1123/14 

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

OFFICE OF CHEMICAL SAFETY 

AND POLLUTION PREVENTION 

MEMORANDUM 

SUBJECT: Fosetyi-Aiuminum: Registration Review Preliminary Risk Assessment 

PC Code: 123301; 0 416436 

PC Code: 123301 

Decision Nos.: 485442 

Petition Nos.: NA 

DP Barcodes: 416436 

Registration Nos.: NA 

Regulatory Action: Registration Review 

Risk Assessment Type: Single Chemical Case No.: 0646-1 

Aggregate 

TXRNo.: NA CAS No.: 39148-24-8 

MRIDNo.: NA 40 CFR: 180.415 

FROM: 

THROUGH: 

TO: 

DonnaS. Davis, Chemist & Risk Assesso 

Matthew Lloyd, CIH, Indu rial Hyg· nist i.-/. tw_7_ Linda Taylor, Toxicologist ~A-~C- Registration Assessment B ch VII 

Heath Effects Division (7509P) 

Alexandra LaMay, Biologist ~~ MichaelS. Metzger, Branch Chief 

Registration Assessment Branch 

Health Effects Division (7509P) 

Kelly Ballard, Chemical Review Manager 

Neil Anderson, Chief 

Risk Management and Implementation Branch I 

Pesticide Re-evaluation Division (7508P) 

Attached please find the Health Effects Division's Preliminary Risk Assessment (PRA) for the 

active ingredient, fosetyl-Aluminum. 

Page 1 of36 
Page 2 of 36

EXECUTIVE SUMMARY

The Health Effects Division (HED) has evaluated the current databases for the active ingredient 

fosetyl-aluminum (fosetyl-Al) to support the registration review of this active ingredient. 

Fosetyl-Al is a systemic fungicide which is effective against diseases caused by the Oomycetes 

(phytophthora and downy mildews). It is registered for foliar use by ground and air application 

to a wide range of agricultural crops and for root dip, bark injection, and citrus trunk painting, as 

well as for use on pea as a seed treatment. Fosetyl-Al is also registered for use on ornamental 

plants in residential areas, and is registered for use on turf grass on golf courses, and commercial 

turf areas where residential post application exposure may occur. The only new data considered 

in this assessment was a previously unreviewed succulent pea storage stability study. That study 

is scientifically acceptable and adequate to address the standing storage stability data gap. No 

change to the current succulent pea tolerance is required based on these data. The toxicity, 

residue chemistry, and occupational/residential exposure databases are considered complete at 

this time. The hazard and exposure profiles for this active ingredient are adequately understood. 

There are no dietary (food and water), residential, aggregate, or occupational risks of concern 

associated with fosetyl-Al.

Regulatory Recommendation

There are no human health risks of concern identified for fosetyl-Al. 

HED has evaluated the current tolerances established for fosetyl-Al and recommends the 

following revisions to the 40CFR 180.415 to harmonize with established international tolerances 

and to reflect the most updated crop grouping definitions:

 The current caneberry subgroup 13A tolerance at 0.1 ppm should be replaced with a 

tolerance for the caneberry subgroup 13-07A. HED recommends that the tolerance level 

for the crop group be reduced to 0.05 ppm to harmonize with Canadian MRLs and 

address U.S./Canadian grower priority for blueberries. 

 The current bushberry subgroup 13B tolerance at 40 ppm should be replaced with 

bushberry subgroup 13-07B tolerance at 40 ppm.

 The current citrus fruit group 10 tolerance of 5.0 ppm should be replaced with a citrus 

fruit group 10-10 tolerance. HED has no objection to raising the tolerance from its 

current level of 5.0 ppm to 9 ppm to harmonize with the Canadian MRL. 

 The current pome fruit group 11 tolerance of 10 ppm should be replaced with a pome 

fruit group 11-10 tolerance at 10 ppm.

 Reduce the current ginseng tolerance of 0.1 ppm to 0.05 ppm to harmonize with the 

Canadian MRL.

HED has evaluated the appropriate restricted entry interval (REI) for fosetyl-Al and makes the 

following recommend revision to the product labels:
Page 3 of 36

 Existing product labels should be amended to reflect a 48-hour REI. Technical fosetyl-Al 

falls into Toxicity Category I for primary eye irritation. Per the Worker Protection 

Standard (WPS), a 48-hour REI is required for chemicals classified under Toxicity 

Category I. 

For the seed treatment use (SLN ID-30001), HED recommends adding the appropriate seed 

treatment language. The labeling should state: Seed that has been treated with this product that 

is then packaged or bagged for future use must contain the following labeling on the outside of 

the seed package or bag:

"Treated Seed - Do Not Use for Food, Feed, or Oil Purposes.

When opening this bag or loading/pouring the treated seed, wear a long-sleeved 

shirt, long pants, shoes, socks, and chemical resistant gloves. After the seeds have 

been planted, do not enter or allow worker entry into treated areas during the 

restricted-entry interval (REI) of 48 hours. Exception: Once the seeds are planted 

in soil or other planting media, the Worker Protection Standard allows workers to 

enter the treated area without restriction if there will be no worker contact with 

the treated seeds in the soil or planting media."

INTRODUCTION

Fosetyl-Al is a systemic fungicide which is effective against diseases caused by the Oomycetes 

(phytophthora and downy mildews). The fungicide is currently registered for use on a wide 

variety of agricultural crops and on ornamental plants and turf. 

The most recent comprehensive human health risk assessments for fosetyl-Al were developed to 

support new uses on turnips, succulent peas, citrus fruit group, leeks, green onions and the 

bushberry subgroup (D279163, M. Rust, 5/17/01). In 2007, HED completed a Scoping 

Document that evaluated the available data and risk assessments for fosetyl-Al (D340101, D. 

Davis, 8/15/07) and concluded that no new data were needed to support the registration review of 

this active ingredient. The Scoping Document did note that succulent pea storage stability data 

had been submitted to HED. This data needed review and the adequacy of the current succulent 

pea tolerance needed evaluation under registration review. These needs have been addressed in 

this risk assessment. 

HAZARD CONSIDERATIONS

No new toxicity and/or rat metabolism data have been received since the last risk assessment and 

scoping document were completed. Neither of those documents identified any data deficiencies 

with respect to toxicology. However, based on the current 40 CFR Part 158 data requirements, 

an immunotoxicity study, a subchronic inhalation toxicity study, and acute and subchronic 

neurotoxicity studies may now be required for fosetyl-Al. As part of developing a preliminary 

risk assessment during registration review, the Hazard and Science Policy Council (HASPOC) 

reviewed the database for fosetyl-Al and concluded that these studies are not required. (TXR 
Page 4 of 36

No. 0056809, dated October 29, 2013). Consequently there have been no changes to the 

toxicological endpoints and safety factors/uncertainty factors for human health risk assessment 

from the most recent assessment referenced above. 

The toxicological database for fosetyl-Al is considered complete for characterization of potential 

developmental, reproductive, carcinogenetic, mutagenic, neurotoxic, and immunotoxic effects. 

Fosetyl Al is rapidly metabolized following oral exposure and widely distributed, and it is 

primarily excreted via the respiratory route (as CO2) and in the urine, mainly as phosphorous 

acid. The major target organs following repeated oral exposure to fosetyl-Al are the reproductive 

system in the dog (testicular degeneration: spermatocytic and/or spermatidic giant cells in the 

lumen of the seminiferous tubules) and the urinary system in the rat (histopathological changes 

in the kidney, impairment of calcium/phosphorus metabolism, calculi and hyperplasia in the 

urinary tract, bladder tumors). There is no concern for increased quantitative or qualitative 

susceptibility of the young following in utero (rats and rabbits) and pre-and post-natal exposure 

(rats) to fosetyl-Al. Also, there is no evidence of developmental toxicity, reproductive toxicity, 

neurotoxicity, or immunotoxicity at dose levels that do not exceed the limit dose. The Food 

Quality Protection Act (FQPA) safety factor has been reduced to 1X. Fosetyl-Al is negative for 

carcinogenicity except at extremely high doses (>limit dose) in rats and mice, and it did not show 

any genotoxic potential (classified as not likely to pose a carcinogenic hazard to humans). 

Fosetyl-Al is not acutely toxic via the oral, dermal, and inhalation routes. It produces severe eye 

irritation, is not a dermal irritant, and is negative for dermal sensitization.

The fosetyl-Al toxicity profile tables are included in this memo in Appendix A. The toxicity 

endpoints for risk assessment are shown in Tables 1 and 2.

Table 1. Summary of Toxicological Doses and Endpoints for Fosetyl-Al for Use in Dietary and NonOccupational Human Health Risk Assessments

Exposure/ 

Scenario

Point of 

Departure

Uncertainty/FQPA 

Safety Factors

RfD, PAD, 

Level of 

Concern for 

Risk 

Assessment

Study and Toxicological Effects

Acute Dietary 

(All 

populations)

No hazard or appropriate acute endpoint was identified in the database. There are no 

developmental concerns. HASPOC determined that an ACN is not required (TRX No. 0056809, 

dated October 29, 2013).

Chronic 

Dietary (All 

Populations)

NOAEL = 

250 

mg/kg/day

UFA 10x

UFH 10x

FQPA SF = 1X

cRfD = 

2.5mg/kg/day

cPAD = 2.5 

mg/kg/day

Chronic oral toxicity (dog)

MRID 00098340 (1981)

LOAEL = 500 mg/kg/day, based on an 

increased incidence of testicular 

degeneration ( spermatocytic and/or 

spermatidic giant cells in the lumen of the 

seminiferous tubules)

Dermal (All 

durations)

No potential hazard via the dermal route, based on the lack of systemic effects following repeat 

dermal exposure of rabbits at dose levels up to 1500 mg/kg/day, which is greater than the limit 

dose. The endpoints of concern were all assessed in this study, and there is no developmental or 

reproductive concern at dose levels that exceed the limit dose.
Page 5 of 36

Table 1. Summary of Toxicological Doses and Endpoints for Fosetyl-Al for Use in Dietary and NonOccupational Human Health Risk Assessments

Exposure/ 

Scenario

Point of 

Departure

Uncertainty/FQPA 

Safety Factors

RfD, PAD, 

Level of 

Concern for 

Risk 

Assessment

Study and Toxicological Effects

Incidental Oral

(Short- and 

IntermediateTerm)

NOAEL = 

300 

mg/kg/day

UFA 10x

UFH 10x

FQPA SF = 1x

Residential

LOC for

MOE < 100

3-generation reproduction (rat)

MROD 00098352 (1981)

LOAEL = 600 mg/kg/day, based on 

decreased body weight gains in the F2b 

generation and urinary tract changes in 

adults

Inhalation 

(Short- and 

IntermediateTerm) 

NOAEL = 

300 

mg/kg/day

UFA 10x

UFH 10x

FQPA SF = 1x

Residential 

LOC for 

MOE < 100

3-generation reproduction (rat)

MRID 00098352 (1981)

LOAEL = 600 mg/kg, based on decreased 

body weight gains in the F2b generation 

and urinary tract changes in adults.

Inhalation 

Long-Term (> 

6 months)

NOAEL = 

250 

mg/kg/day

UFA 10x

UFH 10x

FQPA SF = 1x

Residential 

LOC for 

MOE < 100

Chronic oral toxicity (dog) 

MRID 00098340 (1981)

LOAEL = 500 mg/kg/day, based on an 

increased incidence of testicular 

degeneration (spermatocytic and/or 

spermatidic giant cells in the lumen of the 

seminiferous tubules)

Cancer (oral, 

dermal, 

inhalation)

Classification: Not likely to pose a carcinogenic hazard to humans

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. PAD = 

population adjusted dose (a = acute, c = chronic). RfD = reference dose. MOE = margin of exposure. LOC = level 

of concern. N/A = not applicable.

Table 2. Summary of Toxicological Doses and Endpoints for Fosetyl-Al for Use in Occupational Human 

Health Risk Assessments

Exposure/ 

Scenario

Point of 

Departure

Uncertainty 

Factors

Level of Concern 

for Risk 

Assessment

Study and Toxicological Effects

Dermal (All 

durations)

No potential hazard via the dermal route, based on the lack of systemic effects following repeat 

dermal exposure of rabbits at dose levels up to 1500 mg/kg/day, which is greater than the limit 

dose. The endpoints of concern were all assessed in this study, and there is no developmental or 

reproductive concern at dose levels that do not exceed the limit dose.

Inhalation 

(Short- and 

IntermediateTerm )

NOAEL = 

300 

mg/kg/day

UFA 10x

UFH 10x

FQPA SF = 

1x

Occupational 

LOC for MOE < 

100

3-generation reproduction (rat)

MRID 00098352 (1981) 

LOAEL = 600 mg/kg, based on decreased 

body weight gains in the F2b generation 

and urinary tract changes in adults.
Page 6 of 36

Table 2. Summary of Toxicological Doses and Endpoints for Fosetyl-Al for Use in Occupational Human 

Health Risk Assessments

Exposure/ 

Scenario

Point of 

Departure

Uncertainty 

Factors

Level of Concern 

for Risk 

Assessment

Study and Toxicological Effects

Inhalation 

Long-Term (> 

6 months)

NOAEL = 

250 

mg/kg/day

UFA 10x

UFH 10x

FQPA SF = 

1x

Residential LOC 

for MOE < 100

Chronic oral toxicity (dog) 

MRID 00098340 (1981)

LOAEL = 500 mg/kg/day, based on an 

increased incidence of testicular

degeneration (spermatocytic and/or 

spermatidic giant cells in the lumen of the 

seminiferous tubules)

Cancer (oral, 

dermal, 

inhalation)

Classification : Not likely to pose a carcinogenic hazard to humans

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). MOE = margin of exposure. LOC = level of 

concern. 

RESIDUE CHEMISTRY CONSIDERATIONS

Fosetyl-Al is registered on a wide variety of agricultural crops including: avocado; banana; 

blueberry; bushberries; caneberries; cranberry; citrus fruits; pome fruits; ginseng; hops; 

juneberry; leafy vegetables; lingonberry; macadamia nuts; green and dry bulb onions; succulent 

peas; pineapple; salal; strawberry; tomato; turnip; cucurbits; and tobacco. Additionally, fosetylAl is regionally registered application on asparagus, avocado, strawberry, almond, walnuts, pome 

fruit and hops, as well as for use as a bark injection on citrus and for use on pea seed. 

Formulations include wettable powder, water dispersible granules, emulsifiable concentrate and 

ready-to-use liquid. Typical application is multiple foliar applications of up to 4.0 lbs 

ai/A/application for seasonal totals ranging from 16 to 28 lbs ai/A with pre-harvest intervals 

(PHIs) ranging from 60 days to 0 days. 

The most recent residue chemistry reviews for fosetyl-Al were developed to support new uses on 

turnips, succulent peas, and citrus (D272047, A. Acierto, 2/28/02), leeks and green onions 

(D279385, A. Acierto, 2/21/02) and on tobacco (D277604, N. Dodd, 8/2/05). No new residue 

chemistry data have submitted subsequent to issuance of the HED Scoping Document in 2007. 

At the time of the scoping document, HED considered the residue chemistry database complete, 

but noted that succulent pea storage stability data submitted to the Agency should be reviewed to 

support the registration review of fosetyl-Al. The structure of fosetyl-Al and the 

physical/chemical properties are contained in Appendix B, Table B1.

HED reviewed the submitted succulent pea storage stability data (45820301.der.doc, D. Davis, 

1/16/14). The study was found to be scientifically acceptable. Adequate documentation of the 

field and analytical phases of the study was provided. The storage stability period adequately 

reflects the duration of frozen storage of the original succulent pea field trial samples (MRID No. 

45224702). The data indicate that residues of fosetyl-Al are not stable in pea seed stored at ≤ -
Page 7 of 36

20°C for more than 30 days. After 90 days of frozen storage, residues in pea seed had declined 

by 41%. 

HED considered the previously submitted succulent pea field trial data (MRID No. 45224702, 

D272047, A. Acierto, 2/28/02) in light of the new storage stability data to determine if the 

current succulent pea tolerance is adequate. Residues in pea samples from field trials (average of 

replicates) ranged from <0.05 ppm to 0.16 ppm. The residue data were developed using the 

maximum application rate, minimum retreatment intervals and minimum PHI. All pea samples 

were stored for less than 90 days, the period of the submitted storage stability study. When the 

maximum residue seen in the field trials was corrected for potential loss due to frozen storage, 

the corrected residue did not exceed the current tolerance of 0.3 ppm. Furthermore, most of the 

corrected residues from were significantly lower than the maximum residue value from the 

study. Therefore, HED concludes that the current tolerance for succulent pea is adequate and the 

tolerance may remain at 0.3 ppm, a value which is harmonized with the current Canadian MRL. 

The residue chemistry database is adequate to support the registration review of the currently 

registered uses for fosetyl-Al. Findings with respect to residue chemistry have not changed from 

the most recent residue chemistry summary documents. The nature and magnitude of the residue 

in plants, livestock and rotated crops is adequately understood. Adequate data have been 

provided on processed commodities. Analytical methods and reference standards are available 

to support the established tolerances. 

INTERNATIONAL HARMONIZATION/TOLERANCE CONSIDERATIONS

International Harmonization

The International Residue Limits Status Sheet is attached to this memorandum in Appendix B. 

There are no Codex MRLs for fosetyl-Al. The U.S. and Canada regulate residues of fosetyl-Al

based on the same tolerance expression. Actual tolerance/MRL values are harmonized for all 

crops with the exception of the following:

 Blackberries, loganberries, raspberries, wild raspberries. PMRA has established MRLs 

of 0.05 ppm for these crops; the U.S. has established a crop subgroup tolerance which 

includes these commodities at 0.1 ppm.

Blackberries have been identified as a US/Canadian grower priority; consequently, HED 

reviewed the available data used to support the original caneberry tolerance (MRID No. 

4074701, M. Nelson, 4/19/89). All caneberry residues were less than the method limit of 

quantitation (<LOQ) of 0.05 ppm. Therefore, HED has no objection to lowering the U.S. 

tolerance for caneberry to 0.05 ppm in order to allow harmonization for all caneberries, including 

black berries.

 Citrus fruit crop group. PMRA has established an MRL of 9 ppm while the U.S. has a 

crop group tolerance of 5.0 ppm.

HED has no objection to increasing the tolerance on the citrus fruit crop group to 9 ppm in order 
Page 8 of 36

to harmonize tolerance/MRL levels with Canada. The increase is considered to be appropriate 

for international harmonization, but will have no impact on U.S. dietary exposure since the field 

trial data reflecting the maximum label application rate and a 0-day PHI (D272047, A. Acierto, 

2/28/02) are well below the current tolerance of 5.0 ppm and would not be expected to increase 

based solely on the increase in a tolerance level. 

 Apples. PMRA has established an MRL of 1 for apples; the US has a pome fruit crop 

group tolerance, which includes apples at 10 ppm.

Residue data submitted to support the current U.S. tolerance include samples with residues in 

excess of the 1 ppm MRL established in Canada (PP8F3689, R. Cook, 2/21/89). Since residues 

from the currently registered use are likely to exceed the Canadian MRL, harmonization is not 

possible at this time. 

 Ginseng. PMRA has a ginseng root tolerance of 0.05 ppm, the U.S. has a ginseng 

tolerance of 0.1 ppm. 

HED has reviewed the available residue data for ginseng. All ginseng residues were <LOQ of 

0.05 ppm (1E3948, M. Nelson, 11/19/91). Therefore, HED has no objection to lowering the U.S. 

tolerance for ginseng to 0.05 ppm in order to allow harmonization with Canadian ginseng MRL.

Crop Group/Subgroup Updates

In order to update the 40 CFR to reflect the most recent crop grouping scheme, HED 

recommends the following crop group/subgroup revisions:

 The current caneberry subgroup 13A tolerance at 0.1 ppm should be replaced with a 

tolerance for the caneberry subgroup 13-07A. HED recommends that the tolerance level 

for the crop group be reduced as noted above to 0.05 ppm. 

 The current bushberry subgroup 13B tolerance at 40 ppm should be replaced with 

bushberry subgroup 13-07B tolerance at 40 ppm.

 The current citrus fruit group 10 tolerance of 5.0 ppm should be replaced with a citrus 

fruit group 10-10 tolerance. HED has no objection to raising the tolerance from its 

current level of 5.0 ppm to 9 ppm to harmonize with the Canadian MRL. 

 The current pome fruit group 11 tolerance of 10 ppm should be replaced with a pome 

fruit group 11-10 tolerance at 10 ppm.

For all of the recommended crop subgroup/crop group updates, the representative commodities 

for the old groups/subgroups are the same as for the new groups/subgroups and the 

recommended tolerance level is the same or lower than previously established; therefore, no 

additional data are needed to make these changes. 
Page 9 of 36

DIETARY EXPOSURE AND RISK

The most recent dietary risk assessment was conducted to support Section 3 registration on 

turnips, succulent peas, citrus, green onions, and leeks (D278156, A. Acierto, 3/7/02). 

There have been no changes to the residue inputs for this assessment since the 2002 dietary risk 

assessment was conducted. All registered uses were included in the 2002 dietary risk assessment 

at tolerance level residues and the assessment assumed 100% crop treated. During registration 

review, HED is recommending that several tolerances be lowered to allow for harmonization 

with Canadian MRLs. As noted above, HED is also recommending that the crop group tolerance 

for citrus fruit be increased from 5 ppm to 9 ppm. However, this increase is administrative in 

nature and is recommended only for purposes of tolerance harmonization. It is not as a result of 

an expected increase in residues above the previously established tolerance level which was the 

input value used in the 2002 dietary risk assessment. 

The 2002 dietary risk assessment used the Dietary Exposure Evaluation Model DEEM-FCIDTM 

software version 7.73, which incorporates consumption data from USDA’s Continuing Surveys 

of Food Intake by Individuals (CSFII), 1989-1992. HED is currently using the Dietary Exposure 

Evaluation Model software with the Food Commodity Intake Database (DEEM-FCID) Version 

3.16. This is effectively the same software as used in the previous dietary assessment; however 

it uses 2003-2008 food consumption data from the U.S. Department of Agriculture’s (USDA’s) 

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

(NHANES/WWEIA). HED has conducted evaluations to compare estimated risks using the two 

different consumption databases and results are generally comparable. Given the conservative 

inputs into the 2002 dietary risk assessment, the low risk estimates, and the low expected impact 

on overall results of the new consumption information, HED believes the previously conducted 

dietary risk assessment is adequate to address dietary risks under registration review. 

Food Exposure

The inputs into the 2002 dietary assessment and findings from that assessment are briefly 

summarized here. There is no hazard associated with acute exposure to fosetyl-Al; therefore 

only chronic dietary exposure is assessed for this active ingredient. A highly conservative 

chronic dietary exposure assessment was conducted using tolerance level residues, default 

processing factors, and 100% crop treated for all commodities. At the time of the last dietary 

assessment, it was HED policy that drinking water could not be directly incorporated into dietary 

assessments; therefore, the assessment includes food residues only. Dietary (food only) 

estimated exposure for the U.S. population was 0.089 mg/kg/day, which is equivalent to an 

estimated risk of 4% of the chronic Population Adjusted Dose (cPAD). The estimated exposure 

of 0.19 mg/kg/day for children 1-6, the most highly exposed population subgroup, is equivalent 

to an estimated risk of 8% of the cPAD. 

Drinking Water Exposure

EFED has determined that an updated drinking water assessment is not required to support the 

registration review of fosetyl-Al (email from J. Lin, EFED to D. Davis, HED dated 9/23/13). 

There are no monitoring data for fosetyl-Al; therefore, EFED provided modeled surface and 

groundwater estimated drinking water values. (ID# 0E06090, T. Steeger and J. Breithaupt, 
Page 10 of 36

6/8/01). Environmental fate properties suggest that fosetyl-Al is not likely to reach ground or 

surface water under most conditions, and if it does reach surface water, it is expected to degrade 

rapidly. EFED noted that if fosetyl-Al reached groundwater, it could persist. The Screening 

Concentration in Ground Water (SCI-GROW2) model estimated a concentration of less than 

0.006 parts per billion (ppb) in groundwater. 

At the time of the 2001 risk assessment, HED policy dictated the calculation of “drinking water 

levels of concern” (DWLOCs) be used as a tool to assess potential risk from drinking water. 

HED calculated DWLOCs for adults, young children (1-6 years old) and infants (<1 year old). 

The DWLOC calculation looked at the risk cup for the chemical, subtracted food exposure and 

residential exposure, assumed a standard water consumption value and provided a “target” water 

value. If the estimated drinking water concentration was below the DWLOC, there were no risks 

of concern. The DWLOCs were 102,000 ppb for adults, 25,000 ppb for children 1-6 years old, 

and 25,000 for infants. It is HED’s current policy is to directly input the modeled estimated 

drinking water concentrations into the dietary risk assessment which allows comparison with 

actual consumption data from the WWEIA survey. While differences do exist between the 

standard consumption values used to calculate the DWLOCs and the current consumption 

information used to calculate drinking water estimated dietary risks, the estimated drinking water 

concentration is orders of magnitude below exposure levels that might cause a concern ; 

therefore, HED concludes that there is no concern for risks associated with drinking water 

exposure. Further, directly incorporating modeled ground water estimated concentration of

0.006 ppb into the dietary risk assessment would not result in a risk of concern.

Conclusions

HED concludes that there are no dietary (food and water) drinking water risks associated with 

the registered uses of fosetyl-Al.

RESIDENTIAL EXPOSURE AND RISK 

The most recent residential exposure assessment was conducted to support Section 3 registration 

on turnips, succulent peas, citrus, green onions, and leeks (D279163, M. Clock-Rust, 5/17/01).

There have been no substantive changes to the residential turf application rate or registered use 

pattern since that assessment. However, subsequent to that assessment substantial changes have 

occurred regarding the exposure methodology HED uses to conduct residential assessments; 

therefore, HED has reassessed residential handler and post-application exposure to support 

registration review and to account for the 2012 Residential Standard Operating Procedures (SOP)

revision. 

Residential (Non-Occupational) Exposure/Risk Characterization

Fosetyl-Al is registered for a variety of uses, including some use patterns that are relevant for 

residential exposure assessment. Fosetyl-Al is registered for use on ornamental plants in 

residential areas, and is registered for use on turf grass on golf courses, and commercial turf 

areas where residential post-application exposure may occur. For residential handlers, exposure 

via the inhalation and dermal routes are anticipated, although no hazard has been identified for 

the dermal route of exposure. Therefore, only inhalation exposure has been quantitatively 
Page 11 of 36

assessed for residential handlers. Exposure durations consistent with short- and intermediateterm exposure were assessed. For residential post-application exposure, HED typically assesses 

adult dermal exposure and incidental oral exposure for children (1 < 2 years old). Since no 

hazard has been identified for the dermal route of exposure for fosetyl-al, quantitative 

assessment for only children’s incidental oral exposure was conducted. In the case of fosetyl-al, 

no chemical specific transfer data is available, so default values for transferable turf residues 

(TTR) are used to assess residential post-application exposure. 

Residential Handler Exposure

Based on the registered use patterns, short-term inhalation exposure has been quantitatively 

assessed for residential handler exposure scenarios (i.e., application to lawns/turf and ornamental 

gardens) using handheld application equipment. The residential handler exposure assessment 

reflects a range of application rates depending on the use pattern; the maximum application rate 

for fosetyl-Al is up to 17.6 lbs ai/A for turf applications. The residential handler exposure and 

risk assessment findings are summarized in Table 3. Inhalation margins of exposure (MOEs) 

ranged from 120,000 to 7,100,000. Risk estimates exceed the level of concern (LOC) of 100; 

therefore no risks of concern are identified for residential handlers as a result of the registered 

uses of fosetyl-Al. 

Table 3: Short-Term Residential Handler Exposure and Risk Estimates for Fosetyl-Al

Exposure Scenario Target 

MOE Inhalation Unit Exposure

Maximum 

Application 

Rate a

Amount 

Treated 

or 

Handled 

Daily b

Inhalation

Dose c MOE d

Mixer/Loader/Applicator

Gardens/Trees

[ornamentals/spottreatment lawn/turf]

Manually Pressurized 

Handwand

100 0.018 0.04 lb 

ai/gallon 0.000045 6,700,000

Gardens/Trees

[ornamentals/spottreatment lawn/turf]

Hose-End Sprayer

100 0.0014 0.002 lb ai/ft2 0.000042 7,100,000

Lawn/turf

[liquid concentrate]

Hose-end sprayer

100 0.022 17.6 lb ai/A 0.0024 120,000

Gardens/Trees

Ready-to-use

Hose-end sprayer

100 0.034 0.004 lb ai/ft2

0.001 150,000

a. Based on registered or existing product labels (D279163, Succulent

Peas, Citrus Fruit Group (10), Leeks, Green Onions, and the Bushberry Subgroup (13B), Mary Rust et al,

05/17/2001)

b. Exposure Science Advisory Council Policy #9.1

c. Inhalation Dose = Inhalation Unit Exposure (mg/kg) x Application Rate (lb ai/acre or gal) x Amount

Treated or Handled (A or gallons/day) /BW (80 kg)

d. Inhalation MOE = Inhalation NOAEL (mg/kg/day)/ Inhalation Dose (mg/kg/day)
Page 12 of 36

Residential Post-Application Exposure

Post-application exposure and risk estimates were assessed using the maximum turf application 

rate of 17.6 lbs ai/A. The exposure and risk estimates presented below (Table 4) represent shortterm incidental oral exposure (children 1 < 2 years old) to treated turf based on the 2012 

Residential SOPs. In the case of fosetyl-Al, only incidental oral exposure is quantitatively 

assessed because no dermal hazard was identified. Inhalation exposure is not quantitatively 

assessed for fosetyl-al because the combination of low vapor pressure for fosetyl-Al and dilution 

in outdoor air is likely to result in minimal inhalation exposure.

Chemical-specific transferable turf residue (TTR) data are not available for use in exposure 

assessment, so default TTR values included in the 2012 Residential SOP revision were used to 

assess residential post application exposure and risk. 

The residential post application exposure and risk assessment findings are summarized in Table 

4. The MOEs for children 1 < 2 years old ranged from 1,100 to 500,000. MOEs exceed the 

LOC of 100; therefore no risks of concern are identified for residential post-application as a 

result of the registered uses of fosetyl-Al. 

Table 4: Short-term Residential Post Application Exposure and Risk Estimates for fosetyl-Al

Lifestage Post Application Exposure Scenario Dose (mg/kg/day) MOEs

Children 1 < 2 

years old Lawn/turf sprays

Hand to Mouth 0.268 1,100

Object to Mouth 0.008 37,000

Incidental Soil Ingestion 6.0E-04 500,000

Combined Residential Exposure

Recommendations for aggregate risk assessment are shown in Table 5. 

 The recommended residential exposure for use in the adult aggregate assessment reflects 

inhalation exposure from the hose end sprayer for turf applications. 

 The recommended residential exposure for use in the children 1 to 2 years old aggregate 

assessment reflects incidental exposure from post-application exposure to treated turf.

1 Residential Handler Dose = the highest handler dose for each applicable lifestage of all residential handler scenarios assessed. Total = 

dermal + inhalation (where applicable).

2 Residential Handler MOE = the MOEs associated with the highest residential handler doses. Total = 1 ÷ (1/Dermal MOE) + 

(1/Inhalation MOE) [if both exposure routes are applicable].

3 Residential Post-application Dose = the highest post-application dose for each applicable lifestage of all post-application scenarios 

assessed. Total = dermal + inhalation + incidental oral (where applicable).

4 Residential Post-application MOE = the MOEs associated with the highest post-application doses. Total = Dermal MOE + Inhalation 

MOE + Incidental Oral MOE (where applicable). 

Table 5: Short- and Intermediate-Term Residential Exposures for the fosetyl-Al Combined Residential Risk 

Calculations

Population

Handler Exposure 

(mg/kg/day)1

Residential

Handler Total 

Exposure 

(mg/kg/day)2

Postapplication Exposure 

(mg/kg/day)3

Residential 

Postapplication 

Total Exposure 

(mg/kg/day) Dermal Inhalation Dermal Inhalation Oral 4

Short-Term

Adult Male N/A 0.0024 0.0024 N/A N/A N/A N/A

Adult Female N/A 0.0024 0.0024 N/A N/A N/A N/A

Children 1 to < 2 

years old N/A N/A N/A N/A N/A 0.268 0.268
Page 13 of 36

Residential Bystander Post Application Inhalation Exposure

Based on the Agency's current practices, a quantitative post-application inhalation exposure 

assessment was not performed for fosetyl-Al at this time primarily because of the low acute 

inhalation toxicity (Toxicity Category III and IV) and low vapor pressure (0.013 mPa at 25°C).

However, volatilization of pesticides may be a source of post-application inhalation exposure to 

individuals nearby pesticide applications. The Agency sought expert advice and input on issues 

related to volatilization of pesticides from its Federal Insecticide, Fungicide, and Rodenticide Act 

Scientific Advisory Panel (SAP) in December 2009, and received the SAP’s final report on 

March 2, 2010 (http://www.epa.gov/scipoly/sap/meetings/2009/120109meeting.html). The 

Agency is in the process of evaluating the SAP report and may, as appropriate, develop policies 

and procedures to identify the need for and, subsequently, the way to incorporate postapplication inhalation exposure into the Agency's risk assessments. If new policies or 

procedures are developed, the Agency may revisit the need for a quantitative post-application 

inhalation exposure assessment for fosetyl-Al.

Spray Drift

Off-target movement of pesticides can occur via many types of pathways and it is governed by a 

variety of factors. Sprays that are released and do not deposit in the application area end up offtarget and can lead to exposures to those it may directly contact. They can also deposit on 

surfaces where contact with residues can eventually lead to exposures (e.g., children playing on 

lawns where residues have deposited next to treated fields). The potential risk estimates from 

these residues can be calculated using drift modeling coupled with methods employed for 

residential risk assessments for turf products.

The approach to be used for quantitatively incorporating spray drift into risk assessment include 

assessing exposures for children (1 to 2 years old) and adults who have contact with turf where 

residues are assumed to have deposited via spray drift thus resulting in an exposure scenario. 

Aside from the predicted residues available for transfer, the routes of exposure and assessment 

methodology are analogous to how exposures to turf products are considered in risk assessment. 

Several fosetyl-Al products have existing labels for use on turf, thus it was considered whether 

the risk assessment for turf may be considered protective of any type of exposure resulting from 

spray drift. If the maximum application rate on crops adjusted by the amount of drift expected is 

less than or equal to existing turf application rates, the existing turf assessment is considered 

protective of spray drift exposure. The proposed maximum single application rate of fosetyl-Al

for turf is 17.6 lbs ai/A. The highest fraction of spray drift noted for any application method 

immediately adjacent to a treated field results in a deposition fraction of 0.261of the application 

rate. A quantitative spray drift assessment for fosetyl-Al is not required because the maximum 

application rate for a crop/target site multiplied by the adjustment factor for drift of 0.26 is less 

than the maximum direct spray residential turf application rate of 17.6 lb ai/A for any fosetyl-Al

products. The turf post-application MOEs are protective for any potential exposures related to 

spray drift for fosetyl-Al and have previously been discussed above. 

 

1 Tier 1 output from the aerial application using fine to medium spray quality based on AgDrift output files
Page 14 of 36

AGGREGATE EXPOSURE AND RISK

No aggregate risk issues were identified in the most recent human health risk assessment cited 

above. As previously noted, food and water exposures have not changed substantially from the 

prior dietary exposure assessment. The residential risk assessment has also not changed 

substantially. Adult residential exposure was 0.0021 mg/kg/day in the 2001 assessment, and has 

been updated to 0.0024 mg/kg/day. Residential exposure to children has been decreased from 

2001 where it was 0.34 ppm, and has been reassessed to be 0.27 mg/kg/day. In 2001 aggregate 

risks were conducted by using the appropriate POD and the LOC to calculate the maximum 

allowable exposure in mg/kg/day. The dietary (food only) and residential exposure were 

subtracted from that maximum, and the remaining exposure was allocated to water and a 

DWLOC was calculated. If the estimated drinking water concentrations were below the 

DWLOCs, then the maximum allowed exposure was not exceeded and there were no aggregate 

risks of concern. While this aggregate methodology varies from the current practice of directly 

including water in the dietary risk assessment, and combining dietary (food and water) with 

residential and comparing to the appropriate NOAEL, the 2001 assessment is acceptable for the 

purposes of registration review as it clearly demonstrates that there will be no aggregate risks of 

concern for fosetyl-Al. As noted above, the calculated DWLOCs were 102,000 ppb for adults 

and 25,000 for children. The drinking water estimated concentration of 0.006 ppb is 

substantially below those DWLOCs. Even though there have been some slight changes in 

exposure values, all the assessments included in the 2001 human health risk assessment use 

conservative, health protective inputs, and are likely to have over-estimated risk. Even with 

small changes, there will be no risks of concern identified if a quantitative update of the 

aggregate risk were completed. HED considers the current information sufficient to demonstrate 

that there are no aggregate risks associated with the registered uses of fosetyl-Al.

OCCUPATIONAL EXPOSURE AND RISK (Agricultural Crops)

The most recent occupational exposure assessment was conducted to support Section 3 

registration on turnips, succulent peas, citrus, green onions, and leeks (D279163, M. Clock-Rust, 

5/17/01). Additionally, HED assessed occupational exposure to fosetyl-al in 2 separate actions 

in 2005; 1) Occupational Risk Assessment to Support Request for a Section 3 Registration of 

Fosetyl-Al on Tobacco, D317831. B. O’Keefe, 7/1/2005.; and 2) Fosetyl-Al (Aliette® WDG 

Fungicide). Proposed Label Amendment to Reduce REI, D313651 & D315276. B. O’Keefe, 

7/1/2005.

Although there have not been substantive use pattern changes since the above exposure and risk 

assessments, HED has reassessed occupational handler and post application exposure to support 

registration review and to account for updated unit exposure data. EPA has updated the 

occupational inhalation risk assessment for fosetyl-Al to reflect current HED policy and 

available unit exposure data, registered use pattern information, appropriate exposure duration 

(short- and intermediate-term), and endpoint selection. No risk is expected via the dermal route 

of exposure because no hazard was observed [based on the lack of systemic effects following 

repeat dermal exposure of rabbits at dose levels up to 1500 mg/kg/day, which is greater than the

limit dose]. 
Page 15 of 36

Fosetyl-Al is registered for ground/airblast application on a wide variety of agricultural crops 

(see Residue Chemistry section for additional information). 

Commercial applicators may also be exposed to fosetyl-Al due to the registered use pattern on 

ornamental plants in residential areas, turf grass on golf courses, sod farms, and other 

commercial turf areas. Rates range from 6.6 to 8.7 pounds ai/acre with an application interval of 

14 days and 13.3 to 17.4 pounds ai/acre with an application interval of 21 days. There is potential 

for short- and intermediate-term occupational exposure to fosetyl-Al during handling (mixing, 

loading, applying) of liquid and wettable powder formulations with airblast equipment.

Personal Protective Equipment (PPE) for fosetyl-Al product includes chemical-resistant gloves 

and eye protection because it is a severe eye irritant. Available product labels indicate applicators 

should wear goggles or a face shield.

Short-/Intermediate Occupational Handler Risk

Table 6 shows the calculated short- and intermediate-term risk estimates for occupational 

inhalation exposure based on the registered use pattern and formulations of fosetyl-Al. No risk 

estimates of concern (i.e., MOEs<100) were identified.

Fosetyl-Al is also registered as an injectable fungicide (EPA Reg. No: 264-504; bark injection of 

citrus trees). At this time, HED does not have appropriate unit exposure values to represent the 

tree injection exposure scenario; however, HED believes that the occupational exposure from the 

tree injection use is lower than those scenarios quantitatively assessed below given the label 

directions, label-specified personal protective equipment and agricultural practices.

Table 6. Baseline Short- and Intermediate-Term Occupational Exposures and Risk Estimates for Fosetyl-Al.

Exposure Scenario

Application 

Rate a

Area 

Treated 

Daily b

ST/IT

Baseline 

Inhalati

on UEs c

ST/IT

Baseline Inhalation 

Dose d

ST/IT

Baseline Inhalation 

MOE e

lb ai/A acres μg/lb ai mg/kg/day ST LOC = 100 

Mixer/Loader

Aerial Mixer/Loader

Dry Flowable/Water 

Dispersable Granule 

Formulation 

Orchard/field crop

4 350 8.96 0.156 1,900

Aerial Mixer/Loader

Dry Flowable/Water 

Dispersable Granules 

Formulation 

nursery

4 60 8.96 0.0269 11,000

Aerial Mixer/Loader

Wettable Powders

nursery

4 60 43 0.129 2,300

Aerial Mixer/Loader

liquid formulations

Orchard/field crop

4 350 0.219 0.00384 78,000

Aerial Mixer/Loader

liquid formulations

nursery

4 60 0.219 0.000658 460,000
Page 16 of 36

Table 6. Baseline Short- and Intermediate-Term Occupational Exposures and Risk Estimates for Fosetyl-Al.

Exposure Scenario

Application 

Rate a

Area 

Treated 

Daily b

ST/IT

Baseline 

Inhalati

on UEs c

ST/IT

Baseline Inhalation 

Dose d

ST/IT

Baseline Inhalation 

MOE e

lb ai/A acres μg/lb ai mg/kg/day ST LOC = 100 

Airblast Mixer/Loader

Dry Flowable/Water 

Dispersable Granule 

Formulation 

orchard

6 40 8.96 0.0269 11,000

Airblast Mixer/Loader

Dry Flowable/Water 

Dispersable Granule 

Formulation 

nursery

4 20 8.96 0.00896 33,000

Groundboom 

Mixer/LoaderBroadcast –

golf course

17.6 40 0.34 0.00299 100,000

Groundboom 

Mixer/Loader

liquid formulations

Field crop, typical

4 80 0.219 0.000876 340,000

Groundboom 

Mixer/Loader

liquid formulations

nursery

4 60 0.219 0.000658 460,000

Flagger

Flagger

Field crop/orchard 4 350 0.35 0.00613 49,000

Applicator

Groundboom applicator

Liquid sprays 4 80 0.34 0.00136 220,000

Aerial applicator

nursery

(engineering controls)

4 60 0.0049 0.0000148 20,000,000

Aerial applicator

Field crop/orchard

(engineering controls)

4 350 0.0049 0.0000858 3,500,000

Applicator

Airblast

(macadamian nuts)

6 40 4.71 0.0141 21,000

Golf course (fairways, 

tees, greens) 17.6 40 4.71 0.00943 32,000

Golf course (tees and 

greens only) 17.6 5 4.71 0.000374 800,000

a Application Rates based on existing or registered uses for fosetyl-Al).

b Acres Treated Per Day is taken from Exposure Science Advisory Council (ExpoSAC) Policy No. 9.1.

c UEs = Unit Exposures based on PHED Version 1.1, ORETF, or AHETF data. Baseline = no gloves, no respirator.

d Dose (mg/kg/day) = daily unit exposure (μg/lb ai) × application rate (lb ai/acre) × amount handled/day (acres/day) x 

conversion factor (1 mg/1,000 μg) × absorption factor (%) ÷ body weight (80 kg). No inhalation absorption factor.

e MOE = NOAEL ÷ Dose (mg/kg/day). ST/IT Inhalation NOAEL = 100 mg/kg/day. ST/IT level of concern = 100. 
Page 17 of 36

Short- and Intermediate-Term Occupational Dermal Post-Application Risk

Post application exposure is possible for workers entering fosetyl-Al treated fields. A dermal 

occupational post application risk assessment was not performed, because fosetyl-Al does not 

pose a dermal hazard. 

Technical fosetyl-Al falls into Toxicity Category I for primary eye irritation. Per the Worker 

Protection Standard (WPS), a 48-hour REI is required for chemicals classified under Toxicity 

Category I. Therefore, the existing product labels should be reviewed for the appropriate REI for 

compliance with WPS. Existing product labels should be amended to reflect a 48-hour REI.

Inhalation Occupational Post Application Risk

Based on the Agency's current practices, a quantitative post-application inhalation exposure 

assessment was not performed for fosetyl-Al at this time primarily because of the low acute 

inhalation toxicity (Toxicity Category III and IV), and low vapor pressure (0.013 mPa at 25°C).

However, 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 Federal Insecticide, Fungicide, and Rodenticide Act Scientific Advisory 

Panel (SAP) in December 2009, and received the SAP’s final report on March 2, 2010 

(http://www.epa.gov/scipoly/sap/meetings/2009/120109meeting.html). The Agency is in the 

process of evaluating the SAP report as well as available post-application inhalation exposure 

data generated by the Agricultural Reentry Task Force and may, as appropriate, develop policies 

and procedures, to identify the need for and, subsequently, the way to incorporate occupational 

post-application inhalation exposure into the Agency's risk assessments. If new policies or 

procedures are put into place, the Agency may revisit the need for a quantitative occupational 

post-application inhalation exposure assessment for fosetyl-Al.

Although a quantitative occupational post application inhalation exposure assessment was not 

performed, an inhalation exposure assessment was performed for occupational/commercial 

handlers. Handler exposure resulting from application of pesticides outdoors is likely to result in 

higher exposure than post application exposure. Therefore, it is expected that these handler 

inhalation exposure estimates would be protective of most occupational post-application 

inhalation exposure scenarios.

As fosetyl-Al is registered for use on tree nuts (e.g. walnuts, almonds, etc.), inhalation exposure 

during dusty mechanical activities such as shaking and mechanical harvesting is another 

potential source of post-application inhalation exposure. However, the airblast applicator 

scenario (See Table 6) is believed to represent a reasonable worst case surrogate estimate of post

application inhalation exposure during these dusty mechanical harvesting activities. 

OCCUPATIONAL EXPOSURE AND RISK (Seed Treatment)

Besides for the agricultural and commercial turf applications addressed above, fosetyl-al is 

registered as a Special Local Need (SLN) in Idaho for use on succulent peas as a seed treatment. 

Occupational seed treatment handlers may experience short- and intermediate-term exposure to
Page 18 of 36

fosetyl-al while performing seed treatment activities in commercial settings. In addition, 

occupational secondary handlers may experience short- and intermediate-term exposure while 

planting fosetyl-al treated seeds. No chemical-specific handler exposure data were submitted in 

support of this use pattern. For assessing commercial seed treatment and seed planting activities, 

unit exposure data were taken from HED ExpoSAC Policy 14: SOPs for Seed Treatment. The 

amount of active ingredient handled depends on the application rate (lb ai/lb seed) and the 

pounds of seed treated in a day (or the pounds of seed that can be planted in a day), all of which 

vary depending upon the seed type. Values for the amount of seed treated and planted per day 

were obtained from HED ExpoSAC Policy 15.1. The results are presented in Tables 7 and 8. All 

the calculated risk estimates exceed an MOE of 28,000 (range: 28,000 – 390,000).

Treating Seed (Primary Handler)

Potential occupational exposure scenarios from the use of fosetyl-al as a commercial seed 

treatment include:

 Mixing, loading, applying liquid formulations;

 Bagging treated seed;

 Sewing bags; and

 Multiple activities.

Typically, for large-scale commercial seed treatments, workers perform only those specific 

individual tasks listed above; however, it is assumed that workers also may perform multiple 

activities throughout the day. As a result a “multiple activities” scenario (i.e. where one worker 

performs all seed treatment tasks such as loading/applying, sewing, bagging, cleaning, 

calibration, repair, forklift driver, etc.) was addressed.

Planting Treated Seed (Secondary Handler)

Potential occupational exposure scenarios from the use of fosetyl-al as a commercial seed 

treatment include planting treated seed (secondary handler).

Planting treated seed consists of the farmer purchasing bags of treated seed, placing the seed in 

the hopper and applying seed to fields (considered a secondary handler exposure scenario).

Exposure Data, Factors, and Assumptions

The following are exposure factors and assumptions used to calculate exposure and risk in the 

occupational assessment for commercial seed treatment scenarios. 

Unit Exposures

Chemical-specific data for assessing exposure during commercial seed treatment and seed 

planting were not submitted to the Agency in support of this risk assessment. In the absence of 

chemical-specific data, unit exposures are from ExpoSAC Policy 14: SOPs for Seed Treatment

(May 1, 2003). Unit exposure values from ExpoSAC Policy 14 are based on data for open 
Page 19 of 36

mixing/loading/application systems. HED SOP 15.1 provides guidance to exposure assessors on 

the amount of commercial seed treated per day.

Amount of Seed Treated Per Day (Primary Handler)

The amount of seed treated per day at a commercial facility is summarized below for the relevant 

exposure duration (short- and intermediate-term). 

 Dry beans and peas (for succulent pea) – 281,250 lbs (ST), and 200,000 lbs (IT)

Amount of Seed Planted Per Day (Secondary Handler)

HED has worked closely with OPP’s Biological and Economic Analysis Division (BEAD) to 

define the amount of seed planted per day. The appropriate value is shown below.

 Dry beans and peas (for succulent pea) – 16,000 lbs

Application Rates

The succulent pea seed treatment rate is 0.00019 lb ai/lb seed for seed treatment. 

Body Weight

The average adult weight of 80 kg was used for estimating inhalation exposure since the 

endpoint was based on not based on developmental effects.

Exposure Duration

It is anticipated that occupational fosetyl-al exposures will generally occur in short- (1-30 days) 

and intermediate- (1-6 months) term durations.

Absorption Factor

Since no inhalation absorption data are available, toxicity by the inhalation route is considered to 

be equivalent to the estimated toxicity by the oral route of exposure (100% absorption factor).

Seed Treatment Handler Exposure and Risk Summary 

Primary Handler

A summary of the inhalation risk estimates for the succulent pea seed treatment exposure 

scenario is presented in Table 7 for short-term and intermediate-term inhalation exposures. 

Dermal exposure and risk estimates are not calculated because no dermal hazard was identified.

The results of the occupational handler exposure and risk assessment indicate that inhalation risk

estimates are not of concern (MOEs ≥ 100) at baseline exposure. 

HED is currently in the process of revising ExpoSAC Policy 15 in efforts to update the daily 

amount of seed treated in commercial seed treatment facilities. With the increasing demand for 

hybridized treated seeds, there have been modifications not only in the seed treatment 
Page 20 of 36

equipment, but in the market shares of new and currently registered pesticide products. HED 

understands that due to the high cost of producing hybrid seeds, direct seeding is done in a 

precision manner which requires lower volumes of seed per acre. However, this does not 

provide a direct correlation to the amount of seed which is treated in the commercial seed 

treatment facilities. 

Seed Treatment Occupational Post-Application Exposures and Risks 

The potential for post-application exposures following the planting of fosetyl al treated seeds is 

unlikely because sustained levels of contact with treated seed after it has been placed in the soil 

or other planting media would not be expected because no routine cultural practice required for 

the production of agricultural commodities involves such an activity as defined in the no/low 

contact criteria in the Worker Protection Standard (WPS). Therefore, no quantitative postapplication assessment is required for exposure to treated seeds that have already been planted.

The labeling should state: Seed that has been treated with this product that is then packaged or 

bagged for future use must contain the following labeling on the outside of the seed package or 

bag. 

"Treated Seed - Do Not Use for Food, Feed, or Oil Purposes.

When opening this bag or loading/pouring the treated seed, wear a long-sleeved 

shirt, long pants, shoes, socks, and chemical resistant gloves. After the seeds have 

been planted, do not enter or allow worker entry into treated areas during the 

restricted-entry interval (REI) of 48 hours. Exception: Once the seeds are planted 

in soil or other planting media, the Worker Protection Standard allows workers to 

enter the treated area without restriction if there will be no worker contact with 

the treated seeds in the soil or planting media."

Table 7. Summary of Short- and Intermediate-Term Handler Exposures and Risks for 

Fosetyl al (Seed Treatment Only).

Seed Type

Dermal 

UEa

Inhal 

UEa

Max App 

Rateb

Amt 

Treatedc

Inhal

Dosed

Inhal

MOEe

mg/lb mg/lb lb ai/lb seed lb seed/day mg/kg/day LOC = 100

LOADER/APPLICATOR (single layer, gloves)

Succulent 

Peas (ST) N/A

0.00034 0.00019

281,250 0.0023 170,000

Succulent 

Peas (IT) N/A 200,000 0.0016 280,000

SEWER (single layer, NO gloves)

Succulent 

Peas (ST) N/A

0.00023 0.00019

281,250 0.0015 200,000

Succulent 

Peas (IT) N/A 200,000 0.00086 350,000
Page 21 of 36

Table 7. Summary of Short- and Intermediate-Term Handler Exposures and Risks for 

Fosetyl al (Seed Treatment Only).

Seed Type

Dermal 

UEa

Inhal 

UEa

Max App 

Rateb

Amt 

Treatedc

Inhal

Dosed

Inhal

MOEe

mg/lb mg/lb lb ai/lb seed lb seed/day mg/kg/day LOC = 100

BAGGER (single layer, NO gloves)

Succulent 

Peas (ST) N/A

0.00016 0.00019

281,250 0.0011 280,000

Succulent 

Peas (IT) N/A 200,000 0.0008 390,000

MULTIPLE ACTIVITIES (combination of loader/applicator with gloves + no coveralls, 

sewer without gloves, stacker without gloves)

Succulent 

Peas (ST) N/A

0.0016 0.00019 281,250 0.011 28,000

Succulent 

Peas (IT) N/A 200,000 0.008 39,000

a Unit Exposures from HED Exposure Science Advisory Council Policy 14 (baseline inhalation = no respirator).

b Application Rates based on proposed label uses for fosetyl al.

c HED default for lb seed treated per day from HED Exposure Science Advisory Council Policy 15.

d Daily Inhalation Dose (mg/kg/day) = daily inhalation unit exposure (mg/lb ai) x application rate (lb ai/lb seed) x amount planted (lb seed/day) 

x absorption factor (100%) / body weight (80 kg adult).

e Inhalation MOE = NOAEL (300 mg/kg/day for short- and intermediate-term exposure) / Inhalation Dose (mg/kg/day). Level of concern = 100.

Table 8. Summary of Secondary Handler (Planter) Exposures and Risks for Fosetyl al (Single 

Layer, Gloves for Loading Only).

Seed Type

Dermal 

UEa

Inhal 

UEa

Max App 

Rateb

Amt of Seed 

Planted/Dayc

Inhalation

Dosed

Inhalation

MOEe

mg/lb mg/lb lb ai/lb 

seed lb seed/day mg/kg/day LOC = 100

Beans and Peas N/A 0.0034 0.00019 16,000 0.001 230,000

a Unit Exposures from HED Exposure Science Advisory Council Policy 14: Standard Operating Procedures for Seed Treatment. 

b Application Rates based on proposed label uses for fosetyl-al.

c HED default for lb seed planted per day from HED Exposure Science Advisory Council Policy 15.1.

d Daily Inhalation Dose (mg/kg/day) = daily inhalation unit exposure (mg/lb ai) x application rate (lb ai/lb seed) x amount planted (lb seed/day) 

x absorption factor (100%) / body weight (80 kg adult).

e Inhalation MOE = NOAEL (300 mg/kg/day for short- and intermediate-term exposure) / Inhalation Dose (mg/kg/day). Level of concern = 100.
Page 22 of 36

Appendix A. Toxicity Information

Table A.1 Acute Toxicity Profile – Fosetyl-Al

Guideline 

No. Study Type MRID Guideline No. Guideline No.

870.1100 Acute oral [rat] 00247160 LD50 > 5000 mg/kg IV

870.1200 Acute dermal [rat] 00247160 LD50 > 3000 mg/kg III

870.1300 Acute inhalation [rat] 00247160 LC50 > 1.73 mg/L III

870.2400 Acute eye irritation [rabbit] 00247160 Severe eye irritant I

870.2500 Acute dermal irritation [rabbit] 00247160 not an irritant IV

870.2600 Skin sensitization [guinea pig] 00247160 not a dermal sensitizer N/A

Table A.2 Subchronic, Chronic and Other Toxicity Profile – Fosetyl-Al

Guideline No./ 

Study Type

MRID No. (year)

Classification /Doses

Results

No guideline

4-week study

MRID 00098341 (1981)

0, 10000, 20000, 40000 ppm

acceptable/non-guideline

TXR0004140

mechanistic study; determination of calcium and 

phosphorus in the serum, urine and feces; fosetyl-Al

induced alterations of the calcium/phosphorus 

excretion, as evidenced by a dose related increased 

calciuria in both sexes, a slight decrease in urinary 

excretion of phosphorus at all dose levels, a 

questionable increase in fecal calcium excretion in 

high-dose males, a significant increase in fecal 

phosphorus excretion in mid- and high-dose males. 

Histological examination showed mild dose related 

alterations of the epithelial cells of the renal tubules. 

870.3100

90-Day oral 

toxicity [SpragueDawley Crl:CD® 

(SD) BR rat]

MRID 41315201 (1989)

0, 8000, 30000, 50000 ppm

Males 0, 500, 2100, 3500 mg/kg/day

Females 0, 600, 2500, 4200 

mg/kg/day

Acceptable/non-guideline

TXR#0008207

NOAEL = 500 mg/kg/day

LOAEL = 2100 mg/kg/day, based on 

histopathological changes in urinary bladder seen in 

2-year study related to calculi formation in bladder

[calculi in kidneys, ureters, urinary bladder; calculi 

formation nearly always associated with transitional 

cell hyperplasia in kidneys, ureters, and bladder]

870.3150

13-week oral 

toxicity in 

nonrodent [dog]

MRID 00098337 (1977)

0, 2000, 10000, 50000 ppm

Males 0, 58, 274, 1309 mg/kg/day

Females 0, 58, 272, 1446 mg/lg/day

acceptable/guideline

NOAEL = 10000 ppm [274/272 mg/kg/day]

LOAEL = 50000 ppm [1309/1446 mg/kg/day], based 

on decreased serum potassium but no histopathological 

changes.

870.3200

21-Day dermal 

toxicity (rabbit)

MRID 00098338 (1979)

0, 380, 750, 1500 mg/kg/day

acceptable/guideline

NOAEL (systemic) = 1500 mg/kg/day

LOAEL (systemic) >1500 mg/kg/day (HDT)

870.3465 

90-day inhalation 

toxicity

Study requirement waived HASPOC memo TXR No. 0056809, dated 10/29/13
Page 23 of 36

Table A.2 Subchronic, Chronic and Other Toxicity Profile – Fosetyl-Al

Guideline No./ 

Study Type

MRID No. (year)

Classification /Doses

Results

870.3700a

Prenatal 

developmental in 

rodent (CFY 

strain SPF rat)

MRID 00114091 (1977)

MRID 00247174 ()

0, 500, 100, or 4000 mg/kg/day

GD 6-15

acceptable/guideline

Maternal toxicity NOAEL = 1000 mg/kg/day 

Maternal toxicity LOAEL = 4000 mg/kg/day, based 

on mortality, decreased body weight gain, and an 

increase in total resorptions

Developmental toxicity NOAEL = 1000 mg/kg/day

Developmental toxicity LOAEL = 4000 mg/kg/day, 

based on decreased litter size and fetal body weight, 

increased incidence of fetal malformations and 

skeletal variations, and an increase in total 

resorptions.

870.3700b

Prenatal 

developmental in 

nonrodent (New 

Zealand White 

Ju/RPrabbit)

MRID 00098347 (1976)

MRID 00247174

0, 125, 250, or 500 mg/kg/day

GD 6-16

acceptable/guideline 

Maternal toxicity NOAEL = 125 mg/kg/day 

Maternal toxicity LOAEL = 250 mg/kg/day, based 

on decreased body weight gain;

at 500 mg/kg/day, similar findings 

Developmental toxicity NOAEL > 500 mg/kg/day 

Developmental toxicity LOAEL not identified

870.3800

Reproduction and 

fertility effects 

(CFY strain SPF 

rats)

MRID 00098348/00114091 

(1982/1977)

0, 6000, 12000, 24000 ppm

0, 300, 600, 1200 mg/kg/day (std 

conversion)

acceptable/guideline 

Parental toxicity NOAEL = 6000 ppm (300

mg/kg/day)

Parental toxicity LOAEL = 12000 ppm [600 

mg/kg/day], based on decreased body weight gains 

of F2b generation and urinary tract changes in adults

Reproductive NOAEL = 24000 ppm [1200 

mg/kg/day (HDT)]

Offspring NOAEL = 6000 ppm [300 mg/kg/day] 

Offspring LOAEL = 12000 ppm [600 mg/kg/day, 

based on reduced litter and pup body weights in both 

matings of each generation

At 24000 ppm [1200 mg/kg/day], retarded body 

weight gain and lower litter and mean pup body 

weight in mid and late lactation; increased incidence 

of pathological changes in urinary bladder (F1b/F2b)

870.4100a

Chronic toxicity 

rodents (Charles 

River CD-1 rat)

See below under 870.4200

870.4100b

Chronic toxicity 

nonrodent (dog)

MRID 00098340 (1981)

0, 10000, 20000, or 40000 ppm (0, 

250, 500, 1000 mg/kg/day)

acceptable/guideline

NOAEL = 10000 ppm [250 mg/kg/day]

LOAEL = 20000 ppm [500 mg/kg/day], based on 

testicular degeneration (spermatocyte and/or 

spermatidic giant cells in the lumen of the 

seminiferous tubules); similar findings at 1000 

mg/kg/day

870.4200

Carcinogenicity 

mice (Charles 

River CD-1 

mouse)

MRID 00098353 (1981)

MRID 00247168 

0, 2500, 10000, 20000/30000 ppm

0, 357, 1429, or 2857/4286 

mg/kg/day for 24 months

acceptable/guideline

NOAEL = 30000 ppm (4286 mg/kg/day)

LOAEL was not determined

No compound-related effects on survival, body 

weight, histopathology other than hematology 

findings (↓segmented neutrophils, ↑ lymphocytes, 

↓reticulocyte counts. 

No evidence of tumors.
Page 24 of 36

Table A.2 Subchronic, Chronic and Other Toxicity Profile – Fosetyl-Al

Guideline No./ 

Study Type

MRID No. (year)

Classification /Doses

Results

870.4300

Combined 

chronic toxicity/

carcinogenicity 

(Charles River 

CD-1 rat)

MRID 00098339/00098352 (1982)

MRID 00247162-166 (1981)

0, 2000, 8000, or 40000/30000 ppm

0, 100, 400, 1500 mg/kg/day (std 

conversion) for 24 months

acceptable/guideline

NOAEL = 8000 ppm (400 mg/kg/day)

LOAEL = 40000/30000 ppm (1500 mg/kg/day), 

based on an increase in protein (urinalysis), and 

transitional epithelial cell tumors (adenomas/ 

carcinomas) in the urinary bladder

NOTE: Tumors considered likely due to prolonged 

mechanical irritation by bladder calculi, which 

appear to be present as a result of the calciumphosphorus imbalance at high doses (in excess of the 

limit dose).

870.5100

Gene Mutation -

Ames assay

MRID 00098342 (1977)

MRID 00247173 (1977)

Salmonella typhimurium

TA1535, TA1537, TA98, TA100

1, 10, 100, 1000 μg/plate and 125, 

250, 500, 1000 μg/plate without S9

125, 250, 500, 1000 μg/plate with 

S9; Spot test at 5 μg/disc (+S9/-S9)

Acceptable/guideline

Not mutagenic in the battery of Salmonella 

typhimurium strains when tested in the Ames 

procedure with and without S9 or in the spot test.

870.5100

Gene Mutation -

Ames assay

MRID 00098343 (1981)

Salmonella typhimurium (TA1535, 

TA1537, TA1538, TA98, TA100) 

125, 250, 500, 1000 μg/plate ±S9

Acceptable/guideline

No mutagenic activity in the basic battery of 

Salmonella typhimurium strains treated up to 

precipitation (with and without S9)

870.5385

Micronucleus 

assay

Swiss mouse

MRID 00098344 (1977)

MRID 00247173 (1977)

1000, 2000, 4000 mg/kg

(fosetyl-Al and hydrated 

monosodium phosphite)

Acceptable/guideline

Fosetyl-Al and hydrated monosodium phosphite 

were neither clastogenic nor aneugenic up to lethal 

doses (fosetyl-Al) or at doses > limit dose 

(metabolite); no increase in frequency of micronuclei 

in polychromatic erythrocytes at 1000 and 2000 

mg/kg fosetyl or 1000, 2000, 4000 mg/kg phosphite 

metabolite. All mice at 4000 mg fosetyl Al/kg died.

870.5385

Micronucleus 

assay 

CD-1 mouse

MRID 00098345

MRID 00247186 (1981)

CD-1 mice

600, 1200, 2400, 3600 mg/kg

1 dose (bone marrow collected at 30 

hours); 2 doses (collected at 48 

hours)

Acceptable/guideline

No increase in the incidence of micronuclei in 

polychromatic erythrocytes (MPCE) up to lethal 

doses

870.5550

DNA repair test –

MRID 00247173 (1981)

-S9: 12.5, 25, 50, 100 μg/plate

+S9: 6.25, 12.5, 25, 50, 100 μg/plate

Negative with and without S9

870.5550

DNA repair test –

E. coli

MRID 00247186 (1981)

62.5, 125, 250, 500, μg/plate

Acceptable

Negative at concentrations up to 500 μg/plate 

without S9
Page 25 of 36

Table A.2 Subchronic, Chronic and Other Toxicity Profile – Fosetyl-Al

Guideline No./ 

Study Type

MRID No. (year)

Classification /Doses

Results

Phage induction 

test

MRID 00098346 (1978)

0.05, 0.1, 0.5, 1, 5, 10, 50, 100, 500, 

1000 μg/mL. Escherichia coli K12 

harboring lambda prophage was 

utilized for the assay: Strain 

GY4015 was used as an indicator 

strain; GY5027 (lysogenic for 

lambda papa) was used to measure 

inducer activity; and strain GY5029 

(lysogenic for lambda c1857) was 

used to measure toxicity to phage 

development.

Unacceptable/non-guideline

Fosetyl-Al inhibited phage development in the 

I.P.L.M. (preincubation) test with strain GY5029 at 

50 μg/plate without metabolic activation (-S9), but 

no inhibition occurred at the same concentration in 

the presence of activation (+S9). The same effect 

was produced in the P.I. (plate) test with strain 

GY5027, confirming detoxication by S9. No 

inducing activity was detected

Phage induction 

test

MRID 00098346 (1978)

MRID 00247173 (1978)

1, 5, 10, 50, 100, 500, 1000, and 

2000 μg. Escherichia coli K12 

harboring lambda prophage was 

utilized for the assay: Strain 

GY4015 was used as an indicator 

strain; GY5027 (lysogenic for 

lambda papa) was used to measure 

inducer activity; and strain GY5029 

(lysogenic for lambda c1857) was 

used to measure toxicity to phage 

development.

Acceptable

Fosetyl-Al inhibited phage development in the 

I.P.L.M. (preincubation) test with strain GY5029 at 

50 μg/plate without metabolic activation (-S9), but 

no inhibition occurred at the same concentration in 

the presence of activation (+S9). The same effect 

was produced in the P.I. (plate) test with strain 

GY5027, confirming detoxication by S9. No 

inducing activity was detected

870.6200a

Acute 

neurotoxicity 

screening battery

Study requirement waived HASPOC memo TXR No. 0056809, dated 10/29/13

870.6200b

Subchronic 

neurotoxicity 

screening battery

Study requirement waived HASPOC memo TXR No. 0056809, dated 10/29/13

870.6300

Developmental 

neurotoxicity

Not required

870.7485

Metabolism and 

pharmacokinetics

(Sprague-Dawley 

rat)

MRID 00099355 (1976)

MRID 00247183 (1976)

14C-fosetyl-Al

250 mg/kg/day for 7 days

Fosetyl-Al is rapidly metabolized/hydrolyzed to give 

ethanol and phosphite; ethanol is oxidized to mainly 

CO2 (60%), which is excreted in exhaled air; ≈26% 

is excreted via urine (metabolite phosphorous acid, 

which is not oxidized to phosphate); 3%-4% was 

excreted via feces

870.7600

Dermal 

penetration

MRID 00143578 (1984)

4μg/cm2 (human)

Acceptable 

Rate of penetration <1% in 6-16 hour period

870.7800

Immunotoxicity

Study requirement waived HASPOC memo TXR No. 0056809, dated 10/29/13
Page 26 of 36

Appendix B. Physical/Chemical Properties

Table B1. Physical/Chemical Properties of Fosetyl-Al1

Structure 

Common Name Fosetyl-Al

IUPAC Name Aluminum ethyl hydrogen phosphonate

CAS Name Aluminum tris (O-ethyl phosphonate)

CAS Number 39148-24-8

Melting Point Range >200 °C

pH, 1% aqueous 

suspension

not available

Density not available

Water solubility 120 g/L @ 20oC

Solvent solubility in g/L @ 

20oC

Methanol = 920; acetone = 13; propylene glycol =80; ethyl acetate = 5; 

acetonitrile = 5; hexane = 5.

Vapor pressure <0.013 mPa (25oC)

Dissociation constant, pKa 0.8

Octanol/water partition 

coefficient

-2.7 (pH 4)

UV/visible absorption 

spectrum

not available
Page 27 of 36

Appendix C. International Residue Limit Status

International Residue Limits 

Fosetyl-Aluminum (123301; 9/29/13)

Summary of US and International Tolerances and Maximum Residue Limits 

Residue Definition:

US Canada Mexico1 Codex

40 CFR 180.415:

Plant: Parent only [Aluminum tris (Oethylphosphonate)]

Livestock: None

aluminum tris(O-ethylphosphonate) None

Commodity Tolerance (ppm) /Maximum Residue Limit (mg/kg)

US Canada Mexico1 Codex

Avocado 25 25

Banana 3.0

Bushberry subgroup 13B 40 40 aronia berries, buffalo currants, Chilean 

guavas, currants, elderberries, European 

barberries, gooseberries, highbush 

blueberries, highbush cranberries 

honeysuckle, huckleberries, jostaberries, 

lingonberries, lowbush blueberries, native 

currants, salal berries, saskatoon berries 

(juneberries), sea buckthorn

Caneberry subgroup 13A 0.1 0.05 blackberries, loganberries, 

raspberries, wild raspberries

Cranberry 0.5

Fruit, citrus, group 10 5.0 9 Australian (desert limes, finger limes, 

round limes), brown river finger limes, 

calamondin, citrus citron, citrus hybrids, 

grapefruits, kumquats, lemons, limes, 

Mediterranean mandarin, mount white 

lime, New Guinea wild limes, oranges, 

pummelos, Russell River limes, satsuma 

mandarins sweet limes, tachibana oranges, 

Tahiti limes, tangelos, tangerines, tangors, 

trifoliate oranges, uniq fruits

Fruit, pome, group 11 10 1 Apples

Ginseng 0.1 0.05 ginseng roots

Hop, dried cones 45

Juneberry 40 40

Lingonberry 40 40

Nut, macadamia 0.20 0.2

Onion, bulb 0.5 0.5 dry bulb onions

Onion, green 10.0 10 green onions

Pea, succulent 0.3 0.3 succulent shelled (english peas, garden 

peas, green peas, peas, pigeon peas)

Pineapple 0.1 0.1

Salal 40 40 salal berries

Strawberry 75 75

Tomato 3 3

Turnip, greens 40 40 turnip tops
Page 28 of 36

Summary of US and International Tolerances and Maximum Residue Limits 

Residue Definition:

US Canada Mexico1 Codex

Turnip, roots 15 15

Vegetable, brassica, 

leafy, group 5

60 60 bok choy Chinese cabbages, broccoli, 

cabbages, cauliflowers, Chinese broccoli, 

mustard greens

Vegetable, cucurbit, 

group 9

15 15 cantaloupes, cucumbers, squash

Vegetable, leafy, except 

brassica, group 4

100 100 celery, lettuce, spinach

MRLs With No US Equivalent

Fat of (cattle, goats, 

hogs, horses, and sheep)

0.05

Meat of (cattle, goats,

hogs, horses, and sheep)

0.05

Meat byproducts of 

(cattle, goats, hogs, 

horses, and sheep)

0.05

Milk 0.02

Rutabaga roots 15

Completed: M. Negussie; 10/17/13

1Mexico adopts US tolerances and/or Codex MRLs for its export purposes.

(c) Tolerances with regional registrations. Tolerances with regional registration, as defined in § 180.1(l), 

are established for residues of the fungicide aluminum tris (O -ethylphosphonate), including its metabolites 

and degradates, in or on the commodities in the table in this paragraph. Compliance with the tolerance 

levels specified in this paragraph is to be determined by measuring only aluminum tris (O -

ethylphosphonate), in or on the commodity.

Commodity Parts per million

Asparagus 0.1

Grape 10
Page 29 of 36

Appendix D. Occupational and Residential Exposure Algorithms

Occupational (agricultural):

The exposure methodology used to calculate inhalation exposure assessment for occupational 

handlers is detailed on the Agency website: http://www.epa.gov/pesticides/science/handlerexposure-data.html

The unit exposures used to calculate handler inhalation exposure are presented in the March 

2013 Occupational Pesticide Handler Unit Exposure Surrogate Reference Guide, also available 

at the Agency website: http://www.epa.gov/pesticides/science/handler-exposure-table.pdf

Occupational (seed treatment):

Occupational Handler Non-Cancer Exposure and Risk Estimate Equations

Potential daily exposures for occupational handlers were calculated using the following 

formulas:

Daily Exposure (mg ai /day) = UE (mgai / lb of seed) * AR (lb ai /100 lbs of seed) * AT (Amount of seed treated

/day) * 1E-3 mg/μg

Where :

Daily Exposure = Amount (mg ai/day) that is available for dermal or inhalation absorption,

UE = Unit Exposure (μg ai / lb ai),

AR = maximum application rate according to proposed label (lb ai /100lbs of seed), and

AT = daily amount treated (lbs/day).

The daily doses were calculated using the following formula:

Average Daily Dose (mg ai/kg/day) = [Daily Exposure (mg ai/day) * Absorption (%)]

Body Weight (kg)

Where:

Average Daily Dose = Absorbed dose received from exposure to a pesticide in a given scenario (mg

pesticide active ingredient/kg body weight/day),

Daily Exposure = Amount (mg ai/day) that is available for dermal or inhalation absorption,

Absorption Factor = A measure of the amount of chemical that crosses a biological boundary such as

the skin and lungs (%), and

Body Weight = Body weight determined to represent the population of interest in a risk 

assessment (kg).

MOE = POD (typically a NOAEL in mg/kg/day) 

ADD (mg/kg/day)

Where:

MOE = Margin of Exposure: value used by HED to represent risk or risk estimates (unitless),

POD = Point of Departure,

NOAEL = No Observed Adverse Effect Level (mg/kg/day): Dose level in a toxicity study, where no 

observed adverse effects occurred in the study, and

ADD = Average Daily Dose (mg/kg/day): the absorbed dose received from exposure to a 

pesticide in a given scenario.
Page 30 of 36

Residential:

The exposure methodology used to calculate residential exposure is detailed on the Agency 

website: http://www.epa.gov/pesticides/science/residential-exposure-sop.html

Additional detail is provided below.

1.1.1 Turf, Gardens and Trees

Dermal and Inhalation Handler Exposure Algorithm

Daily dermal and inhalation exposure (mg/day) for residential pesticide handlers, for a given 

formulation-application method combination, is estimated by multiplying the formulationapplication method-specific unit exposure by an estimate of the amount of active ingredient 

handled in a day, using the equation below:

E = UE * AR * A

where:

E = exposure (mg/day);

UE = unit exposure (mg/lb ai);

AR = application rate (e.g., lb ai/ft2, lb ai/gal); and

A = area treated or amount handled (e.g., ft2/day, gal/day).

1.2 Residential Handler Dose Calculations

Dermal and/or inhalation absorbed doses normalized to body weight are calculated as:

D = E *AF / BW

where:

D = dose (mg/kg-day);

E = exposure (mg/day);

AF = absorption factor (dermal and/or inhalation); and

BW = body weight (kg).

2.0 Residential Post-application

2.1 Turf/Physical Activities on Turf

Post-application Dermal Exposure Algorithm – Physical Activities on Turf

Exposure resulting from contacting previously treated turf while performing physical activities is 

calculated as shown below. Residential post-application exposure assessment must include 

calculation of exposure on the day of application. Therefore, though an assessment can present 

exposures for any day “t” following the application, it must include “day 0” exposure.
Page 31 of 36

E = TTRt * CF1 * TC * ET

where:

E = exposure (mg/day);

TTRt = turf transferable residue on day t (μg/cm2);

CF1 = weight unit conversion factor (0.001 mg/μg);

TC = transfer coefficient (cm2/hr); and

ET = exposure time (hr/day).

If chemical-specific TTR data are available, then surface residues from the day of application 

should be used (assume that individuals could be exposed to residues immediately after 

application). However, if data are not available, then TTRt can be calculated using the following 

formula:

TTRt= AR * F * (1-FD)t * CF2 * CF3

where:

TTRt = turf transferable residue on day t (μg/cm2);

AR = application rate (lbs ai/ft2or lb ai/acre);

F = fraction of ai as transferable residue following application (unitless);

FD = fraction of residue that dissipates daily (unitless);

t = post-application day on which exposure is being assessed;

CF2 = weight unit conversion factor (4.54 x 108μg/lb); and

CF3 = area unit conversion factor (1.08 x 10-3ft2/ cm2or 2.47 x 10-8acre/cm2).

Dermal absorbed doses are calculated as:

BW

E AF D*



where:

D = dose (mg/kg-day);

E = exposure (mg/day);

AF = absorption factor (dermal); and

BW = body weight (kg).

Table D-1: Turf (Physical Activities) -- Inputs for Residential Post-application Dermal Exposure

Algorithm Notation Exposure Factor

(units) Point Estimate(s)

AR Application rate

(mass active ingredient per unit area) Up to 17.6 lbs ai/A
Page 32 of 36

Table D-1: Turf (Physical Activities) -- Inputs for Residential Post-application Dermal Exposure

Algorithm Notation Exposure Factor

(units) Point Estimate(s)

F

Fraction of AR as TTR 

following application (if 

chemical-specific data is 

unavailable)

L/WP/WDG 0.01

FD

Daily residue dissipation 

(if chemical-specific data 

is unavailable)

(fraction)

L/WP/WDG 0.1

TC

Transfer 

Coefficient 

(cm2/hr)

L/WP/WDG

Adults 180,000

Children 1 < 2 years old 49,000

Granules

Adults 200,000

Children 1 < 2 years old 54,000

ET Exposure Time

(hours per day)

Adults 1.5

Children 1 < 2 years old 1.5

BW Body Weight

(kg)

Adults 80

Children 1 < 2 years old 11

L/WP/WDG = Liquids/Wettable Powders/Water-dispersible Granules

Post-application Hand-to-Mouth Exposure Algorithm– Physical Activities on Turf

Exposure from hand-to-mouth activity is calculated as follows (based on the algorithm utilized in 

the SHEDS-Multimedia model):

E = [HR * (FM * SAH) * (ET * N_Replen) * (1- (1- SE)

(Freq_HtM/N-Replen))]

where:

E = exposure (mg/day);

HR = hand residue loading (mg/cm2);

FM = fraction hand surface area mouthed / event (fraction/event);

SAH = typical surface area of one hand (cm2);

ET = exposure time (hr/day);

N_Replen = number of replenishment intervals per hour (intervals/hour);

SE = saliva extraction factor (i.e., mouthing removal efficiency); and

Freq_HtM = number of hand-to-mouth contacts events per hour (events/hour).

and

SA * 2

Fai *DE

HR

H

hands



where:

HR = hand residue loading (mg/cm2);

Faihands = fraction ai on hands compared to total surface residue from dermal transfer coefficient 

study (unitless);
Page 33 of 36

DE = dermal exposure (mg); and

SAH = typical surface area of one hand (cm2).

Dose, normalized to body weight, is calculated as:

BW

E

D 

where:

D = dose (mg/kg-day);

E = exposure (mg/day); and

BW = body weight (kg).

Table D-2: Turf (Physical Activities) – Inputs for Residential Post-application Hand-to-Mouth Exposure 

Algorithm 

Notation

Exposure Factor

(units) Point Estimate(s)

Faihands

Fraction of ai on hands 

from dermal transfer 

coefficient study

(unitless)

Liquid formulations 0.06

Granular formulations 0.027

DE Dermal exposure (mg) Calculated (0.268)

SAH

Typical surface area of one hand (cm2), children 1 < 

2 years old 150

AR Application rate

(mass active ingredient per unit area) 17.6 lbs ai/A

HR Residue available on the hands (mg/cm2) Calculated via (DE * Faihands)/SAH

FM

Fraction hand surface area mouthed

(fraction/event) 0.127

N_Replen Replenishment intervals per hour

(intervals/hr) 4

ET Exposure time 

(hrs/day) 1.5

SE Saliva extraction factor

(unitless) 0.48

Freq_HtM Hand-to-mouth events per hour

(events/hr) 13.9

BW Body Weight

(kg) Children 1 < 2 years old 11

Post-application Object-to-Mouth Exposure Algorithm– Physical Activities on Turf

Exposure from object-to-mouth activity is calculated as follows (based on the algorithm utilized 

in SHEDS-Multimedia):

E = [OR* CF1 * SAMO * (ET * N_Replen) * (1- (1- SEO)

(Freq_OtM/N_Replen))]

where:

E = exposure (mg/day);
Page 34 of 36

OR = chemical residue loading on the object on day “t” (ug/cm2);

CF1 = weight unit conversion factor (0.001 mg/μg);

SAMO = area of the object surface that is mouthed (cm

2

/event);

ET = exposure time (hr/day);

N_Replen = number of replenishment intervals per hour (intervals/hour);

SEO = saliva extraction factor (i.e., mouthing removal efficiency); and

Freq_OtM = number of object-to-mouth contact events per hour (events/hour).

and

OR = AR * FO * CF2 * CF3

where:

OR = chemical residue loading on the object (μg/cm2);

AR = application rate (lbs ai/ft2or lb ai/acre);

FO = fraction of residue available on the object (unitless);

CF2 = weight unit conversion factor (4.54 x 108μg/lb); and

CF3 = area unit conversion factor (1.08 x 10-3ft2/cm2or 2.47 x 10-8acre/cm2).

Dose, normalized to body weight, is calculated as:

BW

E

D 

where:

D = dose (mg/kg-day);

E = exposure (mg/day); and

BW = body weight (kg).

Table D-3: Turf (Physical Activities) – Inputs for Residential Post-application Object-to-Mouth Exposure 

Algorithm 

Notation

Exposure Factor

(units) Point Estimate(s)

AR Application rate (to turf)

(mass active ingredient per unit area) Up to 17.6 lbs ai/A

FO Fraction of AR as OR following application 10.01

SAMO

Surface area of object mouthed 

(cm2/event) 10

N_Replen Replenishment intervals per hour (intervals/hour) 4

SEO

Saliva extraction factor

(fraction) 0.48

ET Exposure time 

(hours per day) 1.5

Freq_OtM Object-to-mouth events per hour (events/hr) 8.8

BW Body Weight (kg) Children 1 < 2 years old 11

1 This SOP assumes that all of the residue on the turf could be transferred to the object (e.g., object residue is 

equal to turf transferable residue).
Page 35 of 36

Post-application Incidental Soil Ingestion Exposure Algorithm– Physical Activities on Turf

Exposure from incidental soil ingestion is calculated as follows:

E = SRt * SIgR * CF1

where:

E = exposure (mg/day);

SRt = soil residue on day "t" (μg/g);

SIgR = ingestion rate of soil (mg/day); and

CF1 = weight unit conversion factor (1 x 10-6g/μg).

and

SRt = AR * FS * (1-FD)

t

* CF2 * CF3 * CF4

where:

SRt = soil residue on day "t" (μg/g);

AR = application rate (lbs ai/ft2or lb ai/acre);

FS = fraction of ai available in uppermost cm of soil (fraction/cm);

FD = fraction of residue that dissipates daily (unitless);

T = post-application day on which exposure is being assessed;

CF2 = weight unit conversion factor (4.54 x 108μg/lb);

CF3 = area unit conversion factor (1.08 x 10-3ft2/cm2 or 2.47 x 10-8acre/cm2); and

CF4 = soil volume to weight unit conversion factor (0.67 cm3/g soil).

Dose, normalized to body weight, are calculated as:

BW

E

D 

where:

D = dose (mg/kg-day);

E = exposure (mg/day); and

BW = body weight (kg).

Table D-4: Turf (Physical Activities) – Inputs for Residential Post-application Incidental Soil Ingestion 

Exposure 

Algorithm 

Notation

Exposure Factor

(units) Point Estimate(s)

AR Application rate

(mass active ingredient per unit area) Up to 17.6 lbs ai/A

FS Fraction of AR available in uppermost 1 cm of soil

(unitless) 1

FD

Daily residue dissipation

(fraction) 0.1

SIgR Soil ingestion rate (mg/day) 50
Page 36 of 36

Table D-4: Turf (Physical Activities) – Inputs for Residential Post-application Incidental Soil Ingestion 

Exposure 

BW Body weight (kg) Children 1 < 2 years old 11