2 

 

Problem Formulation for the 

Environmental Fate and Ecological Risk, Endangered 

Species, and Drinking Water Assessments in Support 

of the Registration Review of Acetamiprid 

(E)-N1-[(6-chloro-3-pyridyl)methyl]-N2-cyano-N1-methylacetamidine 

CAS No. 135410-20-7 

PC Code: 099050

Prepared by:

Katrina White, Ph.D., Biologist 

Scott Glaberman, Ph.D., Biologist 

Environmental Risk Branch IV 

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:

Jim Carleton, Ph.D., Senior Scientist 

Thomas Steeger, Ph.D., Senior Science Advisor 

Marietta Echeverria, Branch Chief 

Environmental Risk Branch IV 

September 5, 2012
3 

Table of Contents 

1. Purpose ........................................................................................................................................ 7

2. Description of Regulatory Action ............................................................................................... 7

3. Conclusions from Previous Risk Assessments ........................................................................... 8

3.1. Ecological Risk Assessments .......................................................................................... 8

3.2. Drinking Water Assessments ........................................................................................ 11

4. Mechanism of Action ................................................................................................................ 12

5. Overview of Pesticide Usage .................................................................................................... 13

5.1. Summary of Products and Overview of Usage ............................................................. 13

5.2. Agricultural Uses and Residential Uses on Plants ........................................................ 18

5.3. Use on Trees ................................................................................................................. 21

5.4. Termiticide, Ants Control, and Control of Pests ........................................................... 21

5.5. Usage Data .................................................................................................................... 23

6. Environmental Fate and Transport............................................................................................ 26

6.1. Summary ....................................................................................................................... 26

6.2. Degradation/Transformation of Parent ......................................................................... 31

6.3. Field Dissipation ........................................................................................................... 32

6.4. Degradates/Transformation Products ............................................................................ 34

6.5. Mobility/Sorption .......................................................................................................... 39

6.6. Monitoring Data ............................................................................................................ 40

7. Clean Water Act ........................................................................................................................ 40

8. Receptors................................................................................................................................... 41

8.1. Effects to Aquatic Organisms ....................................................................................... 42

8.1.A. Acetamiprid (Parent) .................................................................................................. 42

8.1.B. Degradate Effects to Aquatic Organisms ................................................................... 45

8.2. Effects to Terrestrial Organisms ................................................................................... 47

8.2.A. Acetamiprid (Parent) Toxicity ................................................................................... 47

8.2.B. Degradate Toxicity to Terrestrial Organisms ............................................................. 51

8.3. Incident Database Review ............................................................................................. 52

9. Identification of Stressors of Concern ...................................................................................... 53

10. Ecosystems Potentially At Risk .............................................................................................. 57

11. Assessment Endpoints ............................................................................................................ 57

12. Conceptual Model ................................................................................................................... 58

12.1. Risk Hypothesis ............................................................................................................ 58

12.2. Conceptual Diagram ..................................................................................................... 59

13. Analysis Plan .......................................................................................................................... 63

13.1. Measures of Exposure ................................................................................................... 64

13.1.A. Exposure in the Aquatic Environment ..................................................................... 64

13.1.B. Exposure to Terrestrial Animals via Residues on Food Items ................................. 65

13.1.C. Exposure to Terrestrial Plants .................................................................................. 66

13.1.D. Exposure to Spray Drift ........................................................................................... 66

13.1.E. Exposure to Terrestrial Plants from Residues in Irrigation Water ........................... 66

13.1.F. Exposure from Applications to Individual Trees ...................................................... 67

13.2. Measures of Effect ........................................................................................................ 67
4 

13.3. Integration of Exposure and Effects ............................................................................. 68

13.3.A. Deterministic and Probabilistic Assessment Methods ............................................. 68

13.3.B. Endocrine Disruptor Screening Program ................................................................. 69

13.3.C. Endangered Species Assessment .............................................................................. 69

13.3.A. Risk Assessment of Pollinators ................................................................................ 70

13.3.B. Human Health Drinking Water Assessment ............................................................ 71

14. Preliminary Identification of Data Gaps ................................................................................. 71

14.1. Fate ................................................................................................................................ 71

14.1.A. Rationales for Requesting Fate Studies ................................................................... 75

14.1.B. Discussion of Additional Fate Data to Reduce Uncertainty or Aid in Monitoring .. 77

14.2. Ecological Effects ......................................................................................................... 78

14.2.A. Testing on Typical End-Use Products (TEP) ........................................................... 86

14.3. Additional Information Needed on Specific Labels, Uses, and Formulation Types .... 86

14.4. Other Information Needs .............................................................................................. 89

15. References ............................................................................................................................... 90

15.1. Literature Cited ............................................................................................................. 90

15.2. Submitted Studies ......................................................................................................... 95

15.2.A. Physical Chemical and Fate Data........................................................................... 109

 

List of Tables

Table 3-1. Existing Uses Assessed in the Completed Ecological Risk Assessments .................. 10

Table 5-1. Summary of Section 3 and Section 24C (Special Local Need) Registrations for 

Acetamiprid (completed 04/12/2012) ......................................................................... 13

Table 5-2. Summary of Use Patterns of Acetamiprid with Well Defined Use Rates for 

Agricultural Crops ...................................................................................................... 18

Table 5-3. Summary of Use Pattern Recommended for Control of Borers, Scale Insects, and 

Hemlock Wooly Adelgids in Ornamental or Non-Bearing Fruit and Nut Trees ........ 21

Table 5-4. Summary of Uses Around Buildings, Paths, Wood, and Equipment ......................... 22

Table 5-5. Screening Level Estimates of Agricultural Uses of Acetamiprid (099050), Sorted 

Alphabetically ............................................................................................................. 23

Table 6-1. Summary of physical-chemical properties of acetamiprid ......................................... 27

Table 6-2. Summary of environmental fate and transport properties of acetamiprid6 ................. 28

Table 6-3. Summary of Terrestrial Field Dissipation Study Results For Acetamiprid ............... 33

Table 6-4. Summary of Maximum Degradate Amounts in Environmental Fate Studies of 

Acetamipridd ............................................................................................................... 37

Table 6-5. Summary of environmental fate and transport properties of the acetamiprid degradate 

IM-1-4 ......................................................................................................................... 38

Table 6-6. Summary of half-lives estimated for residues of parent, IM-1-4, and Unextracted 

residues in metabolism studies.................................................................................... 39

Table 8-1. Categories of Acute Toxicity for Aquatic Animals .................................................... 41

Table 8-2. Categories of Acute Toxicity for Terrestrial Animals ................................................ 42

Table 8-3. Most Sensitive Aquatic Toxicity Endpoints for Acetamiprid .................................... 44

Table 8-4. Aquatic Toxicity Endpoints for Degradates of Acetamiprid ...................................... 46

Table 8-5. Most Sensitive Terrestrial Animal Toxicity Endpoints for Acetamiprid ................... 49
5 

Table 8-6. Most Sensitive Terrestrial Plant Toxicity Endpoints for Acetamiprid. ...................... 51

Table 8-7. Available Terrestrial Animal Toxicity Endpoints for Degradates. ............................ 51

Table 9-1. Comparison of Available Empirical Toxicity Data for Acetamiprid and Degradates 54

Table 9-2. ECOSAR Quantitative Structure-Activity Relationship (QSAR) Toxicity Predictions 

for Acetamiprid and Degradates ................................................................................. 55

Table 9-3. Summary of Residues of Concern and Methods of Estimating Exposure for Different 

Classes of Organisms .................................................................................................. 56

Table 14-1. Summary of Submitted Environmental Fate Studies, Study Classifications and Data 

Gaps for Acetamiprid and Its Degradates ................................................................... 72

Table 14-2. Summary of Submitted Aquatic and Terrestrial Effects Studies and Data Gaps for 

Parent Acetamiprid. .................................................................................................... 80

Table 14-3. Summary of Submitted Aquatic and Terrestrial Animal Effects Studies and Data 

Gaps for Degradates of Acetamiprid. ......................................................................... 84

List of Figures 

Figure 5-1. Average Pounds Acetamiprid Used by Crop Reporting District (2006-2010). ........ 25

Figure 6-1. Potential Degradation Pathway for Acetamiprid. Bold degradates had greater than 

10% applied radioactivity associated with the compound in at least one submitted 

fate study. .................................................................................................................. 35

Figure 6-2. Structure of Pyridylmethylamine Nicotinoid Insecticides and Nicotine.................... 36

Figure 12-1. Conceptual model depicting stressors, exposure pathways, and potential effects to 

aquatic organisms and their habitat from the use of acetamiprid .............................. 60

Figure 12-2. Conceptual model depicting stressors, generic exposure pathways, and potential 

effects to terrestrial organisms (terrestrial plants, terrestrial invertebrates, and dietary 

routes of exposure for terrestrial vertebrates) and their habitat from the use of 

acetamiprid ................................................................................................................ 61

Figure 12-3. Conceptual model depicting stressors, drinking water and inhalation exposure 

pathways, and potential effects to terrestrial animals from the use of acetamiprid .. 62

Figure 12-4. Conceptual model depicting stressors, exposure pathways, and potential effects to 

aquatic and terrestrial organisms from applications of acetamiprid to individual trees.

 ................................................................................................................................... 63

List of Appendices

Appendix A. Supplemental Environmental Fate Information .................................................. 116

Appendix B. Summary of Available Effects Studies ................................................................. 124

Appendix C. Example ECOSAR Output ................................................................................... 138

Appendix D. Reference List for OPPTS 835 Guidelines .......................................................... 140

Appendix E. Results from Screening Imbibition Program (SIP) and the Screening Tool for 

Inhalation Risk Assessment (STIR) ..................................................................... 142

Appendix F. Agency risk quotient (RQ) metrics and levels of concern (LOC) for Federallylisted (listed) threatened/endangered and non-listed species per risk class .......... 145

Appendix G. Data Call-In Justification Tables for Non-Guideline Ecological Effects Studies 146

Appendix H. Preliminary Estimate of Surface Water Concentrations for Ecological Risk 
6 

Assessment ........................................................................................................... 148

 
7 

1. Purpose 

The purpose of this problem formulation is to provide an understanding of the environmental fate 

and ecological effects of the registered uses of acetamiprid ((E)-N1-[(6-chloro-3-

pyridyl)methyl]-N2-cyano-N1-methylacetamidine). Acetamiprid is a neonicotinoid insecticide 

registered for the following agricultural crops: alfalfa, apple, beans, blueberry, bushberry, 

caneberry, bulb vegetables, cole crops, cucurbit vegetables, fruiting vegetables, leafy vegetables, 

citrus, clover, cotton (unspecified), crabapple, cranberry, deciduous fruit trees (unspecified), 

grapes, leafy vegetables, legume vegetables, onion, ornamental herbaceous plants, ornamental 

nonflowering plants, ornamental wood shrubs and vines, pear, pine seedlings, pome fruits, Irish 

white potato, root and tuber vegetables, small fruits, soybeans, strawberry, tobacco, tomato, and 

tree nuts. Acetamiprid is registered for the following residential/commercial use areas/sites: 

ornamental and flowering plants, ornamental shrubs, ornamental trees, houseplants, gardens, 

poplar trees, preconstruction sites, households, outdoor building perimeters, residential areas, 

greenhouses, shadehouses, and lathouses. It is also registered to control ants, cockroaches, 

termites, and various other insects indoors and outdoors. This document will provide a plan for 

analyzing data relevant to acetamiprid and for conducting environmental fate and ecological risk, 

endangered species, and drinking water assessments for its registered uses. Additionally, this 

problem formulation is intended to identify data gaps, uncertainties, and potential assumptions 

used to address those uncertainties relative to characterizing the ecological risk associated with 

the registered uses of acetamiprid. 

2. Description of Regulatory Action 

The Food Quality Protection Act (FQPA) of 1996 mandated the Environmental Protection 

Agency (EPA) implement a new program for assessing the risks of pesticides, i.e., Registration 

Review1

. All pesticides distributed or sold in the United States (U.S.) generally must be 

registered by EPA. The decision to register a pesticide is based on the consideration of scientific 

data and other factors showing that it will not cause unreasonable risks to human health, workers, 

or the environment when used as directed on product labeling. The Registration Review program 

is intended to ensure that, as the ability to assess risk evolves and as policies and practices 

change, all registered pesticides continue to meet the statutory standard of no unreasonable 

adverse effects to human health and the environment. Changes in science, public policy, and 

pesticide use practices will occur over time; through the new Registration Review program, the 

Agency periodically reevaluates pesticides to ensure that as change occurs, products in the 

marketplace can be used safely. 

As part of the implementation of the Registration Review program pursuant to Section 3(g) of 

the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA), the Agency is beginning its 

evaluation to determine whether acetamiprid continues to meet the FIFRA standard for 

registration. This problem formulation for the environmental fate and ecological risk assessment 

chapter in support of the Registration Review is intended for the initial docket opening the public 

phase of the review process. 

 

1

 http://www.epa.gov/oppsrrd1/registration_review 
8 

3. Conclusions from Previous Risk Assessments 

3.1. Ecological Risk Assessments 

Acetamiprid is used in outdoor sites and thus has the potential to result in exposures to wildlife. 

The Agency conducted a new chemical ecological risk assessment and drinking water 

assessment on acetamiprid in 2002. New use requests prompted five additional assessments 

completed in 2004, 2005, 2007, 2009, and 2011. These assessments serve as a basis for this 

problem formulation. The assessments are briefly discussed below. 

A Section 3 new chemical ecological risk assessment was conducted for acetamiprid use on 

flowers and ornamentals, leafy vegetables, cole crops, cotton, fruiting vegetables, citrus, pome 

fruits, grapes and seeds (USEPA, 2002, D270368). The highest proposed maximum seasonal 

application rate for any crop was 0.6 pounds active ingredient per acre (lbs ai/A) for pome fruits. 

Acetamiprid was characterized as posing low risk to the environment relative to most other 

insecticides based on its selective toxicity, low use rates, and relatively rapid rate of degradation. 

Direct acute risk to aquatic invertebrates with direct application into shallow water bodies was 

predicted, and chronic risks to some species of aquatic invertebrates (due to the selectivity of 

acetamiprid) were predicted for other uses. Direct risk to Federally-listed threatened or 

endangered species (hereafter referred to as “listed species”) of terrestrial wildlife, terrestrial 

plants, and saltwater invertebrates were also predicted. Direct effects on terrestrial invertebrates 

were presumed based on acetamiprid being an insecticide; however, actual risk to terrestrial 

invertebrates was not quantified. The only residue of concern evaluated was the parent 

acetamiprid. 

Subsequent new use assessments were conducted for tobacco, potatoes, and residential uses in 

2004 (USEPA, 2004, D304025) and for cucurbits, stone fruits, and tree nuts in 2005 (USEPA, 

2005, D319610). The 2004 assessment indicated that acetamiprid may pose direct acute risks to 

non-listed and listed freshwater invertebrates, listed mammals, and listed terrestrial plants while 

the 2005 assessment indicated additional chronic risks to non-listed and listed aquatic 

invertebrates and non-listed and listed mammals and both acute and chronic risks to non-listed 

and listed birds. Additionally, direct risk to listed terrestrial plants was indicated. The maximum 

seasonal application rate for tree nuts (0.72 lbs ai/A) assessed in 2005 was higher than the 

highest rate previously evaluated. The risk assessments also noted that acetamiprid was 

moderately toxic to bees and belonged to a class of chemicals that has been associated with 

causing behavioral effects in bees. Potential for indirect effects to fish was also identified. The 

only residue of concern evaluated in the risk assessment was parent acetamiprid. 

A 2007 assessment (USEPA, 2002, D270368) for new uses on berries, bulb vegetables, 

succulent legumes, and strawberries concluded that the proposed application rates were lower 

than those previously assessed, resulting in lower risk quotients (RQs); however, RQ values still 

exceeded the Agency’s levels of concern (LOCs) for the same previously identified taxa. The 

only residue of concern evaluated in the risk assessment was the parent acetamiprid. 

 

A 2009 new use assessment (Morrica et al., 2005) for new uses on red clover and the climbing 
9 

vine small fruit subgroup (crop subgroup 13-07F, except fuzzy kiwifruit) indicated that the 

proposed uses could result in direct effects to birds (and to reptiles and terrestrial-phase 

amphibians for which birds serve as surrogates) on both an acute and chronic exposure basis 

(USEPA, 2009, D364328). Listed freshwater and estuarine/marine aquatic invertebrates and 

mammals may be affected by acute exposures to acetamiprid, and freshwater and 

estuarine/marine aquatic invertebrates may be directly affected by chronic exposures. Finally, 

the assessment also indicated that listed dicotyledonous plants could be adversely affected by 

spray drift from aerial applications to grapes and climbing vine small fruits. Indirect effects were 

predicted for aquatic plants, fish (and aquatic-phase amphibians for which fish serve as 

surrogates), estuarine/marine fish and aquatic invertebrates. The assessment considered the 

parent and the degradate, IM 1-4, as residues of concern and risk was evaluated using a total 

toxic residue approach.2

 Overall, the inclusion of IM-1-4 did not affect the risk conclusions. 

In 2011, an assessment was completed for both existing and newly proposed agricultural uses of 

acetamiprid (described in Table 3-1); the uses that have been approved are included in this 

document, while uses that are still pending are not discussed. The existing uses were re-evaluated 

for aquatic organisms because the degradate IM 1-4 and unextracted residues were assumed to 

also be residues of concern; therefore, a total toxic residues approach was used to assess risk of 

both existing and proposed uses. IM-1-4 was considered as a residue of concern in this 

assessment because it has a considerably longer half-life than the parent compound and available 

data suggest it is as toxic as the parent compound to aquatic animal species. The screening-level 

risk assessment concluded that all proposed uses of acetamiprid have the potential for direct 

acute effects to listed aquatic invertebrates. There was also the potential for direct acute effects to 

non-listed aquatic invertebrates for five of the seven crop uses (including fruiting vegetables, 

citrus, and pome fruit). The Agency’s chronic LOC for aquatic invertebrates was also exceeded 

for all proposed crop uses of acetamiprid. 

The assessment in 2011 also indicated that for terrestrial organisms, there was a potential for 

direct acute effects to both listed and non-listed birds (reptiles and terrestrial-phase amphibians) 

for all of the proposed crop uses of acetamiprid. The higher risk estimates for birds compared to 

previous assessments were based on a recently study in zebra finches (Taeniopygia guttata) 

where acetamiprid was shown to be very highly toxic to passerine birds on an acute exposure 

basis. The assessment also indicated that acetamiprid had the potential to cause direct acute 

effects to listed mammals and terrestrial plants for all uses evaluated except for soybeans. In 

addition, there was also potential for direct effects to non-listed terrestrial plants for assessed 

uses on citrus and pome fruit. 

Although the 2011 assessment did not predict direct risk to fish and aquatic plants for any 

assessed uses, the assessment noted that indirect effects to all taxa except aquatic non-vascular 

plants could occur due to effects on prey or habitat.3

 

2

 The residues of concern for ecological risk assessment are defined by the Environmental Fate and Effects Division. 

The residues of concern for human health drinking water are the parent only and these are determined by the Health 

Effects Division. 

3

 Indirect effects to terrestrial and aquatic vascular plants may occur due to effects on birds and mammals that are 
10 

Table 3-1. Existing Uses Assessed in the Completed Ecological Risk Assessments 

Use Site/ Source Year 

Assessed 

Single App. 

Rate 

(lbs. ai/A) 

Number of 

Apps. 

Seasonal 

App. Rate 

(lbs. ai/A) 

Interval 

Between 

Apps. 

(days) 

Comments 

Ready to Use Hand spray on 

Ornamentals, Citrus, 

Vegetables, and Fruits 

2002 NS NS NS 7 -- 

Residential Uses 2004 2.2 NS NS NS -- 

Ornamental and Flowering 

Plants 2002 0.15 lbs ai NS 0.55 lbs ai 7 -- 

Cotton 2002, 

2011 0.1 4 0.4 7 --

Leafy Vegetables within Crop 

Group 4 

2002, 

2011 0.075 5 0.375 7 --

Head and Stem Cole Crops 2002, 

2011 0.075 5 0.375 7 --

Fruiting Vegetables (within 

Crop Group 8-10) 

2002, 

2011 0.075 4 0.3 7 --

Canola 2002 

0.03 

(5.0 g ai/kg 

seed; 6 lbs 

treated 

seed/A) 

1 NA NA -- 

Citrus (within Crop Group 

10-10) 

2002, 

2011 

0.25 5 0.55 7 --

0.25 

(assumed2

)

2 

(assumed2) 7 --

0.11 

(assumed2) 5 0.55 7 --

Pome Fruit (within Crop 

Group 11-10) 

2002, 

2011 0.15 4 0.60 12 --

Tuberous and Corm 

Vegetables (within Crop Subgroup 1C) 

2004, 

2011 0.075 4 0.3 7 --

Tobacco2 2004, 

2011 0.075 4 0.3 7 None

Grapes and Other Climbing 

Small Fruits (except Fuzzy 

Kiwifruit, within Crop Subgroup 13-07F) 

2002, 

2009, 

2011 

0.1 2 0.2 14 None

Stone Fruit (within crop 

Group 12) 

2005, 

2011 0.15 4 0.6 10 None

Cucurbits (within Crop Group 

9) 

2005, 

2011 0.10 5 0.5 5

Multiple 

seasons per 

year

Tree Nuts (within Crop Group 

14, including Pistachio) 

2005, 

2011 0.18 4 0.72 7 in 2005 14 in 2011 --

Edible Podded Legume 

(within Crop Subgroup-6A) 

2007, 

2011 0.1 3 0.3 7 --

 pollinators or important in seed dispersal of the species. 
11 

Use Site/ Source Year 

Assessed 

Single App. 

Rate 

(lbs. ai/A) 

Number of 

Apps. 

Seasonal 

App. Rate 

(lbs. ai/A) 

Interval 

Between 

Apps. 

(days) 

Comments 

and Succulent Shelled Peas 

and Beans (within Crop SubGroup 6B) 

Strawberries and Other Low 

Growing Berries (within Crop 

Sub-group 13-07G) 

2007, 

2011 0.13 2 0.26 7 --

Blueberries and Other Bush 

Berries (within Crop SubGroup 13-07B) and Cane 

Berries (within Crop Subgroup 13-07A) 

2007, 

2011 0.085 5 0.5 7 --

Onions and Other Bulb 

Vegetables (within Crop 

Group 3-07) 

2007, 

2011 0.15 4 0.6 7 --

Clover (for use in OD, OR, 

and WA only) 

2009, 

2011 0.075 1 0.075 NA --

Mustard 2002 

0.03 

(5.0 g ai/kg 

seed; 6 lbs 

treated 

seed/A) 

1 NA NA -- 

Soybean 2011 0.04 2

0.078

(0.08 

assumed1

)

7

150 foot 

buffer

25 foot buffer

Abbreviations: App=Application 

1 Assumed for Tier I aquatic exposure modeling and terrestrial exposure modeling because it is not possible to model 

multiple applications at different rates. 

2

Scenarios were assumed for modeling purposes because the five applications of the single maximum application 

rate cannot be made according to the maximum seasonal application rate.

3.2. Drinking Water Assessments 

The outdoor uses of acetamiprid potentially contribute residues to drinking water. The most 

recent Tier I drinking water assessment to support a human health risk assessment was 

completed in 2011 (USEPA, 2011, D394234, D394479). The assessment analyzed the drinking 

water concentrations for a number of proposed and existing agricultural uses assessed in the 

2011 Ecological Risk Assessment (see Table 3-1). The Metabolism Assessment Review 

Committee (MARC) reported that the residue of concern for acetamiprid is the parent only 

(USEPA, 2001). Unextracted residues were observed in aerobic soil and aerobic aquatic 

metabolism studies and in some studies it was uncertain whether some of the unextracted 

residues contained parent compound (MRIDs 46255603, 44651881, 44699101, 44651879, 

44988513, and 44988512).4

 Additionally, the extraction techniques were not exhaustive and it is 

 

4

 If unextracted residues formed along with loss of the parent compound it is possible that some of the unextracted 

residues are the parent compound; however, if the parent degraded significantly in the beginning of the study and 
12 

likely that if different extraction techniques were used, a higher percentage would be extracted. 

Therefore, when it was uncertain, half-lives used in surface water and ground water modeling 

were estimated assuming that the unextracted residues were the parent compound. Then these 

new half-life values based on residues of parent and unextracted residues were used in modeling 

to estimate drinking water concentrations.5 When the parent was shown to degrade at the 

beginning of the study and unextracted residues did not appear until the end of the study, it was 

assumed that the unextracted residues were not the parent compound.6

 Estimated drinking water 

concentrations (EDWCs) in surface water were derived using FQPA Index Reservoir Screening 

Tool (FIRST version 1.1.1, March 25, 2008) and ground water concentrations were estimated 

using the Screening Concentration in Ground Water (SCI-GROW version 2.3, July 29, 2003). 

For existing uses, the highest acute EDWC (estimated for acetamiprid use on tree nuts) was 42.8 

μg acetamiprid+unextracted residues/L water and the annual average concentration was 12.2 μg 

acetamiprid+unextracted residues/L water. The highest estimated ground water concentration 

for existing uses was 0.013 μg/L. Whether EDWC will result in a human health risk concern is 

determined by considering EDWC as a part of aggregate dietary exposure (food and water) and 

comparing dietary exposure estimates to mammalian toxicity endpoints (modified by the 

necessary uncertainty and/or safety factors) to determine whether the LOC is exceeded for the 

dietary exposure pathway. Because of the absence of data on acetamiprid, the potential effects 

of drinking water treatment (e.g., chlorination, ozonation) were not considered in the assessment. 

4. Mechanism of Action 

Acetamiprid is a chloronicotinyl insecticide belonging to the cyano-substituted sub-class of the 

neonicotinoid pesticides, which also includes thiacloprid (CAS No. 111988-49-9). Similar to 

other neonicotinoids including nitroguanidine-substituted compounds such as imidacloprid, 

clothianidin, dinotefuran and thiamethoxam, acetamiprid is a systemic, broad-spectrum 

insecticide that acts as a stomach poison against sucking and some biting insects (Sur and Stork, 

2003). The compound acts as an agonist of the nicotinic acetylcholine receptor (nAChR) at the 

postsynaptic membrane of nerve cells. The active ingredient interrupts the function of the insect 

nervous system. As reported in the original Section 3 risk assessment, biochemical radio-ligand 

binding studies show that acetamiprid interacts with high affinity at the nAChR binding site in 

insects, and with low affinity at the nAChR in vertebrates (USEPA, 2002, D270368). The 

cyano-substituted neonicotinoids exhibit a lower toxicity to honeybees (LD50 values of <12.5 to 

14.6 μg/bee) than the nitro-substituted neonicotinoids (18 to 138 ng/bee) (Iwasa et al., 2004). 

Inhibition of cytochrome P450 activity in honeybees (Apis mellifera) resulted in increased 

toxicity of acetamiprid, indicating that P450 metabolism is an important detoxifying pathway for 

insects (Iwasa et al., 2004). 

 unextracted residues did not form until the end of the study, the unextracted residues are unlikely to be the parent 

compound. 

5

 Half-lives including unextracted residues were calculated and used in modeling for the aerobic soil metabolism 

studies (MRID 46255603, 44651881 for clay loam soil, MRID 44651879) and aerobic aquatic metabolism studies 

(MRID 44988513), and anaerobic aquatic metabolism studies (MRID 44988512). 

6

 This occurred in two soils (sandy loam and silty clay loam) in an aerobic soil metabolism study (MRID 44651881). 
13 

5. Overview of Pesticide Usage 

5.1. Summary of Products and Overview of Usage 

Acetamiprid was first registered in 2002 (USEPA, 2012). It is an insecticide used to control a 

variety of insects including aphids, beetles, caterpillars, leafhoppers, stinkbugs, thrips, whiteflies, 

boll worms, fleahoppers, earwigs, silverfish, termites, ants, cockroaches, weevils, Colorado 

potato beetles, potato psyllids, wireworms, household pests, bedbugs, Lygus bug, 

carpenterworm, apple maggots, borers (excluding the Emerald ash borer) and scale insects. 

There are currently 37 Section 3 registrations containing acetamiprid and 14 Section 24C 

(Special Local Needs) registrations (Table 5-1). Some formulated end products of acetamiprid 

contain other active ingredients in addition to acetamiprid; a flowable concentrate (Reg. No. 

8033-116) and two termiticides (Reg. No. 8033-96 and 8033-1097) also contains the synthetic 

pyrethroid insecticide bifenthrin (CAS No. 82657-04-3) and one homeowner product (Reg. No. 

8033-108) contains the conazole fungicide triticonazole (CAS No. 131983-72-7). Use sites 

include agriculture, residential, commercial, industrial, and nursery use sites. All use sites are 

described in more detail in the following sections. 

Formulations include water dispersible granules (WDG), emulsifiable concentrates (EC), soluble 

concentrates (SC), liquids, water soluble packets (WSP), impregnated stickers, impregnated bait 

stations, gels, and an attract-and-kill device. Water dispersible granules, EC, SC, and WSP are 

applied as ground or aerial sprays and may result in spray drift. Gels are used as spot treatments, 

beads, and thin films to control ants and cockroaches. Water dispersible granules are all applied 

as a liquid. There are also seed treatment uses on potatoes, canola, and mustard. Some liquid 

formulations are injected into trees. Termiticides may be applied as a liquid or foam. They may 

be applied on soil surfaces as a perimeter treatment, crack and crevice treatment, or brush and 

spray. The may also be applied into soil using trenching, rodding, sub slab injection, and soil 

excavation techniques. Some termiticide products are applied to subsurfaces into piping, 

injections, and reticulation delivery systems. The impregnated materials are generally stickers 

used to control flies. The attract-and-kill device is a pheromone mixed with acetamiprid that is 

hung in trees. 

Table 5-1. Summary of Section 3 and Section 24C (Special Local Need) Registrations for 

Acetamiprid (completed 04/12/2012) 

Reg. 

Number

Registration 

Name

Percent 

Acet. Form. General Summary of Use Sites Target pests 

Agricultural Use Patterns That Are not Seed Treatments

8033-20 Acetamiprid 

Technical 99.5 

8033-22 Tristar 70WSP 

Insecticide 70 WSP Ornamentalsj Many: aphids, beetles, caterpillars, thrips, etc. 

8033-23 Assail 70WP 

Insecticide 70 WP 

Many: cotton, fruits, 

vegetables, tobacco, tree 

nuts, clover, etc.

Many: aphids, whitefly, 

weevils, thrips, etc.

 

7

 These are the parent labels for SLN registration numbers OK110002 and OK100003. 
14 

Reg. 

Number

Registration 

Name

Percent 

Acet. Form. General Summary of Use Sites Target pests 

8033-24 Intruder Brand 

Insecticide 70 WP Cotton Aphids, whitefly, plant bugs, fleahopper, boll worm 

8033-36c Assail 30 SG 

Insecticide 30 WDG 

Many: cotton, fruits, 

vegetables, tobacco, tree 

nuts, clover, etc.

Many: aphids, whitefly, 

weevils, thrips, etc.

8033-26a Acetamiprid 70 

WSP Insecticide 70 WSP Outdoor use only Ants, termites 

8033-94 Tristar 30 SG 

Insecticide 30 SC Ornamentals and vegetables Many: aphids, whitefly, 

thrips, etc.

8033-101f Acetamiprid SL 

Insecticide 8.5 SC Cotton Aphids, whiteflies 

8033-106 TRISTAR 8.5 SL 

INSECTICIDE 8.5 SC 

Ornamentals, transplants of 

leafy & fruiting vegetables, 

greenhouse tomatoes 

Broad range, including 

aphids, whiteflies, scales, 

caterpillars, weevils, 

leafminers 

8033-116h Justice OF 

Insecticide 

13 

10e FC Soybean 

Many, including aphids, 

beetles, earworm, rootworm, 

grasshoppers 

ID070011 Assail 70 WP 

Insecticide 70 WP Alfalfa Lygus bug 

ID090014 Assail 30 SG 

Insecticide 30 WDG Alfalfa seed crop Lygus bug 

NV070004 Assail 70 WP 

Insecticide 70 WP Alfalfa seed crop Lygus bug 

OR070017 Assail 70 WP 

Insecticide 70 A&K Alfalfa seed crop Lygus bug 

OR090005 Assail 70 WP 

Insecticide 70 WP Poplar (hybrid) Carpenterworm 

UT090001 Assail 70 WP 

Insecticide 70 WP Alfalfa seed crop Lygus bug 

WA060009 Tristar 30 SG 

insecticide 30 SC 

Fruit and nut trees (nonbearing), apples, crabapples, 

pears, ornamental plants and 

trees 

Apple maggot 

WA060011 Tristar 70 WSP 

Insecticide 70 WSP 

Crabapples, pears, fruit trees, 

crops, ornamental plants, 

ornamental trees, residential 

areas, nonag areas (public 

health) (outdoor) 

Apple maggot 

WA070006 Assail 70 WP 

Insecticide 70 WP Alfalfa seed crop Lygus bug 

WA110010 Tristar 8.5 SL 

Insecticide 8.5 SC 

Apples, crabapples, pears, 

ornamental plants and trees, 

non-bearing fruit and nut 

trees in non-agricultural 

quarantine and pest-free areas 

(including residential areas) 

Apple maggot 

WY080010 Assail 70 WP 

Insecticide 70 WP Alfalfa seed crop Lygus bug 

Seed Treatments 
15 

Reg. 

Number

Registration 

Name

Percent 

Acet. Form. General Summary of Use Sites Target pests 

8033-95d

Acetamiprid 50 

FS 

Insecticide Seed 

Treatment 

40 RTU 

liquid 

Canola and mustard seed, 

potato seed piece 

Aphids, Colorado potato 

beetle, flea beetle, leaf 

hopper, potato psyllid, 

wireworm 

Ready To Use Products/Homeowner Use That are not Ant Baits or Impregnated Materials

8033-21 Acetamiprid RTU 

Insecticide .006 RTU spray 

Ornamentals, vegetables, 

citrus, pome fruits 

Many: aphids, beetles, 

caterpillars, leafhoppers, 

stinkbugs, etc. 

8033-25 

Acetamiprid 70 

WSP Insecticide 

For Homeowner 

Use 

70 WSP Outdoor building perimeters Ants, earwigs, silverfish, 

termites etc. 

8033-107g

Acetamiprid 

Concentrate 

Insecticide 

0.5 Ornamentals, vegetables, 

fruits, houseplants 

Many: aphids, whitefly, 

thrips, etc. 

8033-108 

Acetamiprid + 

Triticonazole 

Concentrate 

0.26 

0.78i

Ornamentals, roses, flowers, 

trees, shrubs, houseplants 

Many: aphids, whitefly, 

thrips, etc. 

8033-107g

Acetamiprid 

Concentrate 

Insecticide 

0.5 Ornamentals, vegetables, 

fruits, houseplants 

Many: aphids, whitefly, 

thrips, etc. 

Ant and Cockroach Baits and Gels 

8033-28 

Acetamiprid 

(F5025) 0.15% 

Sweet Bait GelAnts OTC 

0.15 Gel Indoor/outdoor Sweet and grease eating ants 

8033-29b

Acetamiprid 

(F5025) 0.15% 

Sweet Bait Gel 

Ants PMP 

0.15 Gel Indoor/outdoor Ants 

8033-30 

Acetamiprid 

(F5025) 0.15% 

Sweet Bait Gel 

Cockroach OTC 

0.15 Gel Indoor/outdoor Cockroaches 

8033-31 

Acetamiprid 

(F5025) 0.15% 

Sweet Bait Gel 

Cockroaches 

0.15 Gel Indoor/outdoor Cockroaches 

8033-32 

Acetamiprid 

(F5025) Bait 

Station 

CockroachesOTC 

0.35 

IM-BS in 

childresistant 

container 

Indoor/outdoor Cockroaches 

8033-33 

Acetamiprid 

(F5025) Bait 

Station 

CockroachesPMP 

0.35 Indoor/outdoor Cockroaches 

8033-34 Acetamiprid 

(F5025) 0.35% 0.35 Gel Indoor/outdoor Cockroaches 
16 

Reg. 

Number

Registration 

Name

Percent 

Acet. Form. General Summary of Use Sites Target pests 

Protein Bait Gel 

Cockroach OTC 

8033-35 

Acetamiprid 

(F5025) 0.35% 

Protein Bait Gel 

PMP Cockroaches 

PMP 

0.35 Gel Indoor/outdoor Cockroaches 

8033-90 

Acetamiprid 

(F5025) 0.35% 

Cockroach Bait 

Gel-OTC 

0.35 Gel Indoor/outdoor Cockroaches 

8033-91 

Acetamiprid 

(F5025) 0.35% 

Cockroach Bait 

Gel-PM 

0.35 Gel Indoor/outdoor Cockroaches 

8033-92 

Acetamiprid 

(F5025) 0.35% 

Cockroach Bait 

Station OTC 

0.35 IM- BS Indoor/outdoor Cockroaches 

8033-93 

Acetamiprid 

(F5025) 0.35% 

Cockroach Bait 

Station PMP 

0.35 IM- BS Indoor/outdoor Cockroaches 

8033-97 

Acetamiprid 

(F5025) 0.075% 

Sweet Bait Gel - 

Ants OTC 

0.075 Gel Indoor/outdoor Ants 

8033-98 

Acetamiprid 

(F5025) 0.075% 

Sweet Bait GelAnts-PMP 

0.075 Gel Indoor/outdoor Ants 

8033-99 

Acetamiprid 

(F5025) 0.075% 

Gel Bait Station 

Ants - OTC 

0.075 IM- BS Indoor/outdoor Ants 

8033-100 

Acetamiprid 

(F5025) 0.075% 

Gel Bait Station 

Ants - PMP 

0.075 IM- BS Indoor/outdoor Ants 

8033-105 

Acetamiprid 

0.075% Protein 

Ant Bait Station 

OTC 

0.075 IM- BS Indoor/outdoor Ants 

Termiticides 

8033-96 

F4688 50 WSP 

Insecticide 

Termiticide 

22.73 

27.27e WSP 

Indoor/outdoor, food/feed 

handling establishments; 

mattresses 

Termites, household pests 

(ants, bees, wasps, biting 

flies, centipedes, chiggers, 

cockroaches, crickets, 

earwigs, fleas, ticks, flies, 

mosquitoes, spiders, 
17 

Reg. 

Number

Registration 

Name

Percent 

Acet. Form. General Summary of Use Sites Target pests 

scorpions, silverfish, 

sowbugs, stink bugs, etc.) , 

bedbugs 

8033-109 

F5688 11% ME 

Insecticide 

Termiticide 

5 

6e EC Indoor/outdoor, food/feed 

handling establishments 

Termites, household pests 

(ants, bees, wasps, biting 

flies, centipedes, chiggers, 

cockroaches, crickets, 

earwigs, fleas, ticks, flies, 

mosquitoes, spiders, 

scorpions, silverfish, 

sowbugs, stink bugs, etc.), 

bedbugs 

OK100001 F4688 50 WSP 

Insecticide 

Termiticide 

22.73 

27.27e WSP Outdoors Termites 

OK110002 F5688 11% ME 

Insecticide 

Termiticide 

5 

6e EC 

New or post-construction 

sub-concrete slab treatments 

through piping or similar 

delivery systems 

Termites 

OK100003 

Transport 

Termiticide 

Insecticide 

22.73 

27.27e WSP Outdoors Termites 

Impregnated Materials 

8033-114 

F7180-8 Fly 

Sticker 

Insecticide - PMP 

4.4 IMsticker Indoor/outdoor House flies, little house flies, 

blow flies, bottle flies, flesh 

flies, phorid flies, fungus 

gnats, and vinegar (fruit) 

flies. 8033-115 

F7180-8 Fly 

Sticker 

Insecticide OTC 

4.4 IMsticker Indoor/outdoor 

WP=wettable powder; SC=soluble concentrate; WSP=water soluble packet; RTU-ready to use; EC=emulsifiable 

concentrate; WDG=water dispersible granules; IM=impregnated material; FC=flowable concentrate; BS=bait 

station; Acet.=acetamiprid; reg=registration; OTC=over the counter; PMP=pest management professionals; 

A&K=attract-and-kill device 

a

 Only for Sale to, and for Use and Storage by Pest Management Professionals 

b

 Inject into cracks & crevices w/syringe or bait injector c

 Geographical restrictions for certain use sites; chemigation permitted for cranberries & potatoes only 

d Must not subsequently apply to potato plants grown from treated seed pieces; for canola & mustard, use only in 

commercial seed treatment facilities; all treated seed must be dyed; do not treat seed for fall planting 

e

 Percent bifenthrin 

f Chemigation prohibited 

g For residential use sites only; not for commercial production 

h

 Buffer is required with use 

i

 Percent triticonazole 

j Not for woodlands or forest management, not for homeowner use 
18 

5.2. Agricultural Uses and Residential Uses on Plants 

BEAD prepares a Label Use Information System (LUIS) Report summarizing all registered uses 

of a product. The EFED Table 1 report was used as the source to summarize all relevant uses of 

acetamiprid. The report was completed on April 16, 2012. Table 5-2 summarizes all 

agricultural uses with maximum single application rates provided in lbs ai/A. These uses include 

aerial or ground broadcast applications of liquids to alfalfa, apple, beans, blueberry, bushberry, 

caneberry, bulb vegetables, cole crops, cucurbit vegetables, fruiting vegetables, leafy vegetables, 

citrus, clover, cotton (unspecified), crabapple, cranberry, deciduous fruit trees (unspecified), 

grapes, leafy vegetables, legume vegetables, onion, ornamental herbaceous plants, ornamental 

nonflowering plants, ornamental wood shrubs and vines, pear, pine seedlings, pome fruits, Irish 

white potato, root and tuber vegetables, small fruits, soybeans, strawberry, tobacco, tomato, and 

tree nuts. Seed treatments are also allowed on potatoes, canola/rape, and mustard. The 

maximum number of applications per year was not specified on the labels. 

Table 5-2. Summary of Use Patterns of Acetamiprid with Well Defined Use Rates for 

Agricultural Crops 

Use Site 

Application 

Method, 

Timing 

Form 

Max Single 

App. Rate 

(lbs ai/A) 

Max # 

Apps / 

CC 

Max App 

Rate/CC 

(lbs ai/A) 

Max App 

Rate/Year 

(lbs ai/A) 

Minimum 

Treatment 

Interval 

(days) 

ALFALFA1 Broadcast, 

Foliar WP 0.0744 NS NS NS NS 

ALFALFA2 Broadcast, 

Foliar WP 0.074-0.075 3, 44 0.225-.2975 NS 7, 14 

APPLE Broadcast, 

Foliar SC 0.15 NS NS NS 12 

BEANS Broadcast, 

Foliar WDG 0.0994-0.1006 3 0.3-0.3019 NS 7 

BLUEBERRY Broadcast, 

Foliar L-RTU 0.0005 5 NS NS 7 

BLUEBERRY, 

BUSHBERRY, 

CANEBERRY 

Broadcast, 

Foliar 

WDG, 

WP 0.0994-0.1006 NS, 5 0.4988-0.5006 NS 7 

BULB 

VEGETABLES 

Broadcast, 

Foliar WP 0.1488-0.15 4 0.5994-0.6 NS 7 

BULB 

VEGETABLES, 

COLE CROPS, 

CUCURBIT 

VEGETABLES, 

FRUITING 

VEGETABLES, 

LEAFY 

VEGETABLES 

Broadcast, 

Pretransplant, 

Foliar 

L 0.1529 NS 0.1529 NS NS 

CANOLA\RAPE Seed 

Treatment L-RTU 0.5039 lbs 

ai/lbs seed NS NS NS NS 
19 

Use Site 

Application 

Method, 

Timing 

Form 

Max Single 

App. Rate 

(lbs ai/A) 

Max # 

Apps / 

CC 

Max App 

Rate/CC 

(lbs ai/A) 

Max App 

Rate/Year 

(lbs ai/A) 

Minimum 

Treatment 

Interval 

(days) 

CITRUS 

Broadcast, 

Foliar, Petal 

Fall 

WDG, 

WP 0.2494 NS 0.5494 NS 7 

CLOVER Broadcast, 

Foliar 

WP, 

WDG 0.0744-0.075 1 0.0744 NS NS 

COLE CROPS Broadcast, 

Foliar WP 0.0744-0.075 5 0.3719 NS 7 

COTTON 

(UNSPECIFIED)

3

Broadcast, 

Foliar 

WDG, 

WP, L 0.0994-0.1006 NS, 4 0.3994-0.04061 NS 7 

CRABAPPLE

4 Broadcast, 

Foliar 

SC, 

Solid 0.1488 - 0.15 NS NS NS, 0.5438 12 

CRANBERRY Broadcast, 

Foliar 

WDG, 

WP 0.1294-0.1313 2 0.2588-0.2625 NS 7 

CUCURBIT 

VEGETABLES 

Broadcast, 

Foliar, Bloom 

WDG, 

WP 0.0994-0.1006 5 0.4969-0.5031 NS 5 

DECIDUOUS 

FRUIT TREES 

(UNSPECIFIED)

4

Broadcast, 

Foliar 

SCSolid, L 0.1488-0.1529 NS NS NS, 0.5438 7, 12 

FRUITING 

VEGETABLES 

Broadcast, 

Foliar 

WP, 

WDG 0.0744-0.075 4 0.2975-0.3 NS 7 

GRAPES Broadcast, 

Foliar WDG 0.0994-0.1006 2 0.1988-0.2013 NS 14 

LEAFY 

VEGETABLES 

Broadcast, 

Foliar 

WP, 

WDG 0.0744-0.075 5 0.3719-0.375 NS 7 

LEGUME 

VEGETABLES 

Broadcast, 

Foliar 

WDG, 

WP 0.0994-0.1006 3 0.3-0.3019 NS 7 

MUSTARD Seed 

Treatment L-RTU 0.5039 lbs ai / lbs seed NS NS NS NS 

ONION Broadcast, 

Foliar 

WDG, 

WP 0.1488 -0.15 4 0.5994-0.6 NS 7 

ORNAMENTAL 

AND/OR SHADE 

TREES, 

HERBACEOUS 

PLANTS 

Broadcast, 

Foliar 

L, SCsolid 0.1488-0.1529 NS NS NS, 0.5494 7, 12 

ORNAMENTAL 

WOODY SHRUBS 

AND VINES 

Broadcast, 

Foliar L 0.1529 NS NS NS 7 

PEAR4 Broadcast, 

Foliar 

SCsolid 0.1488-0.15 NS NS NS, 0.5438 12 

PEAS, 

SUCCULENT 

Broadcast, 

Foliar 

WDG, 

WP 0.0994- 0.1006 3 0.3-0.3019 NS 7 

PINE SEEDLINGS Broadcast, 

Foliar L 0.1529 NS NS NS 7 

POME FRUITS 

Broadcast, 

Foliar, Pink 

to Bloom, 

WP, 

WDG 0.1488-0.15 NS, 4 0.5906-0.6 NS 12 
20 

Use Site 

Application 

Method, 

Timing 

Form 

Max Single 

App. Rate 

(lbs ai/A) 

Max # 

Apps / 

CC 

Max App 

Rate/CC 

(lbs ai/A) 

Max App 

Rate/Year 

(lbs ai/A) 

Minimum 

Treatment 

Interval 

(days) 

Petal Fall 

POTATO, 

WHITE/IRISH 

Seed 

Treatment L-RTU 0.0098 lbs ai / lbs seed NS 0.2945 NS NS 

POTATO, 

WHITE/IRISH, 

ROOT AND TUBER 

VEGETABLES 

Broadcast, 

Foliar 

WDG, 

WP 0.744-0.075 4 0.3-0.3063 NS 7 

SMALL FRUITS Broadcast, 

Foliar 

WDG, 

WP 0.0994-0.1006 2 0.1988-0.2013 NS 14 

SMALL FRUITS Broadcast, 

Foliar 

WDG, 

WP 0.1294-0.1313 2 0.2588-0.2625 NS 7 

SOYBEANS 

(UNSPECIFIED)6

Broadcast, 

Foliar FC 0.0407 2 0.0814 NS 7 

STONE FRUITS 

Broadcast, 

Foliar, 

Dormant, 

Delayed 

Dormant, 

Petal Fall 

WDG, 

WP 0.1488-0.15 4 0.595-0.6 NS 10 

STRAWBERRY Broadcast, 

Foliar 

WDG, 

WP 0.1294-0.1313 2 0.2588-0.2625 NS 7 

TOBACCO Broadcast, 

Foliar 

WDG, 

WP 0.0744-0.075 4 0.2975-0.3 NS 7 

TOMATO 

Chemigation, 

Soil drench 

treatment 

L, SCsolid 0.0075-0.0076 

lbs/plant NS, 1 NS NS NS 

TREE NUTS Broadcast, 

Foliar 

SCsolid 0.1488-0.15 NS NS NS, 0.5438 12 

TREE NUTS 

Broadcast, 

Foliar, 

Dormant, 

Delayed 

Dormant 

WP, 

WDG 0.1794-0.18 4 0.7175-0.72 NS 14 

Max.=maximum; form=formulation, App=application; WDG=water dispersible granule, FC=flowable concentrate; 

WP=wettable powder; EC=emulsifiable concentrate; L-RTU=liquid-ready to use; SC-Solid=soluble 

concentrate/solid; L=liquid; cc=crop cycle; NS=not specified; A&K=attract-and-kill device 

*Can be applied to all uses sites using aerial, airblast, or ground equipment, except for the seed treatment uses. The 

maximum number of applications per year was not specified on labels. 

1

 May only be used in ID, UT, WY. 

2

 May only be used in NV, WA, ID. 

3

 Some labels restrict use to CA, FL, GA, NC, SC, VA. 

4

 Only allowed for use in WA. 

5

 SC-solid may only be used in WA. 

6

 Buffer Restrictions 

7

 May only be used in OR. 
21 

EPA registration number WA110010 allows for control of apple maggot in non-agricultural 

quarantine and pest free areas (including residential areas) under order for Apple Maggot as 

Specified under WAC 16-470. The product is used on apples, crabapples, pears, ornamental 

plants and trees, and non-bearing fruit and nut trees. The product is applied to give the tree 

uniform spray coverage of the plant. The label does not have a maximum single application rate. 

It does indicate that the product may be applied every 12 days, up to 4 times a year, with a 

maximum of 0.55 lbs ai/A per year. 

There are several products registered for use on a variety of sites without a specified maximum 

single application rate, maximum number of applications per crop cycle or year, maximum 

number of applications, or minimum retreatment interval. 

5.3. Use on Trees 

Three different labels allow for use as tree injections or basal bark treatments (EPA Reg No. 

8033-94 and 8033-106) on ornamental and non-bearing fruit and nut trees. One of the labels 

(EPA Reg No. OR09005) is an attract-and-kill device to control carpenter worm in poplar trees. 

The device is applied with a string to trees where acetamiprid wettable powder is mixed with a 

grease and pheromone. This use is assumed to result in minimal exposure to aquatic organisms. 

Tree injection uses allow for 0.0024 – 0.0025 lbs ai per inch diameter at breast height (DBH). 

Basal bark treatments involve wetting the bark of the tree starting from a height of approximately 

eight feet downwards to the exposed root flair with a directed spray to completely wet the 

application area. Basal bark treatments recommend applications at 0.004 lbs per inch DBH of 

the intended target. Also recommend use of 0.15 lbs ai/36-42 total inches of treatment DBH, 

depending on the bark. Only single application rates are provided on the labels. 

Table 5-3. Summary of Use Pattern Recommended for Control of Borers, Scale Insects, 

and Hemlock Wooly Adelgids in Ornamental or Non-Bearing Fruit and Nut Trees 

Use Site Application 

Method Timing Formulation Single Application Rate Recommendations 

Hybrid Poplar Device applied to 

tree with string 

Spring and 

Summer 

Attract-andkill Device 0.00000265 lbs ai/A 

Ornamental and Nonbearing Fruit and Nut 

Trees 

Tree injection 

treatment 

Bud break 

through foliar L, SC-solid 0.0024 - 0.0025 lbs ai/DBH 

Basal bark 

treatment 

Bud break 

through foliar 

(Mid Spring) 

L NS, 0.004 lbs ai/DBH 

0.15 lbs ai/ gal/36-42 DBH 

L=liquid; SC-solid=soluble concentrate, solid; DBH=diameter breast height in inches; gal=gallon 

5.4. Termiticide, Ants Control, and Control of Pests 

 A number of products are registered for use of control of termites, ants, and various other insects 
22 

around homes, buildings, eating establishments, animal production sites, equipment, ships and 

boats, transportation facilities, paths, patios, and wood protection treatment, etc. The uses 

involve surface application to soils, mound treatments, drench treatments, perimeter treatments, 

soil injection, trenching, rodding, void treatments, spot treatments, soil excavation treatments, 

crack and crevice treatments, drench, bait applications, mound treatments, and insecticidal strip 

treatments. Some termiticide products are applied to subsurfaces into piping and reticulation 

delivery systems. Soil excavation involves digging up soil, treating it, and then reapplying it. 

Rodding involves drilling a series of holes (no more than 12 inches apart) into the ground, 

injecting the pesticide, and then covering the hole. Trenching (may be 6 inches deep and wide) 

involves digging a trench around a structure and treating the trench, Often trenching and rodding 

are both used in treatments. Perimeter treatment may be up to 10 feet wide around the structure 

and up to 3 feet high on the structure. No information was available on application intervals or 

maximum number of applications per year. 

Table 5-4. Summary of Uses Around Buildings, Paths, Wood, and Equipment 

Application Method Application Timing Formulation Maximum Single Application 

Rate 

Application Rates in lbs ai/A 

Crack and crevice and/or spot 

treatment When needed SC-Solid 0.3659 lbs ai/A 

Soil drench treatment, spray, crack 

and crevice treatment, spot treatment, 

void treatment, perimeter treatment 

When needed SC-solid, WP, EC 0.1829 - 0.189 lbs ai/A 

Barrier treatment When needed SC-Solid 1.1 lbs ai/A 

Barrier treatment, soil surface 

treatment, barrier treatment 

Postconstruction, 

preconstruction WP, EC 18.6-18.7 lbs ai/A 

Drench When needed EC 23.4 lbs ai/A 

Application Rate per Spot 

Crack and crevice and/or spot 

treatment When needed 

Bait 0.00000083 lbs ai/ spot 

Bait 0.00000165 lbs ai/ spot 

Bait 0.00000386 lbs ai/ spot 

Applications Rates for Baits in Bait Stations 

Bait application When needed 

Bait 0.00001531 lbs ai/ bait station 

Bait 0.00002344 lbs ai/bait station 

Application Rates in lbs ai per linear foot 

Soil treatment (subslab injection, 

trenching), soil excavation, spray, 

void treatment 

When needed, 

postconstruction, 

preconstruction 

EC, WP 0.0009 lbs ai/ linear ft 

EC, WP 0.0017 lbs ai/linear ft 

Application Rates in lbs ai/gallon 

Crack and crevice treatment, void 

treatment, spot treatment, foam 

application, void treatment, soil 

injection 

When needed 

EC, WP, WDG 0.0043 lbs ai / 1 gal 

SC-Solid, WP 0.105 lbs ai / 25 gal 

0.1065 lbs ai /25 gal 

Other Application Rates 

Mound Drench Cool weather (65 - 80 WP, EC 0.0043 lbs ai / mound 
23 

Application Method Application Timing Formulation Maximum Single Application 

Rate 

F) 0.0086 lbs ai / mound 

Spray, spot treatment, perimeter 

treatment When needed L-RTU, SC-solid No dosage conversion 

Bait application When needed Bait No dosage conversion 

Insecticidal strip treatment When needed IM No dosage conversion 

L-RTU=liquid-ready to use; SC-solid=soluble concentrate-solid; IM=impregnated material; EC=emulsifiable 

concentrate; WP=wettable powder; gal=gallon 

5.5. Usage Data 

Based on market usage data from 2000-2010, usage averaged approximately 60,000 lbs ai for 

900,000 acres treated resulting in an overall average application rate of 0.067 lbs ai/A (USEPA, 

2012) (Table 5-5). The screening-level use assessment (SLUA) estimate, which only considers 

agricultural use, indicate that 33% of the acetamiprid used is applied to apples and cotton 

(20,000 lbs ai/year on average). On average 2000 to 5000 lbs of acetamiprid per year is applied 

to pears, oranges, lettuce, strawberries, and grapes. Based on the maximum amount of crop 

treated, acetamiprid is important for pears, celery, strawberries, apples, grapes, and lettuce where 

on average greater than 15% of these crops are treated with acetamiprid. Values are calculated by 

merging pesticide usage data sources together, averaging across all observations, and then 

rounding.

Table 5-5. Screening Level Estimates of Agricultural Uses of Acetamiprid (099050), Sorted 

Alphabetically 

Crop 

Average Annual Pounds 

Active Ingredient Used on 

Crop 

Percent Crop Treated 

Average Maximum 

Alfalfa <500 <1 <2.5 

Almonds* <500 <1 <2.5 

Apples 20,000 25 40 

Artichokes* <500 N/C N/C 

Beans, Green <500 <1 <2.5 

Broccoli 1,000 10 15 

Brussels Sprouts* <500 N/C N/C 

Cabbage 1,000 10 15 

Caneberries <500 <2.5 5 

Cantaloupes <500 5 15 

Cauliflower <500 10 20 

Celery 1,000 35 45 

Cherries 1,000 5 15 

Chicory*+ <500 N/C N/C 
24 

Crop 

Average Annual Pounds 

Active Ingredient Used on 

Crop 

Percent Crop Treated 

Average Maximum 

Cotton 20,000 5 5 

Cucumbers <500 <2.5 <2.5 

Grapefruit <500 <2.5 5 

Grapes (all) 2,000 20 30 

Lemons <500 <2.5 5 

Lettuce 3,000 15 30 

Lima Beans <500 <1 <2.5 

Nectarines* <500 N/C N/C 

Olives*+ <500 N/C N/C 

Onions <500 5 5 

Oranges 4,000 <2.5 10 

Peaches 1,000 5 10 

Pears 5,000 35 60 

Pecans <500 <1 <2.5 

Peppers <500 5 15 

Pistachios <500 <1 <2.5 

Potatoes 1,000 <2.5 <2.5 

Prunes <500 5 5 

Pumpkins <500 5 5 

Spinach <500 10 20 

Squash 1,000 <2.5 <2.5 

Strawberries 3,000 30 50 

Tobacco <500 <1 <2.5 

Tomatoes 1,000 5 10 

Walnuts 1,000 5 10 

Watermelons <500 <1 <2.5 

All numbers rounded. 

<500 Less than 500 pounds of active ingredient 

<2.5 Less than 2.5 percent of crop treated 

<1 Less than 1 percent of crop treated 

N/C Only lbs.ai available 

* Based on CA DPR data only (valid because 95% or more of U.S. acres grown are in California) 

+ Crops not known to be listed on active end use product registrations or as Section 18 emergency 

exemptions when this report was run 

 

SLUA data sources include: 

USDA-NASS (United States Department of Agriculture's National Agricultural Statistics Service) 

Private Pesticide Market Research 

California DPR (Department of Pesticide Regulation) 
25 

Figure 5-1 spatially represents acetamiprid agricultural use intensity in the U.S.; use intensity is 

highest in parts of the Southwest (CA and AZ), Northwest (WA and OR), and Northeast (NY, 

PA, and MI). 

Figure 5-1. Average Pounds Acetamiprid Used by Crop Reporting District (2006-2010).8

 

8 This map was developed by BEAD (USEPA, 2012). This is a map of agricultural pesticide usage at the 

Crop Reporting District (CRD) level; CRDs are aggregates of counties created by USDA NASS (USDA, 

2010). Pesticide usage is displayed as average pounds (for the years 2006-2010) per 1,000 acres of farmland 

in a CRD to normalize for the variation in farmland between CRDs. Farmland acreage was obtained from 

USDA (2007). 

Usage is based on private market surveys of pesticide use in agriculture (Proprietary Data, 2006-2010). The 

survey data are limited to the states that represent the top 80-90% of acreage for the individual crops; 

therefore, use may be occurring in regions outside the scope of the survey. CRDs showing no usage of 

pesticides may be due to either the lack of pesticide use in the region or non-participation in the agricultural 

surveys. In addition, across the years, there may be variations in the specific crops included in the CRD 

survey. This may result in a lower annual average for the CRD. 

Sources: Proprietary Data, 2006-2010; USDA NASS Crop Reporting Districts, 2006-2010; USDA Census of 

Agriculture, 2007.
26 

6. Environmental Fate and Transport 

6.1. Summary 

Acetamiprid may enter the environment via spray directly onto soil or foliage, via spreading of 

bait on surfaces, or via injection into soil and building foundations. It may move off-site via 

spray drift, leaching, and runoff. Acetamiprid is considered nonvolatile from dry non-adsorbing 

surfaces, water, and moist soil. It is not likely to bioconcentrate in aquatic or terrestrial 

organisms. Chemicals with half-lives greater than 60 days in soil, water, and sediment are 

considered persistent (USEPA, 2008b); therefore, aerobic aquatic and soil metabolism half-lives 

for acetamiprid indicate that acetamiprid is not persistent. However, there is uncertainty in the 

half-lives due to significant amounts of unextracted, unidentified residues in the metabolism 

studies. If these unidentified residues were found to be parent, then the compound would be 

classified as persistent.9 Primary routes of degradation are via aerobic soil and aerobic aquatic 

metabolism. Acetamiprid is stable to hydrolysis at 25o

C and aqueous photolysis is not an 

important degradation pathway. Acetamiprid is classified as moderately mobile using the FAO 

classification system (Kocs = 157-298 L/kg organic carbon) and may be transported into surface 

and ground water. Acetamiprid has nine (excluding carbon dioxide) identified degradates, five 

of which are major degradates. Four of the five major degradates have the pyridylmethylamine 

structure and one minor degradate contains both the pyridylmethamine structure and the cyano 

group of the parent. Residues of concern for human health drinking water were identified by the 

Health Effects Division to be the parent only. Residues of concern for aquatic organisms were 

determined to be the parent and IM 1-410 by the Environmental Fate and Effects Division. As 

some of the unextracted residues may be the parent compound or IM 1-4, unextracted residues 

were determined to be a residue of concern for both human health drinking water and aquatic 

organisms by the Environmental Fate and Effects Division. 

Acetamiprid has a log dissociation constant (pKa) of 0.7 for the protonated form, indicating that 

its form will not change significantly at environmentally relevant pH values. The vapor pressure, 

air-water partition coefficient (KAW), and ratio of acetamiprid concentration in moist soil to 

acetamiprid concentration in air (Cwater+soil/Cair) indicate that it is nonvolatile from dry nonadsorbing surfaces, water, and moist soil using OPPTS11,12 Guideline 835.6100 classifications. 

The log octanol-water partition coefficient (log Kow) is 0.08 at 25o

C and the log octanol-air 

partition coefficient (log KOA) is 12.5 indicating it is not likely to bioconcentrate in aquatic or 

terrestrial organisms (Armitage and Gobas, 2007; Gobas et al., 2003; USEPA, 2009c). 

Table 6-1 summarizes the identity information and physical-chemical properties of acetamiprid. 

Table 6-2 summarizes other environmental fate data for the parent and provides half-lives for the 

 

9

 Data indicates that some of the unextracted residues are unlikely to be parent; however, it is unknown what portion 

is parent and what portion is not. 

10 IM-1-4 retains the pyrimidylmethylamine structure of the parent. 

11 Office of Prevention, Pesticides, and Toxic Substances (OPPTS) is now the Office of Chemical Safety and 

Pollution Prevention (OCSPP); however, the guidelines still reference OPPTS and so the guidelines are referenced 

with OPPTS in this document. 

12 A list of all OPPTS Guidelines discussed in this document is available in Appendix D. 
27 

parent and unextracted residues. Table 6-6 summarizes half-lives for the parent alone, residues 

of acetamiprid and IM 1-4, and residues of acetamiprid, IM 1-4, and unextracted residues. All of 

these half-life values are used to characterize estimated environmental concentrations (EECs) in 

water. 

Table 6-1. Summary of physical-chemical properties of acetamiprid 

Parameter Value Source Comments 

PC Code 099050 None None

CAS Number 135410-20-7 (USNLM, 2009) None

Structure 

 None

Chemical Name N1

-[(6-chloro-3-pyridyl)methyl]-N2-cyanoN1

-methylacetamidine MRID 44651803 None

Molecular Weight 222.68 MRID 44651803 None

Water Solubility 4250 mg/L (25°C) MRID 44651811 None

Vapor Pressure 

<1 x 10-8 Torr at 25o

C MRID: 46235701 Nonvolatile from dry 

non-adsorbing surfaces 

(USEPA, 2010a)

7.50 x 10-10 Torr at 25oC

1 X 10-4 mPa at 25o

C (AERU, 2012)

Henry’s Law 

constant 

5.2 x 10-14 atm-m3

/mol at 25oC

(estimated)

(Estimated from vapor 

pressure

and water solubility at 

pH 7 and 20o

C)

Calculated with vapor 

pressure reported by 

AERU (2009).

Dissociation 

Constant (pKa) 0.7 at 25o

C (USEPA, 2002) None

Log KOW 0.8 at 25oC MRID 44651883

Not likely to 

bioconcentrate 

(USEPA, 2010a)

Air-water partition 

coefficient (KAW) 2.11 x 10-12 (log KAW = -11.68) Calculated1 Non-volatile from 

water (USEPA, 2010a)

Octanol-air partition 

coefficient (KOA) 3.0 x 1012 (log KOA = 12.5) Calculated1

Not likely to 

biomagnify in 

terrestrial food chains2

(Gobas et al., 2003; 

USEPA, 2009c)

Cwater+soil/Cair 2.63 x 1011 to 2.02 x 1012 Calculated1

Non-volatile from 

moist soil (USEPA, 

2010a)

1

All estimated values were estimated according to “Guidance for Reporting on the Environmental Fate and 

Transport of the Stressors of Concern in Problem Formulations for Registration Review, Registration Review Risk 

Assessments, Listed Species Litigation Assessments, New Chemical Risk Assessments, and Other Relevant Risk 
28 

Assessments” (USEPA, 2010a). 2

 A recent FIFRA Scientific Advisory Panel (SAP) reported, “Gobas et al (2003) concluded that chemicals with a 

log KOA >5 can biomagnify in terrestrial food chains if log KOW >2 and the rate of chemical transformation is low. 

However, further proof is needed before accepting these limits without reservations” (USEPA, 2009c). This was 

also supported by Armitage and Gobas’s work completed in 2007 (Armitage and Gobas, 2007). 

Table 6-2. Summary of environmental fate and transport properties of acetamiprid6

Parameter Value(s)

Source / 

Study 

Classification

Comments 

Hydrolysis3 (days)

Half-life, linear regression1:

Stable (pH 5, 7, 9 at 25o

C)

50.8 (pH 9 at 35oC)

12.8 (pH 9 at 45o

C)

MRID 

44651876

Acceptable

None

Atmospheric 

Degradation (days)

Half-life:

0.140 (estimated)

(USEPA, 

2009b)

NA 

Estimated Hydroxyl Radical Reaction 

Half-life for a 12-hour day; 1.5x106

 OH 

molecules/cm3

 Using EPIWeb Version 4.0

Aqueous Photolysis 

Half-life (days)

Half-life, linear regression1:

342 (pH 7, 25oC)

MRID 

44988509

Acceptable

None

Soil Photolysis Halflife4 No half-lives available

MRID 

48563501

Supplemental –

not for use in 

modeling

Microbial activity was higher in the dark 

control than in the irradiated samples and 

the degradation was faster in the dark 

control. As soil photolysis did not occur 

at a faster rate than microbial degradation, 

photolysis will not be a major route of 

degradation when microbial degradation is 

occuring. It is not known whether 

degradation was faster in the dark control 

due to the differences microbial activity. 

The study provides evidence on 

degradation products that may be observed 

with irradiation.

Aerobic Soil 

Metabolism Half-life 

(days)

Half-life, nonlinear regression1 at 

20o

C:

Parent Only:

1.1, sandy loam

1.2, clay loam

1.0, clay loam

Parent+Unextracted Residues 

76, sandy loam 

75, clay loam 

99, clay loam 

MRID 

46255603

Supplemental –

May be used in 

modeling

Only one replicate. Unextracted residues 

made up <1 to 31 % of applied 

radioactivity.
29 

Parameter Value(s)

Source / 

Study 

Classification

Comments 

Half-life, nonlinear regression1 at 

20oC:

Parent Only:

2.8, sandy loam

0.90, silty clay loam

6, clay loam

Parent+Unextracted Residues: 

10, clay loam 

MRID 

44651881

Supplemental –

May be used in 

modeling

 Unextracted residues made up 

approximately 20-40% at the end of the 

study (182 days); however, unextracted 

residues were not observed until most of 

the parent had degraded in the silty clay 

loam and sandy loam suggesting that the 

unextracted residues were not the parent 

compound.5

Half-life, nonlinear regression1 at 

20o

C:

Parent Only:

1.4, loamy sand

Parent+Unextracted Residues: 

2.0, loamy sand 

MRID 

44699101

Supplemental –

May be used in 

modeling

 Unextracted residues ranged from 2 to 

17% of applied radioactivity. The identity 

of the unextracted residues is not known.

Half-life, linear regression1 at 25oC:

Parent Only: 

0.3, loamy sand

MRID 

44651880

Supplemental –

Not for use in 

modeling

Not conducted under GLP. Unextracted 

residues were high (up to 14%)

Half-life, linear regression1 at 25oC:

Parent Only:

3.5, loamy sand

Parent+Unextracted Residues: 

6.4, loamy sand 

MRID 

44651879

Acceptable

Biphasic degradation was observed with 

an initial 3.6 day half-life followed by a 75 

day half-life. Unextracted residues were 

up to 20%.

Anaerobic Soil 

Metabolism Half-life 

(days)

No half-lives available

MRID 

48554501

SupplementalNot for use in 

modeling

Dissolved oxygen concentrations ranged 

from 1.87-1.94 mg/L, indicating system 

was not fully anaerobic. Data on 

degradates can be used as the environment 

is expected to occur in natural systems.7

 

Aerobic Aquatic 

Metabolism Half-life 

(days)

Half-life, nonlinear regression1

 at 

25o

C:Parent Only:

25, loamy sand sediment

Parent+Unextracted Residues: 

74, loamy sand sediment 

MRID 

44988513

Acceptable

Maximum of 38% unextracted residues. 

The identity of the unextracted residues is 

not known. Data available for only one 

sediment.
30 

Parameter Value(s)

Source / 

Study 

Classification

Comments 

Anaerobic Aquatic 

Metabolism Half-life 

(days)

Half-life, linear regression1 at 25oC:

Parent Only: 325, loamy sand 

sediment

Parent+Unextracted Residues: 568, 

loamy sand sediment 

MRID 

44988512

Acceptable

Data available for only one sediment.

Solid-water 

distribution coefficient 

(Kd) in L/kg

Average Kd at 20o

C

0.39, loamy sand, pH 4.4 

3.9, loamy sand II, pH 6.2 

1.1, silt loam, pH 6.6 

3.5, clay, pH 7.5 

4.1, sandy loam sediment, pH 5.6 

Mean = 2.60 (standard 

deviation=1.72) 

MRID 

44651883

Acceptable

Coefficient of variation is 66%.

Freundlich solid-water 

distribution coefficient 

(KF) in L/kg

K F (1/n) at 20o

C

Parent: 

0.33 (0.85), loamy sand, pH 4.4 

3.0 (0.82), loamy sand II, pH 6.2 

1.0 (0.90), silt loam, pH 6.6 

3.2 (0.91), clay, pH 7.5 

3.2 (0.83), sandy loam sediment, 

pH 5.6 

MRID 

44651883

Acceptable

Sorption was dependent on concentration 

in some soils.

Organic-carbon 

normalized 

distribution coefficient 

(Koc) in L/kgorganic carbon

Average Koc at 20o

C

157, loamy sand, pH 4.4 

266, loamy sand II, pH 6.2 

251, silt loam, pH 6.6 

298, clay, pH 7.5 

164, sandy loam sediment, pH 5.6 

Mean = 227 (standard 

deviation=63.26) 

MRID 

44651883

Acceptable

Coefficient of variation is 28%. The 

coefficient of variation is less than that for 

Kd values indicating that Koc values will 

be better at predicting sorption across soils 

than Kd values. Moderately mobile 

according to FAO classification.

Terrestrial Field 

Dissipation Half-life 

(days)

Half-life, nonlinear regression1

:

2.8, CA, Gilman loamy fine, Vinca 

rosea

14.1, FL, Astatula fine, tree ferns

4.2, NJ, Penn silt loam, garden 

mums

MRID 

44988514

Supplemental

Wettable powder 70% ai (EXP80667A 

70WP). Degradate IM 1-2 converted to 

IM 1-4 in storage stability study and IM 1-

4 was not stable. Residues in plants were 

not reported. Broadcast at 0.15 lbs ai/A 

with four applications. Parent was not 

detected below 15 cm. ECM/ILV for soil 

are 44988516/44988517.
31 

Parameter Value(s)

Source / 

Study 

Classification

Comments 

Half-life, linear regression1:

3, WA, Timerman coarse sandy 

loam, apples

6, FL, Candler sand soil, oranges

13, NY, Oakville loamy fine sand, 

cabbage

6, CA, Romona loam soil, cotton

MRID 

44988515

Supplemental

Wettable powder 70% ai (EXP80667A 

70WP). Degradate IM 1-2 converted to 

IM 1-4 in storage stability study and IM 1-

4 was not stable. Residues in plants were 

not reported. Broadcast at 0.15 lbs ai/acre 

with four applications. Parent was not 

detected below 15 cm. Conditions not 

favorable to leaching. Subset of data used 

to estimate half-life for FL and WA site. 

ECM/ILV for soil are 

44988516/44988517.

Half-life, linear regression1:

10.1, Prince Edward Island, Alberry 

sandy loam

5.2, Ontario, London loam

17.8, Manitoba, Ryerson clay loam

MRID 

44988625

Supplemental

Wettable powder 70% ai (EXP61486A). 

Pan evaporation data were not reported so 

water balances could not be determined. 

Storage stability data were not submitted 

for the test site soils. Acetamiprid was 

applied four times at 168 g ai/ha with a 7 

day interval to bare plots in Canada. 

Parent not detected below 15 cm depth. 

ECM/ILV for soil are 

44988516/44988517.

Environmental 

Chemistry Methods 

and Independent 

laboratory Validation

LC/MS/MS for detection of 

acetamiprid, IM 1-2, IC-0 in soil

MRID 

44988516/

44988517

Satisfactory

Acetamiprid, IC-0, IM 1-4

LOD = 3.33 μg/kg-soil

Acetamiprid, IM 1-2, IC-0, 1M-1-4

LOQ = 10 μg/kg-soil

HPLC-UV for parent, IC-0, IM 1-4, 

IM 1-2 in water

MRID 

44988536

LOD = 0.033 μg/L

LOQ=0.1 μg/L 1

 Degradation kinetics were calculated using the single first order decay equation using either nonlinear regression 

of non-transformed data or linear regression of natural log transformed data. 

2

 Value corrected to represent natural sunlight at 40oN latitude. 3

 MRID 44651877 is supplemental. A material balance was not conducted in the study; however, the results suggest 

that degradates IM-1-4 and IC-0 are stable. 

4

 MRID 44988508 is unacceptable. 5

 This indicates that the unextracted residues were not the parent compound. Unextracted residues in the clay loam 

appeared as the parent was lost the identity of unextracted residues is unknown. 

6

 This table shows half-lives for the parent and parent plus unidentified unextracted residues which may or may not 

be the parent. These values are relevant in understanding the uncertainty in data due to unextracted residues. Table 

6-6 summarizes half-lives calculated for acetamiprid plus IM 1-4 plus unextracted residues which will be used in the 

calculation of modeling inputs in the ecological risk assessment. 

7

 Unextracted residues were at a maximum of 36.1% in the clay loam and 30% in the sandy loam soil. The identity 

of the unextracted residues is not known. Data only available on two soils. Results on four soils are recommended. 

6.2. Degradation/Transformation of Parent 

The persistence of acetamiprid is uncertain because a large portion of residues in the metabolism 

studies were unidentified; however, the overall evidence suggests it is not persistent in aerobic 

systems. Aerobic soil metabolism rates for the parent alone and for the parent and unextracted 
32 

residues in some soils indicate acetamiprid is not persistent.13 However, if it is assumed that all 

of the unextracted residues are the parent compound, acetamiprid would be considered persistent 

in some systems. Evidence suggests that not all of the unextracted residues are the parent 

compound; however, it is unknown what portion of the unextracted residues are parent and what 

portion are not. As many of the values considering both parent and unextracted residues are 

lower than 10 days; it is likely that acetamiprid is not persistent in aerobic systems. Under 

anaerobic aquatic conditions acetamiprid is persistent. 

Acetamiprid was stable to hydrolysis at 25o

C and pH 5, 7, and 9; however, hydrolysis was 

observed at pH 9 at 35 and 45o

C (MRID 44651876). The aqueous photolysis half-life of 34 days 

indicates that aqueous photolysis is a minor degradation pathway (MRID 44988509). Rates of 

soil photodegradation are not available.14

The primary route of degradation for the parent compound is aerobic soil metabolism. There is 

uncertainty in the degradation of acetamiprid due to high levels of unextracted residues in 

metabolism studies. Therefore, to assess the impact of this uncertainty on the risk assessment, 

degradation rates were estimated in two ways: for the measured parent by itself, and for 

measured parent plus unextracted residues under the assumption that unextracted residues are 

also parent compound or are a residue of concern. Half-lives were also calculated for these 

combinations along with N-methyl(6-chloro-3-pyridyl)methylamine (IM 1-4) because the IM 1-4 

degradate is considered a residue of concern for aquatic organisms; IM 1-4 is not considered a 

residue of concern for human health drinking water residues. In nine soils, aerobic soil 

metabolism rates for the parent ranged from <1 day to 6 days for the parent alone, and from 2 to 

99 days for the parent plus unextracted residues. This difference in half-lives is environmentally 

relevant and impacts the EECs and EDWCs (see Section 14.1.B for more discussion). Anaerobic 

soil metabolism half-lives are not available. Aerobic aquatic metabolism rates were slower than 

aerobic soil metabolism rates. The aerobic aquatic half-life was 25 days for the parent, and 74 

days for parent plus unextracted residues in one sediment (MRID 44988513). Anaerobic aquatic 

metabolism was much slower, with a half-life of 325 days in a loamy sand sediment (MRID 

44988512). Examination of aerobic aquatic and anaerobic aquatic metabolism in two sediments 

representative of intended use sites are recommended by OPPTS Guideline 835.4300; however, 

data are only available on one sediment for both of the studies. 

6.3. Field Dissipation 

The terrestrial field dissipation of acetamiprid was studied at seven U.S. sites on various crops, 

and on bare ground plots at three sites in Canada. The application rate used in all studies was 

0.15 lbs ai/A. This is lower than the maximum single application rate for use on citrus--0.25 lbs 

ai/A/single application, which has the highest single application rate among agricultural uses, a 

maximum of five applications/season, and a maximum of 0.55 lbs ai/A/season (several other 

 

13 International half-lives that are considered persistent in soil, water, and sediment range from greater than 60 days 

to greater than 365 days (USEPA, 2008b). 

14 A soil photolysis study (MRID 48563501) is available; however, data were insufficient to determine the rate of 

soil photolysis. 
33 

fruit and nut tree crops have similar or slightly higher seasonal application rates). The 

dissipation half-lives for acetamiprid applied to domestic food, fiber and ornamental crops 

ranged from three to 14 days for residues in 0 to 15 cm (MRIDs 44988514, 44988515). The 

dissipation half-lives for acetamiprid applied to bare ground plots (determined in Canadian soils) 

ranged from five to18 days (MRID 44988625). The submitted studies generally met guideline 

requirements. However, because the degradate IM 1-2 converts to IM 1-4 in frozen storage 

within a short period of time (approximately 1 month), and many of the samples were stored for 

much longer periods of time (over 600 days, lengths of storage for which storage stability data 

were not reported) prior to analysis, the patterns of formation and decline could not be 

determined accurately for these major degradates. Also, at several of the study sites, negative 

water balances (i.e., greater evaporation/total water loss from the soil than the total water input) 

following the final application likely precluded the possibility of significant leaching. Soil 

characteristics and results of the field studies are presented in Table 6-3. All reported maximum 

values for degradates in Table 6-3 are for the period following the final application and represent 

individual replicates (U.S. sites) or replicate means (Canadian sites) from the 0- to 15-cm depth. 

The degradate IM 1-4 frequently had higher maximum concentrations in soils than the parent. In 

the studies conducted on cropped sites, IM 1-4 was detected at its maximum levels generally 

within two weeks of application. These IM-1-4 conclusions are uncertain because of the storage 

stability issue. 

Table 6-3. Summary of Terrestrial Field Dissipation Study Results For Acetamiprid 

MRID Soil 

Texture 

Study Site, 

Crop 

Half-life in 

days 

Max. Depth 

of Leaching 

Maximum Concentration Observed in Soil 

(μg/kg-soil) 

Acet. IM 1-42 IM 1-22 IC-0 

44988515 sandy 

loam 

WA, apples 3 0-15 cm 

(a,b,c)3 148 149 29 ND4

44988515 sand FL, oranges 6 0-15 cm 

(a, b) 

77 60 ND ND 

44988515 loamy 

sand 

NY, cabbage 13 0-15 cm 

(a, b) 

107 197 ND ND 

44988515 loam CA, cotton 6 0-15 cm 

(a, b, c); 

15-30 cm (d) 

68 202 20 18 

44988514 loamy 

sand 

CA, 

vincarosea 

3 0-15 cm 

(a, b, c); 

30-45 cm (d) 

46 425 26 45 

44988514 sand FL, tree ferns 14 0-15 cm 

(a, b, d) 

151 147 ND 12 

44988514 silt loam NJ, garden 

mums 

4 0-15 cm 

(a, b, d) 

96 191 ND 23 
34 

MRID Soil 

Texture

Study Site, 

Crop

Half-life in 

days

Max. Depth 

of Leaching

Maximum Concentration Observed in Soil 

(μg/kg-soil) 

44988625 sandy 

loam 

Prince Ed. 

Isl., CAN., 

Bare ground 

10 0-15 cm 

(a, b, c, d) 331 135.0 17.0 14.5 

44988625 loam Ontario, 

CAN. 

5 0-15 cm 

(a, b, c, d) 

202.5 82.0 87.5 34.5 

44988625 clay 

loam 

Manitoba, 

CAN., bare 

ground 

18 0-15 cm 

(a, b, c, d) 209.0 41.0 68.0 17.5 

1 Acetamiprid was applied at all sites using four applications at intervals ranging from 6 to 9 days. 

2 IM 1-2 converts to IM 1-4 under storage conditions. IM 1-2 concentrations shown are likely to be lower than those 

that occurred in the field. 

3 a = parent; b = IM-1-4; c = IM-1-2; d = IC-0. 

4 ND = not detected. 

6.4. Degradates/Transformation Products 

Transformation products resulting from the environmental degradation of acetamiprid are: 

 N-methyl(6-chloro-3-pyridyl)methylamine (IM 1-4) 

 (E)-N1-[(6-chloro-3-pyridyl)-methyl]-N2-cyano-N1-methylacetamidine (IM 1-5) 

 6-chloronicotinic acid (IC-0) 

 N2

-carbamoyl-N1-((6-chloro-3-pyridyl)-methyl)-N1-methylacetamidine (IM 1-2) 

 6-chloro-3-pyridylmethano (IM-0) 

 N-((6-chloro-3-pyridyl)methyl)-N-methylacetamide (IM 1-3) 

 N-[(6-chloro-3-pyridyl)methyl]acetamide (IM 2-3) 

 N1-[(6-chloro-3-pyridyl)methyl]-N2-cyanoacetamidine (IM 2-1) 

 Carbon dioxide 

Structures of these degradates and the maximum percent of applied radioactivity present as the 

specified degradate is shown in are shown in Table 6-4 with additional information in Appendix 

A. Figure 6-1 provides structures and a proposed degradation pathway. In the studies 

containing soil or sediment, there was a significant amount of unextracted residues in many of 

the studies. As indicated earlier, this could result in an underestimation of the maximum amount 

for degradates. The degradates IM 1-4, IM 1-5, IC-0, IM 1-2, and IM 1-3 were present at greater 

than 10% applied radioactivity and are considered major degradates. All of these degradates 

except IC-0 contain the pyridylmethylamine in acetamiprid that is similar to other 

pyridylmethylamine nicotinoid insecticides (depicted in Figure 6-2) and observed in nicotine, 

which acts on the nicotinic acetylcholine receptor (Tomizawa and Casida, 2005). Degradates IM 

1-4, IM 1-5, and IM 1-3 were also relatively stable with peaks observed at the final sampling 

interval or high levels observed in studies over long durations. While IM-1-3 is relatively stable 

and is considered a major degradate based on the hydrolysis study (pH 9 with 35o

C and 45oC), it 

was only detected at maximums of 3-8% in the metabolism studies. Maximum concentrations of 

IM 1-4 were often higher than maximum concentrations of parent observed in the terrestrial field 
35 

dissipations studies (see Table 6-3). Toxicity data on transformation products are discussed in 

Section Table 8-4 and Table 8-7. Stressors of concern are identified in Section 9. 

Figure 6-1. Potential Degradation Pathway for Acetamiprid. Bold degradates had greater 

than 10% applied radioactivity associated with the compound in at least one submitted fate 

study. 
36 

Acetamiprid Imidacloprid Nitenpyram 

Thiacloprid Nicotine 

Figure 6-2. Structure of Pyridylmethylamine Nicotinoid Insecticides and Nicotine 

The 2009 new use assessment for acetamiprid identified IM 1-4 as a residue of concern for 

aquatic animals and it was assumed to have similar toxicity to the parent (USEPA, 2009, 

D364328). The only residue of concern for human health drinking water is the parent 

compound. Table 6-6 provides the half-lives estimated for parent with IM 1-4 and parent with 

IM 1-4 plus unextracted residues. Hydrolysis and aqueous photolysis data for IM 1-4 indicate it 

is stable to these degradation processes and that IM 1-4 has sorption coefficients similar to those 

of the parent (Table 6-2). Aerobic soil metabolism data show that residues of IM 1-4 were 

detected at high levels throughout the study for many of the soils with residues in three soils 

indicating that IM 1-4 was stable to aerobic soil metabolism.15 The maximum depth that IM 1-4 

was detected in terrestrial field dissipation studies was 15 cm. Appendix A contains additional 

environmental fate data submitted on IC-0. 

 

15 Three studies indicate that IM-1-4 is relatively stable to aerobic soil metabolism in some soils. In the aerobic soil 

metabolism study discussed in MRID 44651879, percent applied radioactivity associated with IM-1-4 was 73% at 

120 days and 60% at 365 days. In the aerobic soil metabolism study discussed in MRID 44651881 on a clay loam 

soil at 10o

C, percent applied radioactivity associated with IM-1-4 was 73% at 30 days and 54% at 178 days. In the 

same study (MRID 44651881) and soil (clay loam) at 20o

C, percent applied radioactivity was 56% at 14 days and 37 

at 182 days. 
37 

Table 6-4. Summary of Maximum Degradate Amounts in Environmental Fate Studies of Acetamipridd

Compound

Maximum Degradate % of Applied Radioactivity Associated with Compound (Time of Peak) 

Amount Detected at Final Sampling Interval in Corresponding Study

Hydrolysis Aqueous Photolysis Soil Photolysis Aerobic Soil Anaerobic Soil Anaerobic Aquatic Aerob

Aquat

IM 1-4 15 (35 d)a 15 (35 d)a ND 32 (24 d)a 32 (24 d)a 73 (120 d)c 61 (365 d)c 64 (61 d) 61 (125 d) 27 (270 d)a 27 (270 d)a 64 (60 d

34 (300 

IM 1-5 NA ND NA 22 (13 d)a 13 (182 d)b NA NA NA 

IC-0 NA ND 16 (24 d)a 16 (24 d)a 12 (7 d) ND (182 d) 3 (125 d)a 3 (125 d)a ND 19 (180 

ND (300 

IM 1-2 NA ND 1 (7 d) ND (24 d) 55 (7 d) ND (182 d) 4 (5 d) ND (125 d) 1 (90 d) ND (365 d) 21 (30 

<1 (300 

IM-0 NA ND ND 2.21 (7 d) ND (187 d) 2 (1 d) ND (125 d) NA NA 

IM-1-3 61 (35 d)a 61 (35 d)a ND 4 (24 d)a 4 (24 d)a 3 (60 d) <1 (365 d) 3 (5 d) 3 (125 d)a 8 (180 d) 6 (365 d) 1 (90 d

ND (300 

IM-2-1 NA NA 3 (17 d) 2 (24 d) NA ND NA NA IM-2-3 NA NA ND NA 2 (5 d) ND (125 d) NA NA 

NA=not analyzed; ND=not determined 

a Peak at final sampling interval in some studies b Peak at final sampling interval in some soils c High levels observed for > 100 days. d See Appendix A for more information on source of information in this table. 
38 

Table 6-5. Summary of environmental fate and transport properties of the acetamiprid 

degradate IM-1-4 

Parameter Value(s)

Source/ 

Study 

Classification

Comments 

Hydrolysis

(days) 

Stable (pH 4, 7, 9 at 50o

C) MRID 

44651877

Supplemental

Study duration was five days and at 50o

C. 

Greater than 99% of applied residues were 

IM-1-4 at the end of the study.

Aqueous Photolysis 

Half-life (days) 

Stable (pH 7, 25oC)

MRID 

44988511

Valid

None

Aerobic Soil 

Metabolism Slow degradation 

See results 

from studies 

conducted on 

parent

High levels observed for > 100 days

Aerobic Aquatic 

Metabolism Slow degradation Peak observed at study termination

Anaerobic Soil 

Metabolism Stable Little degradation over more than 60 days

Anaerobic Aquatic 

Metabolism Stable

Solid-water 

distribution 

coefficient (Kd) in 

L/kg 

Average Kd at 20o

C

0.38, loamy sand , pH 4.4 

6.48, loam sand II, pH 6.4 

5.63, silt loam, pH 6.6 

21.9, clay, pH 7.5 

4.08, sandy loam sediment, pH 5.6 

Mean = 7.69 (standard 

deviation=8.28) 

MRID 

44651885

Valid Coefficient of variation is 108%.

Freundlich solidwater distribution 

coefficient (KF) in 

L/kg 

K F (1/n) at 20o

C

0.29, loamy sand , pH 4.4 

5.35, loam sand II, pH 6.4 

4.34, silt loam, pH 6.6 

17.0, clay, pH 7.5 

2.84, sandy loam sediment, pH 5.6 

Mean = 5.97 (standard 

deviation=6.45) 

MRID 

44651885

Valid

Sorption was dependent on concentration 

in some soils. All 1/n values were less 

than 0.90.
39 

Parameter Value(s)

Source/ 

Study 

Classification

Comments 

Organic-carbon 

normalized 

distribution 

coefficient (Koc) in 

L/kgorganic carbon

Average Koc at 20o

C

153, loamy sand , pH 4.4 

440, loam sand II, pH 6.4 

1278, silt loam, pH 6.6 

1842, clay, pH 7.5 

163, sandy loam sediment, pH 5.6 

Mean = 775 (standard 

deviation=753) 

MRID 

44651885

Valid

Coefficient of variation is 97%. The 

coefficient of variation is less than that for 

Kd values indicating that Koc values will 

be better at predicting sorption across soils 

than Kd values. Moderately mobile to 

slightly mobile according to FAO 

classification.

 

Table 6-6. Summary of half-lives estimated for residues of parent, IM-1-4, and 

Unextracted residues in metabolism studies 

Type of Study 

(MRID) 

Study 

System 

Half-life (days)* 

Parent Only Parent + IM1-4 

Parent+IM-1-4+Unextracted 

Residues 

Aerobic Soil 

(44651881) 

Silty Clay 

Loam, 20o

C 0.9 1.1 1.1 

Clay Loam, 

20o

C 6 104 392 

Sandy Loam, 

20oC 2.8 118 299 

Aerobic Soil 

(46255603) 

Sandy Loam, 

20o

C 1.1 2.4 72 

Clay Loam, 

20o

C 1.2 2.4 67 

Clay Loam, 

20oC 1.0 1.7 84 

Aerobic Soil 

(44699101) 

Loamy Sand, 

20o

C 1.4 20 53 

Aerobic Soil 

(44651879) 

Loamy Sand, 

25o

C 3.5 430 895 

Aerobic 

Aquatic 

(44988513) 

Loam Sand, 

25o

C 25 215 658 

Anaerobic 

Aquatic 

(44988512) 

Loamy Sand, 

25o

C 325 590 1372 

*All values were estimated using nonlinear regression and the single first order equation. 

6.5. Mobility/Sorption 

Acetamiprid is classified as moderately mobile with organic carbon normalized soil-water 

distribution coefficients (Koc) ranging from 157 to 298 L/kgorganic carbon measured in four soils and 
40 

one sediment (MRID 44651883)16. The mean Koc was 227 L/kg-organic carbon and the 

coefficient of variation for Koc values (28%) is less than that for Kd values (66%) indicating that 

Koc values will be better at predicting sorption across soils than Kd values. Additionally, Kds 

tend to be higher as the percent organic carbon increases. There was no relationship with Kds 

and pH or percent clay. Based on the sorption coefficients and persistence, acetamiprid has the 

potential to reach ground water, especially in vulnerable sandy soils with low organic-carbon 

content and/or the presence of shallow ground water. However, the maximum depth at which it 

was detected in terrestrial field dissipation studies was 15 cm. The mobility of the degradate IM 

1-4, which is a residue of concern for aquatic organisms, is similar to the mobility of the parent. 

Kd values ranged from 0.38 to 21.9 L/kg-soil in four soils and one sediment and Koc values 

ranged from 153 – 1842 L/kg-organic carbon. The mean Koc for IM 1-4 (775 L/kg-organic 

carbon) was slightly higher than the mean Koc for the parent (227 L/kg-organic carbon). 

Therefore, the sorption coefficients for the parent will be used in modeling. 

6.6. Monitoring Data 

The following databases and sources were searched on May 4, 2012 for monitoring information 

on acetamiprid: 

 The United States Environmental Protection Agency (USEPA) STORET Database 

(http://www.epa.gov/storet/dbtop.html) 

 The United States Geological Survey (USGS) National Water-Quality Assessment 

(NAWQA) Program Data Warehouse 

(http://infotrek.er.usgs.gov/traverse/f?p=NAWQA:HOME:1405517206944567) 

 The USGS National Stream Quality Accounting Network (NASQAN) program 

(http://water.usgs.gov/nasqan/) 

No monitoring data are available as none of the databases reported looking for acetamiprid. 

7. Clean Water Act 

Acetamiprid is not identified as a cause of impairment for any water bodies listed as impaired 

under section 303(d) of the Clean Water Act, based on information provided at 

http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_group_id=88

5. In addition, no Total Maximum Daily Loads (TMDL) have been developed for acetamiprid, 

based on information provided at 

http://iaspub.epa.gov/tmdl_waters10/attains_nation.tmdl_pollutant_detail?p_pollutant_group_id

=885&p_pollutant_group_name=PESTICIDES. More information on impaired water bodies and 

TMDLs can be found at http://www.epa.gov/owow/tmdl/. 

The Agency invites submission of water quality data for this pesticide. To the extent possible, 

data should conform to the quality standards in Appendix A of the OPP Standard Operating 

Procedure: Inclusion of Impaired Water Body and Other Water Quality Data in OPP’s 

 

16 Classification is based on the FAO classification system (USEPA, 2010a) 
41 

Registration Review Risk Assessment and Management Process (see: 

http://www.epa.gov/oppfead1/cb/ppdc/2006/november06/session1-sop.pdf), in order to ensure 

they can be used quantitatively or qualitatively in pesticide risk assessments. 

8. Receptors 

Consistent with the process described in the Overview Document (USEPA, 2004b), the risk 

assessment for acetamiprid will rely on a surrogate species approach. Toxicological data 

generated from surrogate test species, which are intended to be representative of broad groups of 

organisms, are used to extrapolate potential effects on a variety of species (receptors) within 

these groups. Categories of organisms evaluated include: fish, arthropods (insects, crustaceans), 

mollusks, birds, mammals, aquatic vascular and nonvascular plants, and terrestrial plants. 

Acute and chronic toxicity data from studies submitted by the pesticide registrant, along with 

studies available in the open literature, will be used to evaluate the potential direct and indirect 

effects of acetamiprid on aquatic and terrestrial receptors. This includes toxicity of the technical 

grade active ingredient, degradates, and formulated products (e.g. “six-pack” acute toxicity 

studies). Open literature studies are identified using EPA’s publically available ECOTOX 

database (USEPA, 2009a)17, which employs a literature search engine for locating chemical 

toxicity data for aquatic life, terrestrial plants, and wildlife. The evaluation of both data sources 

may also provide insight into the direct and indirect effects of acetamiprid usage on biotic 

communities from loss of sensitive species and from changes in community structure or function. 

The most sensitive endpoint for each group of organisms is used in risk assessment. Assessment 

endpoints include direct toxic effects on the survival, reproduction, and growth of terrestrial and 

aquatic life, as well as indirect effects, such as reduction in prey base and/or modification of 

habitat. A brief summary of the aquatic and terrestrial toxicity data available for acetamiprid and 

its degradates is provided in Sections 8.1 and 8.2, respectively. A more complete summary of 

the available data is presented in Appendix B. In addition, a summary of ecological incidents 

associated with acetamiprid is provided in Section 8.3. Additional information on degradate 

toxicity is discussed in Section 9. 

Toxicity to fish and aquatic invertebrates is categorized using the system shown in Table 8-1

(USEPA, 2004a). Toxicity to terrestrial fauna (birds and mammals) is categorized using the 

system shown in Table 8-2. Toxicity categories for plants have not been defined. 

Table 8-1. Categories of Acute Toxicity for Aquatic Animals 

LC50 (ppm) Toxicity Category 

< 0.1 Very highly toxic 

> 0.1 - 1 Highly toxic 

> 1 - 10 Moderately toxic 

> 10 - 100 Slightly toxic 

 

17 http://cfpub.epa.gov/ecotox/ 
42 

> 100 Practically nontoxic 

Table 8-2. Categories of Acute Toxicity for Terrestrial Animals 

LD50 (mg/kg) LC50 (ppm) Toxicity Category 

<10 <50 Very highly toxic 

10-50 50-500 Highly toxic 

51-500 501 - 1000 Moderately toxic 

501-2000 1001 - 5000 Slightly toxic 

>2000 >5000 Practically nontoxic 

8.1. Effects to Aquatic Organisms 

The most sensitive aquatic toxicity endpoints resulting from acetamiprid (parent) and degradate 

exposure based on registrant-submitted studies are provided in Tables 8-3 and 8-4, respectively. 

As long as additional information is not submitted or available in the open literature, these 

endpoints will be used to calculate RQ values for acetamiprid. A single aquatic toxicity study 

(Beketov and Liess, 2008) was available in ECOTOX as of April 20, 2012; this study will be 

evaluated for utility in risk assessment during the Registration Review process. 

8.1.A. Acetamiprid (Parent) 

(a) Fish and Aquatic-Phase Amphibians 

Two acute toxicity studies of the effect of acetamiprid on freshwater fish species were submitted. 

The 96-hr LC50 values are greater than 100 and 119 mg ai/L for the rainbow trout (Oncorhynchus 

mykiss; MRID 44651864) and bluegill sunfish (Lepomis macrochirus; MRID 44651863), 

respectively. Acetamiprid is therefore classified as practically non-toxic to freshwater fish on an 

acute exposure basis. Sublethal effects were noted in both studies. In rainbow trout, darkened 

body pigmentation, swollen abdomen, and loss of equilibrium were reported at the three highest 

concentrations (50, 70, 100 mg ai/L). In bluegill sunfish, darkened body pigmentation was 

observed in all fish at all treatments (11.8, 20.0, 35.4, 65.0, 119.3 mg ai/L). Unless more 

sensitive data is found in the open literature, the acute toxicity estimate for trout will be used to 

assess potential acute risk to freshwater fish (and aquatic-phase amphibians for which they serve 

as surrogates) during risk assessment. 

In the only acute estuarine/marine fish study involving acetamiprid, the 96-hr LC50 for the 

sheepshead minnow (Cyprinodon variegatus; MRID 44988411) is 100 mg ai/L, and lethargy was 

observed in all surviving fish at 90 mg ai/L. Acetamiprid is classified as slightly toxic to 

estuarine/marine fish on an acute exposure basis. Unless more sensitive data is found in the open 

literature, the acute toxicity estimate for the sheepshead minnow will be used to assess potential 

acute risk to estuarine/marine fish during risk assessment. 
43 

A 35-day early life stage toxicity study (MRID 44651872) of fathead minnows (Pimephales 

promelas) was submitted to evaluate the chronic effects of acetamiprid on freshwater fish. The 

lowest observed adverse effect concentration (LOAEC) for the study is 38.4 mg ai/L based on 

both decreased survival and growth (measured by weight). The no-observed-adverse-effect 

concentration (NOAEC) is 19.2 mg ai/L, and this will be used to estimate potential chronic risk 

to freshwater fish (and aquatic-phase amphibians for which they serve as surrogates) during risk 

assessment. 

No chronic toxicity data were submitted for estuarine/marine fish. However, given the low acute 

toxicity to both freshwater and estuarine/marine fish and the low likelihood of adverse chronic 

effects to freshwater fish identified in previous assessments, the need for chronic toxicity data for 

estuarine/marine fish is considered low. 

(b) Aquatic Invertebrates 

The non-biting midge (Chironomus riparius; MRID 45916201) is the most sensitive freshwater 

aquatic invertebrate species in which acetamiprid was tested. The 48-hr LC50 for the midge is 

0.021 mg ai/L, and acetamiprid is therefore considered very highly toxic to freshwater 

invertebrates on an acute exposure basis. Acetamiprid is approximately three orders of 

magnitude more toxic to chironomids than to the freshwater cladoceran Daphnia magna (48-hr 

LC50 =50 mg ai/L; MRID 44651866) on an acute exposure basis. Therefore, the chironomid 

endpoint value will represent freshwater invertebrates during risk assessment. 

Acetamiprid is also very highly toxic to mysid shrimp (Americamysis bahia; MRID 44651869), 

an estuarine/marine invertebrate, on an acute exposure basis (48-hr LC50 =0.066 mg ai/L). 

Sublethal effects (e.g., lethargy) were observed among all the surviving mysids exposed to the 

0.064 and 0.110 mg ai/L treatment levels and in at least one individual at all concentrations 

except the lowest (0.013 mg ai/L). 

Chronic toxicity data for acetamiprid is available for D. magna (MRID 44651871). Survival was 

reduced in this species by 57%, compared to controls, at the highest test concentration (74 mg 

ai/L). Significant reductions in length (8%), weight (24%), and mean number of offspring (50%) 

were observed at 9 mg ai/L, resulting in a NOAEC of 5 mg ai/L based on reduced growth and 

reproduction. However, since acetamiprid is approximately three orders of magnitude more 

toxic to chironomids (LC50 =0.021 mg ai/L) than to daphnids (LC50 =50 mg ai/L) on an acute 

exposure basis, the available chronic endpoint for D. magna may not adequately represent 

chronic toxicity to more sensitive freshwater invertebrates. Therefore, an acute-to-chronic ratio 

(ACR) approach is used for this assessment. Since the acute daphnid endpoint is 50 mg ai/L and 

the chronic NOAEC is 5 mg ai/L, the ACR is for this species is 10. Applying the ACR to the 

chironomid acute toxicity endpoint results in an estimated chronic toxicity endpoint of 0.0021 

mg ai/L. This ACR value will be used to calculate chronic RQ values for freshwater 

invertebrates unless more sensitive data is identified in the open literature. 

A chronic study with acetamiprid (MRID 44651873) was also carried out on mysid shrimp as a 

representative of estuarine/marine invertebrates. Reduction in male dry body weight was the 
44 

most sensitive endpoint, yielding a NOAEC of 0.0025 mg ai/L and a LOAEC of 0.0047 mg ai/L. 

The percent reduction in male dry weight ranged from 11 to 36% in test levels that significantly 

differed from the dilution control. 

Although acetamiprid is registered for use as an insecticide, the high sensitivity of amphipods 

(acute; see Appendix B for endpoint data) and mysid shrimp (acute and chronic) to the chemical 

suggests that there is the potential for concern to a variety of aquatic invertebrates, not just 

insects. Characterization of the taxonomic breadth and magnitude of this potential risk will be 

addressed during the upcoming risk assessment. 

(c) Aquatic Plants 

Tier 1 toxicity testing with aquatic plants indicates that acetamiprid is not toxic at the 

concentrations tested (Table 8-3). Exposure to acetamiprid did not significantly affect growth in 

the single aquatic vascular plant species (Lemna gibba, 14-day test) and four nonvascular plants 

species at limit concentrations tested ranging from 1.0 to 1.3 mg ai/L. 

Table 8-3. Most Sensitive Aquatic Toxicity Endpoints for Acetamiprid

Species Measured 

Effect Duration Endpoint Toxicity Value mg ai/L 

Test 

Substance 

% ai 

MRID 

(Study 

Classification) 

Freshwater Fish 

Oncorhynchus 

mykiss 

(Rainbow Trout) 

Mortality 96 hours LC50

>100*

(Practically 

non-toxic)

>99% 44651864 

(Acceptable) 

Pimephales 

promelas 

(Fathead Minnow) 

Embryo and 

larval survival, 

larval growth 

(wet-weight 

and length) 

35 days NOAEC 

LOAEC 

19.2 

38.4 100% 44651872 

(Supplemental) 

Freshwater Invertebrates 

Chironomus 

riparius 

(Non-biting Midge) 

Mortality 48 hours LC50

0.021

(Very highly 

toxic) 

99.3 45916201 

(Supplemental) 

Calculated 

Value -- NOAEC 0.0021† 

Acute-tochronic 

Ratio 

-- 

Estuarine/Marine Fish 

Cyprinodon 

variegatus 

(Sheepshead 

minnow) 

Mortality 96 hours LC50

100

(Slightly toxic) 99.9% 44988411 (Acceptable) 

Estuarine/Marine Invertebrates 

Americamysis bahia 

(Mysid shrimp)

Mortality 96 hours LC50

0.066

(Very highly 

toxic) 

99.9% 44651869 

(Acceptable) 

Reduced body 

weight in 

males 

28 days NOAEC 

LOAEC 

0.0025

0.0047 99.9% 44651873 

(Acceptable) 
45 

Species Measured 

Effect Duration Endpoint Toxicity Value mg ai/L 

Test 

Substance 

% ai 

MRID 

(Study 

Classification) 

Aquatic Vascular Plants 

Lemna gibba 

(duckweed) Frond number 14 days EC50 >1.0* 99.9% 44988415 

NOAEC 1.0 (Acceptable) 

Aquatic Non-Vascular Plants 

Navicula 

pelliculosa

(Freshwater diatom)

Cell density 5 days 

EC50 >1.1* 

99.9% 44988417 

NOAEC 1.1 (Acceptable) 

Skeletonema 

costatum 

(Marine diatom)

Cell density 5 days 

EC50 >1.0* 

99.9% 44988418 

NOAEC 1.0 (Acceptable) 

* Non-definitive study endpoint; cannot be used to calculate RQs. 

†

 Endpoint is estimated using the ACR of 10 calculated for D. magna (acute LC50 of 50 mg ai/L divided by chronic 

NOAEC of 5 mg ai/L = 10); applying ACR to the midge acute 48-hr LC50 of 0.021 mg ai/L results in estimate 

NOAEC of 0.0021 mg ai/L; unless additional data becomes available, this value will be used to estimate risk in 

upcoming Registration Review Ecological Risk Assessment. 

8.1.B. Degradate Effects to Aquatic Organisms 

An acute toxicity study of the degradate IM 1-4 on rainbow trout (MRID 44651865) was 

conducted at concentrations ranging from 4.3 to 69.3 mg ai/L (Table 8-4). No mortalities were 

reported except at the 69.3 mg ai/L test level, but this may have been due to buffering problems 

in the test solution, as pH levels ranged from 9.0-9.3. An additional concentration was 

subsequently tested under buffered conditions at 98.1 mg ai/L, and no mortality was observed. 

Sublethal effects, including darkened body pigmentation and surface swimming, were observed 

at concentrations above 4.3 mg ai/L. The 96-hr LC50 is >98.1 mg ai/L, classifying the degradate 

IM 1-4 as either slightly toxic or practically nontoxic to freshwater fish on an acute exposure 

basis. The 96-hr LC50 for the parent in rainbow trout (96-hr LC50>100 mg acetamiprid/L) was 

also non-definitive. 

Acute toxicity to aquatic invertebrates was evaluated for several degradates of acetamiprid. 

Toxicity tests on D. magna with degradates IC-0 (MRID 44988409), IM-1-2 (MRID 44651867), 

and IM 1-4 (MRID 44651868) resulted in 48-hr LC50 values of >95.1, >99.8, and 43.9 mg ai/L, 

respectively, while the D. magna 48-hr LC50 for the parent compound is 50 mg ai/L (MRID 

44651866). This indicates that IM 1-4 has similar toxicity to the parent for freshwater aquatic 

invertebrates. The 48-hr LC50 of IM 1-5 for the non-biting midge (MRID 46255610) is 68 mg 

ai/L as compared to 0.021 mg ai/L for the parent, acetamiprid. 

For estuarine/marine invertebrates, the only acute toxicity test with a degradate was with IM 1-4 

on mysid shrimp (MRID 44651870), resulting in a 96-hr LC50 of 19 mg ai/L, which is two orders 

of magnitude less sensitive than the parent compound endpoint value of 0.066 mg ai/L for the 

same species. 
46 

A single chronic toxicity study with acetamiprid degradates was carried out with the IM 1-5 

degradation product in D. magna (MRID 44651871). Significant reduction in mean number of 

offspring (30%) was observed at 51 mg ai/L, the LOAEC, resulting in a NOAEC of 26 mg ai/L 

based on impaired reproduction. 

Overall, the data suggest that degradation products of acetamiprid have low toxicity to aquatic 

invertebrates, although similar toxicity of IM 1-4 to D. magna relative to the parent compound 

indicates that they may be equally toxic to some aquatic animal taxa. Given this uncertainty, a 

total toxic residues (TTR) approach is recommended for risk assessment for aquatic animals, 

where combined exposure values for parent and IM 1-4 degradate are compared to study 

endpoints for the purpose of estimating risk. An additional rationale for considering IM 1-4 in a 

TTR approach is that many degradates ultimately transform into IM 1-4 and IM 1-4 was 

observed at high levels in both field and lab studies. Identification and discussion of acetamiprid 

degradates that will be considered as residues of concern for risk assessment is provided in the 

portion of the document dealing with stressors or concern (Section 9). 

Table 8-4. Aquatic Toxicity Endpoints for Degradates of Acetamiprid 

Species 

(Degradate) 

Measured 

Effect Duration Endpoint Toxicity Value mg ai/L 

Degradate 

% ai 

MRID 

(Study 

Classification) 

Freshwater Fish 

Oncorhynchus 

mykiss 

(Rainbow Trout) 

Mortality 96 hours LC50

>98.1*

(Slightly to 

practically nontoxic)

IM 1-4 

96.7% 

44651865 

(Acceptable) 

Freshwater Invertebrates 

Daphnia magna 

(Water flea)

Immobility 48 hours EC50

>95.1* 

(Practically 

non-toxic) 

IC-0 

99.7% 

44988409 

(Acceptable) 

Immobility 48 hours EC50

>99.8* 

(Practically 

non-toxic) 

IM 1-2 

99.6% 

44651867 

(Acceptable) 

Immobility 48 hours EC50

43.9 

(Slightly toxic) 

IM 1-4 

98.7% 

44651868 

(Acceptable) 

Chironomus 

riparius 

(Non-biting Midge)

Mortality 48 hours LC50

68 

(Slightly toxic) 

IM 1-5 

98.9% 

46255610 

(Acceptable) 

Daphnia magna 

(Water flea)

Number of 

young per 

female 

21 days NOAEC 

LOAEC 

26 

51 

IM 1-5 

98.9% 

46255609 

(Supplemental) 

Estuarine/Marine Invertebrates 

Americamysis bahia 

(Mysid shrimp) Mortality 96 hours LC50

19 

(Slightly toxic) 

IM 1-4 

99.6% 

44651870 

(Acceptable) 

* Non-definitive study endpoint; cannot be used for risk estimation during risk assessment. 
47 

8.2. Effects to Terrestrial Organisms 

The most sensitive toxicity endpoint values associated with acetamiprid exposure to terrestrial 

organisms are shown in Tables 8-5 and 8-6. These endpoints will be used to calculate RQs for 

acetamiprid. The ECOTOX database was searched on April 20, 2012 for terrestrial organism 

toxicity data, and relevant studies are preliminarily discussed in the sections below. 

8.2.A. Acetamiprid (Parent) Toxicity 

(a) 4.2.1.1. Birds 

Acute oral toxicity studies have been submitted for two avian species: the zebra finch 

(Taeniopygia guttata; MRID 48407701) and the mallard duck (Anas platyrhynchos; MRID 

44651859). The former study was submitted in 2011 in order to represent toxicity to passerine 

birds. Acetamiprid is very highly toxic to zebra finches (14-day LD50 =5.68 mg ai/kg-bw) and 

moderately toxic to mallards (LD50 of 84.4 mg ai/kg-bw) on an acute oral exposure basis. Zebra 

finches are the most sensitive species for acute oral toxicity and their endpoint will be used for 

risk assessment. In both studies, at least one sublethal effect (e.g., ruffled appearance, lethargy, 

loss of coordination) was observed at all doses. 

Subacute dietary toxicity studies were performed on both the mallard duck (MRID 44651861) 

and the northern bobwhite quail (Colinus virginianus; MRID 44651860). The mallard and bobwhite quail studies tested three and two concentrations, respectively. The 5-day dietary LC50

reported in both of these studies was >5000 mg ai/kg-diet since less than 50% mortality was 

observed at all concentrations tested. Both studies reported mortalities and sublethal effects at 

one or more test levels. The lowest concentration where no effects were observed was 200 mg 

ai/kg-diet in the mallard study based on reduced survival, behavioral effects, and decreased food 

consumption and 1000 mg ai/kg-bw in the quail study based on reduced survival and decreased 

food consumption. According to OPPTS 850.2200 guidance, a minimum of five test substance 

concentrations should be used during definitive avian dietary toxicity tests. Moreover, when 

mortalities are observed at one or more concentration levels, as is the case in both of these 

studies, a full definitive study (i.e., with five test concentrations) is recommended according to 

EFED’s non-definitive endpoint guidance policy. Since a definitive endpoint was not established 

in either of these studies, they will not be used to calculate RQs but may be used to characterize 

effects to birds based on sub-acute dietary exposure. It should also be noted that an avian dietary 

toxicity study (MRID48844901) of acetamiprid in the zebra finch has recently been submitted 

and is currently under review. 

Chronic toxicity to birds was initially evaluated in the form of two reproduction studies using 

mallards (MRID 44988408) and northern bobwhite quail (MRID 44988407). However, there 

were uncertainties regarding major endpoints in both studies resulting in submission of two new 

studies in the same two species (MRIDs 46369201, 46555601). In the more recent mallard 

study, reduced male body weight was the most sensitive endpoint and was observed at all 

treatment levels (treatment range: 60.2 to 461 mg ai/kg-diet). Number of eggs laid, eggs set, 

viable embryos, and hatchling body weights were all affected at the 461 mg ai/kg-diet level. In 
48 

the more recent bobwhite quail study, the most sensitive endpoint was reduced hatchling body 

weight, which was observed at all test concentrations except the lowest, resulting in NOAEC and 

LOAEC values of 89.7 and 184 mg ai/kg-diet, respectively. Number of eggs laid, eggs set, 

viable embryos, and hatchling body weights were all reduced relative to controls at the 771 mg 

ai/kg-diet level. Since the mallard duck showed higher sensitivity than the bobwhite quail but 

yielded a non-definitive endpoint, chronic risk will be assumed for birds (as well as reptiles and 

terrestrial-phase amphibians) during risk assessment unless an additional study is submitted. 

(b) Mammals 

Studies evaluating the toxicity of acetamiprid to mammals were reviewed by the OPP Health 

Effects Division (HED); based on those reviews, acetamiprid is classified as highly toxic to 

mammals on an acute oral exposure basis. During initial testing in male and female rats (Rattus 

norvegicus) at acetamiprid doses ranging from 100 to 510 mg/kg-bw, more than half of the 

females died at all test levels except the lowest (i.e., 100 mg/kg-bw) (MRID 44651833). 

Therefore, additional testing was carried out, with female rats only, at doses ranging from 80 to 

160 mg/kg-bw. Based on the additional testing, the 14-day LD50 for female rats was 146 mg 

ai/kg-bw. Clinical signs of toxicity included crouching, tremors, low sensitivity, lateral position, 

prone position, salivation, and ataxia. All surviving animals returned to normal appearance and 

behavior by day 2 of the study. 

Consistent results were reported in rats for a two-year chronic feeding study (MRIDs 44988429 

and 45245304), a two-generation reproduction study (MRID 44988430), and a 13-week 

subchronic study (MRID 44651843) with acetamiprid. Reduction in growth, as measured by 

body weight, weight gain, and food consumption, was observed at test concentrations of 400-800 

mg ai/kg-diet and greater; whereas test concentrations of 160-280 mg ai/kg-diet caused no 

significant adverse effects. In addition to growth endpoints, reproductive effects (e.g., pup 

weight, litter size, viability) were also observed at 280 mg ai/kg-diet in the two-generation 

reproduction study (MRID 44988430). The NOAEC (160 mg/kg diet) that will be used for risk 

assessment will be based on the growth endpoints from the 2-year chronic feeding study. 

(c) Terrestrial Invertebrates 

An acute contact toxicity test with technical acetamiprid was conducted on young adult 

European honeybees (MRID 44651874). In this study, percent mortality was 40, 66.7, 46.7, 

63.3, and 60% for the 6.25, 12.5, 25, 50, and 100 μg ai/bee test groups, respectively. The LD50

for the contact study was reported as 8.1 μg/bee. However, there is uncertainty in this LD50

value since no clear dose-response relationship was apparent. Since percent mortality was 

66.7% at 12.5 μg ai/bee, the median mortality dose is considered to be below this value (i.e., 

<12.5) suggesting that acetamiprid should be considered moderately toxic to honeybees on an 

acute contact exposure basis (Atkins et al., 1976). In the ECOTOX database, Iwasa et al. (2004) 

report an acute contact 24-hr LD50 of 7.07 μg ai/bee. Although this endpoint was based on 

nominal concentrations and the exposure period was half that of a typical guideline acute contact 

study (i.e., 48 hrs), it does generally support the registrant-submitted study finding that 

acetamiprid is moderately toxic to honeybees on a contact exposure basis. A full open-literature 
49 

review of Iwasa et al. (2004) will be conducted during the upcoming risk assessment. 

An acute oral study was also carried out in honeybees (MRID 44651874), as well as oral and 

contact studies in bumble bees (Bombus terrestris; MRID 45932503), but endpoint values were 

greater than those from the guideline honeybee acute contact toxicity study. 

EPA currently relies on a tiered approach for evaluating the potential effects of pesticides on 

honeybees. If an acute contact toxicity test (Tier 1) results in a 48-hr LC50 value less than 11 μg 

ai/bee, then honeybee toxicity of residues on foliage studies (Guideline 850.3030)18 can be 

required (Tier 2). However, if the 48-hr LC50 is less than 11 μg ai/bee and there are data 

indicating potential effects to honeybee colonies, then field testing of pollinators (Tier 3) may be 

requested consistent with (Guideline 850.3040)19. 

Since the reported 48-hr LD50 of the honeybee acute contact toxicity study was <12.5 μg/bee, a 

toxicity of residues on foliage study was submitted (MRID 44651875) but was deemed 

unacceptable due to low recovery of acetamiprid on treated foliage. A second residues on foliage 

toxicity study was submitted, but has not yet been reviewed by EFED (MRID 45346901). Two 

semi-field studies conducted to evaluate the possible effect of acetamiprid on honeybee behavior 

were also submitted (MRIDs 45932504; 45932505), and were classified as supplemental20. Both 

studies used tents to expose honeybees via contact with forage and/or overspray, and applications 

rates were equivalent to 0.15 and 0.09 lbs ai/A, which is in line with single application rates for 

many registered and proposed crop uses. Mortality, flight frequency, and foraging behavior were 

evaluated relative to a control and a known toxic standard. No significant effects on any 

endpoints were observed in either study from acetamiprid treatments. 

Several open literature studies of acetamiprid effects on honeybees are available for acetamiprid. 

These studies will be thoroughly reviewed as part of the upcoming Registration Review risk 

assessment. 

Table 8-5. Most Sensitive Terrestrial Animal Toxicity Endpoints for Acetamiprid 

Species Measured effect Endpoint Test 

Duration 

Toxicity Value 

(Acute Toxicity 

Category) 

Test 

Substance 

% ai 

MRID 

(Study 

Classification)

Birds

Taeniopygia

guttata

(Zebra finch) 

Mortality LD50 14 days 5.68 mg ai/kg-bw 

(Very highly toxic) 99.9% 48407701 

(Acceptable) 

 

18 USEPA. 1996. Ecological Effects Test Guidelines. OPPTS 850.3030. Honeybee Toxicity of Residues on 

Foliage. EPA 712–C–96–148. April 1996. 

http://www.epa.gov/ocspp/pubs/frs/publications/OPPTS_Harmonized/850_Ecological_Effects_Test_Guidelines/Dra

fts/850-3030.pdf 

19 USEPA. 1996. Ecological Effects Test Guidelines. OPPTS 850.3040. Field Testing for Pollinators. EPA 712–C–

96–150. April 1996. 

http://www.epa.gov/ocspp/pubs/frs/publications/OPPTS_Harmonized/850_Ecological_Effects_Test_Guidelines/Dra

fts/850-3040.pdf 

20 Note: non-guideline studies cannot be rated “acceptable” since there are no guideline standards 
50 

Species Measured effect Endpoint Test 

Duration 

Toxicity Value 

(Acute Toxicity 

Category) 

Test 

Substance 

% ai 

MRID 

(Study 

Classification)

Bobwhite quail 

(Colinus 

virginianus) 

Mortality LC50 5 days 

>5,000 mg/kg-diet* 

(Practically nontoxic) >99% 44651860 

(Supplemental) 

Anas 

platyrhynchos 

(mallard duck)

Growth (body 

weight; weight 

gain; food 

consumption) 

NOAEC 

LOAEC 22 weeks <60.2 mg ai/kg-diet* 60.2 mg ai/kg-diet 100% 46369201 (Supplemental) 

Mammals

Rattus 

norvegicus 

(laboratory rat) 

Mortality LD50 14 days 

146 mg/kg-bw;

females†

(Highly toxic) 

99.5% 

44651833 

(Acceptable: 

Reviewed by 

HED) 

Growth (female 

body weight; 

female weight 

gain) 

NOAEC 

LOAEC 24 months 

160 mg/kg-diet

(7.1 mg/kg-bw/day) 

400 mg/kg-diet 

Not stated 

in DER 44988429 

Terrestrial Arthropods

Apis mellifera

(Honeybee) Mortality LD50 72 hours 

Acute contact 

<12.5 μg ai/bee 

Acute oral 

>10.21 μg ai/bee 

99% 44651874 

(Acceptable) 

* Non-definitive study endpoint; cannot be used for risk estimation. 

(d) Terrestrial Plants 

The most sensitive terrestrial plant toxicity data are presented in Table 8-6. Seedling emergence 

and vegetative vigor studies (MRID 44988413) were conducted on ten plant species with a test 

substance that was listed as 71.1% acetamiprid as wettable powder. Seedling emergence results 

were classified as supplemental because only shoot length, and not plant weight, was measured 

as an endpoint for growth. Based on shoot length, the most sensitive monocotyledonous 

(monocot) species was onion (Allium cepa; EC25=0.23 lbs ai/A; NOAEC=0.077 lbs ai/A), and 

the most sensitive dicotyledonous (dicot) species was cucumber (Cucumis sativus; EC25=0.16 lbs 

ai/A; NOAEC=0.077 lbs ai/A). The vegetative vigor study was classified as core (i.e., 

acceptable) for all plants except for lettuce (Lactuca sativa), which was classified as 

supplemental because adverse (phytotoxic) effects were observed in control plants. The most 

sensitive monocot and dicot species were ryegrass (Lolium perenne; EC25=0.46 lbs ai/A; 

NOAEC=0.31 lbs ai/A) and lettuce (EC25=0.0087 lbs ai/A; NOAEC=0.0046 lbs ai/A), 

respectively. Since lettuce was particularly sensitive to acetamiprid but the study was classified 

as supplemental, an additional vegetative vigor study was carried out on lettuce alone (MRID 

45921401). The results of this study support the previous finding that lettuce is relatively 

sensitive (EC25=0.0056 lbs ai/A; NOAEC=0.0025 lbs ai/A) compared to other plant species 

tested. Since lettuce serves as a surrogate for broadleaf dicots, potential toxicity to this larger 

group of plants is possible. Two nonguideline studies were also carried out to more closely 

examine the effects of acetamiprid on lettuce. Both studies (MRIDs 46229601 and 46229602) 

reported that the variety of lettuce (i.e., buttercrunch) used in the first two studies, accounted for 
51 

the greater sensitivity of lettuce relative to other species tested, and that other varieties of lettuce 

exhibited reduced sensitivities. 

Table 8-6. Most Sensitive Terrestrial Plant Toxicity Endpoints for Acetamiprid. 

Species 

(Plant 

Group)

Test Substance Study 

Type 

EC25

(lbs ai/A) 

NOAEC 

(lbs ai/A) 

Endpoints 

Affected MRID Study Classification

Onion 

(monocot) 

Wettable powder 

formulation 

(71.1% ai) 

Seedling 

emergence 

0.23 0.077 

Shoot 

length 

44988413 

Supplemental Cucumber 

(dicot) 0.16 0.077 

Perennial 

ryegrass 

(monocot) Vegetative 

vigor 

0.46 0.31 Plant 

weight Acceptable 

Lettuce 

(dicot) 

Wettable powder 

formulation 

(70.04 % ai) 

0.0056 0.0025 Shoot 

length 45921401 Supplemental 

8.2.B. Degradate Toxicity to Terrestrial Organisms 

The only available acute or subacute avian study on an acetamiprid degradate is a subacute 

dietary toxicity study of the compound IM 1-4 with the mallard duck (MRID 44651862) (Table 

8-7). The 5-day dietary LC50 was >5000 mg ai/kg-diet, indicating that similar to the parent 

compound, IM 1-4 is practically non-toxic to mallards on a subacute dietary exposure basis. No 

mortalities were observed at any concentration in this study. 

Acute oral toxicity tests with mammals were conducted on several metabolites and degradation 

products of acetamiprid (MRIDs 44988420, 44988421, 44988422, 44651834, 44651835). 

Results of these tests show that these compounds are considerably less toxic than the parent 

compound, and are classified as slightly toxic or practically nontoxic to mammals on an acute 

oral exposure basis. 

Table 8-7. Available Terrestrial Animal Toxicity Endpoints for Degradates. 

Species Measured effect Endpoint 

Toxicity Value 

(Acute Toxicity 

Category) 

Test 

Substance 

% ai 

MRID 

(Study 

Classification)

Birds

Anas 

platyrhynchos 

(Mallard duck) 

Mortality 5-day 

LC50

>5000 mg ai/kg-diet* 

(Practically nontoxic) IM 1-4 44651862 

(Acceptable) 

Mammals

Laboratory Rat Mortality LD50 1792 mg ai/kg-bw 

(Practically nontoxic) IM-0 44988421 

(Acceptable) 
52 

Species Measured effect Endpoint 

Toxicity Value 

(Acute Toxicity 

Category) 

Test 

Substance 

% ai 

MRID 

(Study 

Classification)

Mortality LD50 >5000 mg ai/kg-bw 

(Practically nontoxic) IC-0 44988420 

(Acceptable) 

Mortality LD50 2176 mg ai/kg-bw 

(Practically nontoxic) 

IM 2-2 

99.9% 

44988422 

(Acceptable) 

Mortality LD50 >5000 mg ai/kg-bw 

(Practically nontoxic) 

IM 1-2 

99.6% 

44651835 

(Acceptable) 

Mortality LD50 1088 mg ai/kg-bw 

(Slightly toxic) 

IM 1-4 

99.6% 

44651834 

(Acceptable) 

* Non-definitive study endpoint; cannot be used for risk estimation. 

†

 Endpoint value will be used for risk estimation 

8.3. Incident Database Review 

Since the time of the last risk assessment of acetamiprid in 2011, four incidents have been 

entered into U.S. EPA’s Ecological Incident Information System (EIIS), which was last checked 

on August 28, 2012. One aquatic incident (I022234-001) took place in 2010 that involved a fire 

in a chemical warehouse containing Assail 70 WP insecticide (TGAI: acetamiprid) as well as an 

unreported list of other pesticides and fertilizers; water used to extinguish the fire resulted in 

runoff into a river that was ultimately linked to a fish kill of 700 to 1000 fish of unknown 

species. Since it is not possible to link any one chemical to this incident, the role of acetamiprid 

has been designated as “possible.” Three incidents have been reported for acetamiprid related to 

honeybees. The first incident (I023702-003) spanned the years 2004-2006 and attributed hive 

population losses of 75-80% to Assail (acetamiprid) or Admire (imidacloprid). However, this 

information was published in the form of a newsletter and insufficient information was provided 

to determine the likelihood that acetamiprid was responsible. Another incident (I024270-001), 

which took place in May, 2012, reported dead bees in 48 colonies while pollination services 

were being provided to an orchard containing apple, apricot, and plum trees. Apparently, Assail 

was not applied until bees were removed from the area. It is unknown which other pesticides 

were applied during the bee kill incident. Based on this information, the role of acetamiprid in 

this incident is considered “unlikely.” The final honeybee incident (I023979-002) took place on 

August 25, 2011 and was submitted in the form of an online news article. The incident occurred 

when a cotton field near the area where bees were being kept was sprayed with Assail 70WP at 

8:30 am. All of the honeybees were reported to have died. This incident occurred 10 days after a 

similar bee kill incident attributed to Lorsban (chlorpyrifos); a 60-80 percent loss of the 

beekeeper’s honeybees were reported to have died across the two incidents. Given that a 

spraying of Assail 70 WP was specifically associated with the bee kill, this incident is classified 

as “highly probable.” 

A total of 60 aggregated incidents have been reported in the Office of Pesticide Programs 
53 

Incident Data System (IDS) as of September 5, 2012. Forty-one (68%) of these incidents 

involved damage to plants, two (3%) incidents were reported for wildlife, and 18 (30%) were 

reported for domestic animals. Incident reports for non-target organisms typically provide 

information only on mortality events and plant damage. Sublethal effects in organisms such as 

abnormal behavior, reduced growth, or impaired reproduction are rarely reported, except for 

phytotoxic effects in terrestrial plants. EPA’s changes in the registrant reporting requirements 

for incidents in 1998 may have further reduced the likelihood of incident reports. Registrants are 

now only required to submit detailed information on “major” fish, wildlife, and plant incidents. 

Minor fish, wildlife, and plant incidents, as well as all other non-target incidents, are generally 

reported in aggregate and are not included in EIIS. During the risk assessment associated with 

Registration Review of acetamiprid, these databases will be checked again and any additional 

incidents will be evaluated to determine if they represent current use patterns of acetamiprid. 

The Avian Incident Monitoring System (AIMS; American Bird Conservancy 2009) was also 

queried on August 28, 2012, and did not list any bird incidents associated with acetamiprid. 

9. Identification of Stressors of Concern 

All major degradates of acetamiprid identified in fate studies have a similar pyridylmethylamine 

backbone as the parent and cannot be eliminated from scrutiny based on structural properties 

alone. Additionally, IM 1-2, IM-1-3, IM 1-4, IM 1-5, and IC-0 are all considered major 

degradates as they were observed with greater than 10% applied radioactivity associated with the 

degradate in some studies. Degradates IM-1-3, IM 1-4, and IM 1-5 were also relatively stable 

with peaks observed at the final sampling interval or high levels observed in studies over many 

days. While IM 1-3 is relatively stable, it was only a major degradate in the hydrolysis study 

(pH 9 at 35o

C and 45oC and biotic metabolism is expected to be its predominant degradation 

pathway. Fate data suggest that exposure to these degradates (especially IM 1-4) could be 

significant compared to exposure to the parent. 

Empirical toxicity data were used to determine whether degradates should be considered a 

residue of concern. Based on empirical toxicity data (Table 9-1), degradates IM 1-2, IM 1-5, IC0, and IM-0 only have one or two established endpoints that can be compared with parent data 

from the same species. In these cases, these degradates appear to be less toxic than the parent. It 

should be noted that of the four degradates listed above, only IM 1-5 has data for any taxon that 

is considered to be highly sensitive to the parent (i.e., chironomids, mysid shrimp). In this case, 

IM 1-5 is several orders of magnitude less sensitive to the non-biting midge than the parent 

compound. None of the above listed degradates have available data for mysid shrimp, which is 

the most sensitive estuarine/marine organism to acetamiprid. There is somewhat more data for 

IM 1-4 compared to the other degradates. IM 1-4 is similarly toxic to daphnids as the parent, but 

is considerably less toxic to mysid shrimp. In fish, it is not possible to make an adequate 

comparison since both acetamiprid and IM 1-4 endpoints are non-definitive. In insects, acute 

toxicity data indicate that the presence of an electron-withdrawing moiety (either a nitro or cyano 

group) is important for insecticidal activity, and the nitro group has been shown to result in 

higher toxicity to honey bees (Iwasa et al., 2004). None of the degradates have the cyano or 
54 

nitro group. The assumption will be made in the assessment that IM 1-4 is a residue of concern 

for all aquatic animals as very limited data are available to evaluate sensitivity across species for 

this degradate; the impact of including IM-1-4 and unextracted residues on quantitation of risk 

values will be explored further during the risk assessment. 

Table 9-1. Comparison of Available Empirical Toxicity Data for Acetamiprid and 

Degradates 

Compound 

Empirical (Measured) Toxicity Endpoints 

Rainbow 

Trout 

96-hr LC50

Daphnid 

48-hr LC50

Mysid 

Shrimp 

96-hr EC50

Non-biting 

Midge 

96-hr LC50

Daphnid 

Chronic 

NOAEC 

Mallard 

Subacute 

Dietary LC50

Rat Acute 

Oral LD50

Units* mg/L mg/L mg/L mg/L mg/L mg/kg-diet mg/kg-bw 

Acetamiprid >100 50 0.066 0.021 5.0 >5000 146 

IM-1-2 -- >99.8 -- -- -- -- 2176 

IM-1-4 >98.1 43.9 19 -- -- >5000 1088 

IM-1-5 -- -- -- 68 25 -- -- 

IC-0 -- >95.1 -- -- -- -- >5000 

IM-0 -- -- -- -- -- -- 1792 

* All units are expressed in terms of the parent or degradate (e.g., mg acetamiprid/L water or mg degradate/L water) 

In an attempt to supplement available empirical toxicity data for acetamiprid transformation 

products, estimated toxicity data for degradates were generated using quantitative structureactivity relationships (QSAR) derived in the program ECOSAR21 (version 1.00). ECOSAR is 

only used to prioritize the need for additional data on degradates, not to derive endpoint values 

for use in estimating risk. ECOSAR estimates were compared to measured toxicity information 

for parent and degradates (Table 9-2; an example ECOSAR output is provided in Appendix C). 

QSAR estimates specific to the parent compound class (i.e., halopyridines) were not accurate 

when compared to measured data. Moreover, ECOSAR estimates for degradates were also not 

accurate compared to the empirical degradate dataset. Therefore, ECOSAR estimates appear to 

be of limited use in predicting degradate toxicity for these degradates. ECOSAR did, however, 

predict increased chronic toxicity of IM-1-4 in daphnids (0.025 mg IM 1-4/L) compared to that 

of the parent (0.097 mg acetamiprid /L) (Table 9-2) when using the aliphatic amine chemical 

class as the basis for analysis. 

Based on the available information, none of the identified degradates appear to be more toxic 

than the parent. There is some evidence that acetamiprid and IM 1-4 may be similarly toxic to 

daphnids; conversely, mysid shrimp are approximately two orders of magnitude more sensitive 

to acetamiprid than to IM-1-4. Based on toxicity results for these two species, the extent of IM 1-

4 toxicity to aquatic animals besides mysid shrimp is uncertain. Therefore, unless additional data 

on toxicity of IM 1-4 to other aquatic animals become available prior to risk assessment, total 

residues of parent plus IM 1-4 will be compared to the most sensitive acute and chronic aquatic 

animal endpoints for the parent or IM 1-4, whichever is more sensitive. In addition, unextracted 

residues will also be included in the TTR exposure calculations since it is uncertain how much of 

these unidentified residues are parent or IM 1-4. No specific additional studies to address 

 

21 http://www.epa.gov/oppt/newchems/tools/21ecosar.htm 
55 

degradate toxicity are recommended at this time. 

Table 9-2. ECOSAR Quantitative Structure-Activity Relationship (QSAR) Toxicity 

Predictions for Acetamiprid and Degradates

Compound 

(compounds class 

used by ECOSAR) 

Estimated Toxicity Endpoint (mg/L) 

96-hr FW 

Fish LC50

48-hr 

Daphnid 

LC50

96-hr EC50

Green Algae 

Fish Chronic 

Value 

Daphnid Chronic 

Value 

ECOSAR TOXICITY PREDICTIONS 

Acetamiprid (Parent) 

Empirical

(Measured) >100 50 >1.3 19.2 5.0 

Halopyridines 0.21 0.73 -- 0.30 0.97 

Neutral SAR 59 36 19 5.5 3.7 

IM 1-2 

Empirical

(Measured) -- >99.8 -- -- -- 

Amides 771 236 1.6 4.6 -- 

Halopyridines 0.225 1.4 -- 8.9 -- 

Neutral SAR 5774 2692 563 570 182 

IM 1-3 

Amides 284 101 1.0 1.7 -- 

Halopyridines 0.19 1.0 -- 3.9 -- 

Neutral SAR 2008 988 248 196 72 

IM 1-4 

Empirical

(Measured) >98.1 43.9 -- -- -- 

Aliphatic Amines 182 14 3.8 2.8 0.025 

Halopyridines 0.15 0.80 -- 3.3 -- 

Neutral SAR 1724 843 208 169 61 

IM 1-5 

Empirical

(Measured) -- -- -- -- 25 

Halopyridines 0.184 1.369 -- 27.067 0.752 

Neutral Organic 28011 11695 1682 2821 673 

IC-0 

Empirical

(Measured) -- >95.1 -- -- -- 

Halopyridines-acid 1.5 6.9 -- 12 1.1 

Neutral SAR 447 238 78 43 20 

IM-0 

Halopyridines 0.13 0.75 -- -- -- 

Benzyl Alcohols 360 194 -- -- -- 

Neutral SAR 1934 934 221 190 67 

Method of Estimating Exposure and Evaluating Risk for Degradates 

To estimate exposure to compounds assumed to have a similar toxicity to the parent (e.g., IM 1-4 

for aquatic organisms), a TTR approach will be used by summing the residues observed in fate 

studies and then estimating degradation rates based on the total summed residues. The TTR 
56 

degradation rates will then be used to estimate exposure in place of degradation rates for the 

parent alone. As stated previously, the residues used to estimate degradation rates to estimate 

exposure for aquatic organisms will be parent, IM-1-4, and unextracted residues. The modeled 

TTR amounts will then be compared to toxicity endpoints for the parent or IM-1-4, whichever is 

more sensitive for each taxon. For human health drinking water, residues of concern are assumed 

to be the parent and unextracted residues and these residues will be combined to calculate 

degradation rates to arrive at a final estimated drinking water concentration (EDWC). 

For terrestrial organisms, only the parent is considered a residue of concern as previously 

identified for human health. Unextracted residues are still considered a residue of concern for 

terrestrial organisms since these residues could consist of the parent compound. However, the TREX program, which is used to model exposure of terrestrial organisms to acetamiprid, does not 

use fate data for modeling, except in the case of foliar dissipation data (which is not available for 

acetamiprid). Therefore, even though a TTR approach (parent plus unextracted residues) is 

relevant for terrestrial vertebrates, it does not influence exposure estimates. For terrestrial 

invertebrates, a standard procedure is not available to estimate exposure at this time, and may be 

addressed further at the time of the risk assessment. For terrestrial plants, the program 

TERRPLANT, which estimates exposure through spray drift and runoff, is also not influenced 

by fate parameters. SCIGROW and PRZM/EXAMS may be used to estimate exposure to 

residues in irrigation water and parent and unextracted residues will be included in the 

degradation rates used to estimate exposure. 

Table 9-3 summarizes the different approaches for assessing risk to degradates for each taxon.

Table 9-3. Summary of Residues of Concern and Methods of Estimating Exposure for 

Different Classes of Organisms 

Taxa Residues of Concern1 Toxicity Assumption/ 

 Exposure Assumption Method of Estimating Exposure 

Aquatic 

Animals Acetamiprid, IM 1-4, 

unextracted residues 

Similar Toxicity 

TTR PRZM/EXAMs 

Aquatic Plants 

Terrestrial 

Vertebrates2

Parent and Unextracted 

Residues 

Similar Toxicity 

TTR 

T-REX , unextracted residues will not 

influence results 

Human 

Drinking 

Water 

Parent and Unextracted 

Residues 

Similar Toxicity 

TTR 

PRZM/EXAMs, unextracted residues will 

influence results 

Terrestrial 

Invertebrates 

Parent and Unextracted 

Residues 

Similar Toxicity 

TTR Exposure not currently estimated 

Terrestrial 

Plants 

Parent and unextracted 

residues 

Similar Toxicity 

TTR 

TERRPLANT, unextracted residues will 

not influence results 

SCIGROW and PRZM/EXAMs for 

irrigation water, unextracted residues will 

influence results 

Abbreviation: TTR= Total toxic residue approach 

1

 Unextracted residues are only relevant residues of concern for terrestrial organisms when exposure is estimated for 

drinking water or for residues in irrigation water. 

2

 Residues included in the TTR approach for these taxa are based on HED analysis of residues of concern for 
57 

humans and analysis of available toxicity data on degradates for birds. 

Mixtures 

Evaluation of pesticide environmental mixtures is beyond the scope of this assessment because 

of the myriad factors that cannot be quantified based on the available data. Those factors include 

identification of other possible co-contaminants and their concentrations, differences in the 

pattern and duration of exposure among contaminants, and the differential effects of other 

physical/chemical characteristics of the receiving waters (e.g. organic matter present in sediment 

and suspended water). Evaluation of factors that could influence additivity/synergism is beyond 

the scope of this assessment and the capabilities of the available data to allow for an evaluation. 

However, it is acknowledged that not considering mixtures could over- or under-estimate risks 

depending on the type of interaction and factors discussed above. The assessment will, however, 

analyze the toxicity of formulated products (including formulations involving more than one 

active ingredient) and will determine whether formulated products are more toxic than the 

technical grade active ingredient data used for assessing both direct and indirect risks. There are 

four registered Section 3 products that contain more than one active ingredient. Three contain 

acetamiprid and bifenthrin and one contains acetamiprid (0.26%) and triticonazole (0.78%). 

Available data on rat oral LD50s for these formulations do not indicate that the formulations are 

more toxic to mammals than the active ingredient alone. Therefore, it is assumed that 

formulation toxicity is similar to the parent toxicity for terrestrial organisms. For aquatic 

organisms, exposure to entire formulations may occur with spray drift into a water body or when 

a product is applied directly to water. Products applied to cranberries may be directly applied to 

water. The only other product that is applied in an agricultural setting that could result in spray 

drift is for the product containing acetamiprid (13%) and bifenthrin (10%) (EPA Reg. No. 8033-

116) that is used on soybean. Additional data on the aquatic toxicity of the product used on 

soybeans and representative typical end-use products used on cranberries are needed. 

10. Ecosystems Potentially At Risk 

The ecosystems at risk are often extensive in scope, and as a result it may not be possible to 

identify specific ecosystems during the development of a baseline risk assessment. However, in 

general terms, terrestrial ecosystems potentially at risk could include the treated field and areas 

immediately adjacent to the treated field 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. 

Aquatic ecosystems potentially at risk include water bodies adjacent to, or downstream from, the 

treated field and might include impounded bodies such as ponds, lakes and reservoirs, or flowing 

waterways such as streams or rivers. For uses in coastal areas, aquatic habitat also includes 

marine ecosystems, including estuaries. 

11. Assessment Endpoints 

Assessment endpoints are defined as "explicit expressions of the actual environmental value that 
58 

is to be protected." Selection of the assessment endpoints is based on valued entities (e.g., fish, 

birds), the ecosystems potentially at risk (e.g., water bodies, riparian vegetation, and upland 

habitats), the migration pathways of acetamiprid (e.g., runoff, drift, etc.), and the routes by which 

ecological receptors are exposed to acetamiprid (e.g., direct contact, etc.). Assessment endpoints 

for acetamiprid include direct adverse effects on the survival, reproduction, and growth of the 

receptors, as well as indirect effects, such as reduction of the prey base or modification of 

habitat. Each assessment endpoint requires one or more "measures of ecological effect," defined 

as changes in the attributes of an assessment endpoint or changes in a surrogate entity or attribute 

in response to exposure to a pesticide. Specific measures of ecological effect are generally 

evaluated based on acute and chronic toxicity information from registrant-submitted guideline 

tests that are performed on a limited number of organisms. Additional ecological effects data 

from the open literature will also be considered. 

12. 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 medium, a point of 

exposure for ecological receptors, and a feasible route of exposure. 

The conceptual model for acetamiprid provides a written description and visual representation of 

the predicted relationships between acetamiprid and degradates, potential routes of exposure, and 

the predicted effects for the assessment endpoint. A conceptual model consists of two major 

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

12.1. Risk Hypothesis 

A risk hypothesis describes the predicted relationship among the stressor, exposure, and 

assessment endpoint response along with the rationale for their selection (USEPA, 2004). For 

assessment of acetamiprid, the risk is stressor-initiated, where the stressor is acetamiprid and a 

major degradate IM-1-4 which was identified in the previous risk assessment as having a similar 

toxicity to that of the parent (USEPA, 2009, D364328). The risk hypothesis for this risk 

assessment is provided below: 

Given the uses of acetamiprid and its environmental fate properties, there is a likelihood of 

exposure to non-target terrestrial and/or aquatic organisms. When used in accordance with the 

label, acetamiprid results in potential adverse effects upon the survival, growth, and 

reproduction of non-target terrestrial and aquatic organisms. Based on previous risk 

assessments there are potential direct risks to birds, mammals, freshwater invertebrates, 

estuarine/marine invertebrates, and terrestrial dicotyledonous plants. 
59 

12.2. Conceptual Diagram 

The conceptual model depicts the potential pathways for ecological risk associated with 

acetamiprid use on a variety of use sites. The conceptual model provides an overview of the 

expected exposure routes for terrestrial and aquatic organisms. In assessments, determinations 

are made on whether direct and indirect effects are likely to occur and on whether habitat 

modification may occur. The potential for habitat modification is determined based on primary 

constituent elements (PCEs) (as defined in 50 CFR 414.12(b)) for listed species. Although the 

conceptual models for direct/indirect effects and modification of designated critical habitat 

(PCE)s are shown on the same diagrams, the potential for direct/indirect effects and modification 

of PCEs will be evaluated separately in the assessment. 

The potential exposure pathways and effects of acetamiprid on aquatic environments are 

depicted in Figure 12-1 and for terrestrial environments in Figure 12-2. Figure 12-3 depicts 

exposure from drinking water and inhalation to terrestrial vertebrates and invertebrates. 

Stressors of concern for aquatic animals and plants include parent acetamiprid, IM-1-4, and 

unextracted residues. Stressors of concern for terrestrial animals and terrestrial plants include 

acetamiprid alone. Unextracted residues are also included in the exposure assessment to 

terrestrial organisms when applicable (e.g., when estimating exposure to residues in irrigation 

water for terrestrial plants). Solid arrows depict the most likely routes of exposure and effects; 

dashed lines depict potential routes of exposure that are not considered likely for acetamiprid. 

Applications to individual trees can result in absorption and translocation of acetamiprid from 

the site of application throughout the tree. Birds, mammals, and terrestrial invertebrates may be 

exposed through ingestion of leaves, seeds, pollen, or other edible portions of the tree. These 

exposure pathways are depicted in the conceptual model in Figure 12-4, along with the receptors 

of concern and the potential attribute changes in the receptors due to exposures of acetamiprid. 

Acetamiprid will enter the environment via direct application to terrestrial environments. It may 

move off site via spray drift, runoff, and leaching. Acetamiprid is considered non-volatile from 

dry non-adsorbing surfaces, water, and soil. Additionally, the Screening Tool for Inhalation Risk 

(STIR) version 1.0 (November 23, 2010) indicates that exposure via inhalation is not likely to be 

a risk concern for birds and mammals (Appendix E). These results combined with the estimated 

atmospheric half-life of less than two days indicate that long-range transport in the vapor phase 

is not an exposure pathway of concern. Additionally, the KOA, KOW, and BCF suggest that 

acetamiprid is not likely to bioconcentrate or bioaccumulate in aquatic or terrestrial organisms. 

Organic-carbon normalized sorption coefficient (KOC) values range from 157 to 300 L/kg-OC

indicating that acetamiprid is classified as moderately mobile under the FAO mobility 

classification system. The Screening Imbibition Program (SIP) version 1.0, August 19, 2010 

identifies that acetamiprid has the potential to be present in drinking water at high enough 

concentrations to result in a risk concern (Appendix E). This is a highly conservative evaluation 

as SIP assumes that concentrations in drinking water could be at the level of solubility. 

Acetamiprid may be applied as a flowable, as a gel, or in bait stations. Spray drift is only 

expected to result in significant exposure with broadcast applications (both aerial and ground 

boom spray) of liquids. Spray drift is assumed to be negligible for applications of liquids with a 
60 

hand held sprayer. When acetamiprid is placed into a bait station, runoff into the aquatic 

environment will likely be negligible; however, consumption of bait by non-target insects and 

terrestrial vertebrates may still occur. Aquatic exposure to residues injected into trees will be 

assumed to be minimal/negligible based on a communication with the technical registrant that 

acetamiprid is only injected into high value trees in residential areas. Finally, when acetamiprid 

is applied underground as for some of the termiticide uses, leaching to ground water may occur 

while spray drift and runoff are not likely to occur. 

*Spray drift is not expected to be a significant pathway of exposure for applications of granular materials, seed 

treatments, and for applications of liquids with a hand held sprayer. 

**PCE stands for primary constituent elements and are used to determine whether habitat modification may occur.

Figure 12-1. Conceptual model depicting stressors, exposure pathways, and potential 

effects to aquatic organisms and their habitat from the use of acetamiprid 
61 

*Spray drift is not expected to be a significant pathway of exposure for applications of granular materials, seed 

treatments, or applications of liquids with a handheld sprayer. See Figure 12-3 for drinking water and inhalation 

exposure pathways for terrestrial vertebrates and ingestion of residues in dew by terrestrial invertebrates. 

**PCE stands for primary constituent elements and are used to determine whether habitat modification may occur.

Figure 12-2. Conceptual model depicting stressors, generic exposure pathways, and 

potential effects to terrestrial organisms (terrestrial plants, terrestrial invertebrates, and 

dietary routes of exposure for terrestrial vertebrates) and their habitat from the use of 

acetamiprid 
62 

*Spray drift is not expected to be a significant pathway of exposure for applications of granular materials, seed 

treatments, or applications of liquids with hand held sprayers. 

**PCE stands for primary constituent elements and are used to determine whether habitat modification may occur. 

Figure 12-3. Conceptual model depicting stressors, drinking water and inhalation 

exposure pathways, and potential effects to terrestrial animals from the use of acetamiprid 
63 

 

Figure 12-4. Conceptual model depicting stressors, exposure pathways, and potential 

effects to aquatic and terrestrial organisms from applications of acetamiprid to individual 

trees. 

13. Analysis Plan 

In order to address the risk hypothesis, the potential for adverse effects on the environment is 

estimated. The use, environmental fate, and ecological effects of acetamiprid are characterized 

and integrated to assess the risks. This is accomplished using a risk quotient (ratio of exposure 

concentration to effects concentration) approach. Although risk is often defined as the likelihood 

and magnitude of adverse ecological effects, the risk quotient-based approach does not provide a 

quantitative estimate of likelihood and/or magnitude of an adverse effect. However, as outlined 

in the Overview Document (USEPA, 2004b), the likelihood of adverse effects to individual 

organisms from particular uses of acetamiprid is estimated using the probit dose-response slope 

and either the level of concern (discussed below) or actual calculated risk quotient value. 

This analysis plan will be revisited and may be revised depending upon the information 

Stressor 

Source

Receptors 

Attribute 

Change 

Acetamiprid applied directly to tree 

Direct 

application 

Individual organisms 

Reduced survival 

Reduced growth 

Reduced reproduction 

Terrestrial food items (fruit, 

seeds, foliage, pollen) 

Mammals 

Exposure 

Media 

Direct Contact/ 

Ingestion Ingestion

Ingestion 

Translocation/uptake 

Terrestrial Birds 

insects 

Aquatic 

Organisms 

Runoff 
64 

submitted by the public in response to the opening of the Registration Review docket for 

acetamiprid. 

13.1. Measures of Exposure 

In order to estimate risks of acetamiprid exposure in aquatic and terrestrial environments, all 

exposure modeling and resulting risk conclusions will be based on current label information on 

the maximum application rates and will be estimated for each use of acetamiprid. Measures of 

exposure are based on aquatic and terrestrial models that predict EECs of acetamiprid. 

13.1.A. Exposure in the Aquatic Environment 

Concentrations of acetamiprid and associated residues (IM-1-4 and unextracted residues) in 

surface waters (EECs) will be estimated using PRZM (Pesticide Root Zone Model version 

3.12.2; May 12, 2005) and EXAMS (Exposure Analysis Modeling System version 2.98.04.06; 

April 25, 2005) (Burns, 2000; Carsel et al., 1997). The PRZM model simulates pesticide 

movement from and transformation on an agricultural field following application. The EXAMS 

model simulates resulting concentrations in a receiving water body. The PRZM and EXAMS 

models and their user manuals may be downloaded from the EPA Water Models web-page 

(USEPA, 2011b). Percent Cropped Area (PCA) adjustment factors are used to account for the 

maximum fractional area within a watershed that may be planted with a modeled crop, and are 

used to modify human health drinking water concentrations predicted by PRZM and EXAMS 

(Echeverria et al., 2012). Acetamiprid has uses in agricultural, commercial, and residential uses 

sites; therefore, a PCA of 1.0 will be used. 

EFED is currently exploring methods to assess urban and residential uses on a national basis. At 

the present time, EFED considers the use of the impervious scenario (a Pesticide Root Zone 

Model (PRZM) modeling scenario) as the most suitable available modeling approach for 

impervious runoff. The PRZM impervious scenario may be used in the tier II coupled aquatic 

models PRZM/EXAMS along with a residential or other suitable scenario such as rights-of-way 

(ROW) to obtain EECs. The conceptual model for the residential scenario integrates 

simultaneous modeling of the individual use scenario with an impervious scenario. This 

approach assumes that no watershed is completely covered by either the 1⁄4 acre lot (the basis for 

the residential scenario) or undeveloped land (the basis for the ROW scenario) for residential and 

ROW use patterns; therefore, differential amounts of runoff will occur within the watershed. 

The impervious scenario was developed to represent the paved areas within a watershed not 

including roads, parking lots, sidewalks, and buildings outside the 1⁄4 acre lot (the 1⁄4 acre lot 

scenario accounts for impervious surfaces such as buildings within the represented area). By 

modeling a separate scenario for impervious surfaces, it is also possible to estimate that amount 

of exposure that could occur when the pesticide is oversprayed onto this surface. Using two 

scenarios in tandem requires post-processing of the modeled output in order to derive a weighted 

EEC that represents the contribution of both the pervious (i.e., residential and ROW scenarios) 

and the impervious surfaces. Exposure from both scenarios can also be weighted and 

aggregated. The daily time series from each model run from the times series file 
65 

(NAME_TS.out) generated from the PRZM graphical user interface (PE5.pl) residential and 

impervious surface scenarios are combined using EXCEL. The time series data are weighted 

based on percentage of impervious surface, the percentage of the pervious surface treated, and an 

adjusted time series is created. Rolling averages for the relevant durations of exposure (e.g., 21 

day and 60 day averages) are calculated, and the relevant one-in-ten year return EEC is generated 

from these distributions. 

Concentrations of acetamiprid and associated residues (IM-1-4 and unextracted residues) in 

ground water will be estimated using EFED's Tier I aquatic model SCIGROW (Screening 

Concentration In Ground Water, version 2.3; 8/8/2003). SCIGROW is a regression model used 

as a screening tool to estimate pesticide concentrations found in ground water used as drinking 

water. The output of SCIGROW represents concentrations that might be expected in shallow 

unconfined aquifers under sandy soils, and therefore represents ground water that is most 

potentially vulnerable to pesticide contamination. The SCIGROW model and user’s manual may 

also be downloaded from the EPA Water Models web-page (USEPA, 2011b). Aerobic soil 

metabolism may be assumed to be negligible for uses that are applied at depths where microbial 

activity is minimal. 

The exposure assessment for house perimeter treatment required a modification in the standard 

modeling approach to account for the lack of uniform pesticide application in a small watershed 

such as yard, housing development, etc. The recommended perimeter treatment requires a 10 feet 

treated area around the perimeter of the house and allows for treatment of 3 feet up the side of 

the building. A treated area factor was estimated using a housing density of four 2000 ft2

 houses 

per acre. Each house has a perimeter of 180 ft and treated area of 2,340 ft2 (180 ft × 13 ft). The 

estimated treated area per acre is then 9,360 ft2 which results in an estimated 21% of an acre 

(9,360ft2

/43,560ft2/acre). The application rate may be assumed to be 21% of the actual for the 

perimeter treatment scenario. 

In addition to modeling estimates, available monitoring data will be evaluated. Monitoring data 

will include those collected/reported by states as well as other federal departments/agencies (e.g., 

USGS National Water Quality Assessment; http://water.usgs.gov/nawqa). 

A downstream dilution model (under development) may be used to identify areas downstream 

from a use area that may have EECs high enough to result in a risk concern. This analysis will 

be used to define the potential area of effects for endangered species. 

13.1.B. Exposure to Terrestrial Animals via Residues on Food Items 

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, 10/09/2008) (USEPA, 2008a). 

This model incorporates the Kenaga nomograph, as modified by Fletcher et al. (1994), which is 

based on a large set of field residue data. The upper-limit values from the nomograph represent 

the upper bound of residue values from actual field measurements (Hoerger and Kenaga, 1972). 

The Fletcher et al. (1994) modifications to the Kenaga nomograph are based on measured field 

residues from 249 published research papers, including information on 118 species of plants, 121 
66 

pesticides, and 17 chemical classes (Fletcher et al., 1994). Based on these data, T-REX assumes 

a 35-day foliar dissipation half-life in the absence of other data. 

For applications of gels containing acetamiprid, acute exposure and risks to terrestrial wildlife 

are estimated with the conceptual approach and the LD50/ft2 method given in the model T-REX. 

Terrestrial EECs are calculated based on an estimation of loadings of pesticide per unit area 

(expressed in terms of mg ai/ft2

) for a single application (multiple applications are not accounted 

for in this analysis); the available mass of pesticide per square foot is then compared to the acute 

oral dose for toxicity (LD50 values adjusted for body weight and percent body weight consumed) 

to derive risk quotients for birds and/or mammals. 

The T-REX model is used to estimate exposures and risks to avian and mammalian species 

resulting from acetamiprid seed treatment. T-REX approximates acute exposure from seed 

treatment using avian and mammalian Nagy doses (mg ai bw-1 day-1), and also utilizes an 

approach analogous to the LD50/ft2

 analyses done for granular applications. Chronic exposures 

are estimated based on the maximum seed application rate (mg ai/kg seed), which can be 

compared directly to estimated dietary-based chronic dietary toxicity endpoints to estimate risks. 

13.1.C. Exposure to Terrestrial Plants 

EECs for terrestrial plants inhabiting dry and wetland areas are derived using the program 

TERRPLANT (version 1.2.2, 12/26/2006) (USEPA, 2006). This model uses estimates of 

pesticides in runoff and spray drift to calculate EECs. EECs are based upon solubility, 

application rate and minimum incorporation depth. AgDRIFT may also be used to assess 

exposure to spray drift. 

13.1.D. Exposure to Spray Drift 

Two spray drift models, AgDISP and AgDRIFT, are used to assess exposures of aquatic and 

terrestrial organisms to acetamiprid deposited in terrestrial and aquatic habitats by spray drift. 

AgDrift (version 2.01; dated 5/24/2001)(Spray Drift Task Force Spray Software) is the model 

most commonly used to simulate spray drift into terrestrial and aquatic environments. AgDISP 

(version 8.13; dated 12/14/2004) (Teske and Curbishley, 2003) is used when a parameter needs 

to be modeled that is not available in AgDRIFT. Spray drift analysis will be an important part of 

the analysis in defining the potential area of effects for endangered species. 

13.1.E. Exposure to Terrestrial Plants from Residues in Irrigation Water 

Non-target crops may be exposed to contaminated irrigation waters from surface water or 

shallow ground water containing acetamiprid. The potential risks to plants when exposed to 

irrigation water contaminated with acetamiprid will be estimated for both ground water and 

surface water irrigation sources. The EECs for ground water and surface water will be calculated 

using SCIGROW and PRZM/EXAMs, respectively. Comparisons will be made to the most 

sensitive endpoint from the vegetative vigor study assuming that runoff of irrigation water does 

not occur. 
67 

13.1.F. Exposure from Applications to Individual Trees 

There is no currently approved model for estimating potential exposure to organisms from tree 

injection or bark treatment. A screening-level estimate of exposure will be used in the 

assessment to determine whether a more in-depth analysis of this use pattern is needed due to the 

potential for risk to organisms. The method used to estimate exposure in the terrestrial 

environment is discussed in a recently completed assessment in EFED and the screen is based 

on the following assumptions (USEPA, 2010b). The aquatic risk assessment methodology was 

developed for this problem formulation. 

(1) Aquatic Risk Assessment 

a. The total mass of chemical applied to the trees on one acre is assumed to be an 

application rate. PRZM/EXAMs will be used to estimate potential exposure from 

applications to bark of trees. Spray drift will be assumed to be minimal. Aquatic 

exposure due to tree injections will be assumed to be minimal. 

(2) Concentration of chemical in leaves for Terrestrial Risk Assessment 

a. Leaf concentration was estimated by assuming that 100% of the chemical was 

translocated to the leaves. Leaf mass was estimated using allometric equations 

developed for blue oak trees presented by the USDA Forest Service (Karlick and 

McKay, 2002). The following equations are used to evaluate risk to terrestrial 

organisms. 

EEC = total mass of chemical applied / leaf mass on tree. 

Leaf mass (g) = 1.78x2

 – 12.4x – 108.5 

x = tree circumference at breast height (cm) 

Pesticide concentration on leaves was converted to dose by assuming that birds consume 

114% and mammals consume 95% of their body weight daily using the following 

equation: 

 

 Body weight adjusted EEC for residues on leaves mg/kg bw 

= X mg/kg leaf × 1.14 or 0.95 kg leaf/kg-bw 

13.2. Measures of Effect 

Ecological effects data are used as measures of direct and indirect effects to biological receptors. 

Effects data are obtained from registrant-submitted studies or from literature studies identified by 

the ECOTOX database. The acute measures of effect used for animals in this assessment are the 

LD50, LC50 and EC50. LD stands for "Lethal Dose", and LD50 is the amount of a material, given 

all at once, that is estimated to cause the death of 50% of the test organisms. LC stands for 

"Lethal Concentration" and LC50 is the concentration of a chemical that is estimated to kil1 50% 

of the test organisms. EC stands for "Effect Concentration" and the EC50 is the concentration of a 
68 

chemical that is estimated to produce a specific effect in 50% of the test organisms. Endpoints 

for chronic measures of exposure for listed and non-listed animals are the NOAEL/NOAEC. 

NOAEL stands for "No Observed-Adverse-Effect-Level" and refers to the highest tested dose of 

a substance that has been reported to have no harmful (adverse) effects on test organisms. The 

NOAEC (i.e., "No-Observed-Adverse-Effect-Concentration") is the highest test concentration at 

which none of the observed effects were statistical1y different from the control. For non-listed 

plants, only acute exposures are assessed (i.e., EC25 for terrestrial plants and EC50 for aquatic 

plants); for listed plants either the NOAEC or EC05 is used. 

Where available, sublethal effects observed in both registrant-submitted and open literature 

studies wil1 be evaluated qualitatively. Such effects may include behavioral changes (e.g., 

lethargy and changes in coloration). However, quantitative assessments of risks are limited to 

those endpoints that can be directly linked to the Agency's assessment endpoints of impaired 

survival, growth and reproduction. 

In the absence of taxa-specific data, the assessment of risk for direct effects to non-target 

organisms makes the assumption that toxicity of acetamiprid to birds is similar to terrestrialphase amphibians and reptiles. The same assumption is made for fish and aquatic-phase 

amphibians. In the absence of data for either acute or chronic effects, the conservative 

assumption wil1 be to presume that acetamiprid is toxic. 

13.3. Integration of Exposure and Effects 

Risk characterization is the integration of exposure and ecological effects characterizations to 

determine the potential ecological risk from the registered uses of acetamiprid and the likelihood 

of direct and indirect effects to non-target organisms in aquatic and terrestrial habitats. The 

exposure and toxicity (effects) data are integrated in order to evaluate the risks of adverse 

ecological effects on non-target species. For the assessment of acetamiprid, the risk quotient 

(RQ) method is used to compare exposure and measured toxicity values. EECs are divided by 

acute and chronic toxicity values. The resulting RQs are then compared to the Agency's Levels 

of Concern (LOCs) (USEPA, 2004b)(Appendix F). These criteria are used to indicate when 

acetamiprid use, as directed on the labels, has the potential to cause adverse direct or indirect 

effects to non-target organisms. In addition, incident data from the EIIS will be considered as 

part of the risk characterization. 

13.3.A. Deterministic and Probabilistic Assessment Methods 

The quantitative assessment of risk will primarily depend on the deterministic point-estimate 

(RQ) based approach described in the risk assessment. Depending on the extent of refinement 

needed by the risk manager, risk estimates may be further refined using probabilistic tools that 

the Agency has developed. These tools have been reviewed by FIFRA Scientific Advisory 

Panels22 and have been deemed as an appropriate means of refining assessments where 

deterministic approaches have identified risks. Newer tools may be available to assess the routes 

 

22 http://vvww.epa.gov/scipoly/sap/index.htm 
69 

of exposure and will be applied as appropriate in Registration Review. 

13.3.B. Endocrine Disruptor Screening Program 

As required by FIFRA and FFDCA, EPA reviews numerous studies to assess potential adverse 

outcomes from exposure to chemicals. Collectively, these studies include acute, sub-chronic and 

chronic toxicity, including assessments of carcinogenicity, neurotoxicity, developmental, 

reproductive, and general or systemic toxicity. These studies include endpoints which may be 

susceptible to endocrine influence, including effects on endocrine target organ histopathology, 

organ weights, estrus cyclicity, sexual maturation, fertility, pregnancy rates, reproductive loss, 

and sex ratios in offspring. For ecological hazard assessments, EPA evaluates acute tests and 

chronic studies that assess growth, developmental and reproductive effects in different 

taxonomic groups. As part of its most recent registration decision, EPA reviewed these data and 

selected the most sensitive endpoints for relevant risk assessment scenarios from the existing 

hazard database. However, as required by FFDCA section 408(p), acetamiprid is subject to 

endocrine screening as part of the Endocrine Disruptor Screening Program (EDSP). 

EPA has developed the EDSP to determine whether certain substances (including pesticide 

active and other ingredients) may have an effect in humans or wildlife similar to an effect 

produced by a “naturally occurring estrogen, or other such endocrine effects as the Administrator 

may designate.” The EDSP employs a two-tiered approach to making the statutorily required 

determinations. Tier 1 consists of a battery of 11 screening assays to identify the potential of a 

chemical substance to interact with the estrogen, androgen, or thyroid (E, A, or T) hormonal 

systems. Chemicals that go through Tier 1 screening and are found to have the potential to 

interact with E, A, or T hormonal systems will proceed to the next stage of the EDSP where EPA 

will determine which, if any, of the Tier 2 tests are necessary based on the available data. Tier 2 

testing is designed to identify any adverse endocrine-related effects caused by the substance, and 

establish a dose-response relationship between the dose and the E, A, or T effect. 

Under FFDCA section 408(p), the Agency must screen all pesticide chemicals. Between 

October 2009 and February 2010, EPA issued test orders/data call-ins for the first group of 67 

chemicals, which contains 58 pesticide active ingredients and 9 inert ingredients. Acetamiprid is 

not among the group of 58 pesticide active ingredients on the initial list to be screened under the 

EDSP. Accordingly, as part of Registration Review, EPA will issue future EDSP orders/data 

call-ins, requiring the submission of EDSP screening assays for acetamiprid. For further 

information on the status of the EDSP, the policies and procedures, the list of 67 chemicals, 

future lists, the test guidelines and the Tier 1 screening battery, please visit our website.23

13.3.C. Endangered Species Assessment 

Consistent with the Agency’s responsibility under the Endangered Species Act (ESA), the 

Agency will evaluate risks to Federally-listed threatened and/or endangered (listed) species from 

registered uses of acetamiprid. This assessment will be conducted in accordance with the 

 

23 http://www.epa.gov/endo/ 
70 

Overview Document (USEPA, 2004b), provisions of the ESA, and the Services’ Endangered 

Species Consultation Handbook (USFWS/NMFS, 1998). 

The action area is used to identify all listed (threatened and endangered) species and designated 

critical habitat that could be affected by the Federal action. The Federal action is the 

authorization or registration of pesticide use or uses as described on the label(s) of pesticide 

products containing a particular active ingredient. The action area is defined by the Endangered 

Species Act as, “all areas to be affected directly or indirectly by the Federal action and not 

merely the immediate area involved in the action” (50 CFR §402.2). Based on an analysis of the 

Federal action, the action area is defined by the actual and potential use of the pesticide. 

In the case of nationwide ecological risk assessment conducted for acetamiprid under 

Registration Review, the action area will encompass the entire United States and its territories. 

The purpose of defining the action area as the entire US and its territories is to ensure that the 

initial area of consideration encompasses all areas where acetamiprid may be used now and in 

the future, including the potential for off-site transport via spray drift and downstream dilution. 

Additionally, the concept of a nationwide action area takes into account the potential for direct 

and indirect effects and any potential modification to critical habitat based on ecological effect 

measures associated with reduction in survival, growth, and reproduction, as well as the full suite 

of sublethal effects available in the effects literature. It is important to note that the nationwide 

action area does not imply that direct and/or indirect effects and critical habitat modification are 

expected to or are likely to occur over the full extent of the action area, but rather to identify all 

listed species and critical habitat that may potentially be affected by the action. The Agency will 

use more rigorous analysis including consideration of available land cover data, toxicity data, 

and exposure information to determine areas where individual listed species and designated 

critical habitat may be affected or modified via endpoints associated with reduced survival, 

growth, or reproduction. 

13.3.A. Risk Assessment of Pollinators 

The EPA is aware of registrant-submitted studies and other open literature studies regarding the 

potential effects of neonicotinoid insecticides on insect pollinators and specifically on honey 

bees. EPA is also aware of concerns regarding the potential association between the use of 

nitroguanidine-substituted neonicotinoids and honey bee losses characterized as Colony Collapse 

Disorder (CCD) and the broader phenomenon of declining honey bee health globally. While a 

number of factors (e.g., nutrition, habitat loss, disease, parasites, bee management practices, and 

pesticides) have been hypothesized, no single factor has yet to be identified as the “cause” of 

declines. 

As part of the review process, EPA examines the effects of chemicals on bees based on both 

laboratory and when appropriate, field studies to determine whether individual bees and entire 

bee colonies may be affected by the use of a compound and to support risk mitigation decisions. 

EPA is currently revising its process for assessing pesticide risks to bees to reflect advancements 

in the state of the science that underlie bee exposure and effects assessments. Interim guidance 
71 

(USEPA 201124) on factors to consider when evaluating exposure and effects to bees is available 

to ecological risk assessors. In 2012, EPA will present to a FIFRA Scientific Advisory Panel 

(SAP) a proposed process for quantifying risks to honeybees and identifying exposure and effect 

studies needed to inform that process. Based on input from the SAP, EPA will incorporate its 

revised assessment process to quantify risks to bees in a similar manner as that used to evaluate 

risks to other taxa. 

As EPA’s understanding of the science evolves, its need for data and its evaluation of those data 

will evolve as well. Therefore, as with all taxa, EPA reserves the right to require additional data 

it deems necessary to inform its understanding of potential ecological risks and support its 

associated risk management decisions. Additional data requirements for pollinators may extend 

beyond those identified in problem formulations and preliminary work plans written in support 

of the Registration Review process. 

13.3.B. Human Health Drinking Water Assessment 

In order to bring the drinking water assessment up to date with current data, models and 

simulation model guidance, a new drinking water assessment will be conducted to support future 

human health dietary risk assessments of acetamiprid. The drinking water assessment will 

incorporate model estimates of acetamiprid and unextracted residues in surface water and 

groundwater. Concentrations of acetamiprid and unextracted residues in surface waters will be 

estimated using PRZM and EXAMs (see description in Section 13.1.A), and concentrations in 

ground water will be estimated using SCIGROW (see description in Section 13.1.A). 

The drinking water assessment will also include available surface and ground water monitoring 

data with consideration of changes in use patterns that may have occurred. States are encouraged 

to submit monitoring data for review. 

14. Preliminary Identification of Data Gaps 

14.1. Fate 

Several fate studies are needed to better characterize the environmental fate and transport of 

acetamiprid. The studies listed below will decrease the uncertainty in determining the potential 

exposure to the pesticide. EFED recommends the following studies be required: 

 Aerobic Aquatic Metabolism (OPPTS Guideline 835.4300); test substance acetamiprid, 

data needed for one sediment 

 Anaerobic Aquatic Metabolism (OPPTS Guideline 835.4400); test substance acetamiprid, 

data needed for one sediment 

 Column and Aged Column Leaching Study (OPPTS Guideline 835.1240); Parent and 

 

24 USEPA. 2011. Pesticides: Science and Policy. Interim Guidance on Honey Bee Data Requirements. 

http://www.epa.gov/pesticides/science/efed/policy_guidance/team_authors/terrestrial_biology_tech_team/honeybee

_data_interim_guidance.htm 
72 

representative TEP for formulations applied using trenching, rodding, soil injection, and 

soil excavation techniques 

 Aquatic Field Dissipation (OPPTS Guidelines 835.6200); test substance is representative 

end-use product used on cranberries 

 Aerobic Soil Metabolism (OPPTS Guideline 835.4100), Test substance acetamiprid 

additional information on MRIDs 46255603, 44651881, 44699101, 44651879 or identity 

of unextracted residues 

 Aerobic Aquatic Metabolism (OPPTS Guideline 835.4300), Test substance acetamiprid, 

additional information for MRID 44988513 or identity of unextracted residues 

 Anaerobic Aquatic Metabolism (OPPTS Guideline 835.4400), Test substance 

acetamiprid additional information for MRID 44988512 or identity of unextracted 

residues 

 Environmental Chemistry Methods: Water (OPPTS Guideline 850.7100), parent and 

major degradates IM 1-2, IM 1-5, IM 1-4, IM 1-3, and IC-0 

In addition to the above studies, the following studies would provide additional information that 

would reduce uncertainty in the risk assessment or assist the public in monitoring: 

 Terrestrial Field Dissipation (OPPTS Guideline 835.6100); test substance acetamiprid 

Table 14-1 summarizes the fate data requirements for acetamiprid. A rationale discussing the 

need for each study is also provided below. 

Table 14-1. Summary of Submitted Environmental Fate Studies, Study Classifications and 

Data Gaps for Acetamiprid and Its Degradates 

OPPTS 

Guideline

MRID 

Test 

Material

Study 

Classification

Comments on Study 

Classification 

Data 

Gap?

 Are 

additional 

data needed 

for risk 

assessment? 

Comments 

Hydrolysis 

835.2120 

(161-1) 

44651876

Parent Acceptable Values may be used in 

risk assessment.

No No --

44651877 Supplemental

Screening study at 

50oC. Shown to be 

stable.

Aqueous 

Photolysis 

835.2240 

(161-2) 

44988509

Parent Acceptable Values may be used in 

risk assessment

No No -- 44988511 

Parent

Valid --
73 

OPPTS 

Guideline

MRID 

Test 

Material

Study 

Classification

Comments on Study 

Classification 

Data 

Gap?

 Are 

additional 

data needed 

for risk 

assessment? 

Comments 

Soil Photolysis 

835.2410 

(161-3) 

48563501

Parent Supplemental

Unable to calculate 

half-lives due to 

microbial activity 

being higher in dark 

control than in 

irradiated sample.

Yes No

When microbial 

degradation is present it 

is expected to be a more 

important degradation 

pathway than photolysis.

Additional data are not 

expected to impact the 

risk assessment.

Aerobic Soil 

Metabolism 

835.4100 

(162-1) 

46255603

Parent Supplemental

High unextracted 

residues Yes Yes

All of the studies 

contained high levels of 

unextracted residues and 

maximum amounts of 

residues observed may 

be higher than observed. 

In absence of additional 

data, unextracted 

residues will be included 

when estimating halflives for use in aquatic 

modeling.

44651881

Parent Supplemental

44699101

Parent Supplemental

44651880

Parent

Supplemental 

– Not for use 

in modeling

44651879

Parent Acceptable

Anaerobic Soil 

Metabolism 

835.4200 

(162-2) 

48554501

Parent

SupplementalNot for use in 

modeling

Dissolved oxygen 

concentrations were 

1.9 mg/L

Yes No

While data are required 

by 40 CFR Part 

158.1300, additional 

data are not expected to 

impact the risk 

conclusions.

Aerobic Aquatic 

Metabolism 

835.4300 

(162-4) 

44988513

Parent Acceptable

Data only available on 

one sediment. High 

levels of unextracted 

residues.

Yes Yes

For the study available 

on one sediment there 

were significant 

unextracted residues. In 

the absence of additional 

data, unextracted 

residues will be included 

when estimating halflives for use in aquatic 

modeling. If data are 

only available on one 

sediment the estimated 

value will be multiplied 

by three. 
74 

OPPTS 

Guideline

MRID 

Test 

Material

Study 

Classification

Comments on Study 

Classification 

Data 

Gap?

 Are 

additional 

data needed 

for risk 

assessment? 

Comments 

Anaerobic 

Aquatic 

Metabolism 

835.4400 

(162-3) 

44988513

Parent Acceptable

Data only available on 

one sediment. High 

levels of unextracted 

residues.

Yes Yes

For the study available 

on one sediment there 

were significant 

unextracted residues. In 

the absence of additional 

data, unextracted 

residues will be included 

when estimating halflives for use in aquatic 

modeling. If data are 

only available on one 

sediment the estimated 

value will be multiplied 

by three.

Adsorption/ 

Desorption 

835.1230 

(163-1) 

44651883

Parent Acceptable Test material was 

parent No No --

44651885 

IM-1-4 Valid Test material was IM1-4

Leaching and 

Aged Column 

Leaching 

835.1240 

-- --- -- Yes Yes 

Data are needed to 

predict the risk of 

contamination of ground 

water from uses 

involving trenching, 

rodding, soil excavation, 

and subslab injection. 

Terrestrial Field 

Dissipation 

835.6100 

44988514 

Parent Supplemental

IM-1-2 not stable, 

residues in plants not 

measured

Yes No

Additional data are not 

expected to impact the 

risk assessment 

conclusions.

44988515 

Parent Supplemental

IM-1-2 not stable. 

Residues in plants not 

measured

44988625 

Parent Supplemental No storage stability 

data

835.6200 

Aquatic Field 

Dissipation 

-- -- -- Yes Yes 

Acetamiprid may be 

used on cranberries and 

therefore, applied 

directly to water. 

Therefore, data on 

aquatic field dissipation 

of acetamiprid are 

needed. 
75 

OPPTS 

Guideline

MRID 

Test 

Material

Study 

Classification

Comments on Study 

Classification 

Data 

Gap?

 Are 

additional 

data needed 

for risk 

assessment? 

Comments 

Bioconcentration 

Factor 

850.1730 

-- -- -- No No

Not required because 

KOW is < 1000 (40 CFR 

Part 158.630)

Environmental 

Chemistry 

Method: Water 

850.7100 

44988536 

Parent and 

Major 

Degradates

Satisfactory -- No No

An ECM and ILV are 

needed with a limit of 

quantitation (LOQ) for 

the parent below 2.5 

μg/L that may be used in 

monitoring. Available 

methods have an LOQ 

of 0.1 μg/L.1

Environmental 

Chemistry 

Method: Soil 

and sediment 

850.7100 

44988516/4

4988517 

Parent and 

Major 

Degradates

Satisfactory -- No No

Abbreviations: ECM=Environmental Chemistry Method; ILV=independent laboratory Validation 

1

 The LOQ was based on the NOAEC for mysid (NOAEC = 0.0025 mg ai/L) and an LOC of 1 (MRID 44651873). 

14.1.A. Rationales for Requesting Fate Studies 

 Anaerobic Aquatic Metabolism (OPPTS Guideline 835.4400); test substance acetamiprid, 

data needed for one sediment and additional data needed on the identity of unextracted 

residues for MRID 44988513 

 Aerobic Aquatic Metabolism (OPPTS Guideline 835.4300); test substance acetamiprid, 

data needed for one sediment and additional data needed on the identity of unextracted 

residues for MRID 44988513 

 Aerobic Soil Metabolism (OPPTS Guideline 835.4100), Test substance acetamiprid 

additional information on MRIDs 46255603, 44651881, 44699101, 44651879 regarding 

the identity of unextracted residues 

Data on aerobic aquatic and anaerobic aquatic metabolism (OPPTS Guidelines 835.4300 and 

835.4400) in two sediments each are recommended; however, data are only available for each 

type of test in one sediment. This could result in underestimation or overestimation of typical 

half-lives in such media. Because only a single data point (half-life) is available for each of 

these studies, model input half-lives are assumed to equal three times the measured values, in 

keeping with standard EFED procedure (USEPA, 2009b). Having half-lives from additional 

studies would allow estimation of 90th percentile confidence bounds on the mean half-lives for 

use in modeling, which would probably be less conservative. A total toxic residue (including 

parent, IM-1-4, and unextracted residues) approach is used in modeling for the ecological risk 

assessment. Half-life values used in modeling were high (i.e., >1500 days), and as a 
76 

consequence EECs are conservative. These data gaps will also influence the estimated drinking 

water concentrations (EDWCs). 

The identity of unextracted residues is unknown in a number of submitted studies where 

unextracted residues made up greater than 10% of applied radioactivity (<1 to 40%). This 

creates significant uncertainty for the risk assessment. Due to the uncertainty in the identity of 

these residues, in the absence of additional data, it will be assumed that the unidentified residues 

are residues of concern in estimating the half-lives of total residues of concern. It will be 

assumed that unextracted residues have similar toxicity to the parent compound. In a recently 

completed ecological risk assessment, the parent, IM-1-4, and unextracted residue risk quotients 

were up to twice the values of those for the parent and IM-1-4 only (USEPA, 2011a). For the 

drinking water assessment, inclusion of unextracted residues resulted in EDWCs that were 4 to 

35 times the EDWCs based on parent alone (USEPA, 2011, D394234, D394479). If the identity 

of the unextracted residues were known, the degradate profile would likely change. Additional 

studies that make an effort to ensure that all residues that can be extracted from soil and sediment 

are extracted25, and that those residues are identified, could significantly reduce the uncertainty 

resulting from having significant amounts of unextracted and unidentified residues in 

metabolism studies. 

In all fate studies, efforts should be made to extract all residues from soil and sediment. 

 Column and Aged Column Leaching Study (OPPTS Guideline 835.1240) and Aged 

Column Leaching; Parent and representative TEP for formulations used as termiticides 

Acetamiprid may be used to control termites and is applied via trenching, rodding (boring a 

series of relatively evenly spaced holes in the soil adjacent to the structure and back-filling the 

holes with termiticide and soil), sub slab injection, soil excavation, or injected into piping or 

similar systems around buildings. There is a particular concern for leaching of pesticides applied 

under the soil surface as other chemicals have been found at high levels when applied in this 

manner (USEPA, 1999). The pesticide may be applied below levels where microbial activity is 

high, resulting in greater persistence. There is also a concern that the formulation may enhance 

the movement of the pesticide in soils as the entire formulation is applied under the soil surface. 

The environmental risk concern is that the increased mobility may potentially allow acetamiprid 

to reach drinking water wells and in-ground drainage systems such as French drains, which are 

used to drain water away from basement walls, and tile drains, which are used to lower the water 

table in residential and other areas. Both the French and tile drains typically convey water 

through storm-water drainage-ways to water bodies rather than to wastewater treatment facilities. 

In order to better understand the risk of these uses EFED requests column leaching studies be 

conducted on the parent and representative formulations (including a formulation that is applied 

in foam) that are used in this manner. If the formulation indicates that the formulation is more 

mobile than the parent, EFED believes it would be prudent to request a radio-labeled aged soil 

 

25 A reasonable effort to extract all residues would include employing a variety of extraction solvents and testing 

extraction efficiencies for known analytes. Use of acids and bases if they do not alter the chemical of interest may 

also be used. 
77 

column leaching study that determines how fast the formulation components lose their ability to 

enhance acetamiprid mobility and estimates the rate of decay in mobility enhancement. EFED 

envisions such a study consisting of a radio-labeled aged soil column leaching study using 

acetamiprid formulation aged for different lengths of time (for example, 0 months, 1 month, 3 

months, 6 months, and 1 year). If such a study is performed, EFED recommends that 

acetamiprid and acetamiprid degradates be quantified. It would also be recommended that 

multiple soil types varying in organic matter content be studied including a loamy sand and a silt 

loam or sandy loam. Ideally, the studies would be conducted on soils where 

adsorption/desorption data for the parent were also available and the soils were shown to be 

vulnerable soils. 

 Aquatic Field Dissipation (OPPTS Guidelines 835.6200); test substance is representative 

end-use product used on cranberries 

Acetamiprid may be used on cranberries and applied directly to water. 40 CFR § 158.1300 

recommends that aquatic field dissipation studies be available when products may be applied 

directly to water or when there is a potential for aquatic exposure. Data from aquatic field 

dissipation studies are needed to get a better understanding of the environmental fate of 

acetamiprid in aquatic systems. In the absence of additional data, EFED will use available data 

to predict the fate of acetamiprid in cranberry bogs. 

14.1.B. Discussion of Additional Fate Data to Reduce Uncertainty or Aid in 

Monitoring 

 Terrestrial Field Dissipation (OPPTS Guideline 835.6100), Test substance acetamiprid 

formulation 

Terrestrial field dissipation studies are only available examining applications of wettable 

powders. Studies conducted using other formulations such as soluble concentrates, emulsifiable 

concentrates, and termiticide formulations would reduce the uncertainty on the effect of the 

formulation on the environmental transport of acetamiprid. This would be particularly helpful 

for termiticide formulations that are directly injected below the soil surface. Additionally, IM 1-

2 was converted to IM 1-4 during storage and IM 1-4 was not stable for two of the studies with 

storage stability data. In a third study, storage stability data were not available. This results in 

uncertainty in the maximum residues of IM 1-2 and IM 1-4 that would occur in the environment. 

This is particularly important as concentrations of IM 1-4 were sometimes higher than 

concentrations of the parent. Additional data to resolve these uncertainties in the terrestrial field 

dissipation results would reduce the uncertainty in the risk assessment. 

 Environmental Chemistry Methods (OPPTS Guideline 850.7100) 

Environmental chemistry methods for parent and degradates using a variety of instruments 

would aid the public in being able to monitor for acetamiprid and its degradates in use areas. 

These methods could be specific to acetamiprid, or multiresidue methods for multiple 
78 

compounds that include acetamiprid and/or its degradates. These methods would add to the 

methods already available for monitoring. 

14.2. Ecological Effects 

Several ecological effects studies on acetamiprid are needed to better assess the potential risk of 

exposure to non-target organisms. Table 14-2 summarizes the data that have been submitted for 

the parent compound and also highlights additional studies that are needed for risk assessment. 

Additional rationale for requesting specific studies is outlined below. 

The following studies are needed to decrease uncertainty in risk estimation and characterization 

of acetamiprid: 

Avian Toxicity

 Avian Reproductive Toxicity Study with Mallard Duck – OCSPP 850.2300 [1 Study] 

An avian chronic reproductive toxicity study (MRID 46369201) yielded a non-definitive 

endpoint. A NOAEC value was not derived in the study and effects were recorded at all 

concentrations tested. Establishment of a NOAEC is essential if the study is to be used in risk 

assessment. Therefore the extent of possible chronic risk to birds cannot be determined until an 

additional avian reproduction study (OCSPP 850.2300) is submitted. EFED reviewed this avian 

reproduction study in August, 2005 and classified it as supplemental since it did not establish a 

NOAEC because statistically significant effects on male body weight gain were observed at all 

treatment levels. EFED issued an additional document in 2012 (D325745) reconfirming that the 

study remains classified as supplemental. Therefore, additional data on avian reproductive 

toxicity in mallard ducks are recommended. 

Aquatic Invertebrate Toxicity

 28-day Chironomid Toxicity Test – Non-guideline [1 Study] 

Based on a search of the European Pesticide Properties Database (PPDB), a 28-day chronic study 

with the non-biting midge (Chironomidae) exists. If this is a registrant-sponsored study, EFED 

would appreciate submission of this study to better assess toxicity to sensitive non-target 

arthropods. Submission of these data could potentially be used to avoid relying on an acute-tochronic ratio for estimating chronic toxicity to chironomids. If this study is not available, a new 

study is not being requested for risk assessment. 

 Freshwater invertebrate, acute toxicity, Daphnia – OCSPP 850.1010 Test Substance 

EPA Registration Number 8033.116 and TEP for products used on cranberries 

40 CFR § 158.630 footnote 9 recommends that acute aquatic toxicity testing data be obtained 

when, “An ingredient in the end-use formulation other than the active ingredient is expected to 
79 

enhance the toxicity of the active ingredient or to cause toxicity to aquatic organisms.” EPA 

Registration Number 8033-116 contains both acetamiprid and bifenthrin, which is toxic to 

aquatic organisms, and may be deposited directly into the aquatic environment via spray drift. 

Submission of these data will allow evaluation of the likelihood of risk to aquatic invertebrates 

exposed to this product via spray drift. Additionally, products with applications to cranberries 

may have direct applications to water. OCSPP 850.1010 on representative typical end-use 

products for these products are recommended. 

Terrestrial Invertebrate Toxicity

 Honeybee Toxicity on Foliage Residue Study – OCSPP 850.3030 [1 Study] 

Based on current Agency policy, an acceptable honeybee foliage residue study (OCSPP 

850.3030) is recommended when the acute contact toxicity to bees is <11 μg/bee, as in the case 

of acetamiprid. A toxicity of residues on foliage study (MRID 44651875) was submitted for 

acetamiprid but was deemed unacceptable. While this study design does not address the systemic 

nature of acetamiprid, it is requested to provide a better understanding of the residual toxicity 

associated with foliar applications. It should be noted that a second foliage residue toxicity study 

was submitted in 2001 (MRID 45346901), but has not yet been reviewed by EFED. 

 Honeybee Larval Toxicity Study – Non-guideline [1 Study] 

Since at least one of the registered uses of acetamiprid is as an ovicide, potential effects to young 

bees could exist. Toxicity studies with acetamiprid have only been submitted for young adult 

bees and do not address possible effects on brood (larvae and pupae) survival. In addition, since 

acetamiprid is a systemic fungicide, it may be transferred to pollen and nectar and subsequently 

brought back to hive where larvae and pupae may be exposed. Honeybee brood studies are not 

currently a data requirement in the U.S., however, a non-guideline honeybee larval toxicity study 

is recommended as a special study (see Appendix F for DCI justification table). 

 Nectar and Pollen Residue Study – Non-guideline [1 Study] 

Acetamiprid is a systemic compound, and there is uncertainty as to the extent that residues may 

translocate to pollen and nectar, where honeybee larvae and pupae may be exposed. However, 

this route of exposure will only be considered a potential concern if acetamiprid exhibits 

significant toxicity to larval bees. Therefore, EFED recommends residue studies of pollen and 

nectar (and other plant products, as appropriate) of pollinator-attractive crops on which the 

compound is registered for use (see Appendix F for DCI justification tables) pending the results 

of the non-guideline larval toxicity test. If the screening-level acute RQ exceeds 0.4 (based on 

larval toxicity data), then the pollen and nectar residue study may be requested. EFED will also 

evaluate the HED magnitude of residue toxicity data to determine whether it can be used to 

supplement or replace studies estimating residues of acetamiprid on plant pollen and nectar. 

 Beneficial Insect Studies – Non-guideline [2 Studies] 
80 

Two beneficial insect studies were identified in the European PPDB: one study with the 

parasitoid aphid (Aphidius rhopalosiphi) and one study with the predatory mite (Typhlodromus 

pyri). Both studies appear to report mortality endpoint data. If these studies were sponsored by 

the registrant, EFED would appreciate that they be submitted in order to characterize effects to 

terrestrial invertebrates. 

Terrestrial Plant Toxicity

 Tier II Seedling Emergence Study – OCSPP 850.4100 [1 Study] 

The Tier II seedling emergence study in terrestrial plants (OCSPP 850.4100; MRID 44988413) 

did not measure plant weight, which is one of the two major endpoints in this type of study, 

resulting in uncertainty regarding the effects of acetamiprid on plant growth. Therefore, an 

additional Tier II plant study should be submitted which includes both plant weight and shoot 

length endpoint data from all 10 recommended species. 

Table 14-2. Summary of Submitted Aquatic and Terrestrial Effects Studies and Data Gaps 

for Parent Acetamiprid. 

Guideline Description—Test Substance MRID(s) Study 

Classification

Are additional 

data needed for 

risk 

assessment? 

Comments 

Avian and Mammalian Testing 

850.2100 Avian acute oral toxicity, 

waterfowl—TGAI 44651859 Acceptable No 

850.2100 Avian acute oral toxicity, 

passerine species—TGAI 48407701 Acceptable No 

850.2200 Avian dietary toxicity, 

waterfowl species—TGAI 44651861 Supplemental No 

Definitive study tested less than 

five concentrations; mortalities 

occurred. But available data 

suggest that dietary toxicity is low.

850.2200 Avian dietary toxicity, upland 

game bird—TGAI 44651860 Supplemental No 

Definitive study tested less than 

five concentrations; mortalities 

occurred. But available data 

suggest that dietary toxicity is low.

850.2300 Avian reproduction, waterfowl 

species—TGAI 46369201 Supplemental Yes 

NOAEC not established due to 

effects on male body weight gain 

at all test levels. 

850.2300 Avian reproduction, upland 

game bird species—TGAI 46555601 Acceptable No 

850.2400 Wild mammal toxicity—TGAI None N/A No 

Not triggered based on ecotoxicity 

data, predicted EECs, fate 

properties, and use pattern criteria.

850.2500 Simulated or actual field 

testing—TEP None N/A No 

Not triggered based on ecotoxicity 

data, predicted EECs, fate 

properties, and use pattern criteria.
81 

Guideline Description—Test Substance MRID(s) Study 

Classification

Are additional 

data needed for 

risk 

assessment? 

Comments 

Aquatic Animal Testing 

850.1010 Freshwater invertebrate, acute 

toxicity, Daphnia—TGAI 44651866 Supplemental No 

Water hardness during test (216-

219 mg/L CaCO3 is higher than 

guideline recommended value of 

180 mg/L) 

850.1010 Freshwater invertebrate, acute 

toxicity, Daphnia—TEP Yes 

Data needed on products that 

could result in spray drift into 

aquatic water bodies that contain 

multiple active ingredients. EPA 

Registration Number 8033-116 is a 

liquid formulation that may be 

applied to soybean by aerial or 

ground spray. Additionally, 

products applied to cranberries 

may be applied directly to water. 

850.1020 Freshwater invertebrate, acute 

toxicity, Amphipod—TGAI 45932501 Supplemental No 

Nonguideline 

Freshwater invertebrate, acute 

toxicity, Non-biting midge 

(Chironomidae)—TGAI 

45916201 Supplemental No 

850.1025 Estuarine/Marine Mollusk acute 

toxicity—TGAI 44988410 Acceptable No 

850.1035 Estuarine/Marine crustacean 

acute toxicity—TGAI 44651869 Acceptable No 

850.1075 Freshwater fish, acute toxicity, 

warm water species—TGAI 44651863 Acceptable No 

850.1075 Freshwater fish, acute toxicity, 

cold water species—TGAI 44651864 Acceptable No 

850.1075 Estuarine/Marine fish acute 

toxicity—TGAI 44988411 Acceptable No 

850.1300 Freshwater invertebrate, 

reproduction test—TGAI 44651871 Acceptable No 

850.1350 Estuarine/marine invertebrate, 

reproduction test—TGAI 44651873 Acceptable No 

Nonguideline 28-day toxicity to non-biting 

midge (Chironomidae)—TGAI None N/A No* 

This study was identified in the 

European Pesticide Properties 

Database. If this is a registrantsponsored study, submission of this 

study to EPA is requested. If this 

study is not available, a new study 

is not being recommended. 

850.1400 Freshwater fish, early life stage 

test—TGAI 44651872 Supplemental No 
82 

Guideline Description—Test Substance MRID(s) Study 

Classification

Are additional 

data needed for 

risk 

assessment? 

Comments 

850.1400 Saltwater fish, early life stage 

test—TGAI None N/A No Test not triggered under 40 CFR §158.630 

850.1500 Freshwater fish life cycle test None N/A No Data requirement triggered 

because 

EEC >0.1 of NOAEC of mysid 

from life cycle tests (EEC = 0.7 

mg/L and NOAEC=19.2 mg ai/L). 

However, EECs and the fish early 

life stage toxicity NOAEC (19.2 

mg/L) are not similar. 

Additionally, NOAECs from early 

life stage and fish full life cycle 

studies on thiacloprid (a 

neonicotinoid with a similar 

structure to acetamiprid) were 

similar; also, the reproductive 

NOAECs and parental NOAECs 

from avian and mammalian studies 

with acetamiprid were similar. 

Weight of evidence suggests that 

this study will not provide any 

critical new information (see 

discussion below). 

850.1500 Estuarine/marine fish life cycle 

test None N/A No 

850.1950 Simulated or actual field testing 

for aquatic organisms None N/A No 

Higher tier testing to address risk 

uncertainties have not been 

identified at this time 

Sediment Testing 

850.1735 Whole sediment 10-d 

freshwater invertebrate—TGAI None N/A No 

Data requirement not triggered: 

Kd <50 

Log KOW <3 

KOC <1,000 

850.1740 

Whole sediment 10-d 

estuarine/marine invertebrate—

TGAI 

None N/A No 

Data requirement not triggered: 

Kd <50 

Log KOW <3 

KOC <1,000 

Agencywide 

guideline 

Whole sediment chronic 

freshwater and/or marine 

invertebrate—TGAI 

None N/A No 

Data requirement not triggered: 

Kd <50 

Log KOW <3 

KOC <1,000 
83 

Guideline Description—Test Substance MRID(s) Study 

Classification

Are additional 

data needed for 

risk 

assessment? 

Comments 

Terrestrial Invertebrates 

850.3020 Honeybee acute contact 

toxicity—TGAI 44651874 Supplemental No 

A definitive LD50 was not 

established due to lack of dose 

response; however, study is 

sufficient as a trigger for 

additional tiered bee studies 

850.3030 Honeybee toxicity of residues 

on foliage—TEP 

44651875 Invalid Yes 

While this study does not address 

the systemic nature of acetamiprid, 

it is recommended to provide a 

better understanding of the 

residual toxicity associated with 

foliar applications. Note: an 

additional foliage residue toxicity 

study was submitted (MRID 

45346901), but has not yet been 

reviewed by EFED 

45346901 Not Reviewed N/A 

Review of this study could change 

the recommendation for additional 

foliage residue toxicity data 

850.3040 Field testing for pollinators None N/A No 

Nonguideline Honeybee semi-field tunnel 

study—TEP 

45932504 

45932505 Supplemental No 

Nonguideline Honeybee larval toxicity 

study—TGAI None N/A Yes 

Recommended since 

acetamiprid is systemic 

and may be 

transferred to pollen and 

nectar and subsequently 

brought back to hive 

Nonguideline Honeybee pollen and nectar 

residue study—TEP None N/A Yes 

Recommended since 

acetamiprid is systemic 

and may be 

transferred to pollen and 

nectar and subsequently 

brought back to hive 

Nonguideline 

Toxicity to beneficial insects – 

parasitoid aphid and predatory 

mite (2 studies) 

None N/A No* 

These studies were identified in 

the European Pesticide Properties 

Database. If they are registrantsponsored studies, their 

submission to EPA is requested. 

However, if these studies are not 

available, new studies are not 

being recommended. 
84 

Guideline Description—Test Substance MRID(s) Study 

Classification

Are additional 

data needed for 

risk 

assessment? 

Comments 

Terrestrial Plants 

850.4100 

Tier II 

Seedling emergence (10 

species) —TGAI 44988413 Supplemental Yes†

Seedling weight was not 

measured. Additional study (with 

10 recommended plant species) 

with seedling weight endpoint is 

recommended.

850.4150 

Tier II 

Vegetative vigor (10 species) —

TGAI 44988413 Acceptable No 

Study was acceptable for all plant 

species tested except for lettuce. 

Additional data have since been 

submitted for lettuce.

850.4150 

Tier II 

Vegetative vigor (10 species) —

TGAI 45921401 Supplemental No This study was submitted to 

supplement MRID 44988413

Aquatic Plants 

850.4400 

Tier I 

and/or II 

Tier II Aquatic plant growth, 

vascular plant — TGAI 44988415 Acceptable No 

If future proposed registrations 

result in surface water EECs 

greater/equal to the highest 

concentration tested in studies, 

additional toxicity testing may be 

recommended. 

850.5400 

Tier I 

and/or II 

Tier II Aquatic Plant, freshwater 

green alga species — TGAI 44988414 Acceptable No 

850.5400 

Tier I 

and/or II 

Tier II Aquatic Plant, freshwater 

diatom—TGAI 44988417 Acceptable No 

850.5400 

Tier I 

and/or II 

Tier I Aquatic Plant, marine 

diatom — TGAI 44988418 Acceptable No 

850.5400 

Tier I 

and/or Tier 

II 

Tier II Aquatic Plant, 

cyanobacterium — TGAI 44988416 Acceptable No 

* Study is being requested only if it has already been performed and is available from the registrant. 

Table 14-3. Summary of Submitted Aquatic and Terrestrial Animal Effects Studies and 

Data Gaps for Degradates of Acetamiprid. 

Guideline Description—Test Substance MRID(s) Study 

Classification

Data 

Gap Comments 

Avian and Mammalian Testing 

850.2200 Avian dietary toxicity, 

waterfowl species—IM-1-4 44651862 Supplemental No 

Aquatic Animal Testing 

850.1010 Freshwater invertebrate, acute 

toxicity, Daphnia—IC-0 44988409 Acceptable No 
85 

Guideline Description—Test Substance MRID(s) Study 

Classification

Data 

Gap Comments 

850.1010 Freshwater invertebrate, acute 

toxicity, Daphnia—IM-1-2 44651867 Acceptable No 

850.1010 Freshwater invertebrate, acute 

toxicity, Daphnia—IM-1-4 44651868 Acceptable No 

Nonguideline 

Freshwater invertebrate, acute 

toxicity, Non-biting midge—

IM-1-5 

46255610 Acceptable No 

850.1035 Estuarine/Marine crustacean 

acute toxicity—IM-1-4 44651870 Acceptable No 

850.1075 Freshwater fish, acute toxicity, 

cold water species—IM-1-4 44651865 Supplemental No 

850.1300 Freshwater invertebrate, 

reproduction test—IM-1-5 46255609 Supplemental No 

* Submission of additional data is recommended. 

The following studies are technically data gaps but are not deemed necessary for risk assessment 

of acetamiprid at this time: 

 Avian Dietary Toxicity Studies – OCSPP 850.2200 

 

Two avian subacute dietary toxicity studies were submitted for acetamiprid (MRID 44651860, 

bobwhite quail; MRID 44651861, mallard duck). Both studies estimated the LC50 to be greater 

than the highest concentration tested (>5,000 mg/kg-diet). However, the bobwhite and mallard 

studies only tested two and three concentrations, respectively. OCSPP 850.2200 guidance states 

that a minimum of five concentrations of the test substance should be used during avian dietary 

toxicity definitive tests. Moreover, mortalities were observed at one or more concentration levels 

in both studies, which triggers full (i.e., five concentrations) definitive tests in accordance with 

EFED’s non-definitive endpoint guidance policy. Additionally, range-finding data were not 

submitted for the bobwhite quail study, which would help support the “greater than” LC50 result. 

The mallard duck study was conducted during two different time periods; initially, two test 

concentrations were evaluated followed by an additional test concentration two months later. 

However, given that the passerine oral toxicity data is at least one order of magnitude lower 

(more sensitive) than the avian sub-acute dietary data, requesting additional dietary studies is not 

likely to change the outcome of the risk assessment. It should also be noted that an avian dietary 

toxicity study (MRID48844901) of acetamiprid in the zebra finch has recently been submitted 

and is currently under review. 
86 

 Freshwater Fish Life Cycle Test – OCSPP 850.1500 

40 CFR § 158.630 recommends that a freshwater fish life cycle test be conducted because EECs 

are greater than 0.1 multiplied by the NOAEC from mysid life cycle test (0.1 x NOAEC of 

Mysid shrimp 2.5 μg ai/L = 0.25; maximum EEC = 0.70 mg/L see Appendix H). However, 

reproductive and parental NOAECs in avian and mammalian reproduction studies were similar, 

suggesting that a reproductive endpoint in fish may also not be more sensitive than the parental 

endpoints. Additionally, when surface water EECs (0.00072 – 0.70 mg/L) generated in this 

problem formulation (Appendix H) and in previous assessments are compare to the fish early 

life stage toxicity endpoint for the fathead minnow (19.2 mg ai/L), it appears unlikely that 

effects to freshwater fish will occur with chronic exposure to acetamiprid at current use rates. In 

addition, NOAEC values from a fish early life-stage study on rainbow trout (NOAEC=0.918; 

MRID 44927829) and a fish full life cycle study on fathead minnows (NOAEC=0.718 mg ai/L; 

MRID 44927904) with another cyano-substituted neonicotinoid, thiacloprid, were similar, 

suggesting that a fish full life cycle with acetamiprid is not likely to yield a substantially lower 

NOAEC than the ELS study. Therefore, based on the weight of evidence, requesting a freshwater 

fish life cycle test is not likely to change the outcome of the risk assessment. 

14.2.A. Testing on Typical End-Use Products (TEP) 

A Typical End-Use Product is defined in the Pesticide Assessment Guidelines Subdivision J 

Hazard Evaluation: Nontarget plants on Part 120-2(1) on Page 18 as “a pesticide product that is 

representative of a major formulation category (e.g., emulsifiable concentrate, granular product, 

wettable powder) and pesticide group (e.g., herbicide, fungicide, insecticide etc.) and contains 

the active ingredient of the applicant’s product.” (Holst and Ellwanger, 1982) Page 5 of these 

guidelines provides additional information on what TEP data should be tested for toxicity testing 

in the following excerpt: 

 “The Agency seeks to avoid imposing a burden of duplicative testing on 

applicants for registration. Therefore, where 40 CFR Part 158 specifies that the 

test substance should be a representative end-use product, testing may be 

performed using the formulation in question (end-use product being registered) or 

similar, yet representative, end-use product. It is not necessary to repeat the test 

using other similar products.” (Holst and Ellwanger, 1982) 

When TEP data are requested, data should be submitted for the different formulation types, e.g., 

wettable powder, emulsifiable concentrate, granular, along with a rationale as to why the TEP is 

representative of other similar end-use products. 

14.3. Additional Information Needed on Specific Labels, Uses, and Formulation 

Types 

Some of the labels do not contain enough information to estimate the exposure for particular uses 

without several assumptions. When such information is not provided, the Agency must rely on 
87 

standard assumptions. Such assumptions may be high-end, so that the Agency does not run the 

risk of underestimating risks. The information in question is discussed briefly below: 

 EPA Registration Number WA110010 

The label for EPA registration number WA110010 allows for control of apple maggots in nonagricultural quarantine and pest free areas (including residential areas) on apples, crabapples, 

pears, ornamental plants and trees, and non-bearing fruit and nut trees. The product is applied to 

give the tree uniform spray coverage of the plant. The label does not have a maximum single 

application rate. It does indicate that the product may be applied every 12 days, up to 4 times a 

year, with a maximum of 0.55 lbs ai/A/year. 

 EPA Registration Number 8033-22 

The label for EPA Registration Number 8033-22 does not have a maximum single application 

rate for any of the uses on ornamental and flowering plants grown outdoors and in greenhouses, 

shadehouses, and lathouses. Use instructions give a number of water soluble packets per gallons. 

The following use restrictions are provided: 

 Do not make more than five applications per year 

 Do not reapply more than once every seven days 

 Do not apply more than 0.55 lbs ai per year 

 EPA Registration Number 8033-21 

EPA Registration Number 8033-21 is a liquid ready-to-use product that may be used on 

ornamentals, houseplants, vegetables, citrus fruits, and pome fruits. Neither a maximum single 

application rate nor a maximum number of applications per crop cycle or per year is provided on 

the label. 

 EPA Registration Number 8033-108 

EPA Registration Number 8033-108 is a product for homeowner use. Use sites include gardens 

and houseplants. No maximum single application rate, maximum number of applications, or 

maximum application rate per year or crop cycle are provided. 

 EPA Registration Number 8033-107 

EPA Registration Number 8033-107 is a homeowner product registered for use on gardens, 

vegetables, pome fruits, grapes and other climbing vine small fruit (except fuzzy kiwifruit), 

tuberous and corm vegetables, stone fruit, cucurbits, tree nuts, edible podded and legume 

vegetables, succulent shelled peas, beans, blueberries and other bush and cane berries, onions, 

bulb vegetables, and houseplants. No maximum single application rate, maximum number of 

applications, or maximum application rate per year or crop cycle are provided. 
88 

 Agricultural Uses 

Many agricultural product labels do not specify maximum number of applications per crop cycle 

or year or maximum application rate per year or crop cycle. A few uses on transplants provide a 

use rate in lbs ai/plant. As a high number of plants may be planted, this results in a very high 

estimated application rate per acre. A maximum single application rate in lbs ai/A or maximum 

number of plants treated per acre is needed to estimate exposure. In the absence of this 

information, EFED will use estimates on the maximum number of plants that may be planted per 

acre to estimate a maximum single application rate for these uses. 

 Uses on Trees 

Labels of two products allow for use of tree injections or basal bark treatments (EPA Reg No. 

8033-94 and 8033-106) on ornamental and non-bearing fruit and nut trees. The use parameters 

on the labels are not well-defined. Use rates for trees are provided only as recommendations on 

these labels. The maximum annual application rate is not specified for any of the uses for trees. 

No maximum single or annual rate is provided for bark treatment. Minimum application 

intervals and the maximum number of applications per year are not specified. In addition, 

applications to individual trees are also not well-defined; a maximum amount of acetamiprid that 

can be applied per diameter of the tree is needed to determine exposure and potential risks 

associated with applications to individual trees. Finally, it would also be helpful define a 

maximum amount of acetamiprid that can be applied to individual trees per acre or info on a 

maximum number of trees that could be treated per acre with various diameter at breast heights 

(DBH). It would also be useful to specify the types of sites for which the product is intended 

(e.g., forest, tree production, residential, etc.). 

 Termiticides, Ant Control, and Control of other Pests 

For termiticide, ant control, and the control of other miscellaneous pests around buildings, 

structures, equipment, paths, wood products, etc., a maximum single application rate per acre, 

maximum number of applications, and maximum application per year should also be provided on 

labels. For mound treatments, in the absence of additional information, EFED will use estimates 

on the maximum number of mounds per acre that may occur to estimate an application rate. For 

perimeter treatments, a maximum distance from the edge of the building that may be treated 

should be provided. In the absence if additional information provided on the labels, EFED will 

make conservative assumptions for these uses. 

 Bait Treatments (Gels) 

Some labels provide an application rate per spot. A maximum single application rate per acre or 

other unit area, maximum number of applications, and maximum application per year should be 

provided on labels. In the absence of this information, EFED will use estimates on the maximum 

number of mounds per acre that may occur in order to estimate an application rate. 
89 

 Seed Treatments 

Acetamiprid may be used to treat mustard, canola, and potato seed pieces. For seed treatment 

uses, the following information is needed: 

 Number of seeds (treated seeds, if encapsulated) per pound 

 Number of treated seeds per acre or pound of treated seed per acre 

 Amount of active ingredient per treated seed or cwt of seed 

 Minimum planting depth 

 Identify where the treatment is for commercial use only or commercial and "on farm" 

treatments can be made 

 Uses on Cranberries 

Acetamiprid may be used on cranberries. The use directions for cranberries are combined with 

use instructions for other berries that do not have a portion of the crop that is flooded. More 

information is needed on the labels describing use of acetamiprid on cranberries because 

cranberries are grown in cranberry bogs and may involve direct applications to water. For uses 

that may involve direct applications to water, it is recommended that the following information 

be included on the label so that exposure may be estimated. 

 The maximum target concentration in water must be specified on the label (specify if 

there is a requirement to test the water body for stratification to calculate the 

application rate) 

 Describe the period of time water must be held before it is released 

 Granular Formulations 

In order to assess the risk to terrestrial organisms exposed to baits or granules not in a container 

or bait station the weight of one granule or number of granules per unit weight for each granular 

formulation would be useful. 

14.4. Other Information Needs 

There is specific information that will assist the Agency in refining the ecological risk 

assessment, including any species-specific effects determinations. The Agency is very much 

interested in obtaining the following information: 

 Confirmation on the following label information 

 Frequency of application, application intervals, and maximum number of 

applications per season 

 Geographic limitations on use 

 Use or potential use distribution (e.g., acreage and geographical distribution of relevant 

crops) 

 Use history 
90 

 Median and 90th percentile reported use rates (lbs. ai/acre) from usage data – national, 

state, and county 

 Application timing (date of first application and application intervals) by crop – national, 

state, and county 

 Sub-county crop location data 

 Directly acquired county-level usage data (not derived from state level data) 

 Maximum reported use rate (lbs. ai/acre) from usage data – county 

 Percent crop treated – county 

 Median and 90th percentile number of applications – county 

 Total pounds per year – county 

 The year the pesticide was last used in the county/sub-county area 

 The years in which the pesticide was applied in the county/sub-county area 

 State or local use restrictions 

 Ecological incidents (non-target plant damage and avian, fish, reptilian, amphibian and 

mammalian mortalities) not already reported to the Agency 

 Monitoring data 

15. References 

15.1. Literature Cited 

AERU. 2012. The FOOTPRINT Pesticide Properties Database. Agriculture & Environment 

Research Unit (AERU). Available at http://sitem.herts.ac.uk/aeru/footprint/ (Accessed 

August 8, 2012). 

Aliouane, Y., El Hassani, A. K., Gary, V., Armengaud, C., Lambin, M., & Gauthier, M. 2009. 

Subchronic exposure of honeybees to sublethal doses of pesticides: effects on behavior. 

Environ Toxicol Chem, 28(1), 113-122. 

Armitage, J. M., & Gobas, F. A. P. C. 2007. A terrestrial food-chain bioaccumulation model for 

POPs. Environmental Science and Technology, 41, 4019-4025. 

Atkins, E., Anderson, L., Kellum, D., & Neuman, K. 1976. Protecting Honey Bees From 

Pesticides. Univ. California, Div. Agric. Sci., Leaflet 2883. 

Beketov, M. A., & Liess, M. 2008. Potential of 11 pesticides to initiate downstream drift of 

stream macroinvertebrates. Arch Environ Contam Toxicol, 55, 247-253. 

Burns, L. A. 2000. Exposure Analysis Modeling System (EXAMS): User Manual and System 

Documentation. Revision G. EPA/600/R-00/81-023. September 2000. Ecosystems 

Research Division. National Exposure Research Laboratory. United States 

Environmental Protection Agency. 
91 

Carsel, R. F., Imhoff, J. C., Hummel, P. R., Cheplick, J. M., & Donigian Jr., J. S. 1997. PRZM-3, 

A Model for Predicting Pesticide and Nitrogen Fate in Crop Root and Unsaturated Soil 

Zones: Users Manual for Release 3.0. Memorandum From to Environmental Research 

Laboratory. Office of Research and Development. United States Environmental 

Protection Agency. 

Echeverria, M., Jones, R. D., Peck, C., Ruhman, M., Shelby, A., Thawley, S., et al. 2012. 

Development and Use of Percent Cropped Area and Percent Turf Area Adjustment 

Factors in Drinking Water Exposure Assessments: 2012 Update. March 16, 2012. 

Environmental Fate and Effects Division. Office of Pesticide Programs. United States 

Environmental Protection Agency. Available at 

http://www.epa.gov/oppefed1/models/water/pca_adjustment_dwa.html (Accessed April 

25, 2012). 

El Hassani, A. K., Dacher, M., Gary, V., Lambin, M., Gauthier, M., & Armengaud, C. 2008. 

Effects of sublethal doses of acetamiprid and thiamethoxam on the behavior of the 

honeybee (Apis mellifera). Arch Environ Contam Toxicol, 54(4), 653-661. 

Fletcher, J. S., Nellessen, J. E., & Pfleeger, T. G. 1994. Literature-Review and Evaluation of the 

Epa Food-Chain (Kenaga) Nomogram, an Instrument for Estimating Pesticide-Residues 

on Plants. Environmental Toxicology and Chemistry, 13(9), 1383-1391. 

Gobas, F. A. P. C., Kelly, B. C., & Arnot, J. A. 2003. Quantitative structure activity 

relationships for predicting the bioaccumulation of POPs in terrestrial food-webs. QSAR 

Comb. Sci, 22, 329-336. 

Hoerger, F., & Kenaga, E. E. 1972. Pesticide Residues on Plants: Correlation of Representative 

Data as a Basis for Estimation of their Magnitude in the Environment. In F. Coulston & 

F. Korte (Eds.), Environmental Quality and Safety: Chemistry, Toxicology, and 

Technology (Vol. 1, pp. 9-28). New York: Academic Press. 

Holst, R. W., & Ellwanger, T. C. 1982. Pesticide Assessment Guidelines. Subdivision J. Hazard 

Evaluation: Nontarget Plants. EPA-540/09-82-020. October 1982. Office of Pesticide 

Programs. Office of Pesticides and Toxic Substances. United States Environmental 

Protection Agency. 

Iwasa, T., Motoyama, N., Ambrose, J. T., & Roe, R. M. 2004. Mechanism for the differential 

toxicity of neonicotinoid insecticides in the honey bee, Apis mellifera. Crop Protection, 

23(5), 371-378. 

Karlick, J. F., & McKay, A. H. 2002. Leaf Area Index, Leaf Mass Density, and Allometric 

Relationships Derived From Harvest of Blue Oaks in a California Oak Savanna. General 
92 

Technical Report PSW-GTR-184. USDA Forest Service. 

Laurino, D., Porporato, M., Patetta, A., & Manino, A. 2011. Toxicity of neonicotinoid 

insecticides to honey bees: laboratory tests. Bulletin of Insectology, 64(1), 107-113. 

Morrica, P., Fidente, P., & Seccia, S. 2005. Liquid chromatographic determination of nine Nmethylcarbamates in drinking water. Biomedical Chromatography, 19(1), 107-110. 

Spray Drift Task Force Spray Software. AgDRIFT (Version 2.01). Available at 

http://www.agdrift.com/AgDRIFt2/DownloadAgDrift2_0.htm 

Sur, R., & Stork, A. 2003. Uptake, translocation and metabolism of imidacloprid in plants. 

Bulletin of Insectology, 56(1), 35-40. 

Teske, M. E., & Curbishley, T. B. 2003. Continuum Dynamics, Inc. AGDISP Version 8.07 User 

Manual. Prepared For United States Department of Agriculture Forest Service. C.D.I. 

Technical Note No. 02-06. June 2003. 

Tomizawa, M., & Casida, J. E. 2005. NEONICOTINOID INSECTICIDE TOXICOLOGY: 

Mechanisms of Selective Action. Annual Review of Pharmacology and Toxicology, 

45(1), 247-268. 

USEPA. 1998. Government Printing Office. Guidelines for Ecological Risk Assessment. 

EPA/630/R-95/002F. United States Environmental Protection Agency (USEPA). Risk 

Assessment Forum. Office of Research and Development. Available at 

http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=12460 (Accessed June 19, 2009). 

USEPA. 1999. Appendix VII. Addendum to the Drinking Water Memorandum to HED. October 

6, 1999. Environmental Fate and Effects Division. Office of Pesticide Programs. . 

USEPA. 2001. Acetamiprid. Results of the HED Metabolism Assessment Review Committee. 

D278652. Memorandum From H. Bietlot, M. Doherty & P. Hurley to Y. Donovan. 

Office of Prevention, Pesticides, ans Toxic Substances. United States Environmental 

Protection Agency. 

CFR. Part 2002. Acetamiprid Pesticide Fact Sheet. Government Printing Office. Washington, 

D.C. 

USEPA. 2002.D270368. EFED's Section 3 Risk Assessment for Acetamiprid. D270368. 

Memorandum From F. N. Mastrota & C. A. Sutton to A. Abramovitch. March 4, 2002. 

Environmental Fate and Effects Division. Office of Chemical Safety and Pollution 
93 

Prevention. United States Environmental Protection Agency. 

USEPA. 2004.D304025. Ecological Risk Assessment for Proposed Use of Acetamiprid on 

Potatoes, Tobacco, and Residential (Outdoor) Use Sites. D304025. Memorandum From 

B. D. Kiernan & C. A. Sutton to A. Abramovitch. August 30, 2004. Environmental Fate 

and Effects Division. Office of Prevention, Pesticides, and Toxic Substances. United 

States Environmental Protection Agency. 

USEPA. 2004a. Overview of the Ecological Risk Assessment Process in the Office of Pesticide 

Programs, United States Environmental Protection Agency (USEPA) (pp. 100). 

Washington, D.C.: Government Printing Office. Available at 

http://www.epa.gov/espp/consultation/ecorisk-overview.pdf (Accessed June 19, 2009). 

USEPA. 2004b. Government Printing Office. Overview of the Ecological Risk Assessment 

Process in the Office of Pesticide Programs. United States Environmental Protection 

Agency (USEPA). Environmental Fate and Effects Division. Office of Pesticide 

Programs. Available at http://www.epa.gov/espp/consultation/ecorisk-overview.pdf

(Accessed June 19, 2009). 

USEPA. 2005.D319610. Acetamiprid New Use (Cucurbits, Stone Fruits, and Tree Nuts): 

Environmental Fate and Effects Risk Assessment. D319610. Memorandum From B. D. 

Kiernan & G. Orrice to A. Abramovitch. July 27, 2005. Environmental Fate and Effects 

Division. Office of Chemical Safety and Pollution Prevention. United States 

Environmental Protection Agency. 

USEPA. 2006. User's Guide: TerrPlant version 1.2.2. Memorandum From to Environmental 

Fate and Effects Division, Office of Pesticide Programs, Office of Chemical Safety and 

Pollution Prevention, United States Environmental Protection Agency. Available at 

http://www.epa.gov/oppefed1/models/terrestrial/terrplant/terrplant_user_guide.html

(Accessed May 13, 2011). 

USEPA. 2008a. User's Guide: T-REX version 1.2.2. Memorandum From to Environmental Fate 

and Effects Division, Office of Pesticide Progams, Office of Chemical Safety and 

Pollution Prevention, United States Environmental Protection Agency. Available at 

http://www.epa.gov/oppefed1/models/terrestrial/trex/t_rex_user_guide.htm (Accessed 

May 13, 2011). 

USEPA. 2008b. White paper on Methods for Assessing Ecological Risks of Pesticides with 

Persistent, Bioaccumulative, and Toxic Characteristics. In Submitted to the FIFRA 

Scientific Advisory Panel for Review and Comment (Ed.), October 7, 2008. Washington, 

D.C. Available at 

http://www.epa.gov/scipoly/SAP/meetings/2008/october/sap_pbt_whitepaper_final_Oct_
94 

7_08d.pdf (Accessed January 27, 2010). 

USEPA. 2009.D364328. Ecological Risk Assessment for the Section 3 New Uses of Acetamiprid 

on Red Clover, Small Fruit, and Climbing Vines (Except Kiwi). D3643528. Memorandum 

From B. D. Kiernan & D. Lieu to J. Chao & J. Hebert. December 10, 2009. 

Environmental Fate and Effects Division. Office of Prevention, Pesticides, and Toxic 

Substances. United States Environmental Protection Agency. 

USEPA. 2009a. ECOTOXicology Database, United States Environmental Protection Agency 

(USEPA). Available at http://cfpub.epa.gov/ecotox/ (Accessed June 19, 2009). 

USEPA. 2009b. Estimation Program Interface (EPI) Suite: United States Environmental 

Protection Agency. Available at http://www.epa.gov/oppt/exposure/pubs/episuite.htm

(Accessed August 24, 2012). 

USEPA. 2009c. SAP Minutes No. 2009-01. A set of Scientific Issues Being Considered by the 

Environmental Protection Agency Regarding: Selected Issues Associated with the Risk 

Assessment Process for Pesticides with Persistent, Bioaccumulative, and Toxic 

Characteristics. October 28-31, 2008., January 29, 2009. Available at 

http://www.epa.gov/scipoly/sap/meetings/2008/102808_mtg.htm (Accessed July 9, 

2009). 

USEPA. 2010a. Guidance for Reporting on the Environmental Fate and Transport of the 

Stressors of Concern in the Problem Formulation for Registration Review, Registration 

Review Risk Assessments, Listed Species Litigation Assessments, New Chemical Risk 

Assessments, and Other Relevant Risk Assessments, January 25, 2010. 

USEPA. 2010b. Section 3 Product Registration For Expansion of Tree Species for Emammectin 

Boenzoate Tree Injection Use to Control Arthropod Pests. DP Barcode 381025. October 

5, 2010. Environmental Fate and Effects Division. Office of Pesticide Programs. United 

States Environmental Protection Agency. 

USEPA. 2011a. Ecological Risk Assessment for the Proposed Section 3 New Use of Acetamiprid 

on a Variety of Agricultural Crops and as Bait Near Animal Areas and Enclosed 

Dumpsters. In D. D389536, D394268, D394270 (Ed.), November 29, 2011. 

USEPA. 2011.D394234, D394479. Tier I Drinking Water Exposure Assessment for the Section 

3 New Use of Acetamiprid on Various Agricultural Crops and as a Scatter Bait to 

Control Insects. D394234 & D394479. October 11, 2011. Environmental Fate and 

Effects Division. Office of Pesticide Programs. United States Environmental Protection 

Agency. 
95 

USEPA. 2011b. U.S EPA Water Models. Memorandum From to Environmental Fate and Effects 

Division, Office of Pesticide Programs, Office of Chemical Safety and Pollution 

Prevention, United States Environmental Protection Agency. Available at 

http://www.epa.gov/oppefed1/models/water/#przm (Accessed May 13, 2011). 

USEPA. 2012. BEAD Chemical Profile for Registration Review: Acetamiprid. Memorandum 

From D. Brassard, R. Prierto & M. Ranville to C. Britton. March 1, 2012. Biological and 

Economic Analysis Division. Office of Pesticide Programs. United States 

Environmental Protection Agency. 

USFWS/NMFS. 1998. Government Printing Office. Endangered Species Consultation 

Handbook: Procedures for Conducting Consultation and Conference Activities Under 

Section 7 of the Endangered Species Act. Final Draft. United States Fish and Wildlife 

Service (USFWS) and National Marine Fisheries Service (NMFS). Available at 

http://www.fws.gov/endangered/consultations/s7hndbk/s7hndbk.htm (Accessed June 19, 

2009). 

USNLM. 2009. TOXNET Toxicology Data Network. United States National Library of 

Medicine (USNLM). Available at http://toxnet.nlm.nih.gov/ (Accessed July 9, 2009). 

15.2. Submitted Studies 

Avian Single Dose Oral Toxicity 

44651859 Johnson, A. (1994) NI-25: Acute Oral Toxicity (LD50) to the Mallard Duck: Lab Project Number: NPS 

62/932516. Unpublished study prepared by Huntingdon Research Centre Ltd. 50 p. 

48407701 Hubbard, P. (2011) Acetamiprid: An Acute Oral Toxicity Study with the Zebra Finch (Taeniopygia 

guttata aka Poephila guttata). Unpublished study performed by Wildlife International, Ltd., Easton, 

Maryland. Laboratory Project ID: 437-119. Study sponsored by Nippon Soda Co., Ltd., Chiyoda-ku, 

Tokyo, Japan. 

Avian Dietary Toxicity 

44651860 Johnson, A. (1994) NI-25: Subacute Dietary Toxicity (LC50) to the Bobwhite Quail: Lab Project 

Number: NPS 59/932525. Unpublished study prepared by Huntingdon Research Centre Ltd. 37 p. 

44651861 Johnson, A. (1994) NI-25: Subacute Dietary Toxicity (LC50) to the Mallard Duck: Lab Project Number: 

NPS 60/942075. Unpublished study prepared by Huntingdon Research Centre Ltd. 40 p. 

44651862 Brewer, L.; Taliaferro, M.; Miller, V. (1998) 5-Day Dietary Toxicity Test with IM-1-4 in the Mallard 

Duck (Anas platyrhynchos): Amended Final Report: Lab Project Number: 019803: EBA-019803. 

Unpublished study prepared by EBA, Inc. 166 p. 

Avian Reproduction 

44988407 Taliaferro, M.; Brewer, L.; Miller, V. (1999) Reproduction Study with Acetamiprid in the Northern 

Bobwhite (Colinus virginianus): Amended Final Report: Lab Project Number: 029604. Unpublished 
96 

study prepared by EBA, Inc. 319 p. 

44988408 Taliaferro, M.; Miller, V. (1999) Reproduction Study with Acetamiprid in the Mallard Duck (Anas 

platyrhynchos): Final Report: Lab Project Number: 29708. Unpublished study prepared by EBA, Inc. 

346 p. 

46369201 Stafford, J. (2004) Acetamiprid (NI-25) - Reproductive Toxicity Test with Mallard Duck (Anas 

platyrhynchos). Project Number: 13798/4105. Unpublished study prepared by Springborn Smithers 

Laboratories. 153 p. 

Acute Toxicity to Freshwater Fish 

44651863 Suteau, P. (1997) Acetamiprid: Acute Toxicity (96 Hours) to Bluegill (Lepomis macrochirus) Under 

Flow-Through Conditions: Amended Report: Lab Project Number: SA 96120: R&D/CRSA/ANL/96-

011. Unpublished study prepared by Rhone-Poulenc Agrochimie. 72 p. 

44651864 Saika, O. (1996) NI-25--Acute Toxicity Study in Rainbow Trout: Lab Project Number: H088. 

Unpublished study prepared by Nippon Soda Co., Ltd. 23 p. 

44651865 McElligott, A. (1998) IM-1-4: Acute Toxicity (96 Hours) to Rainbow Trout (Oncorhynchus mykiss) 

Under Semi-Static Conditions: Lab Project Number: SA 97231: R&D/CRSA/ANL/97-012. Unpublished 

study prepared by Rhone-Poulenc Agro. 82 p. 

Acute Toxicity to Freshwater Invertebrates 

44651866 Saika, O. (1997) NI-25: Acute Toxicity Study in Daphnids: Lab Project Number: H100. Unpublished 

study prepared by Nippon Soda Co., Inc. 22 p. 

44651867 McElligott, A. (1997) IM-1-2: Acute Toxicity (48 Hours) to Daphnids (Daphnia magna) Under SemiStatic Conditions: Lab Project Number: SA 97046: R&D/CRSA/ANL/97-010. Unpublished study 

prepared by Rhone-Poulenc Agrochimie. 67 p. 

44651868 McElligott, A. (1997) IM-1-4: Acute Toxicity (48 Hours) to Daphnids (Daphnia magna) Under SemiStatic Conditions: Lab Project Number: SA 97047: R&D/CRSA/ANL/97-012. Unpublished study 

prepared by Rhone-Poulenc Agrochimie. 67 p. 

44988409 McElligott, A. (1997) IC-0: Acute Toxicity (48 Hours) to Daphnids (Daphnia Magna) Under SemiStatic Conditions: Lab Project Number: SA 97045: RND/CRSA/ANL/97-009. Unpublished study 

prepared by Rhone-Poulenc Agrochimie. 66 p. (OPPTS 830.1010) 

45916201 Putt, A. (2003) Acetamiprid Technical--Acute Toxicity to Midge (Chironomus riparius) Under Static 

Conditions: Lab Project Number: 12681.6104: 012803/ASTM/MIDGE/NIPPON SODA. Unpublished 

study prepared by Springborn Smithers Laboratories. 50 p. 

45932501 Putt, A. (2003) Acetamiprid Technical--Acute Toxicity to Gammarids (Gammarus fasciatus) Under 

Static Conditions: Lab Project Number: 12681.6105: 012803/ASTM/GAMMARIDS/NIPPON SODA. 

Unpublished study prepared by Springborn Smithers Laboratories. 50 p. (OPPTS 850.1020) 

Acute Toxicity to Estuarine/Marine Organisms 

44651869 Putt, A. (1998) Acetamiprid Technical--Acute Toxicity to Mysids (Mysidopsis bahia) Under FlowThrough Conditions: Final Report: Lab Project Number: 97-9-7100: 10566.0697.6424.515: 13529. 

Unpublished study prepared by Springborn Laboratories, Inc. 70 p. 

44651870 Putt, A. (1998) IM-1-4--Acute Toxicity to Mysids (Mysidopsis bahia) Under Static Conditions: Final 

Report: Lab Project Number: 98-3-7276: 10566.0198.6468.510: 110797/FIFRA/515/RHONE-
97 

POULENC. Unpublished study prepared by Springborn Laboratories, Inc. 74 p. 

44988410 Dionne, E. (1999) Acetamiprid Technical--Acute Toxicity to the Eastern Oyster (Crassostrea virginica) 

Under Flow-Through Conditions: Final Report: Lab Project Number: 97-10-7105: 

10566.0697.6426.504: 13528. Unpublished study prepared by Springborn Laboratories, Inc. 71 p. 

44988411 Putt, A. (1998) Acetamiprid Technical--Acute Toxicity to Sheepshead Minnow (Cyprinodon variegatus) 

Under Flow-Through Conditions: Final Report: Lab Project Number: 97-10-7104: 

10566.0697.6425.505: 13527. Unpublished study prepared by Springborn Laboratories, Inc. 69 p. 

Fish Early Life Stage/Aquatic Invertebrate Life Cycle Study 

44651871 Suteau, P. (1997) Acetamiprid: Daphnia Magna Life Cycle (21-Day Static Renewal) Chronic Toxicity 

Study: Lab Project Number: SA 96122: R&D/CRSA/ANL/96-011. Unpublished study prepared by 

Rhone-Poulenc Agrochimie. 80 p. 

44651872 Odin-Feurtet, M. (1997) Acetamiprid: Early Life Stage Toxicity Test to Fathead Minnow (Pimephales 

promelas): Lab Project Number: SA 96123: R&D/CRSA/ANL/96-011. Unpublished study prepared by 

Rhone-Poulenc Agrochimie. 89 p. 

44651873 Sousa, J. (1998) Acetamiprid Technical--Chronic Toxicity to Mysids (Mysidopsis bahia) Under FlowThrough Conditions: Final Report: Lab Project Number: 98-2-7230: 10566.0897.6447.530: 

060396/FIFRA/530. Unpublished study prepared by Springborn Laboratories, Inc. 91 p. 

Acute oral toxicity in rats 

44651821 Douds, D. (1997) An Acute Oral Toxicity Study in Rats with EXP 0667A: Amended Final Report: Lab 

Project Number: 3147.237. Unpublished study prepared by Springborn Laboratories, Inc. 69 p. 

44651827 Douds, D. (1998) An Acute Oral Toxicity Study in Rats with NI-25 Plus Carbaryl RTU: Final Report: 

Lab Project Number: 3147.251. Unpublished study prepared by Springborn Laboratories, Inc. 23 p. 

44651833 Mochizuki, N.; Kanaguchi, Y. (1998) Acetamiprid--Acute Oral Toxicity Study in Rats: Lab Project 

Number: G-0820. Unpublished study prepared by Nippon Soda Co., Ltd. 52 p. 

44651834 Wakefield, A. (1998) IM-1-4: Acute Oral Toxicity Study in Rats: Amended Final Report: Lab Project 

Number: 6840-103: 18981-0-800: 22209. Unpublished study prepared by Covance Laboratories Inc. 36 

p. 

44651835 Mochizuki, N.; Goto, K. (1997) IM-1-2: Acute Oral Toxicity Study in Rats: Lab Project Number: G963. 

Unpublished study prepared by Nippon Soda Co., Ltd. 28 p. 

44988420 Mochizuki, N.; Goto, K. (1997) IC-0: Acute Oral Toxicity Study in Rats: Lab Project Number: G-0941: 

3686. Unpublished study prepared by Nippon Soda Co., Ltd. 26 p. 

44988421 Mochizuki, N.; Goto, K. (1997) IM-0: Acute Oral Toxicity Study in Rats: Lab Project Number: G-0887: 

3662. Unpublished study prepared by Nippon Soda Co., Ltd. 45 p. 

44988422 Mochizuki, N.; Goto, K. (1997) IM-2-1: Acute Oral Toxicity Study in Rats: Lab Project Number: G931: 

3684: 3692. Unpublished study prepared by Nippon Soda Co., Ltd. 45 p. 

Acute dermal toxicity in rabbits or rats 

44651822 Douds, D. (1998) An Acute Dermal Toxicity Study in Rabbits with EXP 80667A: (Acetamiprid 70 WP): 

Final Report: Lab Project Number: 3147.238. Unpublished study prepared by Springborn Laboratories, 

Inc. 31 p. 
98 

44651828 Douds, D. (1998) An Acute Dermal Toxicity Study in Rabbits with NI-25 Plus Carbaryl RTU: Final 

Report: Lab Project Number: 3147.252. Unpublished study prepared by Springborn Laboratories, Inc. 30 

p. 

44651836 Mochizuki, N.; Fuji, Y. (1998) Acetamiprid: Acute Dermal Toxicity Study in Rats: Lab Project Number: 

G-0882. Unpublished study prepared by Nippon Soda Co., Ltd. 26 p. 

44988423 Wakefield, A. (1998) IM-1-4: Acute Dermal Toxicity Study in Rats: Amended Final Report: Lab Project 

Number: 6840-104: 1891-0-810: 22209. Unpublished study prepared by Covance Laboratories, Inc. 39 

p. 

Acute inhalation toxicity in rats 

44651823 Bennick, J. (1997) NI-25 70% WP (EXP 80667A) Acute Inhalation Toxicity Study in Rats: Final 

Report: Lab Project Number: 3606-97. Unpublished study prepared by Stillmeadow, Inc. 20 p. 

44651829 Douds, D. (1998) An Acute Nose Only Inhalation Toxicity Study in Rats with NI-25 Plus Carbaryl 

RTU: Final Report: Lab Project Number: 3147.253. Unpublished study prepared by Springborn 

Laboratories, Inc. 43 p. 

44651837 Jackson, G. (1997) Acetamiprid: Acute (Four-Hour) Inhalation Study in Rats: Lab Project Number: 

NOD 4/970598. Unpublished study prepared by Huntingdon Life Sciences Ltd. 40 p. 

Primary eye irritation in rabbits 

44651824 Douds, D. (1998) A Primary Eye Irritation Study in Rabbits with EXP 80667A (Acetamiprid 70WP): 

Final Report: Lab Project Number: 3147.239. Unpublished study prepared by Springborn Laboratories, 

Inc. 29 p. 

44651830 Douds, D. (1998) A Primary Eye Irritation Study in Rabbits with NI-25 Plus Carbaryl RTU: Final 

Report: Lab Project Number: 3147.254. Unpublished study prepared by Springborn Laboratories, Inc. 28 

p. 

44651838 Mochizuki, N.; Goto, K. (1997) Acetamiprid--Primary Eye Irritation Study in Rabbits: Lab Project 

Number: G-0826: 1609. Unpublished study prepared by Nippon Soda Co., Ltd. 32 p. 

Primary dermal irritation 

44651825 Douds, D. (1997) A Primary Skin Irritation Study in Rabbits with EXP 80667A (Acetamiprid 70WP): 

Final Report: Lab Project Number: 3147.240. Unpublished study prepared by Springborn Laboratories, 

Inc. 29 p. 

44651831 Douds, D. (1998) A Primary Skin Irritation Study in Rabbits with NI-25 Plus Carbaryl RTU: Amended 

Final Report: Lab Project Number: 3147.255. Unpublished study prepared by Springborn Laboratories, 

Inc. 29 p. 

44651839 Mochizuki, N.; Goto, K. (1997) Acetamiprid--Primary Dermal Irritation Study in Rabbits: Lab Project 

Number: G-0827: 1605. Unpublished study prepared by Nippon Soda Co., Ltd. 27 p. 

Dermal sensitization 

44651826 Douds, D. (1997) A Dermal Sensitization Study in Guinea Pigs with EXP 80667A (Acetamiprid 70WP) 

Modified Buehler Design: Final Report: Lab Project Number: 3147.241. Unpublished study prepared by 

Springborn Laboratories, Inc. 44 p. 

44651832 Douds, D. (1998) A Dermal Sensitization Study in Guinea Pigs With NI-25 Plus Carbaryl RTU 
99 

Modified Buehler Design: Final Report: Lab Project Number: 3147.256. Unpublished study prepared by 

Springborn Laboratories, Inc. 43 p. 

44651840 Coleman, D. (1997) Acetamiprid: Skin Sensitisation in the Guinea Pig: Lab Project Number: NOD/088: 

NOD 088/973169/SS. Unpublished study prepared by Huntingdon Life Sciences Ltd. 28 p. 

Acute neurotoxicity screen study in rats 

44651841 Hughes, E. (1997) Acetamiprid: Dose Range Finding Neurotoxicity to Rats by Acute Oral 

Administration (including determination of time to peak effect): Lab Project Number: RNP 510/970145. 

Unpublished study prepared by Huntingdon Life Sciences Ltd. 49 p. 

44651842 Hughes, E. (1997) Acetamiprid: Neurotoxicity to Rats by Acute Oral Administration: Lab Project 

Number: RNP/509: RNP 509/970851. Unpublished study prepared by Huntingdon Life Sciences Ltd. 

252 p. 

45130801 Cunny, H. (2000) Supplemental Statistical Analysis and Historical Background Data for the Report 

Titled: Acetamiprid--Neurotoxicity to Rats by Dietary Administration for 13 Weeks (Huntington Study 

RNP/511 and MRID 44651845): Lab Project Number: RNP/511. Unpublished study prepared by 

Huntingdon Life Sciences. 15 p. 

Subchronic Oral Toxicity: 90-Day Study 

44651843 Nukui, T.; Ikeyama, S. (1997) Acetamiprid--Thirteen-Week Dietary Subchronic Toxicity Study in Rats: 

Lab Project Number: G-0768: 0246. Unpublished study prepared by Nippon Soda Co., Ltd. 376 p. 

44988424 Auletta, C. (1998) A Subchronic (3-Month) Oral Toxicity Study of NI-25 in the Dog via Dietary 

Administration: Final Report: Lab Project Number: 91-3727. Unpublished study prepared by 

Bio/Dynamics, Inc. 259 p. OPPTS 870.3150 

44988425 Nukui, T.; Ikeyama, S. (1997) Acetamiprid*-Thirteen-Week Dietary Subchronic Toxicity Study in 

Mice: Lab Project Number: G-0769: 0249. Unpublished study prepared by Nippon Soda Co., Ltd. 341 p. 

44988426 Ivett, J. (1999) 13-Week Dietary Subchronic Toxicity Study with IM-1-4 in Rats: Final Report: Lab 

Project Number: 6840-102. Unpublished study prepared by Covance Laboratories Inc. 353 p. 

44988427 Nukui, T.; Ikeyama, S. (1997) IM-0--Thirteen-Week Dietary Subchronic Toxicity Study in Rats: Lab 

Project Number: G-0889: 0259. Unpublished study prepared by Nippon Soda Co., Ltd. 265 p. 

45245306 Auletta, C. (1998) A 4-Week Oral Toxicity Study of NI-25 in the Dog via Dietary Administration 

(Acetamiprid Technical): Final Report. Unpublished study prepared by Bio-dynamics, Inc. 142 p. 

21-day dermal-rabbit/rat 

44651844 Trutter, J. (1997) 21-Day Dermal Toxicity Study in Rabbits with Acetamiprid: Final Report: Lab Project 

Number: 6224-236. Unpublished study prepared by Covance Laboratories Inc. 212 p. 

Subchronic Neurotoxicity: 90-Day Study 

44651845 Hughes, E. (1997) Acetamiprid: Neurotoxicity to Rats by Dietary Administration for 13 Weeks: 

Lab Project Number: RNP/511: RNP 511/971179. Unpublished study prepared by Huntingdon 

Life Sciences Ltd. 311 p. 

Chronic Toxicity 
100 

44651846 Auletta, C. (1998) A Chronic (12-Month) Oral Toxicity Study of NI-25 in the Dog via Dietary 

Administration: Final Report: Lab Project Number: 92-3117. Unpublished study prepared by Pharmaco 

LSR, Inc. 475 p. 

44988428 Goldenthal, E. (1999) 18-Month Dietary Oncogenicity Study in Mice: NI-25: Lab Project Number: 449-

016. Unpublished study prepared by MPI Research, Inc. 1488 p. OPPTS 870.4200 

44988429 Hatch, R. (1999) Two Year Dietary Toxicity and Oncogenicity Study in Rats: NI-25: Lab Project 

Number: 449-015. Unpublished study prepared by MPI Research, Inc. 2105 p. OPPTS 870.4200 

45245304 Cunny, H. (2000) Supplemental Historical Background Data for the Acetamiprid Two-Year Study in 

Rats--MRID 44988429. Unpublished study prepared by Aventis CropScience. 62 p. 

45245305 Cunny, H. (2000) Supplemental Historical Background Data for the Acetamiprid 18-Month Study in 

Mice--MRID 44988428. Unpublished study prepared by Aventis CropScience. 30 p. 

45532301 Cunny, H.; Pallen, C.; Bouvier, G. (2001) Biological and Statistical Analysis of Mammary Gland 

Findings in the Chronic Rat Study on Acetamiprid. Unpublished study prepared by Aventis 

CropScience. 28 p. 

45532302 Cunny, H. (2001) Supplemental Historical Control Data for the Chronic Rat Study on Acetamiprid. 

Unpublished study prepared by Aventis CropScience. 36 p. 

Oncogenicity 

44988428 Goldenthal, E. (1999) 18-Month Dietary Oncogenicity Study in Mice: NI-25: Lab Project Number: 449-

016. Unpublished study prepared by MPI Research, Inc. 1488 p. OPPTS 870.4200 

44988429 Hatch, R. (1999) Two Year Dietary Toxicity and Oncogenicity Study in Rats: NI-25: Lab Project 

Number: 449-015. Unpublished study prepared by MPI Research, Inc. 2105 p. OPPTS 870.4200 

45245304 Cunny, H. (2000) Supplemental Historical Background Data for the Acetamiprid Two-Year Study in 

Rats--MRID 44988429. Unpublished study prepared by Aventis CropScience. 62 p. 

45245305 Cunny, H. (2000) Supplemental Historical Background Data for the Acetamiprid 18-Month Study in 

Mice--MRID 44988428. Unpublished study prepared by Aventis CropScience. 30 p. 

45532301 Cunny, H.; Pallen, C.; Bouvier, G. (2001) Biological and Statistical Analysis of Mammary Gland 

Findings in the Chronic Rat Study on Acetamiprid. Unpublished study prepared by Aventis 

CropScience. 28 p. 

45532302 Cunny, H. (2001) Supplemental Historical Control Data for the Chronic Rat Study on Acetamiprid. 

Unpublished study prepared by Aventis CropScience. 36 p. 

Teratogenicity -- 2 Species 

44651847 Nukui, T.; Fujii, Y. (1997) Acetamiprid--Teratogenicity Study in Rats: Lab Project Number: G-0829: 

7071. Unpublished study prepared by Nippon Soda Co., Ltd. 279 p. 

44651848 Nukui, T.; Fujii, Y. (1997) Acetamiprid--Teratogenicity Study in Rabbits: Lab Project Number: 

Amended: G-0830: 7074. Unpublished study prepared by Nippon Soda Co., Ltd. 165 p. 

45245302 Cunny, H. (2000) Litter-Based Incidence of Fetal Observations and Historical Control Data for the 

Study, Acetamiprid-Rat Teratology Study (Laboratory Project G-0829): EPA MRID 44651847: Lab 

Project Number: 958540. Unpublished study prepared by Nippon Soda Co., Ltd. 23 p. 

45245303 Cunny, H. (2000) Litter-Based Incidence of Fetal Observations and Historical Control Data for the 

Study, Acetamiprid--Rat Teratology Study (Laboratory Project G-0830): EPA MRID 44651848. 
101 

Unpublished study prepared by Nippon Soda Co., Ltd. 23 p. 

2-generation repro.-rat 

44988430 Trutter, J. (1999) Two-Generation Reproduction Study with NI-25 in Rats (Reproduction and Fertility 

Effects): Final Report: Lab Project Number: 6840-108. Unpublished study prepared by Covance 

Laboratories, Inc. 1605 p. OPPTS 870.3800 

45245301 Cunny, H. (2000) Mean Pup Weights Per Liter (Male and Females Combined) for the Study, TwoGeneration Reproduction Study with NI-25 Rats (Acetamiprid Technical): EPA MRID 44988430. 

Unpublished study prepared by Covance Laboratories, Inc. 15 p. 

Interaction with Gonadal DNA 

44651849 Kanaguchi, Y. (1997) Acetamiprid--Reverse Mutation Study on Bacteria: Lab Project Number: G-0831: 

9816. Unpublished study prepared by Nippon Soda Co., Ltd. 29 p. 

44651850 Mochizuki, N.; Kanaguchi, Y. (1997) IM-1-2--Reverse Mutation Study on Bacteria: Lab Project 

Number: G-964: G964. Unpublished study prepared by Nippon Soda Co., Ltd. 25 p. 

44651851 Mochizuki, N.; Kanaguchi, Y. (1997) IM-1-4--Reverse Mutation Study on Bacteria: Lab Project 

Number: G-940: G940. Unpublished study prepared by Nippon Soda Co., Ltd. 25 p. 

44651852 Murli, H. (1998) Mutagenicity Test on NI-25 in an in vivo Mouse Micronucleus Assay: Second 

Amended Second Revised Final Report: Lab Project Number: 15901-0-455: 20996: 455. Unpublished 

study prepared by Hazleton Washington, Inc. 32 p. 

44651853 San, R.; Sly, J. (1997) Unscheduled DNA Synthesis (UDS) Test with Mammalian Liver Cells in vivo: 

Acetamiprid: Amended Final Report: Lab Project Number: G97AG26.381. Unpublished study prepared 

by Microbiological Associates, Inc. 69 p. 

44651854 Durward, R. (1998) NI-25: Metaphase Analysis in the Rat Bone Marrow in vivo: Lab Project Number: 

235/017R2. Unpublished study prepared by Safepharm Laboratories Limited. 32 p. 

44651855 Kanaguchi, Y. (1997) Acetamiprid--Chromosomal Aberration Study in Chinese Hamster Ovary (CHO) 

Cells: Lab Project Number: G-0800: 9728. Unpublished study prepared by Nippon Soda Company, Ltd. 

29 p. 

44651856 Ham, A. (1998) Genotoxicity Test on NI-25 in the Assay for Unscheduled DNA Synthesis in Rat Liver 

Primary Cell Cultures with A Confirmatory Assay: Second Amended Third Revised Final Report: Lab 

Project Number: 15901-0-447R: 20991: 447R. Unpublished study prepared by Hazleton Washington, 

Inc. 41 p. 

44651857 Adams, K. (1998) Acetamiprid: Mammalian Cell Mutation Assay: Lab Project Number: NOD 

006/971139. Unpublished study prepared by Huntingdon Life Sciences Ltd. 27 p. 

44988431 Cifone, M. (1998) Mutagenicity Test on IM-1-4 in the CHO/HGPRT Forward Mutation Assay: Final 

Report: Lab Project Number: 6840-106: 18981-0-435. Unpublished study prepared by Covance 

Laboratories, Inc. 52 p. 

44988432 Mochizuki, N.; Kanaguchi, Y. (1997) IM-0--Reverse Mutation Study on Bacteria: Lab Project Number: 

G-949: 9862. Unpublished study prepared by Nippon Soda Co., Ltd. 25 p. 

44988433 Mochizuki, N.; Kanaguchi, Y. (1997) IM-2-1--Reverse Mutation Study on Bacteria: Lab Project 

Number: G-932: 9851. Unpublished study prepared by Nippon Soda Co., Ltd. 25 p. 

44988501 Curry, P. (1998) Mutagenicity Test on IM-1-4 in the In Vivo Mouse Micronucleus Assay: Final Report: 

Lab Project Number: 18981-0-455OECD. Unpublished study prepared by Covance Labs., Inc. 58 p. 
102 

44988502 Mochizuki, N.; Kanaguchi, Y. (1994) IC-0--Reverse Mutation Study on Bacteria: Lab Project Number: 

G-942: 9854. Unpublished study prepared by Nippon Soda Co., Ltd. 25 p. 

General metabolism 

44651858 Cheng, T. (1997) Dermal Absorption of (carbon 14) NI-25 in Male Rats (Preliminary and Definitive 

Phases): Final Report: Lab Project Number: COVANCE 6224-237: MC-5577. Unpublished study 

prepared by Covance Laboratories Inc. 160 p. 

44988503 Mori, H.; Tanoue, T. (1997) (Carbon-14)-NI-25--Metabolism Study in Rats: (A Summary Report): Lab 

Project Number: EC-912. Unpublished study prepared by Nisso Chemical Analysis Service Co., Ltd. 47 

p. 

44988504 Mori, H.; Tanoue, T. (1997) (Carbon-14)-NI-25--Metabolism Study in Rats: (Qualitative and 

Quantitative Analysis of Metabolites in Group C): Amended Final Report: Lab Project Number: 95-108: 

EC-842-1. Unpublished study prepared by Nisso Chemical Analysis Service Co., Ltd. 81 p. 

44988505 Mori, H.; Tanoue, T. (1997) (Carbon-14)-NI-25--Metabolism Study in Rats: Lab Project Number: EC724: 2-94. Unpublished study prepared by Nisso Chemical Analysis Service Co., Ltd. 661 p. 

44988506 Premkumar, N.; Guo, C.; Vengurlekar, S. (1995) Adsorption, Distribution, Metabolism, Elimination, 

and Pharmacokinetics After Chronic Dosing of (carbon-14)-NI-25 in Rats: Lab Project Number: 42207. 

Unpublished study prepared by ABC Labs., Inc. 221 p. 

44988507 Premkumar, N.; Guo, C. (1995) (Carbon-14)-NI-25--Biliary Excretion in Rat: Final Report: Lab Project 

Number: 42206. Unpublished study prepared by ABC Labs., Inc. 96 p. 

Seed Germination/Seedline Emergence and Vegetable Vigor 

44988413 Teixiera, D. (1999) Acetamiprid--Determination of Effects on Seedling Emergence and Vegetative 

Vigor of Ten Plant Species: Final Report: Lab Project Number: 97-12-7184: 10566.0397.6416.610. 

Unpublished study prepared by Springborn Laboratories, Inc. 265 p. 

45921401 Teixeira, D. (2003) Acetamiprid--Determination of Effects on Vegetative Vigor of Lettuce (Lactuca 

sativa): Lab Project Number: 12681.6107. Unpublished study prepared by Springborn Smithers 

Laboratories. 73 p. OPPTS 850.4150 and 850.4250 

Aquatic plant growth 

44988414 Hoberg, J. (1997) Acetamiprid Technical--Toxicity to the Freshwater Green Alga Selenastrum 

capricornutum: Final Report: Lab Project Number: 97-5-6987: 10566.0297.6410.430. Unpublished 

study prepared by Springborn Laboratories, Inc. 57 p. 

44988415 Hoberg, J. (1997) Acetamiprid Technical--Toxicity to Duckweed, Lemna gibba: Final Report: Lab 

Project Number: 97-7-7029: 10566.0397.6415.410. Unpublished study prepared by Springborn 

Laboratories, Inc. 63 p. 

44988416 Hoberg, J. (1997) Acetamiprid Technical--Toxicity to the Fresh Water Blue-Green Alga, Anabaena flosaquae: Final Report: Lab Project Number: 97-6-7008: 10566.0397.6414.420. Unpublished study 

prepared by Springborn Laboratories, Inc. 57 p. 

44988417 Hoberg, J. (1997) Acetamiprid Technical-Toxicity to the Freshwater Diatom Navicula pelliculosa: Final 

Report: Lab Project Number: 97-6-7005: 10566.0397.6412.440. Unpublished study prepared by 

Springborn Laboratories, Inc. 58 p. 

44988418 Hoberg, J. (1997) Acetamiprid Technical--Toxicity to the Marine Diatom Skeletonema costatum: Final 
103 

Report: Lab Project Number: 97-6-7028: 10566.0397.6413.450. Unpublished study prepared by 

Springborn Laboratories, Inc. 57 p. 

Seed germination/seedling emergence and vegetative vigor 

44988413 Teixiera, D. (1999) Acetamiprid--Determination of Effects on Seedling Emergence and Vegetative 

Vigor of Ten Plant Species: Final Report: Lab Project Number: 97-12-7184: 10566.0397.6416.610. 

Unpublished study prepared by Springborn Laboratories, Inc. 265 p. 

45921401 Teixeira, D. (2003) Acetamiprid--Determination of Effects on Vegetative Vigor of Lettuce (Lactuca 

sativa): Lab Project Number: 12681.6107. Unpublished study prepared by Springborn Smithers 

Laboratories. 73 p. OPPTS 850.4150 and 850.4250 

Dissipation of Dislodgeable Foliar & Soil Residues 

45323001 Willard, T. (2001) Acetamiprid: Dissipation of Dislodgeable Residue on Cotton: Final Study Report: 

Lab Project Number: 97512640. Unpublished study prepared by Aventis CropScience. 371 p. OPPTS 

875.2100 

Honey bee acute contact 

44651874 Candolfi, M. (1997) NI-25 (Acetamiprid): Laboratory Oral and Contact Toxicity Test with the 

Honeybee, Apis mellifera: Lab Project Number: 96-045-1013: 1013.018.265: 3.5.96/BEE NI-25. 

Unpublished study prepared by Springborn Laboratories (Europe) AG. 50 p. 

45932503 Kling, A. (2003) Acute Contact and Oral Toxicity of EXP 60707A to the Bumble-Bee Bombus terrestris 

L. Under Laboratory Conditions: (Final Report): Lab Project Number: 20021073/02-BLEU: EXP 60707 

A. Unpublished study prepared by GAB Biotechnologie GmbH. 33 p. 

Honey bee residue on foliage 

44651875 Collins, M. (1998) Evaluation of Toxicity of Residues of Acetamiprid (NI-25) on Alfalfa to Honey Bees 

(Apis mellifera): Final Report: Lab Project Number: 98-1-7214: 10566.0897.6449.266: 1412-97-004-09-

21F-01. Unpublished study prepared by Landis International, Inc. and Springborn Laboratories, Inc. 80 

p. 

45346901 Hoberg, J. (2001) Evaluation of Toxicity of Residues of Acetamiprid (NI-25) and Procure 50WS on 

Alfalfa to Honey Bees (Apis mellifera): Lab Project Number: 13726.6123: 041100. Unpublished study 

prepared by Springborn Labs., Inc. 40 p. OPPTS 850.3030 

45932502 Saika, O. (2003) Acetamiprid: Toxicity of Foliar Residue to Honey Bees: Lab Project Number: RD03115. Unpublished study prepared by Nippon Soda Co., Ltd. 14 p. 

Field test for pollinators 

45932504 Schur, A. (2002) A Semi-Field Study on the Effects on Honey Bees (Apis mellifera L.) of Assail 70 WP 

(EXP61842A, Acetamiprid 70%) Straight and in Combination with the Fungicide Procure 50WS 

(Triflumizole 50%): (Final Report): Lab Project Number: 20011239/S1-BZEU: EXP61842A. 

Unpublished study prepared by GAB Biotechnologie GmbH. 54 p. 

45932505 Schur, A. (2003) A Semi-Field Study on the Effects of a Foliar Application of EXP60707 A 

(Acetamiprid 20% SP) on the Brood Development of the Honey Bee (Apis mellifera L.): (Final Report): 

Lab Project Number: 20011073/01-BZEU: EXP60707A. Unpublished study prepared by GAB 

Biotechnologie GmbH. 88 p. 
104 

Fish early-life stage toxicity test 

46729101 Saika, O. (2005) Response to Data Evaluation Report on the Toxicity of Acetamiprid (NI-25) to Fathead 

Minnow (Pimephales promelas), Fish Early Life Cycle (MRID 44651872). Project Number: 

NAI/06/002, SA/96123. Unpublished study prepared by Nippon Soda Co., Ltd. 83 p. 

Avian acute oral toxicity test 

48407701 Hubbard, P. (2011) Acetamiprid: An Acute Oral Toxicity Study with the Zebra Finch (Poephila guttata). 

Project Number: 437/119. Unpublished study prepared by Wildlife International, Ltd. 76 p. 

Avian reproduction test 

46014801 Brewer, L.; Bowers, L. (2003) Reply to EPA Data Evaluation Record (DER) for a Northern Bobwhite 

Reproduction Study with Acetamiprid. Project Number: NAI/03/001. Unpublished study prepared by 

Springborn Smithers Laboratories. 

46369201 Stafford, J. (2004) Acetamiprid (NI-25) - Reproductive Toxicity Test with Mallard Duck (Anas 

platyrhynchos). Project Number: 13798/4105. Unpublished study prepared by Springborn Smithers 

Laboratories. 153 p. 

46555601 Temple, D.; Martin, K.; Beavers, J.; et. al. (2005) Acetamiprid: A Reproductive Study with the Northern 

Bobwhite. Project Number: 437/104. Unpublished study prepared by Wildlife International, Ltd. 186 p. 

46717701 Brewer, L. (2005) Response to EPA DER for Acetamiprid (NI-25) - Reproductive Toxicity Test with 

Mallard Duck (Anas platyrhynchos). Project Number: NAI/05/001. Unpublished study prepared by 

Springborn Smithers Laboratories. 17 p. 

Honey bee toxicity of residues on foliage 

47737801 Walsh, D. (2009) Pollinator Pesticide Safety Trials 2007: Flonicamid. Project Number: 

IB/2009/PH/002/01. Unpublished study prepared by Washington State University. 19 p. 

Acute oral toxicity 

46271906 Li, K. (2004) Acetamiprid (F5025) Ant & Roach Baits: Acute Oral Toxicity (in Rats) Studies and 

Waiver Request for Acute Dermal and Inhalation Toxicity, Eye and Skin Irritation and Skin 

Sensitization Studies. Project Number: P/3680, 3223/30, A2003/5722. Unpublished study prepared by 

FMC Corp Agricultural Products Group and Charles River Laboratories, Inc. 109 p. 

46342702 Allen, D. (1997) NI-25 WSG: Acute Oral Toxicity Test in the Rat. Project Number: 235/148. 

Unpublished study prepared by Safepharm Laboratories, Ltd. 32 p. 

46432802 Cerven, D. (2004) F4688: Acute Oral Toxicity (In Rats) - Up and Down Procedure (UDP). Project 

Number: A2004/5837, 1010/01, MB/04/12712/01. Unpublished study prepared by MB Research 

Laboratories. 24 p. 

46685502 Patterson, D. (2001) An Acute Oral Toxicity Study in Rats with Acetamiprid 50 SF (EXP 81141A). 

Project Number: 3522/19. Unpublished study prepared by Springborn Laboratories, Inc. (SLI). 65 p. 

46794304 Rodabaugh, D. (2006) An Acute Oral Toxicity Study in Rats with Acetamiprid 0.075% Ant Bait 

(Up/Down Study Design). Project Number: KZH00078, 000TSC05512, A2005/5953. Unpublished 

study prepared by Charles River Laboratories, Inc. 45 p. 

46794306 Nuber, D. (2006) Acetamiprid Gel Baits (0.35% and 0.075%) Waiver Request for Acute Inhalation 

Toxicity. Project Number: P/3813. Unpublished study prepared by FMC Corp. 18 p. 
105 

46860202 Oshio, I. (2005) Acute Oral Toxicity Study of Acetamiprid 9.25 SL in Rats. Project Number: H262. 

Unpublished study prepared by Nippon Soda Co., Ltd. 24 p. 

46860203 Takaori, H. (2006) Acute Oral Toxicity Study of Acetamiprid 9.25 SL in Rats - Second Study. Project 

Number: H285. Unpublished study prepared by Nippon Soda Co., Ltd. 20 p. 

47838505 Griffon, B. (2001) Acetamiprid CEL 26521 SL: Acute Oral Toxicity in Rats. Project Number: 

22016/TAR, 22016/TAR/CEL/265/21/SL/SCOTTS/FRANCE/SAS. Unpublished study prepared by 

Centre International de Toxicologie. 24 p. 

47848104 Griffon, B. (2003) UKSO48A: Acute Oral Toxicity in Rats: "Acute Toxicity Class Method". Project 

Number: 25496/TAR. Unpublished study prepared by Centre International de Toxicologie. 27 p. 

47868802 Rodabaugh, D. (2009) An Acute Oral Toxicity Study in Rats with EQEF 303 F5688 Insecticide 

(Up/Down Study Design). Project Number: KZH00123, A2006/6091. Unpublished study prepared by 

Charles River Laboratories, Inc. 55 p. 

48327303 Wrubel, J. (2010) F7180-8 Fly Sticker Insecticide: Request for Bridging of Acute Toxicity Data 

Requirements. Project Number: NAI/10/004. Unpublished study prepared by Nisso America, Inc. 5 p. 

48404404 Durando, J. (2011) GWN-9857: Acute Oral Toxicity Up and Down Procedure in Rats. Project Number: 

29853, P320/UDP. Unpublished study prepared by Eurofins/Product Safety Laboratories. 20 p. 

48463104 Durando, J. (2011) RF2157 Bait: Acute Oral Toxicity Up and Down Procedure in Rats. Project Number: 

30975, P320/UDP/WEL. Unpublished study prepared by Eurofins/Product Safety Laboratories. 16 p. 

48584601 Wolf, T. (2011) "AMP 44 RB": Acute Oral Toxicity Study with Rats (Up-and-Down Procedure). Project 

Number: KW173. Unpublished study prepared by Seibersdorf Labor GmbH. 31p. 

Acute dermal toxicity 

46342703 Allen, D. (1997) NI-25 WSG: Acute Dermal Toxicity (Limit Test) in the Rat. Project Number: 235/150. 

Unpublished study prepared by Safepharm Laboratories, Ltd. 18 p. 

46432803 Gilotti, A. (2004) F4688: Acute Dermal Toxicity/LD50 in Rabbits. Project Number: A2004/5838, 

MB/04/12712/02, 1100/02. Unpublished study prepared by MB Research Laboratories. 25 p. 

46685503 Patterson, D. (2001) An Acute Dermal Toxicity Study in Rabbits with Acetamiprid 50 SF 

(EXP81141A). Project Number: 3522/20. Unpublished study prepared by Springborn Laboratories, Inc. 

(SLI). 29 p. 

46794305 Rodabaugh, D. (2006) An Acute Dermal Toxicity Study in Rats with Acetamiprid 0.075% Ant Bait. 

Project Number: KZH00079, A2005/5952, 000TSC05512. Unpublished study prepared by Charles 

River Laboratories, Inc. 53 p. 

46794306 Nuber, D. (2006) Acetamiprid Gel Baits (0.35% and 0.075%) Waiver Request for Acute Inhalation 

Toxicity. Project Number: P/3813. Unpublished study prepared by FMC Corp. 18 p. 

46860204 Sanders, A. (2006) Acetamprid 9.25 SL: Acute Dermal Toxicity (Limit Test) in the Rat. Project 

Number: 235/494R. Unpublished study prepared by Safepharm Laboratories Ltd. 19 p. 

47838506 Griffon, B. (2001) CEL 26521 SL: Acute Dermal Toxicity in Rats. Project Number: 22017/TAR, 

22017/TAR/CEL/265/21/SL/SCOTTS/FRANCE/SAS. Unpublished study prepared by Centre 

International de Toxicologie. 26 p. 

47848105 Griffon, B. (2003) UKSO48A: Acute Dermal Toxicity in Rats. Project Number: 25497/TAR. 

Unpublished study prepared by Centre International de Toxicologie. 27 p. 

47868803 Rodabaugh, D. (2009) An Acute Dermal Toxicity Study in Rats with EQEF 303 F5688 Insecticide. 
106 

Project Number: KZH00133, A2006/6093. Unpublished study prepared by Charles River Laboratories, 

Inc. 56 p. 

48327303 Wrubel, J. (2010) F7180-8 Fly Sticker Insecticide: Request for Bridging of Acute Toxicity Data 

Requirements. Project Number: NAI/10/004. Unpublished study prepared by Nisso America, Inc. 5 p. 

48404405 Durando, J. (2010) GWN-9857: Acute Dermal Toxicity Study in Rats: Limit Test. Project Number: 

29854, P322/RAT. Unpublished study prepared by Eurofins/Product Safety Laboratories. 15 p. 

48463105 Durando, J. (2011) RF2157 Bait: Acute Dermal Toxicity Study in Rats. Project Number: 

P322/RAT/WEL, 30976. Unpublished study prepared by Eurofins/Product Safety Laboratories. 15 p. 

Acute inhalation toxicity 

46432804 Gilotti, A. (2004) F4688: Acute Inhalation Toxicity/LC50 in Rats. Project Number: A2004/5840, 

1300/02, MB/04/12712/05. Unpublished study prepared by MB Research Laboratories. 35 p. 

46685504 Patterson, D. (2001) An Acute Nose-Only Inhalation Toxicity Study in Rats with Acetamiprid 50 SF 

(EXP 81141A). Project Number: 3522/24. Unpublished study prepared by Springborn Laboratories, Inc. 

(SLI). 53 p. 

46794306 Nuber, D. (2006) Acetamiprid Gel Baits (0.35% and 0.075%) Waiver Request for Acute Inhalation 

Toxicity. Project Number: P/3813. Unpublished study prepared by FMC Corp. 18 p. 

46860205 Griffiths, D. (2005) Acetamprid 9.25 SL: Acute Inhalation Toxicity (Nose Only) Study in the Rat. 

Project Number: 235/492R. Unpublished study prepared by Safepharm Laboratories Ltd. 37 p. 

47838507 Restum, J. (2009) Acetamiprid Concentrate Insecticide Waiver Request from Further Testing: Acute 

Inhalation Toxicity LC50. Project Number: NAI/09/004. Unpublished study prepared by The Scotts 

Company. 6 p. 

47848106 Restum, J (2009) Acetamiprid + Triticonazole Concentrate Insecticide and Fungicide: Waiver Request 

from Further Testing: Acute Inhalation Toxicicty LC50. Project Number: NAI/09/003. Unpublished 

study prepared by The Scotts Company. 6 p. 

47868804 Rodabaugh, D. (2006) An Acute Nose-Only Inhalation Study in Rats with EQEF 303 F5688. Project 

Number: KZH00136, A2006/6092. Unpublished study prepared by Charles River Laboratories, Inc. 71 

p. 

48327303 Wrubel, J. (2010) F7180-8 Fly Sticker Insecticide: Request for Bridging of Acute Toxicity Data 

Requirements. Project Number: NAI/10/004. Unpublished study prepared by Nisso America, Inc. 5 p. 

48404406 Durando, J. (2010) GWN-9857: Acute Inhalation Toxicity Study in Rats. Project Number: 29855, P330. 

Unpublished study prepared by Eurofins/Product Safety Laboratories. 24 p. 

48463106 Mizens, M. (2011) RF2157 Bait: Request for Waiver of Tier 1 Pesticide Data Requirements. Project 

Number: 3948. Unpublished study prepared by Wellmark International. 16 p. 

Acute eye irritation 

46342704 Allen, D. (1997) NI-25 WSG: Primary Eye Irritation Test in the Rabbit. Project Number: 235/152. 

Unpublished study prepared by Safepharm Laboratories, Ltd. 22 p. 

46432805 Hoff, T. (2004) F4688: Acute Eye Irritation in Rabbits. Project Number: A2004/5806, MB/04/12623/04, 

1200/02. Unpublished study prepared by MB Research Laboratories. 20 p. 

46685505 Patterson, D. (2001) A Primary Eye Irritation Study in Rabbits with Acetamiprid 50 SF (EXP 81141A). 

Project Number: 3522/21. Unpublished study prepared by Springborn Laboratories, Inc. (SLI). 29 p. 
107 

46794306 Nuber, D. (2006) Acetamiprid Gel Baits (0.35% and 0.075%) Waiver Request for Acute Inhalation 

Toxicity. Project Number: P/3813. Unpublished study prepared by FMC Corp. 18 p. 

46794307 Rodabaugh, D. (2006) A Primary Eye Irritation Study in Rabbits with Acetamiprid 0.075% Ant Bait. 

Project Number: KZH00080, A2005/5954. Unpublished study prepared by Charles River Laboratories, 

Inc. 45 p. 

46860206 Oshio, I. (2005) Acute Eye Irritation/Corrosion Study of Acetamiprid 9.25 SL in Rabbits. Project 

Number: H263. Unpublished study prepared by Nippon Soda Co., Ltd. 20 p. 

47838508 Griffon, B. (2001) CEL 26521 SL: Acute Eye Irritation in Rabbits. Project Number: 22019/TAL, 

22019/TAL/CEL/265/21/SL/SCOTTS/FRANCE/SAS. Unpublished study prepared by Centre 

International de Toxicologie. 20 p. 

47848107 Griffon, B. (2003) UKSO48A: Acute Eye Irritation in Rabbits. Project Number: 25499/TAL. 

Unpublished study prepared by Centre International de Toxicologie. 28 p. 

47868805 Rodabaugh, D. (2006) A Primary Eye Irritation Study in Rabbits with EQEF 303 F5688 Insecticide. 

Project Number: KZH00124, A2006/6089. Unpublished study prepared by Charles River Laboratories, 

Inc. 47 p. 

48327303 Wrubel, J. (2010) F7180-8 Fly Sticker Insecticide: Request for Bridging of Acute Toxicity Data 

Requirements. Project Number: NAI/10/004. Unpublished study prepared by Nisso America, Inc. 5 p. 

48404407 Durando, J. (2010) GWN-9857: Primary Eye Irritation Study in Rabbits. Project Number: 29856, P324. 

Unpublished study prepared by Eurofins/Product Safety Laboratories. 17 p. 

48463106 Mizens, M. (2011) RF2157 Bait: Request for Waiver of Tier 1 Pesticide Data Requirements. Project 

Number: 3948. Unpublished study prepared by Wellmark International. 16 p. 

48463107 Durando, J. (2011) RF2157 Bait: Primary Eye Irritation Study in Rabbits. Project Number: P324/WEL, 

30977. Unpublished study prepared by Eurofins/Product Safety Laboratories. 11 p. 

Acute dermal irritation 

46342705 Allen, D. (1997) NI-25 WSG: Primary Dermal Irritation Test in the Rabbit. Project Number: 235/151. 

Unpublished study prepared by Safepharm Laboratories, Ltd. 13 p. 

46432806 Hoff, T. (2004) F4688: Acute Dermal Irritation in Rabbits. Project Number: A2004/5839, 1130/02, 

MB/04/12712/03. Unpublished study prepared by MB Research Laboratories. 22 p. 

46685506 Patterson, D. (2001) A Primary Skin Irritation Study in Rabbits with Acetamiprid 50 SF (EXP 81141A). 

Project Number: 3522/22. Unpublished study prepared by Springborn Laboratories, Inc. (SLI). 28 p. 

46794306 Nuber, D. (2006) Acetamiprid Gel Baits (0.35% and 0.075%) Waiver Request for Acute Inhalation 

Toxicity. Project Number: P/3813. Unpublished study prepared by FMC Corp. 18 p. 

46794308 Rodabaugh, D. (2006) A Primary Skin Irritation Study in Rabbits with Acetamiprid 0.075% Ant Bait. 

Project Number: KZH00081, A2005/5955. Unpublished study prepared by Charles River Laboratories, 

Inc. 45 p. 

46860207 Sanders, A. (2006) Acetamprid 9.25 SL: Acute Dermal Irritation in the Rabbit. Project Number: 

235/495R. Unpublished study prepared by Safepharm Laboratories Ltd. 15 p. 

47838509 Griffon, B. (2001) CEL 26521 SL: Acute Dermal Irritation in Rabbits. Project Number: 22018/TAL, 

22018/TAL/CEL/265/21/SL/SCOTTS/FRANCE/SAS. Unpublished study prepared by Centre 

International de Toxicologie. 32 p. 
108 

47848108 Griffin, B. (2003) UKSO48A: Acute Dermal Irritation in Rabbits. Project Number: 25498/TAL. 

Unpublished study prepared by Centre International de Toxicologie. 22 p. 

47868806 Rodabaugh, D. (2006) A Primary Skin Irritation Study in Rabbits with EQEF 303 F5688 Insecticide. 

Project Number: KZH00134, A2006/6090. Unpublished study prepared by Charles River Laboratories, 

Inc. 45 p. 

48327303 Wrubel, J. (2010) F7180-8 Fly Sticker Insecticide: Request for Bridging of Acute Toxicity Data 

Requirements. Project Number: NAI/10/004. Unpublished study prepared by Nisso America, Inc. 5 p. 

48404408 Durando, J. (2010) GWN-9857: Primary Skin Irritation Study in Rabbits. Project Number: 29857, P326. 

Unpublished study prepared by Eurofins/Product Safety Laboratories. 16 p. 

48463108 Durando, J. (2011) RF2157 Bait: Primary Skin Irritation Study in Rabbits. Project Number: P326/WEL, 

30978. Unpublished study prepared by Eurofins/Product Safety Laboratories. 16 p. 

Skin sensitization 

46342706 Allen, D. (1997) NI-25 WSG: Buehler Delayed Contact Hypersensitivity Study in the Guinea Pig. 

Project Number: 235/153. Unpublished study prepared by Safepharm Laboratories, Ltd. 36 p. 

46432807 Hall, D. (2004) F4688: Delayed Contact Dermal Sensitization Test - Buehler Method. Project Number: 

A2004/5841, MB/04/12712/06, 1160/02. Unpublished study prepared by MB Research Laboratories. 54 

p. 

46685507 Patterson, D. (2001) A Dermal Sensitization Study in Guinea Pigs with Acetamiprid 50 SF (EXP 

81141A) - Modified Buehler Design. Project Number: 3522/23, 999/150. Unpublished study prepared 

by Springborn Laboratories, Inc. (SLI). 46 p. 

46794306 Nuber, D. (2006) Acetamiprid Gel Baits (0.35% and 0.075%) Waiver Request for Acute Inhalation 

Toxicity. Project Number: P/3813. Unpublished study prepared by FMC Corp. 18 p. 

46794309 Rodabaugh, D. (2006) A Dermal Sensitization Study in Guinea Pigs With Acetamiprid 0.075% Ant Bait 

Modified Buehler Design. Project Number: KZH00082, A2005/5956. Unpublished study prepared by 

Charles River Laboratories, Inc. 65 p. 

46860208 Sanders, A. (2006) Acetamprid 9.25 SL: Local Lymph Node Assay in the Mouse. Project Number: 

235/496R. Unpublished study prepared by Safepharm Laboratories Ltd. 23 p. 

47838510 Griffon, B. (2001) CEL 26521 SL: Skin Sensitization Test in Guinea Pigs; Buehler. Project Number: 

22020/TSG, 22020/TSG/CEL/265/21/SL/SCOTTS/FRANCE/SAS. Unpublished study prepared by 

Centre International de Toxicologie. 32 p. 

47848109 Griffon, B. (2003) UKSO48A: Skin Sensitization Test in Guinea Pigs: (Modified Buehler Test: 9 

Applications). Project Number: 25646/TSG. Unpublished study prepared by Centre International de 

Toxicologie. 37 p. 

47868807 Rodabaugh, D. (2006) A Dermal Sensitization Study in Guinea Pigs with EQEF 303 F5688 Insecticide: 

Modified Buehler Design. Project Number: KZH00135, A2006/6094. Unpublished study prepared by 

Charles River Laboratories, Inc. 65 p. 

48327303 Wrubel, J. (2010) F7180-8 Fly Sticker Insecticide: Request for Bridging of Acute Toxicity Data 

Requirements. Project Number: NAI/10/004. Unpublished study prepared by Nisso America, Inc. 5 p. 

48404409 Durando, J. (2010) GWN-9857: Dermal Sensitization Study in Guinea Pigs (Buehler Method). Project 

Number: 29858, P328. Unpublished study prepared by Eurofins/Product Safety Laboratories. 28 p. 

48463109 Durando, J. (2011) RF2157 Bait: Dermal Sensitization Study in Guinea Pigs (Buehler Method). Project 
109 

Number: P328/WEL, 30979. Unpublished study prepared by Eurofins/Product Safety Laboratories. 25 p.

Developmental neurotoxicity study 

46255619 Nemec, M. (2003) An Oral Developmental Neurotoxicity Study of Acetamiprid in Rats. Project 

Number: WIL/21193. Unpublished study prepared by WIL Research Laboratories, Inc. 1643 p. 

46779201 Nemec, M.; Beck, M.; Sloter, E. (2006) Rebuttal of Data Evaluation Record for Acetamiprid (WIL No. 

21193, EPA Acetamiprid 099050, MRID 46255619). Project Number: NAI/06/004, WIL/21193B. 

Unpublished study prepared by WIL Research Laboratories, Inc. 313 p. 

46779202 Nemec, M. (2004) A Dose Range-Finding Study for a Developmental Neurotoxicity Study of 

Acetamiprid in Rats. Project Number: WIL/21192. Unpublished study prepared by WIL Research 

Laboratories, Inc. 599 p. 

46779203 Schaefer, G. (2006) Validation of Developmental Neurotoxicity Endpoints in Rats Administered 

Methimazole in Drinking Water. Project Number: WIL/99199. Unpublished study prepared by WIL 

Research Laboratories, Inc. 40 p. 

46779204 Pitt, J. (2006) A Validation Study for Developmental Neurotoxicity Endpoints at WIL Research 

Laboratories, Inc.: Effect of Proylthiouracil (PTU) on Developmental Neurotoxicity Endpoints in 

Crl:CD (SD) IGS BR Rats (WIL-99126). Project Number: WIL/99126. Unpublished study prepared by 

WIL Research Laboratories, Inc. 17 p. 

47237401 Li, A.; Lau, E. (2007) Acetamiprid DNT Study (WIL-21193; MRID 46255619): Response to EPA CEB 

Statistical Analyses and Weight of Evidence Supporting NOAEL of 10 mg/kg bwt/day. Project Number: 

WD0771/000/E0T0. Unpublished study prepared by Exponent Inc. 51 p. 

Immunotoxicity 

48113401 Brown, L. (2010) Acetamiprid: 4-Week Dietary Immunotoxicity Study in the Mouse. Project Number: 

LGG0005. Unpublished study prepared by Huntingdon Life Sciences, Ltd. 176 p. 

48113402 Moore, E. (2010) Acetamiprid: 4-Week Dietary Immunotoxicity Study in the Rat. Project Number: 

LGG0004. Unpublished study prepared by Huntingdon Life Sciences, Ltd. 193 p. 

Aquatic invertebrate acute toxicity, test, freshwater daphnids 

46255608 Saito, S. (2002) IM-1-5 (N-((6-Chloro-3-Pyridyl) methyl)-N-Methylacetamidine): Acute Toxicity to 

Daphnia magna. Project Number: NCAS/02/197. Unpublished study prepared by Nisso Chemical 

Analysis Service Co., Ltd. 23 p. 

15.2.A. Physical Chemical and Fate Data 

Solubility 

44651810 Gomyo, T.; Kobayashi, S. (1997) NI-25--Solubility in Organic Solvents: Amended Final Report: Lab 

Project Number: NISSO 2-83: EC-376-3: 2-83. Unpublished study prepared by Nisso Chemical 

Analysis Service Co., Ltd. 32 p. 

44651811 Gomyo, T.; Kobayashi, S. (1997) NI-25--Solubility in Water: Amended Final Report: Lab Project 

Number: NISSO 2-81: EC-377-3: 2-81. Unpublished study prepared by Nisso Chemical Analysis 

Service Co., Ltd. 37 p. 

Vapor Pressure 

44651812 Gomyo, T.; Kobayashi, S. (1997) NI-25--Vapor Pressure: Amended Final Report: Lab Project Number: 
110 

NISSO 2-79: EC-372-2: 2-79. Unpublished study prepared by Nisso Chemical Analysis Service Co., 

Ltd. 43 p. 

Dissociation Constant 

44651813 Gomyo, T.; Kobayashi, S. (1997) NI-25--Dissociation Constant in Water (pKa): Amended Final Report: 

Lab Project Number: NISSO 2-88: EC-371-2: 2-88. Unpublished study prepared by Nisso Chemical 

Analysis Service Co., Ltd. 30 p. 

Oct/Water partition Coef. 

44651814 Gomyo, T.; Kobayashi, S. (1997) NI-25--Octanol/Water Partition Coefficient: Amended Final Report: 

Lab Project Number: NISSO 2-84: EC-378-2: 2-84. Unpublished study prepared by Nisso Chemical 

Analysis Service Co., Ltd. 34 p. 

Hydrolysis 

44651876 Gomyo, T.; Kobayashi, S. (1997) NI-25--Hydrolysis: Amended Final Report: Lab Project Number: 

NISSO 2-89: EC-375-2: 2-89. Unpublished study prepared by Nisso Chemical Analysis Service Co., 

Ltd. 126 p. 

44651877 Class, T. (1997) Hydrolysis of IM-1-4 and IC-0 (Two Degradates of Acetamiprid) as a Function of pH: 

Lab Project Number: P 225 G: B 225 G: 97-32. Unpublished study prepared by PTRL Europe. 24 p. 

Photodegradation-water 

44988509 Hausmann, S.; Class, T. (1998) Aqueous Photodegradation of (carbon-14)-Acetamiprid at pH 7 and 

Determination of Quantum Yield: Lab Project Number: P196G: B196G: 96-82. Unpublished study 

prepared by PTRL, West PTRL, Europe. 124 p. 

44988510 Emeric, G. (1998) Acetamiprid--Verification of the Identity of the Photolyte Obtained at pH 7--Study: 

Lab Project Number: 98-47. Unpublished study prepared by Rhone-Poulenc Agro. 36 p. 

44988511 Mamouni, A. (1997) Aqueous Photolysis of (carbon-14)-IM-1-4 Under Laboratory Conditions: Lab 

Project Number: 671332: 97-166. Unpublished study prepared by RCC Umweltchemie. 64 p. 

Photodegradation-soil 

44988508 Mislankar, S. (1998) Acetamiprid (NI-25) Soil Photolysis: Lab Project Number: EC-97-359: F97125-

806: EC-97-359-HP. Unpublished study prepared by Rhone-Poulenc Ag Company. 149 p. 

Aerobic soil metabolism 

44651879 Feung, C. (1998) Acetamiprid (NI-25): Aerobic Soil Metabolism: Lab Project Number: EC-96-351. 

Unpublished study prepared by Rhone-Poulenc Ag Company. 122 p. 

44651880 Feung, C. (1998) Acetamiprid (NI-25): Metabolism in Collombey Soil: Lab Project Number: EC-97-

406. Unpublished study prepared by Rhone-Poulenc Ag Company. 78 p. 

44651881 Burr, C. (1997) (Carbon 14)-NI-25: Rate of Aerobic Degradation in Three Soil Types at 20 (degrees 

Centigrade) and One Soil Type at 10 (degrees Centigrade): Lab Project Number: 11256: 201445. 

Unpublished study prepared by Rhone-Poulenc Agriculture Limited. 213 p. 

44651882 Lowden, P.; Oddy, A.; Jones, M. (1997) NI-25: Rate of Degradation of the Acid Metabolite, (carbon 

14)-IC-O in Three Soils: Lab Project Number: 11257: 20147. Unpublished study prepared by Rhone-
111 

Poulenc Agriculture Limited. 153 p. 

44699101 Morgenroth, U. (1997) (Carbon 14)-NI-25: Metabolism in One Soil Incubated Under Aerobic 

Conditions: Lab Project Number: 373994. Unpublished study prepared by RCC Umweltchemie AG. 125 

p. 

Anaerobic aquatic metab. 

44988512 Feung, C. (1999) Acetamiprid (NI-25): Anaerobic Aquatic Metabolism: Lab Project Number: EC-97-

404. Unpublished study prepared by Rhone-Poulenc Ag Co. 128 p. 

Aerobic aquatic metab. 

44988513 Andrawes, N. (1999) Acetamiprid (NI-25): Aerobic Aquatic Metabolism: Lab Project Number: EC-96-

352. Unpublished study prepared by Rhone-Poulenc Ag Co. 143 p. 

Leach/adsorp/desorption 

44651883 Liu, A. (1997) Acetamiprid (NI-25): Soil Adsorption/Desorption Study: Lab Project Number: EC-97-

381: F97525-001: RP397ACL. Unpublished study prepared by Rhone-Poulenc Ag Company. 180 p. 

44651884 Liu, A. (1997) 6-Chloronicotinic Acid (Acetamiprid Metabolite): Soil Adsorption/Desorption Study: 

Lab Project Number: EC-97-370: F97525-001: RP397ACL. Unpublished study prepared by RhonePoulenc Ag Company. 195 p. 

44651885 Liu, A. (1998) (Carbon 14)-N-methyl-(6-chloro-3-pyridyl)- methylamine IM-1-4 (Acetamiprid 

Metabolite): Soil Adsorption/Desorption Study: Lab Project Number: EC-97-382: F97525-001: 

RP397ACL. Unpublished study prepared by Rhone-Poulenc Ag Company. 168 p. 

44651886 Morgenroth, U. (1997) (Carbon 14)-NI-25: Leaching Characteristics of Aged Residues in One Soil: Lab 

Project Number: 374005. Unpublished study prepared by RCC Umweltchemie Ag. 95 p. 

46255604 Simmonds, M. (2003) (Carbon 14) - Acetamiprid: Aged Residue Column Leaching Study in Two 

Calcareous Soils. Project Number: CX/02/018, CX02018. Unpublished study prepared by Battelle 

Agrifood, Ltd. 159 p. 

Terrestrial field dissipation 

44988514 Norris, F. (1999) Acetamiprid: Terrestrial Soil Dissipation of Acetamiprid Following Applications of 

EXP 80667A 70WP to Ornamental Crops: Lab Project Number: 45752: 97512637. Unpublished study 

prepared by Rhone-Poulenc Ag Co. and Agvise, Inc. 798 p. 

44988515 Norris, F. (1999) Acetamiprid: Terrestrial Soil Dissipation of Acetamiprid (EXP 80667A) Under 

Agricultural Field Conditions Crops: Lab Project Number: 45753: 975126643: 12643-06. Unpublished 

study prepared by Rhone-Poulenc Ag Co. and ACDS Research, Inc. 788 p. 

44988516 Yang, J. (1999) Method Validation Report for Acetamiprid (NI-25): Performance Summary of Methods 

of Analysis for NI-25 and its Metabolites IC-0, IM-1-4, and IM-1-2 in US Soil Using LC/MS/MS: Lab 

Project Number: 45841: 45453: 9752643. Unpublished study prepared by Rhone-Poulenc Ag Co. 572 p. 

OPPTS 850.7100 

44988517 Zheng, S. (1999) Independent Laboratory Validation of Analytical Methods NI-25: Method of Analysis 

and its Metabolite, IC-0, Using LC/MS/MS; NI-25: Methods of Analysis for IM-1-2 a Metabolite of NI25 in Soil Using LC/MS/MS; and NI-25: Method of Analysis for IM-1-4, a Metabolite of NI-25, in Soil 

Using LC/MS/MS: Lab Project Number: 019-016: 98P-019-016: EC-98-447. Unpublished study 

prepared by Centre Analytical Labs., Inc. 152 p. OPPTS 850.7100 
112 

44988625 Cosgrove, D. (1999) A Terrestrial Field Dissipation Study with Acetamiprid, Canada, 1999: Final Study 

Report: Lab Project Number: 99086DC: 99001: 99002. Unpublished study prepared by Enviro-Test 

Lab., Inc. 388 p. 

Confined rotational crop 

44988623 Mislankar, S.; Mackie, S. (1999) (Carbon-14)-Acetamiprid: Foliar Treatment Confined Accumulation 

Study in Rotational Crops: Lab Project Number: EC-97-368. Unpublished study prepared by American 

Agricultural Services, Inc. and Agvise Labs. 345 p. OPPTS 860.1850 

General Considerations for efficacy of invertebrate control agents 

47536601 Smitley, D.; Davis, T.; Newhouse, K. (2007) Acetamiprid: Emerald Ash Borer Tree Trunk Injections 

and Sprays. Project Number: NAI/08/001. Unpublished study prepared by Michigan State University. 13 

p. 

47558701 Newhouse, K.; Smitley, D.; Davis, T. (2007) Acetamiprid: Emerald Ash Borer Tree Trunk Injections 

and Sprays; Amendment to MRID 47536601. Project Number: NAI/08/001/01. Unpublished study 

prepared by Michigan State University. 15 p. 

Dissociation constants in water 

46255602 Takashima, K. (2002) Dissociation Constant of IM-1-5. Project Number: NCAS/02/132. Unpublished 

study prepared by Nisso Chemical Analysis Service Co., Ltd. 18 p. 

Photodegradation of parent and degradates in soil 

48563501 Sugiyama, K. (2011) Photodegradation of [(Carbon 14)] Acetamiprid on Soil by Artificial Sunlight. 

Project Number: 2126W. Unpublished study prepared by PTRL West, Inc. 235p. 

Aerobic soil metabolism 

46255603 Simmonds, M. (2002) (Carbon 14)-Acetamiprid: Rate of Degradation in Three Calcareous Soils at 20 

(Degrees) C. Project Number: CX/01/013. Unpublished study prepared by Battelle Agrifood, Ltd. 198 p. 

Anaerobic soil metabolism 

48554501 Hiler, T. (2011) (Acetamiprid Technical): Anaerobic Soil Metabolism of Carbon 14 Acetamiprid on 

Two Soil Types. Project Number: 2105W, 2111W. Unpublished study prepared by PTRL West, Inc. 

170p. 

Non-Guideline Study 

44651801 Davis, E.; Davis, W. (1998) Reduced Risk and OP Replacement Rationale for Acetamiprid: Lab Project 

Number: RPAG-NI-25-98. Unpublished study prepared by Rhone Poulenc Ag Company. 148 p. 

44651818 Morishima, Y. (1997) NI-25 (PAI)--Spectra (UV/VIS, IR, NMR, MS) of NI-25: Lab Project Number: 2-

9713: PTL 2-9713. Unpublished study prepared by Nippon Soda Co., Ltd. 20 p. OPPTS 830.7050 

44651878 Higashida, S. (1998) Stability of IM-1-5 in Water: Lab Project Number: NCAS 98-012NG. Unpublished 

study prepared by Nisso Chemical Analysis Service Co., Ltd. 16 p. 

44988401 Christian, M.; Cunny, H.; Davis, W. et al. (1999) Reduced Risk and Organophosphate Replacement 

Rationale for Acetamiprid-Agricultural Uses: Lab Project Number: RR/09/CROP-1. Unpublished study 
113 

prepared by Rhone-Poulenc Ag Company. 370 p. 

44988402 Cunny, H.; Davis, E.; Davis, W. et al. (1999) Reduced Risk and Organophosphate Replacement 

Rationale for Acetamiprid-Ornamental and Home Garden Uses: Lab Project Number: RR/OP/ORN-2. 

Unpublished study prepared by Rhone-Poulenc Ag Company. 258 p. 

44988403 Cunny, H.; Davis, W.; Heintzelman, R. et al. (1999) Acetamiprid: OECD Tier II and Tier III Summary 

and Assessment of the Active Substance and Formulations, Documents M and N: Lab Project Number: 

111599. Unpublished study prepared by Rhone-Poulenc Ag Company. 559 p. 

44988405 Phillips, J. (1999) Exposure Estimates and Risk Assessment for Acetamiprid. Unpublished study 

prepared by Rhone Poulenc Ag Company. 20 p. 

44988412 Johnson, A. (1994) NI-25: Acute Toxicity to the Earthworm (Eisenia foetida): Lab Project Number: NPS 

63/932526. Unpublished study prepared by Huntingdon Research Centre Ltd. 22 p. 

44988536 Tokieda, M. (1997) Analytical Method for the Determination of Acetamiprid in Water (Validation 

Study): Lab Project Number: NCAS97-007: 171-4B. Unpublished study prepared by Nisso Chemical 

Analysis Service Co., Ltd. 68 p. OPPTS 860.1400 

45039702 Yang, J. (1999) Stability of Acetamiprid and Its Metabolites in Soil During Prolonged Freezer Storage: 

Lab Project Number: 97512642: 45754. Unpublished study prepared by Rhone-Poulenc Ag Company. 

299 p. OPPTS 860.1380 

45900500 Nippon Soda Co., Ltd (2003) Submission of Reduced-Risk, Residue, Risk, and Exposure Data in 

Support of the Amended Registrations of Acetamiprid Technical and Assail 70WP Insecticide and the 

Petition for Tolerance of Acetamiprid on Tuberous and Corn Vegetables Crop Group and Tobacco. 

Transmittal of 9 Studies. 

45900501 Christian, M.; Cunny, H.; Heintzelman, R.; et al. Reduced-Risk Pesticide Rationale for Acetamiprid: 

Lab Project Number: ACET-RR-01. Unpublished Study. 138 p. 

45900502 Christian, M. (2003) Reduced-Risk Pesticide Rationale for Acetamiprid: Lab Project Number: ACETRR-02. Unpublished Study. 4 p. 

45900503 Yang, H.; Werner, G. (2003) Reduced-Risk Pesticide Rationale for Acetamiprid: Lab Project Number: 

ACET-RR-03. Unpublished Study. 15 p. 

45921400 Nippon Soda Co., Ltd. (2003) Submission of Fate Data in Support of FIFRA 6(a)(2) Data Requirements 

for Assail 70 WP Insecticide. Transmittal of 1 Study. 

46056901 Li, K. (2003) Acetamiprid Exposure and Risk Assessment: Uses on General Household Pests. 

Unpublished study prepared by FMC Corporation. 22 p. 

46056902 Li, K. (2003) Acetamiprid Exposure and Risk Assessment: Termiticide Uses. Unpublished study 

prepared by FMC Corporation. 13 p. 

46093700 Gowan Company (2003) Submission of Efficacy Data in Support of the Reregistration of Phosmet. 

Transmittal of 2 Studies. 

46093701 Brunner, J. (2001) Control of the Codling Moth with Acetamiprid (Assail) and Phosmet (Imidan), 2001. 

Project Number: IMI/102/01. Unpublished study prepared by Washington State University. 6 p. 

46229601 Sances, F. (2003) Evaluation of Assail 70 W for Negative Effects on Lettuce. Project Number: 

NAI/04/001. Unpublished study prepared by Pacific Agricultural Research Corp. 97 p. 

46229602 Sances, F. (2003) Addendum Report: Evaluation of Assail 70 W for Negative Effects on Head Lettuce, 

Butter Varieties. Project Number: NAI/04/002. Unpublished study prepared by Pacific Agricultural 

Research Corp. 82 p. 
114 

46255600 Nippon Soda Co., Ltd. (2004) Submission of Risk/Exposure, Fate, Toxicity and Efficacy Data in 

Support of the Amended Registrations of Acetamiprid Technical and ASSAIL 70 WP Insecticide and 

the Petition for Tolerance of Acetamiprid on Curcurbits, Stone Fruit and Tree Nut Crop Groups. 

Transmittal of 19 Studies. 

46255605 Kawai, H.; Fujii, Y.; Saika, O.; et. al. (2003) Position Statement on Persistence and Mobility of IM-1-5 

in Soil. Project Number: NAI/04/003. Unpublished study prepared by Nippon Soda Co Ltd. 74 p. 

46255607 Kawai, H. (2003) Position Paper: IM-1-4, Persistence in Sediment. Project Number: RD/03199. 

Unpublished study prepared by Nippon Soda Co Ltd. 9 p. 

46255609 Putt, A. (2003) IM-1-5: Full Life-Cycle Toxicity Test with Water Fleas, Daphnia magna, Under StaticRenewal Conditions. Project Number: 13798/6112. Unpublished study prepared by Springborn Smithers 

Laboratories. 62 p. 

46255610 Putt, A. (2003) IM-1-5: Acute Toxicity to Midge (Chironomus riparius) Under Static Conditions. Project 

Number: 13798/6111. Unpublished study prepared by Springborn Laboratories Inc. 48 p. 

46255611 Schmitzer, S. (2003) Effects of IM-1-5 on Reproduction of Rove Beetles Aleochara bilineata in the 

Laboratory: (Final Report). Project Number: 15722070. Unpublished study prepared by Institut fuer 

Biologische Analytik und Consulting IBACON GmbH. 30 p. 

46255612 Klein, S. (2003) Effects of IM-1-5 on Reproduction of the Collembola Folsomia candida in Artificial 

Soil. Project Number: 15721016, C029622. Unpublished study prepared by Institut fuer Biologische 

Analytik Und Consulting IBACON GmbH. 27 p. 

46255613 Rodgers, M. (2002) IM-1-5: Acute Toxicity (LC50) to the Earthworm. Project Number: 

NOD/217/024192. Unpublished study prepared by Huntingdon Life Sciences, Ltd. 17 p. 

46255614 Luhrs, U. (2003) Effects of IM-1-5 on Reproduction and Growth of Earthworms Eisenia fetida in 

Artificial Soil. Project Number: 15723022. Unpublished study prepared by Institut fuer Biologische 

Analytik Und Consulting IBACON GmbH. 33 p. 

46255615 Hatano, R. (2002) Insecticidal Activities of Acetamiprid Metabolites: IM-1-5 and IM-1-5-HCL. Project 

Number: NAI/04/004. Unpublished study prepared by Nippon Soda Co., Ltd. 7 p. 

46255620 Fujii, Y. (2002) Acetamiprid Suspended in Corn Oil: Acute Oral Toxicity Study in Rats. Project 

Number: H221. Unpublished study prepared by Nippon Soda Co., Ltd. 33 p. 

46255621 Fujii, Y. (2002) IM-1-5: Acute Oral Toxicity Study in Rats. Project Number: H220. Unpublished study 

prepared by Nippon Soda Co., Ltd. 30 p. 

46255622 Saito, H. (2002) Metabolism Study of Acetamiprid in Rat (Determination of IM-1-5). Project Number: 

NSM/02/024. Unpublished study prepared by Nippon Soda Co., Ltd. 112 p. 

47523404 Iwasa, T.; Motoyama, N.; Ambrose, J.; et al. (2003) Mechanism for the Differential Toxicity of 

Neonicotinoid Insecticides in the Honey Bee, Apis mellifera. Crop Protection 23(2004): 371-378. 

47800502 Nauen, R.; Ebbinghaus-Kintscher, U.; Schmuck, R. (2001) Toxicity and Nicotinic Acetylcholine 

Receptor Interaction of Imidacloprid and its Metabolites in Apis mellifera (Hymenoptera: Apidae). Pest 

Management Science 57(7):577-586. 

47800507 Aliouane, Y.; el Hassani, A.; Gary, V.; et al. (2009) Subchronic Exposure of Honeybees to Sublethal 

Doses of Pesticides: Effects on Behavior. Environmental Toxicology and Chemistry 28(1):113-122. 

47800509 Guez, D; Belzunces, L. P.; Maleszka, R. (2003) Effects of Imidacloprid Metabolites on Habituation in 

Honeybees Suggest the Existence of Two Subtypes of Nicotinic Receptors Differentially Expressed 

during Adult Development. Pharmacology, Biochemistry, and Behavior 75:217-222. 
115 

47838500 Nippon Soda Co., Ltd. (2009) Submission of Product Chemistry and Toxicity Data in Support of the 

Application for Registration of Acetamiprid Concentrate Insecticide. Transmittal of 10 Studies. 

47848100 Nippon Soda Co., Ltd. (2009) Submission of Product Chemistry and Toxicity Data in Support of the 

Application for Registration of Acetamiprid + Triticonazole Concentrate. Transmittal of 9 Studies. 

48498301 Laurino, D.; Porporato, M.; Patetta, A.; et al. (2011) Toxicity of Neonicotinoid Insecticides to Honey 

Bees: Laboratory Tests. Bulletin of Insectology 64(1): 107-113. 

48499800 Interregional Research Project No. 4 (2011) Submission of Pesticide Use Data in Support of the 

Proposed New Crop Group 24 - Stalk, Stem and Leafy Petiole. Transmittal of 1 Study. 
116 

Appendix A. Supplemental Environmental Fate Information 

Table A1. Structures of Acetamiprid and Its Environmental Transformation Products. 

Code Name/ Synonym/ 

Chemical Name/ Formula/MW/ SMILES Chemical Structure 

Acetamiprid 

IUPAC: (E)-N1

-[(6-chloro-3-pyridyl)methyl]-N2-cyanoN

1

-methyl 

CAS: (1E)-N-[(6-chloro-3-pyridinyl)methyl]-N'-cyano-Nmethylethanimidamide 

CAS No.: 135410-20-7 

Formula: C16H11CLN4

MW: 222.68 g/mol 

SMILES: Clc1ncc(cc1)CN(\C(=N\C#N)C)C

IM-1-2 

IUPAC: N2

-carbamoyl-N1-[(6-chloro-3-pyridyl)methyl]-

N1

-methylacetamidine

 

Formula: C10H13ClN4O 

MW: 240.69 g/mol 

SMILES: C/C(=N\C(=O)N)/N(C)Cc1ccc(nc1)Cl

IM-1-3

IUPAC: N-[(6-chloro-3-pyridyl)methyl]-Nmethylacetamide

 

Formula: C9H11ClN2O 

MW: 198.65 g/mol 

SMILES: CC(=O)N(C)Cc1ccc(nc1)Cl

IM-1-4 

IUPAC: N-methyl(6-chloro-3-pyridyl)methylamine 

MW: 155.5 g/mole 

SMILES: C1=C(C=CC(=C1)CN(C)[H])Cl 
117 

Code Name/ Synonym/ 

Chemical Name/ Formula/MW/ SMILES Chemical Structure 

IM-1-5

IUPAC: (E)-N1-[(6-chloro-3-pyridyl)-methyl]-N2-

cyano-N1-methylacetamidine 

SMILES: C1=CC(=NC=C1CN(C)C(C)=N)Cl

N Cl

N

NH

IC-0 

IUPAC: 6-Chloronicotinic acid

 

Formula: C6H4ClNO2

MW: 157.55 g/mol 

SMILES: c1cc(ncc1C(=O)O)Cl

IM-0 

IUPAC: (6-Chloro-3-pyridyl)methanol

 

Formula: C6H6ClNO 

MW: 143.57 g/mol 

SMILES: c1cc(ncc1CO)Cl

IM-2-1 

IUPAC: N1

-[(6-chloro-3-pyridyl)methyl]-N2-

cyanoacetamidine

 

Formula: C9H9ClN4

MW: 208.65 g/mol 

SMILES: C/C(=N\C#N)/NCc1ccc(nc1)Cl

IM-2-3 

IUPAC: N-[(6-chloro-3-pyridyl)methyl]acetamide

 

Formula: C8H9ClN2O 

MW: 184.62 g/mol 

SMILES: CC(=O)NCc1ccc(nc1)Cl

Abbreviations MW =molecular weight; IUPAC: International Union of Pure and Applied Chemistry name; 

SMILES: Simplified Molecular-input Line-entry System 

 
118 

Table A2. Maximum amount of applied radioactivity present as a specified compound in 

environmental fate studies submitted on acetamiprid.

Compound 

Max %AR 

(Sampling 

Interval) 

Final %AR 

(Sampling 

Interval) 

Comment Study Type MRID 

Acetamiprid Not Applicable 95 (35 days) pH 4 all temps Hydrolysis 44651876 

97. (35 days) pH 5 all temps Hydrolysis 44651876 

93 (35 days) pH 7 all temps Hydrolysis 44651876 

88 (35 days) pH 9 all temps Hydrolysis 44651876 

54 (30 days) Water Aqueous Photolysis 44688509 

27 (24 days) Loamy sand Soil Photolysis 48563501 

1 (187 days) Sandy Loam 01/07 Aerobic Soil 46255603 

1 (187 days) Clay loam 01/08 Aerobic Soil 46255603 

1 (187 days) Clay loam 01/10 Aerobic Soil 46255603 

<1 (112 days) Collumbey soil Aerobic Soil 44699101 

<1 (365 days) Loamy sand Aerobic Soil 44651879 

nd (7 days) Sandy Loam Aerobic Soil 44651880 

46 (182 days) Clay loam, 20oC Aerobic Soil 44651881 

3 (182 days) Sandy loam, 20oC Aerobic Soil 44651881 

<1 (182 days) Silty clay loam, 20oC Aerobic Soil 44651881 

4 (178 days) Clay loam, 10oC Aerobic Soil 44651881 

2 (125 days) Sandy loam Anaerobic Soil 48554501 

17 (127 days) Clay loam Anaerobic Soil 48554501 

5 (300 days) Sandy loam Aerobic Aquatic 44988513 

52 (365 days) Loamy sand Anaerobic Aquatic 44988512 

IM-1-4 <1 (0 days) <1 (35 days) pH 4 all temps Hydrolysis 44651876 

<1 (0 days) <1 (35 days) pH 5 all temps Hydrolysis 44651876 

<1 (35 days) <1 (35 days) pH 7 all temps Hydrolysis 44651876 

15 (35 days) 15 (35 days) pH 9 all temps Hydrolysis 44651876 

nd nd Water Aqueous Photolysis 44688509 

32 (24 d) 32 (24 d) Loamy sand Soil Photolysis 48563501 

21 (7 days) 1 (187 days) Sandy Loam 01/07 Aerobic Soil 46255603 

21 (7 days) <1 (187 days) Clay loam 01/08 Aerobic Soil 46255603 

18 (7 days) 1 (187 days) Clay loam 01/10 Aerobic Soil 46255603 

61 (7 days) 26 (112 days) Collumbey soil Aerobic Soil 44699101 

73 (120 days) 61 (365 days) Loamy sand Aerobic Soil 44651879 

16 (7 days) 16 (7 days) Sandy Loam Aerobic Soil 44651880 

56 (14 days) 37 (182 days) Clay loam, 20oC Aerobic Soil 44651881 

73 (14 days) 42 (182 days) Sandy loam, 20oC Aerobic Soil 44651881 

67 (3 days) 1 (182 days) Silty clay loam, 20oC Aerobic Soil 44651881 

73 (30 days) 54 (178 days) Clay loam, 10oC Aerobic Soil 44651881 

64 (61 days) 61 (125 days) Sandy loam Anaerobic Soil 48554501 

49 (93 days) 46 (127 days) Clay loam Anaerobic Soil 48554501 

64 (60 days) 34 (300 days) Sandy loam Aerobic Aquatic 44988513 

27 (270 days) 27 (270 days) Loamy sand Anaerobic Aquatic 44988512 

IM-1-5 na na pH 4 all temps Hydrolysis 44651876 

na na pH 5 all temps Hydrolysis 44651876 
119 

Compound 

Max %AR 

(Sampling 

Interval) 

Final %AR 

(Sampling 

Interval) 

Comment Study Type MRID 

na na pH 7 all temps Hydrolysis 44651876 

na na pH 9 all temps Hydrolysis 44651876 

nd nd Water Aqueous Photolysis 44688509 

na na Loamy sand Soil Photolysis 48563501

16 (187 days) 16 (187 days) Sandy Loam 01/07 Aerobic Soil 46255603 

12 (187 days) 12 (187 days) Clay loam 01/08 Aerobic Soil 46255603 

13 (7 days) 8 (187 days) Clay loam 01/10 Aerobic Soil 46255603 

na na Collumbey soil Aerobic Soil 44699101 

na na Loamy sand Aerobic Soil 44651879 

na na Sandy Loam Aerobic Soil 44651880 

na na Clay loam, 20oC Aerobic Soil 44651881 

nd nd Sandy loam, 20oC Aerobic Soil 44651881 

22 (13 days) 13 (182 days) Silty clay loam, 20oC Aerobic Soil 44651881 

nd nd Clay loam, 10oC Aerobic Soil 44651881 

na na Sandy loam Anaerobic Soil 48554501 

na na Clay loam Anaerobic Soil 48554501 

na na Sandy loam sediment Aerobic Aquatic 44988513 

na na Loamy sand sediment Anaerobic Aquatic 44988512 

IC-0 na na pH 4 all temps Hydrolysis 44651876 

na na pH 5 all temps Hydrolysis 44651876 

na na pH 7 all temps Hydrolysis 44651876 

na na pH 9 all temps Hydrolysis 44651876 

nd nd Water Aqueous Photolysis 44688509 

16 (24 days) 16 (24 days) Loamy sand Soil Photolysis 48563501 

5.2 (7 days) nd (187 days) Sandy Loam 01/07 Aerobic Soil 46255603 

7 (7 days) nd (187 days) Clay loam 01/08 Aerobic Soil 46255603 

10 (7 days) nd (187 days) Clay loam 01/10 Aerobic Soil 46255603 

11 (4 days) 1 (112 days) Collumbey soil Aerobic Soil 44699101 

5 (60 days) 3 (365 days) Loamy sand Aerobic Soil 44651879 

11 (2 days) 10 (7 days) Collumbey Sandy Aerobic Soil 44651880 

11 (120 days) 4 (182 days) Clay loam, 20oC Aerobic Soil 44651881 

4 (120 days) 3 (182 days) Sandy loam, 20oC Aerobic Soil 44651881 

12 (7 days) nd (182 days) Silty clay loam, 20oC Aerobic Soil 44651881 

3 (178 days) 3 (178 days) Clay loam, 10oC Aerobic Soil 44651881 

3 (125 days) 3 (125 days) Sandy loam Anaerobic Soil 48554501 

1 (127 days) 1 (127 days) Clay loam Anaerobic Soil 48554501 

19 (180 days) nd (300 days) Sandy loam sediment Aerobic Aquatic 44988513 

nd nd (187 days) Loamy sand sediment Anaerobic Aquatic 44988512 

IM-1-2 na na pH 4 all temps Hydrolysis 44651876 

na na pH 5 all temps Hydrolysis 44651876 

na na pH 7 all temps Hydrolysis 44651876 

na na pH 9 all temps Hydrolysis 44651876 

nd nd Water Aqueous Photolysis 44688509 

0.7 (7 d) nd (24 d) Loamy sand Soil Photolysis 48563501 

36 (1 day) nd (187 days) Sandy Loam 01/07 Aerobic Soil 46255603 
120 

Compound 

Max %AR 

(Sampling 

Interval) 

Final %AR 

(Sampling 

Interval) 

Comment Study Type MRID 

29 (3 days) nd (187 days) Clay loam 01/08 Aerobic Soil 46255603 

28 (1 days) nd (187 days) Clay loam 01/10 Aerobic Soil 46255603 

8 (1 day) nd (112 days) Collumbey soil Aerobic Soil 44699101 

nd nd Loamy sand Aerobic Soil 44651879 

55 (1 day) nd (7 day) Collumbey Sandy Aerobic Soil 44651880 

<LOQ (2 days) nd (182 days) Clay loam, 20oC Aerobic Soil 44651881 

nd nd Sandy loam, 20oC Aerobic Soil 44651881 

<LOQ (1 day) nd (182 days) Silty clay loam, 20oC Aerobic Soil 44651881 

<LOQ (2 days) nd (182 days) Clay loam, 10oC Aerobic Soil 44651881 

4 (5 days) Nd (125 days) Sandy loam Anaerobic Soil 48554501 

3 (7 days) Nd (127 days) Clay loam Anaerobic Soil 48554501 

21 (30 days) 0.74 (300 days) Sandy loam sediment Aerobic Aquatic 44988513 

1 (90 days) nd (365 days) Loamy sand sediment Anaerobic Aquatic 44988512 

IM-0 na na pH 4 all temps Hydrolysis 44651876 

na na pH 5 all temps Hydrolysis 44651876 

na na pH 7 all temps Hydrolysis 44651876 

na na pH 9 all temps Hydrolysis 44651876 

nd nd Water Aqueous Photolysis 44688509 

nd nd Loamy sand Soil Photolysis 48563501 

nd nd Sandy Loam 01/07 Aerobic Soil 46255603 

2.21 (7 days) nd (187 days) Clay loam 01/08 Aerobic Soil 46255603 

1 (14 days) nd (187 days) Clay loam 01/10 Aerobic Soil 46255603 

na na Collumbey soil Aerobic Soil 44699101 

na na Loamy sand Aerobic Soil 44651879 

na na Collumbey Sandy Aerobic Soil 44651880 

na na Clay loam, 20oC Aerobic Soil 44651881 

na na Sandy loam, 20oC Aerobic Soil 44651881 

na na Silty clay loam, 20oC Aerobic Soil 44651881 

na na Clay loam, 10oC Aerobic Soil 44651881 

2 (1 day) nd (125 days) Sandy loam Anaerobic Soil 48554501 

nd nd Clay loam Anaerobic Soil 48554501 

na na Sandy loam sediment Aerobic Aquatic 44988513 

na na Loamy sand sediment Anaerobic Aquatic 44988512 

IM-1-3 <1 (15 days) <1 (35 days) pH 4 all temps Hydrolysis 44651876 

<1 (35 days) <1 (35 days) pH 5 all temps Hydrolysis 44651876 

4 (22 days) 4 (35 days) pH 7 all temps Hydrolysis 44651876 

61 (35 days) 61 (35 days) pH 9 all temps Hydrolysis 44651876 

nd nd Water Aqueous Photolysis 44688509 

4 (24 days) 4 (24 days) Loamy sand Soil Photolysis 48563501 

nd nd Sandy Loam 01/07 Aerobic Soil 46255603 

3 (7 days) nd (187 days) Clay loam 01/08 Aerobic Soil 46255603 

2 (7 days) nd (187 days) Clay loam 01/10 Aerobic Soil 46255603 

3 (4 days) nd (112 days) Collumbey soil Aerobic Soil 44699101 

3 (60 days) <1 (365 days) Loamy sand Aerobic Soil 44651879 

nd nd (7 days) Collumbey Sandy Aerobic Soil 44651880 
121 

Compound 

Max %AR 

(Sampling 

Interval) 

Final %AR 

(Sampling 

Interval) 

Comment Study Type MRID 

3 (28 days) <1 (182 days) Clay loam, 20oC Aerobic Soil 44651881 

<LOQ (14 days) <LOQ (14 days) Sandy loam, 20oC Aerobic Soil 44651881 

2 (7 days) 0.71 (182 days) Silty clay loam, 20oC Aerobic Soil 44651881 

2 (122 days) 2 (122 days) Clay loam, 10oC Aerobic Soil 44651881 

3 (5 days) 3 (125 days) Sandy loam Anaerobic Soil 48554501 

2 (24-127 days) 2 (127 days) Clay loam Anaerobic Soil 48554501 

1 (90 days) nd (300 days) Sandy loam sediment Aerobic Aquatic 44988513 

8 (180 days) 6 (365 days) Loamy sand sediment Anaerobic Aquatic 44988512 

IM-2-1 3 (17 days) 2 (24 days) Loamy sand Soil Photolysis 48563501 

nd nd Sandy loam Anaerobic Soil 48554501 

nd nd Clay loam Anaerobic Soil 48554501 

IM-2-3 nd nd Loamy sand Soil Photolysis 48563501 

2 (5 days) nd (125days) Sandy loam Anaerobic Soil 48554501 

1 (11 days) nd (127 days) Clay loam Anaerobic Soil 48554501 

Unidentified 

Compound 

3 (14 days) nd (187 days) Sandy Loam 01/07 Aerobic Soil 46255603 

1 (14 days) nd (187 days) Clay loam 01/08 Aerobic Soil 46255603 

4 (187 days) 4 (187 days) Clay loam 01/10 Aerobic Soil 46255603 

4 (4 days) nd (112 days) Collumbey soil Aerobic Soil 44699101 

2 (3 days) nd (365 days) Loamy sand Aerobic Soil 44651879 

12 (7 days) 12 (7 days) Collumbey Sandy Aerobic Soil 44651880 

3 (56 days) 2 (182 days) Clay loam, 20oC Aerobic Soil 44651881 

<1 (56 days) <1 (56 days) Sandy loam, 20oC Aerobic Soil 44651881 

<1 (7 days) nd (182 days) Silty clay loam, 20oC Aerobic Soil 44651881 

<1 (182 days) <1 (182 days) Clay loam, 10oC Aerobic Soil 44651881 

Unextracted 

Residues 

26 (118 days) 19 (187 days) Sandy Loam 01/07 Aerobic Soil 46255603 

31 (28 days) 20 (187 days) Clay loam 01/08 Aerobic Soil 46255603 

29 (14 days) 28 (187 days) Clay loam 01/10 Aerobic Soil 46255603 

16 (112 days) 16 (112 days) Collumbey soil Aerobic Soil 44699101 

21 (365 days) 21 (365 days) Loamy sand Aerobic Soil 44651879 

14 (7 days) 14 (7 days) Collumbey Sandy Aerobic Soil 44651880 

40 (182 days) 40 (182 days) Clay loam, 20oC Aerobic Soil 44651881 

26 (182 days) 26 (182 days) Sandy loam, 20oC Aerobic Soil 44651881 

21 (28 days) 18 (182 days) Silty clay loam, 20oC Aerobic Soil 44651881 

25 (178 days) 25 (178 days) Clay loam, 10oC Aerobic Soil 44651881 

31 (91 days) 30 (125 days) Sandy loam Anaerobic Soil 48554501 

42 (93 days) 36 (127 days) Clay loam Anaerobic Soil 48554501 

38 (300 days) 38 (300 days) Sandy loam sediment Aerobic Aquatic 44988513 

17 (270 days) 17 (365 days) Loamy sand sediment Anaerobic Aquatic 44988512 

CO2 3 (16-24 days) 3 (24 days) Loamy sand Soil Photolysis 48563501 

52 (118 days) 50 (187 days) Sandy Loam 01/07 Aerobic Soil 46255603 

54 (91 days) 54 (187 days) Clay loam 01/08 Aerobic Soil 46255603 

57 (118 days) 51 (187 days) Clay loam 01/10 Aerobic Soil 46255603 

<1 (30 days) <1 (30 days) Water Aqueous photolysis 44688509 

56 (112 days) 56 (112 days) Collumbey soil Aerobic Soil 44699101 

19 (270 days) 12 (365 days) Loamy sand Aerobic Soil 44651879 
122 

Compound 

Max %AR 

(Sampling 

Interval) 

Final %AR 

(Sampling 

Interval) 

Comment Study Type MRID 

44 (7 days) 44 (7 days) Collumbey Sandy Aerobic Soil 44651880 

1 (9 days) 0.3 (125 days) Sandy loam Anaerobic Soil 48554501 

0.6 (3 days) 0.4 (127 days) Clay loam Anaerobic Soil 48554501 

5 (300 days 5 (300 days) Sandy loam Aerobic Aquatic 44988513 

1 (365 days) 1 (365 days) Loamy sand sediment Anaerobic Aquatic 44988512 

na=not analyzed; nd=not detected; AR=applied radioactivity 

If a study is not listed under a specific analyte, it was not analyzed in the study. 
123 

Table A3. Summary of environmental fate and transport properties of IC-0 (6-chloronicotinic acid), a deg

acetamiprid 

Parameter Value(s) Source Study 

Classification

Comment 

Aerobic Soil 

Metabolism Halflife

Half-life, linear regression1: 

2.5 days (sandy loam soil at 20oC) 

1.7 days (clay soil at 20oC) 

6.6 days (loam soil at 20oC) 

MRID 

44651882 Supplemental British soils and USDA classificat

determined. Unextracted residues r

20.7% of applied radioactivity. Hal

using a subset of data for clay an

Solid-water 

distribution 

coefficient (Kd) 

Average Kd in L/kg at 20oC: 

0.44, loamy sand, pH 4.4 0.83, loam sand II, pH 6.2 0.28, silt loam, pH 6.6 0.28, clay, pH 7.5 2.36, sandy loam sediment, pH 5.6 

MRID 

44651884 Acceptable 

Freundlich solidwater distribution 

coefficient (KF) 

K F in L/kg (1/n) at 20oC: 

0.40 (0.91), loamy sand, pH 4.4 0.79 (1.0), loam sand II, pH 6.2 0.26 (0.94), silt loam, pH 6.6 0.19 (0.82), clay, pH 7.5 1.81 (0.86), sandy loam sediment, pH 5.6 

MRID 

44651884 Acceptable Freundlich exponents indicate tha

dependent on concentration in 

Organic-carbon 

normalized 

distribution 

coefficient (KOC) 

Average KOC in L/kg OC at 20oC: 

177, loamy sand, pH 4.4 56, loam sand II, pH 6.2 64, silt loam, pH 6.6 34, clay, pH 7.5 94, sandy loam sediment, pH 5.6 

MRID 

44651884 Acceptable None 
124 

Appendix B. Summary of Available Effects Studies 

Aquatic Organisms 

Tables B1 to B7 contain all available aquatic toxicity endpoints from registrant-submitted 

studies. Below is a brief summary of available aquatic toxicity studies. 

Fish and Aquatic-Phase Amphibians

Two acute toxicity studies (Table B1) have been submitted examining the effect of acetamiprid 

on freshwater fish. A 96-hr flow-through study with the bluegill sunfish (Lepomis macrochirus; 

MRID 44651863) was conducted at measured concentrations of 0 (control), 11.8, 20.0, 35.4, 

65.0 and 119.3 mg ai/L. No mortality was observed in any of the test concentrations with the 

LC50 >100 mg ai/L. Darkened body pigmentation was observed in all fish at all treatments, 

therefore the NOAEC for the study, based on alterations in fish coloration is <11.8 mg ai/L. A 

96-hr flow-through study was conducted with rainbow trout (Oncorhynchus mykiss; MRID 

44651864) at nominal concentrations of 0 (control), 25, 35, 50, 70 and 100 mg ai/L. Mortality 

was limited to 20% at the highest concentration, with the LC50>100 mg ai/L. However, sublethal 

effects, including darkened body pigmentation, swollen abdomen and loss of equilibrium were 

reported in 20% of the fish at both the 50 and 70 mg ai/L concentrations and 90% at the 100 mg 

ai/L concentration. The NOAEC for the study is 35 mg ai/L. Acetamiprid is classified as 

practically nontoxic to freshwater fish on an acute exposure basis, however sublethal effects 

were noted. 

A 96-hr static renewal acute exposure study of the effects of the degradate IM-1-4 on rainbow 

trout is available (MRID 44651865) (Table B1). The fish were exposed at measured 

concentrations of 4.3, 8.5, 16.9, 33.8, 69.3 and 98.1 mg ai/L. The 98.1 mg ai/L concentration 

was buffered and conducted separately after mortality of 100% was observed in the unbuffered 

69.3 mg ai/L concentration. The pH of the 69.3 mg ai/L replicates ranged from 9.0 to 9.3, which 

may account for the mortality. No mortalities were reported in the other concentrations. 

Sublethal effects, including darkened body pigmentation and surface swimming were observed 

in all concentrations above 4.3 mg ai/L (the NOAEC for the study). The LC50 is >98.1 mg ai/L; 

the degradate IM-1-4 is classified as practically nontoxic to freshwater fish on an acute exposure 

basis. 
125 

Table B1. Acute toxicity of technical grade acetamiprid and degradate IM-1-4 to 

freshwater fish.

Species Test 

substance

LC50 

mg ai/L Toxicity Category MRID Study 

Classification

Rainbow trout 

(Oncorhynchus mykiss) 

Technical 

acetamiprid >100 Practically 

non-toxic 44651864 Acceptable 

Bluegill sunfish 

(Lepomis macrochirus) 

Technical 

acetamiprid >100 Practically 

non-toxic 44651863 Acceptable 

Rainbow trout 

(Oncorhynchus mykiss) 

94.5% 

IM-1-4 

degradate 

>98.1 Practically 

non-toxic 44651865 Supplemental 

In a 96-h flow-through acute toxicity study (Table B2), estuarine/marine sheepshead minnows 

(Cyprinodon variegatus) were exposed to measured acetamiprid concentrations of 0 (control), 

19, 32, 54, 90 and 150 mg ai/L. Mortality was 10% in the 90 mg ai/L and 100% in the 150 mg 

ai/L test concentrations. Lethargy was observed in all of the surviving fish at the 90 mg ai/L 

treatment level. No other sublethal effects were reported. The 96-hr LC50 is 100 mg ai/L, which 

classifies acetamiprid as slightly toxic to estuarine/marine fish on an acute exposure basis. 

Table B2. Acute toxicity of technical grade acetamiprid to estuarine/marine fish.

Species Test 

Substance

LC50 

mg ai/L Toxicity Category MRID Study 

Classification

Sheepshead minnow 

(Cyprinodon 

variegatus)

Technical 

acetamiprid 100* Slightly toxic 44988411 Acceptable 

* Most sensitive endpoint 

A 35-day flow-through fish early life stage toxicity study (MRID 44651872) was submitted to 

evaluate the effect of chronic exposure on freshwater fish. Fathead minnow (Pimephales 

promelas) were exposed to acetamiprid at measured concentrations of 9.9, 19.2, 38.4, 76.0, and 

147.5 mg ai/L. Mortalities were reported at 5% 20% and 100% in concentrations 38.4, 76.0 and 

147.5 mg ai/L, respectively. Weights were reduced 17% and 62% at concentrations 38.4 and 

76.0 mg ai/L. The lowest observed adverse effect concentration (LOAEC) for the study is 38.4 

mg ai/L based on decreased survival and growth. The NOAEC is 19.2 mg ai/L (Table B3). 

No chronic toxicity data have been submitted for estuarine/marine fish. 

Table B3. Early life-stage toxicity of technical grade acetamiprid to freshwater fish.

Species Test 

Substance NOAEC LOAEC Endpoints Affected MRID Study Classification

Fathead 

minnow 

(Pimphales 

promelas)

Technical 

acetamiprid 

19.2 mg 

ai/L* 

38.4 mg 

ai/L 

Embryo and larval 

survival, larval 

growth (wet-weight 

and length) 

44651872 Supplemental 

* Most sensitive endpoint 
126 

Aquatic Invertebrates

An acute toxicity study was submitted to assess the effect of acetamiprid on the water flea 

(Daphnia magna; MRID 44651866) at nominal concentrations of 0 (control), 12.5, 25, 50, 100 

and 200 mg ai/L. Immobile daphnids were observed at 20%, 45%, 85% and 100% at 

concentrations of 25, 50, 100 and 200 mg ai/L. The LC50 for daphnids is 50 mg ai/L and the 

NOAEC, based on immobility, is 12.5 mg ai/L (Table B4). 

A 96-hr acute toxicity study (MRID 45932501) was submitted for the freshwater amphipod, 

Gammarus fasciatus. Test organisms were exposed at measured concentrations of 0 (control), 

9.4, 18, 33, 76 and 140 μg ai/L. Mortality was 5% in the control and 0, 10, 40, 35 and 70%, in 

the treatment groups respectively. Lethargy was observed at the 33 μg ai/L concentration and 

higher. The LC50 is 80 μg ai/L and the NOAEC is 18 μg ai/L based on lethargy. The slope of 

the dose-response curve is 1.89. Based on a 96-hr LC50 value of 80 μg ai/L, acetamiprid is 

classified as very highly toxic to freshwater invertebrates on an acute exposure basis. 

The 48-hour acute toxicity of acetamiprid (technical) to the midge, Chironomus riparius, was 

studied under static conditions (MRID 45916201). Test organisms were exposed to negative 

control, solvent (acetone) control and test chemical at a single dosing nominal concentrations of 

6.3, 13, 25, 50, and 100 μg/L (corresponding mean-measured concentrations were 6.0, 14, 26, 46 

and 110 μg ai/L) in overlying water. Mortality was recorded at 0, 24 and 48 hours. After 48 

hours of static exposure to acetamiprid in the presence of sediment, the 48-hr LC50 is 20.9 μg 

ai/L based on mean-measured concentrations. The NOAEC is 6 μg ai/L, based on mortality. 

An aquatic invertebrate study with acetamiprid was identified in the ECOTOX database 

(Beketov and Liess, 2008). In this study, amphipods (Gammarus pulex), blackfly larvae 

(Simulium latigonium), and mayfly larvae (Baetis rhodani) were exposed to as single 

concentration of acetamiprid for 96 hours under static conditions; LC50 values were subsequently 

determined. The results and scientific soundness of this study will be evaluated prior to endpoint 

selection for the upcoming acetamiprid registration review risk assessment. 

The 48-hr-acute toxicity of the IM-1-4 degradate to Daphnia magna was studied under static 

renewal conditions at mean measured concentrations of 6.9, 13.9, 28.0, 55.9 and 113.0 mg ai/L. 

The 48- hour EC50 was 43.9 mg ai/L. The NOAEC based on mortality/immobilization was 6.9 

mg ai/L. Based on the results of this study, IM-1-4 is classified as slightly toxic to Daphnia 

magna. Two other acute exposure studies evaluating the toxicity of acetamiprid degradates IC-0 

and IM-1-2 to daphnids are available, and resulted in EC50 values that were greater than the 

highest concentration tested; therefore, these degradates are classified as practically non-toxic to 

daphnids on an acute exposure basis. 

In a 48-hour static acute toxicity study, effects of the acetamiprid degradate IM-1-5 to the 

sediment-dwelling freshwater midge, Chironomus riparius, were assessed (MRID 46255610). 

Test organisms were exposed to mean-measured concentrations (in the overlying water) of 0 

(control), 6.0, 14, 26, 46 and 110 μg ai/L. The 48-hr LC50 is 68 mg ai/L based on meanmeasured concentrations. The NOAEC is 49 mg ai/L, based on mortality. The acetamiprid 

degradate IM-1-5 is classified as slightly toxic to freshwater invertebrates on an acute exposure 
127 

basis. 

Table B4. Acute toxicity of acetamiprid and degradates to freshwater invertebrates.

Species Test 

substance

EC50/LC50

mg ai/L 

Toxicity 

Category MRID Study Classification

Waterflea 

(Daphnia magna)

Technical 

acetamiprid 50 Slightly toxic 44651866 Supplemental 

Amphipod 

(Gammarus fasciatus)

Technical 

acetamiprid 0.08 Very highly 

toxic 45932501 Supplemental 

Midge 

(Chironomus riparius) 

Technical 

acetamiprid 0.021* Very highly toxic 45916201 Supplemental 

Waterflea 

(Daphnia magna)

99.7% IC-0 

degradate >95.1 Practically nontoxic 44988409 Acceptable 

Waterflea 

(Daphnia magna)

99.6%IM-1-2 

degradate >99.8 Practically nontoxic 44651867 Acceptable 

Waterflea 

(Daphnia magna)

98.7% IM-1-4 

degradate 43.9 Slightly toxic 44651868 Acceptable 

Midge 

(Chironomus riparius) 

98.9% IM-1-5 

degradate 68 Slightly toxic 46255610 Acceptable 

* Most sensitive endpoint 

In a 96-hr acute flow-through toxicity study, mysid shrimp (Americamysis bahia) were exposed 

to mean measured concentrations of 0 (control), 13, 23, 36, 64 and 110 μg ai/L. Mortality was 

5%, 10% and 35% and 90% in the 23, 36, 64 and 110 μg ai/L treatment levels respectively. 

Lethargy was reported in all of the surviving mysids exposed to the 64 and 110 μg ai/L treatment 

levels. The LC50 is 66 μg ai/L and the NOAEC is 13 μg ai/L based on lethargy; acetamiprid is 

classified as very highly toxic to mysid shrimp on an acute exposure basis (Table B5). 

In a 96-hr-acute flow-through toxicity study, Eastern oysters (Crassostrea virginica) were 

exposed to mean measured concentrations of 0 (control), 14, 24, 38, 58 and 100 mg a.i/L. No 

mortality was observed. Shell growth among oysters exposed to the 24, 38, 58 and 100 mg ai/L 

test concentrations was 2.1, 1.7, 0.80 and 0.41 mm respectively, which was significantly reduced 

compared to control growth (2.9 mm). The 96-hr EC50 for shell growth inhibition is 41 mg a.i/L; 

therefore, acetamiprid is classified as slightly toxic to eastern oysters on an acute exposure basis.

In a 96-hr static acute toxicity study with the degradate IM-1-4, mysid shrimp (A. bahia) were 

exposed to mean measured concentrations of 0 (control), 3.2, 6.7, 14, 27, 55 and 110 mg a.i/L. 

Mortality was 5%, 35%, 65%, 95% and 100% in the 6.7, 14, 27, 55 and 110 mg a.i/L treatment 

levels, respectively. Lethargy was reported in all of the surviving mysids exposed to the 27 and 

55 mg ai/L treatment levels. The LC50 is 19 mg a.i/L and the NOAEC is 3.2 mg a.i/L; IM-1-4 is 

classified as slightly toxic to estuarine/marine invertebrates on an acute exposure basis.
128 

Table B5. Acute toxicity of acetamiprid and degradates to estuarine/marine invertebrates.

Species Test substance LC50 

mg ai/L

Toxicity 

Category MRID Study Classification

Eastern oyster 

shell deposition 

(Crassostrea 

virginica)

Flow-through 

Technical 

acetamiprid 41 Slightly toxic 44988410 Acceptable 

Mysid 

(Americamysis bahia)

Technical 

acetamiprid 0.066* Very highly toxic 44651869 Acceptable 

Mysid 

(Americamysis bahia) 99.6% IM-1-4 19 Slightly toxic 44651870 Acceptable 

* Most sensitive endpoint 

A 21-day chronic toxicity study was conducted with daphnids at concentrations of 0 (control), 2, 

5, 9, 18, 37 and 74 mg ai/L (MRID 44651871). Survival was reduced to 57% at the highest test 

concentration. Significant reduction in length (8%), weight (24%) and mean number of 

offspring (50%) were observed at 9 mg ai/L, the LOAEC. The NOAEC is 5 mg ai/L based on 

reduced growth and reproduction (Table B6). 

A 21-day chronic toxicity study of degradate IM-1-5 was conducted with daphnids at nominal 

concentrations of 0 (control), 6.3, 13, 25, 50 and 100 mg ai/L (MRID 44651871). Significant 

reduction in mean number of offspring (30%) was observed at 50 mg ai/L, the LOAEC. The 

NOAEC is 25 mg ai/L based on impaired reproduction. 

A 28-day flow-through chronic toxicity study was conducted with mysid shrimp exposed at 

mean measured concentrations of 0 (control), 0.93, 1.4, 2.5, 4.7, 10 and 20 μg ai/L. Survival 

rates of 85%, 80%, 92%, 93%, 93% and 63% was observed in the 0.93, 1.4, 2.5, 4.7, 10 and 20 

μg ai/L treatment levels respectively. Only the 20 μg ai/L was statistically significant different 

from the control in terms of reduced survival, and further analyses were not conducted on this 

concentration. Reduction in male dry body weight was the most sensitive endpoint; the NOAEC 

is 2.5 μg ai/L and the LOAEC is 4.7 μg ai/L. 

Table B6. Chronic toxicity of acetamiprid and degradates to aquatic invertebrates.

Species Test 

Substance NOAEC LOAEC Endpoints Affected MRID Study Classification

Waterflea 

(Daphnia 

magna)

Technical 

acetamiprid 

5.0 mg 

ai/L 

9.0 mg 

ai/L 

Reduced 

offspring 

production 

44651871 Acceptable 

Waterflea 

(Daphnia 

magna)

98.9% IM-1-5 

degradate 25 mg ai/L 51 mg 

ai/L 

Number of 

young per 

female 

46255609 Supplemental 

Mysid 

(Americamysis 

bahia)

Technical 

acetamiprid 

0.0025 mg 

ai/L*

0.0047 mg 

ai/L 

Reduced body 

weight in males 44651873 Acceptable 

* Most sensitive endpoint
129 

Aquatic Plants

Tier 1 toxicity testing with aquatic nonvascular plants indicates that acetamiprid had no effect on 

the growth of green algae Pseudokirchneriella subcapitata, cyanobacteria Anabaena flos-aquae,

freshwater diatoms Navicula pelliculosa or marine diatoms Skeletonema costatum at the highest 

concentrations tested (range: 1.0 to 1.3 mg ai/L) (Table B7). Tier 1 toxicity testing with aquatic 

vascular plants indicates that acetamiprid had no effect on the growth of duckweed (Lemna 

gibba) at the highest concentration tested, i.e., 1.0 mg ai/L. 

Table B7. Toxicity of acetamiprid to aquatic plant species.

Species Test 

substance

NOAEC 

(mg ai/L) 

EC50

(mg ai/L) MRID Study Classification

Aquatic Vascular Plants 

Duckweed (Lemna gibba) Technical 

acetamiprid 1.0 >1.0 44988415 Acceptable 

Aquatic Non-vascular Plants 

Green algae 

(Pseudokirchneriella 

subcapitata) 

Technical 

acetamiprid 1.3 >1.3 44988414 Acceptable 

Marine diatom

(Skeletonema costatum)

Technical 

acetamiprid 1.0 >1.0 44988418 Acceptable 

Freshwater diatom

(Navicula pelliculosa)

Technical 

acetamiprid 1.1 >1.1 44988417 Acceptable 

Cyanobacteria 

(Anabaena flos-aquae) 

Technical 

acetamiprid 1.3 >1.3 44988416 Acceptable 

Terrestrial Organisms 

Tables B8 to B15 contains all available terrestrial toxicity endpoints from registrant-submitted 

studies. Below is a brief summary of available terrestrial toxicity studies. 

Birds

The acute oral toxicity of acetamiprid to 4-to-8-month-old zebra finches (Taeniopygia guttata

aka poephila guttata) was assessed over 14 days. Acetamiprid was administered to birds at 

nominal doses of 1.8, 2.5, 3.6, 5, 7, and 10 mg ai/kg bw. The 14-day acute oral LD50 is 5.68 mg 

ai/kg bw (Table B8). At least one clinical sign of toxicity or observation of abnormal behavior 

was recorded in all treatment groups, but not in the control group. Symptoms ranged from 

transient ruffled appearance in the lowest dose group (1.8 mg ai/kg bw) to lethargy, wing droop, 

prostrate posture, loss of coordination, loss of righting reflex, depressed behavior, and minor 

muscle fasciculation in higher dose groups. Acetamiprid is therefore classified as very highly 

toxic to zebra finches on an acute oral exposure basis. 

The acute oral toxicity of acetamiprid to mallard ducks (Anas platyrhynchos) was assessed over 

14 days at measured doses of 0 (control), 43, 64, 85, 124, and 181 mg ai/kg-bw. Mortality was 

0% in the control and 43 mg ai/kg-bw doses, and 40%, 40% 80% and 100% in the 64, 85, 124 
130 

and 181 mg ai/kg-bw doses. Sublethal effects, including abnormal behavior and loss of 

coordination, were reported at all doses. The 14-day LD50 is 84.4 mg ai/kg-bw; the NOAEL is 

<43 mg ai/kg-bw based on impaired behavior. Acetamiprid is classified as moderately toxic to 

mallard ducks on an acute oral exposure basis (Table B8). 

Table B8. Acute oral toxicity of technical grade acetamiprid to birds.

Species Test 

Substance

LD50 

(mg ai/kg-bw)

Toxicity 

Category MRID Study 

Classification

Zebra finch 

(Taeniopygia guttata) 

Technical 

acetamiprid 5.68* Very highly toxic 48407701 Acceptable 

Mallard duck 

(Anas platyrhynchos) 

Technical 

acetamiprid 84.4 Moderately 

toxic 44651859 Acceptable 

* Most sensitive endpoint 

The subacute dietary toxicity of acetamiprid to mallard duck was assessed at concentrations of 0 

(control), 200, 1000 and 5000 mg a.i/kg-diet. Mortality was 10% at the 1000 mg ai/kg-diet 

concentration and 40% at the 5000 mg ai/kg-diet concentration. Sublethal effects including 

imbalance and reduced food consumption were reported at in all surviving birds at the 1000 and 

5000 mg ai/kg-diet concentrations. The subacute dietary LC50 is >5000 mg ai/kg-diet. The 

NOAEC is 200 mg ai/kg-diet based on reduced survival, behavioral effects and reduced food 

consumption. Acetamiprid is classified as slightly toxic to birds on a subacute dietary exposure 

basis (Table B9). 

The subacute dietary toxicity of acetamiprid to 10-day old bobwhite quail (Colinus virginianus) 

was assessed at concentrations of 0 (control), 1000 and 5000 mg ai/kg-diet. Mortality was 20% 

at the 5000 mg ai/kg-diet concentration, the only mortalities in the study. Food consumption was 

markedly depressed in the 5000 mg ai/kg-diet treatment group, the only sublethal effect reported. 

The LC50 is >5000 mg ai/kg-diet and the NOAEC is 1000 mg ai/kg-diet based on reduced 

survival and decreased food consumption. Acetamiprid is classified as practically nontoxic to 

bobwhite quail on a subacute dietary basis. 

The subacute dietary toxicity of the acetamiprid degradate IM-1-4 to mallard duck was assessed 

at test concentrations of0 (control), 5, 50, 500, 2500 and 5000 mg ai/kg-diet. No mortalities or 

sublethal effects were reported. The subacute dietary LC50 is >5000 mg ai/kg-diet. The NOAEC 

is 5000 mg ai/kg-diet. IM-1-4 is classified as practically nontoxic to birds on a subacute dietary 

exposure basis. 
131 

Table B9. Subacute dietary toxicity of acetamiprid to birds.

Species Test 

substance

LC50

(mg ai/kg-diet)

Toxicity 

Category MRID Study Classification

Mallard duck 

(Anas platyrhynchos) 

Technical 

acetamiprid 

>5000 Practically 

non-toxic 44651861 Supplemental 

Bobwhite quail 

(Colinus virginianus) 

Technical 

acetamiprid >5000 Practically 

non-toxic 44651860 Supplemental 

Mallard duck 

(Anas platyrhynchos) 

IM-1-4 

degradate >5000 Practically 

non-toxic 44651862 Acceptable 

Chronic toxicity to birds was uncertain in past risk assessments because of deficiencies in the 

avian reproduction studies with both the mallard (MRID 44988408) and the northern bobwhite 

quail (MRID 44988407). The initial mallard duck reproduction study provided an estimated 

NOAEC of 125 mg ai/kg diet based on reductions in adult female body weight. The previous 

bobwhite quail reproduction study showed significant reductions in hatchling body weights at all 

treatment concentrations and thus failed to establish a NOAEC; the LOAEC was 250 mg ai/kgdiet. Subsequent studies were submitted (Table B10). 

In a one-generation reproductive toxicity study (MRID 46369204), acetamiprid was 

administered to mallard ducks at measured concentrations of 0 (control), 60.2, 134, 258, and 461 

mg ai/kg-diet. Both male and female body weight gains were statistically-reduced compared to 

the controls; the male body weights were affected at all treatment levels (70% at lowest 

treatment), while female body weight gains were reduced at the 258 and 461 mg ai/kg-diet 

treatment levels (roughly 50%). No other effect on any adult parameter was observed. The 

number of eggs laid was statistically-reduced at the 461 mg ai/kg-diet level compared to the 

control (673 versus 896 eggs for 17 laying pairs). In addition, the number of eggs set, the 

number of viable embryos, and hatchling weights were statistically-reduced at the 461 mg ai/kgdiet level. No other effect on any reproductive endpoint was observed. Based on as statistically 

significant 3% decrease in male bodyweight gain in the lowest treatment group, a NOAEC was 

not established for the study, i.e., NOAEC<60.2 mg ai/kg diet; the LOAEC is 60.2 mg ai/kg-diet. 

The NOAEC for reproductive effects is 258 mg ai/kg-diet. 

In a one-generation reproductive toxicity study (MRID 46555601), acetamiprid was 

administered to bobwhite quail at measured concentrations of 0 (control), 89.7, 184, 385 and 775 

mg ai/kg-diet. No treatment-related effects were observed on adult survival or food 

consumption, or upon terminal necropsy of all decedent and surviving birds. There was a 

significant reduction (18%) in adult female body weight change at the highest treatment level. 

There were significant reductions in eggs set, viable embryos, viable embryos to eggs set, live 

embryos, number hatched, number of hatchlings to eggs laid, hatchling survival, hatchling 

survival to eggs set and hatchling survival to number hatched. The NOAEC and LOAEC for the 

study are 89.7 and 184 mg ai/kg-diet, respectively 
132 

Table B10. Reproductive chronic toxicity of technical grade acetamiprid to birds.

Species Test 

Substance

NOAEC 

(mg ai/kg diet)

LOAEC 

(mg ai/kg-diet) MRID Study 

Classification

Mallard duck 

(Anas platyrhynchos) 

Technical 

acetamiprid <60.2* 60.2 46369201 Supplemental 

Northern bobwhite 

quail 

(Colinus virginianus) 

Technical 

acetamiprid 89.7 184 46555601 Acceptable 

* Most sensitive endpoint 

Mammals

The available data indicate that acetamiprid is moderately toxic to mammals on an acute oral 

exposure basis (LD50=146 mg ai/kg-bw). The original Section 3 risk assessment reported an 

LD50=167 mg ai/kg. Acute oral toxicity tests were also conducted on several metabolites and 

degradation products of acetamiprid. Results of these tests show that these compounds are 

considerably less toxic than the parent compound, and are classified as slightly toxic or 

practically nontoxic to mammals (Table B11). 

Table B11. Acute toxicity of acetamiprid and degradates to mammals.

Species Test 

substance

LD50 

(mg ai/kg-bw) 

Toxicity 

Category MRID Classification

Laboratory rat 

Rattus rattus

Technical 

acetamiprid 146 Moderately 

toxic 44651833 Acceptable 

Laboratory rat 

Rattus rattus 

IM-1-4 

(99.6%) 

degradate 

1088 Slightly 

toxic 44651834 Acceptable 

Laboratory rat 

Rattus rattus 

IM-1-2 

(99.9%) 

degradate 

2176 Practically 

nontoxic 44988422 Acceptable 

Laboratory rat 

Rattus rattus 

IM-1-2 

(99.6%) 

degradate 

>5000 Practically 

nontoxic 44651835 Acceptable 

Laboratory rat 

Rattus rattus 

IM-0 

degradate 1792 Practically 

nontoxic 44988421 Acceptable 

Laboratory rat 

Rattus rattus 

IC-0 

degradate >5000 Practically 

nontoxic 44988420 Acceptable 

Consistent results were reported for two chronic studies and a 13-week subchronic study of 

acetamiprid in rats (Table B12). Reduction in growth, as measured by body weight, weight gain, 

and food consumption, were observed at test concentrations of 400-800 mg ai/kg-diet and 

greater, whereas test concentrations of 160-280 mg ai/kg-diet caused no significant effects. In 
133 

addition to growth endpoints, reproductive effects were also observed at 280 mg ai/kg-diet in a 

two-generation study (MRID 44988430). The NOAEC (160 mg/kg diet) that will be used for risk 

assessment will be based on the growth endpoints from the 2-year chronic feeding study (MRID 

44988429). 

Table B12. Chronic toxicity of acetamiprid to mammals.

Species 

(Test Type) 

Test 

Substance Measured Effect NOAEC 

(mg ai/kg diet)

LOAEC 

(mg ai/kg-diet) MRID 

Laboratory Rat 

(Subchronic 

Dietary: 13 

weeks) 

Technical 

acetamiprid 

Body weight, weight 

gain, and food 

consumption 

200 800 44651843 

Laboratory Rat 

(Chronic feeding: 

24 months) 

Technical 

acetamiprid 

Female body weight, 

female weight gain 160 400 44988429; 

45245304 

Laboratory Rat 

(Two-generation 

reproduction) 

Technical 

acetamiprid 

Parental Toxicity: 

Body weight, weight 

gain, food 

consumption 

280 800 

44988430 

Offspring Toxicity: 

Pup weight, litter size, 

viability and weaning 

indices, age to 

maturation 

280 800 

Reproductive Toxicity: 

Litter size, pup 

weights 

280 800 

Terrestrial Invertebrates

Supplemental acute oral and contact honeybee (Apis mellifera) toxicity tests are available (Table 

B13). Honeybees were exposed to acetamiprid in an oral study as follows: 0 (control), 1.38, 2.6, 

4.9, 10.21, 20.0 and 39.17 μg ai/bee. Mortality at 48-hrs averaged 6.7, 26.7, 36.7, 40, 26.7 and 

30.0%, respectively. The study was carried out to 72-hrs, when the mortality averaged 10, 30, 

36.7, 46.7, 50.0 and 30.0%, respectively. Both the 48 and 72-hr mortality in the dimethoate toxic 

reference averaged 50%. Dimethoate is commonly used as a positive control in honeybee 

studies to ensure the population of bees in the study demonstrates expected susceptibility to a 

known toxicant. Since none of the concentrations had greater than 50% mortality, it is not 

possible to calculate an LD50 value for acetamiprid; however, roughly 50% mortality was 

observed in the 20 μg ai/bee treatment. The NOAEC is 1.38 μg ai/bee based on decreased 

survival. With an LD50 of greater than 10.21 μg ai/bee, acetamiprid is classified as practically 

non-toxic to honeybees on an acute exposure basis. 

In the acute contact toxicity test, the percent mortality was 40, 66.7, 46.7, 63.3, and 60% for the 

6.25, 12.5, 25, 50, and 100 μg ai/bee test groups, respectively. The LC50 for the contact study 

was reported as 8.1 μg/bee. However, there is uncertainty in this LC50 value since no clear doseresponse relationship was apparent. Since percent mortality was 66.7% at 12.5 μg ai/bee, the 

median mortality concentration is considered to be below this value (i.e., <12.5) suggesting that 
134 

acetamiprid should be considered moderately toxic to honeybees on an acute contact exposure 

basis. 

In addition to honeybees, the effect of acetamiprid on bumble bees, Bombus terrestris, was 

investigated. Bumble bees were exposed to acetamiprid for 48 hours in both an acute oral and 

acute contact toxicity test. Measured concentrations in the oral toxicity test were 0 (control), 

3.36, 6 76, 10.37, 21.36, and 31.78 μg ai/bee. By 48 hours in the oral test, there was 0.0, 18.2, 

1.0, 37.5, and 100.0% mortality in the 3.36, 6.76, 10.37, 21.36, and 31.78 μg ai/bee 

concentrations and 8.3% in the control. The calculated LD50 is 22.32 μg ai/bee and the NOAEC 

is 10.37 μg ai/bee, despite the mortality noted in the 6.76 μg ai/bee test concentration. The 

contact nominal concentration was 100 μg ai/bee and a negative control. At 48-hrs there was 

3.3% mortality in both groups. The contact LD50 is >100 μg ai/bee and the NOAEC is 100 μg 

ai/bee. Based on these results, acetamiprid is classified as practically nontoxic to bumble bees 

on both an acute oral and contact exposure basis. 

Table B13. Acute toxicity of technical grade acetamiprid to non-target terrestrial 

invertebrates.

Species Test substance LD50

(μg ai/bee) Toxicity Category MRID Study 

Classification

Honey bee 

(Apis mellifera) 

Technical 

acetamiprid 

>10.21 

(oral) Slightly-toxic 44651874 Supplemental 

Technical 

acetamiprid 

<12.5 

(contact) Moderately toxic 44651874 Supplemental 

Bumble bee 

(Bombus 

terrestris) 

Technical 

acetamiprid 

22.32 

(oral) 

Practically 

nontoxic 45932503 Supplemental 

Technical 

acetamiprid 

>100 

(contact) 

Practically 

nontoxic 45932503 Supplemental 

A toxicity of residues on foliage study for honeybees was submitted (MRID 44651875) but was 

deemed unacceptable due to low recovery of acetamiprid on treated foliage. A second residues 

on foliage toxicity study was submitted, but has not yet been reviewed by EFED (MRID 

45346901). Two semi-field studies conducted to evaluate the possible effect of acetamiprid on 

honeybee behavior were also submitted (MRIDs 45932504; 45932505), and were classified as 

supplemental26. Both studies used tents to expose honeybees via contact with forage and/or 

overspray, and applications rates were equivalent to 0.15 and 0.09 lbs ai/A, which is in line with 

single application rates for many registered and proposed crop uses. Mortality, flight frequency, 

and foraging behavior were evaluated relative to a control and a known toxic standard. No 

significant effects on any endpoints were observed in either study from acetamiprid treatments. 

In the ECOTOX database, Iwasa et al., 2004, report an LD50 of 7.07 μg ai/bee in a 24 hr contact 

study. This endpoint was based on nominal concentrations, but indicates that acetamiprid is 

moderately toxic to honeybees. A seven day study with speckled cutworm moth larvae 

(Lacanobia subjuncta) in a leaf litter substrate, Doerr et al., 2004, reported an LC50 of 71.3 

mg/L. These values are provided for qualitative risk characterization. DERs have not yet been 

generated, but the papers have been submitted for evaluation, and will be reviewed as needed for 

 

26 Note: non-guideline studies cannot be rated “acceptable” since there are no guideline standards 
135 

the upcoming registration review risk assessment. 

Several open literature studies of acetamiprid effects on honeybees are available for acetamiprid. 

These studies will be thoroughly reviewed as part of the upcoming registration review risk 

assessment, but are briefly summarized here. El Hassani et al. (2008) exposed bees to 0.1, 0.5, 

and 1 μg of active ingredient, and recorded increases in sucrose responsiveness, locomotor 

activity (total length walked), and responsiveness to water (proboscis extension reflex after 

stimulation by water), which are all considered activating effects since they signify increases in 

specific functions. Conversely, the lowest dose of acetamiprid (i.e., 0.1 μg/bee) also impaired 

olfactory-related learning performance. A follow-up study by Aliouane et al. (2009) supported 

the previous water responsiveness finding. Laurino et al. (2011) found increased mortality in 

bees that ingested 50 and 100 ppm (ng/μl) of a formulation containing acetamiprid (5% ai). 

Mortality attributed to acetamiprid in the higher dose group was 50.85% compared to the control 

group, but these effects were only seen in bees that were starved for two hours before dosing. In 

the same study, bees fed sugar did not show any significant mortality from oral or indirect 

contact exposure to acetamiprid over a 72-hour observation period. In the above studies, 

acetamiprid generally exhibited lower toxicity to bees than a small sample of other 

neonicotinoids insecticides (e.g., clothianidin). This supports a previous open literature 

laboratory study suggesting that nitroguanidine substituted neonicotinoids (e.g., clothianidin, 

imidacloprid, thiamethoxam and dinotefuran) are more toxic to bees than their cyano-substituted 

neonicotinoids (e.g., acetamiprid, thiacloprid) (Iwasa et al., 2004). However, El Hassani et al.

(2008) did show that acetamiprid, but not thiamethoxam, had a detectable impact on bee 

behavior at sublethal doses. 

Effects of the acetamiprid degradate IM-1-5 on adult collembola, Folsomia candida, were 

examined at concentrations of 0 (control), 0.1, 0.5. 2.5, 12.5 and 62.5 mg/kg artificial soil over a 

28- day exposure period (MRID 46255612). Reproduction was the measured endpoint. 

Reproduction was reduced by 15, 14, 8, 6 and 24% in the 0.1, 0.5, 2.5, 12.5 and 62.5 mg/kg 

treatments, respectively; reductions at the 2.5 and 12.5 mg/kg treatment levels were not 

statistically significant. The EC50 for the study is >62.2 mg/kg-soil and the NOAEC is <0.1 

mg/kg-soil. 

Rove beetles, Aleochara bilineata, were exposed to the degradate IM-1-5 at concentrations of 0 

(control), 0.1, 2.5 and 62.5 mg/kg sand substrate over an 87-day period (MRID 46255611). Fly 

pupae (Delia antique) were introduced on days 7, 14 and 21(as food) to evaluate beetle 

reproduction. Adult beetles were removed on day 28, and fly pupae were removed on day 35. 

Beetle emergence was observed from day 39 to 87. Number of emerged beetles was the 

measurement endpoint. There was a 19% reduction in emergence at the highest test 

concentration. The EC50 for the study is >62.5 mg/kg substrate and the NOAEC is 2.5 mg/kg 

substrate. 

In a 14-day acute toxicity study, earthworms (Eisenia foetida) were exposed to acetamiprid at 0 

(control), 4, 8, 15, 30 or 60 mg ai/kg dry weight of artificial substrate (MRID 44988412). The 

reference chemical used was chloroacetamide at 37 mg ai/kg of the substrate. The 14-day LC50

was 9.12 mg ai/kg-substrate. The 7-day LC50 was 10 mg ai/kg substrate. The NOEC and LOEC 

values were not determined. Acetamiprid is considered to be toxic to earthworms up to/and 

above a concentration of 4 mg ai/kg substrate. 
136 

Earthworms (Eisenia foetida) were exposed to IM-1-5 at nominal test concentrations of 0 

(control), 4, 8, 15, 30, and 1000 mg/kg (MRID46255613). By 14 days, there were no mortalities. 

Reductions in body weight by day 14 were 2.9% in the 1000 mg/kg treatment group. No body 

weight reductions were observed in the control or the 4, 8, 15, and 30 mg/kg treatment groups. 

The LC50 was >1000 ppm; a NOEC value was estimated at 1000 mg/kg. 

Earthworms (Eisenia foetida) were exposed to the IM-1-5 degradate over an 8-week period at 

nominal test concentrations of 0 (control), 0.1, 0.5, 2.5, 12.5, and 62.5 mg/kg in artificial soil 

(MRID 46255614). By 28 days, there were no mortalities in the control or treatment groups. 

There were no significant differences in adult body weight changes or number of juveniles 

produced in any treatment group compared to the control. The LC50 was >62.5 mg/kg and the 

NOEC value was 62.5 mg/kg. 

Terrestrial Plants

The effect of acetamiprid on the seedling emergence and vegetative vigor of monocot: corn (Zea 

mays), oat (Avena sativa), onion (Allium cepa), perennial ryegrass (Lolium perenne), and dicot: 

cabbage (Brassica oleracea), cucumber (Cucumis sativus), lettuce (Lactuca sativa), soybean 

(Glycine max), tomato (Lycopersicon esculentum), and turnip (Brassica rapa) crops was studied 

at nominal concentrations (MRID 44988413). For the seedling emergence study, nominal 

concentrations were as follows: cabbage, cucumber, onion and tomato: 0.041, 0.081, 0.16, 0.33 

and 0.65 lbs ai/A; corn, lettuce, oat, perennial ryegrass, soybean and turnip: 0.65 lbs ai/A. For the 

vegetative vigor study, nominal concentration were as follows: cabbage, oat, onion, soybean and 

tomato: 0.65 lbs ai/A; corn and cucumber: 0.041, 0081, 0.16, 0.33 and 0.65 lbs ai/A; lettuce: 

0.005, 0.01, 0.02, 0.041, 0.081 and 0.16 lbs ai/A; perennial ryegrass: 0.041, 0.081, 0.16, 0.33 and 

0.65 lbs ai/A; and turnip: 0.02, 0.041, 0.081, 0.16, 0.33 and 0.65 lbs ai/A. 

The seedling emergence part of this study was classified as supplemental because the weight of 

the seedlings was not measured. Measurement of both plant weight and plant height are 

required, but only plant height was measured in this study. The percent seedling emergence was 

not affected in all species tested after exposure to acetamiprid. There was, however, reduction in 

shoot length of cucumber, onion, and tomato exposed to acetamiprid at 0.15, 0.32 and 0.62 lbs 

ai/A. The most sensitive monocot species was onion with an EC25 of 0.23 lbs ai/A. The most 

sensitive dicot species was cucumber, with an EC25 of 0.16 lbs ai/A (Table B14). The NOEC 

based on the seedling emergence (shoot length) in cucumber (dicot) and onion (monocot) was 

0.077 lbs ai/A. 

The vegetative vigor part of this study was acceptable for all species except lettuce. The test 

with lettuce was classified as supplemental because significant adverse phytotoxic effects were 

observed in the control plants. In the vegetative vigor test, the shoot length in all species was not 

affected by acetamiprid treatment. Plant weight was also not affected in cabbage, corn, 

cucumber, oat, onion, soybean and tomato exposed to the compound. There was, however, a 

reduction in the plant weight of lettuce, perennial ryegrass, and turnip exposed to various 

concentrations of acetamiprid. The most sensitive monocot species in the vegetative vigor test 

was perennial ryegrass, with an EC25 of 0.46 lbs ai/A and a NOAEC of 0.31 lbs ai/A. The most 

sensitive dicot species was lettuce, with a EC25 of 0.016 lbs ai/A and a NOEC of 0.0094 lbs ai/A. 
137 

A subsequent study was submitted concerning the effect of acetamiprid on vegetative vigor on 

lettuce alone (MRID 45921401). In this study, the EC25 and NOAEC for plant weight were 

0.012 and <0.0025 lbs ai/A, respectively. Shoot length was the more sensitive parameter with an 

EC25 of 0.0056 and a NOAEC of 0.0025 lbs ai/A. Two other studies more closely examined the 

phytotoxic effects of acetamiprid on lettuce. Both studies (MRID 46229601 and 46229602) 

reported that the variety of lettuce used in the first two studies, buttercrunch, accounted for the 

greater sensitivity of lettuce relative to other species tested, and other varieties of lettuce 

exhibited reduced sensitivities. 

Table B14. Summary of endpoints (lbs ai/A) in terrestrial plant toxicity studies submitted 

for acetamiprid. 

Species Seedling emergence Vegetative vigor 

NOAEC EC25 NOAEC EC25

Monocots 

Oat 0.62 >0.62 0.67 >0.67 

Corn 0.62 >0.62 0.59 >0.59 

Onion 0.077* 0.23* 0.65 >0.65 

Ryegrass 0.62 >0.62 0.31* 0.46* 

Dicots 

Cucumber 0.077* 0.16* 0.59 >0.59 

Soybean 0.62 >0.62 0.65 >0.65 

Turnip 0.62 >0.62 0.031† 0.2 

Lettuce 0.62 >0.62 0.0025* 0.0056* 

Tomato 0.077 0.16 0.65 >0.65 

Cabbage 0.62 >0.62 0.67 >0.67 

* Most sensitive endpoint 

†

 EC05 is used when calculated EC25 is less than derived NOAEC. 

 
138 

Appendix C. Example ECOSAR Output 

Output for IM-1-5

SMILES : c1cc(ncc1CN(C)C(C)=N)CL 

CHEM : 

CAS Num: 

ChemID1: 

ChemID2: 

ChemID3: 

MOL FOR: C9 H12 CL1 N3 

MOL WT : 197.67 

Log Kow: -0.68 (KowWin estimate) 

Melt Pt: 

Wat Sol: 1.7E+005 mg/L (WskowWin estimate) 

ECOSAR v1.00 Class(es) Found 

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

Halopyrdines 

 Predicted 

ECOSAR Class Organism Duration End Pt mg/L (ppm) 

=========================== ================== ======== ====== 

========== 

Halopyrdines : Fish 96-hr LC50 0.184 

Halopyrdines : Daphnid 48-hr LC50 1.369 

Halopyrdines : Fish 32-day ChV 27.067 

Halopyrdines : Daphnid ChV 0.752 ! 

=========================== ================== ======== ====== 

========== 

Neutral Organic SAR : Fish 96-hr LC50 28010.680 

(Baseline Toxicity) : Daphnid 48-hr LC50 11695.474 

 : Green Algae 96-hr EC50 1681.517 

 : Fish ChV 2821.084 

 : Daphnid ChV 672.943 

 : Green Algae ChV 373.311 

 Note: * = asterisk designates: Chemical may not be soluble 

 enough to measure this predicted effect. 

 

 Note: ! = exclamation designates: The toxicity value was determined from 

 a predicted SAR using established acute-to-chronic ratios and ECOSAR 

 regression techniques which are documented in the supporting Technical 

 Reference Manual. When possible, this toxicity value should be 

 considered in a weight of evidence approach. 

 

Halopyrdines : 
139 

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

 For Fish and Daphnid Acute Toxicity Values: If the log Kow of the chemical 

is greater than 5.0, or if the compound is solid and the LC50 exceeds the 

water solubility by 10X, no effects at saturation are predicted for these 

endpoints. 

 

 For Green Algae Acute Toxicity Values: If the log Kow of the chemical is 

greater than 6.4, or if the compound is solid and the EC50 exceeds the water 

solubility by 10X, no effects at saturation are predicted for these endpoints. 

 

 For All Chronic Toxicity Values: If the log Kow of the chemical is greater 

than 8.0, or if the compound is solid and the ChV exceeds the water solubility 

by 10X, no effects at saturation are predicted for these endpoints. 

 

ECOSAR v1.00 SAR Limitations: 

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

Maximum LogKow: 5.0 (LC50) 

Maximum LogKow: 6.4 (EC50) 

Maximum LogKow: 8.0 (ChV) 

Maximum Mol Wt: 1000 

 

Baseline Toxicity SAR Limitations: 

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

Maximum LogKow: 5.0 (Fish 96-hr LC50; Daphnid LC50) 

Maximum LogKow: 6.4 (Green Algae EC50) 

Maximum LogKow: 8.0 (ChV) 

Maximum Mol Wt: 1000 

 

 
140 

Appendix D. Reference List for OPPTS 835 Guidelines 

The Office of Prevention, Pesticides, and Toxic Substances (OPPTS) became the Office of 

Chemical Safety and Pollution Prevention (OCSPP) in 2011. The guidelines have not been 

updated since the name change and the titles still use OPPTS. 

OPPTS Guideline Citation

Hydrolysis 

835.2120 

(161-1) 

USEPA. 2008. Fate, Transport, and Transformation Guidelines. OPPTS 835.2120 Hydrolysis. E. 

712-C-08-012. October 2008. Office of Prevention, Pesticides, and Toxic Substances. United States 

Environmental Protection Agency. Available at 

http://www.epa.gov/ocspp/pubs/frs/publications/Test_Guidelines/series835.htm (Accessed May 5, 

2012). 

Aqueous Photolysis 

835.2240 

(161-2) 

USEPA. 2008. Fate, Transport, and Transformation Guidelines. OPPTS 835.2240 

Photodegradation in Water. E. 712-C-08-013. October 2008. Office of Prevention, Pesticides, and 

Toxic Substances. United States Environmental Protection Agency. Available at 

http://www.epa.gov/ocspp/pubs/frs/publications/Test_Guidelines/series835.htm (Accessed May 5, 

2012). 

Soil Photolysis 

835.2410 

(161-3) 

USEPA. 2008. Fate, Transport, and Transformation Guidelines. OPPTS 835.2410 

Photodegradation in Soil. E. 712-C-08-015. October 2008. Office of Prevention, Pesticides, and 

Toxic Substances. United States Environmental Protection Agency. Available at 

http://www.epa.gov/ocspp/pubs/frs/publications/Test_Guidelines/series835.htm (Accessed May 5, 

2012). 

Aerobic Soil 

Metabolism 

835.4100 

(162-1) 

USEPA. 2008. Fate, Transport, and Transformation Guidelines. OPPTS 835.4100 Aerobic Soil 

Metabolism; OPPTS 835.4200 Anaerobic Soil Metabolism. EPA712-C-08-016 & E. 712-C-08-017. 

October 2008. Office of Prevention, Pesticides, and Toxic Substances. United States Environmental 

Protection Agency. Available at 

http://www.epa.gov/ocspp/pubs/frs/publications/Test_Guidelines/series835.htm (Accessed May 17, 

2012). 

Anaerobic Soil 

Metabolism 

835.4200 

(162-2) 

Aerobic Aquatic 

Metabolism 

835.4300 

(162-4) 

USEPA. 2008. Fate, Transport, and Transformation Guidelines. OPPTS 835.4300 Aerobic Aquatic 

Metabolism; OPPTS 835.4400 Anaerobic Aquatic Metabolism. EPA 712-C-08-018 & E. 712-C-08-

019. October 2008. Office of Prevention, Pesticides, and Toxic Substances. United States 

Environmental Protection Agency. Available at 

http://www.epa.gov/ocspp/pubs/frs/publications/Test_Guidelines/series835.htm (Accessed May 17, 

2012). Anaerobic Aquatic 

Metabolism 

835.4400 

(162-3) 

Sorption coefficients 

835.1230 

(163-1) 

USEPA. 2008. Fate, Transport, and Transformation Guidelines. OPPTS 835.1230 

Adsorption/Desorption (Batch Equilibrium). E. 712-C-08-009. October 2008. Office or Prevention, 

Pesticides, and Toxic Substances. United States Environmental Protection Agency. Available at 

http://www.epa.gov/ocspp/pubs/frs/publications/Test_Guidelines/series835.htm (Accessed May 5, 

2012). 

Leaching and Aged 

Column Leaching 

835.1240 

USEPA. 2008. Fate, Transport, and Transformation Guidelines. OPPTS 835.1240 Leaching Studies. 

E. 712-C-08-010. October 2008. Office of Prevention, Pesticides, and Toxic Substances. United 

States Environmental Protection Agency. Available at 

http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPPT-2009-0152-0007 (Accessed May 

5, 2012). 
141 

OPPTS Guideline Citation

Terrestrial Field 

Dissipation 

835.6100 

USEPA. 2008. Fate, Transport, and Transformation Guidelines. OPPTS 835.1230 

Adsorption/Desorption (Batch Equilibrium). E. 712-C-08-009. October 2008. Office or Prevention, 

Pesticides, and Toxic Substances. United States Environmental Protection Agency. Available at 

http://www.epa.gov/ocspp/pubs/frs/publications/Test_Guidelines/series835.htm (Accessed May 5, 

2012). 

Aquatic Field 

Dissipation 

835.6200 

USEPA. 2008. Fate, Transport, and Transformation Test Guidelines. OPPTS Aquatic (Sediment) 

Field Dissipation. EPA 712-C-08-021. October 2008. Office of Prevention, Pesticides, and Toxic 

Substances. United States Environmental Available at 

http://www.epa.gov/ocspp/pubs/frs/publications/Test_Guidelines/series835.htm (Accessed May 15, 

2012). 

Bioconcentration 

Factor 

850.1730 

USEPA. 1996. Ecological Effects Test Guidelines. OPPTS 850.1730 Fish BCF. E. 712-C-96-129. 

April 1996. Environmental Fate and Effects Division. Office of Pesticide Programs. United States 

Environmental Protection Agency. Available at 

http://www.epa.gov/opptsmnt/pubs/frs/publications/OPPTS_Harmonized/850_Ecological_Effects_T

est_Guidelines/Drafts/850-1730.pdf (Accessed May 14, 2012). 

Environmental 

Chemistry Method 

USEPA. 1996. Ecological Effects Test Guidelines. OPPTS 850.7100. E. 712-C-96-348. April 1996. 

Office of Prevention, Pesticides, and Toxic Substances. Available at 

http://www.epa.gov/opptsmnt/pubs/frs/publications/OPPTS_Harmonized/850_Ecological_Effects_T

est_Guidelines/Drafts/850-7100.pdf (Accessed May 17, 2012). 

 
142 

Appendix E. Results from Screening Imbibition Program (SIP) and the Screening Tool for 

Inhalation Risk Assessment (STIR) 

The Screening Imbibition Program (SIP v.1.0, Released June 15, 2010) was used to calculate an 

upper bound estimate of exposure using acetamiprid’s solubility (4250 mg/L, MRID 44651803), 

the most sensitive acute and chronic avian toxicity endpoints (Zebra finch with LD50 of 5.68 mg 

ai/kg-bw and Mallard duck NOAEC of less than 60.2 mg/kg-diet) and the most sensitive acute 

and chronic mammalian toxicity endpoints (Rat LD50 of 146 mg ai/kg-bw and NOAEC of 7.1 mg 

ai/kg-bw/day or 160 mg ai/kg-diet). Based on the output, exposure through drinking water alone 

is potential acute and chronic risk to small birds and a potential chronic risk to small mammals. 

Results from SIP are shown below. 

Inhalation is another potential exposure route for terrestrial vertebrates. Based on the vapor 

pressure of acetamiprid (7.5 × 10-10 Torr at 25o

C), acetamiprid is nonvolatile from dry 

nonadsorbing surfaces and non-volatile from water and moist surfaces, and therefore risk from 

inhalation is not expected (AERU, 2012). The 4-hr LC50 inhalation study using rats was greater 

than 1.15 mg/L (MRID 44651837). The STIR model (Screening Tool for Inhalation Risk) was 

used to evaluate inhalation risk to birds and mammals. The endpoints discussed above were used 

in the model. Results from STIR are shown below. 
143 

Results from SIP version 1.0
144 

Results from STIR Version 1.0.xlsx 
145 

Appendix F. Agency risk quotient (RQ) metrics and levels of concern (LOC) for Federallylisted (listed) threatened/endangered and non-listed species 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/NOEC (fish) 

1 21-day EEC/NOEC 

(invertebrates) 

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 

EEC 2

/LC50 (Dietary) 

0.1 

EEC/LD50 (Dose) 

Chronic Potential for effects to non-listed and listed 

animals from chronic exposures EEC 2

/NOAEC 1 

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/ NOEC 

1 

EEC/ EC05
146 

Appendix G. Data Call-In Justification Tables for Non-Guideline Ecological Effects 

Studies 

Study Title: Pollinator Larval Toxicity Study 

Guideline Number: Non-guideline 

Test Substance: Acetamiprid 

Rationale for Requiring the Data 

Acetamiprid is a systemic insecticide and is moderately toxic to young adult honey bees on an 

acute contact exposure basis. Previously submitted studies of acetamiprid do not provide 

information on the potential toxicity to developing honeybee brood (larvae and pupae). Since 

acetamiprid is a systemic pesticide, there is the potential for pollen and nectar to be contaminated 

with the product and subsequently brought back to the hive where larvae may be exposed. 

Therefore, a non-guideline honeybee larval toxicity study is recommended. The registrant should 

submit a proposed protocol for review and approval by EFED prior to initiation of the study.

Practical Utility of the Data 

How will the data be used? 

Data will be used to assess risk to non-target listed and non-listed terrestrial invertebrate species. 

This study would allow the Agency to refine the screening-level hazard assessment for beneficial 

terrestrial invertebrates. The effects data will be used to determine the potential for adverse effects 

on beneficial terrestrial invertebrates through direct effects on larval bees. 

How could the data impact the Agency’s future decision-making? 

EPA is required by section 7(a)(2) of the Endangered Species Act (ESA) to ensure that any action 

it authorizes or takes “...is not likely to jeopardize the continued existence of any endangered or 

threatened species or result in the destruction or adverse modification of critical habitat” and “to 

use the best scientific data available” in carrying out this obligation. The data EPA intends to call 

in are necessary to inform the determination required by ESA as to whether continued registration 

of a pesticide is or is not likely to jeopardize the species or its critical habitat. The lack of these 

data will limit the flexibility that the Agency and registrants have in coming into compliance with 

ESA and could result in use restrictions that are unnecessarily severe. In addition, the lack of these 

data may result in an uncertain assumed risk and potential mitigation of acetamiprid formulations 

under FIFRA. 

Study Title: Residues in Pollen and Nectar/Field Residue Analysis Study 

Guideline Number: Non-guideline 

Test Substance: Acetamiprid 

Rationale for Requiring the Data 

Acetamiprid is a systemic insecticide and is moderately toxic to young adult honey bees on an 

acute contact exposure basis. The systemic nature of the compound necessitates the quantification 

of pollinator-relevant residues in treated flowering plants, since pollinators will be exposed to 

residues from either current or prior season applications (due to the potential for residues to 

accumulate in plants and trees). Residues in edible/transportable-to-hive parts of treated trees and 

plants, particularly pollen-shedding and nectar producing parts (i.e., flowers and, if present, extrafloral nectaries) of plants may inform the potential for risk. 
147 

The Agency will consider multiple crops based on certain selective criteria, including, but not 

limited to, the estimated usage, the application method, and whether the crop is attractive to 

pollinators. Furthermore, the Agency will consider a semi-field, full-field, or greenhouse-based 

protocol lasting at least two years with multiple sampling time-steps. The protocol will depend on 

application type and crop. The registrant should consult the Agency on the design of the protocol 

prior to the initiation of the study. 

Practical Utility of the Data 

How will the data be used? 

To assess risk to non-target listed and non-listed terrestrial invertebrate species. These data would 

allow the Agency to refine the screening level risk assessment for beneficial terrestrial 

invertebrates. Exposure data is an integral part of determining the potential for risk to beneficial 

terrestrial invertebrates through direct exposure from their food sources. 

How could the data impact the Agency’s future decision-making? 

EPA is required by section 7(a)(2) of the Endangered Species Act (ESA) to ensure that any action 

it authorizes or takes “...is not likely to jeopardize the continued existence of any endangered or 

threatened species or result in the destruction or adverse modification of critical habitat” and “to 

use the best scientific data available” in carrying out this obligation. The data EPA intends to call 

in are necessary to inform the determination required by ESA as to whether continued registration 

of a pesticide is or is not likely to jeopardize the species or its critical habitat. The lack of these 

data will limit the flexibility that the Agency and registrants have in coming into compliance with 

ESA and could result in use restrictions that are unnecessarily severe. In addition, the lack of these 

data may result in an uncertain assumed risk and potential mitigation of acetamiprid formulations 

under FIFRA. 

 
148 

Appendix H. Preliminary Estimate of Surface Water Concentrations for Ecological Risk 

Assessment 

An EEC was estimated using the highest single application rate of 23.4 lbs a.i./A. An EEC for 

both a residential use setting and for perimeter treatment are both estimated using different 

assumptions. The perimeter treatment scenario resulted in higher EECs. The estimated 

application area for a perimeter treatment is up to 10 feet from the building and up to 3 foot on 

the surface of the building. A treated area factor was estimated using a housing density of four 

2000 ft2

 houses per acre. Each house has a perimeter of 180 ft and treated area of 2340 ft2 (180 

ft x 13 ft). The estimated treated area per acre is then 9360 ft2

 which results in an estimated 21% 

of an acre (9360ft2/43560ft2/acre). The EEC from the residential scenario was multiplied by 0.21 

to estimate an EEC to use as a screen for the perimeter treatment scenario. For other residential 

uses, it was assumed that half of a lot could be treated. Finally, the rice model was used to 

evaluate potential exposure for a cranberry use. Below are the output files from PRZM/EXAMs, 

GENEEC, and the rice model with EECs shown in Table H1. 

Table H1. Preliminary Screening EECs for Acetamiprid Use in Residential Areas, 

Perimeter Treatments, and for Use on Cranberries 

Scenario Model Area Treated 

Factor 

Estimated Environmental Concentration (mg/L)_ 

Peak 21-day 60-day 

Residential GENEEC 0.5 0.5 0.5 0.5 

Perimeter GENEEC 0.21 0.21 0.21 0.21 

Residential PRZM/EXAMS ** 0.72 0.71 0.70 

Perimeter PRZM/EXAMS 0.21 0.17 0.17 0.17 

Cranberry Rice Model 1.0 0.10 0.10 0.10 

**PRZM/EXAMs was used to estimate exposure in a residential setting in California. The scenario was created 

specifically for California and it may not be conservative for the entire United States. The assumptions made were 

that there was half of the area was pervious and half impervious. It was assumed that half of the pervious surface 

was treated and 10% of the impervious surface was treated. Time series files from runs with an impervious surface 

scenario and residential scenario were combined to arrive at the final EEC. 

 RUN No. 1 FOR acetamiprid ON resident * INPUT VALUES *

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

 RATE (#/AC) No.APPS & SOIL SOLUBIL APPL TYPE NO-SPRAY INCORP

 ONE(MULT) INTERVAL Koc (PPM ) (%DRIFT) (FT) (IN)

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

 23.400( 23.400) 1 1 227.0 4250.0 GRHIFI( 6.6) .0 .0

 FIELD AND STANDARD POND HALFLIFE VALUES (DAYS)

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

 METABOLIC DAYS UNTIL HYDROLYSIS PHOTOLYSIS METABOLIC COMBINED

 (FIELD) RAIN/RUNOFF (POND) (POND-EFF) (POND) (POND)

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

 383.00 2 N/A 34.00- 4216.00 ****** 1344.49

 GENERIC EECs (IN MILLIGRAMS/LITER (PPM)) Version 2.0 Aug 1, 2001

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

 PEAK MAX 4 DAY MAX 21 DAY MAX 60 DAY MAX 90 DAY

 GEEC AVG GEEC AVG GEEC AVG GEEC AVG GEEC

 --------------------------------------------------------------------
149 

 1.01 1.01 1.00 .98 .96

stored as acetres.out 

Chemical: acetamiprid 

PRZM environment: CAresidentialRLF.txt modified Tueday, 20 February 2007 

at 13:04:34 

EXAMS environment: pond298.exv modified Wedday, 15 November 2006 at 

13:47:26 

Metfile: w23234.dvf modified Wedday, 3 July 2002 at 10:04:22 

Water segment concentrations (ppb) 

Year Peak 96 hr 21 Day 60 Day 90 Day Yearly 

1961 39.37 39.29 39.24 39.07 38.9 32.79 

1962 124 123 122 120 119 106 

1963 211 211 209 207 206 192 

1964 273 272 269 266 265 256 

1965 270 270 270 270 269 265 

1966 280 279 279 279 279 274 

1967 508 506 498 488 483 449 

1968 494 494 491 489 489 476 

1969 537 536 535 531 528 509 

1970 562 561 559 554 553 535 

1971 529 529 528 528 528 518 

1972 507 507 507 507 506 499 

1973 582 581 579 577 575 554 

1974 561 561 560 559 558 548 

1975 569 569 568 565 563 548 

1976 554 553 552 552 551 540 

1977 567 567 565 563 563 555 

1978 619 618 616 612 611 592 

1979 678 677 675 671 668 644 

1980 682 682 680 678 675 655 

1981 693 692 689 685 683 662 

1982 923 920 909 900 896 864 

1983 894 893 890 889 887 856 

1984 821 821 819 818 817 802 

1985 796 795 794 793 793 776 

1986 825 824 822 817 815 786 

1987 802 801 799 795 794 774 

1988 759 758 757 755 755 741 

1989 713 713 712 709 709 698 

1990 692 692 690 689 688 674 

Sorted results 

Prob. Peak 96 hr 21 Day 60 Day 90 Day Yearly 

0.032258064516129 923 920 909 900 896 864 

0.0645161290322581 894 893 890 889 887 856 

0.0967741935483871 825 824 822 818 817 802 

0.129032258064516 821 821 819 817 815 786 

0.161290322580645 802 801 799 795 794 776 

0.193548387096774 796 795 794 793 793 774 

0.225806451612903 759 758 757 755 755 741 

0.258064516129032 713 713 712 709 709 698 

0.290322580645161 693 692 690 689 688 674 

0.32258064516129 692 692 689 685 683 662 
150 

0.354838709677419 682 682 680 678 675 655 

0.387096774193548 678 677 675 671 668 644 

0.419354838709677 619 618 616 612 611 592 

0.451612903225806 582 581 579 577 575 555 

0.483870967741936 569 569 568 565 563 554 

0.516129032258065 567 567 565 563 563 548 

0.548387096774194 562 561 560 559 558 548 

0.580645161290323 561 561 559 554 553 540 

0.612903225806452 554 553 552 552 551 535 

0.645161290322581 537 536 535 531 528 518 

0.67741935483871 529 529 528 528 528 509 

0.709677419354839 508 507 507 507 506 499 

0.741935483870968 507 506 498 489 489 476 

0.774193548387097 494 494 491 488 483 449 

0.806451612903226 280 279 279 279 279 274 

0.838709677419355 273 272 270 270 269 265 

0.870967741935484 270 270 269 266 265 256 

0.903225806451613 211 211 209 207 206 192 

0.935483870967742 124 123 122 120 119 106 

0.967741935483871 39.37 39.29 39.24 39.07 38.9 32.79 

0.1 824.6 823.7 821.7 817.9 816.8 800.4 

 Average of yearly averages: 546.026333333333 

Inputs generated by pe5.pl - November 2006 

Data used for this run: 

Output File: acetres 

Metfile: w23234.dvf 

PRZM scenario: CAresidentialRLF.txt 

EXAMS environment file: pond298.exv 

Chemical Name: acetamiprid 

Description Variable Name Value Units Comments 

Molecular weight mwt 222.68 g/mol 

Henry's Law Const. henry 5.2E-14 atm-m^3/mol 

Vapor Pressure vapr 7.5E-10 torr 

Solubility sol 4250 mg/L 

Kd Kd mg/L 

Koc Koc 227 mg/L 

Photolysis half-life kdp 34 days Half-life 

Aerobic Aquatic Metabolism kbacw 1974 days Halfife 

Anaerobic Aquatic Metabolism kbacs 4116 days Halfife 

Aerobic Soil Metabolism asm 383 days Halfife 

Hydrolysis: pH 7 0 days Half-life 

Method: CAM 1 integer See PRZM manual 

Incorporation Depth: DEPI 0 cm 

Application Rate: TAPP 26.22 kg/ha 

Application Efficiency: APPEFF 0.99 fraction 

Spray Drift DRFT 0 fraction of application rate applied to pond 

Application Date Date 01-01 dd/mm or dd/mmm or dd-mm or dd-mmm 

Record 17: FILTRA 

 IPSCND 1 

 UPTKF 

Record 18: PLVKRT 

 PLDKRT 

 FEXTRC 0.5 

Flag for Index Res. Run IR EPA Pond 
151 

Flag for runoff calc. RUNOFF none none, monthly or total(average of 

entire run) 

stored as acetimp1.out 

Chemical: acetamiprid 

PRZM environment: CAImperviousRLF.txt modified Tueday, 20 February 2007 

at 13:05:44 

EXAMS environment: pond298.exe modified Wedday, 15 November 2006 at 13:47:26 

Metfile: w23234.dvf modified Wedday, 3 July 2002 at 10:04:22 

Water segment concentrations (ppb) 

Year Peak 96 hr 21 Day 60 Day 90 Day Yearly 

1961 13.94 13.84 13.43 12.65 12.22 10.08 

1962 20.15 20.06 19.77 19.2 18.87 17.26 

1963 36.5 36.33 35.63 34.45 33.78 30.14 

1964 31.34 31.32 31.21 30.98 30.82 29.72 

1965 51.3 51.14 50.46 49.09 48.31 44.99 

1966 59.57 59.4 58.76 58.33 57.81 54.67 

1967 96.46 96.12 94.63 91.86 90.34 82.55 

1968 98.5 98.32 97.67 96.4 95.57 90.78 

1969 94.55 94.49 94.13 93.5 93.01 89.44 

1970 91.67 91.61 91.34 90.67 90.19 86.78 

1971 86.87 86.81 86.55 86.01 85.65 82.77 

1972 82.58 82.52 82.32 81.82 81.45 78.75 

1973 105 105 104 102 101 95.05 

1974 118 118 117 115 114 108 

1975 109 109 108 108 107 104 

1976 106 106 106 106 105 102 

1977 113 113 112 111 110 105 

1978 107 107 107 106 105 101 

1979 104 104 103 103 102 98.21 

1980 101 101 100 99.61 99.11 95.47 

1981 92.38 92.34 92.16 91.87 91.64 88.68 

1982 97.7 97.56 97 95.99 95.37 91.44 

1983 102 102 102 101 99.84 95.19 

1984 96.4 96.34 96.01 95.4 94.93 91.36 

1985 97.17 97.04 96.57 96.12 95.64 91.79 

1986 101 101 101 99.62 98.91 94.6 

1987 104 104 103 102 102 97.12 

1988 99.71 99.61 99.22 98.44 97.91 94.06 

1989 100 99.96 99.52 98.7 98.13 94.09 

1990 107 106 106 105 104 99.42 

Sorted results 

Prob. Peak 96 hr 21 Day 60 Day 90 Day Yearly 

0.032258064516129 118 118 117 115 114 108 

0.0645161290322581 113 113 112 111 110 105 

0.0967741935483871 109 109 108 108 107 104 

0.129032258064516 107 107 107 106 105 102 

0.161290322580645 107 106 106 106 105 101 

0.193548387096774 106 106 106 105 104 99.42 

0.225806451612903 105 105 104 103 102 98.21 

0.258064516129032 104 104 103 102 102 97.12 

0.290322580645161 104 104 103 102 101 95.47 

0.32258064516129 102 102 102 101 99.84 95.19 

0.354838709677419 101 101 101 99.62 99.11 95.05 
152 

0.387096774193548 101 101 100 99.61 98.91 94.6 

0.419354838709677 100 99.96 99.52 98.7 98.13 94.09 

0.451612903225806 99.71 99.61 99.22 98.44 97.91 94.06 

0.483870967741936 98.5 98.32 97.67 96.4 95.64 91.79 

0.516129032258065 97.7 97.56 97 96.12 95.57 91.44 

0.548387096774194 97.17 97.04 96.57 95.99 95.37 91.36 

0.580645161290323 96.46 96.34 96.01 95.4 94.93 90.78 

0.612903225806452 96.4 96.12 94.63 93.5 93.01 89.44 

0.645161290322581 94.55 94.49 94.13 91.87 91.64 88.68 

0.67741935483871 92.38 92.34 92.16 91.86 90.34 86.78 

0.709677419354839 91.67 91.61 91.34 90.67 90.19 82.77 

0.741935483870968 86.87 86.81 86.55 86.01 85.65 82.55 

0.774193548387097 82.58 82.52 82.32 81.82 81.45 78.75 

0.806451612903226 59.57 59.4 58.76 58.33 57.81 54.67 

0.838709677419355 51.3 51.14 50.46 49.09 48.31 44.99 

0.870967741935484 36.5 36.33 35.63 34.45 33.78 30.14 

0.903225806451613 31.34 31.32 31.21 30.98 30.82 29.72 

0.935483870967742 20.15 20.06 19.77 19.2 18.87 17.26 

0.967741935483871 13.94 13.84 13.43 12.65 12.22 10.08 

0.1 108.8 108.8 107.9 107.8 106.8 103.8 

 Average of yearly averages: 81.4803333333333 

Inputs generated by pe5.pl - Novemeber 2006 

Data used for this run: 

Output File: acetimp1 

Metfile: w23234.dvf 

PRZM scenario: CAImperviousRLF.txt 

EXAMS environment file: pond298.exv 

Chemical Name: acetamiprid 

Description Variable Name Value Units Comments 

Molecular weight mwt 222.68 g/mol 

Henry's Law Const. henry 5.2E-14 atm-m^3/mol 

Vapor Pressure vapr 7.5E-10 torr 

Solubility sol 4250 mg/L 

Kd Kd mg/L 

Koc Koc 227 mg/L 

Photolysis half-life kdp 34 days Half-life 

Aerobic Aquatic Metabolism kbacw 1974 days Halfife 

Anaerobic Aquatic Metabolism kbacs 4116 days Halfife 

Aerobic Soil Metabolism asm 383 days Halfife 

Hydrolysis: pH 7 0 days Half-life 

Method: CAM 2 integer See PRZM manual 

Incorporation Depth: DEPI 0 cm 

Application Rate: TAPP 0.2622 kg/ha 

Application Efficiency: APPEFF 0.99 fraction 

Spray Drift DRFT 0 fraction of application rate applied to pond 

Application Date Date 01-01 dd/mm or dd/mmm or dd-mm or dd-mmm 

Record 17: FILTRA 

 IPSCND 1 

 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) 
153