UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON D.C., 20460 

## 'JUN 

## i 

## 4: 2011
MEMORANDUM SUBJECT: Typical Use Datafor Chlorpyrifos OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION



### FROM: Jonathan Becker, Ph.D., Senior Science Advisor

# f-Il**~** Biological Analysis Branch , /



### THRU:

TO: Katherine Stebbins, Biologist**,** 

### Science Infonnation and Analysis Branch Biological and Economic Analysis Division (7503P) Arnet Jones, Chief Biological Analysis Branch Diann Sims, Chief

# A1~ Science Information and Analysis Branch Biological and Economic Analysis Division (7503P) Rochelle Bohaty, Chemist Environmental Risk Branch III Environmental Fate and Effects Division (7507P) 

### BEAD ProductReview PanelDate: 6/22/2011 

### INTRODUCTION Typical use data for chlorpyrifos was requested by EFED for use in a drinking water assessment. Inthis memorandum, BEAD is providing typical use information such as the application rate and number ofapplications ror chlorpyrifos used on apples, cherries, com, grapes, grapefruit, lemons, oranges, onions"pecans, and sugarbeets. These data are available from a proprietary usage data source and are based onprivate matketresearch surveys ofpesticide use in agriculture. In addition, data from the USDA National Agricultural Statistics Service (NASS) were also used as a secondary source to ensure thatthe usage was representative for each ofthe crops reported inthis dataset. In additionto the national-level data, further refinement for three crops (com, sugar beets, and grapes) was requested by EFED for use in site-specific water models. Inthis memorandum, BEAD is also providing refined pesticide use and productionpractice information for com grown 

### in Kansas, sugarbeets grown in Minnesota, and grapes grown inCalifornia.METHODS National Data Usage datafor chlorpyrifos use on apples, corn, grapes, grapefruit, lemons, oranges, onions, pecans, and sugarbeets was compiled from a**d~tabas~** ofpesticide usage data. Forthe data years 2006-2010, the following information was queried'·atthe crop level for chlorpyrifos: pounds AI applied, total areatreated (includes multiple applications to the same field), base areatreated (the areatreated only once), crop area grown, percentcrop treated, average AI rate, the number of survey respondents, and the average number ofapplications (row crops only). To calculate the average number ofapplications for the specialty crops, the total areatreated was divided by the base area treated to get anestimated value.

- In addition to the average application rate data, a rate distribution was generated to calculate an upperbound rate for each crop. The datawere generated using the AI Rate Range variable(set from 0-7 and at an interval of0.25) along with the total acres treated. To calculate the upperbound rate, the total areatreated reported at eachrate interval was divided bythe cumulative total areatreated across all intervals. A running total was fncluded to showthe cumulative percentile at each rate increment and therate associated withthe 90th percent was reported as the upperbound rate. Therefore, the upperbound rate inthis analysis can be defined as the rate atwhich 90% (or as close to 90% as possible) ofthe acres treated with chlorpyrifos were treated at orbelow. Afterthe datawere compiled, a comparisonwas made to the most recent datathat were available from USDANASS. This comparison was possible for all crops except for pecans and sugarbeets which are not surveyed by NASS. SUMMARY Afterreviewing the data from both sources, BEAD recommends using the maximum number of applications andthe upperbound rate values presented in Table 1. Table 1. Typical Use Patterns for Chlorpyrifos Used on Selected Crops (2006-2010) Average Number of Numberof Application Upperbound rate* applications applications Rate (Lbs. (Lbs. AIlAcre) Crop (average) (range) AIlAcre) 

### percentile inparenthesis Com 1.0 1.0-1.1 0.9 1.25 (84%); 1.5 (97%) Sugar Beets 1.2 1.1-1.3 0.8 1.5 (88%) Apples 1.2 1.1-1.3 1.5 1.75 (52%); 2.0 (99.9%) Lemons. 1.0 1.0-1.1 3.5 5.0 (88%) Grapefruit 1.3 1.0-2.1 2.1 2.75 (90%) Oranges 1.4 1.2-1.6 2.5 5.75 (81%); 6.0 (100%) Onions 1.1 1.0-1.1 0.9 2 1.0 (70%); 1.25 (99.8%)2 Cherries 1.1 1.0-1.1 1.5 2.0 (99.6%) Pecans 2.2 2.0-2.8 0.9 1.25 (91%)

2Grapes, Raisin 

### 1.2 1.0-1.9 1.9 2.0 (98%) Grapes, Table 

### 1.1 1.0-1.4 2.7 2.25 (62%); 4.0 (100%) Grapes, Wine 

### 1.2 1.0-1.4 2.0 2.0 (99.7%) "All Grapes" 

### 1.2 1.0-1.4 2.2 Not availablel Source: GfK Kynetec. 2006-2010 1Recommend 4.0 pounds/A (from table grapes) as a conservative value 2 Higher values were reported in NASS. For a conservative estimate, BEAD recommends the following: Avg. Rate: 1.4lbs. AI/A; Number ofapplications: 1, Upperbound Rate (90th percentile): 2.5 pounds/A (USDA NASS, 2007) 

### Recommendations for FurtherRefinement ofThree Chlorpyrifos Use Scenarios Corn in Kansas. Based onproprietary data (GfK Kynetec, 

### 2010) for com, chlorpyrifos is primarilyusedby growers to control rootworm. BEAD recommends that a ground application be modeled. BEAD also recommends that the midpoint ofthe "most active"**us~** planting date range for this state (April 

### 15 to May 

### 15) be used for the model input (USDA, 

### 2010). Sugarbeets in Minnesota. Based onproprietary data (GfK Kynetec, 

### 2010) and on the Minnesotaproduction guide for sugarbeets, chlorpyrifos is being used by growers to control sugarbeet maggot. BEADrecommends using a 

### 1.5 lb ai 

### I A rate for the application ofgranular chlorpyrifos at-plant and a 

### 0.5 lb ai 

### I A rate for the second post-emergent application using the application instructions provided by Kahn 

### (2011). BEAD also recommends that the midpoint of the "most active" usual planting date range for this state (April 

### 24 to May 

### 18) be used for the model input (USDA, 

### 2010). Grapes in California. Based on proprietary data (GfK Kynetec, 

### 2010) and pest management guidelines for grapes (UC IPM, 

### 2009), chlorpyrifos is being used by grower& to control mealybug. BEAD recommends modeling a late February to early March delayed dormant application followed by a second chlorpyrifos application in late June or July (UCIPM, 

### 2009). REFERENCES GfK Kynetec. 

### 2006-2010 Kahn, M
. 

### 2011. Production Guide
. Sugarbeet Research andEducation Board ofMinnesota and NorthDakota. Available at: http://www.sbreb.orglproductionlproduction.htm UCIPM. 

### 2009. Pest Management Guidelines: GRAPE. Publication 

### 3448, University of CaliforniaAgriculture andNatural Resources, UC Statewide Integrated Pest Management Program. Available at: http://www
.ipm.ucdavis.edulPDF/PMG/pmggrape.pdf



### 3USDANASS. 2007. Agricultural Chemical Usage-2006 Vegetables Summary-Available at: http://usda.mannlib.comell.edulusdalnass/ AgriChemUsVeg//2000s/2007 /AgriChemUsVe g-07-25-2007_revision.pdf USDA 2010. Field Crops

- Usual Planting and Harvesting Dates
. Agricultural Handbook Number 628. United States Department ofAgriculture, National Agricultural Statistics Service. Available at: http://usda.mannlib.comell.edulusdalcurrentlplanting/planting-l0- 29-201O
.pdf

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