Acetamiprid Human Health Risk Assessment 0423298, 0 426 11 5, 0426 11 7, 0427 194 

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, DC 20460 

OFFICE OF CHEMICAL SAFETY AND 

POLLUTION PREVENT ION 

MEMORANDUM 

DATE: 2 September 2015 

SUBJECT: Acetamiprid. Human Health Risk Assessment Addressing Proposed Label 

Amendments for Use of Two End-Use Products (EPs) on Various Crops; 

Proposed ew EP for Controlling Fleas, Ticks and Mosquitoes on Dogs; and a 

Petition Proposing Label Amendments for Two EPs, and Revised Pe rmanent 

Tolerances, for Use of the insecticide on Clover with a Decreased Pre-Harvest 

Interval (Regional Registration). 

PC Code: 099050 OP Ba rcodes: 0423298. 0426115. 0426117. 0427194 

Registra tion Numbers: 8033-20. 8033-23. 8033-36 

File Symbol: 8033-RGR 

Decision Numbers: 494790. 500044. 500022. 495418 

Petition: 4E8307 Regulatory Action: Section 3 

Risk Assessment Type: Single Chemica l. Aggregate 

T XR Number: NA 

Case Number: 76 17 

CAS Number: 1354 10-20-7 

MRID Numbers: 4944380 I. 49443802 40 C FR: § 180.578 

FROM: 

THRU: 

TO: 

and 

William T. Drew. Chemist 

Karlyn Middleton, Toxicologist ~ 

Risk Assessment Branch II (RAB2 · /1 j j 

Joshua Godshall, Biologist Q.... ~l/\ 

Risk Assessment Branch I (RAB t'f 

Health Effects Division (HED). 7509P 

Elizabeth Holman, PhysicJ,.I foej~nti s~ ~ ~ Christina Swartz, Chief ~ ~ 

RAB2 

HED. 7509P 

Barbara Madden and Sidney Jackson, RM Team 05 

Minor Use and Emergency Response Branch (MUERB) 

Registration Division (RD), 7505P 

Page I of 49 
Acetamiprid Human Health Risk Assessment 0423298, 0426115, 0426117, 0427194 

and 

Venus Eagle and Jacquelyn Marchese, RM Team 0 I 

I nvertebrate-V crtebrale Branch 3 (TV B3) 

RD, 7505P 

Je1rnifer Urbanski and Elizabeth Fertich, RM Team 04 

Invertebrate-Vertebrate Branch 1 (IV BI) 

RD, 7505P 

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Acetamiprid Human Health Risk Assessment D423298, D426115, D426117, D427194

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Table of Contents

1.0 Executive Summary ..........................................................................................................................4

2.0 HED Recommendations....................................................................................................................5

2.1 Data Deficiencies/Conditions of Registration...............................................................................6

2.2 Tolerance Considerations..............................................................................................................6

2.2.1 Enforcement Analytical Method...........................................................................................6

2.2.2 International Harmonization .................................................................................................6

2.2.3 Recommended Tolerances....................................................................................................7

2.2.4 Revisions to Petitioned-For Tolerances................................................................................7

2.3 Label Recommendations...............................................................................................................7

3.0 Introduction.......................................................................................................................................8

3.1 Chemical Identity..........................................................................................................................8

3.2 Physical/Chemical Characteristics................................................................................................8

3.3 Pesticide Use Pattern.....................................................................................................................8

3.4 Anticipated Exposure Pathways..................................................................................................12

3.5 Consideration of Environmental Justice .....................................................................................13

4.0 Hazard Characterization and Dose-Response Assessment .............................................................13

4.1 Summary of Toxicology Database and Toxicological Effects....................................................13

4.2 Safety Factor for Infants and Children (FQPA Safety Factor)....................................................16

4.2.1 Completeness of the Toxicology Database .........................................................................16

4.2.2 Evidence of Neurotoxicity ..................................................................................................16

4.2.3 Evidence of Sensitivity/Susceptibility in the Developing or Young Animal......................16

4.2.4 Residual Uncertainty in the Exposure Database .................................................................17

4.3 Toxicity Endpoint and Point of Departure Selections.................................................................18

5.0 Dietary Exposure and Risk Assessment..........................................................................................21

5.1 Metabolite/Degradate Residue Profile ........................................................................................21

5.2 Food Residue Profile...................................................................................................................21

5.3 Water Residue Profile .................................................................................................................23

5.4 Dietary Risk Assessment ............................................................................................................23

6.0 Residential (Non-Occupational) Exposure/Risk Characterization..................................................24

6.1 Spray Drift ..................................................................................................................................28

7.0 Aggregate Exposure/Risk Characterization ....................................................................................29

7.1 Acute Aggregate Risk .................................................................................................................29

7.2 Short- and Intermediate-Term Aggregate Risk...........................................................................29

7.3 Chronic Aggregate Risk..............................................................................................................30

7.4 Cancer Aggregate Risk ...............................................................................................................31

8.0 Cumulative Exposure/Risk Characterization ..................................................................................31

9.0 Occupational Exposure/Risk Characterization ...............................................................................31

9.1 Short-, Intermediate- and Long-Term Handler Risk...................................................................32

9.2 Short- and Intermediate-Term Post-Application Risk ................................................................36

9.2.1 Dermal Post-Application Risk ............................................................................................36

9.2.2 Inhalation Post-Application Risk........................................................................................40

10.0 References.......................................................................................................................................40

Appendix A. Toxicology Profile and Executive Summaries.....................................................................42

Appendix B. Physicochemical Properties.................................................................................................. 49
Acetamiprid Human Health Risk Assessment D423298, D426115, D426117, D427194

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1.0 Executive Summary

Acetamiprid (CAS name (1E)-N-[(6-chloro-3-pyridinyl)methyl]-N′-cyano-Nmethylethanimidamide) is a selective insecticide intended for use against various sucking and 

chewing insect pests that feed upon fruit and vegetable crops. It is a member of the 

chloronicotinyl (neonicotinoid) class of insecticides, which function by binding to nicotinic 

acetylcholine receptors in the post-synaptic neurons of the insect’s central nervous system. This 

binding results in the opening of ion pores, causing a subsequent overload of sodium ions in the 

neurons which leads to nervous system hyper-excitation, and the eventual death of the insect. 

Acetamiprid is registered for use on a variety of crops, and permanent tolerances have been 

established ranging from 0.010 ppm to 50 ppm in plant commodities (40 CFR §180.578[a][1]), 

and from 0.010 ppm to 0.70 ppm in livestock commodities (40 CFR §180.578[a][2]). There are 

also permanent tolerances (with regional registrations) established in clover forage at 0.10 ppm, 

and clover hay at 0.01 ppm (40 CFR §180.578[c]). The residue definition for risk assessment 

and tolerance enforcement is the parent compound in plant commodities, and combined residues 

of the parent compound and Metabolite IM-2-1 in livestock commodities (plus Metabolite IM-2-

1-amide in ruminant muscle for risk assessment purposes only). Acceptable analytical methods 

are available to enforce tolerances for residues of acetamiprid in plant and livestock 

commodities. This risk assessment addresses 3 separate registration requests, consisting of a 

proposed increase in tolerances for residues in clover commodities, label amendments for 

existing agricultural uses, and a new spot-on product for use on dogs, as described below. 

Interregional Research Project #4 (IR-4) has submitted a petition (4E8307) requesting an 

amended use pattern, and revised tolerances in clover forage and hay, for use of acetamiprid on 

clover grown for seed in ID, OR and WA only. The proposed pre-harvest interval (PHI) is 30 

days for clover, compared to the currently registered PHI of 56 days. The end-use products 

(EPs) proposed for regional registration are Assail 70WP Insecticide (EPA Registration #8033-

23), a wettable powder (WP) formulation containing 70% of the active ingredient (ai) by weight, 

and Assail 30SG Insecticide (EPA Registration #8033-36), a soluble granule (SG) formulation 

containing 30% of the ai by weight. 

IR-4 submitted field trial data for acetamiprid on clover grown for seed in response to an Agency 

request for two additional clover field trials as confirmatory data (D364833; D. McNeilly; 14 

October 2009). In conjunction with the petition, IR-4 has proposed the revision of established 

tolerances for residues of acetamiprid in or on clover forage (from 0.10 to 0.3 ppm) and clover 

hay (from 0.01 to 1.5 ppm), with regional registration (in ID, OR and WA only). The proposed 

tolerance in clover forage is supported adequately by the current submitted field trial residue 

data, in conjunction with previously submitted field trial data (D364833; D. McNeilly; 14 

October 2009). The current submitted field trial residue data support the recommended 

tolerances of 2.0 ppm in clover hay, and 0.30 ppm in clover forage. 

Also, Nippon Soda Company Limited (care of Nisso America Incorporated) has proposed 

multiple label amendments (D426115 and D426117) for revised use patterns of the same 
Acetamiprid Human Health Risk Assessment D423298, D426115, D426117, D427194

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acetamiprid EPs (Assail 70WP and Assail 30SG) on various crops. These amendments do not 

require the revision of any existing acetamiprid tolerances. 

Additionally, Nippon Soda has proposed a new EP, RF2213 AE CDSO Insecticide (EPA File 

Symbol 8033-RGR) for controlling fleas, ticks and mosquitoes on dogs. The RF2213 AE CDSO

Insecticide contains 9.5% acetamiprid, 20.0% etofenprox, 8.0% piperonyl butoxide, and 5.0% 

s-methoprene. This assessment addresses exposure and risk associated with the use of 

acetamiprid only; it does not address etofenprox, piperonyl butoxide, or s-methoprene exposure 

associated with the use of this product. 

HED has evaluated the hazard information, proposed labels, and residue data for these revised or 

new uses, and assessed risk associated with occupational, residential, dietary and aggregate 

exposures. Risk estimates based on screening level, upper-bound inputs are below HED’s level 

of concern (LOC) for all scenarios and population subgroups, including those of infants and 

children. 

This risk assessment has taken into consideration potential environmental justice issues. Based 

on the existing and proposed uses for acetamiprid, and on current Office of Pesticide Programs 

(OPP) assessment policies, there are no environmental justice concerns associated with 

acetamiprid.

There are no human health risk concerns that would preclude granting the requested uses, and 

establishing increased tolerances for residues of acetamiprid in clover. 

This risk assessment relies in part on data from studies in which adult human subjects were 

intentionally exposed to a pesticide or other chemical. These studies, which comprise the 

Occupational Pesticide Handlers Exposure Database (OPHED, available at the EPA internet sites

http://www.epa.gov/pesticides/science/handler-exposure-data.html and 

http://www.epa.gov/pesticides/science/post-app-exposure-data.html), have been determined to 

require a review of their ethical conduct, have received that review, and have been determined to 

have been ethically conducted.

2.0 HED Recommendations

HED has examined the residue chemistry database for acetamiprid. Pending submission of a 

revised Section F (to propose tolerances in clover forage and hay in accordance with HED’s 

recommendations), there are no residue chemistry issues that would preclude increasing the 

established tolerances to the recommended levels. The recommended tolerances are listed in 

Table 2.2.3, below. 

HED has no objection regarding the proposed label amendments for revised use patterns of the 

acetamiprid EPs, Assail 70WP and Assail 30SG, on various crops. HED also has no objection to 

the proposed use on dogs to control fleas, ticks and mosquitoes. 
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Notes to RD: 

1) An error has been identified with a commodity definition in the existing 

40CFR entry for acetamiprid, which currently lists “Vegetable, tuberous 

and corm, group 1” under 40CFR §180.578[a][1]. This listing should be 

revised to read “Vegetable, tuberous and corm, subgroup 1C” when the 

tolerances for clover forage and hay are revised. 

2) The analytical reference standard for acetamiprid metabolite IM-1-4 (having 

expired on 1 April 2015) is currently unavailable in EPA’s National 

Pesticide Standards Repository (NPSR), per Email communication from 

Theresa Cole of the Biological and Economic Analysis Division’s 

Analytical Chemistry Branch (BEAD/ACB) on 1 June 2015. RD should 

notify the registrant (Nisso America Incorporated) regarding this lack of a 

reference standard for metabolite IM-1-4, and request that the registrant 

provide a new reference standard, or updated certificate of analysis 

(COA), as soon as possible. 

3) In order to assess post-application exposure for workers contacting treated 

cotton, HED relied on a chemical-specific study for tribufos; use of the 

surrogate study may result in data compensation issues for the registrants. 

2.1 Data Deficiencies/Conditions of Registration

None. 

2.2 Tolerance Considerations

2.2.1 Enforcement Analytical Method

Approved tolerance enforcement methods for acetamiprid residues in crops are available, 

including gas chromatography with electron capture detection (GC/ECD) for vegetables and 

non-citrus fruits, high performance liquid chromatography with ultraviolet detection (HPLC/UV) 

for citrus fruits only, and HPLC with tandem mass spectrometric detection (LC/MS/MS) for 

vegetables and non-citrus fruits. Two of these methods are adequate for enforcing the proposed 

tolerances associated with this petition. 

2.2.2 International Harmonization

Codex has not established maximum residue limits (MRLs) for acetamiprid in clover forage or 

hay. Canada’s Pest Management Regulatory Agency (PMRA) does not establish MRLs in 

livestock feed items. Ergo, there are no issues with international harmonization that need to be 

addressed. 
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2.2.3 Recommended Tolerances

The currently established tolerance expressions for acetamiprid (40CFR §180.578) are adequate, 

and include both coverage and compliance statements for enforcement purposes. 

Note to RD: An error has been identified with a commodity definition in the existing 40CFR 

entry for acetamiprid, which currently lists “Vegetable, tuberous and corm, group 1” under 

40CFR §180.578[a][1]. This listing should be revised to read “Vegetable, tuberous and corm, 

subgroup 1C” when the tolerances for clover forage and hay are revised. 

TABLE 2.2.3 Tolerance Summary for Acetamiprid (40CFR §180.578[c]). 

Commodity Existing 

Tolerance (ppm)

Proposed 

Tolerance (ppm)

Recommended 

Tolerance (ppm)1

Correct Commodity Definition; 

Comments

Clover, forage 0.102 0.3 0.30 Based on current and previous clover 

field trial data submitted by IR-4. 

Clover, hay 0.01

2 1.5 2.0 Based on current clover field trial 

data submitted by IR-4.

1. Tolerance level as recommended by HED. 

2. A tolerance is currently established at the listed tolerance level in the corresponding commodity. 

2.2.4 Revisions to Petitioned-For Tolerances

The submitted clover field trial data support a tolerance of 2.0 ppm, instead of the proposed 

tolerance of 1.5 ppm, in clover hay. The petitioner used residues in clover hay from all field 

trials to calculate the tolerance level (PHIs of 27-63 days). The draft labels stipulate a PHI of 30 

days (decreased from 56 days on the current labels). Therefore, only residues from those trials 

where hay was collected at PHIs of 27-32 days were used to calculate the tolerance; residues 

from those trials where hay was collected at PHIs of 50-63 days were not used. HED utilized 

residue data for hay collected at PHIs of 27-32 as the input dataset for the Organization for 

Economic Cooperation and Development (OECD) tolerance calculation procedure, yielding a 

different result (2.0 ppm). 

In clover forage, the recommended tolerance level includes an additional significant figure (0.30 

ppm rather than 0.3 ppm). This is in order to avoid the situation where rounding of a residue 

result to the level of precision of the tolerance expression would be considered non-violative 

(such as 0.34 ppm being rounded to 0.3 ppm). 

The petitioner should submit a revised Section F, specifying the recommended tolerances in 

Table 2.2.3 (above). 

 

2.3 Label Recommendations

None. 
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3.0 Introduction

Acetamiprid is a selective insecticide intended for use against various sucking/chewing insect 

pests that feed upon fruit and vegetable crops. It is a member of the chloronicotinyl 

(neonicotinoid) class of insecticides, which function by binding to nicotinic acetylcholine 

receptors in the post-synaptic neurons of the insect’s central nervous system. This binding 

results in the opening of ion pores, causing a subsequent overload of sodium ions in the neurons 

which leads to nervous system hyper-excitation, and eventual death of the insect. The chemical 

structure and nomenclature of acetamiprid are listed in Table 3.1 (below). 

3.1 Chemical Identity

TABLE 3.1 Acetamiprid Nomenclature.

Chemical Structure

Common Name Acetamiprid

Molecular Formula C10H11ClN4

Molecular Weight 222.68

Company Experimental Name EXP-61842A, AEF124370, NI-25

IUPAC Name (E)-N 1-[(6-chloro-3-pyridyl)methyl]-N

2

-cyano-N 1-methylacetamidine

CAS Name (1E)-N-[(6-chloro-3-pyridinyl)methyl]-N'-cyano-N-methylethanimidamide

CAS Registry Number 135410-20-7

End-use Products (EPs) Assail 70WP (70% WP; EPA Registration #8033-23)

Assail 30SG (30% SG; EPA Registration #8033-36)

RF2213 AE CDSO Insecticide (9.5% Spot-on; EPA File Symbol 8033-RGR)

3.2 Physical/Chemical Characteristics

The physicochemical properties of technical-grade acetamiprid are summarized in Appendix B. 

The values in the table suggest that there are no exposure scenarios that are likely to require 

special consideration. The vapor pressure for acetamiprid is quite low and, as such, inhalation 

exposure via volatilization is expected to be negligible. The octanol/water partition coefficient 

indicates that partitioning into fatty tissues is unlikely, and that there is low potential for 

bioaccumulation. 

3.3 Pesticide Use Pattern

IR-4 has proposed an amended use pattern, and revised tolerances in clover forage and hay, for 

foliar broadcast use of the insecticide acetamiprid on clover grown for seed in ID, OR and WA 

only. The proposed PHI is 30 days for clover, compared to the currently registered PHI of 56 

days. The EPs proposed for regional registration are Assail 70WP Insecticide (EPA Registration 

N N

CH3

Cl

CH3

N

CN
Acetamiprid Human Health Risk Assessment D423298, D426115, D426117, D427194

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#8033-23), a WP formulation containing 70% of the ai by weight, and Assail 30SG Insecticide 

(EPA Registration #8033-36), an SG formulation containing 30% of the ai by weight. Examples 

of the proposed labels were provided, and the proposed revision of the use directions therein are 

summarized in Table 3.3.1, below. 

TABLE 3.3.1 Summary of Proposed Label Directions for Use of Acetamiprid on Clover. 

Application 

Timing; Type; 

Equipment1

Use Rate 

(lb ai/A)

Max. Uses 

per Season

Maximum 

Seasonal Use 

Rate (lb ai/A)

PHI2

(Days)

Use Directions and Limitations

Assail 70WP

Post-emergence; 

foliar broadcast; 

ground, aerial

0.05-

0.075

1

3 0.075 30 Minimum spray volume of 5 GPA4 by 

air, or 20 GPA by ground. Begin 

applications when treatment thresholds 

have been reached. Thorough coverage 

is important to obtain optimum control. 

Assail 30SG

Post-emergence; 

foliar broadcast; 

ground, aerial

0.047-

0.075

1

3 0.075 30 Minimum spray volume of 5 GPA by 

air, or 20 GPA by ground. Begin 

applications when treatment thresholds 

have been reached. Thorough coverage 

is important to obtain optimum control. 

1. Not to be applied via chemigation. 

2. PHI = Pre-Harvest Interval. 

3. Implied; more than 1 application at the minimum single use rate would exceed the maximum seasonal use rate. 

4. GPA = Gallons Per Acre. 

Conclusion: The use directions for application to clover are sufficient to allow for evaluation of 

the submitted residue data relative to the proposed use pattern. 

Nisso America has also proposed multiple label amendments for revised use patterns of the same 

acetamiprid EPs (Assail 70WP and Assail 30SG) on various crops. The requested revisions 

increase single (but not seasonal) use rates, add pests, and make additional minor changes to the 

EP labels. These label revisions do not change the amount of ai applied per acre per year, and no 

revisions to tolerances were proposed by the registrant. Required personal protective equipment 

(PPE) for Assail 30 SG and Assail 70 WP Insecticides include long sleeved shirts, long pants, 

shoes plus socks, chemical resistant gloves, and chemical resistant headgear for overhead 

exposure. In addition, for aerial applications only, assail 70WP Insecticide requires 

mixers/loaders to wear a dust/mist filtering respirator. Both labels incorporate a 12 hour 

restricted entry interval (REI). Examples of the proposed labels were provided, and the proposed

use pattern revisions therein are summarized in Table 3.3.2, below. 
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TABLE 3.3.2 Summary of Proposed Amendments to Label Directions for Use of Acetamiprid. 

Crop Pest Current 

Use Rate

(lb ai/A)

Proposed 

Use Rate

(lb ai/A)

Amendments to Use Directions and 

Limitations

Assail 70WP (EPA Registration #8033-23)

Cotton Whitefly 0.075-

0.10

0.075-

0.15

To “Do not make more than 4 applications per 

season,” add “or more than 2 applications per 

season if 2 applications of the highest labeled rate 

is applied for both applications.” 

Leafy 

Vegetables 

(within Crop 

Group 4)

Aphid 0.035-

0.075

0.035-

0.10

To “Do not make more than 5 applications per 

season,” add “or more than 3 applications per 

season if 3 applications of the highest labeled rate 

is applied for all 3 applications.” 

Whitefly 0.05-

0.075

0.05-0.10

Head and Stem 

Cole Crops 

(within Crop 

Subgroup 5A)

NA1 NA NA Change “Head and Stem Cole Crops (within 

Crop Subgroup 5A)” to “Head and Stem Brassica

(within Crop Subgroup 5A).” 

Leafy Cole 

Crops (within 

Crop Subgroup 

5B)

NA NA NA Change “Leafy Cole Crops (within Crop 

Subgroup 5B)” to “Leafy Brassica (within Crop 

Subgroup 5B).” 

Fruiting 

Vegetables 

(within Crop 

Group 8-10)

Leafhopper2 NA 0.05-

0.075

Add “Begin applications when treatment 

thresholds have been reached. Thorough 

coverage is important to obtain optimum 

control.” to the use directions for the new target 

pest, leafhopper. 

Citrus (within 

Crop Group 10-

10)

Asian Citrus Psyllid NA NA Add “(suppression)” note to this target pest. 

Apple Maggot, Plum 

Curculio, San Jose 

Scale

Remove “(suppression)” note from these target 

pests. 

Grapes (within 

Crop SubGroup 13-07F)

All target pests NA NA Remove “For ASSAIL WSP Insecticide Only (1 

to 2 packets)” from dosage per acre. Change 

“WSP” to “70WP” in mealybugs use directions. 

Remove “Do not use adjuvants.” from 

restrictions.

Cucurbits 

(within Crop 

Group 9)

Whitefly 0.05-0.10 0.05-0.15 To “Do not make more than 5 applications per 

season,” add “or more than 3 applications per 

season if 3 applications of the highest labeled rate 

is applied for all 3 applications.” To “Do not 

apply less than 0 days before harvest (PHI=0 

days),” add “with application rate of 2.3 oz/A or 

less.” Add “Do not apply less than 5 days before 

harvest (PHI=5 days) with application rate of 3.5 

oz/A.” to restrictions. 

Legume 

Vegetables 

(within Crop 

Sub-Groups 6A 

and 6B)

Colorado Potato 

Beetle2

NA 0.044-

0.10

Add “Colorado Potato Beetle: Use higher rates 

when populations are high, dense foliage exists, 

or when large larvae or adults are present. 

Thorough coverage is important to obtain 

optimum control.” to use directions. 
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TABLE 3.3.2 Summary of Proposed Amendments to Label Directions for Use of Acetamiprid. 

Crop Pest Current 

Use Rate

(lb ai/A)

Proposed 

Use Rate

(lb ai/A)

Amendments to Use Directions and 

Limitations

Berries (within 

Crop SubGroups 13-07A 

and 13-07B)

EAST of Rocky 

Mountains Only.

Spotted Winged

Drosophila (larvae)2

NA 0.085-

0.10

Add “Spotted Winged Drosophila (larvae): Begin 

applications when adults are present and fruit is 

ripening or already ripe. It is recommended to 

tankmix with an adulticide.” to use directions. 

Assail 30SG (EPA Registration #8033-36)

Cotton Whitefly 0.075-

0.10

0.075-

0.15

To “Do not make more than 4 applications per 

season,” add “or more than 2 applications per 

season if 2 applications of the highest labeled rate 

is applied for both applications.” 

Leafy 

Vegetables 

(within Crop 

Group 4)

Aphid 0.038-

0.075

0.038-

0.10

To “Do not make more than 5 applications per 

season,” add “or more than 3 applications per 

season if 3 applications of the highest labeled rate 

is applied for all 3 applications.” 

Whitefly 0.056-

0.075

0.056-

0.10

Head and Stem 

Cole Crops 

(within Crop 

Subgroup 5A)

NA NA NA Change “Head and Stem Cole Crops (within 

Crop Subgroup 5A)” to “Head and Stem Brassica

(within Crop Subgroup 5A).” 

Leafy Cole 

Crops (within 

Crop Subgroup 

5B)

NA NA NA Change “Leafy Cole Crops (within Crop 

Subgroup 5B)” to “Leafy Brassica (within Crop 

Subgroup 5B).” 

Fruiting 

Vegetables 

(within Crop 

Group 8-10)

Leafhopper2 NA 0.047-

0.075

Add “Begin applications when treatment 

thresholds have been reached. Thorough 

coverage is important to obtain optimum 

control.” to the use directions for the new target 

pest, leafhopper. 

Citrus (within 

Crop Group 10-

10)

Asian Citrus Psyllid NA NA Add “(suppression)” note to this target pest. 

Grapes (within 

Crop SubGroup 13-07F)

All target pests NA NA Remove “Do not use adjuvants.” from 

restrictions.

Cucurbits 

(within Crop 

Group 9)

Whitefly 0.047-

0.10

0.047-

0.15

To “Do not make more than 5 applications per 

season,” add “or more than 3 applications per 

season if 3 applications of the highest labeled rate 

is applied for all 3 applications.” To “Do not 

apply less than 0 days before harvest (PHI=0 

days),” add “with application rate of 5.3 oz/A or 

less.” Add “Do not apply less than 5 days before 

harvest (PHI=5 days) with application rate of 8.0 

oz/A.” to restrictions. 

Legume 

Vegetables 

(within Crop 

Sub-Groups 6A 

and 6B

Colorado Potato 

Beetle2

NA 0.047-

0.10

Add “Colorado Potato Beetle: Use higher rates 

when populations are high, dense foliage exists, 

or when large larvae or adults are present. 

Thorough coverage is important to obtain 

optimum control.” to use directions. 
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TABLE 3.3.2 Summary of Proposed Amendments to Label Directions for Use of Acetamiprid. 

Crop Pest Current 

Use Rate

(lb ai/A)

Proposed 

Use Rate

(lb ai/A)

Amendments to Use Directions and 

Limitations

Berries (within 

Crop SubGroups 13-07A 

and 13-07B)

EAST of Rocky 

Mountains Only.

Spotted Winged

Drosophila (larvae)2

NA 0.085-

0.10

Add “Spotted Winged Drosophila (larvae): Begin 

applications when adults are present and fruit is 

ripening or already ripe. It is recommended to 

tankmix with an adulticide.” to use directions. 

1. NA = Not Applicable. 

2. New pest added to the list of target pests. 

Conclusions: Based on risk estimates for the proposed higher single application rates, HED has 

no objection regarding the proposed amendments to the labels’ use directions. 

Additionally, Nippon Soda has proposed a new spot-on EP, RF2213 AE CDSO Insecticide (EPA 

File Symbol 8033-RGR) for controlling fleas, ticks and mosquitoes on dogs. The RF2213 AE 

CDSO Insecticide contains 9.5% acetamiprid. An example of the proposed label was provided, 

and the proposed use pattern revisions therein are summarized in Table 3.3.3, below. 

TABLE 3.3.3 Summary of Proposed Label Directions for Spot-On Use of Acetamiprid on Dogs.

Use Site Maximum Use Rate Per Dog Use Restrictions

Toy/small dogs(4 to 

9 lbs)

0.8 ml applicator tube (0.027 fl oz)

80 mg ai/treatment1(0.00018 lb ai 

/treatment)

2

Do not use on dogs less than 6 months old. Do 

not use more than one cartridge per dog. Do not 

treat more than once per month (30 days). Do 

not apply to dogs weighing less than 4 lbs. 

Apply directly to the dog’s skin, not to the hair. Medium dogs (10 to 

22 lbs)

2.0 ml applicator tube (0.068 fl oz)

203.5 mg ai/treatment1(0.00045 lb ai 

/treatment)

2

Large dogs (23 to 55 

lbs)

5.0 ml applicator tube (0.169 fl oz)

505.8 mg ai/treatment1(0.0011 lb ai 

/treatment)

2

Extra-large dogs (≥ 

56 lbs)

8.0 ml applicator tube (0.271 fl oz)

811 mg ai/treatment1(0.0018 lb ai 

/treatment)

2

1. Use rate in mg ai/treatment = [(fl oz product) × (0.84455 lbs ai/gal) ÷ (128 fl oz/gal) × (453592.37 mg/lb)]. 

2. Based on the proposed label for the requested spot-on use of RF2213 AE CDSO Insecticide EPA File Symbol 

8033-RGR. [(fl oz product × 0.84455 lb ai/gal) ÷ 128 fl oz/gal]. 

Conclusions: HED has no objection to registration of the proposed new spot-on EP. 

3.4 Anticipated Exposure Pathways

Acetamiprid is registered for use on growing crops, as well as in and around the home. As a 

result of the uses on crops, as well as a recently proposed and assessed use in food/feed handling 

establishments, humans may be exposed to acetamiprid in food and drinking water. In addition, 

exposure may occur in residential or non-occupational settings. In an occupational setting, 

applicators may be exposed while handling the pesticide prior to application, as well as during 
Acetamiprid Human Health Risk Assessment D423298, D426115, D426117, D427194

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application. There is also a potential for post-application exposure for workers re-entering 

treated fields. 

Risk assessments have been previously prepared for the existing uses of acetamiprid. This risk 

assessment considers all of the aforementioned exposure pathways based on the proposed new 

uses of acetamiprid, and also considers the existing uses, particularly for dietary exposure. 

3.5 Consideration of Environmental Justice

Potential areas of environmental justice concerns, to the extent possible, were considered in this 

human health risk assessment, in accordance with US Executive Order 12898, "Federal Actions 

to Address Environmental Justice in Minority Populations and Low-Income Populations" (at the 

internet site http://www.eh.doe.gov/oepa/guidance/justice/eo12898.pdf). As a part of every 

pesticide risk assessment, OPP considers a large variety of consumer subgroups according to 

well-established procedures. In line with OPP policy, HED estimates risks to population 

subgroups from pesticide exposures that are based on patterns of that subgroup’s food and water 

consumption, and activities in and around the home that involve pesticide use in a residential 

setting. Extensive data on food consumption patterns are compiled from the US Department of 

Agriculture’s National Health and Nutrition Examination Survey, What We Eat in America, 

(NHANES/WWEIA), and are used in pesticide risk assessments for all registered food uses of a 

pesticide. These data are analyzed and categorized by subgroups based on age, season of the 

year, ethnic group, and region of the country. Additionally, OPP is able to assess dietary 

exposure to smaller, specialized subgroups and exposure assessments are performed when 

conditions or circumstances warrant. Whenever appropriate, non-dietary exposures based on 

home use of pesticide products, and associated risks for adult applicators and for toddlers, youths

and adults entering or playing on treated areas post-application are evaluated. Further 

considerations are currently in development as OPP has committed resources and expertise to the 

development of specialized software and models that consider exposure to bystanders and farm 

workers, as well as lifestyle and traditional dietary patterns among specific subgroups.

4.0 Hazard Characterization and Dose-Response Assessment

Comprehensive risk assessments for acetamiprid were conducted in 2013 (D410182; E. Holman; 

20 March 2013). For this assessment, no changes have been made regarding endpoint selection 

for dietary exposure (acute and chronic) nor short -and intermediate term incidental oral, dermal, 

or inhalation exposure. However, endpoints and points of departure (PODs) have been selected 

for long-term scenarios (incidental oral and dermal) since long term exposure is anticipated 

based on the proposed pet use. 

 

4.1 Summary of Toxicology Database and Toxicological Effects

The database for acetamiprid is considered complete. An inhalation study is not available for 

acetamiprid. However, the Hazard Science Policy Council (HASPOC) previously determined 
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that the study is not needed (TXR 0056556; K. Rury; 20 February 2013). Consequently, the 10X 

database uncertainty factor retained in the 2012 assessment for inhalation scenarios has been 

removed, with the LOC being lowered to 100 for these scenarios. The toxicity database for 

acetamiprid contains:

1) Subchronic oral toxicity studies in rats, mice and dogs; 

2) a chronic oral toxicity study in dogs, and carcinogenicity studies in rats and 

mice; 

3) developmental and reproduction studies in rats, and a developmental study in 

rabbits; 

4) acute, subchronic and developmental neurotoxicity studies in rats; 

5) immunotoxicity studies in rats and mice; and

6) subchronic dermal toxicity and dermal penetration studies in rats. 

There is also a complete mutagenicity battery, as well as metabolism studies in the rat. No 

literature information is available that would have an impact upon risk assessment. Metabolites 

were only examined in some mutagenicity studies. 

In all species tested, generalized nonspecific toxicity was observed as decreases in body weight, 

body weight gain, food consumption, and food efficiency. Generalized effects were also 

observed in the liver in the form of hepatocellular hypertrophy in both mice and rats, and 

hepatocellular vacuolation in the rat. These effects are considered to be adaptive. Other effects 

observed in the oral studies include amyloidosis of multiple organs in the mouse oncogenicity 

study, tremors in high dose females in the mouse subchronic study, and microconcretions in the 

kidney papilla, and mammary hyperplasia in the rat chronic/oncogenicity study. 

No effects were observed in the 21-day dermal study in the rabbit, and no inhalation studies were 

conducted. A dermal absorption study with acetamiprid was conducted using male rats with 

exposure durations up to 24 hours. In some earlier acetamiprid risk assessments, a 30% dermal 

absorption value was estimated from this study. However, HED has refined the dermal 

absorption value (to 10%), based upon comparison to clothianidin, which is structurally related. 

Acetamiprid is rapidly absorbed and eliminated. Metabolism studies indicate 96-99% absorption 

following an oral administration. Peak blood concentrations in the rat occur within 1-2 hours, 

with nearly complete clearance from the blood by 48 hours. Acetamiprid distributes widely in 

the body but tissue burdens rarely exceed 1% of the administered dose. Acetamiprid is 

extensively metabolized, with metabolites accounting for 79-86% of the administered 

radioactivity. 6-Chloronicotinic acid is the most abundant metabolite, accounting for 24-28% of 

the dose in single-dose studies, and 8-10% in repeated-dose studies. Urinary excretion was the 

major route of elimination, accounting for 79-97% of the administered dose within 24 hours in 

single oral dose groups. Fecal excretion accounted for 21-35% of the administered radioactivity, 

with males being slightly higher. Excretion rates for the IV and repeated dose studies were 

similar. Biliary excretion did not vary between genders, and by 48 hours accounted for about 

19% of the administered radioactivity. 
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There was no evidence of increased quantitative or qualitative susceptibility of rat or rabbit 

fetuses to in utero exposure in the developmental studies. 

In the 2-generation reproduction study, qualitative evidence of increased susceptibility of rat 

pups was observed. The parental and offspring systemic effects were based on a decrease in 

mean body weight, body weight gain, and food consumption in the parents, and significant 

reductions in pup weights in both generations. Also observed were reduction in litter size and 

viability and weaning indices among F2 offspring, as well as significant delays in the age to 

attain vaginal opening and preputial separation. These offspring observations were considered to 

be more severe than the parental effects. 

In the developmental neurotoxicity (DNT) study, there was also evidence of increased qualitative 

susceptibility. In this study, the offspring lowest observed adverse effect level (LOAEL) was 

based on decreased body weights and body weight gains in males and females, decreased preweaning survival on post-natal days (PNDs) 0-1, and decreased maximum auditory startle 

response in males on PNDs 20 and 60. This was observed in the presence of decreased maternal 

body weight and body weight gains during gestation. Although offspring and maternal effects 

were observed at the same doses, the offspring effects were considered to be more severe. 

In a rat acute neurotoxicity study, a decrease in locomotor activity was observed in both sexes on 

the day of dosing. A slight decrease in the duration of movements persisted in some males 

during later observations. Functional observational battery evaluations revealed several 

treatment-related observations on the day of dosing. At the high dose only, males exhibited 

tremors, difficulty in handling, walking on toes, dilated pupils, coldness to the touch, as well as

decreased forelimb grip strength and hind limb foot splay. High-dose females displayed tremors, 

chewing, coldness to the touch, dilated pupils, decreased hind limb foot splay, and abnormal 

gaits and/or posture, including walking on toes and hunched posture. This was not noted in a 

subchronic rat neurotoxicity study. No neuropathology was observed in any of the neurotoxicity 

studies. Tremors in high dose female mice in the subchronic feeding study were the only other 

potentially neurotoxic effect observed in any other studies. 

Four-week immunotoxicity studies were performed for both sexes in rats and mice. No effects 

on the immune system were observed in either species up to the highest dose tested. Significant 

reductions in body weight and body weight gain were noted at that dose. 

Acetamiprid did not show clear evidence of genotoxic potential. It was positive as a clastogen in 

an in vitro mammalian chromosome aberration assay in Chinese hamster ovary (CHO) cells. 

However, the in vivo chromosomal aberration study does not support the results of the in vitro 

study. Acetamiprid metabolites IC-0, IM-1-2, IM-1-4, IM-2-1 and IM-0 tested negative for 

mutagenicity.
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Acute lethality studies conducted with acetamiprid indicated that it is moderately toxic via the 

acute oral route (Category II); however, it has low toxicity via the acute dermal or inhalation 

routes (Categories III). It is non-irritating to the eyes and skin, and is not a dermal sensitizer. 

4.2 Safety Factor for Infants and Children (FQPA Safety Factor)

HED previously recommended the 10X Food Quality Protection Act (FQPA) Safety Factor (SF)

be reduced to 1X for the following reasons: The toxicology data base is complete for the 

purpose of the FQPA assessment; HED is regulating the use of acetamiprid based upon the 

effects of concern, such as developmental effects in pups following pre- and/or post-natal 

exposure; the rat is the most sensitive species tested, and the no observed adverse effect level 

(NOAEL) and LOAEL selected from the DNT study in rats are protective of effects observed in 

other species throughout the toxicology database; there are no residual uncertainties for preand/or post-natal toxicity; the exposure databases (dietary food, drinking water, and residential) 

are complete; and the risk assessment for each potential exposure scenario includes all 

metabolites and/or degradates of concern, and does not underestimate the potential risk to infants 

or children. 

4.2.1 Completeness of the Toxicology Database

As summarized in Appendix Table A1, the toxicology database is considered adequate for the 

purpose of assessing pre- and post-natal susceptibility, including an immunotoxicity study. 

Acceptable developmental toxicity studies in the rat and rabbit, and a rat reproductive toxicity 

study have been submitted. Based on a weight of evidence (WOE) approach considering all the 

available hazard and exposure information, and proposed addition of a respirator for mixing

and/or loading of the WP formulation for aerial application, or other appropriate mitigation, 

HED’s HASPOC concluded that a subchronic inhalation toxicity study is not required for 

acetamiprid at this time (TXR# 0056556). 

4.2.2 Evidence of Neurotoxicity

Acetamiprid produced signs of neurotoxicity in the high dose groups in the acute and 

developmental neurotoxicity studies in rats. In the acute neurotoxicity study, male and female 

rats displayed decreased motor activity, tremors, walking and posture abnormalities, dilated 

pupils, coldness to the touch, and decreased grip strength and foot splay. However, no 

neurotoxic findings were reported in the subchronic neurotoxicity study. There was a decrease 

in the auditory startle response in male rats in the DNT. Tremors in the high dose female mice in 

the subchronic feeding study were the only other potentially neurotoxic effect observed in the 

other studies. 

4.2.3 Evidence of Sensitivity/Susceptibility in the Developing or Young Animal

HED determined that evidence of neither quantitative nor qualitative increased susceptibility of 

fetuses to in utero exposure to acetamiprid was observed in either developmental toxicity study 
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in rat or rabbit. However, in the 2-generation reproduction study, evidence of qualitative 

increased susceptibility of rat pups was observed. While parental and offspring NOAELs and 

LOAELs are set at the same doses, the effects in the offspring (including decreased viability) are 

considered to be more severe than those observed in the parents (decreased body weight and 

body weight gain). In the DNT study, maternal and offspring effects were observed at the same 

dose. However, the offspring effects included decreased pup viability, which is considered to be 

more severe than the maternal body weight effects. Therefore, HED concluded that there was 

evidence of increased qualitative susceptibility to fetuses exposed in utero and/or during 

lactation in the DNT study. No evidence of quantitative increased susceptibility was observed in 

any study. 

4.2.4 Residual Uncertainty in the Exposure Database

Since there is evidence of increased qualitative susceptibility of the young following in utero 

exposure to acetamiprid in the rat reproduction study, and increased qualitative susceptibility to 

pups in the DNT study, HED performed a degree of concern analysis to: 

1) Determine the LOC for the effects observed when considered in the context of 

all available toxicity data; and 

2) identify any residual uncertainties after establishing toxicity endpoints and 

traditional uncertainty factors to be used in the acetamiprid risk 

assessment. 

If residual uncertainties are identified, HED examines whether the residual uncertainties can be 

addressed by an FQPA SF, and if so, what factors should be retained. 

Considering the overall toxicity profile and the endpoints and doses selected for the acetamiprid 

risk assessment, HED characterized the degree of concern for the effects observed in the 

acetamiprid DNT study as low, noting that there is a clear NOAEL for the offspring effects, and 

regulatory doses were selected to be protective of these effects. No other residual uncertainties 

were identified with respect to susceptibility. HED believes that the endpoints and doses 

selected for acetamiprid are protective of adverse effects in both offspring and adults. 

HED has used conservative assumptions in the exposure assessment, including the use of 100% 

crop treated (% CT) assumptions, tolerance-level residue values, and upper-bound estimates of 

potential exposure through drinking water. In addition, the residential exposure assessment was 

conducted such that residential exposure and risk will not be underestimated. The aggregate 

exposure and risk estimates presented in this assessment are expected to over-estimate the actual 

exposure and risk anticipated, based on the current and proposed use patterns; no risk estimates 

of concern were identified. 
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4.3 Toxicity Endpoint and Point of Departure Selections

The toxicological endpoints and PODs selected for dietary and occupational exposure and risk 

assessment are presented in Tables 4.3.1 and 4.3.2 (below). The complete toxicological profile 

for acetamiprid is summarized in Appendix A.2. For this assessment, endpoints and PODs have 

been selected for long-term incidental oral and dermal exposure, since long term exposure is 

anticipated based on the proposed pet use. There have been no other changes to the 

endpoints/PODs selected for risk assessment or the cancer classification. 

For acute dietary and short- and intermediate-term incidental oral, dermal and inhalation 

exposure, the DNT NOAEL of 10 mg/kg/day was selected, with a LOAEL of 45 mg/kg/day. In 

this DNT study, parental effects were limited to decreased body weight and body weight gains, 

while the offspring effects noted were decreased body weights and body weight gains, decreased 

pre-weaning survival (PNDs 0-1), and decreased maximum auditory startle response in males on 

PNDs 20 and 60. 

For chronic dietary and long-term incidental oral and dermal exposure, the combined 

chronic/carcinogenicity rat NOAEL of 7.1 mg/kg/day was selected, with a LOAEL of 17.5 

mg/kg/day. In the study, decreased body weight and body weight gains were seen in females,

and hepatocellular vacuolation was observed in males. 

Since an oral study was selected for assessing risks associated with dermal and inhalation 

exposure, a dermal absorption factor of 10% was applied to dermal risk assessments, and toxicity 

via the inhalation route is considered to be equivalent to toxicity via the oral route. 

For all of the relevant routes and durations of exposure, clear NOAELs and LOAELs were 

identified. In addition, the toxicity database is considered to be largely complete, and no 

database uncertainty factors (UFs) were needed to account for missing data. With the reduction 

of the FQPA SF to 1X, the standard uncertainty factors of 100X (based on 10X for intraspecies 

variability, and 10X for interspecies extrapolation) were applied. For dermal and inhalation risk 

assessment, the LOC is a margin of exposure (MOE) of <100. For dietary assessments, the 

combined UF of 100X was incorporated into the relevant reference doses (RfDs) and population 

adjusted doses (PADs).
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TABLE 4.3.1 Summary of Toxicological Doses and Endpoints of Acetamiprid for Use in Dietary and 

Non-Occupational Human Health Risk Assessment.

Exposure 

Scenario

POD Used in 

Risk 

Assessment

Uncertainty 

Factors/FQPA

Safety Factors

PAD; LOC

for Risk 

Assessment

Study and Toxicological Effect

Acute Dietary (all 

populations)

NOAEL = 10 

mg/kg/day

UFA = 10X

UFH = 10X

FQPA SF = 1X

aPAD = 0.10 

mg/kg/day

Co-critical studies

Developmental Neurotoxicity in rat

LOAEL = 45 mg/kg/day, based on 

decreased early pup survival on PND 

0-1, and decreased startle response on 

PND 20/60 in males.

Acute Neurotoxicity Study in rat

LOAEL = 30 mg/kg/day, based on 

decreased locomotor activity

Chronic Dietary

(all populations)

NOAEL = 7.1 

mg/kg/day

UFA = 10X

UFH = 10X

FQPA SF = 1X

cPAD = 0.071 

mg/kg/day

Chronic Toxicity/Oncogenicity Study 

in rat

LOAEL = 17.5 mg/kg/day, based on 

decreased body weight and body 

weight gains in females, and 

hepatocellular vacuolation in males.

Short- and 

Intermediate-term 

Incidental Oral 

(1-30 days, 1-6 

months)

NOAEL = 10 

mg/kg/day

UFA = 10X

UFH = 10X

FQPA SF = 1X

Residential 

LOCfor MOE 

< 100

Developmental Neurotoxicity in rat

LOAEL = 45 mg/kg/day, based on 

decreased body weight and body 

weight gains in offspring, decreased 

early pup survival on PND 0-1, and 

decreased startle response on PND 

20/60 in males.

Long-term 

Incidental Oral 

(> 6 months)

NOAEL = 7.1 

mg/kg/day 

UFA = 10X

UFH = 10X

FQPA SF = 1X

Residential 

LOC for MOE 

= 100

Chronic Toxicity/Oncogenicity Study 

in rat

LOAEL = 17.5 mg/kg/day, based on 

decreased body weight and body 

weight gains in females, and 

hepatocellular vacuolation in males.

Short- and 

Intermediate-term 

Dermal

(1-30 days, 1-6 

months)

NOAEL = 10 

mg/kg/day

DAF = 10%

UFA = 10X

UFH = 10X

FQPA SF = 1X

Residential 

LOC for MOE 

< 100

Developmental Neurotoxicity in rat

LOAEL = 45 mg/kg/day, based on 

decreased body weight and body 

weight gains in offspring, decreased 

early pup survival on PND 0-1, and 

decreased startle response on PND 

20/60 in males.
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TABLE 4.3.1 Summary of Toxicological Doses and Endpoints of Acetamiprid for Use in Dietary and 

Non-Occupational Human Health Risk Assessment.

Exposure 

Scenario

POD Used in 

Risk 

Assessment

Uncertainty 

Factors/FQPA

Safety Factors

PAD; LOC

for Risk 

Assessment

Study and Toxicological Effect

Long-term Dermal 

(> 6 months)

NOAEL = 7.1 

mg/kg/day 

DAF = 10%

UFA = 10X

UFH = 10X

FQPA SF = 1X

Residential 

LOC for MOE 

< 100

Chronic Toxicity/Oncogenicity Study 

in rat

LOAEL = 17.5 mg/kg/day, based on 

decreased body weight and body 

weight gains in females, and 

hepatocellular vacuolation in males.

Short- and 

Intermediate-term 

Inhalation

(1-30 days, 1-6 

months)

NOAEL = 10 

mg/kg/day

Inhalation 

toxicity 

assumed to be 

equivalent to 

oral toxicity

UFA = 10X

UFH = 10X

FQPA SF = 1X

Residential 

LOC for MOE 

< 100

Developmental Neurotoxicity in rat

LOAEL = 45 mg/kg/day, based on 

decreased body weight and body 

weight gains in offspring, decreased 

early pup survival on PND 0-1, and 

decreased startle response on PND 

20/60 in males.

Cancer (oral, dermal, inhalation) = not likely to be carcinogenic to humans (2005 revised Agency cancer 

guidelines).

DAF = dermal absorption factor. Point of Departure (POD) = A data point or an estimated point that is derived from 

observed dose-response data and used to mark the beginning of extrapolation to determine risk associated with 

lower environmentally relevant human exposures. NOAEL = no observed adverse effect level. LOAEL = lowest 

observed adverse effect level. UF = uncertainty factor. UFA = extrapolation from animal to human (interspecies). 

UFH = potential variation in sensitivity among members of the human population (intraspecies). FQPA SF = FQPA 

Safety Factor. UFDB = Database uncertainty factor retained for missing data. PAD = population adjusted dose (a = 

acute, c = chronic) = reference dose/all uncertainty factors. MOE = margin of exposure. LOC = level of concern. 

TABLE 4.3.2 Summary of Toxicological Doses and Endpoints of Acetamiprid for Use in Occupational 

Human Health Risk Assessment.

Exposure Scenario POD Used in 

Risk Assessment

Uncertainty 

Factors

LOC for Risk 

Assessment

Study and Toxicological Effect

Short- and

Intermediate-term

Dermal 

(1-30 days, 1-6 months)

NOAEL = 10 

mg/kg/day

DAF = 10%

UFA = 10X

UFH = 10X

Occupational 

LOCfor MOE 

< 100

Developmental Neurotoxicity in rat

LOAEL = 45 mg/kg/day, based on 

decreased body weight and body 

weight gains in offspring, 

decreased early pup survival on 

PND 0-1, and decreased startle 

response on PND 20/60 in males.

Long-term Dermal 

(> 6 months)

NOAEL = 7.1 

mg/kg/day 

UFA = 10X

UFH = 10X

Occupational 

LOC for MOE 

< 100

Chronic Toxicity/Oncogenicity 

Study in rat

LOAEL = 17.5 mg/kg/day, based 

on decreased body weight and 

body weight gains in females, and 

hepatocellular vacuolation in 

males.
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Short- and 

Intermediate-term 

Inhalation 

(1-30 days, 1-6 months)

Note: Not applicable 

to the proposed pet 

use because inhalation 

exposure is negligible.

NOAEL = 10 

mg/kg/day

Inhalation 

toxicity assumed 

to be equivalent 

to oral toxicity

UFA = 10X

UFH = 10X

Occupational 

LOC for MOE 

< 100

Developmental Neurotoxicity in rat

LOAEL = 45 mg/kg/day, based on 

decreased body weight and body 

weight gains in offspring, 

decreased early pup survival on 

PND 0-1, and decreased startle 

response on PND 20/60 in males.

Cancer (oral, dermal, inhalation) = not likely to be carcinogenic to humans (2005 revised Agency cancer 

guidelines).

Point of Departure (POD) = A data point or an estimated point that is derived from observed dose-response data and 

used to mark the beginning of extrapolation to determine risk associated with lower environmentally relevant human 

exposures. NOAEL = no observed adverse effect level. LOAEL = lowest observed adverse effect level. UF = 

uncertainty factor. UFA = extrapolation from animal to human (interspecies). UFH = potential variation in 

sensitivity among members of the human population (intraspecies). DAF = dermal absorption factor. MOE = 

margin of exposure. LOC = level of concern. 

5.0 Dietary Exposure and Risk Assessment 

5.1 Metabolite/Degradate Residue Profile

The nature of the residue for acetamiprid has been adequately delineated, based on acceptable 

plant and livestock metabolism studies, as well as confined rotational crop studies. The parent 

compound is the only residue of concern in drinking water, based on environmental fate data. 

The residue definitions for tolerance enforcement and risk assessment are summarized in Table 

5.1 (below). For further details on these metabolism studies, please refer to the briefing

(D278352; M. Doherty et al; 16 October 2001) and decision (D278652; M. Doherty et al; 13 

November 2001) memoranda. 

TABLE 5.1 Summary of Acetamiprid Metabolites and Degradates to be included in the Risk 

Assessment and Tolerance Expression. 

Matrix Residues Included in Risk Assessment Residues Included in 

Tolerance Expression

Plants Primary Crop Acetamiprid Acetamiprid

Rotational Crop NA* None at this time

Livestock Ruminant Acetamiprid + IM-2-1 + IM-2-1-amide (muscle only) Acetamiprid + IM-2-1

Poultry Acetamiprid and IM-2-1 Acetamiprid + IM-2-1

Drinking Water Acetamiprid NA

* NA = Not Applicable. 

5.2 Food Residue Profile

Residue Chemistry Summary Document D423321; W.T. Drew; 2 September 2015

IR-4 submitted a petition (4E8307) requesting an amended use pattern (shorter PHI), and revised 

tolerances in clover forage and hay, for use of acetamiprid on clover grown for seed in ID, OR 

and WA only. The proposed PHI is 30 days for clover, compared to the currently registered PHI 

of 56 days. The petition was submitted along with field trial data for acetamiprid on clover 
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grown for seed in response to an Agency request for two additional clover field trials as 

confirmatory data (D364833; D. McNeilly; 14 October 2009). In conjunction with the petition, 

IR-4 has proposed the revision of established tolerances for residues of acetamiprid in or on 

clover forage (from 0.10 to 0.3 ppm) and clover hay (from 0.01 to 1.5 ppm), with regional 

registration (in ID, OR and WA only). The proposed tolerance in clover forage is supported 

adequately by the current submitted field trial residue data, in conjunction with previously 

submitted field trial data (D364833; D. McNeilly; 14 October 2009). The current submitted field 

trial residue data support the recommended tolerances in clover forage and in clover hay of 0.30 

and 2.0 ppm, respectively. 

Two pairs of field trials were conducted in the US in North American Free Trade Agreement 

(NAFTA) Growing Zone 11 during the 2010 (MRID #49443801) and 2012 (MRID #49443802) 

growing seasons. Applications were made in accordance with the proposed labeling, and the 

residue data are supported by appropriate analytical method and storage stability data. Table 

5.2.1 (below) summarizes the submitted field trial data for clover forage and hay. 

The OECD tolerance calculation procedure was used for setting tolerances in clover forage and 

in clover hay, using residue data from the submitted clover field trial studies. The submitted 

clover field trial data support a tolerance of 2.0 ppm, instead of the proposed tolerance of 1.5 

ppm, in clover hay. The petitioner used residues in clover hay from all field trials to calculate 

the tolerance (PHIs of 27-63 days). The draft labels stipulate a PHI of 30 days (decreased from 

56 days on the current labels). Therefore, only residues from those trials where hay was 

collected at PHIs of 27-32 days (current submitted data) were used to calculate the tolerance; 

residues from those trials where hay was collected at PHIs of 50-63 days (previously submitted 

data) were not used. HED utilized the residue data for hay collected at PHIs of 27-32 as the 

input dataset for the OECD tolerance calculation procedure, yielding a different result (2.0 ppm). 

The proposed tolerance increase in clover forage (from 0.10 to 0.30 ppm) is supported 

adequately by the current submitted field trial residue data, in conjunction with previously 

submitted field trial data (D364833; D. McNeilly; 14 October 2009). The current submitted field 

trial residue data support the recommended tolerance increase in clover hay (from 0.01 to 2.0 

ppm). 

TABLE 5.2.1 Summary of Residue Data from Clover Field Trials with Acetamiprid.

Crop Matrix Total Use 

Rate (lb ai/A)

PHI 

(Days)

n

1 Residues (ppm)

Min.2 Max.2 LAFT3 HAFT3 Median3 Mean3 SD3

Clover forage 0.075-0.080 27-32 3 0.0496 0.169 0.0812 0.163 0.102 0.115 0.0425

Clover hay 0.075-0.080 27-32 3 0.200 0.763 0.450 0.753 0.462 0.555 0.172

0.077-0.080 50-53 2 0.0592 0.116 0.0648 0.111 0.0879 0.0879 NA4

1. n = number of field trials. 

2. Values based on individual samples. 

3. Values based on per-trial averages. LAFT = Lowest Average Field Trial; HAFT = Highest Average Field Trial; 

SD = Standard Deviation. 

4. NA = Not Applicable (standard deviation is not calculated for sample sets where n < 3). 
Acetamiprid Human Health Risk Assessment D423298, D426115, D426117, D427194

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5.3 Water Residue Profile

Drinking Water Assessment D423299; K. White; 25 March 2015

In a drinking water assessment memo (D423299; K. White; 25 March 2015), the Environmental 

Fate and Effects Division (EFED) provided estimated residues of acetamiprid in surface and 

groundwater sources of drinking water from the use of acetamiprid on cranberries, and as a 

scatter bait. The scatter bait use results in the highest estimated drinking water concentrations 

(EDWCs) for chronic scenarios, while the use on cranberry results in the highest EDWCs for 

acute scenarios. The EDWCs used in the dietary exposure and risk assessment are summarized 

(bold-face type) in Table 5.3, below. The surface water EDWCs were generated using the Food 

Quality Protection Act Index Reservoir Screening Tool (FIRST) Model, and the groundwater 

EDWCs are from the Pesticide Root Zone Model for GroundWater (PRZM-GW) Model. The 

models and their descriptions are available at the EPA internet site 

http://www.epa.gov/oppefed1/models/water/. 

TABLE 5.3 EDWCs for Acetamiprid.*

Source of Drinking 

Water [Model]

EDWCs (ppm), scatter bait, 0.082 lbs 

ai/A, 24X, 3-day RTI, ground.

EDWCs (ppm), cranberries,

0.13 lbs ai/A, 2X, 7-day RTI, aerial.

Surface water [FIRST] Acute = 0.0815 Acute = 0.0883 

Groundwater [PRZM-GW] Post-breakthrough average = 0.045 

(Daily peak = 0.0497)

--

* The highest EDWCs for the proposed and previously evaluated use scenarios are in bold-face type. 

For the acute assessment, an EDWC of 0.0883 ppm was entered into the DEEM-FCID Model for 

“water, direct, all sources” and “water, indirect, all sources.” For the chronic assessment, the 

value of 0.045 ppm was used for the same inputs. 

No monitoring data are currently available to further characterize potential drinking water 

exposure. In the dietary exposure and risk assessment conducted to support the proposed use

pattern and label changes, HED incorporated the highest EDWCs directly into the acute and 

chronic dietary models. The use of the highest EDWCs in the dietary assessment is therefore 

protective of potential exposure through surface and groundwater sources of drinking water. 

5.4 Dietary Risk Assessment

Dietary Exposure and Risk Assessment D427703; W.T. Drew; 2 September 2015

Acute and chronic aggregate dietary (food and drinking water) exposure and risk assessments 

were conducted using the Dietary Exposure Evaluation Model software with the Food 

Commodity Intake Database (DEEM-FCID), Version 3.16. This software uses 2003-2008 food 

consumption data from the US Department of Agriculture’s (USDA’s) National Health and 

Nutrition Examination Survey, What We Eat in America (NHANES/WWEIA). Per HED policy, 

residue estimates associated with the food-handling establishment use are not included in the 

acute dietary assessment. 

Both the acute and chronic analyses are based on tolerance-level residues and assume 100% CT. 

Acute and chronic dietary risk estimates are below HED’s LOC for all population subgroups (see 
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Table 5.4, below). For acute exposures, the dietary risk for the US population is estimated to be 

25% of the PAD. Acute risk for children 1-2 years old, the highest-exposed population 

subgroup, is estimated to be 67% of the PAD. Chronic risk estimates are 14% of the PAD for 

the US population, and 61% of the PAD for children 1-2 years old. Acetamiprid is classified as 

“not likely to be carcinogenic to humans,” and therefore cancer risk is not of concern for this 

chemical. 

There are no dietary exposure or risk concerns that would preclude granting the requested use of 

acetamiprid on clover with a shorter PHI, and establishing increased tolerances in clover forage 

and hay associated with the revised use pattern. Furthermore, based on the conservative 

assumptions used in the dietary exposure assessment, actual dietary exposure is expected to be 

much lower than the estimates provided in the table.

TABLE 5.4 Summary of Dietary Exposure and Risk Estimates for Acetamiprid. 

Population Subgroup* Acute (95th Percentile) Chronic

Exposure (mg/kg/day) % aPAD Exposure (mg/kg/day) % cPAD

US Population (total) 0.024712 25 0.009989 14

All infants (<1 year) 0.050938 51 0.018612 26

Children 1-2 years 0.067393 67 0.043166 61

Children 3-5 years 0.045688 46 0.028154 40

Children 6-12 years 0.026021 26 0.013964 20

Youth 13-19 years 0.015309 15 0.007674 11

Adults 20-49 years 0.015682 16 0.007101 10

Adults 50-99 years 0.015579 16 0.007532 11

Females 13-49 years 0.015939 16 0.007299 10

* Populations with the highest exposure estimates are bolded. 

6.0 Residential (Non-Occupational) Exposure/Risk Characterization

Occupational and Residential Exposure Assessment D427194; J. Godshall; 19 August 2015

This residential exposure/risk assessment was conducted in support of the proposed new use of 

acetamiprid in a spot-on product for dogs. Acetamiprid is a neonicitinoid insecticide chemical 

currently registered for use in controlling a wide variety of indoor and outdoor insect pests in 

residential settings. Currently registered residential sites include various insecticide traps, spoton pet treatment, crack and crevice treatments, soil treatments, and sprays. 

The proposed new EP, RF2213 AE CDSO Insecticide, is formulated as a pet spot-on treatment 

containing 9.5% acetamiprid combined with other pesticides (20.0% etofenprox, 8.0% piperonyl 

butoxide, and 5.0% s-methoprene) to broaden the efficacy spectrum. This assessment addresses 

exposure and risk associated with the use of acetamiprid only; it does not address etofenprox, 

piperonyl butoxide, or s-methoprene exposure associated with the use of the spot-on product. 

The new EP is proposed by Nippon Soda for use as a monthly topical spot-on product for dogs to 

provide continuous protection against fleas, ticks and mosquitoes. RF2213 AE CDSO is 
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proposed for use by homeowners and commercial applicators. The proposed spot-on product 

label allows for application to four dog weight ranges: small, 4 to 9 lbs; medium, 10 to 22 lbs; 

large, 23 to 55 lbs; and extra-large, ≥56 lbs. The product is not proposed for use on cats. 

Non-occupational (residential) use of the proposed dog spot-on product is anticipated to result in 

dermal exposures for adult handlers. In addition, residential post-application dermal exposures 

are expected for adults and children 1 to 2 years old, and incidental oral exposures for children 1 

to 2 years old. Inhalation exposure from the use of the spot-on product is considered negligible. 

Therefore, only dermal and incidental oral exposure were assessed for the proposed product. 

Current HED policy requires assessment for residential post-application exposures associated 

with short- (1 to 30 days), intermediate- (1 to 6 months), and long-term (greater than 6 months) 

durations from pet spot-on products due to the preventative nature of pet products, and the 

potential for extended usage in more temperate parts of the country. 

Short-term

Residential handler exposure is assumed to be short-term due to the intermittent nature of 

homeowner spot-on applications (once-monthly treatment). A summary of residential handler 

exposure risk estimates is presented in Table 6.0.1 (below). 

TABLE 6.0.1 Residential Handler Short-Term Non-cancer Exposure and Risk Estimates from the 

Proposed Spot-On Pet Use.

Exposure 

Scenario

Dermal Unit 

Exposure 

(mg/lb ai)

Maximum Use Rate1

(lb ai/pet)

Amount 

Treated 

Daily2

Dermal

Dose 

(mg/kg/day)3

MOE4

Spot-on

treatment

(9.5% ai)

120 0.00018 (small) 2 Dogs 0.000063 160,000

0.00045 (medium) 0.00016 64,000

0.0011 (large) 0.00038 26,000

0.0018 (extra-large) 0.00063 16,000

1. Based on the proposed label (EPA File Symbol 8033-RGR). [(fl oz product) × (0.84455 lb ai/gal) ÷ (128 fl 

oz/gal)]. 

2. Based on HED’s 2012 Residential SOPs for Treated Pets (http://www.epa.gov/pesticides/science/residentialexposure-sop.html). 

3. Dermal dose = dermal unit exposure (mg/lb ai) × application rate (lb ai/treatment) × amount treated (2 dogs/day) 

× dermal absorption factor (0.1) ÷ body weight (69 kg). 

4. Dermal MOE = dermal NOAEL (10 mg/kg/day) ÷ dermal dose (mg/kg/day). Inhalation exposure is expected to 

be negligible. 

Conclusion: Residential handler short-term dermal risk estimates are not of concern (MOEs are 

all ≥100) for application to all dog weight ranges proposed. 

Short-, Intermediate- and Long-Term

HED combines risk values resulting from separate routes of exposure when it is likely they can 

occur simultaneously based on the use pattern and the behavior associated with the exposed 
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population, and if the hazard associated with the PODs is similar across routes. Residential postapplication inhalation exposure is expected to be negligible from the proposed spot-on product;

therefore, a quantitative assessment was not performed. 

Post-application dermal and incidental oral exposures were combined for children 1 to 2 years 

old. Children’s combined exposures (all durations) are presented as total MOEs. For adults, 

only post-application dermal exposure is anticipated from contact with a treated dog. 

Residential short- and intermediate-term post-application exposures are presented in Table 6.0.2

(below). 

TABLE 6.0.2 Residential Short- and Intermediate-Term Post-Application Non-Cancer Exposure and 

Risk Estimates from the Proposed Spot-On Pet Use.

Lifestage Post-application Exposure 

Scenario

Application Rate

(mg ai)1

Dose 

(mg/kg/day)2

Short-/IntTerm

MOEs3

Total 

MOE4

Use Site Exposure Route

Adult Dog Spot -

On

Dermal 80 (small) 0.006 1,700 NA

203.5 (medium) 0.008 1,200

505.8 (large) 0.012 860

811 (extra-large) 0.010 950

Children

1 to 2

Years Old

Dermal 80 (small) 0.013 790 720

Incidental Oral 0.0013 7,900

Dermal 203.5 (medium) 0.018 570 510

Incidental Oral 0.0018 5,700

Dermal 505.8 (large) 0.026 390 360

Incidental Oral 0.0026 3,900

Dermal 811 (extra-large) 0.023 440 400

Incidental Oral 0.0023 4,300

1. Based on the proposed label (EPA File Symbol 8033-RGR). 

2a. Dermal dose (mg/kg/day) = [(transfer coefficient (cm2/hr) × (application rate (mg ai) × fraction application rate 

(0.02) ÷ surface area of dog (cm2)) × exposure time (hours/day) × absorption factor (unitless)) ÷ body 

weight (kg)]. 

2b. Hand-to-mouth dose (mg/kg/day) = [(hand residue loading (mg/cm2) × fraction of hand mouthed (0.13) × 

surface area of 1 hand (150 cm2) × exposure time (1.5 hrs/day) × # of replenishment intervals/hour (4 

int/hr) × (1-((1-saliva extraction factor (0.5))^(number of hand-to-mouth events/hour (13.9 events/hr)) ÷ (# 

of replenishment intervals/hour))] ÷ body weight (kg)]. 

3. Short- and intermediate-term MOE = dermal or incidental oral POD (mg/kg/day) ÷ dose (mg/kg/day). 

4. Short- and intermediate-term total MOE = 1/ [(1/dermal MOE) + (1/incidental oral MOE)]. 

Residential long-term post-application exposures are presented in Table 6.0.3 (below). 
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TABLE 6.0.3 Residential Long-Term Post-Application Non-Cancer Exposure and Risk Estimates from 

the Proposed Spot-On Pet Use.

Lifestage Post-application Exposure 

Scenario

Application Rate

(mg ai)1

Dose (mg/kg/day)2 Route 

Specific 

MOEs3

Total MOE4

Use Site Exposure Route

Adult Dog SpotOnDermal 80 (small) 0.0050 1,400 NA

203.5 (medium) 0.0070 1,000

505.8 (large) 0.010 710

811 (extra-large) 0.0090 790

Children

1 to 2 Years 

Old

Dermal 80 (small) 0.013 560 510

Incidental Oral 0.0013 5,600

Dermal 203.5 (medium) 0.018 400 370

Incidental Oral 0.0018 4,000

Dermal 505.8 (large) 0.026 280 250

Incidental Oral 0.0026 2,800

Dermal 811 (extra-large) 0.023 310 280

Incidental Oral 0.0023 3,100

1. Based on the proposed label (EPA File Symbol 8033-RGR). 

2a. Dermal dose (mg/kg/day) = [(transfer coefficient (cm2/hr) × (application rate (mg ai) × fraction application rate 

(0.02) ÷ surface area of dog (cm2)) × exposure time (hours/day) × absorption factor (unitless)) ÷ body 

weight (kg)]. 

2b. Hand-to-mouth dose (mg/kg/day) = [(hand residue loading (mg/cm2) × fraction of hand mouthed (0.13) × 

surface area of 1 hand (150 cm2) × exposure time (1.5 hrs/day) × # of replenishment intervals/hour (4 

int/hr) × (1-((1-saliva extraction factor (0.5))^(number of hand-to-mouth events/hour (13.9 events/hr)) ÷ (# 

of replenishment intervals/hour))] ÷ body weight (kg)]. 

3. Short- and intermediate-term MOE = dermal or incidental oral POD (mg/kg/day) ÷ dose (mg/kg/day). 

4. Short- and intermediate-term total MOE = 1/ [(1/dermal MOE) + (1/incidental oral MOE)]. 

Conclusion: Residential post-application exposure and risk estimates are not of concern for any 

sized dog (adult dermal MOEs are all ≥100, and children 1 to 2 years old total MOEs are all 

≥100) for all exposure durations. 

Residential Risk Estimates for Use in Aggregate Assessments

Table 6.0.4 presents the residential risk estimates recommended for use in the aggregate 

assessment for acetamiprid. The short- and intermediate-term endpoints were derived from a 

previous assessment (D383325; M. Collantes; 22 July 2011), and are listed in the table. Please 

note the following considerations: 

1) The recommended residential exposure for use in the adult aggregate shortintermediate term assessment reflects dermal and inhalation exposure 

from applications to mattresses, cracks and crevices; 

2) the recommended residential exposure for use in the children 1 to 2 years old 

short- and intermediate-term aggregate assessment reflects dermal, 

inhalation and hand-to-mouth exposures from post-application exposure to 

indoor applications; 
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3) the recommended residential exposure for use in the adult aggregate long term

assessment reflects post-application dermal exposures from contact with 

spot-on treated pets; and

4) the recommended residential exposure for use in the children 1 to 2 years old 

long term aggregate assessment reflects post-application dermal and handto-mouth exposures from contact with spot-on treated pets. 

TABLE 6.0.4 Recommended Residential Exposures for Use in Acetamiprid Aggregate Assessments.

Lifestage Exposure Scenario Dose (mg/kg/day)1 MOE2

Dermal Inhalation Oral Total Dermal Inhalation Oral Total

Short- and Intermediate-Term3

Adult 

Male/Female

Handler Mattress Treatment 0.00088 0.000039 NA4

0.00092 11,000 260,000 NA 3,600

Handler Crack & Crevice 0.0018 0.000078 NA 0.0019 5,600 130,000 NA

Post-app Mattress Treatment 0.00015 NA NA 0.00015 66,000 NA NA 430

Post-app Crack & Crevice 0.023 0.000018 NA 0.023 430 560,000 NA

Child Post-app Mattress Treatment 0.00032 NA NA 0.00032 900 NA NA 220

Post-app Crack & Crevice 0.033 0.000046 NA 0.033 300 220,000 NA

Post-app Hand-to-Mouth NA NA 0.011 0.011 NA NA 900

Long-Term5

Adult 

Male/Female

Post-app Pet Spot-on 0.010 NA NA 0.010 710 NA NA 710

Child Post-app Pet Spot-on 0.026 NA 0.0026 0.029 280 NA 2,800 250

1. Dose = the highest dose for each applicable lifestage of all residential scenarios assessed. Total = dermal + 

inhalation + incidental oral (where applicable). 

2. MOE = the MOEs associated with the highest residential doses. Total = 1 ÷ (1/dermal MOE) + (1/inhalation 

MOE) + (1/Incidental Oral MOE), where applicable. 

3. Values taken from D383325; M. Collantes; 22 July 2011. 

4. NA = Not Applicable. 

5. Values taken from Table 6.0.3 (above).

6.1 Spray Drift

Due to the application technique and product formulation, spray drift is not considered to be a 

concern for the pet spot-on use. 

Spray drift is always a potential source of exposure to residents nearby to spraying operations. 

This is particularly the case with aerial applications allowed on acetamiprid labels but, to a lesser 

extent, could also be a potential source of exposure from ground application methods employed 

for acetamiprid. The Agency has been working with the Spray Drift Task Force, EPA Regional 

Offices, State Lead Agencies for pesticide regulation, and other parties to develop the best spray 

drift management practices (see the Agency’s Spray Drift website for more information at 

http://www.epa.gov/opp00001/factsheets/spraydrift.htm). On a chemical-by-chemical basis, the 

Agency is now requiring interim mitigation measures for aerial applications that must be placed 

on product labels/labeling. The Agency has completed its evaluation of the new database 
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submitted by the Spray Drift Task Force, a membership of US pesticide registrants, and is 

developing a policy on how to appropriately apply the data and the AgDRIFT computer model to 

its risk assessments for pesticides applied by air, orchard airblast and ground hydraulic methods. 

After the policy is in place, the Agency may impose further refinements in spray drift 

management practices to reduce off-target drift of specific products having significant risks 

associated with drift. 

Although a quantitative residential post-application inhalation exposure assessment was not 

performed as a result of pesticide drift from neighboring treated agricultural fields, an inhalation 

exposure assessment was performed for flaggers. This exposure scenario is representative of a 

worse case inhalation (drift) exposure, and may be considered protective of most outdoor 

agricultural and commercial post-application inhalation exposure scenarios. 

7.0 Aggregate Exposure/Risk Characterization

In accordance with the FQPA, HED must consider and aggregate (add) pesticide risks from three 

major sources (food, drinking water, and residential exposures). When aggregating exposures 

and risks from various sources, HED considers toxicological endpoints, as well as the route and 

duration of exposure. 

7.1 Acute Aggregate Risk

Typically, HED does not consider residential exposures when assessing acute aggregate risk

unless such exposures can be characterized as a series of single-day exposures. For acetamiprid, 

residential exposures are assessed as short- and intermediate-term exposures. Therefore, acute 

aggregate risk estimates for acetamiprid are equivalent to the acute dietary risk estimates (see 

Section 5.4) and are below HED’s LOC. 

7.2 Short- and Intermediate-Term Aggregate Risk

Toxicological endpoints and points of departure for assessing short- (1 to 30 days) and 

intermediate-term (1 to 6 months) risks associated with exposure to acetamiprid are identical. 

Therefore, separate assessments are not being conducted for these durations. Short- and 

intermediate-term residential exposures to acetamiprid may occur from uses of this chemical 

around the home (Section 6.0). The proposed spot-on use of acetamiprid results in a lower 

exposure estimate than the currently registered crack/crevice use, which serves as the basis for 

calculating aggregate risk. In addition, dietary exposure is possible from acetamiprid residues in 

food and drinking water (Section 5.4). For assessing aggregate risk, the chronic dietary exposure 

estimate is used, since it represents a background exposure level from food and drinking water 

that may co-occur with residential exposures. The toxicological endpoints, PODs, and LOC are 

the same across oral, dermal, and inhalation routes of exposure for acetamiprid. Therefore, 

aggregate risk can be estimated by combining the various exposure estimates, and comparing the 
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resulting aggregate exposure estimate (see Table 7.2, below) to the short- and intermediate-term 

POD. 

TABLE 7.2 Short- and Intermediate-Term Aggregate Risk Estimates for Acetamiprid.

Population NOAEL 

mg/kg/day

LOC1 Average Food and Water 

Exposure mg/kg/day2

Residential 

Exposure 

mg/kg/day3

Aggregate 

Exposure 

mg/kg/day4

Aggregate 

MOE5

Short- and Intermediate-Term

Adult 10 100 0.007532 0.02597 0.033502 300

Child 10 100 0.043166 0.04432 0.087486 110

1. The LOC is based on the standard inter- and intra-species uncertainty factors totaling 100.

2. Dietary exposures are from Section 5.4 (above). Adult = 50-99 years old group (maximum exposure). Child = 

children 1-2 years. 

3. Combined residential exposure estimate from Section 6.0, above (specifically, from Table 6.0.4). 

4. Aggregate exposure = average food and water exposure + residential exposure. 

5. Aggregate MOE = NOAEL ÷ aggregate exposure. Values are rounded to two significant figures. 

Conclusions: Both short- and intermediate-term aggregate MOEs are ≥100, and indicate that 

risks are not of concern. The chronic dietary exposure estimates are highly conservative, 

assuming tolerance-level residues and 100% CT for all commodities. Therefore, HED also 

considers the aggregate MOEs to be conservative estimates, with the actual exposures likely 

being much lower than those characterized here. 

7.3 Chronic Aggregate Risk

Long-term residential exposures to acetamiprid may occur from uses of this chemical as a pet 

spot-on treatment (Section 6.0), which drives the aggregate risk, as the crack/crevice use does 

not have long term exposure. In addition, dietary exposure is possible from acetamiprid residues 

in food and drinking water (Section 5.4). The chronic dietary exposure and post-application pet 

spot-on residential exposure were aggregated and compared to the long-term POD (see Table 

7.3, below). 

TABLE 7.3 Long-Term Aggregate Risk Estimates for Acetamiprid.

Population NOAEL 

mg/kg/day

LOC1 Average Food and Water 

Exposure mg/kg/day2

Residential 

Exposure 

mg/kg/day3

Aggregate 

Exposure 

mg/kg/day4

Aggregate 

MOE5

Long-Term

Adult 7.1 100 0.007532 0.010 0.017532 570

Child 7.1 100 0.043166 0.029 0.072166 100

1. The LOC is based on the standard inter- and intra-species uncertainty factors totaling 100.

2. Dietary exposures are from Section 5.4 (above). Adult = 50-99 years old group (maximum exposure). Child = 

children 1-2 years. 

3. Combined residential exposure estimate from Section 6.0, above (specifically, from Table 6.0.4). 

4. Aggregate exposure = average food and water exposure + residential exposure. 

5. Aggregate MOE = NOAEL ÷ aggregate exposure. Values are rounded to two significant figures. 
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Conclusions: Both long-term aggregate MOEs are ≥100, and indicate that risks are not of 

concern. The chronic dietary exposure estimates are highly conservative, assuming tolerancelevel residues and 100% CT for all commodities. Therefore, HED also considers the aggregate 

MOEs to be conservative estimates, with the actual exposures likely being much lower than 

those characterized here. 

7.4 Cancer Aggregate Risk

Acetamiprid has been classified as “not likely to be carcinogenic to human” and, therefore, 

cancer risk is not of concern for this chemical. 

8.0 Cumulative Exposure/Risk Characterization

Unlike other pesticides for which EPA has followed a cumulative risk approach based on a 

common mechanism of toxicity, EPA has not made a common mechanism of toxicity finding as 

to acetamiprid and any other substance, and acetamiprid does not appear to produce a toxic 

metabolite produced by other substances. For the purposes of this tolerance action, therefore, 

EPA has not assumed that acetamiprid has a common mechanism of toxicity with other 

substances. For information regarding EPA’s efforts to determine which chemicals have a 

common mechanism of toxicity, and to evaluate the cumulative effects of such chemicals, see the 

policy statements released by EPA’s OPP concerning common mechanism determinations, and 

procedures for cumulating effects from substances found to have a common mechanism, on 

EPA’s website at http://www.epa.gov/pesticides/cumulative/.

9.0 Occupational Exposure/Risk Characterization

Occupational and Residential Exposure Assessment D427194; J. Godshall; 19 August 2015

This occupational exposure/risk assessment was conducted in support of the proposed new use of 

acetamiprid in a spot-on product for dogs, along with the proposed amendments to the label 

application rates of Assail 30 SG Insecticide and Assail 70 WP Insecticide. Acetamiprid is a 

neonicitinoid insecticide chemical currently registered for use on a number of agricultural, 

ornamental and residential sites. It is also used for seed treatment on canola, mustard and 

potatoes. 

Occupational handler exposures are anticipated from the application of the proposed acetamiprid 

spot-on product and augmented agricultural use labels. Occupational post-application exposure 

is anticipated from both the pet spot-on and agricultural uses. However, only a quantitative 

assessment has been conducted for the agricultural uses since occupational exposures are 

expected to be significantly less than residential post-application exposures from the spot-on 

product. 
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Proposed New Use

The proposed new EP, RF2213 AE CDSO Insecticide, is formulated as a pet spot-on treatment 

containing 9.5% acetamiprid combined with other pesticides (20.0% etofenprox, 8.0% piperonyl 

butoxide, and 5.0% s-methoprene) to broaden the efficacy spectrum. This assessment addresses 

exposure and risk associated with the use of acetamiprid only; it does not address etofenprox, 

piperonyl butoxide, or s-methoprene exposure associated with the use of the spot-on product. 

The new EP is proposed by Nippon Soda for use as a monthly topical spot-on product for dogs to 

provide continuous protection against fleas, ticks and mosquitoes. RF2213 AE CDSO is 

proposed for use by homeowners and commercial applicators. The proposed spot-on product 

label allows for application to four dog weight ranges: small, 4 to 9 lbs; medium, 10 to 22 lbs; 

large, 23 to 55 lbs; and extra-large, ≥ 56 lbs. The product is not proposed for use on cats. 

Proposed Amended Uses

The Assail 30 SG Insecticide and Assail 70 WP Insecticide products are formulated for broadcast 

agricultural use; both are for use by commercial applicators only. The amended labels propose 

increasing the maximum single application rates for cotton and leafy vegetables, while 

decreasing the number of applications per year. This does not result in an increase of the yearly 

application rate for either use. The amended label also includes new directions for application to 

fruiting vegetables crop group 8-10 to treat leafhoppers, but the application rates are no greater 

than currently exist for this crop group which has been previously assessed with no risks of 

concern identified (D394322; E. Holman; 19 April 2012). Therefore, a new assessment has not 

been included for fruiting vegetables crop group 8-10. The amended labels also included 

updated directions for use on leafy brassica, grapes, cucurbits, edible podded legume vegetables, 

succulent shelled peas and beans, and bush and cane berries. However, the changes will not 

impact worker risk/exposure, and were not assessed in this document. Required PPE for Assail 

30 SG and Assail 70 WP include long sleeved shirts, long pants, shoes plus socks, chemical 

resistant gloves, and chemical resistant headgear for overhead exposure. In addition, for aerial 

applications, Assail 70WP requires mixers/loaders to wear a dust mist filtering respirator. Both 

labels incorporate a 12 hour REI. 

9.1 Short-, Intermediate- and Long-Term Handler Risk

Proposed New Use

Based on the anticipated use patterns and current labeling, types of equipment and techniques 

that can potentially be used, occupational handler exposure could be expected from the 

acetamiprid spot-on use for veterinarians, veterinary assistants, and groomers. The quantitative 

exposure/risk assessment developed for occupational handlers (adults) is based on dermal 

exposure from the application of the spot-on product to dogs. Inhalation exposures are expected 

to be negligible from application of the spot-on product. 

For acetamiprid, occupational handler exposures from the pet spot-on use are expected to extend 

beyond a short- or intermediate-term duration due to temperate climates in some parts of the 

country, and the preventative nature of spot-on pet products. For these reasons, it is expected 

that veterinarians, veterinary assistants, and groomers could treat dogs with the proposed 
Acetamiprid Human Health Risk Assessment D423298, D426115, D426117, D427194

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acetamiprid spot-on product for all durations of exposure (short-, intermediate- and long-term) 

for flea and tick prevention and/or treatment. Agricultural use handlers are expected to 

experience short- and intermediate-term exposures. 

Conclusions: Occupational handlers of the proposed acetamiprid spot-on product could treat as 

many as 200 dogs per day (based on the long-term POD, which is protective of short- and 

intermediate-term exposure) without resulting in dermal risks of concern (all MOEs are ≥100). 

It is highly unlikely that this large a number of dogs could be treated daily in an occupational 

setting. Therefore, no risk concerns are anticipated from occupational use of the proposed dog 

spot-on product. A summary of occupational handler dermal risk estimates for this use is 

presented in Table 9.1.1 (below). 

TABLE 9.1.1 Occupational Handlers Long-Term1 Non-Cancer Exposure and Risk Estimates for Spot-on Pet Use.

Exposure 

Scenario

Target Dermal Unit 

Exposure

(mg/lb ai)2

Inhalation Unit 

Exposure

(mg/lb ai)2

Max.

Use Rate

(lb ai/pet)3

Max. 

Amount 

Handled 

Daily 

(Pets)4

Dermal Inhalation

Single Layer, No 

Gloves

No Respirator Dose 

(mg/kg/day)5

MOE6 Dose 

(mg/kg/day)

MOE

Applying 

spot-on 

product

Dogs 112 Negligible 0.00018 

(small)

200

Dogs

0.0058 1,200 Negligible

0.00045

(medium)

0.015 490

0.0011

(large)

0.036 200

0.0018

(extralarge)

0.058 120

1. The long-term risk estimates are protective of short- and intermediate-term exposure.

2. Based on the Occupational Pesticide Handler Unit Exposure Surrogate Reference Table (March 2012). Level of 

mitigation = baseline.

3. Based on proposed label (EPA File Symbol 8033-RGR).

4. High-end estimate of the number of dogs that could be treated per day. 

5. Dermal dose = dermal unit exposure (120 mg/lb ai) × application rate (lb ai/ treatment) × amount handled daily 

(treatments/day) × DAF (0.1) ÷ BW (69 kg).

6. Dermal MOE = long-term dermal NOAEL (7.1 mg/kg/day) ÷ dermal dose (mg/kg/day). 

Proposed Amended Uses

Occupational exposure could also be expected from the amended agricultural uses on cotton and 

leafy vegetables. 

Based on the anticipated use patterns and current labeling, types of equipment and techniques 

that can potentially be used, occupational handler exposure is expected from the proposed uses. 

The quantitative exposure/risk assessment developed for occupational handlers is based on the 

following scenarios: 

 Applying spot-on product to dogs.

 Mixing/loading WP for groundboom applications.

 Mixing/loading SG/WP for groundboom applications.
Acetamiprid Human Health Risk Assessment D423298, D426115, D426117, D427194

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 Mixing/loading WP for aerial applications.

 Mixing/loading SG/WP for aerial applications.

 Applying spray by groundboom equipment.

 Applying spray by aerial equipment.

 Flagging for spray by aerial equipment.

HED classifies exposures from 1 to 30 days as short-term, and exposures 30 days to six months 

as intermediate-term. Exposure duration is determined by many things, including the exposed 

population, the use site, the pest pressure triggering the use of the pesticide, and the cultural 

practices surrounding that use site. For most agricultural uses, it is reasonable to believe that 

occupational handlers will not apply the same chemical every day for more than a one-month 

time frame. However, there may be a large agribusiness and/or commercial applicators who may 

apply a product over a period of weeks (such as, completing multiple applications for multiple 

clients within a region). 

Conclusions: There are no risk estimates of concern for occupational handlers who mix, load

and/or apply acetamiprid (as the SG and WP formulations) to cotton and leafy vegetables when 

following the PPE directions for the amended uses (all MOEs are ≥100). A summary of 

occupational handler dermal risk estimates for these uses is presented in Table 9.1.2 (below). 
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TABLE 9.1.2 Occupational Handler Short- and Intermediate-term Non-Cancer Exposure and Risk Estimates for Agricultural 

Uses.

Exposure 

Scenario1

Crop or 

Target

Mitigation 

Level 2

Single

Use Rate

(lb ai/A)

Acres 

Treated

Dermal Inhalation Total

Dose 

(mg/kg/day)3

MOE Dose 

(mg/kg/day)4

MOE MOE5

Mixer/Loader

SG/WP for 

aerial 

application

Leafy 

Vegetables

SL/no G 0.1 350 0.012 870 0.0046 620 620

SL/G 0.0026 3,800 1400

SL/G

PF5 R

0.00091 11,000 2800

SG/WP for 

aerial 

application

Cotton SL/no G 0.15 1200 0.059 170 0.023 120 120

SL/G 0.014 740 270

SL/G

PF5 R

0.0047 2,100 550

SG/WP 

groundboom.

Leafy 

Vegetables

SL/no G 0.1 80 0.0026 3,800 0.0010 9,600 2700

SL/G 0.00060 17,000 6100

SL/G

PF5 R

0.00021 48,000 13000

SG/WP 

groundboom.

Cotton SL/no G 0.15 200 0.0099 1,000 0.0039 2,600 720

SL/G 0.0023 4,400 1600

SL/G

PF5 R

0.00078 13,000 3300

WP for aerial 

application

Leafy 

Vegetables

SL/no G 0.1 350 0.19 53 0.022 460 48

SL/G 0.0086 1,200 330

SL/G

PF5 R

0.0044 2,300 790

WP for aerial 

application

Cotton SL/no G 0.15 1,200 0.97 10 0.11 89 9

SL/G 0.044 230 64

SL/G

PF5 R

0.023 440 150

WP 

groundboom

Leafy 

Vegetables

SL/no G 0.1 80 0.043 230 0.0050 2,000 210

SL/G 0.0020 5,100 1400

SL/G

PF5 R

0.00010 10,000 3400

WP 

groundboom

Cotton SL/no G 0.15 200 0.16 62 0.019 530 56

SL/G 0.0074 1,400 380

SL/G

PF5 R

0.0037 2,700 920

Applicator

Spray with fixed 

wing aircraft

Leafy 

Vegetables

EC 0.1 350 0.00011 94,000 0.0000025 4,000,0

00

92,000

Cotton 0.15 1,200 0.00054 18,000 0.000013 780,000 18,000

Spray with 

groundboom

Leafy

Vegetables

SL/G 0.1 80 0.00019 53,000 0.000039 250,000 44,000

Cotton 0.15 200 0.00070 14,000 0.00015 68,000 12,000
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Abbreviations used: SL = Single Layer baseline personal protective equipment (PPE, also see # 3 below), SG = 

Soluble Granule, EC = Engineering Controls, G = chemical resistant Gloves, LOC= Level Of Concern, 

MOE = Margin Of Exposure, PF5 R = Protection Factor 5 Respirator, WP = Wettable Powder.

1. The use pattern is the same for all crops.

2. Baseline PPE includes long-sleeved shirt, long pants, and shoes with socks. Label recommended PPE is baseline 

plus chemical resistant gloves. Aerial applications using Assail 70 WP Insecticide require mixer/loader to 

wear NIOSH approved dust filtering respirators.

3. Dermal dose (mg/kg/day) = [application rate (lb ai/A) × acres treated/day × dermal unit exposure (μg/lb ai 

handled/day/1000) × dermal absorption factor (10%)] ÷ body weight (69 kg). LOC < 100.

4. Inhalation dose (mg/kg/day) = [application rate (lb ai/A) × acres treated/day × inhalation unit exposure (μg/lb ai 

handled/day/1000)] × inhalation absorption factor (100%] ÷ body weight (69 kg). LOC < 1,000. 

5. Total MOE = 1 ÷ [(1/dermal MOE) + (1/inhalation MOE)].

9.2 Short- and Intermediate-Term Post-Application Risk

HED uses the term post-application to describe exposures that occur when individuals are 

present in an environment that has been previously treated with a pesticide (also referred to as reentry exposure). Such exposures may occur when workers enter previously treated areas to 

perform job functions, including activities related to crop production, such as scouting for pests 

or harvesting. Post-application exposure levels vary over time and depend on such things as the 

type of activity, the nature of the crop or target that was treated, the type of pesticide application, 

and the chemical’s degradation properties. In addition, the timing of pesticide applications, 

relative to harvest activities, can greatly reduce the potential for post-application exposure. 

Proposed New Use

Occupational post-application activities are expected to be significantly less than residential 

post-application exposures. Dogs are expected to be treated and returned to their owners such 

that occupational post-application contact will be negligible. As a result, no quantitative 

occupational post-application exposure and risk assessment has been performed for this use. The 

residential post-application exposure and risk assessment (Section 6.0) is considered protective 

for any potential occupational post-application exposures and risks. 

Proposed Amended Use

Occupational post-application activities are anticipated for agricultural uses. 

9.2.1 Dermal Post-Application Risk

A quantitative dermal post-application assessment was conducted for the amended acetamiprid 

uses on cotton and leafy vegetables due to its use as a post-emergence foliar application 

treatment. 

Flagger

Spray with aerial Leafy 

Vegetables

SL/G 0.1 350 0.00061 18,000 0.00018 56,000 12,000

Spray with aerial Cotton 0.15 350 0.00091 11,000 0.00027 37,000 8,500
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Transfer Coefficients: It is the policy of HED to use the best available data to assess postapplication exposure. Sources of generic post-application data, used as surrogate data in the 

absence of chemical-specific data, are derived from the Agricultural Reentry Task Force (ARTF)

exposure monitoring studies and, as proprietary data, are subject to the data protection provisions 

of Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). The standard values 

recommended for use in predicting post-application exposure that are used in this assessment, 

known as “transfer coefficients,” are presented in ExpoSAC Policy 3 

(http://www.epa.gov/pesticides/science/exposac_policy3.pdf) which, along with additional 

information about the ARTF data, can be found at the Agency website

(http://www.epa.gov/pesticides/science/post-app-exposure-data.html). Table 9.2.1.1 (below) 

provides a summary of the anticipated post-application activities and associated transfer 

coefficients for the proposed crop use sites. 

For use on cotton, HED has also assessed the post-application dermal exposure and risk 

estimates for workers involved in harvesting cotton bolls. Although most of cotton harvesting is 

done mechanically, there are still some activities, with the potential for exposure, that are 

associated with the harvesting of cotton. The anticipated post-application activities, and dermal 

transfer coefficients for these activities, are presented in Table 9.2.1.1. The recommended 

transfer coefficients are derived from EPA’s Science Advisory Council for Exposure (ExpoSAC) 

Policy 3 (http://www.epa.gov/pesticides/science/exposac-policy3-march2013.pdf). 

TABLE 9.2.1.1 Anticipated Post-Application Activities and Transfer Coefficients. 

Crop Policy Crop 

Group Category

Crop 

Height

Foliage 

Density

Transfer Coefficients Activities

Cotton Field / row. crop, 

low / medium

Low Min 70 cm2/hr Weeding, Hand

Full

Min 210 cm2/hr Scouting

Full

High Min 900 g cotton boll/hr Mechanical Harvesting 

(Module Builder Operator)

2,400 g cotton boll/hr Mechanical Harvesting 

(Picker Operator and Raker)

5,050 g cotton boll/hr Mechanical Harvesting 

(Tramper)
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TABLE 9.2.1.1 Anticipated Post-Application Activities and Transfer Coefficients. 

Crop Policy Crop 

Group Category

Crop 

Height

Foliage 

Density

Transfer Coefficients Activities

Crop 

Group 4

Leafy Vegetables Low Min 70 cm2/hr Weeding, Hand &

Full Thinning Plants

Min 210 cm2/hr Scouting

Full

Min 230 cm2/hr Transplanting

Min 1,100 cm2/hr Harvesting, Hand

Full

Min 1,900 cm2/hr Hand Set Irrigation

Full

Residues: Chemical-specific dislodgeable foliar residue (DFR) data have not been submitted for 

acetamiprid. Therefore, this assessment uses HED’s default assumption that 25% of the 

application is available for transfer on Day 0 following the application, and the residues dissipate 

at a rate of 10% each following day. 

In addition, no chemical-specific data are available for the amount of residue available on the 

cotton bolls, to wit, dislodgeable boll residue (DBR) data. However, surrogate data are available 

from a study with the active ingredient tribufos (MRID #42701601). Note to RD: These data 

may trigger a data compensation issue between registrants. The residue data from this study 

were reviewed previously and found to be acceptable in risk assessment (Memo; D227007; B. 

Tarplee; 12 March 1997). The average DBR levels (μg/50 gram sample) were analyzed using 

linear regression to estimate the dissipation over time. Since the proposed acetamiprid labels 

include a 28-day PHI, the 28-day predicted cotton boll residue data for that timeframe was 

presented as surrogate data for this assessment, and then adjusted for the difference in 

application rates between the study and amended label. In addition, for characterization 

purposes, Day 0 estimates have been presented with use of the surrogate data in Table 9.2.1.2

(below). 
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TABLE 9.2.1.2 Occupational Post-application Exposure and Risk Estimates for Cotton Harvesting 

Activities.

Mechanical Harvesting 

Activity

Application 

Rate (lb ai/A)

DBR

(μg/g)1

Transfer 

Coefficient (g/hr)2

Dermal Dose3

(mg/kg/day)

Dermal 

MOE4

Day 01.a

Module Builder Operator 0.15 0.12 900 0.0013 8,000

Picker Operator and Raker 0.15 0.12 2,400 0.0033 3,000

Tramper 0.15 0.12 5,050 0.0070 1,400

Day 281.b

Module Builder Operator 0.15 0.00019 900 0.0000020 5,000,000

Picker Operator and Raker 0.15 0.00019 2,400 0.0000053 1,900,000

Tramper 0.15 0.00019 5,050 0.000011 900,000

1. Cotton Harvesting Dislodgeable Boll Residue (DBR) = [Best fit DBR at [X1.a or 1.b] days MRID# 42701601 ([X1.a 

or 1.b] μg/50g = Y μg/g) × application rate (lb ai/A)] ÷ study application rate (lb ai/A)

1.a. Best fit DBR at Day 0 is 75.55 μg/50g. DBR = (75.55 μg/50g = 0.0024 μg/g) (0.15 lb ai/A)) / (1.88 lb 

ai/A) = 0.12μg/g

1.b. Best fit DBR at Day 28 is 0.12 μg/50g. DBR = (0.12 μg/50g = 0.0024 μg/g) (0.15 lb ai/A)) / (1.88 lb 

ai/A) = 0.00019μg/g

2. From Non-Foliar Transfer Coefficient Table: http://epa.gov/pesticides/science/exposac-policy-3-march2013.pdf 

3. Daily dose (mg/kg/day) = [DBR × transfer coefficient × conversion factor (0.001 mg/μg) × dermal absorption 

factor (0.10) × 8 hours/day] ÷ body weight (69 kg). 

4: Short- and intermediate-term MOE = short-term dermal NOAEL (10 mg/kg/day) ÷ daily dose (mg/kg/day).

With the use of surrogate data, the mechanical cotton harvesting activities estimate of risk at the

PHI (Day 28) resulted in MOEs ranging from 900,000 to 5,000,000, which do not exceed the 

LOC. Even with consideration of the surrogate data at Day 0, the mechanical cotton harvesting 

activities would not result in risks of concern; MOEs ranging from 1,400 to 8,000 (see Table 

9.2.1.2). Only the highest exposure post-application activities (based on the transfer coefficient) 

for each crop were assessed for non-mechanical harvesting, as they are considered to be 

protective of all other applicable scenarios. With use of default (25%) data, scouting and hand 

set irrigation MOEs range from 1,600 to 9,800; see Table 9.2.1.3 (below). 

TABLE 9.2.1.3 Occupational Post-application Exposure and Risk Estimates for High Contact Activities 

Performed in Fields Treated with Acetamiprid.

Crop High Contact 

Activity

Application

Rate

(lb ai/A)

DFR

(ug/cm2)

Transfer 

Coefficient

(cm2/hr) 1

Dermal Dose 2 

(mg/kg/day)

Dermal 

MOE 3

Cotton Scouting 0.15 0.42 210 0.001 9,800

Leafy vegetables 

(crop group 4)

Hand-set 

Irrigation

0.1 0.28 1,900 0.006 1,600

1. Transfer coefficient is a surrogate value for workers having low-high contact with field crops foliage during postapplication activities (ExpoSAC Policy 3; 3 June 2011). 

2. Daily dose (mg/kg/day) = [DBR × transfer coefficient × conversion factor (0.001 mg/μg) × dermal absorption 

factor (0.10) × 8 hours/day] ÷ body weight (69 kg). 

3. Short-term MOE = short-term dermal NOAEL (10 mg/kg/day) ÷ daily dose (mg/kg/day).
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Acetamiprid is classified as Toxicity Category III via the dermal route, and Toxicity Category IV 

for skin irritation potential. It is not a skin sensitizer. Short- and intermediate-term postapplication risk estimates were not a concern on day 0 (12 hours following application) for all 

post-application activities. Under 40CFR §156.208[c][2], ai’s classified as Acute III or IV for 

acute dermal, eye irritation and primary skin irritation are assigned a 12-hour REI. Therefore, 

the §156 subpart K Worker Protection Statement interim REI of 12 hours is adequate to protect 

agricultural workers from post-application exposures to acetamiprid. HED would recommend a 

REI of 12 hours. This is the REI listed on the proposed labels, and is considered protective of 

post-application exposure. 

9.2.2 Inhalation Post-Application Risk

There are multiple potential sources of post-application inhalation exposure to individuals 

performing post-application activities in previously treated fields. These potential sources 

include volatilization of pesticides, and resuspension of dusts and/or particulates that contain 

pesticides. The Agency sought expert advice and input on issues related to volatilization of 

pesticides from its FIFRA Scientific Advisory Panel (SAP) in December 2009, and received the 

SAP’s final report on 2 March 2010 

(http://www.epa.gov/scipoly/SAP/meetings/2009/120109meeting.html). The agency has 

evaluated the SAP report, and has developed a Volatilization Screening Tool and a subsequent 

Volatilization Screening Analysis (http://www.regulations.gov/#!docketDetail;D=EPA-HQOPP-2014-0219). During registration review, the agency will utilize this analysis to determine if 

data (such as flux studies, route-specific inhalation toxicological studies, or further analysis) is 

required for acetamiprid. 

In addition, the Agency is continuing to evaluate the available post-application inhalation 

exposure data generated by the ARTF. Given these two efforts, the Agency will continue to 

identify the need for and, subsequently, the way to incorporate occupational post-application 

inhalation exposure into the agency's risk assessments. 

10.0 References

Acetamiprid. Request for Label Amendments for New Uses on Clover; Small Vine Climbing 

Fruits, except Kiwifruit, Subgroup 13-07F (amending grape use); Greenhouse-grown Tomatoes; 

and a Regional Registration for Tea. Summary of Analytical Chemistry and Residue Data.; 

D364833, D366269; D. McNeilly; 14 October 2009. 

Acetamiprid: Revised Human Health Risk Assessment for the New Use on Sweet Corn and 

Increased Tolerance on Citrus.; D410182; E. Holman; 20 March 2013. 

Acetamiprid - Metabolism Assessment Review Committee Briefing Memorandum; D278352; M. 

Doherty et al; 16 October 2001. 
Acetamiprid Human Health Risk Assessment D423298, D426115, D426117, D427194

Page 41 of 49

Acetamiprid. Results of the HED Metabolism Assessment Review Committee Meeting Held on 

October 16, 2001.; D278652; M. Doherty et al; 13 November 2001. 

Tier I Drinking Water Exposure Assessment for Acetamiprid in Regards to a Proposed 

Reduction in the Preharvest Interval for Clover and Hay; D423299; K. White; 25 March 2015. 

Acetamiprid. Proposed Label Amendments for Use of Two End-Use Products on Various Crops; 

Petition Proposing Label Amendments, and Revised Permanent Tolerances, for Use of the 

Insecticide on Clover with a Decreased Pre-Harvest Interval (Regional Registration). Summary 

of Analytical Chemistry and Residue Data.; D423321, D426115, D426117; W.T. Drew; 2 

September 2015. 

Acetamiprid. Acute and Chronic Dietary Exposure and Risk Assessment for Use of the 

Insecticide on Clover Grown for Seed in Idaho, Oregon and Washington Only.; D427703; W.T. 

Drew; 2 September 2015. 

Acetamiprid. Occupational and Residential Exposure Assessment for New Uses as a Pet Spot-on 

Treatment; And Increased Application Rates on Cotton, Leafy Vegetables.; D427194; J. 

Godshall; 19 August 2015. 

Acetamiprid: Human Health Risk Assessment for New Uses on Asparagus; Brassica, Leafy 

Greens, Subgroup 5B, and Turnip Greens; and Sweet Corn; and Updated Crop Group 

Definitions for Fruiting Vegetables, Citrus, and Pome Fruit.; D394322; E. Holman; 19 April 

2012. 

Acetamiprid: Occupational and Residential Exposure Assessment for Use to Control Bed Bugs; 

D383325; M. Collantes; 22 July 2011. 
Acetamiprid Human Health Risk Assessment D423298, D426115, D426117, D427194

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Appendix A. Toxicology Profile and Executive Summaries

A.1 Toxicology Data Requirements

The data requirements (40CFR §158.340) based on food use of acetamiprid are listed in Table 

A.1 (below). Use of the new guideline numbers does not imply that the new (1998) guideline 

protocols were used. 

TABLE A.1 Toxicology Data Requirements.

Study Technical

Required Satisfied

870.1100 Acute Oral Toxicity

870.1200 Acute Dermal Toxicity

870.1300 Acute Inhalation Toxicity

870.2400 Primary Eye Irritation

870.2500 Primary Dermal Irritation

870.2600 Dermal Sensitization

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

870.3100 Oral Subchronic (rodent)

870.3150 Oral Subchronic (non-rodent)

870.3200 21-Day Dermal

870.3250 90-Day Dermal

870.3465 21/28-Day Inhalation

Yes

Yes

Yes

No

No

Yes

Yes

Yes

--

--

870.3700a Developmental Toxicity (rodent)

870.3700b Developmental Toxicity (non-rodent)

870.3800 Reproduction

Yes

Yes

Yes

Yes

Yes

Yes

870.4100a Chronic Toxicity (rodent)

870.4100b Chronic Toxicity (non-rodent)

870.4200a Oncogenicity (rat)

870.4200b Oncogenicity (mouse)

870.4300 Chronic/Oncogenicity

Yes

Yes

Yes

Yes

Yes 

Yes

Yes

Yes

Yes

Yes 

870.5100 Mutagenicity—Gene Mutation - bacterial

870.5300 Mutagenicity—Gene Mutation - mammalian

870.5xxx Mutagenicity—Structural Chromosomal Aberrations

870.5xxx Mutagenicity—Other Genotoxic Effects

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

870.6100a Acute Delayed Neurotoxicity (hen)

870.6100b 90-Day Neurotoxicity (hen)

870.6200a Acute Neurotoxicity Screening Battery (rat)

870.6200b 90-Day Neurotoxicity Screening Battery (rat)

870.6300 Develop. Neurotoxicity

No

No

Yes

Yes

Yes

--

--

Yes

Yes

Yes

870.7485 General Metabolism

870.7600 Dermal Penetration

870.7800 Immunotoxicity

Yes

Yes

Yes 

Yes

Yes

Yes 
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A.2 Toxicity Profiles

TABLE A.2.1 Acute Toxicity Profile for Technical Acetamiprid.

Guideline Study Type MRID # Results Tox Category

870.1100 Acute Oral - rat 44651833 LD50: 217 mg/kg (M)

LD50: 146 mg/kg (F)

II

870.1200 Acute Dermal - rat 44651836 LD50 > 2000 mg/kg III

870.1300 Acute Inhalation - rat 44651837 LC50: > 1.15 mg/L (~)

> 1.15 mg/L (~)

III

870.2400 Primary Eye Irritation - rabbit 44651838 Not irritating to the eye IV

870.2500 Primary Skin Irritation - rabbit 44651839 Not irritating to the skin IV

870.2600 Dermal Sensitization - Guinea pig 44651840 Not a sensitizer under 

conditions of the study.

Not applicable

TABLE A.2.2 Subchronic, Chronic and Other Toxicity Profile for Acetamiprid.

Guideline Number,

Study Type

MRID Number (Year), 

Classification and Doses

Results

870.3100

90-Day oral toxicity –

rat

(dietary)

44651843 (1997)

Acceptable/guideline

0, 50, 100, 200, 800, 1600 ppm

0/0, 3.1/3.7, 6.0/7.2, 12.4/14.6, 

50.8/56.0, 99.9/117 (M/F) 

mg/kg/day

NOAEL = 12.4/14.6 (M/F) mg/kg/day 

LOAEL = 50.8/56.0 mg/kg/day (M/F) based on 

decreased BW, BW gain and food consumption

870.3100

90-Day feeding –

mouse

44988425 (1997)

Acceptable/guideline

0, 400, 800, 1600, 3200 ppm

0/0, 53.2/64.6, 106.1/129.4, 

211.1/249.1, 430.4/466.3 (M/F) 

mg/kg/day

NOAEL = 106.1/129.4 (M/F) mg/kg/day 

LOAEL = 211.1/249.1 (M/F) mg/kg/day based on 

reduced BW and BW gain, decreased glucose and 

cholesterol levels, reduced absolute organ weights

870.3150

90-Day oral toxicity –

dog

(dietary)

44988424 (1998)

Acceptable/guideline 

0, 320, 800, 2000 ppm

0/0, 13/14, 32/32, 58/64 (M/F) 

mg/kg/day

NOAEL = 13/14 (M/F) mg/kg/day 

LOAEL = 32 mg/kg/day based on reduced BW gain 

in both sexes

870.3200

21-Day dermal toxicity

– rabbit

44651844 (1997)

Acceptable/guideline

0, 100, 500, 1000 mg/kg/day

Systemic NOAEL = 1000 mg/kg/day 

LOAEL = not determined

Dermal NOAEL = 1000 mg/kg/day

LOAEL = not determined 
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TABLE A.2.2 Subchronic, Chronic and Other Toxicity Profile for Acetamiprid.

Guideline Number,

Study Type

MRID Number (Year), 

Classification and Doses

Results

870.3700

Developmental toxicity 

– rat

(gavage)

44651847 (1997)

Acceptable/guideline

0, 5, 16, 50 mg/kg/day

Maternal:

NOAEL = 16 mg/kg/day

LOAEL = 50 mg/kg/day based on reduced BW & 

BW gain and food consumption, increased liver 

weights

Developmental:

NOAEL = 16 mg/kg/day 

LOAEL = 50 mg/kg/day based on increased 

incidence of shortening of the 13th rib

870.3700

Developmental toxicity 

– rabbit

(gavage)

44651848 (1997)

Acceptable/guideline

0, 7.5, 15, 30 mg/kg/day

Maternal:

NOAEL = 15 mg/kg/day

LOAEL = 30 mg/kg/day (BW loss and decreased 

food consumption).

Developmental:

NOAEL = 30 mg/kg/day (HDT) 

LOAEL = not determined

870.3800

Reproduction and 

fertility effects – rats

(dietary)

44988430 (1999)

Acceptable/guideline

0, 100, 280, 800 ppm

Parental animals

0/0, 6.5/7.6, 17.9/21.7, 51.0/60.1 

(M/F) mg/kg/day

F1 animals

0/0, 7.5/8.4, 21.0/23.8, 63.3/72.6 

(M/F) mg/kg/day

Parental/Systemic:

NOAEL = 17.9/21.7 (M/F) mg/kg/day 

LOAEL = 51.0/60.1 (M/F) mg/kg/day based on 

decreased body weight, body weight gain and food 

consumption

Offspring:

NOAEL = 17.9/21.7 (M/F) mg/kg/day 

LOAEL = 51.0/60.1 (M/F ) mg/kg/day based on 

reductions in pup weight, litter size, viability and 

weaning indices; delay in age to attain preputial 

separation and vaginal opening

Reproductive:

NOAEL = 17.9/21.7 (M/F) mg/kg/day 

LOAEL = 51.0/60.1 (M/F) mg/kg/day based on 

reductions in litter weights and individual pup 

weights on day of delivery

870.4100

Chronic toxicity – rat 

Same as Chronic 

Toxicity/Carcinogenicity- rat see 

below (870.4300)

See below (870.4300)

870.4100

Chronic toxicity – dog 

(dietary)

44651846 (1998)

Acceptable/guideline

0, 240, 600, 1500 ppm

0/0, 9/9, 20/21, 55/61 (M/F) 

mg/kg/day

NOAEL = 20/21 (M/F) mg/kg/day 

LOAEL = 55/61 (M/F) mg/kg/day based on initial 

BW loss and overall reduction in BW gain
Acetamiprid Human Health Risk Assessment D423298, D426115, D426117, D427194

Page 45 of 49

TABLE A.2.2 Subchronic, Chronic and Other Toxicity Profile for Acetamiprid.

Guideline Number,

Study Type

MRID Number (Year), 

Classification and Doses

Results

870.4200

Carcinogenicity –

mouse

(dietary)

44988428, 45245305 (1999) 

Acceptable/guideline

0, 130, 400, 1200 ppm (equivalent 

to 0/0, 20.3/25.2, 65.6/75.9, 

186.3/214.6 mg/kg/day in 

males/females)

NOAEL = 20.3/75.9 mg/kg/day (M/F)

LOAEL = 65.6/214.6 (M/F ) mg/kg/day based on 

decreased BW & BW gain and amyloidosis in 

numerous organs (M) and decreased BW and BW 

gain (F)

Not oncogenic under conditions of study

870.4300

Chronic/

Carcinogenicity – rat 

44988429, 45245304 (1999)

Acceptable/guideline

0, 160, 400, 1000 ppm

(equivalent to 0/0, 7.1/8.8, 

17.5/22.6, 46.4/60.0 (M/F) 

mg/kg/day)

NOAEL = 7.1/8.8 (M/F) mg/kg/day 

LOAEL = 17.5/22.6 mg/kg/day (M/F) based on 

decreases in mean BW & BW gain (F) and 

hepatocellular vacuolation (M)

Evidence of treatment-related increase in mammary 

tumors, not considered treatment-related

870.5100

Salmonella 

typhimurium/E. coli

Reverse gene mutation 

assay

44651849 (1997)

Acceptable/guideline

313 to 5000 μg ai/plate incubated 

65.5 hours with +/- S9

Not mutagenic under the conditions of the study

870.5300

Mammalian cells in 

culture

Forward gene mutation 

assay – CHO cells

44651857 (1998)

Acceptable/guideline

500-4000 ug/mL –S9 or 250-

3000ug/mL + S9

Not mutagenic under the conditions of the study.

870.5375

In vitro mammalian 

chromosome aberration 

test – Chinese hamster 

ovary (CHO) cells

44651855 (1997)

Acceptable/guideline

175, 350, 700 μg/mL - S9 or 338, 

675, 1350 ug/mL + S9 (Highest 

doses slight to moderately 

cytotoxic).

Acetamiprid is a clastogen under the conditions of 

the study.

870.5385

In vivo mammalian 

chromosome 

aberrations – rat bone 

marrow

44651854 (1998)

Acceptable/guideline

250 mk/kg (maximum tolerated 

dose)

Bone marrow analyzed at 6, 24, 

and 48 hours.

Acetamiprid did not induce a significant increase in 

chromosome aberrations in bone marrow cells when 

compared to the vehicle control group.

870.5395

In vivo mammalian 

cytogenetics –

micronucleus assay in 

mice

44651852 (1998)

Acceptable/guideline

20, 40, 80 mg/kg

Bone marrow analyzed at 24, 48, 

or 72 hours

Acetamiprid is not a clastogen in the mouse bone 

marrow micronucleus test.
Acetamiprid Human Health Risk Assessment D423298, D426115, D426117, D427194

Page 46 of 49

TABLE A.2.2 Subchronic, Chronic and Other Toxicity Profile for Acetamiprid.

Guideline Number,

Study Type

MRID Number (Year), 

Classification and Doses

Results

870.5550 

Unscheduled DNA 

synthesis in primary rat 

hepatocytes, 

mammalian cell culture

44651856 (1998)

Acceptable/guideline

0.5 to 1000 μg/mL

Acetamiprid tested negatively for UDS in 

mammalian hepatocytes in vivo.

870.6200a

Acute neurotoxicity 

screening battery – rat

(gavage)

44651842 (1997) 

Acceptable/guideline

0, 10, 30, 100 mg/kg

Neurotoxicity:

NOAEL= 10 mg/kg/day

LOAEL = 30 mg/kg based on reduction in 

locomotor activity

870.6200b

Subchronic 

neurotoxicity screening 

battery – rat

(dietary)

44651845 (1997)

Acceptable/guideline

0, 100, 200, 800, 1600 ppm

(equivalent to 0/0, 7.4/8.5, 

14.8/16.3, 59.7/67.6, 118/134 

mg/kg/day)

Neurotoxicity:

NOAEL= 14.8/16.3 mg/kg/day (M/F)

LOAEL = 59.7/67.6 (M/F) mg/kg/day based on 

reductions in BW, BW gain, food consumption and 

food efficiency

870.6300

Developmental 

neurotoxicity – rat 

(gavage)

46255619 (2003)

Acceptable/Non-Guideline

0, 2.5, 10, 45 mg/kg/day 

Volume: 5 mL/kg

Vehicle: 5% gum Arabic with 

0.01% Tween 80 

Maternal:

NOAEL = 10 mg/kg/day

LOAEL = 45 mg/kg/day based on decreased body 

weight and body weight gains during gestation only

Offspring:

NOAEL = 10 mg/kg/day. 

LOAEL = 45 mg/kg/day based on decreased 

maximum auditory startle response in males on 

PND 20 and PND 60, and decreased body weight 

and body weight gain, and pup viability

870.7485

Metabolism and 

pharmacokinetics – rat

44988503-7 (1997)

Acceptable/guideline

Single dose study with 1 mg/kg 

(iv), 1 or 50 mg/kg (gavage) 

15-day repeated doses study with 

1 mg/kg (gavage); Biliary 

excretion study with 1 mg/kg 

(gavage)

Extensively and rapidly metabolized. Metabolites 

79-86% of administered dose. Profiles similar for 

males and females for both oral and intravenous 

dosing. Thirty-seven percent of dose recovered in 

urine and feces as unchanged test article. Urinary 

and fecal metabolites from 15-day repeat dose 

experiment only showed minor differences from 

single-dose test. Initial Phase I biotransformation: 

demethylation of parent. 6-chloronicotinic acid was 

the most prevalent metabolite. Phase II metabolism 

shown by the increase in glycine conjugate.
Acetamiprid Human Health Risk Assessment D423298, D426115, D426117, D427194

Page 47 of 49

TABLE A.2.2 Subchronic, Chronic and Other Toxicity Profile for Acetamiprid.

Guideline Number,

Study Type

MRID Number (Year), 

Classification and Doses

Results

870.7485

Metabolism – mouse, 

rat, rabbit

Special study

Male mice, rats or rabbits were administered single 

doses of acetamiprid by gavage, intraperitoneal 

injection (i.p.) or intravenous injection (i.v.) up to 60 

mg/kg. The animals were assessed for a variety of 

neurobehavioral parameters. In vitro experiments 

were also done using isolated ileum sections from 

guinea pigs to assess contractile responses in the 

absence and presence of agonists (acetylcholine, 

histamine diphosphate, barium chloride and nicotine 

tartrate). Acetamiprid was also assessed via i.v. in 

rabbits for effects on respiratory rate, heart rate and 

blood pressure; via gavage in mice for effects on 

gastrointestinal motility; and via i.p. in rats for 

effects on water and electrolyte balance in urine, and 

blood coagulation, hemolytic potential and plasma 

cholinesterase activity. Based on a number of 

neuromuscular, behavioral and physiological 

effects of acetamiprid in male mice, under the 

conditions of this study, an overall NOAEL of 10 

mg/kg (threshold) and LOAEL of 20 mg/kg could 

be estimated for a single dose by various 

exposure routes.

870.7600

Dermal penetration –

rat

44651858 (1997)

Acceptable/non-guideline 

1.09, 9.53, 90.2 ug/cm2

Absorption was highest at the mid-dose and 

increased with duration (4.07% at 10 after 10 hours 

and 6.34% after 24 hours). Residue remaining in 

the skin at 24 hours is 25.0%. In addition to 

absorbed dose (6.34%), total absorption is estimated 

at 30%. Discuss revised dermal absorption briefly 

here or refer to dermal abs. section

870.7800

Immunotoxicity – rat

(dietary)

48113402 (2010)

acceptable/guideline

0, 100, 300, 900 ppm

Equivalent to 0/0, 7.4/8.6, 

21.6/24.3, 62.9/67.7 (M/F) 

mg/kg/day

Systemic:

NOAEL = 21.6/24.3 (M/F) mg/kg/day

LOAEL = 62.9/67.7 (M/F) mg/kg/day based on 

decreases in body weight, body weight gain, food 

consumption and water consumption (males only).

Immunotoxicity:

NOAEL = 62.9/67.7 (M/F) mg/kg/day

LOAEL = not attained
Acetamiprid Human Health Risk Assessment D423298, D426115, D426117, D427194

Page 48 of 49

TABLE A.2.2 Subchronic, Chronic and Other Toxicity Profile for Acetamiprid.

Guideline Number,

Study Type

MRID Number (Year), 

Classification and Doses

Results

870.7800

Immunotoxicity –

mouse (dietary)

48113401 (2010)

acceptable/guideline

0, 100,300, 900 ppm

Equivalent to 0/0, 15.3/20.2, 

47.0/54.4, 128/157 (M/F) 

mg/kg/day

Systemic:

NOAEL = 47.0/54.4 (M/F) mg/kg/day

LOAEL = 128/157 (M/F) mg/kg/day based on 

decreases in body weight (slight), body weight gain, 

food consumption and water consumption (males 

only)

Immunotoxicity:

NOAEL = 128/157 (M/F) mg/kg/day

LOAEL = not attained

N/A

28-Day Range-finding 

Study – dog

(dietary)

45245306 (1998)

Acceptable/Non-guideline

0, 125/3000, 250, 500, 1000 ppm

mg/kg/day: M= 0, 4.1/42.5, 8.4, 

16.7, 28.0; F= 0, 4.8/46.2, 8.7, 

19.1, 35.8 [ppm: 125/3000 = 125 

for 2 weeks, 3000 for 2 weeks]

NOAEL = 16.7/19.1 (M/F) mg/kg/day 

LOAEL = 28.0/35.8 (M/F) mg/kg/day based on 

reduced BW gain
Acetamiprid Human Health Risk Assessment D423298, D426115, D426117, D427194

Page 49 of 49

Appendix B. Physicochemical Properties

TABLE B.1 Physicochemical Properties of Technical-Grade Acetamiprid.

Parameter Value Reference

Melting Point/Range (C) 98.9 D328216; W.T. Drew; 23 October2007

pH 6.08 (Aqueous solution at 20C)

Density (g/cm3) 1.33 (at 20C)

Water Solubility (g/L) 4.25 (at 25C)

Solvent Solubility (at 25C) Acetone >20 g/100 g

Methanol >20 g/100 g

Ethanol >20 g/100 g

Dichloromethane >20 g/100 g

Chloroform >20 g/100 g

Acetonitrile >20 g/100 g

Tetrahydrofuran >20 g/100 g

Benzene 2.44 g/100 g

Xylene 4.01 g/100 g

n-Hexane 6.54 ppm

Carbon disulfide 507 ppm

Vapor Pressure (mm Hg) 7.5 x 10-9

(at 25C) D264154; M. Doherty; 31 December 

2001

Dissociation Constant, pKa 0.7 (at 25C) D328216; W.T. Drew; 23 October2007

Octanol/Water Partition 

Coefficient, Log KOW

0.8 (at 25C)

UV/Visible Absorption Spectrum Not available