt

Tomatoes (fruiting 

vegetables)

FLtomatoSTD_V

2.txt 12448.dvf 0.025 6 7 16-10 Aerial(2)

Tree nuts GApecansSTD.txt 93805.dvf 0.025 5 7 21-09 Aerial (2)

Wheat NDwheatSTD.txt 14914.dvf 0.025 5 14 01-06 Aerial (2)

Rice Tier I Rice Model -- 0.025 4 7 Aerial

1 Use represents brassica vegetables, cucurbits, and leafy vegetables.

For the rice use, the Tier I Rice Model was used to estimate screening-level exposure to alphacypermethrin that may occur in water bodies receiving applications of alpha-cypermethrin. This 

model uses the application rate for rice (0.028 kg a.i./ha, 4 applications for a total of 0.112 kg/ha) 

and the organic carbon partitioning coefficient for alpha-cypermethrin (141,700 mL/g oc). The 

Tier I rice model inputs are listed below in Table 3.8.

Table 3.8. Tier I Rice Model Inputs

Compound Application Rate 

(kg/ha/yr)

Koc Kd

Alpha-cypermethrin 0.1 (0.028, 4x) 141,700 1417

The aquatic EECs resulting from the proposed alpha-cypermethrin uses (listed in Table 3.9) 

were used for risk estimation in this screening-level assessment. Example model input and 

output supporting these values is provided in Appendix C.

Table 3.9. Modeled Aquatic Surface Water 1-in-10-year EECs for Proposed Uses of Alphacypermethrin

Uses Max. App. Rate

(lbs a.i./A/yr) Peak (ppb) 21-day (ppb) 60-day (ppb)

Alfalfa 0.075 0.04 0.01 0.004

Brassica vegetables1 0.15 0.07 0.01 0.01

Citrus fruit 0.2 0.17 0.02 0.01

Corn (field, pop, seed) 0.1 0.32 0.03 0.02

Corn (sweet) 0.15 0.45 0.04 0.03

Cotton 0.15 0.62 0.06 0.03

Legume vegetables 0.15 0.25 0.03 0.01

Root and tuber vegetables 0.15 0.08 0.02 0.01

Sorghum (and other 

cereals) 0.125 0.21 0.03 0.02

Sugar beets 0.15 0.08 0.01 0.01

Tomato 0.15 0.08 0.01 0.01

Tree nuts 0.125 0.20 0.02 0.01

Wheat 0.125 0.08 0.01 0.01

Rice

(Tier I Rice Model) 0.1 0.54 <0.54 <0.54

1 Use represents brassica vegetables, cucurbits, and leafy vegetables.
-Page 33 of 126-

3.2.2.2. Sediment Pore Water Exposure

Environmental fate data show that alpha-cypermethrin readily dissipates from the water column 

but not from aquatic systems in their entirety, as it has been detected in sediment and the high 

propensity for the compound to bind to organic matter; therefore sediment exposure may be a 

concern for sediment-dwelling organisms. Benthic sediment pore water EECs were calculated 

for the proposed maximum use patterns for alpha-cypermethrin. Pore-water EECs are provided 

in Table 3.10. Note that the Tier I Rice Model does not estimate pore water concentrations.

Table 3.10. 1-in-10 year Pore Water EECs for Proposed Uses of Alpha-cypermethrin

Uses Max. App. Rate

(lbs a.i./A/yr) Peak (ppb) 21-day (ppb) 60-day (ppb)

Alfalfa 0.075 0.001 0.001 0.001

Brassica vegetables1 0.15 0.002 0.001 0.001

Citrus fruit 0.2 0.003 0.002 0.002

Corn (field, pop, seed) 0.1 0.005 0.004 0.003

Corn (sweet) 0.15 0.008 0.007 0.005

Cotton 0.15 0.01 0.007 0.005

Legume vegetables 0.15 0.004 0.003 0.002

Root and tuber vegetables 0.15 0.002 0.002 0.001

Sorghum (and other cereals) 0.125 0.005 0.004 0.003

Sugar beet 0.15 0.001 0.001 0.001

Tomato 0.15 0.002 0.002 0.001

Tree nuts 0.125 0.005 0.004 0.003

Wheat 0.125 0.001 0.001 0.001

1 Use represents brassica vegetables, cucurbits, and leafy vegetables.

3.2.3. Measures of Terrestrial Exposure

3.2.3.1. Terrestrial Wildlife

Exposure estimates for terrestrial animals assumed to be in the target area or in an area exposed 

to spray drift are derived using the T-REX model (version 1.4.1, 10/08/2008). This model 

incorporates the Kenaga nomograph, as modified by Fletcher et al. (1994), which is based on a 

large set of actual field residue data. The upper limit values from the nomograph represent the 

95th percentile of residue values from actual field measurements (Hoerger and Kenaga 1972). 

Consideration is given to different types of feeding strategies for mammals and birds, including 

herbivores, insectivores and granivores. For dose-based exposures, three weight classes of birds 

(20, 100, and 1000 g) and mammals (15, 35 and 1000 g) are considered. Given that no data on 

interception and subsequent dissipation from foliar surfaces are available for alpha-cypermethrin, 

a default foliar dissipation half-life of 35 days is used based on the work of Willis and McDowell 

(1987). Input parameters used in T-REX are provided in Table 3.11. The dietary-based EECs on 

a variety of food items from the proposed new uses of alpha-cypermethrin are provided in Table 
-Page 34 of 126-

3.12; dose-based EECs are provided in Table 3.13 (see Appendix B for example T-REX 

outputs).

Table 3.11. Input parameters used in T-REX (v1.4.1) to determine terrestrial EECs for 

alpha-cypermethrin spray application scenarios.

Crop/Use

Maximum 

Application 

Rate

(lbs a.i./A)

Foliar HalfLife (days)1

Application 

Interval

(days)

Maximum 

Number of 

Applications

Alfalfa 0.025 35 7 3

Brassica vegetables2 0.025 35 7 6

Citrus fruits 0.025 35 14 8

Corn (field, pop, seed) 0.025 35 3 4

Corn (sweet) 3 0.025 35 3 6

Legume vegetables 0.025 35 5 6

Rice (grain, straw) 0.025 35 7 4

Root and tuber 

vegetables (except 

sugar beet)

0.025 35 4 6

Sorghum (and other 

cereals) 0.025 35 10 5

Tree nuts 0.025 35 7 5

Wheat 0.025 35 14 5 1 Default foliar half-life in T-REX (v1.4.1) 2 Use represents brassica vegetables, cucurbits, fruiting vegetables, leafy vegetables, soybeans, and sugar beets.

3 Use represents corn (sweet) and cotton.

Table 3.12. Dietary-based EECs for alpha-cypermethrin spray application scenarios.

Crop/Use

Dietary-based EECs (mg a.i./kg)

Short Grass Tall Grass

Broadleaf 

Plants/Small 

Insects

Fruits/Pods/S

eeds/Large 

Insects

Alfalfa 15.77 7.23 8.87 0.99

Brassica vegetables1 26.18 12.00 14.72 1.64

Citrus fruits 22.08 10.12 12.42 1.38

Corn (field, pop, seed) 22.00 10.08 12.38 1.38

Corn (sweet) 2 31.19 14.30 17.54 1.95

Legume vegetables 28.51 13.07 16.04 1.78

Rice (grain, straw) 19.73 9.04 11.10 1.23

Root and tuber 

vegetables (except 

sugar beet)

29.80 13.66 16.76 1.86

Sorghum (and other 

cereals) 20.99 9.62 11.81 1.31

Tree nuts 23.18 10.62 13.04 1.45

Wheat 18.58 8.52 10.45 1.16 1 Use represents brassica vegetables, cucurbits, fruiting vegetables, leafy vegetables, soybeans, and sugar beets. 2 Use represents corn (sweet) and cotton.

Table 3.13. Dose-based EECs for alpha-cypermethrin spray application scenarios.
-Page 35 of 126-

Crop/Use

Dose-Based EECs (mg a.i./kg)

Food Type Birds Mammals

20g 100g 1000g 15g 35g 1000g

Alfalfa

Short Grass 17.96 10.24 4.59 15.04 10.39 2.41

Tall Grass 8.23 4.69 2.10 6.89 4.76 1.10

Broadleaf Plants/Small 

Insects 10.10 5.76 2.58 8.46 5.85 1.36

Fruit/Pods/Seeds/ Large 

Insects 1.12 0.64 0.29 0.94 0.65 0.15

Seeds (Granivores) 0.25 0.14 0.06 0.21 0.14 0.03

Brassica 

vegetables1

Short Grass 29.81 17.00 7.61 24.96 17.25 4.00

Tall Grass 13.66 7.79 3.49 11.44 7.91 1.83

Broadleaf Plants/Small 

Insects 16.77 9.56 4.28 14.04 9.70 2.25

Fruit/Pods/Seeds/ Large 

Insects 1.86 1.06 0.48 1.56 1.08 0.25

Seeds (Granivores) 0.41 0.24 0.11 0.35 0.24 0.06

Citrus fruits

Short Grass 25.15 14.34 6.42 21.05 14.55 3.37

Tall Grass 11.53 6.57 2.94 9.65 6.67 1.55

Broadleaf Plants/Small 

Insects 14.15 8.07 3.61 11.84 8.18 1.90

Fruit/Pods/Seeds/ Large 

Insects 1.57 0.90 0.40 1.32 0.91 0.21

Seeds (Granivores) 0.35 0.20 0.09 0.29 0.20 0.05

Corn (field, pop, 

seed)

Short Grass 25.06 14.29 6.40 20.98 14.50 3.36

Tall Grass 11.49 6.55 2.93 9.61 6.64 1.54

Broadleaf Plants/Small 

Insects 14.10 8.04 3.60 11.80 8.16 1.89

Fruit/Pods/Seeds/ Large 

Insects 1.57 0.89 0.40 1.31 0.91 0.21

Seeds (Granivores) 0.35 0.20 0.09 0.29 0.20 0.05

Corn (sweet) 2

Short Grass 35.52 20.26 9.07 29.74 20.55 4.77

Tall Grass 16.28 9.28 4.16 13.63 9.42 2.18

Broadleaf Plants/Small 

Insects 19.98 11.39 5.10 16.73 11.56 2.68

Fruit/Pods/Seeds/ Large 

Insects 2.22 1.27 0.57 1.86 1.28 0.30

Seeds (Granivores) 0.49 0.28 0.13 0.41 0.29 0.07

Legume 

vegetables

Short Grass 32.47 18.52 8.29 27.18 18.79 4.36

Tall Grass 14.88 8.49 3.80 12.46 8.61 2.00

Broadleaf Plants/Small 

Insects 18.26 10.41 4.66 15.29 10.57 2.45

Fruit/Pods/Seeds/ Large 

Insects 2.03 1.16 0.52 1.70 1.17 0.27

Seeds (Granivores) 0.45 0.26 0.12 0.38 0.26 0.06

Rice (grain, 

straw)

Short Grass 22.47 12.81 5.74 18.81 13.00 3.01

Tall Grass 10.30 5.87 2.63 8.62 5.96 1.38

Broadleaf Plants/Small 

Insects 12.64 7.21 3.23 10.58 7.31 1.70

Fruit/Pods/Seeds/ Large 

Insects 1.40 0.80 0.36 1.18 0.81 0.19

Seeds (Granivores) 0.31 0.18 0.08 0.26 0.18 0.04

Root and tuber 

vegetables 

(except sugar 

beet)

Short Grass 33.94 19.36 8.67 28.41 19.64 4.55

Tall Grass 15.56 8.87 3.97 13.02 9.00 2.09

Broadleaf Plants/Small 

Insects 19.09 10.89 4.87 15.98 11.05 2.56

Fruit/Pods/Seeds/ Large 

Insects 2.12 1.21 0.54 1.78 1.23 0.28

Seeds (Granivores) 0.47 0.27 0.12 0.39 0.27 0.06
-Page 36 of 126-

Sorghum (and 

other cereals)

Short Grass 23.90 13.63 6.10 20.01 13.83 3.21

Tall Grass 10.96 6.25 2.80 9.17 6.34 1.47

Broadleaf Plants/Small 

Insects 13.45 7.67 3.43 11.26 7.78 1.80

Fruit/Pods/Seeds/ Large 

Insects 1.49 0.85 0.38 1.25 0.86 0.20

Seeds (Granivores) 0.33 0.19 0.08 0.28 0.19 0.04

Tree nuts

Short Grass 26.39 15.05 6.74 22.10 15.27 3.54

Tall Grass 12.10 6.90 3.09 10.13 7.00 1.62

Broadleaf Plants/Small 

Insects 14.85 8.47 3.79 12.43 8.59 1.99

Fruit/Pods/Seeds/ Large 

Insects 1.65 0.94 0.42 1.38 0.95 0.22

Seeds (Granivores) 0.37 0.21 0.09 0.31 0.21 0.05

Wheat

Short Grass 21.17 12.07 5.40 17.72 12.25 2.84

Tall Grass 9.70 5.53 2.48 8.12 5.61 1.30

Broadleaf Plants/Small 

Insects 11.91 6.79 3.04 9.97 6.89 1.60

Fruit/Pods/Seeds/ Large 

Insects 1.32 0.75 0.34 1.11 0.77 0.18

Seeds (Granivores) 0.29 0.17 0.08 0.25 0.17 0.04 1 Use represents brassica vegetables, cucurbits, fruiting vegetables, leafy vegetables, soybeans, and sugar beets.

2 Use represents corn (sweet) and cotton.

Alpha-cypermethrin exposures to terrestrial invertebrates are not quantitatively calculated for 

derivation of deterministic RQs. However, risk to this taxon is assessed qualitatively in the Risk 

Description, Section 4.2.

The models SIP v.1.0 and STIR v.1.0 were used to evaluate whether risk to terrestrial animals is 

of concern for drinking water or inhalation alone. Results for both models indicate that drinking 

water and inhalation alone are not routes of concern for terrestrial brids and mammals. Results 

are provided in Appendix D. 

Additionally, The KABAM model v 1.0 was used to estimate potential risks to birds and 

mammals from bioaccumulation of hydrophobic organic pesticides in freshwater aquatic 

ecostystems. Results for the highest use pattern, provided in Appendix D, indicate that risks to 

birds and mammals are low. This is likely a result of alpha-cypermethrin being metabolized 

extensively in the fish, as shown in the available BCF study with the bluegill sunfish (MRID 

42868203).

3.2.3.2. Terrestrial Plants

Exposure of naturally-occurring terrestrial and semi-aquatic (wetland) plant species is typically 

estimated using OPP’s TerrPlant (v1.2.2; USEPA, 2006b) model and is assumed to encompass 

areas outside the immediate use site. The TerrPlant model is used to derive EECs in runoff and 

drift for terrestrial and semi-aquatic plants near areas where alpha-cypermethrin has been 

applied. Runoff exposure is assessed in two scenarios: sheet and channel runoff. In the sheet 

runoff scenario, the treated area generating runoff is assumed to drain into an area with equal 

size containing seedlings, resulting in 1, 2, or 5% of the amount applied being deposited. In the 
-Page 37 of 126-

channel runoff scenario, a ten-to-one ratio of treatment area to receiving area results in 10, 20, or 

50% of the amount applied being deposited on soil with emerging or emerged seedlings. Spray 

drift is also a source of pesticide loading to non-target areas. TerrPlant estimates EECs based on 

application rate, application method, chemical solubility in water, type of runoff and default 

assumptions of drift. The EECs for terrestrial and semi-aquatic plants for a single application of 

alpha-cypermethrin could not be calculated because acceptable seedling emergence and 

vegetative vigor studies have not been submitted. However, a supplemental Tier II vegetative 

vigor study has been submitted and will be discussed in the Risk Description.

3.3. Ecological Effects Characterization 

In screening-level ecological risk assessments, effects characterization describes the types of 

effects a pesticide can have on aquatic and terrestrial organisms. To date, toxicity tests for 

amphibian or reptiles are not required; birds are used as surrogates for reptiles and terrestrialphase amphibians and freshwater fish are used as surrogates for aquatic-phase amphibians. This 

characterization is based on the registrant-submitted toxicity data for birds, mammals, fish, 

invertebrates, and plants for alpha-cypermethrin, two major degradates and a typical formulated 

product (BAS 310 40 I). No data were available in the public literature for alpha-cypermethrin

effects characterization (see below).

In addition to the data submitted in support of registration, the public version of ECOTOX 

(ECOTOXicity) database (USEPA, 2011) was searched for additional toxicity data from the 

open literature. The ECOTOX database is a publicly-available, quality-assured, comprehensive 

tool for locating toxicity data from the open literature and is maintained by EPA Mid-Continent

Ecology Division. More information on ECOTOX can be found at: http://www.epa.gov/ecotox. 

Research papers are thoroughly screened using standard procedures before being accepted into 

ECOTOX thereby ensuring consistent, high quality information. For alpha-cypermethrin and its 

degradates, no studies were identified in ECOTOX as of April 27, 2012. However, alphacypermethrin has been bridged with racemic cypermethrin and zeta-cypermethrin, which have 

thousands of available studies in ECOTOX.

Given that alpha-cypermethrin is a new active ingredient with no previous registration in the 

U.S. or any other country, it is assumed that no ecological incidents exist for alpha-cypermethrin.

However, alpha-cypermethrin has been bridged with racemic cypermethrin and zetacypermethrin (as discussed in Appendix A), which have 22 reported major incidents (15 fish, 2 

avian, 3 mammalian, and 2 terrestrial invertebrates) and 26 reported minor incidents (21 fish and 

wildlife, 4 plants, and 1 “other non-target”). Since alpha-cypermethrin has similar ecological fate 

and ecotoxicity profiles to racemic and zeta-cypermethrin, these incidents likely represent the 

potential incidents from the proposed alpha-cypermethrin uses. See Appendix E for more 

information on the reported incidents. 

3.3.1. Aquatic Toxicity Assessment

The most sensitive acute and chronic effects measurement endpoints available for alphacypermethrin exposure to freshwater and estuarine/marine species are summarized in Table 

3.13. Where there are no chemical specific data for alpha-cypermethrin, data are bridged from 
-Page 38 of 126-

the database available for the cypermethrins (racemic and zeta-cypermethrin) as described in 

Appendix A. All acceptable and supplemental studies available for the registration of alphacypermethrin are described below, and data are described in relation to the tested material (i.e., 

racemic cypermethrin, zeta-cypermethrin, or alpha-cypermethrin).

3.13. Summary of most sensitive endpoints from submitted aquatic toxicity studies for alpha-cypermethrin. 

Exposure 

Scenario Species Exposure Duration

Toxicity 

Reference 

Value

Effects Reference Toxicity 

Category

Freshwater Fish

Acute Rainbow 

trout

(Oncorhynch

us mykiss)

96 hours LC50 = 2.2 μg 

a.i./L

Mortality MRID 47944207

Acceptable

Very Highly 

Toxic

Chronic Fathead 

minnow

(Pimephales 

promelas)

30 days NOAEC = 0.14 

μg a.i./L

LOAEC = 0.33 

μg ai/L

Growth and 

mortality

MRID 00089039

Acceptable

NA

Freshwater Invertebrates

Acute Amphipod

(Hyalella 

azteca)

96 hours EC50 = 0.0036 

μg a.i./L

Mortality MRID 44423501

Acceptable

Very Highly 

Toxic

ChonicChroni

c

No adequate data submitted; to assess chronic risk to freshwater invertebrates, a surrogate NOAEC value of 

0.00059 μg a.i./L was derived based on acute-to-chronic ratio method using acute and chronic data for 

estuarine/marine invertebrates.a

Benthic Organisms

Sub-Chronic Amphipod

(Hyalella 

azteca)

10 days sediment value

(experimental 

data): 

NOAEC < 1.8 

μg a.i./kg 

sediment

LOAEC = 1.8

μg a.i./kg 

sediment

pore water value

(derived data) b

:

NOAEC < 

0.00182 μg 

a.i./L pore water 

LOAEC = 

0.00182 μg 

a.i./L pore water 

Mortality and 

Growth

MRID 44074406

Acceptable

Very Highly 

Toxic

Chronic No chronic data submitted; to assess chronic risk to benthic organisms, the surrogate chronic NOAEC value 

for pore water of 0.000781 μg a.i./L from the chronic mysid study will be used. c

Estuarine/Marine Fish

Very Highly 
-Page 39 of 126-

3.13. Summary of most sensitive endpoints from submitted aquatic toxicity studies for alpha-cypermethrin. 

Exposure 

Scenario Species Exposure Duration

Toxicity 

Reference 

Value

Effects Reference Toxicity 

Category

Acute Sheepshead 

minnow

(Cyprinidon

variegates)

96 hours LC50 = 0.95 μg 

a.i./L

Mortality MRID 00090075

Acceptable

Toxic

Chronic No adequate data submitted; to assess chronic risk to estuarine/marine fish, a surrogate NOAEC value of 

0.06 μg a.i./L was derived based on acute-to-chronic ratio method using acute and chronic data for 

freshwater fish.d

Estuarine/Marine Invertebrates

Acute Mysid 

shrimp

(Mysidopsis 

bahia)

96 hours e LC50 = 0.00475 

μg a.i./L

Mortality Acc. No. 070562

Acceptable

Very Highly 

Toxic

Chronic Mysid 

shrimp

(Mysidopsis 

bahia)

28 days NOAEC = 

0.000781 μg 

a.i./L

LOAEC = 

0.00197 μg/L

Weight of 

Females reduced

MRID 42725301

Acceptable

Very Highly 

Toxic

Aquatic Plants

Acute Lemna gibba 96 hours EC50 > 1.39 μg

a.i./L

NOAEC = 1.39 

μg a.i./L

No toxicity MRID

47944031

Supplemental

Toxicity 

categories are 

not specified

for plants

Acute Skeletonema 

costatum

96 hours EC50 > 33.5 μg 

a.i./L

NOAEC = 33.5 

μg a.i./L

No toxicity MRID

47944032

Acceptable

Toxicity 

categories are 

not specified

for plants

a The chonic NOAEC estimated for freshwater invertebrates is based on the acute-to-chronic ratio method determined by the 

following mathematical relationship: Estuarine/Marine invertebrate LC50 (0.00475 μg a.i./L) / Estuarine/Marine invertebrate 

NOAEC (0.000781 μg a.i./L) = Freshwater invertebrate LC50 (0.0036 μg a.i./L) / X (estimated value for Freshwater 

invertebrate NOAEC), where X = 0.00059 μg a.i./L. b For benthic organisms, the LOAEC value of 0.00182 μg a.i./L pore water was calculated as follows. The LOAEC value in 

whole sediment [1.8 μg a.i./kg sediment] is divided by the proportion of organic carbon in the sediment [0.0099 kg OC/kg 

whole sediment]. Thus, the LC50 value in units of OC is 182 μg a.i./kg OC [1.8 μg a.i./kg sediment ÷ 0.0099 kg OC/kg 

sediment]. The equivalent concentration in pore water is based on the definition of the Koc,

Koc (L/kg OC) = Sediment Conc in OC (mg/kg OC) ÷ Conc in pore water (mg/L).

By rearrangement,

Conc in water = Sediment Conc in units of OC ÷ Koc.

For the cypermethrins, the Koc is taken as 141,700 [L/kg OC]. Thus, the calculated concentration in pore water corresponding 

to the LOAEC value of 182 μg a.i./kg OC is 0.00182 μg a.i./L [182 μg a.i./kg OC ÷ 141,700 L/kg OC]. c

The chronic NOAEC value for the mysid shrimp (0.000781 μg a.i./L) will serve as a surrogate estimate of the chronic 

NOAEC for benthic organisms in units of μg a.i./L pore water. The mysid was selected as a surrogate because of similarities in 

life stages exposed during chronic toxicity tests for both species. In addition the LC50 value for the mysid shrimp and Hyalella 

azteca in 96-hour acute studies are very similar (LC50= 0.00475 μg a.i./L for mysid and LC50 = 0.0036 μg a.i./L) indicating 
-Page 40 of 126-

3.13. Summary of most sensitive endpoints from submitted aquatic toxicity studies for alpha-cypermethrin. 

Exposure 

Scenario Species Exposure Duration

Toxicity 

Reference 

Value

Effects Reference Toxicity 

Category

that these species experience similar toxicity to cypermethrin. 

d The chronic NOAEC estimate for estuarine/marine fish is based on the acute-to-chronic ratio method, determined by the 

following mathematical relationship: Freshwater fish LC50 (2.2 μg a.i./L)/ Freshwater fish NOAEC (0.14 μg a.i./L) = 

Estuarine/Marine fish LC50 (0.95 μg a.i./L)/ X (estimated value for Estuarine/Marine fish NOAEC), where X = 0.06 μg a.i./L. e

 The acute toxicity reference value identified to calculate acute RQs for estuarine/marine invertebrates is for a 96-hour 

exposure duration, rather than the guideline recommended 48-hour exposure duration. Although 48-hour LC50 values have 

been reported in other studies, these values are higher than the 96-hour LC50 of 0.005 μg a.i./L. Taking the most conservative 

approach, EFED will use the lowest LC50 value reported for estuarine/marine invertebrates.

3.3.1.1 Toxicity to Freshwater Fish

The acute toxicity of technical grade racemic cypermethrin to freshwater fish was evaluated in 

several species, with 96-hour LC50 values ranging from 0.39 μg a.i./L in rainbow trout (MRID 

44546027) to 4.5 μg a.i./L in bluegill sunfish (MRID 44546030). Based on these results, 

racemic cypermethrin is categorized as very highly toxic to freshwater fish on an acute basis. 

Studies assessing the acute toxicity of two racemic cypermethrin formulations and one alphacypermethrin formulation in rainbow trout were also submitted. The racemic cypermethrin 

formulations tested were GFU 061(36% a.i.) and GFU 070 (25.1% a.i.); and the alphacypermethrin formulation tested was BASF 310 40 I (10.5% a.i.). The 96-hour LC50 values 

reported for GFU 061, GFU 070 and BASF 310 40 I are 4.7 μg formulation/L (MRID 

00065813), 13.0 μg formulation/L (MRID 00088947) and 2.2 μg 40ormulation.i./L (MRID 

47944207, respectively, indicating that these formulations are very highly toxic to freshwater 

fish. Comparison of the 96-hour LC50 value for racemic cypermethrin TGAI (0.39 μg a.i./L) and 

cypermethrin formulations (2.2 to 13.0 μg 40ormulation.i./L) indicates that the formulated 

products have a similar order of toxicity to technical grade cypermethrin.

Acute toxicity studies in freshwater fish were also submitted for the racemic cypermethrin 

degradate 3-PBA in rainbow trout (MRID 00089037) and bluegill sunfish (MRID 00089038). 

Results yield 96-hour LC50 values of 13.3 and 36.3 mg degradate/L in rainbow trout and bluegill 

sunfish, respectively. Based on these 96-hour LC50 values, 3-phenoxy benzoic acid is 

categorized as slightly toxic to freshwater fish on an acute basis and is much less toxic than 

cypermethrin TGAI to freshwater fish.

An early life-stage study in fathead minnow was submitted by the registrant to establish the 

chronic toxicity of racemic cypermethrin to freshwater fish (MRID 00089039). Results of this 

30-day exposure study showed that survival was significantly reduced compared to controls at 

0.33 μg a.i./L, yielding a 30-day NOAEC value for survival of 0.14 μg a.i./L. No treatmentrelated effects were observed for hatchability or growth. No acceptable chronic toxicity studies 

for cypermethrin formulations or cypermethrin degradates to freshwater fish were submitted.

3.3.1.2. Toxicity to Freshwater Invertebrates
-Page 41 of 126-

Acute toxicity studies of technical grade racemic cypermethrin to freshwater invertebrates 

available include a 96-hour LC50 value for zeta-cypermethrin of 0.0036 μg a.i./L in Hyalella

azteca (MRID 44423501), a 48-hour EC50 value for racemic cypermethrin of 0.42 μg a.i./L in 

in daphnid (MRID 44546031) and a 48-hour EC50 value for alpha-cypermethrin of 0.067 μg 

a.i./L om daphnids (MRID 47944208). Based on these results, racemic cypermethrin can be 

categorized as very highly toxic on an acute basis. Though data on the acute toxicity of alphacypermethrin is available for the daphnid, the amphipod Hyalella azteca is known to be more 

acutely sensitive to pyrethroids, such as alpha-cypmerthrin. Therefore, taking the most 

conservative approach, the lowest LC50 value reported for zeta-cypermethrin (96-hour LC50

value of 0.0036 μg a.i./L) is used to evaluate acute toxic exposure of freshwater invertebrates to 

alpha-cypermethrin.

Studies assessing the acute toxicity of three racemic cypermethrin formulations and one alphacypermethrin formulation to daphnids were submitted. The racemic cypermethrin formulations 

tested were GFU 034/A (36% a.i.), GFU 061 (36% a.i.), GFU 070 (24% a.i.); the alphacypermethrin formulation tested was BASF 310 40 I (10.5% a.i.). Results of these studies were 

reported as EC50 values (for immobility), rather than LC50 values. The 48-hour EC50 values 

ranged from 0.64 μg a.i./L (MRID 47944208) to 21.6 μg a.i./L (MRID 89040), indicating that 

these formulations are very highly toxic to daphnidson an acute basis. Comparison of the 48-

hour LC50/EC50 values for racemic cypermethrin TGAI (0.42 to 2.0 μg a.i./L) and racemic 

cypermethrin formulations (0.64 to 21.6 μg a.i./L) indicates that the formulated products have a 

similar order of toxicity to technical grade racemic cypermethrin.

Acute toxicity tests in freshwater invertebrates using the degradate 3-PBA to daphnids were also 

submitted. Results yield 48-hour EC50 values of 89.0 mg degradate/L (MRID 152739) and 111 

mg degradate/L (Acc. No. 070562). Based on these acute toxicity values, 3-phenoxy benzoic 

acid is categorized as practically non-toxic to slightly toxic to freshwater invertebrates on an 

acute basis. Thus, the 3-phenoxy benzoic acid degradate is much less toxic than the 

cypermethrins TGAI to freshwater invertebrates.

No valid chronic toxicity studies on the technical grade alpha-cypermethrin in freshwater 

invertebrates were submitted. Acute-to-chronic ratios based on available acute toxicity data 

were calculated based on the following mathematical relationship:

Estuarine/marine invertebrate LC50 (0.00475μg a.i./L) / Estuarine/marine invertebrate 

NOAEC (0.000781μg a.i./L) = Freshwater invertebrate LC50 (0.0036 μg a.i./L)/ X 

(estimated value for Freshwater invertebrate NOAEC), where X = 0.00059 μg a.i./L. 

Several studies on the toxicity of racemic cypermethrin TGAI to benthic organisms have been 

submitted. Studies were conducted using two types of experimental protocols, exposure in a 

water-only system and exposure in a water-sediment system. In the water system studies, 

organisms were exposed to racemic cypermethrin in overlying (surface) water; no sediment was 

present in the test chamber (these studies are discussed with the freshwater invertebrate studies 

above). For studies conducted using the water-sediment system protocol, racemic cypermethrin 
-Page 42 of 126-

was applied to water-sediment systems and allowed to settle for 2 days; organisms were 

introduced to the above water-sediment systems, and toxicity was assessed after a 10-day 

exposure period. However, these studies present a degree of uncertainty because of the lack of 

equilibration of spiked sediments with the pore water (e.g., equilibration should have occurred 

for at least one month). While compounds bound to the sediment present potential toxicity 

concerns, those residues that have reached equilibrium in the pore water are considered a greater 

source of toxic risk to benthic invertebrates (Di Toro et al., 1991). Therefore the studies 

presented in this assessment may underestimate sediment toxicity. 

Two studies on racemic cypermethrin TGAI were conducted using a water-sediment system, one 

study with midge (MRID 44074402) and one study with amphipod (MRID 44074406). Both 

studies were conducted using the same protocol, as described above, using sediments from three 

sources (Florissant, Mississippi, and Duluth). All toxicity values for these studies are expressed 

in terms of the concentration of racemic cypermethrin in sediment (μg a.i./kg) on Day 0. 

Measurement of racemic cypermethrin in sediment and surface water on Days 0 and 10 of 

exposure indicates that the water-sediment system was not at equilibrium, thus adding 

uncertainty to the results of these studies. Results yield 10-day NOAEC values ranging from less 

than 1.8 μg a.i./kg sediment (Florrisant sediment) in amphipods, to 25 μg a.i./kg sediment 

(Mississippi sediment) for midge. LC50 values ranged from 3.6 μg a.i./kg sediment (Florissant 

sediment) in amphipods to 67 μg a.i./kg sediment in midge (Mississippi sediment). In general, 

toxicity decreased (as reflected by higher LC50 values), with increasing organic carbon content of 

the sediment. Since a definitive NOAEC value is not available for the most sensitive benthic 

invertebrate/sediment test (amphipod/Florrisant sediment), the lowest 10-day LOAEC value of 

1.8 μg a.i./kg sediment in amphipods will be used to characterize the lower bounds of risk from

acute exposure of benthic organisms to alpha-cypermethrin TGAI in sediment.

In order to assess the risk of sub-chronic exposure to benthic organisms to the alphacypermethrin TGAI based on pore water concentrations, the equivalent toxicity value in pore 

water is derived using the lowest 10-day LOAEC value of 1.8 μg a.i./kg sediment in amphipods. 

The LOAEC value in whole sediment [1.8 μg a.i./kg sediment] is divided by the proportion of 

organic carbon (OC) in the sediment [0.0099 kg OC/kg whole sediment]. Thus, the LOAEC

value in units of OC is 182 μg a.i./kg OC [1.8 μg a.i./kg sediment ÷ 0.0099 kg OC/kg sediment]. 

The equivalent concentration in pore water is based on the definition of the Koc,

Koc (L/kg OC) = [sediment (mg/Kg OC)] / [pore water (mg/L)]

By rearrangement,

[water] = [sediment (mg/Kg OC)] / Koc

For the cypermethrins, the Koc is 141,700 [L/kg OC] (MRID 42129003). Thus, the calculated 

concentration in pore water corresponding to the LC50 value of 364 μg a.i./kg OC is 0.00128 μg 

a.i./L [182 μg a.i./kg OC ÷ 141,700 L/kg OC]. To assess risk of acute exposure to benthic 

organisms to alpha-cypermethrin TGAI in terms of pore water concentrations, the derived 

LOAEC value of 0.00182 μg a.i./L is used.
-Page 43 of 126-

Chronic toxicity studies for the most sensitive benthic organisms, Hyalella azteca, were not 

submitted. Previous assessments for racemic and zeta-cypermethrin calculated acute-to-chronic 

ratios based on the available acute and chronic toxicity data for the mysid shrimp because the 

mysid shrimp is a crustacean and its life cycle is more closely related to the most sensitive 

amphipod, Hyalella azteca, than the daphnid. For this assessment, however, the chronic mysid 

NOAEC value of 0.000781 μg a.i./kg will be used as a surrogate value to assess chronic risk to 

benthic organisms from exposure in pore water because of the difficulties in applying an acuteto-chronic ratio to the available sub-chronic data in order to calculate a chronic endpoint. 

3.3.1.3. Toxicity to Estuarine/Marine Fish

The acute toxicity of technical grade racemic cypermethrin to estuarine/marine fish was 

evaluated in sheepshead minnow and Atlantic salmon, with 96-hour LC50 values of 0.95 μg a.i./L 

(MRID 00090075) and 4.3 μg a.i./L (MRID 41968212) respectively, indicating that the racemic 

cypermethrin TGAI is very highly toxic to estuarine/marine fish on an acute basis. Taking the 

most conservative approach, the lowest 96-hour LC50 value of 0.95 μg a.i./L in sheepshead 

minnow will be used to evaluate acute toxic exposure to estuarine/marine fish. No acute toxicity 

studies of cypermethrin formulations or cypermethrin degradates in estuarine/marine fish were 

submitted.

No valid chronic toxicity studies on technical grade alpha-cypermethrin in estuarine/marine fish 

were submitted. Acute-to-chronic ratios based on available acute toxicity data were calculated 

based on the following mathematical relationship: 

Freshwater LC50 (0.39 μg a.i./L) / Freshwater NOAEC (0.14 μg a.i./L) = 

Estuarine/Marine LC50 (0.95 μg a.i./L)/ X (estimated value for Estuarine/Marine 

NOAEC), where X = 0.34 μg a.i./L. 

This estimated NOAEC of 0.34 μg a.i./L is > 0.1 of the 60-day EEC 1, indicating the need for 

fish full life cycel studies per 40 CFR Part 158. No chronic toxicity studies for the formulations 

or degradates of the cypermethrins in estuarine/marine fish were submitted. This is identified as 

a data gap. 

3.3.1.4. Toxicity to Estuarine/Marine Invertebrates

Acute toxicity tests with estuarine/marine invertebrates using racemic cypermethrin TGAI were 

conducted with several species including shrimp, molluscs, crab and lobster. Toxicity values 

(EC50 and LC50) reported for shrimp range from the 96-hour LC50 value of 0.00475 μg a.i./L 

(Acc. No. 070562) to the 96-hour LC50 value of 0.01 μg a.i./L (MRID 41068003). Similar 

results were observed in lobster (96-hour LC50 = 0.04 μg a.i./L; MRID 41068003) and fiddler 

crab (96-hour LC50 = 0.197 μg a.i./L; MRID 89045). Based on these results, the racemic 

cypermethrin TGAI is categorized as very highly toxic to estuarine/marine shrimp and 

 1 60-d EEC of 0.131 μg a.i./L (based on North Carolina Fruit and coarse droplets, from the RED) ÷ estimated 

saltwater NOAEC (0.34 μg a.i./L, see calculations above) = 0.4.
-Page 44 of 126-

crustaceans. Results of acute toxicity tests in molluscs show that the racemic cypermethrin 

TGAI is moderately to highly toxic to oysters, with a 96-hour EC50 value of 0.37 mg a.i./L in 

Eastern oyster (MRID 89049) and a 48-hour LC50 value of >2.27 mg a.i./L in Pacific oyster 

(Acc. No. 070562). Results of these studies indicate that molluscs are less susceptible than 

crustaceans to racemic cypermethrin toxicity on an acute basis. Taking the most conservative 

approach, the 96-hour LC50 value of 0.00475 μg a.i./L in mysid shrimp will be used to calculate

acute risk to estuarine/marine invertebrates from exposure to alpha-cypermethrin. No acute 

toxicity studies for the formulations or degradates of the cypermethrins in estuarine/marine 

invertebrates were submitted. 

Three studies involving life-cycle tests in mysid shrimp were submitted by the registrant to 

establish the chronic toxicity of racemic cypermethrin to estuarine/marine invertebrates. The 

NOAEC values reported in these studies range from 0.781 ng a.i./L for effects on first generation 

mortality, male length and weight and female weight (MRID 42725301), to 1.5 ng a.i./L for 

number of offspring (Acc. No. 070562) and survival and reproduction (MRID 44546035). 

Taking the most conservative approach, the lowest NOAEC value of 0.781 ng a.i./L will be used 

to characterize chronic risk to estuarine/marine invertebrates from exposure to alphacypermethrin. 

3.3.1.5. Toxicity to Aquatic Plants

The acute toxicity of technical grade alpha-cypermethrin to aquatic vascular plants was evaluated 

for Lemna gibba, with a 96-hour EC50 greater than 1.39 μg a.i./L (MRID# 47944031; 

supplemental). The acute toxicity of technical grade alpha-cypermethrin to aquatic non-vascular 

plants was evaluated for Skeletonema costatum, with a 96-hour EC50 greater than 33.5 μg a.i./L

(MRID# 47994032; acceptable). Additional supplemental studies are available for the aquatic 

non-vascular plants Anabaena flos-aquae, Navicula pelliculosa, and Pseudokirchneriella 

supcapitata that indicate these species are not as sensitive to alpha-cypermethrin as S. costatum. 

3.3.2 Terrestrial Effects Characterization

The most sensitive acute and chronic toxicity reference values available for alpha-cypermethrin

exposure to mammals, birds, and terrestrial invertebrates are summarized in Table 3.14. Where 

there are no chemical specific data for alpha-cypermethrin, data are bridged from the database 

available for the cypermethrins (racemic and zeta-cypermethrin) as described in Appendix A. 

The most sensitive measurement endpoints for alpha-cypmermethrin exposure to terrestrial 

plants are presented in Table 3.15. All acceptable and supplemental studies available for the 

registration of alpha-cypermethrin are described below, and data are described in relation to the 

tested material (i.e., racemic cypermethrin, zeta-cypermethrin, or alpha-cypermethrin). 

Table 3.14 Summary of most sensitive endpoints from submitted terrestrial toxicity studies 

for alpha-cypermethrin. 

Species 

(common 

name)

Taxa 

Represented Endpoint Effect

Test 

Substance 

(% a.i.)

Reference/ 

Classification

Acute 

Toxicity 

Classification
-Page 45 of 126-

Table 3.14 Summary of most sensitive endpoints from submitted terrestrial toxicity studies 

for alpha-cypermethrin. 

Species 

(common 

name)

Taxa 

Represented Endpoint Effect

Test 

Substance 

(% a.i.)

Reference/ 

Classification

Acute 

Toxicity 

Classification

Rattus 

norvegicus

(Laboratory 

Rat)

Mammals

LD50 = 86 mg 

a.i./kg-bw Mortality TGAI

MRID# 

41776115

Acceptable

Moderately 

toxic

NOAEC = 5 mg 

a.i./kg/day Decrased 

F1 pup 

weight and 

growth

TGAI

MRID# 

00090040

Acceptable

Not 

LOAEC = 25 mg Applicable

a.i./kg/day

Bobwhite 

quail (Colinus 

virginianus)

Birds, 

terrestrialphase 

amphibians, 

and reptiles

LD50 >2025 mg 

a.i./kg bw Mortality TGAI

MRID# 

47944015

Acceptable

Practically 

non-toxic

Zebra finch 

(Taeniopygia 

guttata)

LD50 = 1370 mg 

a.i./kg-bw Mortality TGAI

MRID 

47944016

Supplemetnal

Slightly toxic

Mallard duck

(Anas 

platyrhynchos)

LC50 >4690 mg 

a.i./kg diet Mortality TGAI

MRID# 

47944017

Acceptable

Practically 

non-toxic

Bobwhite 

quail (Colinus 

virginianus)

Mallard duck

(Anas 

platyrhynchos)

NOAEC = 50 mg 

a.i./kg-diet

No toxicity

TGAI MRID# 

00090073

Acceptable

MRID# 

00090074

Acceptable

Not 

Applicable

LOAEC > 50 mg 

a.i./kg-diet TGAI Not 

Applicable

Apis mellifera

(Honey bee)

Terrestrial 

invertebrates

Contact LD50 = 

0.023 μg a.i./bee Moratlity TGAI

Acc. No. 

260647

Acceptable

Very highly 

toxic

Oral

LD50 = 0.172 μg 

a.i./bee Mortality TGAI Very highly 

toxic

Table 3.15 Summary of most sensitive endpoints from submitted terrestrial plant 

toxicity studies for alpha-cypermethrin. 

Crop Species Endpoint Concentration Test 

Substance Reference/ 

Classification

Seedling Emergence

N/A N/A N/A N/A N/A N/A

Vegetative Vigor

Monocot Onion EC25

> 0.0266 lbs a.i./A

Fresh weight TGAI MRID

47944210

NOAEC < 0.00333 lbs a.i./A TGAI Supplemental
-Page 46 of 126-

Dicot Oilseed Rape EC25

> 0.0266 lbs a.i./A

Fresh weight TGAI

NOAEC 0.0133 lbs a.i./A TGAI

3.3.2.1. Toxicity to Mammals

Mammalian toxicity data submitted to the Agency’s Health Effects Division (HED) are used to 

approximate toxicity to wild mammals. These studies are typically conducted with laboratory 

rats (Rattus norvegicus) or mice (Mus musculus). No studies evaluating toxicity to wild mammal 

species are available, or have been submitted to the Agency for any of the cypermethrins. 

Available mammalian studies were presented in the HED chapter of the Reregistration Eligibility 

Decision Document (RED) for cypermethrin (US EPA, 2006). 

The reported laboratory rat acute oral LD50 value is 86 mg/kg-bw for racemic cypermethrin 

(MRID 41776115). The acute dermal LD50 >4920 mg/kg /day for racemic cypermethrin, based 

on a study conducted with rats (MRID 00056800). An acute inhalation study conducted with rats 

resulted in an LC50 >2.5 mg/L for cypermethrin (MRID 42395702). Based on the reported 

laboratory rat oral LD50 value, cypermethrin has moderate acute toxicity to small mammals.

In the available 3-generation rat reproduction study, the NOAEL is 5 mg/kg/day based on 

decreased F1 pup body weight and body weight gain (MRID 00090040). In the submitted 

chronic mammalian dietary study with racemic cypermethrin, the NOAEL is 6 mg/kg/day based 

on clinical signs of neurotoxicity and mortality in males at the 20.4 mg/kg/day treatment level 

and decreased body weights in females at the 18.1 mg/kg/day treatment level (MRID 44536801). 

3.3.2.2. Toxicity to Birds

The results of the single acute oral toxicity study available for the cypermethrins indicate that the 

racemic cypermethrin is practically non-toxic to avian species on an acute oral basis. The acute 

oral LD50 value for bobwhite quail (Colinus virginianus) is >2000 mg a.i./kg-bw and no clinical 

signs of toxicity were observed at any treatment level (MRID 44546024). 

Acute oral toxicity of alpha-cypermethrin to a passerine species was evaluated for the zebra finch 

(Taeniopygia guttata). The study (MRID 47944016) is classified as supplemental for qualitative 

use only. In addition to signs of stress in all treatment and control groups, diarrhea was evident in 

all treatment groups, calling into question the effective dose received by the animals. However, 

results of this study indicate that alpha-cypermethrin is slightly toxic to passerine birds (LD50 = 

1370 mg a.i./kg-bw).

The results of the sub-acute dietary toxicity studies available for alpha-cypermethrin and racemic 

cypermethrin indicate that they can be classified as practically non-toxic to avian species on an 

acute dietary basis. The LC50 for cypermethrin is greater than 2,634 mg a.i./kg-diet for mallard 

duck (Anas platyrhynchos) (MRID 00090071) and and LC50 for alpha-cypermethrin is greater 
-Page 47 of 126-

than 4,690 mg a.i./kg-diet for bobwhite quail (MRID 47944017). In these studies, the LC50 value 

was determined based on the repellent nature of the treated feed, which resulted in decreased 

food consumption and body weight. 

The results of avian reproduction studies available for racemic cypermethrin showed no adverse 

effects at 50 mg a.i./kg-diet, which was the highest dose tested. 

3.3.2.3. Toxicity to Terrestrial Invertebrates

The Agency guidelines for terrestrial invertebrate tests are for honey bees (Apis mellifera). The 

acute contact LD50 value for alpha-cyperemthrin is 0.033 μg a.i./bee and the oral LD50 value for 

racemic cypermethrin is 0.172 μg a.i./bee (Accession Number 260647). Based on these results, 

the alpha-cypermethrin and racemic cypermethrin are classified as ‘highly toxic’ to honey bees 

on an acute exposure basis. 

In addition, the Agency received one semi-field study and one field study for the honey bee 

(MRIDs 47944204 and 47944206, respectively; both are classified as supplemental for 

qualitative use only). Though there are certain limitations with these studies, including a lack of 

residue analysis to confirm the integrity and independence of the control and treatment groups, 

they do provide information on the risks of alpha-cypermethrin exposure to honey bees. Both 

studies suggest that honey bee mortality increases after exposure to alpha-cypermethrin in a 

semi-field or field setting. 

3.3.2.4. Toxicity to Terrestrial Plants

The acute toxicity of technical grade alpha-cypermethrin to terrestrial plants was evaluated for 

monocots (onion, Allium cepa; and oat, Avena sativa) and dicots (pea, Pisum sativum; oilseed 

rape, Brassica napus; carrot, Daucus carota; and sunflower, Helianthus annuus). The study 

(MRID 47944210) is classified as supplemental for qualitative use only because a definitive 

EC25 and NOAEC were not determined for the most sensitive monocot endpoint (onion fresh 

weight), in addition to other guideline deviations (e.g., study was conducted with TGAI instead 

of the recommended TEP). However, a definitive NOAEC value of 0.0133 lbs a.i/A was 

determined for the most sensitive dicot endpoint (oilseed rape fresh weight). This NOAEC value 

represents roughly half of the maximum single application rate for the proposed uses of alphacypermethrin and suggests that risks to plants may be possible. This information may be used in 

risk characterization for plants. 

4. Risk Characterization

4.1. Risk Estimation

Toxicity data and exposure estimates are used to evaluate the potential for adverse ecological 

effects on non-target species. This screening-level assessment for alpha-cypermethrin relies on 

the deterministic RQ method to provide a metric of potential risks. The RQ provides a 

comparison of exposure estimates to toxicity endpoints (i.e., the estimated exposure 
-Page 48 of 126-

concentrations are divided by acute and chronic toxicity values). The resulting unitless RQs are 

compared to the Agency’s LOCs, as shown in Table 2.3. LOCs are used by the Agency to 

indicate when the use of a pesticide, as directed by the label, has the potential to cause adverse 

effects to non-target organisms.

4.1.1. Aquatic Organisms 

The highest screening-level aquatic EECs based on the maximum application rates for each 

proposed use pattern were used to derive RQs. These exposure estimates represent 

concentrations in surface water (Table 3.9). Peak EECs are used to represent acute exposure to 

fish, aquatic invertebrates, and aquatic plants, and the highest 21-day and 60-day average EECs 

represent chronic exposure to aquatic invertebrates and fish, respectively. Because of alphacypermethrin’s persistence, each subsequent year may be affected by the previous year’s 

application. 

4.1.1.1. Fish and Invertebrates

Table 4.1 lists RQs calculated for fish and invertebrates (freshwater and estuarine/marine)

exposed to alpha-cypermethrin, based on the acute EECs generated from PRZM/EXAMS and 

Tier I Rice Model modeling scenarios. Results of acute toxicity studies in freshwater and 

estuarine/marine fish (Table 3.13) indicate that alpha-cypermethrin is “highly toxic” to 

freshwater fish on an acute exposure basis. RQs for freshwater and estuarine/marine fish are 

above the Agency’s acute risk to listed species LOC (0.05) for the proposed uses of alphacypermethrin, as well as the Agency’s acute risk to non-listed species LOC of 0.5 for some of the 

proposed uses. RQs for freshwater and estuarine/marine invertebrates are all well above the 

acute risk to non-listed species LOC for all of the proposed uses. 
-Page 49 of 126-

Table 4.1. Acute Risk Quotients for Fish and Invertebrates Exposed to Alpha-Cypermethrin 

at the Highest EECs Using the Most Sensitive of the Available Endpoints.

Use

EECs

(ppb)

Freshwater Fish 

RQs

LC50 = 2.2 μg 

ai/L

Freshwater 

Invertebrate RQs

LC50 = 0.0036 μg 

ai/L

Estuarine/Marine 

Fish RQs

LC50 = 0.95 μg 

ai/L

Estuarine/Marine 

Invertebrate RQs

LC50 = 0.00475 μg 

ai/L

Peak Acute1,2 Acute1,2 Acute1,2 Acute1,2

Alfalfa 0.04 0.02 11.111 0.04 8.421

Brassica 

vegetables3 0.07 0.03 19.441 0.072 14.741

Citrus fruit 0.17 0.082 47.221 0.181 35.791

Corn (field, pop, 

seed) 0.32 0.152 88.891 0.341 67.371

Corn (sweet) 0.45 0.212 125.001 0.472 94.741

Cotton 0.62 0.282 172.221 0.651 130.531

Legume 

vegetables 0.25 0.112 69.441 0.262 52.631

Root and tuber 

vegetables 0.08 0.04 22.221 0.082 16.841

Sorghum (and 

other cereals) 0.21 0.102 58.331 0.222 44.211

Sugar beets 0.08 0.04 22.221 0.082 16.841

Tomato 0.08 0.04 22.221 0.082 16.841

Tree nuts 0.20 0.092 55.561 0.212 42.111

Wheat 0.08 0.04 22.221 0.082 16.841

Rice 

(Tier I Rice 

Model)

0.54 0.242 150.001 0.571 113.681

1 Acute risk to non-listed species LOC for aquatic fish is 0.5 2 Acute risk to listed species LOC for aquatic fish is 0.05

3 Use represents brassica vegetables, cucurbits, fruiting vegetables, leafy vegetables, soybeans, and sugar beets.

Table 4.2 lists the chronic RQs for fish and invertebrates (freshwater and estuarine/marine) 

exposed to alpha-cypermethrin. RQs for chronic exposures to freshwater and estuarine/marine 

fish fell below the Agency’s chronic risk to listed and non-listed species LOC (1.0) for all of the 

proposed uses of alpha-cypermethrin except for the proposed use on rice. However, RQs for 

chronic exposures to freshwater and estuarine/marine invertebrates are well above the chronic 

risk to listed and non-listed species LOC. The Tier I rice model only calculates a peak 

concentration in the water that is released from the rice field immediately following application 

of the compound. Therefore, chronic EECs can only be estimated less than the peak since there 

would be some amount of degradation and/or dissipation between when the peak occurs 

(immediately following application) and 21 or 60 days following the application.
-Page 50 of 126-

Table 4.2. Chronic Risk Quotients for Fish and Invertebrates Exposed to AlphaCypermethrin at the Highest EECs Using the Most Sensitive of the Available Endpoints.

Use

EECs

(ppb)

Freshwater 

Fish RQs

NOAEC = 

0.14 μg ai/L

Freshwater 

Invertebrate RQs

NOAEC = 

0.00059 μg ai/L

Estuarine/Marine 

Fish RQs

NOAEC = 0.06

μg ai/L

Estuarine/Marine 

Invertebrate RQs

NOAEC = 0.000781 

μg ai/L

21-day 60-day Chronic Chronic Chronic Chronic

Alfalfa 0.01 0.004 0.03 16.95 0.07 12.80

Brassica 

vegetables1 0.01 0.01 0.07 16.95 0.16 12.80

Citrus fruit 0.02 0.01 0.07 33.90 0.16 25.61

Corn (field, 

pop, seed) 0.03 0.02 0.14 50.85 0.33 38.41

Corn 

(sweet) 0.04 0.03 0.21 67.80 0.50 51.22

Cotton 0.06 0.03 0.21 101.69 0.50 76.82

Legume 

vegetables 0.03 0.01 0.07 50.85 0.16 38.41

Root and 

tuber 

vegetables

0.02 0.01

0.07 33.90 0.16 25.61

Sorghum 

(and other 

cereals)

0.03 0.02

0.14 50.85 0.33 38.41

Sugar beet 0.01 0.01 0.07 16.95 0.16 12.80

Tomato 0.01 0.01 0.07 16.95 0.16 12.80

Tree nuts 0.02 0.01 0.07 33.90 0.16 25.61

Wheat 0.01 0.01 0.07 16.95 0.16 12.80

Rice 

(Tier I Rice 

Model)

<0.54 <0.54 NA NA NA NA

1 Use represents brassica vegetables, cucurbits, fruiting vegetables, leafy vegetables, soybeans, and sugar beets.

Bold values greater than chronic risk to listed and nonlisted aquatic animals LOC of 1.0

NA = Not applicable, Tier I rice model is not able to calculate.

Table 4.3 lists the acute and chronic RQs calculated for benthic organisms exposed to alphacypermethrin in pore water, based on the acute EECs generated from PRZM/EXAMS. Results 

of sub-chronic toxicity studies in benthic organisms (Table 3.13) indicate that alphacypermethrin is “highly toxic” to benthic invertebrates on an acute exposure basis. Sub-chronic

and chronic RQs for benthic organisms are above the Agency’s acute and chronic risk to listed 

and non-listed species. 
-Page 51 of 126-

Table 4.3. Acute and Chronic Risk Quotients for Benthic Invertebrates 

Exposed to Alpha-Cypermethrin at the Highest EECs Using the Most Sensitive 

of the Available Endpoints.

Use

Pore Water EECs

(ppb)

Benthic Invertebrate RQs

LOAEC = 0.00182 μg ai/L 

Benthic Invertebrate RQs

NOAEC = 0.000781 μg 

ai/L

21-day Sub-Chronic2 Chronic

Alfalfa 0.001 >0.55 1.28

Brassica 

vegetables1 0.001>0.55 1.28

Citrus fruit 0.002 >1.10 2.56

Corn (field, 

pop, seed) 0.004

>2.20 5.12

Corn (sweet) 0.007 >3.85 8.96

Cotton 0.007 >3.85 8.96

Legume 

vegetables 0.003

>1.65 3.84

Root and 

tuber 

vegetables

0.002

>1.10 2.56

Sorghum 

(and other 

cereals)

0.004

>2.20 5.12

Tree nuts 0.004 >2.20 5.12

Wheat 0.001 >0.55 1.28 1 Use represents brassica vegetables, cucurbits, fruiting vegetables, leafy vegetables, soybeans, and sugar beets.

2 Since the most sensitive toxicity endpoint from the sub-chronic benthic invertebrate study is a non-definitive 

endpoint, RQs represent the minimum RQ possible. The magnitude of the true RQ is uncertain. 

Bold values greater than chronic risk to listed and nonlisted aquatic animals LOC of 1.0

4.1.1.2. Aquatic Plants

Although alpha-cypermethrin does exhibit effects on both Lemna gibba and Skeletonema 

costatum, these effects are at much higher concentrations than those estimated for the highest 

proposed alpha-cypermethrin uses. For both taxa, both listed and nonlisted RQs are <0.01, while 

the LOCs are 1.0.

4.1.2. Terrestrial Organisms

4.1.2.1. Mammals

Acute and chronic dose-based and chronic dose-based RQs were calculated for the proposed new 

chemical uses of alpha-cypermethrin based on the information shown in Table 3.9. Dose-based 

acute mammalian RQs for the proposed new uses of alpha-cypermethrin range from < 0.01 to 

0.16 (as shown in Table 4.2). Most proposed uses result in acute listed species LOC 

exceedances, except for proposed uses on alfalfa and wheat. RQs that exceed the listed species 

LOC are for small and medium sized mammals exposed to alpha-cypermethrin on short grass 

only. LOCs were not exceeded for mammals exposed to alpha-cypermethrin on tall grass, 

broadleaf plants, small insects, fruits, pods, large insects, or seeds.
-Page 52 of 126-

Table 4.2. Mammalian Dose-Based Acute RQ Values for New Uses of Alpha-Cypermethrin.

Use

Application 

Rate

lbs ai/A

(#app)

Body 

Weight

(g)

Mammalian Acute Dose-based RQs for Specified Food Items

Short 

Grass Tall Grass

Broadleaf 

Plants/Small 

Insects

Fruits/Pods

/Lg Insects Seeds

Alfalfa 0.025

(3)

15 0.08 0.04 0.04 < 0.01 < 0.01

35 0.07 0.03 0.04 < 0.01 < 0.01

1000 0.04 0.02 0.02 < 0.01 < 0.01

Brassica 

vegetables1

0.025

(6)

15 0.13 0.06 0.07 0.01 < 0.01

35 0.11 0.05 0.06 0.01 < 0.01

1000 0.06 0.03 0.03 < 0.01 < 0.01

Citrus fruits 0.025

(8)

15 0.11 0.05 0.06 0.01 < 0.01

35 0.10 0.04 0.05 0.01 < 0.01

1000 0.05 0.02 0.03 < 0.01 < 0.01

Corn (field, 

pop, seed)

0.025

(4)

15 0.11 0.05 0.06 0.01 < 0.01

35 0.09 0.04 0.05 0.01 < 0.01

1000 0.05 0.02 0.03 < 0.01 < 0.01

Corn 

(sweet)2 0.025

(6)

15 0.16 0.07 0.09 0.01 < 0.01

35 0.13 0.06 0.08 0.01 < 0.01

1000 0.07 0.03 0.04 < 0.01 < 0.01

Legume 

vegetables

0.025

(6)

15 0.14 0.07 0.08 0.01 < 0.01

35 0.12 0.06 0.07 0.01 < 0.01

1000 0.07 0.03 0.04 < 0.01 < 0.01

Rice (grain, 

straw)

0.025

(4)

15 0.10 0.05 0.06 0.01 < 0.01

35 0.09 0.04 0.05 0.01 < 0.01

1000 0.05 0.02 0.03 < 0.01 < 0.01

Root and 

tuber 

vegetables 

(except 

sugar beet)

0.025

(6)

15 0.15 0.07 0.08 0.01 < 0.01

35 0.13 0.06 0.07 0.01 < 0.01

1000 0.07 0.03 0.04 < 0.01 < 0.01

Sorghum 

(and other 

cerials)

0.025

(5)

15 0.11 0.05 0.06 0.01 < 0.01

35 0.09 0.04 0.05 0.01 < 0.01

1000 0.05 0.02 0.03 < 0.01 < 0.01

Tree nuts 0.025

(5)

15 0.12 0.05 0.07 0.01 < 0.01

35 0.10 0.05 0.06 0.01 < 0.01

1000 0.05 0.02 0.03 < 0.01 < 0.01

Wheat 0.025

(5)

15 0.09 0.04 0.05 0.01 < 0.01

35 0.08 0.04 0.05 0.01 < 0.01

1000 0.04 0.02 0.02 < 0.01 < 0.01 1 Use represents brassica vegetables, cucurbits, fruiting vegetables, leafy vegetables, soybeans, and sugar beets. 2 Use represents corn (sweet) and cotton.

Bolded value indicates that the acute listed species LOC is exceeded (RQ > 0.1).

Chronic dose-based mammalian RQs for the proposed new uses of alpha-cypermethrin range 

from 0.01 to 2.71 (as shown in Table 4.3). All proposed uses result in chronic non-listed and 

listed species LOC exceedances for small and medium sized mammals exposed to alphacypermethrin on short grass. Chronic non-listed and listed species LOCs are also exceeded for 

small and medium sized mammals exposed to alpha-cypermethrin on tall grass, broadleaf plants, 
-Page 53 of 126-

and small insects for some of the proposed uses. RQs are higher for smaller mammals due to an 

increased food ingestion rate associated with the higher metabolic rate of smaller mammals. 

Table 4.3. Mammalian Dose-Based Chronic RQ Values for New Uses of AlphaCypermethrin.

Use

Application 

Rate

lbs ai/A

(#app)

Body 

Weight

(g)

Mammalian Chronic Dose-based RQs for Specified Food Items

Short 

Grass Tall Grass

Broadleaf 

Plants/Small 

Insects

Fruits/Pods

/Lg Insects Seeds

Alfalfa 0.025

(3)

15 1.37 0.63 0.77 0.09 0.02

35 1.17 0.54 0.66 0.07 0.02

1000 0.63 0.29 0.35 0.04 0.01

Brassica 

vegetables1

0.025

(6)

15 2.27 1.04 1.28 0.14 0.03

35 1.94 0.89 1.09 0.12 0.03

1000 1.04 0.48 0.58 0.06 0.01

Citrus fruits 0.025

(8)

15 1.92 0.88 1.08 0.12 0.03

35 1.64 0.75 0.92 0.10 0.02

1000 0.88 0.40 0.49 0.05 0.01

Corn (field, 

pop, seed)

0.025

(4)

15 1.91 0.87 1.07 0.12 0.03

35 1.63 0.75 0.92 0.10 0.02

1000 0.87 0.40 0.49 0.05 0.01

Corn 

(sweet)2 0.025

(6)

15 2.71 1.24 1.52 0.17 0.04

35 2.31 1.06 1.30 0.14 0.03

1000 1.24 0.57 0.70 0.08 0.02

Legume 

vegetables

0.025

(6)

15 2.47 1.13 1.39 0.15 0.03

35 2.11 0.97 1.19 0.13 0.03

1000 1.13 0.52 0.64 0.07 0.02

Rice (grain, 

straw)

0.025

(4)

15 1.71 0.78 0.96 0.11 0.02

35 1.46 0.67 0.82 0.09 0.02

1000 0.78 0.36 0.44 0.05 0.01

Root and 

tuber 

vegetables 

(except 

sugar beet)

0.025

(6)

15 2.59 1.19 1.45 0.16 0.04

35 2.21 1.01 1.24 0.14 0.03

1000 1.18 0.54 0.67 0.07 0.02

Sorghum 

(and other 

cerials)

0.025

(5)

15 1.82 0.83 1.02 0.11 0.03

35 1.56 0.71 0.87 0.10 0.02

1000 0.83 0.38 0.47 0.05 0.01

Tree nuts 0.025

(5)

15 2.01 0.92 1.13 0.13 0.03

35 1.72 0.79 0.97 0.11 0.02

1000 0.92 0.42 0.52 0.06 0.01

Wheat 0.025

(5)

15 1.61 0.74 0.91 0.10 0.02

35 1.38 0.63 0.77 0.09 0.02

1000 0.74 0.34 0.42 0.05 0.01 1 Use represents brassica vegetables, cucurbits, fruiting vegetables, leafy vegetables, soybeans, and sugar beets. 2 Use represents corn (sweet) and cotton.

Bolded value indicates that the chronic LOC (RQ > 1) for non-listed and listed mammalian species is exceeded. 

Chronic dietary-based RQs are based on effects associated with chemical concentrations in feed. 

Chronic dietary-based RQs are well below the non-listed and listed species LOCs for the

proposed new chemical uses of alpha-cypermethrin (RQs range from 0.01 to 0.31).Therefore 
-Page 54 of 126-

risks to mammalian species from chronic dietary exposure to alpha-cypermethrin is expected to 

be low. 

4.1.2.2. Birds

Acute RQs were not calculated for birds because only non-definitive acute and sub-acute toxicity 

endpoints are available. Alpha-cypermethrin is categorized as practically non-toxic to mallard 

duck and bobwhite quail on an acute and subacute oral and dietary basis. Acute risk to avian 

species is expected to be low. 

 

Chronic-based avian RQs are based on effects associated with chemical concentrations in feed. 

Chronic dietary-based RQs are well below the non-listed and listed species LOCs for the 

proposed new chemical uses of alpha-cypermethrin (RQs range from 0.02 to 0.62). Therefore 

chronic risks to avian species are expected to be low. 

4.1.2.3. Terrestrial Invertebrates 

Risk assessments are not conducted for terrestrial invertebrates at the screening-level at this time. 

Characterization of exposure relative to known toxicity endpoints for terrestrial invertebrates will 

be discussed in the Risk Description section.

4.1.2.4. Non-target Terrestrial Plants

Potential effects to riparian and upland vegetation are assessed deriving RQs from terrestrial 

plant seedling emergence and vegetative vigor EC25 and NOEAC endpoints. Based on the 

results of the submitted supplemental terrestrial plant toxicity tests for technical grade alphacypermethrin, there is the potential for effects to occur at proposed label rates. The maximum 

proposed single application rate for alpha-cypermethrin is 0.025 lbs a.i./A, which is nearly 

double the no effect concentration for dicot species (NOAEC = 0.0133 lbs a.i./A for oilseed rape

fresh weight). However, deficiencies in this study described in Section3.3.2.4 make it unsuitable 

for use in calculating RQs, so risks to terrestrial plants from the proposed new chemical uses 

remains uncertain. 

4.2. Risk Description

The results of risk estimation indicate that proposed uses of alpha-cypermethrin are likely to 

adversely affect non-listed fish and aquatic invertebrates on both an acute and chronic exposure 

basis, while risks to aquatic plants are low. In addition, the results indicate that proposed uses of 

alpha-cypermethrin have the potential to affect non-listed and listed terrestrial mammals. 

However, risks to terrestrial birds appear to be below the Agency’s levels of concern. 

4.2.1 Exposure to Aquatic Organisms
-Page 55 of 126-

The Tier II model Pesticide Root Zone Model (PRZM v3.12.2; May 12, 2005; Carousel et al., 

undated) linked with EXposure Analysis Modeling System (EXAMS v2.98.4.6; Apr. 25, 2005; 

Burns, 2004) via the PRZM/EXAMS model shell (PE v5.0, Nov. 15, 2006), i.e., 

PRZM/EXAMS) and the Tier I Rice Model (v1.0, May 8, 2007) were used to estimate screeninglevel exposure concentrations in aquatic environments. The PRZM model simulates pesticide 

movement and transformation on and across the agricultural field resulting from crop 

applications. The EXAMS model simulates pesticide concentrations in water due to loading via 

runoff, erosion, and spray drift, assuming a standard 1-ha pond, 2-m deep (20,000 m3) with no 

outlet that borders a 10-ha treated field. Simulations are for multiple (usually 30) years, from 

which the Agency estimates peak values that are expected to recur on average once every ten 

years, based on time series of daily estimated concentrations. 

The Tier I Rice Model was used to estimate screening-level exposure to alpha-cypermethrin that 

may occur in water bodies receiving release water from rice paddies that were treated with alphacypermethrin. This model was used to assess the proposed use on rice seed because the 

PRZM/EXAMS exposure models do not specifically address the unique rice growing 

environment and the model is approved for use in risk assessment. The model produces a single 

exposure value that represents a dissolved concentration within a rice paddy. This single value is 

used to approximate both acute and chronic exposures.

Model uncertainties are discussed in greater detail in Section 4.3.

4.2.2 Risks to Aquatic Animals

This risk assessment of alpha-cypermethrin shows that aquatic systems are potentially at risk 

from acute and chronic toxic exposure to this chemical. Evaluation of this risk to aquatic 

organisms was approached by dividing the aquatic system into two general compartments, the 

water column and the benthos. 

The first compartment, the water column, which is defined as the aquatic area between surface 

and the benthos (approximately 6 inches above the bottom) represents an area where organisms 

are free-swimming and can feed and breed at the surface, mid water and/or on the benthos 

(sediment). Direct pesticidal contact (e.g., gill lamella, ingestion, and integument) to these 

organisms is assumed to be from the surface water via drift and/or runoff. The toxicity 

assessment points are the acute LC50/ EC50 and chronic NOAEC that are generated through 

standard water column toxicity tests. 

The second aquatic compartment to be considered is the benthos, which is composed of 

sediments and an area 6 inches above the sediment (epibenthos). The benthos is composed of a 

diversity of aquatic invertebrates (e.g., insect larvae, crustaceans, mollusks) and species of fish 

(e.g., catfish, loachs), as well as certain critical life stages of organisms that reside in the water 

column; the benthos is also the initial breeding strata and nursery area for several species of fish, 

especially commercial species such as salmonids. The benthos can also be a source of food 
-Page 56 of 126-

items for several species of fish that are actively feeding on the organisms in the sediment and/or 

capturing organisms that are emerging from this area.

Aquatic Animals: Water Column Exposure

Several freshwater fish acute exposure studies were submitted to the Agency for racemic 

cypermethrin TGAI using the rainbow trout, all indicating that racemic cypermethrin is highly 

toxic to freshwater fish. Additionally, there is a study, also conducted with the rainbow trout,

that was conducted using the BASF 310 40 I product (a single ai formulation). This study 

resulted in an endpoint similar to the TGAI study (2.2 μg ai/L vs 0.39 μg ai/L), indicating that 

inert ingredients in the formulation do not enhance alpha-cypermethrin’s toxicity to fish. The 

most sensitive endpoint derived from the available alpha-cypermethrin studies was compared to 

the highest expected aquatic exposure values, and all are above the Agency’s levels of concern. 

Rainbow trout was the most sensitive species to alpha-cypermethrin among those studied, with 

an LC50 of 0.39 μg ai/L, and resulted in RQs that ranged from 0.15 to 1.38. These RQs are all 

greater than the non-listed species LOC. 

For estuarine/marine fish, the acute toxicity of technical grade racemic cypermethrin was 

evaluated in sheepshead minnow and Atlantic salmon, with 96-hour LC50 values of 0.95 μg a.i./L 

(MRID 00090075) and 4.3 μg a.i./L (MRID 41968212) respectively, indicating that the racemic 

cypermethrin TGAI is very highly toxic to estuarine/marine fish on an acute basis. The most 

sensitive endpoint derived from the available studies was compared to the highest expected 

aquatic exposure values, resulting in RQs above the Agency’s levels of concern (ranging from 

0.17 to 0.57). 

Although there is a definitive endpoint for chronic exposure to freshwater fish from a study with 

fathead minnow, a chronic exposure endpoint for estuarine/marine fish is not available. 

Therefore, an acute to chronic ratio (ACR) from the freshwater fish studies (~3X) was applied to 

the available acute estuarine/marine fish endpoint. Chronic RQs for freshwater and 

estuarine/marine fish are all well below the Agency’s level of concern for all proposed uses. 

Acute toxicity studies of technical grade racemic cypermethrin to freshwater invertebrates 

available include a 96-hour LC50 value for zeta-cypermethrin of 0.0036 μg a.i./L in Hyalella 

azteca (MRID 44423501), a 48-hour EC50 value for racemic cypermethrin of 0.42 μg a.i./L in 

in daphnid (MRID 44546031) and a 48-hour EC50 value for alpha-cypermethrin of 0.067 μg 

a.i./L om daphnids (MRID 47944208). Available information on BASF 310 40 I product (a 

single ai formulation of alpha-cypermethrin) indicates that the inert ingredients in the 

formulation do not enhance the toxicity of alpha-cypermethrin to freshwater invertebrates. For 

estuarine/marine invertebrates, the acute toxicity of technical grade cypermethrin was evaluated 

in shrimp, molluscs, and crustaceans. Based on these studies, alpha-cypermethrin can be 

categorized as very highly toxic on an acute basis to freshwater and estuarine/marine 

invertebrates. The most sensitive endpoint derived from the available studies was compared to 

the highest expected aquatic exposure values. Resulting RQs greatly exceed the Agency’s levels 

of concern for listed and non-listed species (ranging from 16.7 to 150, for freshwater species, and 
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from 12.6 to 113 for estuarine/marine species), indicating that freshwater and estuarine/marine 

invertebrates are at risk from exposure to alpha-cypermethrin. 

Although there is a definitive endpoint for chronic exposure to estuarine/marine invertebrates

from a study with the mysid shrimp, a chronic exposure endpoint for freshwater invertebrates is

not available. Therefore, an acute to chronic ratio (ACR) from the estuarine/marine invertebrate

studies (~2X) was applied to the available acute freshwater invertebrate endpoint. Chronic RQs 

for freshwater and estuarine/marine invertebrates range from 16.95 to 101.69 and from 12.8 to 

76.8, respectively. 

Aquatic Animals: Sediment Exposure

Risk estimates for benthic organisms show that alpha-cypermethrin poses sub-chronic and 

chronic risks to benthic organisms, based on sub-chronic and chronic RQs calculated using pore 

water EECs (Table 4.3). However, it should be noted that there are uncertainties regarding acute 

and chronic risk estimates for benthic organisms. First, the sub-chronic NOAEC value for pore 

water and the chronic NOAEC for pore water that were used to generate RQs were not 

determined in controlled laboratory studies. Rather, sub-chronic RQs for pore water were 

derived using a toxicity value estimated with the Equilibrium Partitioning Theory and the 

definition of the Koc, and the chronic RQs for pore water were generated based on the NOAEC 

value for the mysid shrimp (details provided in the Ecological Effects Characterization section 

and the previous section entitled, Aquatic Animals: Water Column Exposure). 

Second, the sub-chronic sediment toxicity value (in terms of whole sediment) used to estimate 

risk and to generate acute pore water and chronic pore water and sediment toxicity values was 

obtained from a study using a water-sediment system that was not at equilibrium; sediment 

concentrations decreased throughout the exposure period. Since residues that have reached 

equilibrium in the pore water are considered a greater source of toxic risk to benthic 

invertebrates (Di Toro et al., 1991), the studies presented in this assessment may underestimate 

sediment toxicity and equilibration should have occurred for at least one month prior to testing. 

If the exposure system had been at equilibrium, it is likely that the sub-chronic and chronic 

toxicity reference values for sediment and pore water would be lower, resulting in RQs that are 

higher than those derived in this assessment. However, even with these uncertainties, there are 

sub-chronic and chronic risks to benthic organisms for all modeled crop uses.

Based on the available sub-chronic toxicity data (the lowest sub-chronic NOAEC for benthic 

organisms; < 0.00182 μg a.i./L pore water and < 1.8 μg a.i./kg sediment), it is expected that a 21-

day pore water EEC of approximately 0.00181 μg a.i./L pore water would be sufficiently low to 

achieve sub-chronic RQ values for all benthic organisms that are less than the endangered 

species LOC (1.0). This means that the highest peak pore water and sediment EEC of 0.007 μg 

a.i./L pore water would have to be reduced by ~74.1%.

Based on the available chronic toxicity data (the lowest chronic NOAEC for benthic organisms 

of 0.000781 μg a.i./L pore water), it is expected that a 21-day pore water EEC of approximately 
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0.000780 ppb would be sufficiently low to achieve chronic RQ values for all benthic organisms 

that are less than the chronic LOC (1). This means that the highest 21-day pore water EEC of 

0.007 μg a.i./L pore would have to be reduced by ~88.8%.

Aquatic Animals: Mesocosm Studies

In addition to the aquatic animal guideline studies, the Agency received two mesocosm studies 

that provide information on the potential lingering effects of alpha-cypermethrin to water column 

and benthic dwelling invertebrates under more realistic environmental conditions. In the first 

study (MRID 48425009; supplemental), three stainless steel tanks were established for this 

mesocosm study. Two of the three tanks were treated with FASTAC (alpha-cypermethrin), at 

nominal concentrations of 1.8 and 2.4 μg/L; the third served as a negative control. Detected 

alpha-cypermethrin concentrations fell from 1.17 μg/L to 0.02 μg/L by day 16 with radioactively 

labeled benzyl (lesser nominal concentration), and from 1.24 μg/L (measured on day two) to 

0.04 μg/L on day 16 with the radioactively labeled cyclopropyl (higher nominal concentration). 

The study authors report the alpha-cypermethrin half-life in water as two to three days. In 

sediment, the radioactively labeled alpha-cypermethrin concentrations increased from day 0, 

with maximum concentrations of FASTAC recorded on day 16 (0.36 and 0.49 μg/core (assessed 

for the top cm of the sediment core) for benzyl and cyclopropyl labels, respectively). In situ

bioassays with Gammarus pulex revealed acute toxicity, with 100% mortality within 24 hours of 

first exposure through day 16 for cages suspended in the solution. For Gammarus in cages 

resting on the sediment surface, no organism survived for more than 24 hours for the first 27 

days following treatment, and 96 hour mortality exceeded control mortality through day 105.

In the second study (MRID 48425010; supplemental), three ponds (10m x 5m x 0.8m water 

depth), two treatment and one negative control, were established to study the fate and effects of 

FASTAC (100g/L emulsifiable concentrate) in the aquatic environment. The two treatment 

ponds were each treated at a rate of 15 g a.i./ha; one through direct incorporation, the other 

oversprayed. FASTAC residues in water and sediment, and toxicity to Gammarus pulex were 

assessed at various points throughout the study. Recovery of FASTAC from the treated ponds 

ranged from 0.36 to 0.03 μg/L and from 1.09 to 0.04 μg/L on days one and eight for the 

overspray and sub-surface applications respectively. Analysis of sediment samples determined 

FASTAC concentrations on day 16 as 5% of the total applied; falling to <2% of the 

concentration applied by day 47. FASTAC concentrations in the treatment ponds were acutely 

toxic to Gammarus through day 4, and lethality was observed for all animals within 24 hours of 

exposure. Acute toxicity was observed to a lesser degree through day 33. 

4.2.3 Risks to Aquatic Plants

Based on the available information on Lemna gibba and Skeletonema costatum, the proposed 

uses of alpha-cypermethrin do not exceed the Agency’s LOC for aquatic plant (1.0) for nonlisted 

or listed plants. While RQs were not calculated in the Risk Estimation section due to the lack of 

definitive IC50 values, there were effects noted in the studies. The lowest NOAEC among the 
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vascular and nonvascular studies is 1.39 μg ai/L for Lemna gibba (based on biomass and cell 

density). At that concentration, the RQ is less than 0.01 whereas the LOC is 1.0. In addition, 

supplemental studies using other aquatic nonvascular species indicate that they are less senstitive 

to alpha-cypermethrin than L. gibba. Therefore, potential risk to aquatic plants from the proposed 

uses of alpha-cypermethrin is expected to be low. 

4.2.4. Risks to Mammals

Dose-based acute mammalian RQs for all proposed uses result in listed species LOC 

exceedances, except for proposed uses on alfalfa and wheat. RQs that exceed the listed species 

LOC are for small and medium sized mammals exposed to alpha-cypermethrin on short grass 

only. In addition, dose-based chronic RQs for all proposed uses result in chronic non-listed and 

listed species LOC exceedances for small and medium sized mammals exposed to alphacypermethrin on short grass. In addition, some of the proposed uses result in chronic non-listead 

and listed species LOC exceedances for small and medium sized mammals exposed to alphacypermethrin on tall grass, broadleaf plants, and small insects. RQs are higher for smaller 

mammals due to an increased food ingestion rate associated with the higher metabolic rate of 

smaller mammals. However, chronic dietary-based RQs are well below the non-listed and listed 

species LOCs for the proposed new chemical uses of alpha-cypermethrin (RQs range from 0.01 

to 0.31).

4.2.5. Risk to Birds

Acute RQs were not calculated for birds because only non-definitive acute and sub-acute toxicity 

endpoints are available. No treatment-related sublethal effects were observed in either mallard 

duck or bobwhite quail studies at the highest concentrations tested. Therefore, alphacypermethrin is categorized as practically non-toxic to mallard duck and bobwhite quail on an 

acute and subacute oral and dietary basis. However, a supplemental oral toxicity study with the 

zebra finch indicate that alpha-cypermethrin may be slightly toxic to passerine bird species on an 

acute basis (LD50 = 1370 mg a.i./kg-bw). Due to study deficiencies described in Section 3.2.2.2 

it was not suitable for use in this risk assessment. Chronic dietary-based RQs, based on the 

available chronic toxicity data for the mallard duck and bobwhite quail, are well below the nonlisted and listed species LOCs for the proposed new chemical uses of alpha-cypermethrin (RQs 

range from 0.02 to 0.62).

The potential for direct mortality of nonlisted and listed birds (and to terrestrial-phase amphibian 

and reptiles for which birds serve as surrogates) from acute, subacute and chronic exposures of 

alpha-cypermethrin for all proposed uses is not expected. 

4.2.6. Potential Effects on Terrestrial Invertebrates

Although EFED does not quantitatively estimate risk to non-target terrestrial invertebrates, risks 

can be assessed qualitatively. This hazard assessment shows that alpha-cypermethrin exposure 

can be expected to result in acute toxicity to honey bees and is considered to be highly toxic on 
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both a contact (LD50 = 0.033 ug a.i./bee) and an oral basis (LD50 = 0.172 ug a.i./bee). In addition 

to the acute exposure data, the Agency received asupplemental semi-field study and a 

supplemental full field study that provide information on the effects of alpha-cypermethrin TEP 

to honey bees under more realistic environmental conditions for the hive. In the semi-field study 

(MRID 47944204; supplemental) honey bee (Apis mellifera) brood and whole colonies were 

exposed to alpha-cypermethrin by foliar application of the test material to full bloom lacy 

phacelia (Phacelia tanacetifolia) at a nominal rate of 0.03 lb ai/A (30 g ai/ha) in 400 L water/ha. 

Fields, consisting of three treatment groups (negative control, treated, and reference (ai: 

fenoxycarb) groups; each group contained three replicates), were covered with tunnel tents (12 x 

5 x 3.5 m; area covered 60 m2). The exposure phase was concluded 8 days after application and 

observations were continued up to 20 days post-application. Assessments of mortality, flight 

intensity, behavior of the bees, strength of the colonies, and development of the bee brood were 

conducted throughout pre- and post-application. Results of the study indicate that alphacypermethrin may result in significant effects on the mortality and early bee brood development 

at a rate of 0.03 lb ai/A (30 g ai/ha). Most of the adverse effects to honey bees observed were 

transient (e.g., mortality significantly elevated for one day following application but tailing off; 

and reduced foraging for two days after application but rebounding). However, the percentage of 

brood terminated before a successful hatch (ca. 65%) indicates that alpha-cypermethrin has 

potential to be of chronic concern to colony health. 

In the field study (MRID 47944206; supplemental), honey bee (Apis mellifera) brood and whole 

colonies were exposed to alpha-cypermethrin TEP by foliar application of the test material to full 

bloom lacy phacelia (Phacelia tanacetifolia) at a nominal rate of 0.03 lb ai/A (30 g ai/ha) in 400 

L water/ha. Sample locations included a treatment plot (2000 m2

) and a control plot (2400 m2). 

The exposure phase was concluded 28 days after application. Assessments of mortality, foraging 

activity (flight density), behavior of the bees, pollen collection, colony assessments (food stores, 

brood status, and hive populations), hive weight, and strength of the colonies were conducted 

throughout pre- and post-application. Results of the field study indicate that alpha-cypermethrin 

does not have an effect on mortality or brood development; however, statistical analyses were 

not conducted and colony replicate data was not available for analysis. 

In addition, results of an acute study with earthworms yielded a 48-hour contact LC50 value of 

26.09 ug a.i./cm2 for racemic cypermethrin applied to filter paper. Based on the data available at 

this time, acute and chronic risk to non-target insects and terrestrial invertebrates resulting from 

the proposed alpha-cypermethrin uses cannot be precluded.

Screening-level risk assessments do not typically evaluate risks to terrestrial invertebrates; 

however, toxicity information for beneficial insects is used to develop precautionary label 

language where necessary. Based on the available data, precautionary label language for bees is

necessary for end-use products with alpha-cypermethrin. The current label for BAS 310 40 I 

contains the following language: “This product is highly toxic to bees exposed to direct treatment 

or residues on blooming crops or weeds. DO NOT apply this product or allow it to drift to 

blooming crops if bees are visiting the treatment area”. 

4.2.7. Risk to Terrestrial Non-target Plants
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The acute toxicity of technical grade alpha-cypermethrin to terrestrial plants was evaluated for 

monocots (onion, Allium cepa; and oat, Avena sativa) and dicots (pea, Pisum sativum; oilseed 

rape, Brassica napus; carrot, Daucus carota; and sunflower, Helianthus annuus). The study 

(MRID 47944210) is classified as supplemental for qualitative use only because a definitive 

EC25 and NOAEC were not determined for the most sensitive monocot endpoint (onion fresh 

weight), in addition to other guideline deviations (e.g., study was conducted with TGAI instead 

of the recommended TEP). However, a definitive NOAEC value of 0.0133 lbs a.i/A was 

determined for the most sensitive dicot endpoint (oilseed rape fresh weight). This NOAEC value 

represents roughly half of the maximum single application rate for the proposed uses of alphacypermethrin and suggests that risks to plants may be possible. 

While there is uncertainty in the potential risks to plants because toxicity was observed in the 

supplemental study and the study, risk to nontarget terrestrial plants is not expected. It is 

presumed that additional data regarding the toxicity of alpha-cypermethrin to terrestrial plants 

would have minimal impact on the risk conclusions in this risk assessment.

4.3. Uncertainties and Data Gaps

As discussed in Appendix A, the registrat for BAS 310 40 I, BASF, submitted a minimal dataset 

to support their strategy to bridge data for the enriched enantiomeric mixture alpha-cypermethrin 

with the data previously submitted in support of the registration for the racemic mixture 

cypermethrin and the enriched enantiomeric mixture zeta-cypermethrin. As a result of the 

Agency’s acceptance of this strategy, ecological fate and ecotoxicity data gaps for alphacypermethrin will be fulfilled by the database for the previously registered cypermethrins (i.e., 

racemic and zeta-cypermethrin). Additional uncertainties and datagaps for alpha-cypermethrin 

are discussed below. 

4.3.1. Fate and Transport Uncertanties

The environmental fate database was bridged from the cypermethrins to alpha-cypermethrin. 

Data specific for alpha-cypermethrin suggest that the alpha enriched mixture may be less 

persistent than that of the cypermethrins (zeta and racemic cypermethrin), therefore 

environmental exposures may be over estimated. Appendix A outlines the specific data that 

were conducted using alpha-cypermethrin as the test material and where data were bridged from 

the racemic or zeta-cypermethrin. 

4.3.2. Effects Uncertainties

There are no chronic exposure toxicity data for freshwater invertebrates or estuarine/marine fish. 

Therefore, acute-to-chronic ratios (ACRs) based on the appropriate relationships were applied to 

each of the taxa (e.g., an ACR based on estuarine/marine invertebrates, for which there are both 

acute and chronic toxicity data, was applied to freshwater invertebrates). The ACR is considered 
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protective for the purpose of this risk assessment; however, the application of an ACR in the 

absence of actual data does introduce uncertainty to the risk assessment.

There are no chronic exposure toxicity data for the benthic invertebrate Hyalella azteca. 

Therefore, the chronic NOAEC value for the mysid shrimp (0.000781 μg a.i./L) served as a 

surrogate estimate of the chronic NOAEC for benthic organisms in units of μg a.i./L pore water. 

The mysid was selected as a surrogate because of similarities in life stages exposed during 

chronic toxicity tests for both species. In addition the LC50 value for the mysid shrimp and 

Hyalella azteca in 96-hour acute studies are very similar (LC50= 0.00475 μg a.i./L for mysid and 

LC50 = 0.0036 μg a.i./L) indicating that these species experience similar toxicity to 

cypermethrin. However, use of the mysid shrimp, a saltwater species, as a surrogate for H. 

azteca, a freshwater species, does introduce uncertainty to the risk assessment. 

5. Federally Threatened and Endangered (Listed) Species Concerns

Section 7 of the Endangered Species Act, 16 U.S.C. Section 1536(a)(2), requires all federal 

agencies to consult with the National Marine Fisheries Service (NMFS) for marine and 

anadromous listed species, and/or the United States Fish and Wildlife Service (USFWS) for 

listed wildlife and freshwater organisms, if they are proposing an "action" that may affect listed 

species or their designated critical habitat. Each federal agency is required under the Act to 

ensure that any action they authorize, fund, or carry out is not likely to jeopardize the continued 

existence of a listed species or result in the destruction or adverse modification of designated 

critical habitat. To jeopardize the continued existence of a listed species means "to engage in an 

action that reasonably would be expected, directly or indirectly, to reduce appreciably the 

likelihood of both the survival and recovery of a listed species in the wild by reducing the 

reproduction, numbers, or distribution of the species" (50 C.F.R. § 402.02).

To facilitate compliance with the requirements of the Endangered Species Act (subsection 

(a)(2)), the Office of Pesticide Programs has established procedures to evaluate whether a 

proposed registration action may directly or indirectly appreciably reduce the likelihood of both 

the survival and recovery of a listed species in the wild by reducing the reproduction, numbers, 

or distribution of any listed species (USEPA, 2004). After the Agency’s screening level risk 

assessment is conducted, if any of the Agency’s listed species’ LOCs are exceeded for either 

direct or indirect effects, an analysis is conducted to determine if any listed or candidate species 

may co-occur in the area of the proposed pesticide use or areas downstream or downwind that 

could be contaminated from drift or runoff/erosion. If listed or candidate species may be present 

in the proposed action area, further biological assessment is undertaken. The extent to which 

listed species may be at risk is considered, which then determines the need for the development 

of a more comprehensive consultation package, as required by the Endangered Species Act.

The federal action addressed herein is the proposed new registration of alpha-cypermethrin on 

agricultural use sites; it is expected that its use could occur nationwide.
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5.1. Action Area

For listed species assessment purposes, the action area is considered to be the area affected 

directly or indirectly by alpha-cypermethrin use and not merely the immediate area where alphacypermethrin is applied. At the initial baseline, the risk assessment considers broadly described 

taxonomic groups and conservatively assumes that listed species within those broad groups are 

co-located with the pesticide treatment area. This means that listed terrestrial plants and wildlife 

are assumed to be located on or adjacent to the treated site and listed aquatic organisms are 

assumed to be located in a surface water body adjacent to the treated site. The assessment also 

assumes that the listed species are located within an assumed area, which has the relatively 

highest potential exposure to the pesticide, and that exposures are likely to decrease with 

distance from the treatment area. Section 3.1 of this risk assessment presents the proposed 

pesticide use sites that are used to establish initial co-location of species with treatment areas.

5.2. Taxonomic Groups Potentially at Risk 

If the assumptions associated with the baseline action area result in RQs that are below the listed 

species LOCs, a "no effect" determination conclusion is made with respect to listed species in 

that taxa, and no further refinement of the action area is necessary. Furthermore, RQs below the 

listed species LOCs for a given taxonomic group indicate no concern for indirect effects on listed 

species that depend upon the taxonomic group for which the RQ was calculated. However, in 

situations where the screening assumptions lead to RQs in excess of the listed species LOCs for a 

given taxonomic group, a potential for a "may affect" conclusion exists and may be associated 

with direct effects on listed species belonging to that taxonomic group or may extend to indirect 

effects upon listed species that depend upon that taxonomic group as a resource. In such cases, 

additional information on the biology of listed species, the locations of these species, and the 

locations of use sites are considered to determine the extent to which screening assumptions 

regarding an action area apply to a particular listed organism. These subsequent refinement steps 

will consider how this information would impact the action area for a particular listed organism 

and potentially include areas of exposure that are downwind and downstream of the pesticide use 

site.

Assessment endpoints, exposure pathways, and the conceptual models addressing proposed new 

alpha-cypermethrin uses, and the associated exposure and effects analyses conducted for the 

alpha-cypermethrin baseline risk assessment are in Sections 2 to 3. The assessment endpoints 

used in the baseline risk assessment include those defined operationally as reduced survival and 

reproductive impairment for both aquatic and terrestrial animal species and survival, 

reproduction, and growth of aquatic and terrestrial plant species from both direct acute and 

chronic exposures. These assessment endpoints are intended to address the standard set forth in 

the Endangered Species Act requiring federal agencies to ensure that any action they authorize 

does not appreciably reduce the likelihood of both the survival and recovery of a listed species in 

the wild by reducing the reproduction, numbers, or distribution of the species. Risk estimates 

(RQs) which, integrating exposure and effects, are calculated for broad based taxonomic groups 

in the screening-level risk assessment presented in Section 4.
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Both acute endangered species and chronic risk LOCs are considered in the baseline risk 

assessment to identify direct and indirect effects to taxa of listed species. This section identifies 

direct effect concerns, by taxa that are triggered by exceeding endangered LOCs in the baseline

risk assessment, with an evaluation of the potential probability of individual effects for exposures 

that may occur at the established endangered species LOC. Data on exposure and effects 

collected under field and laboratory conditions are evaluated to make determinations on the 

predictive utility of the direct effect screening assessment findings to listed species. For alphacypermethrin, risk from chronic exposure is presumed for mammals. Potential acute risk to 

listed fish, aquatic-phase amphibians, and aquatic invertebrates is indicated based on exceedance 

of the LOC.

Table 5.1. Potential Effects to Federally Listed Taxa Associated with Direct or Indirect 

Effects from the Proposed New Uses of Alpha-Cypermethrin.

Listed Taxon Direct Effects Indirect Effectsa

Terrestrial and semi-aquatic plants - monocots No Yes

Terrestrial and semi-aquatic plants - dicots No Yes

Birds No Yes

Terrestrial-phase amphibians and reptiles No Yes

Mammals Yes Yes

Aquatic nonvascular plants No Yes

Aquatic vascular plants No Yes

Freshwater fish Yes Yes

Aquatic-phase amphibians Yes Yes

Freshwater crustaceans Yes Yes

Mollusks Yes Yes

Marine/estuarine fish Yes Yes

Marine/estuarine invertebrates Yes Yes a

until an endangered species assessment is complete, indirect effects to all species cannot be precluded
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5.2.1. Probit Dose-Response Analysis 

The Agency uses the probit dose-response relationship as a tool for providing additional 

information on the potential for acute direct effects to aquatic and terrestrial animals (USEPA, 

2004). As part of this evaluation, the acute RQ for listed species is presented in terms of the

chance of an individual event (i.e., mortality or immobilization) should exposure at the EEC 

actually occur for a species with sensitivity to alpha-cypermethrin on par with the acute toxicity 

endpoint selected for RQ calculation. To accomplish this interpretation, the Agency uses the 

slope of the dose-response relationship available from the toxicity study used to establish the 

acute toxicity measures of effect for each taxonomic group that is relevant to this assessment. 

The individual effects probability associated with the acute RQ is based on the mean estimate of 

the slope and an assumption of a probit dose-response relationship. In addition to a single effects 

probability estimate based on the mean, upper and lower estimates of the effects probability are 

also provided to account for variance in the slope, if available. Based on the available acute 

toxicity for alpha-cypermethrin, a summary of the probit dose-response analysis is provided in 

Table 5.2. If no dose response information is available to estimate a slope for this analysis, a 

default slope assumption of 4.5 (with lower and upper bounds of 2 to 9) (Urban and Cook, 1986) 

is used. 

Individual effect probabilities are calculated based on an Excel spreadsheet tool IECV1.1 

(Individual Effect Chance Model Version 1.1) developed by the U.S. EPA, OPP, Environmental 

Fate and Effects Division (June 22, 2004). The model allows for such calculations by entering 

the mean slope estimate (and the 95% confidence bounds of that estimate) as the slope parameter 

for the spreadsheet. The desired threshold for the probability of an individual effect is entered as 

the listed species LOC. In addition, the probability of an individual effect is also derived based 

on the calculated acute RQ, if available.
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Table 5.2. Summary of Alpha-Cypermethrin Probit Dose Response Analysis for Listed 

Species

Taxa (study type) Acute Effect

Slope (95% C.I.)

Chance of Individual 

Effect at Listed Species 

LOC (95% C.I.)

Chance of Individual 

Effect at Derived Acute 

RQ1,2,3 (95% C.I.)

Bird oral dose No mortality observed 1 in 2.9E+05

(1 in 44 to 1 in 8.86E+18)

Not calculated; no 

mortality observed

Bird dietary No mortality observed 1 in 2.9E+05

(1 in 44 to 1 in 8.86E+18)

Not calculated; no 

mortality observed

Mammal oral dose

Mortality

Slope = 3.5

(0.12 – 7.21)

1 in 4.3E+03

(1 in 2.21 to 1 in 

3.57E+12)

1 in 3.74E+02

(1 in 2.16 to 1 in 

2.09E+08)1

Freshwater Fish

Mortality 

Default Slope = 4.5 

(2 – 9)

1 in 4.18E+08

(1 in 2.16E+02 to 1 in 

1.75E+31)

1 in 1.38

(1 in 1.64 to 1 in 1.12)2

Freshwater invertebrates 

Mortality

Default Slope = 4.68

(2.35 – 7.02)

1 in 1.76E+09

(1 in 8.96E+02 to 1 in 

3.01E+19)

1 in 1

(1 in 1 to 1 in 1)3

1 Acute RQ for mammals = 0.16. 2 Acute RQ for freshwater Fish = 1.38. 3 Acute RQ for freshwater invertebrates = 150.

As shown in Table 5.2, the probability for acute direct effects (i.e., mortality) to individual listed 

fish (based on the most sensitive species, rainbow trout) and the highest derived RQ value is 1 in 

1.38. This reflects an average slope of 4.5. If the true dose response curve were steeper, the 

chance of an individual increases (e.g. slope of 9, chance is 1 in 1.12). The chance of an 

individual effect for aquatic invertebrates, based on the most sensitive species, Amphipod, is 1 in 

1. Based on this information, it is likely that the proposed use of alpha-cypermethrin will cause 

acute direct effects to listed fish and invertebrate species. 

5.2.2. Listed Species Occurrence Associated with Alpha-Cypermethrin Use

The goal of the co-location analysis is to determine whether sites of pesticide use are 

geographically associated with known locations of listed species [following the convention of the 

Services, the word ‘species’ in this assessment may apply to a ‘species’, ‘subspecies’, or an 

Evolutionary Significant Unit (ESU)]. At the screening level, this analysis is accomplished 

using the LOCATES database (version 2.10.3). The database uses location information for listed 

species at the county level and compares it to agricultural census data (from 2002) for crop 

production at the same county level of resolution. The product is a listing of Federally-listed 

species that are located in counties known to produce the crops upon which the pesticide will be 

used. A list of potentially directly affected species associated with the proposed new uses of 

alpha-cypermethrin is provided in Appendix F. Species potentially indirectly affected include 

all listed species. 

This preliminary analysis indicates that there is a potential for alpha-cypermethrin use to overlap 

with listed species and that a more refined assessment is warranted. The more refined 

assessment should involve clear delineation of the action area associated with proposed uses of 

alpha-cypermethrin and the best available information on the temporal and spatial co-location of 
-Page 67 of 126-

listed species with respect to the action area. This analysis has not been conducted for this 

assessment.
-Page 68 of 126-

6. References

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2006.

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Agency, Office of Pesticide Programs, Washington D.C.

6.1. Submitted Environmental Fate and Transport Studies

161-1 Hydrolysis

MRID Citation Reference

48425002 Dijk, A. (1993) Hydrolysis Determination of Carbon 14- Alphacypermethrin at 

Different pH Values. Project Number: 307383, AL/322/002. Unpublished study 

prepared by RCC Umweltchemie Ag. 95 p.

42620501 Clifton, J. (1992) Environmental Fate Studies: Hydrolysis Studies of 

Cypermethrin in Aqueous Buffered Solutions: Lab Project Number: 

191E1192E1: P-2771. Unpublished study prepared by FMC Corp. 77 p.

161-2 Photodegradation-water

MRID Citation Reference
-Page 70 of 126-

48425003 Concha, M.; Yan, Z.; Beigel, C. (2001) BAS 310 I (Alphacypermethrin): 

Aqueous Photolysis. Project Number: ENV/01/037, 903W, E/00/009. 

Unpublished study prepared by PTRL West, Inc. 171 p.

42395701 Estigoy, L.; Ruzo, L.; Shepler, K. (1992) Photodegradation of ?carbon 14-acid| 

and ?carbon 14-alcohol| Cypermethrin in Buffered Aqueous Solution at pH 7 by 

Natural Sunlight: Revised: Lab Project Number: 247/248W: 247/248W-1: 

191E1290E1. Unpub- lished study prepared by Pharmacology and Toxicology 

Research Research Lab (PTRL-West) and FMC Corp. 144 p.

161-3 Photodegradation-soil

MRID Citation Reference

42129001 Estigoy, L.; Ruzo, L.; Shepler, K. (1991) Photodegradation of Car- bon 14-Acid 

and Carbon 14-Alcohol Cypermethrin in/on Soil by Natural Sunlight: Lab 

Project Number: 249/250W: 191E1390E1: PC- 0159. Unpublished study 

prepared by PTRL West. 115 p

162-1 Aerobic soil metabolism

MRID Citation Reference

42156601 Ramsey, A. (1991) Environmental Fate Studies: Aerobic Soil Metabolism of 

Cypermethrin in a Sandy Loam Soil: Lab Project Number: 191E2190E1. 

Unpublished study prepared by FMC Corp. 99 p.

48425006 Gedik, L.; Keirs, D. (2001) [Carbon 14]- Alphacypermethrin (BAS 310 I): 

Degradation in Soil Under Aerobic Conditions. Project Number: ENV/01/012, 

399307, AL/620/013. Unpublished study prepared by Inveresk Research 

International. 119 p.

162-2 Anaerobic soil metabolism

MRID Citation Reference

42156602 Ramsey, A. (1991) Environmental Fate Studies: Anaerobic Soil Metabolism of 

Cypermethrin in a Sandy Loam Soil: Lab Project Number: 191E2590E1. 

Unpublished study prepared by FMC Corp. 93 p.

162-4 Aerobic aquatic metab.

MRID Citation Reference
-Page 71 of 126-

48425011 Mamouni, A. (1993) Fastac (Benzyl- Carbon 14): Degradation and Metabolism 

in Aquatic Systems. Project Number: 305864, AL/630/011. Unpublished study 

prepared by RCC Umweltchemie Ag. 166 p.

48425012 Voelkl, S. (1993) 14C- Alphacypermethrin (Cyclopropyl-1-14C): Degradation 

and Metabolism in Aquatic Systems. Project Number: 316326, AL/630/012. 

Unpublished study prepared by RCC Umweltchemie Ag. 128 p.

45920801 Curry, S. (2003) Aerobic Aquatic Metabolism of (Carbon 14)-ZetaCypermethrin: Lab Project Number: 194E2202E1: P-3592. Unpublished study 

prepared by FMC Corporation. 187 p.

162-3 Anaerobic aquatic metab.

MRID Citation Reference

44876105 Ramsey, A. (1998) Anaerobic Aquatic Metabolism of (carbon-14)-zetaCypermethrin: Lab Project Number: 194E2697E1: P-3329. Unpublished study 

prepared by FMC Corporation. 164 p.

163-1 Leach/adsorp/desorption

MRID Citation Reference

48425008 Hill, A. (1993) [Benzyl- Carbon 14] WL85875 (Fastac): Adsorption/Desorption 

in Three Soils. Project Number: SBTR/93/042, AL/620/011. Unpublished study 

prepared by Sittingbourne Research Center, Biotechnology and Tox. 47 p.

42129003 Froelich, L. (1991) Soil Mobility Studies: Adsorption/Desorption Studies of 

Cypermethrin: Lab Project Number: 191E3290E1. Unpub- lished study prepared 

by FMC Corp. 65 p.

42129002 Curry, S. (1991) Leaching of Carbon 14-Cypermethrin in Soil Follow- ing 

Aerobic Aging: Lab Project Number: 191E3190E1. Unpublished study prepared 

by FMC Corp. 97 p.

164-1 Terrestrial field dissipation

MRID Citation Reference

48425014 Forbes, S.; Knight, C. (1983) Analysis of Soil from UK for Residues of 

WL85871- Soil Persistence Trial- First Year. Project Number: SBGR/83/162, 

SRC18083, AL/790/006. Unpublished study prepared by Sittingbourne 
-Page 72 of 126-

Research Center, Biotechnology and Tox. 10 p.

48425015 Forbes, S.; Burden, A. (1983) Analysis of Soil from UK (Reculver) for Residues 

of WL85871 (Fastac)- Soil Persistence Trial-Second Year. Project Number: 

SBGR/84/005, SRC18083, AL/790/007. Unpublished study prepared by 

Sittingbourne Research Center, Biotechnology and Tox. 10 p.

48425016 Forbes, S.; Wales, G. (1985) Analysis of Soil from UK (Reculver) for Residues 

of Fastac (WL85871) - Soil Persistence Trial- Third Year. Project Number: 

SBGR/85/070, SRC42285, AL/790/008. Unpublished study prepared by 

Sittingbourne Research Center, Biotechnology and Tox. 13 p.

48425017 Bosio, P. (1983) Residues of WL 85871 and Metabolites in Soil from U.K. 

Treated with Fastac 1981/82 Trials. Project Number: BEGR/83/040, 

AL/790/009. Unpublished study prepared by Sittingbourne Research Center, 

Biotechnology and Tox. 9 p.

48425019 Forbes, S.; Wales, G. (1985) Analysis of Soil from UK (Hoath) for Residues of 

Fastac (WL85871)- Soil Persistence Trial- Third Year. Project Number: 

SBGR/85/072, SRC42285. Unpublished study prepared by Sittingbourne 

Research Center, Biotechnology and Tox. 14 p.

48425020 Forbes, S.; Mackay, C. (1983) Analysis of Soil from UK (Coates) for Residues 

of WL85871 (Fastac)- Soil Persistence Trial- First Year. Project Number: 

SBGR/83/418, SRC18083. Unpublished study prepared by Sittingbourne 

Research Center, Biotechnology and Tox. 10 p.

48425021 Forbes, S.; Wales, G. (1985) Analysis of Soil from UK (Coates) for Residues of 

Fastac (WL85871)- Soil Persistence Trial- Second Year. Project Number: 

SBGR/85/071, SRC42285, AL/790/013. Unpublished study prepared by 

Sittingbourne Research Center, Biotechnology and Tox. 12 p.

48425022 Coveney, P.; Forbes, S. (1986) Analysis of Soil from UK(Coates) for Residue of 

Fastac (WL85871)- Soil Persistence Trial- Third Year. Project Number: 

SBGR/86/201, SRC42286, AL/790/014. Unpublished study prepared by 

Sittingbourne Research Center, Biotechnology and Tox. 14 p.

42459601 Leppert, B. (1992) Ammo 2.5 EC Insecticide--Terrestrial Field Dissipation: Lab 

Project Number: 191E4191E1: RAN-0239. Unpublished study prepared by 

FMC Corporation. 182 p.

6.2. Submitted Ecotoxicity Studies

71-1 Avian Single Dose Oral Toxicity

MRID Citation Reference
-Page 73 of 126-

25769 2016140 Ross, D.B.; Cameron, D.M.; Roberts, N.L. (1977) The Acute Oral Toxicity 

(LD50) of PP 383 to the Mallard Duck. (Unpublished study received Dec 31, 

1979 under 10182-EX-19; prepared by Huntingdon Research Centre, 

submitted by ICI Americas, Inc., Wilmington, Del.; CDL:241598-G) 

90070 2016174 Roberts, N.L.; Fairley, C. (1980) The Acute Oral Toxicity (LDI50^) of 

Cypermethrin to the Mallard Duck: ICI 302/80305; CTL/8/994. (Unpublished 

study received Dec 30, 1981 under 10182-64; pre- pared by Huntington 

Research Centre, England, submitted by ICI Americas, Inc., Wilmington, 

Del.; CDL:070561-B) 

44546024 2016193 Johnson, A. (1998) Acute Toxicity (LD50) to Bobwhite Quail: 

Betacypermethrin: Lab Project Number: PWT 129: PWT 129/962076. 

Unpublished study prepared by Huntingdon Life Sciences Ltd. 38 p. 

92027002 Registrant 

Summary

Edwards, P. (1990) ICI Americas Inc. Phase 3 Summary of MRID 

00090070. The Acute Oral Toxicity (LD50) of Cypermethrin to the Mallard 

Duck: Report No. CTL/C/994; Study No. ICI/302/80305.: 10 p. 

71-2 Avian Dietary Toxicity

MRID Citation Reference

90071 2016164 Roberts, N.L.; Fairley, C.; Woodhouse, R.N. (1980) The Subacute Dietary 

Toxicity (LCI50^) of Cypermethrin to the Mallard Duck: ICI 330/WL/80812; 

55 1(a)/3. (Unpublished study received Dec 30, 1981 under 10182-64; 

prepared by Hungtindon Research Centre, England, submitted by ICI 

Americas, Inc., Wilmington, Del.; CDL: 070561-C) 

90072 2016165 Roberts, N.L.; Fairley, C.; Woodhouse, R.N. (1981) The Subacute Di- etary

Toxicity (LCI50^) of Cypermethrin to the Bobwhite Quail: ICI 331 WL/80811; 

5E.1(a)/4. (Unpublished study received Dec 30, 1981 under 10182-64; 

prepared by Huntingdon Research Centre, England, submitted by ICI 

Americas, Inc., Wilmington, Del.; CDL: 070561-D) 

44546025 2016184 Johnson, A. (1998) Dietary (LC50) to the Mallard Duck: Betacypermethrin: 

Lab Project Number: PWT 128: PWT 128/962075. Unpublished study 

prepared by Huntingdon Life Sciences Ltd. 40 p. 

44546026 2016185 Johnson, A. (1998) Dietary LC(50) to the Bobwhite Quail: Betacypermethrin: 

Lab Project Number: PWT 127: PWT 127/962074. Unpublished study 

prepared by Huntingdon Life Sciences Ltd. 40 p. 

92027003

Of

90072

Registrant 

Summary

Edwards, P. (1990) ICI Americas Inc. Phase 3 Summary of MRID 

00090072. The Subacute Dietary Toxicity (LC50) of Cypermethrin (PP383) 

to the Bobwhite Quail: Report No. ICI331WL/80811; Study No. 

ICI331WL/80811. Prepared by Huntingdon Research Centre 11 p. 

92027004

Of

90071

Registrant 

Summary

Edwards, P. (1990) ICI Americas Inc. Phase 3 Summary of MRID 

00090071. The Subacute Dietary Toxicity (LC50) of Cypermethrin (PP383) 

to the Mallard Duck: Report No. ISK/ICIWL284/79835. Prepared by 

Huntingdon Research Centre 11 p. 

71-4 Avian Reproduction

MRID Citation Reference
-Page 74 of 126-

90073 DER not 

locatedreviewed in 

1981

Roberts, N.L.; Fairley, C.; Chanter, D.O.; et al. (1981) The Effect of the 

Dietary Inclusion of Cypermentrin on Reproduction in the Mallard Duck: ICI 

341/8164; CTL/C/1091. (Unpublished study re- ceived Dec 30, 1981 under 

10182-64; prepared by Huntingdon Re- search Centre, England, submitted 

by ICI Americas, Inc., Wil- mington, Del.; CDL:070561-E) 

90074 2016144 Roberts, N.L.; Fairley, C.; Chanter, D.O.; et al. (1981) The Effect of Dietary 

Inclusion of Cypermethrin on Reproduction in the Bob- white Quail: ICI 

342/81341; CTL/C/1105. (Unpublished study re- ceived Dec 30, 1981 under 

10182-64; prepared by Huntingdon Re- search Centre, England, submitted 

by ICI Americas, Inc., Wil- mington, Del.; CDL:070561-F) 

92027005 Registrant 

Summary

Edwards, P. (1990) ICI Americas Inc. Phase 3 Summary of MRID 

00090074. The Effect of Dietary Inclusion of Cypermethrin on Reproduction 

in Bobwhite Quail: Report No. CTL/C/1105; Study No.: ICI342/81341.: 15 p. 

92027006 Registrant 

Summary

Edwards, P. (1990) ICI Americas Inc. Phase 3 Summary of MRID 

00090073. The Effect of the Dietary Inclusion of Cypermethrin on 

Reproduction in the Mallard Duck: Report No. CTL/C/1091; Study No.: 

ICI341/8164.: 15 p. 

72-1 Acute Toxicity to Freshwater Fish

MRID Citation Reference

62791 See 65812 Hill, R.W.; Maddock, B.G.; Harland, B.J. (1980) Determination of the Acute 

Toxicity of Cypermethrin (PP 383) to Bluegill Sunfish (Lepomis 

macrochirus): BL/B/2011. (Unpublished study received Dec 5, 1980 under 

279-EX-86; prepared by Imperial Chemical Industries, Ltd., England, 

submitted by FMC Corp., Philadelphia, Pa.; CDL:243861-AE) 

62792 DER not 

locatedReviewed in 

1982

Hill, R.W.; Maddock, B.G.; Harland, B.J. (1980) Determination of the Acute 

Toxicity of Cypermethrin (PP 383) to Rainbow Trout (Salmo gairdneri): 

BL/B/2006. (Unpublished study received Dec 5, 1980 under 279-EX-86; 

prepared by Imperial Chemical Industries, Ltd., England, submitted by FMC 

Corp., Philadelphia, Pa.; CDL:243861-AF) 

65812 2016475 Hill, R.W.; Maddock, B.G.; Harland, B.J. (1980) Determination of the Acute 

Toxicity of Cypermethrin (PP 383) to Bluegill Sunfish (Lepomis 

macrochirus): BL/B/2011. (Unpublished study received Dec 29, 1980 under 

10182-EX-19; prepared by Imperial Chemical Industries, Ltd., England, 

submitted by ICI Americas, Inc., Wilmington, Del.; CDL:244017-D) 

65813 DER not 

locatedreviewed in 

1981

Hill, R.W.; Maddock, B.G.; Harland, B.J. (1980) Determination of the Acute 

Toxicity of GFU 061, a 36% w/v Formulation of Cypermethrin to Rainbow 

Trout (Salmo gairdneri): BL/B/2016. (Unpublished study received Dec 29, 

1980 under 10182-EX-19; prepared by Imperial Chemical Industries, Ltd., 

England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:244017-E) 

65814 DER not 

l.ocated

Hill, R.W.; Maddock, B.G.; Harland, B.J. (1980) Determination of the Acute 

Toxicity of GFU 061, a 36% w/v Formulation of Cypermethrin to Bluegill 

Sunfish (Lepomis macrochirus): BL/B/ 2017. (Unpublished study received 

Dec 29, 1980 under 10182-EX- 19; prepared by Imperial Chemical 

Industries, Ltd., England, submitted by ICI Americas, Inc., Wilmington, Del.; 

CDL:244017-F) 
-Page 75 of 126-

65816 Permethrin 

study

Hill, R.W.; Young, B.E. (1978) The Acute Toxicity of Permethrin Acid and 

3-Phenoxy Benzyl Alcohol to Rainbow Trout (Salmo gairdneri): 

BL/B/1918. (Unpublished study received Dec 29, 1980 under 10182-EX-19; 

prepared by Imperial Chemical Industries, Ltd., England, submitted by ICI 

Americas, Inc., Wilmington, Del.; CDL:244017-J) 

88947 2016176

2079552 = 

contract draft

Hill, R.W.; Maddock, B.G.; Comber, M.H.I. (1981) Cypermethrin: 

Determination of the Acute Toxicity of Formulation GFU 070 to Rainbow 

Trout (?~Salmo gairdneri~?): BL/B/2093. (Unpublished study received Dec 

30, 1981 under 10182-64; prepared by Imperial Chemical Industries, Ltd., 

submitted by ICI Americas, Inc., Wilmington, Del.; CDL:070558-C) 

88948 2016177 Hill, R.W.; Maddock, B.G.; Comber, M.H.I. (1981) Cypermethrin. 

Determination of the Acute Toxicity of Formulation GFU 070 to Bluegill 

Sunfish (?~Lepomis macrochirus~?): BL/B/2099. (Unpub- lished study 

received Dec 30, 1981 under 10182-64; prepared by Imperial Chemical 

Industries, Ltd., submitted by ICI Americas, Inc., Wilmington, Del.; 

CDL:070558-D) 

89036 DER not 

located

Reiff, B.; Pearson, N.; Rees, H.J.; et al. (1978) The Effect of Suspended 

Solids on the Toxicity of WL 43467 to Rainbow Trout (?~Salmo gairdneri~?): 

Group Research Report TLGR.0007.78. (Un- published study received Dec 

30, 1981 under 10182-64; prepared by Shell Research, Ltd., England, 

submitted by ICI Americas, Inc., Wilmington, Del.; CDL:070562-A) 

89037 2016146 Hill, R.W.; Young, B.E.; Comber, M.H.I. (1981) Determination of the Acute 

Toxicity of 3-Phenoxy Benzoic Acid to Rainbow Trout (?~Salmo 

gairdneri~?): Brixham Report No. Bl/B/2038. (Unpub- lished study received 

Dec 30, 1981 under 10182-64; prepared by Imperial Chemical Industries, 

Ltd., England, submitted by ICI Americas, Inc., Wilmington, Del.; 

CDL:070562-B) 

89038 2016147 Hill, R.W.; Young, B.E.; Comber, M.H.I. (1981) Determination of the Acute 

Toxicity of 3-Phenoxy Benzoic Acid to Bluegill Sunfish (?~Lepomis 

macrochirus~?): Brixham Report No. BL/B/2086. (Un- published study 

received Dec 30, 1981 under 10182-64; prepared by Imperial Chemical 

Industries, Ltd., England, submitted by ICI Americas, Inc., Wilmington, Del.; 

CDL:070562-C) 

41068002 Open lit Coats, J.; O'Donnell-Jeffery, N. (1979) Toxicity of four synthetic pyrethroid 

insecticides to rainbow trout. Bulletin of Enviro- mental Contamination 

and Toxicology 23:250-255.

41068003 Open lit McLeese, D.; Metcalfe, C.; Zitko, V. (1980) Lethality of permethrin, 

cypermethrin and fenvalerate to salmon, lobster and shrimp. Bulletin of 

Environmental Contamination and Toxicology 25:950-955.

41068004 Open lit Stephenson, R. (1981) Aquatic toxicology of cypermethrin: I acute 

toxicology to some freshwater fish and invertebrates in labora- tory tests. 

Aquatic Toxicology 2:175-185.

41968208 2016167 Overman, M.; Barron, M.; Vaishnav, D. (1990) Cypermethrin-S (FMC 

56701): Acute Toxicity to Rainbow Trout (Oncorhynchus mykiss) Under 

Flow-through Test Conditions: Lab Project Number: 3903026- 0700-3140. 

Unpublished study prepared by Environmental Science and Engineering, 

Inc. 48 p. 
-Page 76 of 126-

41968209 2016173 Vaishnav, D.; Yurk, J. (1990) Cypermethrin (FMC 45806): Acute Toxi- city to 

Rainbow Trout (Oncorhynchus mykiss) Under Flow-through Test 

Conditions: Lab Project Number: 3903026-0750-3140. Unpub- lished study 

prepared by Environmental Science and Engineering, Inc. 46 p. 

44546027 2016194 Sousa, J. (1998) (Carbon 14)-Cypermethrin--Acute Toxicity to Rainbow 

Trout (Oncorhynchus mykiss) Under Flow-Through Conditions: Final Report: 

Lab Project Number: 97-11-7166: 12442.1096.6223.108. Unpublished study 

prepared by Springborn Labs., Inc. 91 p. 

44546028 2016196 Sousa, J. (1998) Cypermethrin Technical--Acute Toxicity to Rainbow Trout 

(Oncorhynchus mykiss) Under Flow-Through Conditions: Final Report: Lab 

Project Number: 98-1-7213: 12442.1096.6222.108. Unpublished study 

prepared by Springborn Labs., Inc. 78 p. 

44546029 2016186 Sousa, J. (1998) (Carbon 14)(Beta)-Cypermethrin--Acute Toxicity to Bluegill 

Sunfish (Lepomis macrochirus) Under Flow-Through Conditions: Final 

Report: Lab Project Number: 97-12-7177: 12442.1096.6225.105. 

Unpublished study prepared by Springborn Labs., Inc. 91 p. 

44546030 2016187 Sousa, J. (1998) Cypermethrin Technical--Acute Toxicity to Bluegill Sunfish 

(Lepomis macrochirus) Under Flow-Through Conditions: Final Report: Lab 

Project Number: 97-12-7195: 12442.1096.6224.105. Unpublished study 

prepared by Springborn Labs., Inc. 76 p. 

92027007 Registrant 

summary

Adams, D. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00065812.

Cypermethrin Technical PP383: Determination of the Acute Toxicity to 

Bluegill Sunfish (Lepomis macrochirus): Report No. BL/B/2011; Study No.: 

F342/D. Prepared by ICI Brixham Laboratory 13 p. 

92027008 Registrant 

Summary

Adams, D. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00089038. 

3-Phenoxybenzoic Acid: Determination of the Acute Toxicity to Bluegill 

Sunfish (Lepomis macrochirus): Report No. BL/2086; Study No.: G145/D.: 

12 p 

92027009 Registrant 

Summary

Adams, D. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00088948.

Cypermethrin (PP383): Determination of the Acute Toxicity of a 2lb/US 

gallon formulation to Bluegill Sunfish (Lepomis macrochirus): Report No. 

BL/B/2099; Study No.: G244/C. Prepared by ICI Brixham Laboratory 13 p. 

92027010 Registrant 

Summary

Hill, R. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00089037. 3-

Phenoxybenzoic Acid: Determination of the Acute Toxicity of the Active 

Ingredient (99% Purity w/w) to Rainbow Trout (Salmo gairdneri): Report No. 

BL/B/2038; Study No.: G 145/C. Prepared by ICI Brixham Laboratory 12 p. 

92027011 Registrant 

Summary

Treacy, C. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00062792.

Cypermethrin (PP383): Determination of the Acute Toxicity of Active 

Ingredient (91. 5% purity) to Rainbow Trout (Salmo gairdneri) Report No. 

BL/B/2006; Study No.: F342/B.: 12 p. 

92027012 Registrant 

Summary

Coleman, C. (1990) ICI Americas Inc. Phase 3 Summary of MRID 

00088947. Cypermethrin: Determination of the Acute Toxicity of a 25% w/w 

Formulation to Rainbow Trout (Salbo gairdneri): Report No. BL/B/2093; 

Study No.: G244/B.: 12 p. 

92027013 Registrant 

Summary

Treacy, C. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00065813. 

Cypermethrin: Determination of the Acute Toxicity of Formulation GFU 061 

to Rainbow Trout (Salmo gairdneri): Report No. BL/B/2016; S No. F617/B.: 
-Page 77 of 126-

12 p. 

72-2 Acute Toxicity to Freshwater Invertebrates

MRID Citation Reference

62793 Or

92027014

2016162 Edwards, P.J.; Brown, S.M.; Sapiets, A.S. (1980) Cypermethrin (PP383): 

Toxicity of Technical and Formulated Material to First Instar Daphnia 

magna: Report Series RJ 0110B. (Unpublished study received Dec 5, 1980 

under 279-EX-86; prepared by Imperial Chemical Industries, Ltd., England, 

submitted by FMC Corp., Philadelphia, Pa.; CDL:243861-AG) 

65815 See 62793 Edwards, P.J.; Brown, S.M.; Sapiets, A.S.; et al. (1980) Cypermethrin 

(PP383): Toxicity of Technical and Formulated Material to First Instar 

Daphnia magna: Report Series RJ 0110B. (Unpublished study received 

Dec 29, 1980 under 10182-EX-19; prepared by Imperial Chemical 

Industries, Ltd., England, submitted by ICI Americas, Inc., Wilmington, Del.; 

CDL:244017-H) 

65817 Permethrin 

study

Getty, C.; Wilkinson, W.; Davies, P.J.; et al. (1978) Permethrin Acid and 

3-Phenoxybenzyl Alcohol: Toxicity to First Instar Daphnia magna: Report 

Series RJ 0042B. (Unpublished study received Dec 29, 1980 under 10182-

EX-19; prepared by Imperial Chemical Industries, Ltd., submitted by ICI 

Americas, Inc., Wilmington, Del.; CDL:244017-K) 

88949 DER not 

located

Edwards, P.J.; Brown, S.M.; Swaine, H.; et al. (1981) Cypermethrin 

(PP383): Toxicity of Formulation GFU070 to First Instar ?~Daphnia 

magna~?: Report Series RJ 0199B. (Unpublished study received Dec 30, 

1981 under 10182-64; prepared by Imperial Chemical Industries, Ltd., 

England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:070558-E) 

89040 2016162 Edwards, P.J.; Brown, S.M.; Swaine, H.; et al. (1980) Cypermethrin 

(PP383): Toxicity of Formulation GFU061 to First Instar~Daphnia~ 

?~magna~?: Report Series RJ 0149B. (Unpublished study received Dec 

30, 1981 under 10182-64; prepared by Imperial Chemical In- dustries, Ltd., 

submitted by ICI Americas, Inc., Wilmington, Del.; CDL:070562-E) 

89041 2016150 Stephenson, R.R.; Bennett, D.; Francis, W.H.P.; et al. (1980) The Acute 

Toxicity of Cypermethrin (WL 43467) to the Freshwater Shrimp 

(?~Gammarus pulex~?) and Larvae of the Mayfly, (?~Cloeon~ 

?~dipterum~?), in Continuous-flow Tests: Group Research Report 

TLGR.80.079. (Unpublished study received Dec 30, 1981 under 10182-64; 

prepared by Shell Research, Ltd., England, submitted by ICI Americas, Inc., 

Wilmington, Del.; CDL:070562-G) 

89042 DER nor 

locatedreviewed in 

1982-core

Jaber, M.J.; Hawk, R.E. (1981) The Acute Toxicity of Cypermethrin to 

Crayfish (?~Orconectes sp~?.): Report Series TMUE0008/B. (Unpublished 

study received Dec 30, 1981 under 10182-64; sub- mitted by ICI Americas, 

Inc., Wilmington, Del.; CDL:070562-H) 

89046 2016153 Edwards, P.J.; Brown, S.M.; Swaine, H.; et al. (1980) 3-Phenoxy- benzoic 

Acid: Toxicity to First Instar~Daphnia magna~?:Report Series RJ 0148B. 

(Unpublished study received Dec 30, 1981 under 10182-64; prepared by 

Imperial Chemical Industries, Ltd., submitted by ICI Americas, Inc., 

Wilmington, Del.; CDL:070562-L) 
-Page 78 of 126-

89048 2016155 Edwards, P.J.; Brown, S.M.; Hamer, M.J.; et al. (1980) Cyper- methrin: 

Acute Toxicity to the Mayfly, Baetis rhodani: Report Series RJ 0173B. 

(Unpublished study received Dec 30, 1981 under 10182-64; prepared by 

Imperial Chemical Industries, Ltd., sub- mitted by ICI Americas, Inc., 

Wilmington, Del.; CDL:070562-N) 

140833 2016149 Stephenson, R.R.; Sherwood, C.M.; Bennett, D.; et al. (1980) The Acute 

Toxicity of WL 43467 to Some Freshwater Invertebrates in Static Water 

Tests: Group Research Report TLGR.80.040. (Un- published study 

received Dec 30, 1981 under 10182-64; prepared by Shell Research, Ltd., 

England, submitted by ICI Americas, Inc., Wilmington, Del.; CDL:070562-F) 

41068004 Open lit Stephenson, R. (1981) Aquatic toxicology of cypermethrin: I acute 

toxicology to some freshwater fish and invertebrates in labora- tory tests. 

Aquatic Toxicology 2:175-185.

41968210 2016168 Ward, T.; Boeri, R. et al. (1991) Acute Toxicity of FMC 56701 Tech- nical 

and Cypermethrin Technical to the Daphnid, Daphnia magna: Lab Project 

Number: 90186-FMC: A90-3310. Unpublished study prepared by Resource 

Analysts, Inc. 46 p. 

43293501 DER not 

locatedcontract draft 

available

Wheat, J.; Evans, J. (1994) Zetacypermethrin Technical and Cypermethrin 

Technical: Comparative Acute Toxicity to the Water Flea (Daphnia magna), 

under Flow-Through Test Conditions: Lab Project Number: J9210001B: 

A92/3636. Unpublished study prepared by Toxikon Environmental 

Sciences. 76 p. 

44074401 DER not 

located

Rapley, J.; Hamer, M. (1996) Cypermethrin: Toxicity to Chironomus riparius 

and Hyalella azteca: Lab Project Number: RC0002: 95JH082. Unpublished 

study prepared by Zeneca Agrochemicals. 15 p. 

44074402 2063977 Gentle, W.; Goggin, U.; Rapley, J.; et al. (1996) Cypermethrin: Toxicity to 

Chironomus tentans in Sediment-Water Systems: Lab Project Number: 

RC0001: 96JH007. Unpublished study prepared by Zeneca Agrochemicals. 

31 p. 

44074406 2063978 Farrelly, E.; Gentle, W.; Goggin, U.; et al. (1996) Cypermethrin: Toxicity to 

Hyalella azteca in Sediment-Water Systems: Lab Project Number: RC0006: 

95JH228. Unpublished study prepared by Zeneca Agrochemicals. 30 p. 

44423501 DER not 

located

Hamer, M. (1997) Cypermethrin: Acute Toxicity of Short-Term Exposures to 

Hyalella Azteca: Lab Project Number: TMJ3904B. Unpublished study 

prepared by Zeneca Agrochemicals. 10 p. 

44546031 2016188 Putt, A. (1998) (Carbon 14)(Beta)Cypermethrin--Acute Toxicity to Daphnids 

(Daphnia magna) Under Flow-Through Conditions: Final Report: Lab 

Project Number: 97-9-7079: 12442.1096.6227.115. Unpublished study 

prepared by Springborn Labs., Inc. 95 p. 

44546032 2016189 Putt, A. (1998) Cypermethrin Technical--Acute Toxicity to Daphnids 

(Daphnia magna) Under Flow-Through Conditions: Final Report: Lab 

Project Number: 97-11-7138: 12442.1096.6226.115. Unpublished study 

prepared by Springborn Labs., Inc. 74 p. 

92027014 Registrant 

Summary

Hamer, M. (1990) ICI Americas Inc. Phase 3 Summary of MRID 

00062793. Cypermethrin (PP383): Toxicity of Technical and Formulated 

Material to First Instar Daphna (sic) magna: Report No.: RJ011OB; Study 

No.: PP383/CN/01. Prepared by ICI Agrochemicals, Jealott's Hill Research 
-Page 79 of 126-

Station. 17 p. 

92027015 Registrant 

Summary

Hamer, M. (1990) ICI Americas Inc. Phase 3 Summary of MRID 

00089046. 3-Phenoxybenzoic Acid: Toxicity to First Instar Daphna (sic) 

magna: Report No.: RJ0148B; Study No.: PP383/CN/03. Prepared by ICI 

Agrochemicals, Jealott's Hill Research Station. 14 p. 

92027016 Registrant 

Summary

Hamer, M. (1990) ICI Americas Inc. Phase 3 Summary of MRID 

00065817. Permethrin Acid and 3-Phenoxybenzyl Alcohol: Toxicity to First 

Instar Daphnia Magna: Report No.: RJ0042B; Study No.: PP557/CN/01. 

Prepared by ICI Agrochemicals Jealott's Hill Research Station 18 p. 

92027017 Registrant 

Summary

Hamer, M. (1990) ICI Americas Inc. Phase 3 Summary of MRID 

00152739. 3 Phenoxybenzoic Acid: Toxicity to First Instar Daphnia magna 

(II): Report No.: RJ0318B; PP563/CN/01. Prepared by ICI Agrochemicals 

Jealott's Hill Research Station 14 p. 

31225 DER not 

located

Leblanc, G.A. (1976) Acute Toxicity of FMC-30980 to Daphnia magna: ACT 

011.12. (Unpublished study received Sep 28, 1976 under 279-EX-63; 

prepared by EG&G, Bionomics, submitted by FMC Corp., Philadelphia, Pa.; 

CDL:227762-E) 

152739 2016175 Everett, C.J., M.J. Hamer and I.R. Hill (1983) 3-Phenoxybenzoic Acid: 

Toxicity to First Instar Daphnia magna (II). Report Series RJ 0318B. 

Prepared and Submitted by ICI Plant Protection Division, Bracknell, 

Berkshire, England. EPA MRID No. 152739.

72-3 Acute Toxicity to Estuarine/Marine Organisms

MRID Citation Reference

89043 2016151

2016161

Jaber, M.J.; Hawk, R.E. (1981) The Acute Toxicity of Cypermethrin to Pink 

Shrimp (Penaeus duorarum): Report Series TMUE004/B. (Unpublished 

study received Dec 30, 1981 under 10182-64; sub- mitted by ICI Americas, 

Inc., Wilmington, Del.; CDL:070562-I) 

89044 2016166 Jaber, M.J.; Hawk, R.E. (1981) The Acute and Chronic Toxicity of 

Cypermethrin to Mysid Shrimp (?~Mysidopsis bahia~?): Report Series 

TMUE0005/B. (Unpublished study received Dec 30, 1981 under 10182-64; 

submitted by ICI Americas, Inc., Wilmington, Del.; CDL:070562-J) 

89045 2016152 Jaber, M.J.; Hawk, R.E. (1981) The Acute Toxicity of Cypermethrin to 

Fiddler Crabs (?~Uca pugilator~?): Report Series TMUE0003/B. 

(Unpublished study received Dec 30, 1981 under 10182-64; sub- mitted by 

ICI Americas, Inc., Wilmington, Del.; CDL:070562-K) 

89049 2016154 Jaber, M.J.; Hawk, R.E. (1981) The Acute Toxicity of Cypermethrin to 

Eastern Oysters (Crassostrea virginica): Report Series TMUE0009/B. 

(Unpublished study received Dec 30, 1981 under 10182-64; submitted by 

ICI Americas, Inc., Wilmington, Del.; CDL:070562-O) 

89050 2016143 Hill, R.W.; Thompson, R.S.; Comber, M.H.I. (1981) Investigation of the 

Acute Toxicity of PP 383 to Larvae of the Pacific Oyster (Crassostrea 

gigas): Brixham Report No. BL/B/2088. (Unpub- lished study received Dec 

30, 1981 under 10182-64; prepared by Imperial Chemical Industries, Ltd., 

England, submitted by ICI Americas, Inc.; Wilmington, Del.; CDL:070562-P) 
-Page 80 of 126-

90075 DER not 

located

Jaber, M.J.; Hawk, R.E. (1981) The Acute Toxicity of Cypermethrin to 

Sheepshead Minnows (?~Cyprinodon variegatus?~): Report Series 

TMUE0002/B. (Unpublished study received Dec 30, 1981 under 10182-64; 

submitted by ICI Americas, Inc., Wilmington, Del.; CDL:079561-G) 

41968211 2016171 Overman, M.A., M.G. Barron and D.D. Vaishnav (1990) Cypermethrin-S

(FMC 56701): Acute Toxicity to Sheepshead Minnow (Cyprinodon 

variegates) under Flow-Through Test Conditions. Laboratory Project No. 

3903026-0600-3140. Study Performed by Environmental Science and 

Engineering, Inc., Gainesville, FL. Submitted by FMC Corporation, 

Philadelphia, PA. EPA MRID No. 31968211.

41968212 2016170 Chandler, A. (1990) FMC 45806: Acute Toxicity to Sheepshead Minnow 

(Cyprinodon variegatus) Under Flow-through Test Conditions: Lab Project 

Number: 3903026-0350-3140. Unpublished study prepared by 

Environmental Science and Engineering(ESE), Inc. 43 p. 

41968213 2016169 Ward, T.; Boeri, R. (1991) Acute Toxicity of FMC 56701 Technical and 

Cypermethrin Technical to the Mysid, Mysidopsis bahia: Lab Project 

Number: 90187-FMC: A90-3309. Unpublished study prepared by Resource 

Analysts, Inc. 52 p. 

42364701 Registrant 

rebuttal

Anon. (1992) Response to the EPA's Review of MRID 41968212

Cypermethrin: Acute Toxicity to Sheepshead Minnows Under Flow-Through 

Test Conditions: Unpublished study prepared by FMC Corp. 8 p. 

44546033 2016195 Dionne, E. (1998) Cypermethrin Technical--Acute Toxicity to Sheepshead 

Minnow (Cyprinodon variegatus) Under Flow-Through Conditions: Final 

Report: Lab Project Number: 97-12-7197: 12442.1096.6230.505. 

Unpublished study prepared by Springborn Labs., Inc. 75 p. 

44546034 2016187 Sousa, J. (1998) (Carbon 14)(Beta)-Cypermethrin--Chronic Toxicity to 

Sheepshead Minnow (Cyprinodon variegatus) Under Flow-Through 

Conditions: Final Report: Lab Project Number: 97-1-7212: 

12442.1096.6231.505. Unpublished study prepared by Springborn Labs., 

Inc. 91 p. 

44561209 2016191 Putt, A. (1998) (Carbon-14) Beta-Cypermethrin--Acute Toxicity to Mysids 

(Mysidopsis bahia) Under Flow-Through Conditions: Final Report: Lab 

Project Number: 97-11-7153: 12442.1096.6229.515. Unpublished study 

prepared by Springborn Laboratories, Inc. 79 p. 

44561210 2016190 Putt, A. (1998) Cypermethrin Technical--Acute Toxicity to Mysids 

(Mysidopsis bahia) Under Flow-through Conditions: Final Report: Lab 

Project Number: 98-1-7224: 12442.1096.6228.815. Unpublished study 

prepared by Springborn laboratories, Inc. 76 p. 

92027018 Registrant 

Summary

Royal, P. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00090075. 

Cypermethrin: Acute Toxicity of Technical Material for Sheepshead Minnow 

(Cyprinodon variegatus): Report No.: TMUE 0002/B.: 15 p. 

92027019 Registrant 

Summary

Royal, P. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00089049. 

Cypermethrin: The Acute Toxicity to Eastern Oysters (Crassostrea 

virginica): Report No. TMUE 0009/B. Prepared by Springborn Laboratories, 

Inc. 13 p. 

92027020 Registrant 

Summary

Royal, P. (1990) Ici Americas Inc. Phase 3 Summary of MRID 00089043. 

Cypermethrin: Determination of the Acute Toxicity of Technical Material to 
-Page 81 of 126-

Pink Shrimp (Penaeus duorarum): Report No. TMUE 0004/B. Prepared by 

Springborn Laboratories, Inc. 15 p. 

92027021 2016166 

Registrant 

Summary

Royal, P. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00089044. 

Cypermethrin: Determination of Acute Toxicity to Mysid Shrimp (Mysidopsis 

bahia): Report No. TMUE 0005/B. Prepared by Springborn Laboratories, 

Inc. 12 p. 

92027022 Registrant 

Summary

Royal, D. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00089045. 

Cypermethrin: Determination of the Acute Toxicity of Technical Material to 

the Fiddler Crab (Uca pugilator): Report No. TMUE 0003/B. Prepared by 

Springborn Laboratories, Inc. 15 p. 

89051 Stability test Ussary, J.P.; Fitzpatrick, R.D.; Foreman, L.A.; et al. (1981) Cy- permethrin 

Stability in Marine Laboratory Test Systems: Report Series TMU0558/B. 

(Unpublished study received Dec 30, 1981 under 10182-64; submitted by 

ICI Americas, Inc., Wilmington, Del.; CDL:070562-Q) 

46591503 Contract draft 

available

Putt, A. (2005) Cypermethrin - Toxicity to Estuarine Amphipods 

(Leptocheirus plumulosus) During a 28-Day Sediment Exposure. Project 

Number: 13656/6111. Unpublished study prepared by Springborn Smithers 

Laboratories. 85 p.

Accession 

No.

070562

2016143

2016156

Thompson, R.S. (1981) Investigation of the Acute Toxicity of PP383 to 

Larvae of the Pacific Oyster (Crassostrea gigas). Unpublished Report by the 

Brixham Laboratory of Imperial Chemical Industries, Ltd., Submitted 

12/28/81 by ICI Americas Inc., Wilmington, Delaware.

42444601 2016178

2016179

Ward, Timothy J., Robert L. Boeri and Mark A. Palmieri (1992) Acute 

Toxicity of FMC 56701 Technical and Cypermethrin Technical to the Mysid, 

Mysidopsis bahia. FMC Study Number A91-3454. Submitted by FMC 

Corporation. Performed by EnviroSystems Division, Resource Analysts, Inc. 

Hampton, New Hampshire. MRID No. 42444601.

72-4 Fish Early Life Stage/Aquatic Invertebrate Life Cycle Study

MRID Citation Reference

25770 2016141 Hill, R.W.; Maddock, B.G.; Hart, B. (1976) Determination of the Acute 

Toxicity of PP383 to Rainbow Trout (Salmo gairdnerii): Report No. 

BL/B/1711. (Unpublished study received Dec 31, 1979 under 10182-EX-19; 

prepared by Imperial Chemical Industries, Ltd., submitted by ICI Americas, 

Inc., Wilmington, Del.; CDL: 241598-H) 

25771 2016142 Hill, R.W.; Maddock, B.G.; Hart, B.; et al. (1977) Determination of the Acute 

Toxicity of PP 383 to Bluegill Sunfish (Lepomis macrochirus): Report No. 

BL/B/1775. (Unpublished study received Dec 31, 1979 under 10182-EX-19; 

prepared by Imperial Chemical Industries, Ltd., submitted by ICI Americas, 

Inc., Wilmington, Del.; CDL:241598-I) 

31224 DER not 

located

Bentley, R.E. (1976) Acute Toxicity of FMC-30980 to Bluegill (Lepomis 

macrochirus): NCT 634.61. (Unpublished study received Sep 28, 1976 

under 279-EX-63; prepared by EG&G, Bionomics, submitted by FMC Corp., 

Philadelphia, Pa.; CDL:227762-D) 
-Page 82 of 126-

89039 2016148 Jaber, M.J.; Hawk, R.E. (1981) The Toxicity of Cypermethrin to Fathead 

Minnow (Pimephales promelas) Embryos and Larvae: Report Series 

TMUE0007/B. (Unpublished study received Dec 30, 1981 under 10182-64; 

submitted by ICI Americas, Inc., Wilmington, Del.; CDL:070562-D) 

89047 2016163 Edwards, P.J.; Hamer, M.J.; Bull, J.M.; et al. (1981) Cypermethrin: 21 

Day~Daphnia magna~Life Cycle Study: Report Series RJ 0177B. 

(Unpublished study received Dec 30, 1981 under 10182-64; pre- pared by 

Imperial Chemical Industries, Ltd., submitted by ICI Americas, Inc., 

Wilmington, Del.; CDL:070562-M) 

42725301 2016180 Wheat, J. (1993) FMC-30980(carbon 14)-Cypermethrin: Chronic Toxicity to 

the Mysid, Mysidopsis bahia, Under Flow-Through Test Conditions: Lab 

Project Number: J9205004A. Unpublished study prepared by Toxikon

Environmental Sciences. 63 p. 

42898301 2016182 Wheat, J. (1993) FMC-30980 ((carbon 14) labeled Cypermethrin): Chronic 

Life-Cycle Toxicity to the Water Flea, Daphnia magna, Under Flow-through 

Test Conditions: Lab Project Number: J9205004B: A91-3479. Unpublished 

study prepared by Toxikon Environmental Sciences. 71 p. 

44546035 2016192 Sousa, J. (1998) (Carbon 14)(Beta)-Cypermethrin--Chronic Toxicity to 

Mysids (Mysidopsis bahia) Under Flow-Through Conditions: Final Report: 

Lab Project Number: 97-12-7170: 12442.1096.6232.530. Unpublished study 

prepared by Springborn Labs., Inc. 101 p. 

92027023 Registrant 

Summary

Royal, P. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00089039. 

Cypermethrin: Early Life Stages Test Fathead Minnow (Pimephales 

promelas): Report No. TMUE 0007/B. Prepared by Springborn Laboratories, 

Inc. 14 p. 

92027024 Registrant 

Summary

Royal, P. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00089044. 

Cypermethrin: Invertebrate Life-Cycle Test in Mysid Shrimp (Mysidopsis 

bahia): SLI TMUE 0005/B.: 16 p 

92027025 Registrant 

Summary

Hamer, M. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00089047. 

Cypermethrin: 21 Day Daphnia magna Life-cycle Study: Report No.: 

RJ0177B; PP383/CN/04. Prepared by ICI Agrochemicals Jealott's Hill 

Research Station 17 p. 

46591503 2086352 Marine Amphipod 28 Day Whole Sediment toxicity 

850.1300 Daphnid chronic toxicity test

MRID Citation Reference

47885103 Contract draft 

available

Cafarella, M. (2008) Cypermethrin: Full Life Cycle Toxicity Test with Water 

Fleas, Daphnia magna under Flow-Through Conditions: Reformatted Final 

Report. Project Number: 1084/012/231, A2007/6309. Unpublished study 

prepared by Springborn Smithers Laboratories (Europe). 87 p.

47944027 DER not 

located

Garforth, B. (1982) WL 85871 and Cypermethrin: Chronic Toxicity to 

Daphnia magna. Project Number: AL/523/001/OCR, AL/523/001, 

SBGR/82/119. Unpublished study prepared by Sittingbourne Research 

Center. 46 p.
-Page 83 of 126-

72-5 Life cycle fish

MRID Citation Reference

40102101 Status report Hill, R.; Tapp, J. (1987) Status Report at Day 30 Post-hatch Cypermethrin 

(PP383) Fathead Minnow Lifecycle Study: Lab. Pro- ject ID: (P171/C). 

Unpublished study prepared by Imperial Chem- ical Industries PLC, Brixham 

Laboratory. 7 p. 

40427901 Status report Hill, R.; Tapp, J. (1987) Status Report on Cypermethrin (PP383) Fathead 

Minnow Lifecycle Study (P171/C): Laboratory Project ID P171/C. 

Unpublished study prepared by Imperial Chemicals Industries PLC. 13 p. 

40529601 Status report Hill, R.; Tapp, J. (1988) Status Report of Cypermethrin (PP383) Fathead 

Minnow Lifecycle Study (P171/c). Laboratory Project ID P171/C. 

Unpublished study prepared by Imperial Chemicals Industries PLC, 

England. 4 p. 

40641701 DER not 

located

Tapp, J.; Hill, R.; Maddock, B.; et al. (1988) "Cypermethrin: Determination of 

Chronic Toxicity to Fathead Minnow (Pimephales promelas) Full Lifecycle": 

Laboratory Project ID BL/B/3173. Unpublished study prepared by ICI PLC, 

Brixham Laboratory. 189 p. 

41092101 addendum Tapp, J. (1988) Cypermethrin: Determination of Chronic Toxicity to Fathead 

Minnow (Pimephales Promelas) Full Lifecycle. Addendum to Brixham 

Laboratory Report No. BL/B/3173: Laboratory ID No. FT5/86/P171/C. 

Unpublished study prepared by ICI Brixham Labor- atory. 12 p. 

92027026 Registrant 

summary

Adams, D. (1990) ICI Americas Inc. Phase 3 Summary of MRID 40641701. 

Cypermethrin: Determination of the Chronic Toxicity to Fathead Minnow 

(Pimephales promelas): Report Nos. BL/B/3173/3507; Study No. P171/C.: 

19 p. 

40102100 Interim report Imperial Chemical Industries PLC (1987) Interim Report on Fish Lifecycle 

Study of Cypermethrin in Response to Data Call-in Notice. Compilation of 1 

study. 

72-6 Aquatic org. accumulation

MRID Citation Reference

42868203 Check Fate 

Data

Giroir, E.; Stuerman, L. (1993) Cypermethrin (carbon 14) Bioconcentration 

by Bluegill Sunfish (Lepomis macrochirus): Lab Project Number: 

191E5491E1: 40018: PC-0189. Unpublished study prepared by ABC Labs, 

Inc. 311 p. 

72-7 Simulated or Actual Field Testing

MRID Citation Reference

40125601 Suitability 

evaluation

Cole, J.; Brantly, T.; Hodges, J.; et al. (1987) Cypermethrin: Evaluation 

during 1986 of "Speir II" (Alabama, USA) Farm Pond Drainage Basin and 

Ecosystem for Suitability for a 1987 Cyper- methrin Study: I: Laboratory 
-Page 84 of 126-

Project ID: RJ0553B. Unpublished study prepared by Imperial Chemical 

Industries. 382 p. 

40125602 Suitability 

evaluation

Cole, J.; Brantly, T.; Hodges, J.; et al. (1987) Cypermethrin: Evaluation 

during 1986 of "Mayo" (Alabama, USA) Farm Pond Drain- age Basin and 

Ecosystem for Suitability for a 1987 Cypermethrin Study: I: Laboratory 

Project ID: RJ0557B. Unpublished study prepared by Imperial Chemical 

Industries. 376 p. 

40125603 Suitability 

evaluation

Hill, I.; Cole, J. (1987) Comparison of "Speir II" and "Mayo" Farm Ponds

(Alabama) USA: Laboratory Project ID: M4428B. Unpublished study 

prepared by Imperial Chemical Industries. 20 p. 

40804501 2016160 Rea, D.; Brantly, T.; Grimmett, J.; et al. (1988) Cypermethrin: Evaluation of 

the Impact of Aerially Sprayed Cypermethrin on the Aquatic Ecosystem of a 

Farm Pond in the Drainage Basin of a Cotton Crop: 1987: Laboratory 

Project ID RH0629B. Unpublished study prepared by ICI Agrochemicals. 

744 p. 

40804502 Suitability 

evaluation

Cole, J.; Brantly, T.; Hodges, J.; et al. (1988) Cypermethrin: Evaluation 

during 1986 of "Speir II" (Alabama, USA) Farm Pond Drainage Basin and 

Ecosystem for Suitability for a 1987 Cypermethrin Study: II: Laboratory 

Project ID RJ0591B. Unpub- lished study prepared by ICI Agrochemicals. 

508 p. 

41011501 addendum Sadler, J. (1989) Cypermethrin: Addendum to RJ0629B: Evaluation of the 

Impact of Aerially Sprayed Cypermethrin on the Aquatic Eco- system of a 

Farm Pond in the Drainage Basin of a Cotton Crop: 1987: Project ID: 

PP383-CF-04/2. Unpublished study prepared by Jeallot's Hill Research 

Station. 14 p. 

41218801 Progress 

report

Palmieri, M. (1989) Aquatic Mesocosm Study of Pesticide Products 

Containing the Active Ingredient Cypermethrin: Progress Rept. 1: Study No. 

A89-2847. Unpublished study prepared by Wildlife International, Ltd. 17 p. 

41336201 Progress 

report

Palmieri, M. (1989) Aquatic Mesocosm Study of Pesticide Products 

Containing the Active Ingredient Cypermethrin: Progress Report 3: FMC 

Study No. A89-2847. Unpublished study prepared by Wildlife International, 

Ltd. and FMC Corp. 5 p. 

41403101 Progress 

report

Palmieri, M. (1990) Aquatic Mesocosm Study of Pesticide Products 

Containing the Active Ingredient Cypermethrin: Progress Report 4: Lab 

Project Number: A89-2847. Unpublished study prepared by Wildlife 

International, Ltd. in association with FMC Corp. 55 p. 

41466301 Progress 

report

Palmieri, M. (1990) Aquatic Mecocosm Study of Pesticide Products 

Containing the Active Ingredient Cypermethrin: Progress Report. 

Unpublished study prepared by Wildlife International, Ltd. 7 p. 

41541101 Progress 

report

Palmieri, M. (1990) Aquatic Mesocosm Study of Pesticide Products 

Containing the Active Ingredient Cypermethrin: Progress Report 6: Lab 

Project No. A89-2847. Unpublished study prepared by Wildlife International, 

Ltd. 14 p. 

41616201 Progress 

report

Palmieri, M. (1990) Aquatic Mesocosm Study of Pesticide Products 

Containing the Active Ingredient Cypermethrin: Progress Report 7: Project 

Number: A89-2847. Unpublished study prepared by Wildlife International, 

Ltd., and FMC Corp. 14 p. 
-Page 85 of 126-

41670701 Progress 

report

Palmeri, M. (1990) Aquatic Mesocosm Study of Pesticide Products 

Containing the Active Ingredient Cypermethrin: Progress Report 8: Lab 

Project Number: A89-2847. Unpublished study prepared by Wildlife 

International, Ltd., and FMC Corp. 14 p. 

41732501 Progress 

report

Palmieri, M. (1990) Aquatic Mesocosm Study of Pesticide Product 

Containing the Active Ingredient Cypermethrin: Progress Report 9: Project 

Number: A89-2847. Unpublished study prepared by Wildlife International, 

Ltd and FMC Corp. 13 p. 

41800601 Progress 

report

Palmieri, M. (1991) Aquatic Mesocosm Study of Pesticide Products 

Containing the Active Ingredient Cypermethrin: Progress Report 10. Lab 

Project Number: A89-2847. Unpublished study prepared by Wildlife 

International, Ltd. and FMC Corp. 12 p.

41862501 Progress 

report

Palmieri, M. (1991) Aquatic Mesocosm Study of Pesticide Products 

Containing the Active Ingredient Cypermethrin: Progress Report 11: Lab 

Project Number: A89-2847. Unpublished study prepared by Wildlife 

International, Ltd. & FMC Corp. 58 p. 

42148201 DER not 

located

Palmieri, M.; Freda, J.; Krueger, H.; et al. (1991) An Evaluation of the 

Impact of Cypermethrin Exposure on Managed Aquatic Ecosystems: Lab 

Project Number: 104-160: A89-2847. Unpublished study prepared by 

Wildlife International Ltd. 1612 p.

40125604 Protocol Hill, I. (1987) Protocol--Cypermethrin: A Study of the Impact of Aerially 

Sprayed Cypermethrin on the Aquatic Ecosystem of a Farm Pond in the 

Drainage Basin of a Cotton Crop: Laboratory Project ID: 383/CF/04. 

Unpublished study prepared by Imperial Chemical Industries. 31 p. 

40967301 Addendum Sadler, J.; Hill, I. (1989) Cypermethrin: Addendum to RJ0629B ...; 

Evaluation of the Impact of Aerially Sprayed Cypermethrin on the Aquatic 

Ecosystem of a Farm Pond in the Drainage Basin of a Cotton Crop; 1987: 

Project ID; PP383-CT-04/1. Unpublished study prepared by ICI 

Agrochemicals. 11 p. 

41293901 Progress 

report

Palmieri, M. (1989) Aquatic Mesocosm Study of Pesticide Products 

Containing the Active Ingredient Cypermethrin: Progress Report 2: Lab 

Project Number: A89/2847. Unpublished study prepared by Wildlife 

International, Ltd. in Association with FMC Corp. 5 p. 

42081101 Progress 

report

Palmieri, M. (1991) Aquatic Mesocosm Study of Pesticide Products 

Containing the Active Ingredient Cypermethrin: Progress Report 14: Lab 

Project Number: A89-2847. Unpublished study prepared by Wildlife 

International, Ltd. and FMC Corp. 8 p. 

Acc No.

250506

128704

2016157 Jaber, M.; Hawk, R. (1983) Cypermethrin: Aquatic Ecological Effects under 

Field Use Conditions in Cotton: Selma, Alabama, 1980: Re- port Series 

TMUE0026/B. (Unpublished study received Mar 24, 1983 under 10182-65; 

submitted by ICI Americas, Inc., Wilming- ton, DE; CDL:250506-A)

152737 DER not 

located

Getty, C.; Wilkinson, W.; Swaine, H.; et al. (1983) Cypermethrin: Effects of 

Multiple Low Rate Applications on Experimental Ponds: Report No. 

RJ0182B. Unpublished study prepared by Imperial Chemical Industries 

PLC. 62 p. 

155770 Open lit Crossland, N. (1982) Aquatic toxicology of cypermethrin. II. Fate and 

biological effects in pond experiments. Aquatic Toxicology 2:205-222. 
-Page 86 of 126-

155772 Open lit Crossland, N.; Shires, S.; Bennett, D. (1982) Aquatic toxicolofy of 

cypermethrin. III. Fate, and biological effects of spray drift deposits in fresh 

water adjacent to agricultural land. Aquatic Toxicology 2:253-270. 

141-1 Honey bee acute contact

MRID Citation Reference

155740 2016158 Bull, J.; Wilkinson, W. (1980) Cypermethrin: Laboratory Determina- tion of 

the Acute Toxicity to Honeybees of Technical Material and an Emulsifiable 

Concentrate (GFU 061): Report Series: RJ 0169B. Unpublished study 

prepared by ICI Plant Protection Div. 35 p. 

44544208 2016183 Halsall, N. (1998) Betacypermethrin 10 EC: Acute Toxicity to Honey Bees 

(Apis mellifera): Lab Project Number: PWT 131/963589: PWT 131. 

Unpublished study prepared by Huntingdon Life Sciences Ltd. 29 p. 

92027047 Registrant 

Summary

Lewis, G. (1990) ICI Americas Inc. Phase 3 Summary of MRID 00155740. 

Cypermethrin: Acute Contact and Oral Toxicity to Honey Bees (Apis 

mellifera: Report No. RJ0169B; Study No.: PP383/CM/01. Prepared by ICI 

Agrochemicals Jealott's Hill Research Station. 14 p. 

92027048 Registrant 

Summary

Lewis, G. (1990) ICI Americas Inc. Phase 3 Summary of MRID 40274001. 

Cypermethrin: Toxicity of Residues on Foliage to Honey Bees (Apis 

mellifera): Report No. RJ0587B; Study No.: PP383CM03. Prepared by ICI 

Agrochemicals Jealott's Hill Research Station. 13 p. 

47800504 Open lit- DER 

not located

Decourtye, A.; Devillers, J.; Genecque, E.; et al. (2005) Comparative 

Sublethal Toxicity of Nine Pesticides on Olfactory Learning Performances of 

the Honeybee Apis mellifera. Archives of Environmental Contamination 

and Toxicology 48:242-250.

47800530 Open lit- DER 

not located

Chauzat, M.; Carpentier, P.; Martel, A.; et al. (2009) Influence of Pesticide 

Residues on Honey Bee (Hymenoptera: Apidae) Colony Health in France. 

Environ. Entomol. 38(3):514-523.

141-2 Honey bee residue on foliage

MRID Citation Reference

40274001 2016159 Gough, H.; Jackson, D.; Wilkinson, W. (1987) Cypermethrin: Toxicity of 

Residues on Foliage to Honey Bees (Apis mellifera): Laborato- ry Project ID: 

RJ0587B. Unpublished study prepared by ICI Plant Protection Division. 27 

p. 

41699401 Registrant 

summary

Lewis, G. (1990) Phase 3 Summary of MRID 40274001: Cypermethrin: 

Toxicity of Residues on Foliage to Honey Bees (Apis mellifera): Lab Project 

Number: RJ0587B: PP383CM03. Unpublished study pre- pared by ICI 

Agrochemicals, Jealotts Hill Research Station. 13 p. 

141-3 Toxicity to Non Target Insects

5009995 Open lit

2079040

Waddill, V.H. (1978) Contact toxicity of four synthetic pyrethroids and 

methomyl to some adult insect parasites. Florida Entomologist 61(1):27-30. 
-Page 87 of 126-

127368 Open lit Harris, C.; Turnbull, S. (1978) Laboratory studies on the contact toxicity and 

activity in soil of four pyrethroid insecticides. Canadian Entomologist 

110(Mar):285-288. (Submitter AW-81-0099; also In unpublished submission 

received Apr 8, 1983 under 39398- 16; submitted by Sumitomo Chemical 

America, Inc., New York, NY; CDL:249939-B) 

850.1790 Chironomid Sediment Toxicity Test

MRID Citation Reference

46871501 Summary of 

multiple 

studies

Giddings, J. (2006) Overview of Sediment Toxicity Studies with Synthetic 

Pyrethroids. Project Number: 06723, 06273. Unpublished study prepared by 

Compliance Services International. 62 p.

850.7100 Data reporting for environmental chemistry methods

MRID Citation Reference

47053001 DER not 

located

Robinson, N. (2007) Residue Analytical Method for the Determination of 

Residues of Bifenthrin, Cypermethrin, Cyfluthrin, Deltamethrin, 

Esfenvalerate, Fenpropathrin, Lambda-cyhalothrin and Permethrin in 

Sediment. Unpublished study prepared by Syngenta Jealotts Hill 

International. 185 p.

47053002 DER not 

located

Reed, R. (2006) Laboratory Validation: Validation of the Residue Analytical 

Method: Residue Analytical Method for the Determination of Residues of 

Bifenthrin, Cypermethrin, Cyfluthrin, Deltamethrin, Esfenvalerate, 

Fenpropathrin, Lambda - Cyhalothrin and Permethrin in Sediment: Final 

Report. Project Number: MLI/06/02, ML06/1286/PWG. Unpublished study 

prepared by Morse Laboratories Inc. 418 p.

850.1735 Whole sediment: acute freshwater invertebrates

MRID Citation Reference

47946601 Contract draft 

available

Picard, C. (2009) 10-Day Toxicity Test Exposing Freshwater Amphipods 

(Hyalella azteca) to Cypermethrin Applied to Glen Charlie Pond Sediment 

Under Static-Renewal Conditions. Project Number: 13656/6130, 

100808/OPPTS/10/DAY/HYALELLA/MA/SED. Unpublished study prepared 

by Springborn Smithers Laboratories. 117 p.

47946602 Contract draft 

available

Picard, C. (2009) 10-Day Toxicity Test Exposing Freshwater Amphipods 

(Hyalella azteca) to Cypermethrin Applied to Formulated Sediment Under 

Static-Renewal Conditions. Project Number: 13656/6129. Unpublished 

study prepared by Springborn Smithers Laboratories. 118 p.

47946603 Contract draft 

available

Picard, C. (2009) 10-Day Toxicity Test Exposing Freshwater Amphipods 

(Hyalella azteca) to Cypermethrin Applied to California Sediment 2 Under 

Static-Renewal Conditions. Project Number: 13656/6127. Unpublished 

study prepared by Springborn Smithers Laboratories. 119 p.

47946604 Contract draft 

available

Picard, C. (2009) 10-Day Toxicity Test Exposing Freshwater Amphipods 

(Hyalella azteca) to Cypermethrin Applied to CA Sediment 1 Under Static-
-Page 88 of 126-

Renewal Conditions. Project Number: 13656/6126. Unpublished study 

prepared by Springborn Smithers Laboratories. 118 p.

47946605 Contract draft 

available

Picard, C. (2009) 10-Day Toxicity Test Exposing Freshwater Amphipods 

(Hyalella azteca) to Cypermethrin Applied to California Sediment 3 Under 

Static-Renewal Conditions. Project Number: 13656/6128, 

100808/OPPTS/10/DAY/HYALELLA/CAS3. Unpublished study prepared by 

Springborn Smithers Laboratories. 116 p.

46591504 2086351 Putt, A. (2005) Cypermethrin - Toxicity to Midge (Chironomus tentans) 

During a 10-Day Sediment Exposure. Project Number: 13656/6110. 

Unpublished study prepared by Springborn Smithers Laboratories. 88 p.

46725701 2086353 Putt, A. (2005) Cypermethrin - Life-Cycle Toxicity Test with Midge 

(Chironomus tentans) During a 60-Day Sediment Exposure. Project 

Number: 13656/6112. Unpublished study prepared by Springborn Smithers 

Laboratories. 117 p.

Non Guideline Selections

90000 2016265 

summary pg 

29

Brown, S.M.; Edwards, P.J. (1980) Cypermethrin (PP383): Effects on 

Earthworms,~Lumbricidae?~: Report Series RJ 0151B. (Unpublished 

study received Dec 30, 1981 under 10182-64; prepared by Imperial 

Chemical Industries, Ltd., England, submitted by ICI Americas, Inc., 

Wilmington, Del.; CDL:070559-O) 

90001 2016265 

summary pg 

29

Cole, J.F.H.; Wilkinson, W. (1980) Cypermethrin (PP383): Effects on 

Soil Microarthropods: Report Series RJ 0150B; 5B 4/6. (Unpub- lished

study received Dec 30, 1981 under 10102-64; prepared by Imperial 

Chemical Industries, Ltd., England, submitted by ICI Americas, Inc., 

Wilmington, Del.; CDL:070559-P) 

90059 2016265 

summary pg 

56

2016265 

summary pg 

57

Curl, E.A.; Milner, S.D. (1980) Cypermethrin: Accumulation and Depletion of Radioactive Residues in the Tissues of Mallard Duck and 

Bobwhite Quail following Daily Dosing: Report Series RJ 0147B. 

(Unpublished study received Dec 30, 1981 under 10182-64; prepared 

by Imperial Chemical Industries Ltd., England, submit- ted by ICI 

Americas, Inc., Wilmington, Del.; CDL:070560-K) 

Leahey 1977. Similar study with Permethrin and Mallard and Japanese 

Quail

138935 DER not 

located

Hill, I. (1984) A Review of the Effects of Pyrethrum and Synthetic 

Pyrethroids on Non-target Organisms in Terrestrial and Aquatic 

Environments: Report Series RJ0349B. (Unpublished study re- ceived 

Jan 30, 1984 under 10182-65; prepared by Imperial Chemi- cal 

Industries, Ltd., Eng., submitted by ICI Americas, Inc., Wilmington, DE; 

CDL:252348-A) 

149692 DER not 

located

Rajakulendran, S.; Plapp, F. (1982) [Comparative Toxicities of Five 

Synthetic Pyrethroids to Various Parasites and Predators]. Unpublished compilation. 8 p. 

149693 DER not 

located

Zoecon Corp. (1983) Effects on Pollinators:[Fluvalinate]. Unpub- lished 

compilation. 15 p. 

155785 Open lit Stephenson, R.; Choi, S.; Olmos-Jerez, A. (1984) Determining the 
-Page 89 of 126-

toxicity and hazard to fish of a rice insecticide. Crop Protec- tion 

3(2):151-165.

155797 Check SETAC 

publications

Hill, I.; Hamer, M. (1984) The Influence of Adsorption and Degradation 

on the Toxicity of Permethrin, Cyperthrin and Cyhalothrin to Aquatic 

Organisms. Unpublished documents presented at the SETAC Fifth 

Annual Meeting, November, 1984; Washington, D.C. 2 p.

40135801 DER not 

located

Kaminski, B. (1987) Cypermethrin: Effect on Earthworms and Bioaccumulation Potential of Residues. Unpublished study prepared by ICI 

Americas. 7 p. 

40135802 DER not 

located

Arnold, J.; Edwards, P. (1983) Cypermethrin: Effects on Earthworms 

Lumbricidae of Repeated Annual Field Applications: Lab Project ID: 

RJ0311B. Unpublished study prepared by ICI Plant Protec- tion 

Division. 36 p. 

40135803 DER not 

located

Curl, E.; Leahey, J. (1984) Permethrin and Cypermethrin: Characterisation of Radioactive Residues Found in Earthworms Which Have 

Been Exposed to Soil Treated with [Carbon 14]-Permethrin and [Carbon 

14]-Cypermethrin: Lab Project ID: RJ0343B. Unpublished study 

prepared by ICI Plant Protection Division. 36 p. 

40135804 DER not 

located

Edwards, P.; Arnold, J. (1984) Cypermethrin and Permethrin: Accumulation of [Carbon 14]-Cypermethrin and [Carbon 14]-Permethrin 

Equivalents by the Earthworms Allolobophora calliginosa and Lumbricus terrestris: Lab Project ID: RJ0341B. Unpublished study prepared 

by ICI Plant Protection Division. 30 p. 

40135805 DER not 

located

Collis, W.; Leahey, J. (1984) Cypermethrin: Evaluation of Bioaccumulation Potential in Quail Dosed with Earthworms Containing 

Cypermethrin Derived Residues: Lab Project ID: RJ0330B. Unpublished study prepared by ICI Plant Protection Division. 35 p. 

40135806 DER not 

located

Cavell, R.; Leahey, J.; Lloyd, S. (1984) Cypermethrin: Evaluation of 

Bioaccumulation Potential in Rats Dosed with Earthworms Con- taining 

Cypermethrin Derived Residues: Lab. Project ID: RJ0352B. 

Unpublished study prepared by ICI Plant Protection Division. 35 p. 

40135807 DER not 

located

Leahey, J.; Curl, E.; Edington, C.; et al. (1985) Permethrin and 

Cypermethrin: Identification of a Major Component of the Radio- active 

Residue in Earthworms Exposed to Soil Treated with [Carbon-14]-

Benzyl-labeled Cypermethrin (Addendum to RJ0343B): Lab Project No.: 

RJ0391B. Unpublished study prepared by ICI Plant Protection Division. 

21 p. 

40359505 Open lit 

DER not 

located 

Watters, F.; White, N.; Cote, D. (1983) Effect of temperature on toxicity 

and persistence of three pyrethroid insecticides applied to fir plywood 

for the control of the red flour beetle (coleoptera: Tenebrionidae. 

Journal of Economic Entomology 76: 11-16.

44388401 Registrant 

Assessment

Maund, S.; Travis, K.; Hendley, P.; et al. (1997) Evaluation of the 

Ecological Risks of Cotton Pyrethroids to Aquatic Ecosystems: Lab 

Project Number: RC0009B. Unpublished study prepared by Zeneca 

Agrochemical (Zeneca Ltd.). 30 p. 

44396501 Registrant 

Assessment

Solomon, K. (1997) Review of the Laboratory Aquatic Organism Toxicity 

Data for the Cotton Pyrethroids: Distributional Analysis of the Acute 
-Page 90 of 126-

Toxicity Data. Unpublished study prepared by University of Guelph. 76 

p. 

44396502 Registrant 

Assessment

Travis, K. (1997) A Modified Tier II Aquatic Exposure Analysis of Cotton 

Pyrethroids, Incorporating Landscape-Level Exposure Factors: Lab 

Project Number: PYRETHROIDS\3. Unpublished study prepared by 

Zeneca Agrochemical (Zeneca Ltd). 221 p. 

44396503 Registrant 

Assessment

Giddings, J. (1997) Aquatic Mesocosm and Field Studies with Cotton 

Pyrethroids: Observed Effects and Their Ecological Significance: Lab 

Project Number: 97-6-7014: 13656.0497.6100.900. Unpublished study 

prepared by Springborn Labs., Inc. 102 p. 

44396504 Registrant 

Assessment

Ritter, A.; Williams, W.; Cheplick, J. (1997) Tier 1 and Tier 2: Modeling 

of Pyrethroid Exposure to Aquatic Nontarget Organisms Associated with 

Use on Cotton: Lab Project Number: WEI 794.01: PWG. Unpublished 

study prepared by Waterborne Environmental, Inc. (WEI). 80 p. 

45245501 Registrant 

Assessment

Soderlund, D.; Clark, J.; Mullin, L. et al. (2000) Pyrethroid Insecticides: 

Is there a Common Mechanism of Mammalian Toxicity?: Lab Project 

Number: PWG FQPA 2000-01. Unpublished study prepared by 

Pyrethroid Working Group. 144 p. 

45867701 DER not 

located - not a 

cypermethrin 

study

Smith, E.; Du Preez, L.; Solomon, K. (2003) Field Exposure of Xenopus 

laevis to Atrazine and Other Triazines in South Africa: Exposure 

Characterization and Assessment of Laryngeal and Gonadal 

Responses: Final Report: Lab Project Number: SA-01B: 109-02: C1. 

Unpublished study prepared by The Institute of Environmental and 

Human Health, Texas Tech University and School of Environmental 

Sciences and Development Potchefstroom, University for CHE. 91 p. 

45867709 DER not 

located – not 

a 

cypermethrin 

study

Smith, E.; Du Preez, L.; Solomon, K. (2003) Field Exposure of Xenopus 

laevis to Atrazine and Other Triazines in South Africa: Feasibility Study 

for Site Characterization and Assessment of Laryngeal and Gonadal 

Responses: Final Report: Lab Project Number: SA-01A: 2011-02: C1. 

Unpublished study prepared by The Institute of Environmental and 

Human Health Texas Tech University and School of Environmental 

Sciences and Development Potchefstroom University for CHE. 104 p. 

46051301 Registrant 

Assessment

Ritter, A.; Williams, W. (2003) Tier 2 Modeling of Pyrethroid Compounds 

Exposure to Aquatic Nontarget Organisms Associated with Use on 

Cotton: Final Report. Project Number: WEI/794/03. Unpublished study 

prepared by Waterborne Environmental, Inc. (WEI). 180 p.

47050501 Registrant 

Assessment

Breckenridge, C.; Holden, L. (2007) Evidence for Separate Mechanism 

of Action for Type I and Type II Pyrethroid Insecticides. Project Number: 

PWG/TOX/2007/01. Unpublished study prepared by Pyrethroid 

Working Group. 144 p.

47050502 Open lit Burr, S.; Ray, D. (2004) Structure-Activity and Interaction Effects of 14 

different Pyrethroids on Voltage-Gated Chloride Ion Channels. 

Toxicological Sciences 77(2):341-346.

47506602 DER not 

located

Hall, L.; Killen, W.; Anderson, R. (2008) A Comparison of Sediment 

Sampling Methods for Pyrethroids in Urban/Residential Sediments of 

California Streams and Additional Pyrethroid Sampling in Pleasant 

Grove Creek Backwater Surrogate Sites- Pyrethroid: Assessment. 
-Page 91 of 126-

Project Number: T001584/08. Unpublished study prepared by Wye 

Research and Education Center. 62 p.

47506603 DER not 

located

Hall, L.; Killen, W.; Anderson, R.; et. al. (2008) An Assessment of 

Benthic Communities with Concurrent Physical Habitat, Pyrethroid, and 

Metals Analysis in an Urban and Residential Stream in California in 

2006 and 2007-Pyrethroid: Assessment. Project Number: T001523/08. 

Unpublished study prepared by Wye Research and Education Center 

and Northern Illinois University. 229 p.

47543609 Published deNoyelles, F.; Dewey, S.; Huggins, D.; et al. (1994) Aquatic 

Mesocosms in Ecological Effects Testing: Detecting Direct and Indirect 

Effects of Pesticides. P. 577-603 in Ecological Risk Assessment, 

CRC Press.

47929401 Progress 

report

Giddings, J. (2009) Pyrethroid Working Group Sediment Toxicity 

Testing Program: Progress Report #1: (Hyalella azteca). Project 

Number: 09713. Unpublished study prepared by Compliance Services 

International. 26 p.

47929402 Overview Giddings, J. (2009) Pyrethroid Working Group Sediment Toxicity 

Testing Program: Overview of Part 1 (Comparison of Sediments with 

Different Organic Content): (Hyalella azteca). Project Number: 09718. 

Unpublished study prepared by Compliance Services International. 25 

p.

47929403 Progress 

report

Giddings, J. (2009) Pyrethroid Working Group Sediment Toxicity 

Testing Program: Progress Report #2: (Hyalella azteca). Project 

Number: 09744. Unpublished study prepared by Compliance Services

International. 11 p.

47929404 Registrant 

Assessment

Hall, L.; Killen, W.; Anderson, R.; et al. (2009) An Assessment of the 

Potential Influence of Physical Habitat, Pyrethroids and Metals of 

Benthic Communities in a Residential Stream in California in 2008: 

(Tubificidae, Paratanytarsus sp., Hyalella sp., Physa sp., Dugesia tigrina 

and Dero digatata): Final Report. Project Number: T001605/09. 

Unpublished study prepared by Compliance Services International. 126 

p.

47929405 DER not 

located

Hall, L.; Killen, W.; Alden, R. (2007) An Assessment of Benthic 

Communities with Concurrent Physical Habitat, Pyrethroid, Metals and 

PAH Analysis in an Urban and Residential Stream in California: (Seed 

Shrimp, Snails, Chironomids, Oligochaetes and Black Flies). 

Unpublished study prepared by Wye Research and Education Center, 

and Northern Illinois University. 173 p.

47929406 DER not 

located

Hall, L.; Killen, W.; Anderson, R. (2009) A Comparison of Targeted 

Sedimemt Sampling Methods for Pyrethroids in Urban/Residential 

Sediments of a California Stream in 2008: (Hyalella azteca): Final 

Report. Project Number: T001763/09. Unpublished study prepared by 

Wye Research and Education Center. 56 p.

47944033 Comparison 

summary

Wisk, J. (2010) Comparison of Ecotoxicology Endpoints for AlphaCypermethrin and Cypermethrin. Project Number: 2010/7002965/OCR, 

2010/7002965. Unpublished study prepared by BASF Agricultural 

Products Center. 9 p.
-Page 92 of 126-

41068006 Open litdifferent 

chemical

Bradbury, S.; Coats, J.; McKim, J. (1985) Differential toxicity and uptake 

of two fenvalerate formulations in fathead minnows (Pimepholes 

promelas). Environmental Toxicology and Chemistry 4:531- 541.

129064 Zeta-Cypermethrin Ecoeffects Bibliography 

72-2 Acute Toxicity to Freshwater Invertebrates

MRID Citation Reference

41968210 2046958

Contract draft

Ward, T.; Boeri, R. et al. (1991) Acute Toxicity of FMC 56701 Technical and Cypermethrin Technical to the Daphnid, Daphnia magna: Lab 

Project Number: 90186-FMC: A90-3310. Unpublished study prepared 

by Resource Analysts, Inc. 46 p. 

43293501 2046962

Contract draft

Wheat, J.; Evans, J. (1994) Zetacypermethrin Technical and 

Cypermethrin Technical: Comparative Acute Toxicity to the Water 

Flea (Daphnia magna), under Flow-Through Test Conditions: Lab 

Project Number: J9210001B: A92/3636. Unpublished study prepared by 

Toxikon Environmental Sciences. 76 p. 

72-1 Acute Toxicity to Freshwater Fish

41868208 or 

41968208?

2046956

Contract draft

Overman, M.A., M.G. Barron and D.D. Vaishnav (1990) Cypermethrin-S 

(FMC 56701): Acute Toxicity to Rainbow Trout (Oncorhynchus mykiss) 

Under Flow-Through Test Conditions. Laboratory Project ID 3903026-

0700-3140. FMC Study No. A89-2935-01. Prepared by Environmental 

Science and Engineering, Inc., Gainesville, FL. Submitted by FMC 

Corporation, Philadelphia, PA. EPA MRID No. 41968208.

7-3 Acute Toxicity to Estuarine/Marine Organisms

MRID Citation Reference

41968211 2046959

Contract draft

Overman, M.; Barron, M.; Vaishnav, D. (1990) Cypermethrin-S (FMC 

56701): Acute Toxicity to Sheepshead Minnow (Cyprinodon variegatus) under Flow-through Test Conditions: Lab Project Number: 

3903026-0600-3140: A89-2937-01. Unpublished study prepared by 

Environmental Science and Engineering, Inc. 47 p. 

41968213 2046961

Contract draft

Ward, T.; Boeri, R. (1991) Acute Toxicity of FMC 56701 Technical and 

Cypermethrin Technical to the Mysid, Mysidopsis bahia: Lab Project 

Number: 90187-FMC: A90-3309. Unpublished study prepared by 

Resource Analysts, Inc. 52 p. 

42411001

or 41968212

2046960 

contract 

draft- signed 

copy missing

Yurk, J.; Chandler, A. (1992) FMC 45806: Acute Toxicity to Sheepshead 

Minnow (Cyprinodon variegatus) under Flow-through Test Conditions: 

Amended Final Report: Lab Project Number: A89-3111: 3903026-

0350-3140: C-BIO90.1/FMC458CV.2. Unpublished study prepared by 

Hunter/ESE, Inc. 43 p. 

42444601 2016179 in 

109702 

Cypermethrin

Ward, T.; Boeri, R.; Palmieri, M. (1992) Acute Toxicity of FMC 56701 

Technical and Cypermethrin Technical to the Mysid, Mysidopsis 

bahia: Final Report: Lab Project Number: 91186-FMC: A91-3454. 
-Page 93 of 126-

Unpublished study prepared by Resource Analysts, Inc. 50 p. 

41968212 2046960 Chandler, A.B. (1990) FMC 45806: Acute Toxicity to Sheepshead 

Minnow (Cyprinodon variegates) Under Flow-Through Test Conditions. 

Laboratory Project No. 3903026-0350-3140. Study Performed by 

Environmental Science and Engineering, Inc., Gainesville, FL. 

Submitted by FMC Corporation, Philadelphia, PA. EPA MRID No. 

42968212.
-Page 94 of 126-

Appendix A. Alpha-Cypermethrin Bridging Strategy

EFED’s Interim Policy for Stereoisomeric Pesticides (2000) outlines the minimal dataset required to 

determine whether enriched enantiomeric mixtures are of greater environmental concern than the already 

registered racemic mixture. This data is necessary because enantiomers may exhibit selective geological 

effects (stereoselectivity) towards inherently chiral-rich organisms. As part of the bridging strategy for 

alpha-cypermethrin, the registrant, BASF, submitted the required minimal dataset for the Agency to

assess the relative behavior of the enriched enantiomeric mixture, alpha-cypermethrin, versus the racemic 

mixture, cypermethrin (PC Code 109702). 

In a memorandum, dated May 10, 2011, the Agency denied the bridging strategy for alpha-cypermethrin 

to racemic and zeta-cypermethin (USEPA, 2011; DP358283), citing lack of sufficient information to 

evaluate the environmental fate and toxicity data. Additional meetings and submissions were completed 

concluding with the current appendix outlining the Agency’s approach to briding the data from the 

racemic and zeta-cypermethrin to alpha-cypermethrin.

The agency has previously allowed the environmental fate and ecotoxicity database for cypermethrin to 

bridge with the enriched enantiomeric mixture, zeta-cypermethrin (PC Code 129064). Based on the 

similarities in the chemical properties and toxicological endpoints discussed below, environmental fate 

and ecotoxicity data are bridged between racemic cypermethrin and the enriched isomeric mixtures (i.e., 

alpha-cypmerthin and zeta-cypermethrin). For the purposes of risk assessment, chemical-specific alphacypermethrin data will be used where available. Where there are no chemical specific data for alphacypermethrin, data will be bridged from the database available for the cypermethrins (racemic and zetacypermethrin). 

Comparison of Racemic Cypermethrin with the Zeta- and Alpha-Cypermethrin 

Racemic cypermethrin consists of eight stereoisomers with two optically active centers (designated “R” 

and “S”). The isomers fall into four groups of two each. As seen in Table 1 below, zeta-cypermethrin 

also consists of the same eight stereoisomers, but in different proportions. Zeta is enriched in isomers 

with the second “S” configuration. However, both racemic and zeta cypermethrin contain 50% cis and 

50% trans isomers. Alpha-cypermethrin consists of only two of the eight stereoisomers, both of which are 

“cis.” These two isomers make up 22% of racemic and 25% of zeta-cypermethrin.

The result of this comparison is that racemic and zeta cypermethrin are more similar to each other, than 

either of them is to alpha-cypermethrin. In racemic, each of the 4 isomer groups is 22-28% of the total, 

and in zeta, each group is 25% of the total. Alpha contains 100% of cis-2 isomers, and none of the other 

three isomers groups. Therefore, if there are differences in the environmental fate of the eight isomers, 

this will be reflected as greater differences between racemic and zeta on one hand, and alpha on the other 

hand. 

Table A.1: Comparison (%) of stereoisomer composition of 

racemic, zeta- and alpha-cypermethrin

Isomer group Isomer Racemic 

cypermerthrin

Zeta 

cypermethrin

Alpha 

cypermethrin

Cis-1 1R, cis-R 14 3 0

1S, cis-S 14 22 0

Group subtotal 28 25 0

Cis-2 1R, cis-S 11 22 50
-Page 95 of 126-

1S, cis-R 11 3 50

Group subtotal 22 25 100

Trans-3 1R, trans-S 11 22 0

1S, trans-R 11 3 0

Group subtotal 22 25 0

Trans-4 1R, trans-R 14 3 0

1S, trans-S 14 22 0

Group subtotal 28 25 0

cis isomers (%) 50 50 100

Rationale for Bridging Fate Data

EFED received acceptable or supplemental data for the following studies using alpha-cypermethrin: 

• Aqueous photolysis, 

• Hydrolysis, 

• Adsorption/desorption, 

• Aerobic aquatic metabolism, and 

• Aerobic soil metabolism. 

Table A.2 provides a comparison of environmental fate data available for cypermethrin and alphacypermethrin. The hydrolysis (67 days for vs. 188, for alpha- and racemic, respectively), aqueous 

photolysis (5 days vs. 36), and aerobic soil metabolism (21 days vs. 60) data for alpha-cypermethrin 

indicate that it is somewhat less persistent than the racemic or enriched isomeric mixture zetacypermethrin. However, the aerobic aquatic metabolism and aerobic soil metabolism studies for alphacypermethrin were conducted on one sediment or soil, respectively, so differences between the enriched 

isomeric and racemic mixtures may not be fully understood. 

The 2000 EFED Interim Policy for Stereoisomeric Pesticides states, an aerobic soil metabolism study 

(GLN 162-1/835.3300) is required as part of the minimal data set for enantiomeric enriched 

mixtures. If the biotransformation rates and degradation products are substantially similar for the 

racemic and the enantiomeric enriched mixture, then no additional environmental fate data are 

needed. If on the other hand, the biotransformation rates and degradation products for the 

racemic and enantiomeric enriched mixture differ in a manner that suggests greater potential risk, 

then additional environmental fate data may be required on a case-by-case basis. EFED has not 

received alpha-cypermethrin specific data for soil photolysis and anaerobic soil metabolism; however, the 

registrant provided citations for racemic cypermethrin and zeta-cypermethrin data that was used in the 

Reregistration Eligibility Decision for Cypermethrin (RED, USEPA 2005). Where there are no chemical 

specific data for alpha-, data are bridged from the database available for the cypermethrins (racemic and 

zeta-cypermethrin). 

Table A.2. Available fate data for the cypermethrins.

Input Parameter

Racemic 

Cypermethrin 

Endpoint

AlphaCypermethrin 

Endpoint

Data Source(s)

Soil Photolysis Halflife 55 days NA Cyper –MRID 42129001

Aqueous Photolysis 

Half-life 36.2 days 5 days Cyper- MRID 42395701Alpha- MRID 48425003
-Page 96 of 126-

Aerobic Soil 

Metabolism Half-life 60 days 28 days

Cyper –MRID 42156601

Alpha – MRID 48425006

Anaerobic soil 

Metabolism Half-life

53.3 days (sandy loam, 

acid label)

63 days (sandy loam, 

alcohol label)

NA Cyper- MRID 42156602

Aerobic Aquatic 

Metabolism Half-life

(20°C)

8.9 days

10.1 days 2.8, 11 days Cyper- MRID 45920801

Alpha- MRID 48425011 and 48425012

Anaerobic Aquatic 

Metabolism Half-life

13.8 days (clay loam, 

benzyl label)

16.5 days (clay loam, 

cyclopropyl label)

NA Cyper- MRID 44876105

Adsorption/Desorption 

(Koc)

328,500 (Sand)

134,900 (Sandy loam)

82,600 (Silty loam)

20,800 (Clay loam)

26,492 – 144,662 Cyper- MRID 42129003

Alpha – MRID 48425008

Hydrolysis Half-life

(pH 7, 25°C) 188 days 67 days Cyper –MRID 42620501Alpha- MRID 48425002

Rationale for Bridging Ecological data

EFED received acceptable or supplemental data for the following studies using alpha-cypermethrin:

• Avian oral toxicity,

• Avian oral toxicity with a passerine species,

• Avian dietary toxicity,

• Avian reproduction,

• Honeybee acute contact toxicity,

• Acute freshwater fish toxicity,

• Acute freshwater invertebrate toxicity,

• Aquatic vascular plant toxicity,

• Aquatic nonvascular plant toxicity, and 

• Tier II vegetative vigor. 

Tables A.3 through A.5 provide a comparison of ecotoxicity data available for racemic cypermethrin, 

zeta-cypermethrin and alpha-cypermethrin. Based on the available information, alpha-cypermethrin has 

equal or lesser toxicity than either the racemic or zeta mixture. Where there are no chemical specific data 

for alpha-, data are bridged from the database available for the cypermethrins (racemic and zetacypermethrin).

TABLE A.3. Available ecological effects data for terrestrial animals exposed to cypermethrins.

Guideline Description

Racemic 

Cypermethrin 

Endpoint

AlphaCypermethrin 

Endpoint

ZetaCypermethrin 

Endpoint

Data Gap? Comments

850.2100 Avian oral 

toxicity

Bobwhite quail

LD50 > 2,000 mg 

a.i./kg-bw

(MRID 44546024

Acceptable)

Bobwhite quail

LD50 > 2025 mg 

a.i./kg-bw

NOAEL = 2025 

mg a.i./kg-bw

NA No

The alphacypermethrin data 

will be used. 
-Page 97 of 126-

(MRID 47944015

Acceptable)

850.2100

Avian oral 

toxicityPasserineNA

Zebra finch

LD50 = 1370 mg 

a.i./kg-bw

NOAEL < 504 mg 

a.i./kg-bw

(MRID 47944016)

Supplemental 

Qualitative)

NA Yes

The passerine data 

available is based 

on a supplemental 

study and may not 

be acceptable for 

calculating RQs.

850.2200 Avian dietary 

toxicity

Mallard duck

LC50 > 2,634 mg 

a.i./kg-diet

(MRID 00090071

Acceptable)

Bobwhite quail

LC50 > 4690 mg 

a.i./kg-diet

NOAEC = 631 mg 

a.i./kg-diet

LOAEC = 1250 

mg a.i./kg-diet

(MRID 47944017

Acceptable)

NA No

The alphacypermethrin data 

will be used.

850.2300 Avian 

reproduction

Mallard duck and 

bobwhite quail

NOAEC > 50 mg 

a.i./kg-diet

(MRID 00090072 

and 00090074)

Supplemental

Bobwhite quail

NOAEC < 48 mg 

a.i./kg-diet

LOAEC = 48 mg 

a.i./kg-diet

(MRID 47944018

Supplemental 

Qualitative)

Mallard duck and 

bobwhite quail

NOAEC = 50 

ppm

LOAEC > 50 

ppm

(MRID 00090073 

and 00090074

Acceptable)

No

The alphacypermethrin study 

is not suitable for 

use in calculating 

RQs. Therefore, 

the zetacypermethrin 

endpoint will be 

used because it is a 

definitive endpoint.

850.3020

Honeybee 

acute contact 

toxicity

NA

24-hr LD50 = 

0.033 μg a.i./bee

(MRID 47944019

Supplemental 

Qualitative)

48-hr LD50 = 

0.023 μg a.i./bee

(Acc No. 260647

Acceptable)

No

The alphacypermethrin data 

will be used.

TABLE A.4. Available ecological effects data for aquatic animals exposed to cypermethrins.

Guideline Description

Racemic 

Cypermethrin 

Endpoint

AlphaCypermethrin 

Endpoint

ZetaCypermethrin 

Endpoint

Data Gap? Comments

850.1075

Freshwater 

fish – Acute 

toxicity

Rainbow Trout

LC50 = 0.39 μg 

a.i./L

(MRID 

44546027

Acceptable)

Rainbow trout

LC50 = 2.2 μg 

a.i/L

NOAEC = 0. 

96 μg a.i./L

(MRID 

47944207

Acceptable)

NA No The alpha-cypermethrin 

data will be used.

850.1075

Saltwater 

fish – Acute 

toxicity

Sheepshead 

minnow

LC50 = 0.95 μg 

a.i./L

(MRID 

NA NA No The racemic cypermethrin 

endpoint will be used. 
-Page 98 of 126-

00090075

Acceptable)

850.1010

Freshwater 

invertebrates 

– Acute 

toxicity

Daphnid

48-hr EC50 = 

0.42 μg a.i./L

(MRID 

44546031

Acceptable)

Daphnid

EC50 = 0.067

μg a.i./L 

NOAEC = 

0.028 μg a.i./L

(MRID 

47944208

Acceptable)

Amphipod

96-hr LC50 = 

0.0036 μg 

a.i./L

(MRID 

44423501

Acceptable)

No

Though alpha-cypermethrin 

specific data is available, 

amphipods are known to be 

acutely more sensitive to 

pyrethroids than daphnids. 

Therefore, the zetacypermethrin endpoint will 

be used. 

850.1025

850.1035

Saltwater 

invertebrates 

–Acute 

toxicity

Mysid shrimp

96-hr LC50 = 

0.00475 μg 

a.i./L

(MRID 

42444601

Acceptable)

NA NA No The racemic cypermethrin 

endpoint will be used. 

850.1300

Freshwater 

invertebrate 

– life cycle 

test

NA NA NA Yes

For the purposes of this risk 

assessment a NOAEC value 

based on acute:chronic ratio 

will be used (0.00059 μg 

a.i./L).

850.1350

Saltwater 

invertebrates 

– life cycle 

test

Mysid shrimp

NOAEC = 

0.000781 μg 

a.i./L

LOAEC = 

0.00197 μg 

a.i./L

(MRID 

42725301

Acceptable)

NA NA No The racemic cypermethrin 

endpoint will be used. 

850.1400

Freshwater 

fish – early 

life stage 

test

Fathead 

minnow

NOAEC = 0.14 

μg a.i./L

LOAEC = 0.33 

μg a.i./L

(MRID 

00089039

Acceptable)

NA NA No The racemic cypermethrin 

endpoint will be used. 

850.1400

Saltwater 

fish – early 

life stage 

test

NA NA NA Yes

For the purposes of this risk 

assessment a NOAEC value 

based on acute:chronic ratio 

will be used (NOAEC = 

0.06 μg a.i./L). 

850.1735

Whole 

sedimentacute 

freshwater 

invertebrates

Amphipod

Experimental 

sediment value 

NOAE< 1.8 μg 

a.i./kg sediment

Derived pore 

water value 

NA NA No *Derived value
-Page 99 of 126-

NOAEC < 

0.00182 μg 

a.i./L pore 

water*

(MRID 

44074406

Acceptable)

850.1740

Whole 

sedimentacute marine 

invertebrates

NA NA NA Yes

Unpublished 

guideline

Whole 

sediment: 

chronic 

freshwater 

and marine 

invertebrates

NA NA NA No

The chronic NOAEC value 

for the mysid shrimp will 

be used as a surrogate for 

the chronic benthic 

invertebrate NOAEC for 

pore water (NOAEC = 

0.000781 μg a.i./L pore 

water) because of 

similarities in life stages 

exposed during chronic 

toxicity tests for both 

species. In addition the 

LC50 value for the mysid 

shrimp and Hyalella azteca

in 96-hour acute studies are 

very similar (LC50= 

0.00475 μg a.i./L for mysid 

and LC50 = 0.0036 μg 

a.i./L, indicating that these 

species experience similar 

toxicity to cypermethrin. 

TABLE A.5. Available ecological effects data for plants exposed to cypermethrins.

Guideline Description

Racemic

Cypermethrin

Endpoint

AlphaCypermethrin 

Endpoint

ZetaCypermethrin 

Endpoint

Data 

Gap? comments

850.4100

Terrestrial 

Plant 

toxicity: 

Tier I 

seedling 

emergence

NA NA NA No

850.4225

Terrestrial 

Plant 

toxicity: 

Tier II 

seedling 

emergence

NA NA NA No
-Page 100 of 126-

850.4150

Terrestrial 

Plant 

toxicity: 

Tier I 

vegetative 

vigor

NA NA NA No

850.4250

Terrestrial 

Plant 

toxicity: 

Tier II 

vegetative 

vigor

NA

Monocot: EC50 > 

0.0266 lbs a.i./A 

NOEC < 0.00333 

lbs a.i./A Dicot: 

EC50 > 0.0266 

lbs a.i/A NOEC = 

0.0133 lbs a.i./A

(MRID) 

47944210

Supplemental 

Qualitative)

NA No

Available study is 

supplemental for use in 

characterization only.

850.5400

Aquatic 

Plant 

Growth: 

algae

NA

Skeletonema 

costatum EC50 > 

33.5 μg a.i./L 

NOAEC = 33.5 

μg a.i/L

(MRID 47944032

Acceptable)

NA No

*EFED typically requires 

aquatic plant toxicity studies 

for at least 4 types of algae.

850.4400

Aquatic 

Plant 

Growth: 

vascular 

plants

NA

EC50 > 1.39 μg 

a.i./L NOAEC = 

1.39 μg a.i./L

(MRID 47944031

Supplemental 

Quantitative)

NA No
-Page 101 of 126-

Appendix B. Sumary of Environmental Fate Data for Alpha-cypermethrin

835.2130 Aqueous Photolysis (MRID 48425003)

Citation: Concha, M., V. Zhixing., and B. Claude. 2001. BAS 310 I (Alphacypermethrin): 

Aqueous Photolysis. Unpublished study performed by 

PTRL West, Inc., Hercules, CA; sponsored and submitted by BASF Corporation, Research 

Triangle Park. NC. BASF Registration Document Number : AL-324-003. Study initiated 

August 4, 2000 and completed October 24, 2001. 

The aqueous phototransformation of [l4C]alpha-cypermethrin (BAS 310 I); Two radiolabeled test 

substances, (benzyI and cyclopropane labels) were studied at 21.8 ± 0.5°C in sterile aqueous 

buffered pH 5 (alpha-cypermethrin is hydrolytically stable at this pH) solutions (0.01M acetate) 

that were continuously irradiated using a Xenon arc lamp for 15 days and 28 days, respectively. 

Recoveries were acceptable and ranged from 90 – 113% of the applied radiation. Two major 

degradates were observed, CL 206969 (3-phenoxybenzaldehyde, max of 12.9% 4 DAT) and 

CL206128 (3-phenoxybenzoic acid, 22.5% 4 DAT). The reviewer-calculated 

phototransformation half-life of BAS310 I (avg; both labels) was 1.7 days which is equivalent to 

4.84 days for a latitude of 40°N during the spring season. This study is classified as acceptable.

835.2120 Hydrolysis (MRID 48425001)

Citation:

The hydrolysis of FASTAC (WL85871; alpha-cypermethrin) at pH's 5, 7 and 9 have been 

measured in buffer solutions containing 1M acetone. Single first-order half –lives ranged from 

2.9 h at pH 9 to 162 days at pH 5 (22°C). Major degradated included cyclopropane carboxylic 

acid (WL42640) and meta-phenoxybenzaldehyde. This study is classified as unacceptable for the 

following scientific reasons: No indication that the study was conducted in the dark; it was not 

specified that the buffer solutions were sterile; therefore, it could not be determined if 

degradation was due to hydrolysis of biotic process; the test material was not characterized; 

degradation curves and regression analysis were not provided; Limits of Detection (LOD) and 

Limits of Quantification (LOQ) were not reported; the study author indicated (p. 9) that there is a 

An Arrhenius plot for each pH. No such plots were found in study.

MRID 48425002

Citation: 

The abiotic hydrolysis of 14C-alpha-cypermethrin at 0.0011 pg/ml was investigated in sterile 

aqueous buffered solutions at pH 4 , 7, and 9 at 25 and 50°C. For the 50°C study, first-order halflives were calculated. Alpha-cypermethrin was stable at pH 4, not determined at pH 7, and 

degraded with a half-life of 3.0 days in pH 9 buffered solution. In the 25°C study, first-order 

degradation half-lives were calculated for pH 7, and 9 buffered solutions as 67 and 3.5 days, 

respectively (half-lives were not determined for pH 4). In the aqueous solution at pH 4, only the 

parent compound was found until 10 days of incubation at 50 °C, indicating that alpha-
-Page 102 of 126-

cypermethrin was stable to hydrolysis at acidic pH. This study is classified as acceptable.

835.1230 Batch Equilibrium, Adsorption/desorption

Citation: A.D. Hill. 1993. [Benzyl- C] WL85875 (Fastac): Adsorption/Desorption In Three 

Soils. Unpublished study performed and sponsored by BASF Corporation, Agricultural 

Products, Research Triangle Park; BASF Number AL-620-011. Experimental start date 18th 

March 1993, and experimental completion date 21st May 1993. Study completion date October 

12, 1993.

The adsorption and desorption characteristics of FASTAC (14-C alpha-cypermethrin) in three 

soils were studied in a batch equilibrium experiment (in a sand [pH 6.7, organic carbon 0.6%], a 

sandy loam soil [pH 7. 1, organic carbon 1.8%], and a silty clay soil [pH 6.8, organic carbon 

3.1%]. The experiment was conducted in accordance with USEPA Subdivision N, Chemistry: 

Environmental Fate, Section 163-1: Leaching and Adsorption/Desorption Studies. Mean 

adsoption Kd’s were 868, 1042, and 821, corresponding mean Koc’s were 144,662, 57,889, and 

26,492 for the sand, sandy loam and silty clay, respectively. This study is classified as 

supplemental and upgradeable upon the submission of additional information related to 

classification of soils used in this study, in accordance to FAO Soil Classification (i.e. Soil Units) 

or equivalent U.S. Soil Taxonomy. 

835.4300 Aerobic Aquatic Metabolism

CITATION: Mamouni, A. 1993. Fastac (Benzyl14C): Degradation and Metabolism in Aquatic 

Systems. Unpublished study performed by RCC Umweltchemie AG, Switzerland, and 

sponsored by BASF Corporation, Agricultural Products. North Carolina, USA. Report Series: 

AL-630-011. Experiment start date February 11, 1992; completion date February 22, 1993. 

Final report issued October 18, 1993.

The biotransformation of FASTAC (Benzyl14C, labeled) i.e. l:l mixture of (S)-alpha-cyano-3-

phenoxybenzyl-(lR,3R)-3-(2,2- dichloroviny1)-2,2-d1methylcydopropanecarboxylate and (R)-

alpha-cyano-3- phenoxybenzyl-(lS,3S)-3-(2,2-dich1orovinyl)-2,2-

dimethy1cyclopropanecarboxylate (radiochemical purity ≥99.8%) was evaluated in two 

water/sediment systems. 

System I : Rhine-river water + Rhine loamy sand sediment (water: pH 8.2, total carbon 9.3; 

sediment: pH 7.8, total organic carbon 0.9); and 

System II : Pond water + Pond sandy clay sediment (water: pH 7.2, total carbon 9.3; 

sediment: pH 7.1, total organic carbon 5.4). 

Alpha-cypermethrin degraded at different rates in two aquatic systems with first-order half-lives 

of 45 and 18.2 days in the Rhine river, and in the pond aquatic system, respectively. The amount 

of the non-extractable radioactivity was greater in the pond system than in the Rhine system. 

After 30 days of incubation time, the non-extractable component amounted to 37.3 and 20.5% of 

total applied radioactivity for the pond and Rhine-river sediment, respectively. Overall 
-Page 103 of 126-

recoveries were acceptable. This study is classified supplemental. The drainage area contributing 

to the soucres of water used in the study were not appropriately characterized; the sediments 

used in the study were not classified according to the FAO or WRB classification scheme.; and 

the experiments were conducted in systems with neutral to alkaline conditions that may favor 

more rapid hydrolysis therefore the results are of uncertain significance.

Terrestrial Field Dissipation Studies 

MRIDs 48425014, 48425015, 48425016 (UK)

Alpha-cypermethrin residues in the field were studied in soils plots in the UK over a three year 

period from 1981-1983; applications of alpha-cypermethrin were made a single time each year. 

Over the three years of the trial there was no indication of a build-up of FASTAC residues in the 

surface soil layers, or any evidence to suggest that the compound is leached into sub-surface soil 

layers. This study was not conducted in accordance with EPA- Terrestrial Field Dissipation 

guideline 835-6100. The submitter of this study was neither the sponsor of this study nor 

conducted it, and does not know whether it has been conducted in accordance with 40 CFR Part 

160. These are significant limitations of the study, thus is classified as unacceptable. 

MRIDs 48425017, 48425018, 48425019 (Hoath)

Residues in the field were studied in soils plots in the UK over a three year period from 1981-

1983 to study the decay of FASTAC (alpha-cypermethrin) in a clay loam soil. A second 

application of pesticide was made to the same trial plots in 1982 and a. third application in 1983. 

In all cases the compound was applied to bare soil, as a diluted EC formulation, at a rate of 0.5 

kg ai/ha. Samples of soil were then taken at various intervals up to 52 weeks after application 

and analyzed for residues of FASTAC. Over the three years of the trial there was no indication of 

a build-up of FASTAC residues in the surface soil layers, or any evidence to suggest that the 

compound is leached into sub-surface soil layers. This study was not conducted in accordance 

with EPA- Terrestrial Field Dissipation guideline 835-6100. The submitter of this study was 

neither the sponsor of this study nor conducted it, and does not know whether it has been 

conducted in accordance with 40 CFR Part 160. These are significant limitations of the study, 

thus is classified as unacceptable. 

MRIDs 48425020, 48425021, 48425022 (Coates)

Residues in the field were studied in soils plots in the UK over a three year period from 1981-

1983 to study the decay of FASTAC (alpha-cypermethrin) in silty clay soil. Alphacypermethrin was applied annually at the same trial plots for three years, as a diluted EC 

formulation, at a dosage rate of U.5 kg ai/ha. Over the three years of the trial there was no 

indication of a build-up of FASTAC residues in the surface soil layers, or any evidence to 

suggest that significant leaching of the compound into sub-surface soil layers was occurring. 

This study was not conducted in accordance with EPA- Terrestrial Field Dissipation guideline 

835-6100. The submitter of this study was neither the sponsor of this study nor conducted it, and 

does not know whether it has been conducted in accordance with 40 CFR Part 160. These are 

significant limitations of the study, thus is classified as unacceptable. 
-Page 104 of 126-

Appendix C. Aquatic Model Input/Output Data.

Example Input/Output Data for Individual Simulations

PRZM/EXAMS Example Input/Output File.

stored as alphacyp_citrus.out

Chemical: alpha-cypermethrin

PRZM environment: FLcitrusSTD.txt modified Tueday, 29 May 2007 at 13:45:56

EXAMS environment: pond298.exv modified Tueday, 26 August 2008 at 06:14:08

Metfile: w12844.dvf modified Tueday, 26 August 2008 at 06:14:22

Water segment concentrations (ppb)

Year Peak 96 hr 21 Day 60 Day 90 Day Yearly

1961 0.04266 0.01229 0.007847 0.005455 0.004836 0.001544

1962 0.07194 0.02487 0.0108 0.007519 0.007241 0.00232

1963 0.1423 0.04125 0.01212 0.00788 0.006535 0.002472

1964 0.1516 0.04229 0.01521 0.01086 0.008799 0.003551

1965 0.108 0.04521 0.0156 0.008026 0.006894 0.003201

1966 0.1102 0.04441 0.01426 0.01072 0.01026 0.003436

1967 0.07331 0.02622 0.01012 0.007551 0.006701 0.002663

1968 0.1677 0.04651 0.01368 0.01085 0.009087 0.003614

1969 0.07825 0.02448 0.0113 0.00851 0.007652 0.003152

1970 0.04281 0.01267 0.006276 0.00532 0.005084 0.001943

1971 0.04341 0.01714 0.008061 0.005764 0.005746 0.002109

1972 0.1413 0.0407 0.01765 0.01004 0.008651 0.002885

1973 0.05575 0.01609 0.009127 0.00763 0.006709 0.00231

1974 0.1088 0.03047 0.01109 0.007645 0.00669 0.002517

1975 0.1031 0.02988 0.0137 0.007285 0.006687 0.002354

1976 0.07483 0.02532 0.01244 0.008962 0.007301 0.002519

1977 0.1652 0.05703 0.02101 0.01036 0.00822 0.002838

1978 0.05004 0.01834 0.009283 0.007076 0.006267 0.002497

1979 0.1235 0.05793 0.02307 0.01131 0.00889 0.003203

1980 0.1381 0.03805 0.01275 0.007833 0.006515 0.002176

1981 0.1256 0.04125 0.01619 0.01067 0.00847 0.002888

1982 0.07641 0.0266 0.01126 0.007332 0.006834 0.00284

1983 0.07625 0.02516 0.009221 0.00695 0.006354 0.002616

1984 0.06929 0.02281 0.008414 0.007028 0.006439 0.002684

1985 0.04621 0.01758 0.01165 0.00822 0.007199 0.002352

1986 0.07898 0.02206 0.009262 0.007053 0.006489 0.002348

1987 0.07018 0.0206 0.01032 0.006785 0.005832 0.002631

1988 0.1902 0.05364 0.02023 0.01222 0.01006 0.003155

1989 0.04615 0.01614 0.006879 0.005485 0.00505 0.00161

1990 0.09643 0.02848 0.0126 0.009444 0.008954 0.002884

Sorted results

Prob. Peak 96 hr 21 Day 60 Day 90 Day Yearly

0.032258064516129 0.1902 0.05793 0.02307 0.01222 0.01026 0.003614

0.0645161290322581 0.1677 0.05703 0.02101 0.01131 0.01006 0.003551

0.0967741935483871 0.1652 0.05364 0.02023 0.01086 0.0090870.003436

0.129032258064516 0.1516 0.04651 0.01765 0.01085 0.0089540.003203

0.161290322580645 0.1423 0.04521 0.01619 0.01072 0.00889 0.003201

0.193548387096774 0.1413 0.04441 0.0156 0.01067 0.0087990.003155

0.225806451612903 0.1381 0.04229 0.01521 0.01036 0.0086510.003152
-Page 105 of 126-

0.258064516129032 0.1256 0.04125 0.01426 0.01004 0.00847 0.002888

0.290322580645161 0.1235 0.04125 0.0137 0.0094440.00822 0.002885

0.32258064516129 0.1102 0.0407 0.01368 0.0089620.0076520.002884

0.354838709677419 0.1088 0.03805 0.01275 0.00851 0.0073010.00284

0.387096774193548 0.108 0.03047 0.0126 0.00822 0.0072410.002838

0.419354838709677 0.1031 0.02988 0.01244 0.0080260.0071990.002684

0.451612903225806 0.09643 0.02848 0.01212 0.00788 0.0068940.002663

0.483870967741936 0.07898 0.0266 0.01165 0.0078330.0068340.002631

0.516129032258065 0.07825 0.02622 0.0113 0.0076450.0067090.002616

0.548387096774194 0.07641 0.02532 0.01126 0.00763 0.0067010.002519

0.580645161290323 0.07625 0.02516 0.01109 0.0075510.00669 0.002517

0.612903225806452 0.07483 0.02487 0.0108 0.0075190.0066870.002497

0.645161290322581 0.07331 0.02448 0.01032 0.0073320.0065350.002472

0.67741935483871 0.07194 0.02281 0.01012 0.0072850.0065150.002354

0.709677419354839 0.07018 0.02206 0.0092830.0070760.0064890.002352

0.741935483870968 0.06929 0.0206 0.0092620.0070530.0064390.002348

0.774193548387097 0.05575 0.01834 0.0092210.0070280.0063540.00232

0.806451612903226 0.05004 0.01758 0.0091270.00695 0.0062670.00231

0.838709677419355 0.04621 0.01714 0.0084140.0067850.0058320.002176

0.870967741935484 0.04615 0.01614 0.0080610.0057640.0057460.002109

0.903225806451613 0.04341 0.01609 0.0078470.0054850.0050840.001943

0.935483870967742 0.04281 0.01267 0.0068790.0054550.005050.00161

0.967741935483871 0.04266 0.01229 0.0062760.00532 0.0048360.001544

0.1 0.16384 0.052927 0.019972 0.010859 0.0090737 0.0034127

Average of yearly averages: 0.00264373333333333

Inputs generated by pe5.pl - Novemeber 2006

Data used for this run:

Output File: alphacyp_citrus

Metfile: w12844.dvf

PRZM scenario: FLcitrusSTD.txt

EXAMS environment file: pond298.exv

Chemical Name: alpha-cypermethrin

Description Variable Name Value Units Comments

Molecular weightmwt 416.3 g/mol

Henry's Law Const. henry 3.4e-7 atm-m^3/mol

Vapor Pressure vapr 2.5e-9 torr

Solubility sol 0.004 mg/L

Kd Kd mg/L

Koc Koc 141700 mg/L

Photolysis half-life kdp 36.2 days Half-life

Aerobic Aquatic Metabolism kbacw 10.7 days Halfife

Anaerobic Aquatic Metabolism kbacs 18.1 days Halfife

Aerobic Soil Metabolism asm 61 days Halfife

Hydrolysis: pH 7 0 days Half-life

Method: CAM 2 integer See PRZM manual

Incorporation Depth: DEPI 0 cm

Application Rate:TAPP 0.028 kg/ha

Application Efficiency: APPEFF0.95 fraction

Spray Drift DRFT 0.039 fraction of application rate applied to pond

Application Date Date 01-06 dd/mm or dd/mmm or dd-mm or dd-mmm

Interval 1 interval 14 days Set to 0 or delete line for single app.

app. rate 1 apprate 0.028 kg/ha

Interval 2 interval 14 days Set to 0 or delete line for single app.
-Page 106 of 126-

app. rate 2 apprate 0.028 kg/ha

Interval 3 interval 14 days Set to 0 or delete line for single app.

app. rate 3 apprate 0.028 kg/ha

Interval 4 interval 14 days Set to 0 or delete line for single app.

app. rate 4 apprate 0.028 kg/ha

Interval 5 interval 14 days Set to 0 or delete line for single app.

app. rate 5 apprate 0.028 kg/ha

Interval 6 interval 14 days Set to 0 or delete line for single app.

app. rate 6 apprate 0.028 kg/ha

Interval 7 interval 14 days Set to 0 or delete line for single app.

app. rate 7 apprate 0.028 kg/ha

Record 17: FILTRA

IPSCND1

UPTKF

Record 18: PLVKRT

PLDKRT

FEXTRC 0.5

Flag for Index Res. Run IR EPA Pond

Flag for runoff calc. RUNOFF none none, monthly or total(average of entire run)
-Page 107 of 126-

Appendix D. Model Outputs

SIP Model Outputs

Table 1. Inputs

Parameter Value

Chemical name Alpha-cypermethrin

Solubility (in water at 25oC; mg/L) 4.00E-03

Mammalian LD50 (mg/kg-bw) 86

Mammalian test species laboratory rat

Body weight (g) of "other" mammalian 

species

Mammalian NOAEL (mg/kg-bw) 100

Mammalian test species laboratory rat

Body weight (g) of "other" mammalian 

species

Avian LD50 (mg/kg-bw) 2025

Avian test species northern bobwhite quail

Body weight (g) of "other" avian species

Mineau scaling factor 1.15

Mallard NOAEC (mg/kg-diet) 50

Bobwhite quail NOAEC (mg/kg-diet) 50

NOAEC (mg/kg-diet) for other bird species 0

Body weight (g) of other avian species

NOAEC (mg/kg-diet) for 2nd other bird 

species 0

Body weight (g) of 2nd other avian species

Table 2. Mammalian Results

Parameter Acute Chronic

Upper bound exposure (mg/kg-bw) 0.0007 0.0007

Adjusted toxicity value (mg/kg-bw) 66.1478 76.9161

Ratio of exposure to toxicity 0.0000 0.0000

Conclusion*

Drinking water exposure 

alone is NOT a potential 

concern for mammals

Drinking water exposure 

alone is NOT a potential 

concern for mammals

Table 3. Avian Results

Parameter Acute Chronic
-Page 108 of 126-

Upper bound exposure (mg/kg-bw) 0.0032 0.0032

Adjusted toxicity value (mg/kg-bw) 1458.8698 2.4806

Ratio of exposure to acute toxicity 0.0000 0.0013

Conclusion*

Drinking water exposure 

alone is NOT a potential 

concern for birds

Drinking water exposure 

alone is NOT a potential 

concern for birds

*Conclusion is for drinking water exposure alone. This does not combine all routes of exposure. 

Therefore, when aggregated with other routes (i.e., diet, inhalation, dermal), pesticide exposure through 

drinking water may contribute to a total exposure that has potential for effects to non-target animals.

STIR Model Outputs

Welcome to the EFED 

Screening Tool for Inhalation Risk

This tool is designed to provide the risk assessor with a rapid method for determining the potential

significance of the inhalation exposure route to birds and mammals in a risk assessment.

Input

Application and Chemical Information

Enter Chemical Name

Alphacypermethrin

Enter Chemical Use

Is the Application a Spray? (enter y or n) y

If Spray What Type (enter ground or air) air

Enter Chemical Molecular Weight (g/mole) 416.3

Enter Chemical Vapor Pressure (mmHg) 2.50E-09

Enter Application Rate (lb a.i./acre) 0.025

Toxicity Properties

Bird

Enter Lowest Bird Oral LD50 (mg/kg bw) 2025

Enter Mineau Scaling Factor 1.15

Enter Tested Bird Weight (kg) 0.178

Mammal

Enter Lowest Rat Oral LD50 (mg/kg bw) 86

Enter Lowest Rat Inhalation LC50 (mg/L) 2.5

Duration of Rat Inhalation Study (hrs) 4

Enter Rat Weight (kg) 0.35

Output
-Page 109 of 126-

Results Avian (0.020 kg )

Maximum Vapor Concentration in Air at Saturation 

(mg/m3) 5.60E-05

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 7.04E-06

Adjusted Inhalation LD50 3.28E+02

Ratio of Vapor Dose to Adjusted Inhalation LD50 2.15E-08 Exposure not Likely Significant

Maximum Post-treatment Spray Inhalation Dose (mg/kg) 2.40E-03

Ratio of Droplet Inhalation Dose to Adjusted Inhalation 

LD50 7.32E-06 Exposure not Likely Significant

Results Mammalian (0.015 kg )

Maximum Vapor Concentration in Air at Saturation 

(mg/m3) 5.60E-05

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 8.85E-06

Adjusted Inhalation LD50 1.49E+02

Ratio of Vapor Dose to Adjusted Inhalation LD50 5.95E-08 Exposure not Likely Significant

Maximum Post-treatment Spray Inhalation Dose (mg/kg) 3.02E-03

Ratio of Droplet Inhalation Dose to Adjusted Inhalation 

LD50 2.03E-05 Exposure not Likely Significant

KABAM Model Outputs

*Predicted concentrations of alpha-cypermethrin in fish assume measured uptake (K1= 

208) and elimination (K2 = 0.58) rate constants from the submitted bluegill sunfish BCF 

study (MRID 42868203). 

Table 11. Estimated concentrations of Alpha-cypermethrin in ecosystem components.

Ecosystem Component

Total 

concentration 

(μg/kg-ww)

Lipid 

normalized 

concentration 

(μg/kg-lipid)

Contribution 

due to diet 

(μg/kg-ww)

Contribution 

due to 

respiration 

(μg/kg-ww)

Water (total)* 0 N/A N/A N/A

Water (freely dissolved)* 0 N/A N/A N/A

Sediment (pore water)* 0 N/A N/A N/A

Sediment (in solid)** 28 N/A N/A N/A

Phytoplankton 2,067 103357 N/A 2,067.14

Zooplankton 3,154 105132 828.34 2,325.61

Benthic Invertebrates 4,553 151770 2,520.62 2,032.49

Filter Feeders 2,983 149138 1,635.96 1,346.80

Small Fish 268 6711 258.24 10.22

Medium Fish 125 3120 114.55 10.24

Large Fish 15 373 4.21 10.70

* Units: μg/L; **Units: μg/kg-dw
-Page 110 of 126-

Table 12. Total BCFand BAF values of Alpha-cypermethrin in 

aquatic trophic levels.

Trophic Level

Total BCF 

(μg/kgww)/(μg/L)

Total BAF 

(μg/kgww)/(μg/L)

Phytoplankton 120571 68905

Zooplankton 85907 105132

Benthic Invertebrates 89911 151770

Filter Feeders 59098 99425

Small Fish 344 8949

Medium Fish 344 4160

Large Fish 359 497

Table 13. Lipid-normalized BCF, BAF, BMF and BSAF values of Alpha-cypermethrin in 

aquatic trophic levels.

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

Zooplankton Benthic 

Invertebrates

Filter Feeders Small Fish Medium Fish Large Fish

Concentration (μg/kg)

Trophic Level

Figure 1. Total pesticide concentration 

per trophic level

Contribution due to respiration (μg/kg-ww)

Contribution due to diet (μg/kg-ww)
-Page 111 of 126-

Trophic Level

BCF 

(μg/kglipid)/(μg/L)

BAF 

(μg/kglipid)/(μg/L)

BMF 

(μg/kglipid)/(μg/kglipid)

BSAF 

(μg/kglipid)/(μg/kgOC)

Phytoplankton 6028572 3445235 N/A 146

Zooplankton 2863579 3504387 1.02 148

Benthic Invertebrates 2997019 5059010 2.21 214

Filter Feeders 2954909 4971271 2.17 210

Small Fish 8592 223716 0.05 9

Medium Fish 8592 103989 0.04 4

Large Fish 8966 12422 0.12 1

Table 14. Calculation of EECs for mammals and birds consuming fish contaminated by Alphacypermethrin.

Wildlife Species Biological Parameters EECs (pesticide intake)

Body

Weight

(kg)

Dry Food 

Ingestion 

Rate (kg-dry 

food/kgbw/day)

Wet Food 

Ingestion 

Rate (kg-wet 

food/kgbw/day)

Drinking 

Water

Intake

(L/d)

Dose Based 

(mg/kgbw/d)

Dietary 

Based 

(ppm)

Mammalian

fog/water shrew 0.02 0.140 0.585 0.003 2.665 4.55

rice rat/star-nosed 

mole 0.1 0.107 0.484 0.011 1.268 2.62

small mink 0.5 0.079 0.293 0.048 0.037 0.12

large mink 1.8 0.062 0.229 0.168 0.029 0.12

small river otter 5.0 0.052 0.191 0.421 0.024 0.12

large river otter 15.0 0.042 0.157 1.133 0.002 0.01

Avian

sandpipers 0.0 0.228 1.034 0.004 2.6654 2.58

cranes 6.7 0.030 0.136 0.211 0.3437 2.53

rails 0.1 0.147 0.577 0.010 1.3919 2.41

herons 2.9 0.040 0.157 0.120 0.3682 2.34

small osprey 1.3 0.054 0.199 0.069 0.0249 0.12

white pelican 7.5 0.029 0.107 0.228 0.0016 0.01
-Page 112 of 126-

Table 15. Calculation of toxicity values for mammals and birds consuming 

fish contaminated by Alpha-cypermethrin.

Wildlife Species

Toxicity Values

Acute Chronic

Dose 

Based 

(mg/kgbw)

Dietary 

Based 

(mg/kg-diet)

Dose Based 

(mg/kg-bw)

Dietary 

Based 

(mg/kg-diet)

Mammalian

fog/water shrew 180.59 N/A 10.50 100

rice rat/star-nosed 

mole 122.51 N/A 7.12 100

small mink 80.76 N/A 4.70 100

large mink 57.11 N/A 3.32 100

small river otter 44.24 N/A 2.57 100

large river otter 33.61 N/A 1.95 100

Avian

sandpipers 1458.87 4690.00 N/A 50

cranes 3489.58 4690.00 N/A 50

rails 1760.46 4690.00 N/A 50

herons 3077.67 4690.00 N/A 50

small osprey 2712.68 4690.00 N/A 50

white pelican 3549.12 4690.00 N/A 50

Table 16. Calculation of RQ values for mammals and birds consuming fish 

contaminated by Alpha-cypermethrin.

Wildlife Species

Acute Chronic

Dose 

Based

Dietary 

Based

Dose Based Dietary 

Based

Mammalian

fog/water shrew 0.015 N/A 0.254 0.046

rice rat/star-nosed 

mole 0.010 N/A 0.178 0.026

small mink 0.000 N/A 0.008 0.001

large mink 0.001 N/A 0.009 0.001
-Page 113 of 126-

small river otter 0.001 N/A 0.009 0.001

large river otter 0.000 N/A 0.001 0.000

Avian

sandpipers 0.002 0.001 N/A 0.052

cranes 0.000 0.001 N/A 0.051

rails 0.001 0.001 N/A 0.048

herons 0.000 0.000 N/A 0.047

small osprey 0.000 0.000 N/A 0.002

white pelican 0.000 0.000 N/A 0.000

T-REX Model Outputs

Summary of Risk Quotient Calculations Based on Upper Bound Kenaga EECs

Table X. Upper Bound Kenaga, Acute Avian Dose-Based Risk Quotients

Size 

Class

(grams)

Adjuste

d

LD50

EECs and RQs

Short Grass Tall Grass Broadleaf Plants/

Small Insects

Fruits/Pods/

Seeds/

Large Insects

Granivore

EEC RQ EEC RQ EEC RQ EEC RQ

EE

C RQ

20 1440.86 17.96 0.01 8.23 0.01 10.10 0.01 1.12 0.00 0.25

0.0

0

100 1834.29 10.24 0.01 4.69 0.00 5.76 0.00 0.64 0.00 0.14

0.0

0

1000 2591.00 4.59 0.00 2.10 0.00 2.58 0.00 0.29 0.00 0.06

0.0

0

Table X. Upper Bound Kenaga, Subacute Avian Dietary Based Risk Quotients

LC50

EECs and RQs

Short Grass Tall Grass

Broadleaf 

Plants/

Small Insects

Fruits/Pods/

Seeds/

Large Insects
-Page 114 of 126-

EEC RQ

EE

C RQ

EE

C RQ EEC RQ

2634 15.77 0.01 7.23 0.00 8.87 0.00 0.99 0.00

Size class not used for dietary risk quotients 

Table X. Upper Bound Kenaga, Chronic Avian Dietary Based Risk Quotients

NOAE

C 

(ppm)

EECs and RQs

Short Grass Tall Grass

Broadleaf 

Plants/

Small Insects

Fruits/Pods/

Seeds/

Large Insects

EEC RQ

EE

C RQ

EE

C RQ EEC RQ

50 15.77 0.32 7.23 0.14 8.87 0.18 0.99 0.02

Size class not used for dietary risk quotients

Table X. Upper Bound Kenaga, Acute Mammalian Dose-Based Risk Quotients 

Size 

Class

(grams)

Adjuste

d

LD50

EECs and RQs

Short Grass Tall Grass Broadleaf Plants/

Small Insects

Fruits/Pods/

Seeds/

Large Insects

Granivore

EEC RQ EEC RQ EEC RQ EEC RQ

EE

C RQ

15 189.01 15.04 0.08 6.89 0.04 8.46 0.04 0.94 0.00 0.21

0.0

0

35 152.93 10.39 0.07 4.76 0.03 5.85 0.04 0.65 0.00 0.14

0.0

0

1000 66.15 2.41 0.04 1.10 0.02 1.36 0.02 0.15 0.00 0.03

0.0

0

Table X. Upper Bound Kenaga, Acute Mammalian Dietary Based Risk Quotients

LC50 

(ppm)

EECs and RQs

Short Grass Tall Grass

Broadleaf 

Plants/

Small Insects

Fruits/Pods/

Seeds/

Large Insects

EEC RQ

EE

C RQ

EE

C RQ EEC RQ

0 15.77

####

# 7.23

####

# 8.87

#DIV/0

! 0.99

####

#

Size class not used for dietary risk quotients
-Page 115 of 126-

Table X. Upper Bound Kenaga, Chronic Mammalian Dietary Based Risk 

Quotients

NOAE

C 

(ppm)

EECs and RQs

Short Grass Tall Grass

Broadleaf 

Plants/

Small Insects

Fruits/Pods/

Seeds/

Large Insects

EEC RQ

EE

C RQ

EE

C RQ EEC RQ

100 15.77 0.16 7.23 0.07 8.87 0.09 0.99 0.01

Size class not used for dietary risk quotients 

Table X. Upper Bound Kenaga, Chronic Mammalian Dose-Based Risk Quotients

Size 

Class

(grams)

Adjuste

d 

NOAEL

EECs and RQs

Short Grass Tall Grass Broadleaf Plants/

Small Insects

Fruits/Pods/

Seeds/

Large Insects

Granivore

EEC RQ EEC RQ EEC RQ EEC RQ

EE

C RQ

15 10.99 15.04 1.37 6.89 0.63 8.46 0.77 0.94 0.09 0.21

0.0

2

35 8.89 10.39 1.17 4.76 0.54 5.85 0.66 0.65 0.07 0.14

0.0

2

1000 3.85 2.41 0.63 1.10 0.29 1.36 0.35 0.15 0.04 0.03

0.0

1
-Page 116 of 126-

Appendix E. Reported Ecological Incidents for Racemic and Zeta-Cypermethrin in EIIS. 

Table E-1. Cypermethrin and Zeta-Cypermethrin Incident Report Summaries

Incident # Organism(s) 

Affected

Certainty of 

Involvement

Legality of 

Use Description

I008737-

001

Lobster (Decapoda) Probable Registered 

Use

In a 5000 gal. saltwater tank in 

Cocoa Beach, FL 32931, an 

owner, 

Rancher/Breeder/Farmer found 

800 lobsters dead and another 

25 lobsters still alive in the 

tank. He used a product (EPA 

Reg. No. 4822-452): RAID 

Concentrate - Deep Reach 

Fogger in a room adjacent to 

the tank room then closed the 

tank room door for the night, 

but did not place a towel under 

the door. An air conditioner 

was turned off. He does not 

have UV/ozone sterilization. 

He has added another 200-300 

lobsters to this same tank and 

they seem fine. He has tested

water, ammonia nitrites, 

nitrate, pH and all are within 

normal limits. He could not 

locate the EPA Reg. No. on the 

container.

I009966-

002

Bass (Micropterus 

spp.)

Bluegill (Lepmis 

macrochirus)

Carp (Cyprinus 

carpio)

Catfish (Ictaluridae)

Crappie 

(Centrarchidae)

Minnow 

(Cyprinidae)

Shad (Clupeidae)

Probable Misuse A fish kill was reported on 

February 9, 1998 in 

Chattanooga, the result of a 

termiticide containing 

cypermethrin entering Rogers 

Branch and its un-named 

tributaries. The Tennessee 

Wildlife Resources 

Association assessed the cost 

of the dead fish at $609.33. 

Civil penalties and damages 

were assessed, suggesting 

misuse of the pesticide.

Further information was 

provided by a 6(a)(2) report 

from Zenaca Ag Products 
-Page 117 of 126-

Table E-1. Cypermethrin and Zeta-Cypermethrin Incident Report Summaries

Incident # Organism(s) 

Affected

Certainty of 

Involvement

Legality of 

Use Description

(I006971-001). They claim 

that their investigation indicate 

that the kill was not likely the 

result of any labeled use of 

Demon TC or of the minor 

spill reported on the property 

in November - December 

1997. They claim the 

exposure characteristics 

suggest "introduction of 

relatively massive amounts of 

chemical directly into the 

water course.

I011346-

001

Crayfish (Decapoda) Highly probable Misuse According to a report from the 

Environment Agency - UK, 

thousands of crayfish had been 

killed in the Sherston Avon at 

Pinkney, upstream of 

Malmesbury, Wiltshire. 

Within 24 hours of the first 

report, the Environment 

Agency's Exeter laboratory 

pinpointed cypermethrin as the 

cause. An investigation led to 

the Badminton sewage 

treatment works and, 

ultimately, to a kennel where a 

sheep dip called Crovert 

(containing cypermethrin) had 

been used to treat hounds for 

mange. After treatment, the 

Crovert was washed off and 

entered the river through the 

effluent of the sewage 

treatment plant. 

I001031-

001

Bluegill (Lepmis 

macrochirus)

Carp (Cyprinus 

carpio)

Catfish (Ictaluridae)

Largemouth bass 

(Micropterus 

salmoides)

Highly probable Undetermined This fish kill resulted from the 

application of Demon TC as a 

termite barrier around a home 

in Henderson, Kentucky. 

Underground drainage tile had 

been installed around the home 

to divert water to a pond 50 

feet away, and the night 
-Page 118 of 126-

Table E-1. Cypermethrin and Zeta-Cypermethrin Incident Report Summaries

Incident # Organism(s) 

Affected

Certainty of 

Involvement

Legality of 

Use Description

following the application of 

Demon there was a heavy 

rainfall which resulted in 

dumping some of the Demon 

into the pond. Approximately 

44 fish we re killed.

I018158-

017

Koi (Cyprinus 

carpio)

Probable Undetermined Koi allegedly died from a drift 

exposure caused by an Eagle 

Pest Control technician 

performing a routine quarterly 

perimeter treatment using the 

labeled rate of Probuild TC 

(a.i. cypermethrin). Koi fish 

pond was located at the 

backyard of the treatment 

location.

I017029-

001

Unknown fish Highly probable Misuse 

(Accidental)

This is an update of a previous 

incident that occurred in 

Takoma Park, MD, in which a 

cypermethrin-based pesticide 

called "Prevail" spilled from 

one of the company's pesticide 

application trucks onto a 

driveway while an employee 

was attempting to repair or 

replace a pump. The employee 

used a hose to wash off the 

driveway, causing the pesticide 

to drain into a creek and, 

subsequently, into Chesapeake 

Bay. A large number of fish 

were killed as the result of this 

incident.The pest control 

company was fined $7,300 and 

its license was suspended for 4 

years as a part of the consent 

agreement with the Maryland 

Department of Agriculture.

I006971-

001

Unknown fish Highly probable Undetermined Zeneca reported that 

Tennessee Dept. of Agriculture 

was contacted about fish kill in 

several small ponds fed by a 

small stream. State 
-Page 119 of 126-

Table E-1. Cypermethrin and Zeta-Cypermethrin Incident Report Summaries

Incident # Organism(s) 

Affected

Certainty of 

Involvement

Legality of 

Use Description

investigators estimated 2,200 

dead fish (i.e., bass, bluegill, 

shad) were impacted along 

with various other unspecified 

aquatic organisms. Soil and 

water samples were obtained. 

Analysis showed trace levels 

of chlorpyrifos and permethrin, 

and exceptionally high levels 

of cypermethrin.

Initial investigation focused on 

a local pest control applicator. 

A multi-agency investigation 

team later focused its attention 

to alternative explanations.

I007107-

003

Minnow 

(Cyprinidae)

Highly probable Undetermined This incident is one of the 

incidents stated on a 

consolidated report submitted 

by the Pesticide Investigation 

Unit, California Dept. of Fish 

and Game for the year 1997. 

One thousand Gambusia 

(minnows) reported dead in 

Placer County on 2-7-1997. 

The PIU confirmed that 

Cypermethrin was the cause of 

this fish kill.

I010444-

004

N/R Probable Misuse 

(Accidental)

To comply with 6(a)2 

regulations, FMC reported an 

incident that occurred in Silver 

Spring, MD (the location was 

not given in the report but was 

known to this writer). A 

treatment tank was being

cleaned out by an applicator 

and the washings entered Rock 

Creek, causing a fish kill 

extending from an area near 

Walter Reed Hospital to the 

Potomac River. Initial 

estimates that there were 

between 1000 and 150,000 

dead fish but later, the estimate 
-Page 120 of 126-

Table E-1. Cypermethrin and Zeta-Cypermethrin Incident Report Summaries

Incident # Organism(s) 

Affected

Certainty of 

Involvement

Legality of 

Use Description

was revised to 10,000. The 

Maryland Dept. of Agricuoture 

found 50 ppb cypermethrin in 

the water.

I013857-

011

Unknown fish Probable Misuse 

(Intentional)

To comply with 6(a)2

requirements, Syngenta 

reported that the February 25, 

2003, issue of the Independent 

(London) carried an account of 

a large fish kill in the river 

Slea, in Lincolnshire. 

According to this newspaper, 

someone had dumped 

Cypermethrin into surface 

water drains at an industrial 

site, infecting 13 miles of the 

river and causing the death of 

100,000 fish.

I004876-

011

Crayfish (Decapoda)

Stonefly 

(Plecoptera)

Highly probable Misuse 

(Accidental)

This information was sent in 

response to a letter from 

Gerard Desir, EPA. It 

concerns a fish kill in the 

Salmon River as the result of 

cypermethrin poisoning.

I000011-

001

N/R Possible Registered 

Use

Pond fishkill via alleged 

underground stream under 

home, after termite control.

I015094-

001

Unknown fish Possible Registered 

Use

FMC 6(a)(2) incident report 

stated that a contractor applied 

Prevail (cypermethrin) on a 

horizontal soil surface where a 

concert slab was to be poured. 

Dead fish were found in a 

stream 1/2 to 1 mile from the 

construction site. No analyses 

were given.

I017984-

001

Crayfish (Decapoda) Possible Misuse 

(Accidental)

A web site from the UK 

reports that the joint mater of 

the Duke of Beaufort appeared 

at Avon magistrates on 

10/20/1998. He pleaded guilty 

to allowing hounds treated 

with cypermethrin, which is 
-Page 121 of 126-

Table E-1. Cypermethrin and Zeta-Cypermethrin Incident Report Summaries

Incident # Organism(s) 

Affected

Certainty of 

Involvement

Legality of 

Use Description

used to treat mange, to enter 

the River Avon. The pesticide 

killed around 10,000 

endangered white clawed 

crayfish in the river.

I011348-

001

Sparrow 

(Fringillidae)

Unlikely Undetermined A report on the Internet (Third 

World Network) described a 

massive killing of sparrows in 

a small village in Bangladesh 

as the result of a massive use 

of cypermethrin. In eggplant 

and pointed gourd fields there 

was a spraying of Ustad the 

night before. The sparrows ate 

insects that had died from the 

spraying and they, in turn, died 

by the thousands. An original 

estimate was that 5000 had 

died but later indications were 

that the number was much 

higher. Residents were 

shocked by the massive kill of 

these birds and protests were 

made against the use of 

pesticides.

I021456-

001

Bluegill (Lepomis 

macrochirus)

Largemouth bass 

(Micropterus 

salmoides)

Possible Undetermined Iowa Departmewnt of Natural 

Resources reported an incident 

on dozens of fish kill in a 

private pond surrounded by 

soybean field on three sides 

and live pasture field to the 

south in Iowa. There was aerial 

spraying of pesticides onto the 

soybean field.

I000340-

009

Goat (Bovidae) Possible Undetermined The report implied that an 

unspecified number of goats 

may have suffered illness due 

to nearby application of 

cypermethrin.

I000103-

010

Barred owl (Strix 

varia)

Mockingbird 

(Mimus polyglottos)

Unlikely Undetermined According to the investigative 

report 11 dead birds were 

found near a private dwelling 

(9 sparrows, a mockingbird, 
-Page 122 of 126-

Table E-1. Cypermethrin and Zeta-Cypermethrin Incident Report Summaries

Incident # Organism(s) 

Affected

Certainty of 

Involvement

Legality of 

Use Description

White-throated 

sparrow 

(Zonotrichea 

albicollis)

and a barred owl). It was 

suspected that the mortality 

was due to toxicosis. Four 

birds were selected for 

necropsy (1 mockingbird and 3 

sparrows). The premises had 

been periodically sprayed for 

termites for 8 years, the most 

recent being 2 month prior to 

the event with cypermethrin. 

Earlier treatments had been 

done with lindane. Analysis of 

brain ChE activity gave normal 

results. Residue analysis of 

gizzard/crop contents revealed 

the presence of Heptachlor 

Epoxide and a significant 

amount of Dieldrin. there was 

an insufficient amount of brain 

tissue left to make a residue 

analysis of the brain for 

Dieldrin. According to the 

report brain tissue residue of 

1ppm is considered significant 

but body residues are usually 

many times greater than brain 

residue. The birds were 

observed to undergo 

convulsions just before dying. 

Crop/gizzard content residue 

analysis revealed Dieldrin at 

7480 ppb and Hrptachlor 

Epoxide at 710 ppb. There 

was no evidence of 

organophosphate, carbamate, 

lindane, or cypermethrin 

pesticides.

I000340-

006

Dog (Canis 

familiaris)

Possible Undetermined According to the investigative 

report, a dog was dipped and 

also exposed to pyrethroid 

products. The dog's illness 

was suspected to be due to one 

of these exposures.
-Page 123 of 126-

Table E-1. Cypermethrin and Zeta-Cypermethrin Incident Report Summaries

Incident # Organism(s) 

Affected

Certainty of 

Involvement

Legality of 

Use Description

I000340-

002

Cat (Felix 

domesticus)

Probable Registered 

Use

According to the report A cat 

was exposed to toxic fumes of 

cypermethrin by following 

applicator around as he 

worked.

I014202-

007

Honey Bee (Apis 

millifera)

Possible Registered 

Use

On Aug 9, 2002, a bee keeper 

reported that queenless hives 

was observed on Aug 8, 2002. 

Yard was inspected where 

there use to be 32 hives, but 

has declined to 26 hives. All 

26 hives were open and 

inspected. 8 of the hives were 

queenless or failing. No 

diseases were found, but 

Varroa mite was positive for 

one hive. An erratic or spotty 

brood pattern was common. 

Pesticide exposure was 

suspected. One hybrid poplar 

field was identified 3.5 miles 

from the yard, and this field 

had not been treated in 2002. 

An alfalfa field 2.75 miles 

from the yard was identified 

and it was sprayed with zetacypermethrin 23 days prior to 

the observation in the bee yard. 

Samples of pollen were taken 

and analyzed with no detection 

of zeta-cypermethrin, carbaryl, 

1-naphthol and carbofuran. 

The insecticide coumaphos 

was detected. It is used in 

Check Mite Strips used to 

control Varroa mites.

Note: The insecticide used on 

the alfalfa field was identified 

by the name Mustang and the 

EPA Reg. # 279-3126 was also 

given. Mustang is a pyrethin 

pesticide cancelled in 1983. 

The Reg. # identified the 
-Page 124 of 126-

Table E-1. Cypermethrin and Zeta-Cypermethrin Incident Report Summaries

Incident # Organism(s) 

Affected

Certainty of 

Involvement

Legality of 

Use Description

product Fury and its active 

ingredient is zetacypermethrin.

I014202-

008

Honey Bee (Apis 

millifera)

Unlikely Registered 

Use

A bee keeper reported on Sept 

4, 2002 that there were dead 

bees in his bee yard. It was 

also stated that on Aug. 27, 

2002, the bee keeper removed 

honey and that the hives were 

fine. The inspector opened 

and examined 20 of the twenty 

hives. Colonies appeared to be 

disease free, except for two 

hives with normal chalkbrood. 

Two hybrid poplar fields, 3,25 

and 8 miles from the bee yard, 

were identified. There were no 

insecticide treatments to these 

fields in 2002. An alfalfa field 

had been treated with zetacypermethrin about 50 days 

before symptoms were 

reported. Bee tissue and 

pollen samples were obtained. 

Analyses of the samples did 

not detect any carbaryl, 1-

naphthol or carborfuran. 

Coumaphos was detected in 

both the bee tissue and pollen 

samples. Level were not 

given. Test for Varroa mites 

was negative.
-Page 125 of 126-

Appendix F. Federally Listed Species Potentially at Risk from the Proposed Uses of Alpha Cypermethrin 

Taxon Count by State for Selected Crops

No species exclusions.

Minimum of 1 Acre

All Medium Types Included

alfalfa hay, broccoli, brussels sprouts, cabbage-chinese, cabbage-head, cabbage-mustard, cauliflower, collards, kale, mustard greens, spinach, turnip greens, 

citrus fruit-all, corn-popcorn & sweet corn, corn-sweet for seed, cotton-all, squash-summer, squash-winter, muskmelons and pepinos, celery, escarole and 

endive, lettuce-head, lettuce-leaf, parsley, rhubarb, beans-dry edible excluding limas, beans-dry lima, beans-green lima, beans-snap (green), beans-yard-long, 

peas-green (excluding southern), peas-green southern (cowpeas) - blackeyed, crowder, etc., peas-pigeon, rice-wild, artichokes-excluding jerusalem, carrots, 

chicory, dasheens, ginger root, ginseng, potatoes, radishes, sweet potatoes, turnips, yam (lesser), yams, sorghum for grain, soybeans, sugarbeets for seed, 

sugarbeets for sugar, wheat-all

AL, AZ, AR, CA, CO, CT, DE, DC, FL, GA, ID, IL, IN, IA, KS, KY, LA, ME, MD, MA, MI, MN, MS, MO, MT, NE, NV, NH, NJ, NM, NY, NC, ND, OH, 

OK, OR, PA, RI, SC, SD, TN, TX, UT, VT, VA, WA, WV, WI, WY, an, OA, an, OP

Amphibian, Arachnid, Bird, Bivalve, Conf/cycds, Coral, Crustacean, Dicot, Ferns, Fish, Gastropod, Insect, Lichen, Mammal, Monocot, Reptile

All Crops

Mammal Bird Amphibian Reptil Fish Crustacean Bival Gastropod Arachnid Insect Dico Monocot Ferns Conf/cycd Coral Liche

Alabama 5 4 2 4 15 1 38 12 2 13 4 3

Arizona 8 6 2 2 19 3 16 2

Arkansas 5 4 1 7 2 10 1 1 6 1

California 30 15 6 7 21 8 3 23 161 18 2

Colorado 3 5 6 2 15 1

Connecticut 1 2 1 1 1 2 1

Delaware 1 1 1 1 1

Florida 11 12 2 6 4 1 7 4 47 3 1 2 1

Georgia 5 6 2 2 8 17 2 15 6 2 1 1

Idaho 4 5 4 4 1

Illinois 2 2 2 1 8 1 2 7 2

Indiana 2 1 1 9 2 4 1

Iowa 1 2 3 4 1 3 2

Kansas 2 3 5 1 1 1 1

Kentucky 4 6 6 1 23 1 9

Thursday, May 31, 2012 Page 1 of 22
-Page 126 of 126

-

Louisiana3323321

Maine22212

Maryland21111252

Massachusetts12211312

Michigan32144431

Minnesota1114122

Mississippi54154 1021

Missouri311691171

Montana33421

Nebraska233222

Nevada121 22291

New Hampshire111112

New Jersey1211133

New Mexico5511 1325 13

New York1211311521

North Carolina74258111 2151

North Dakota2321

Ohio11118342

Oklahoma3614312

Oregon34 1512 152

Pennsylvania11162

Rhode Island121111

South Carolina161111 13611

South Dakota143211

Tennessee33 201 4131 15211

Texas6 124911 109 263

Utah33181 242

Vermont2112

Virginia631182 23112 134

Washington846191

West Virginia2116142

Wisconsin225252

Wyoming331732

Thursday, May 31, 2012 Page 2 of 22