UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

JUN 0 9 2015 

MEMORANDUM 

OFFICE OF CHEMICAL SAFETY 

AND POLLUTION PREVENTION 

SUBJECT: BEAD Chemical Profile (BCP) for Registration Review: Thi ram (079801) 

FROM: 

THRU: 

Tara Chandgoyal, Ph.D., Pathologist 

Biological Analysis Branch few ~ 

Don 

Science 

Atwood, 

Information 

PhD., Entomologist 

and Analysis Branch 

/7 ~ ~ ~ 

Elizabeth Hill, Economist 

Economic Analysis Branch 

Biological and Economic Analysis Division (7503P) 

Arnet Jones, Chief 

Biological Analysis Branc 

TO: Wilhelmena Livingston, Chemical Review Manager 

Risk Management and Implementation Branch IV 

Pesticide Re-evaluation Division (7508P) 

Peer Review Panel date: May 6, 2015 

Page 1 
SUMMARY 

Thiram has been registered in the U.S. since 1948 for use as a non-systemic, protectant 

dithiocarbamate fungicide. Thiram is a member of the ethylene bisdithiocarbamate (EBDC) 

group of fungicides which includes the related active ingredients mancozeb and maneb (FRAC, 

2014) 

The current major agricultural use sites include strawberries, soybeans, cotton and wheat. The 

major non-agricultural use sites is ornamental turf (golf courses). According to available 

proprietary information, the highest usage of this fungicide, in terms of both total lbs applied and 

total acres treated is soybeans. 

INTRODUCTION 

The Biological and Economic Analysis Division (BEAD) Chemical Profile (BCP) provides an 

overview of the pest management roles and quantitative usage information for thiram. The BCP 

includes summaries of previous BEAD products and available public and/or private use and 

usage data for thiram to describe the role of this chemical in pest management. Additional 

information on use is available in the Thiram Label Data Report provided in the public docket 

for this chemical. Information provided in this BEAD Chemical Profile (BCP) may be used by 

stakeholders (e.g., users and registrants), Office of Pesticide Programs (OPP) risk assessors, and 

OPP risk managers, and the general public during the Registration Review process of this 

pesticide. 

AGRICULTURAL USE SITES 

Thiram is registered for crop use on strawberries, apples, and peaches. In addition, thiram is 

registered for use on dormant and non-bearing fruit trees and deciduous orchards. Thiram is also 

labeled for use as an animal repellent to protect crops from damage by rabbits, rodents, and deer. 

Thiram is registered for seed treatment use on coriander, cantaloupes, watermelon, cucumber, 

pumpkin, squash, eggplant, peppers, tomatoes, broccoli, Brussels sprouts, cabbage, cauliflower, 

collards, kale, kohlrabi, endive, lettuce, parsley, spinach, Swiss chard, rape, broccoli raab, beets, 

carrots, onions, radishes, beans (dried and succulent), sweet corn, field corn, peas, lentils, okra, 

catjang, lupine, grasses, sorghum, alfalfa, clover, vetch, barley, oats, rice, rye, wheat, triticale, 

guar, safflower, rapeseed, canola, celery, cotton, flax, mustard, peanuts, sesame seed, sugar 

beets, sunflowers, turnips, soybeans, chicory, millet, and rapeseed. 

NON-AGRICULTURAL USE SITES 

Non-agricultural use sites which are labeled for thiram application include forest trees (foliar), 

airport runways, and ornamentals (trees, plants, shrubs, vines, lawns, and turf) (foliar and seed 

treatment). 

Page 2 
FORMULATIONS AND APPLICATION METHODS 

Formulations include dust, flowable concentrate, dry flowable, emulsifiable concentrate, soluble 

concentrate, and ready-to-use liquid. Thiram formulations may be applied to apples, peaches, 

and strawberries using ground boom, aerial equipment, air blast sprayer, soil incorporation 

equipment, high and low pressure hand wand, backpack sprayer, push-type granular spreader, 

tractor-drawn drop-type spreader, paintbrush, and sprinkler can. Commercial seed applicators 

use automated machinery (slurry-type and mist-type) that mixes and applies thiram to seeds as 

they are rotated through a metal drum or cylinder; these systems are used for both liquid and dust 

treatments. On-farm liquid applicators use a portable mechanical mixing system that applies 

thiram to seeds as they are rotated through a metal cylinder. On-farm dust applicators pour 

thiram into the seed chamber of the planter and mix the product by hand with a stick or paddle, 

just prior to planting. Ornamental bulbs may be treated by dip tank application, drill box, and 

duster. 

HISTORY OF THIRAM AND BEAD PRODUCTS 

Thiram was first registered for use in the U.S. in 1948. The most recent Thiram RED was 2004. 

There have been no benefits assessments or Section 18 Emergency Exemption Requests for 

thiram in the last 10 years. An emergency exemption may indicate that there is a need for a 

particular chemical that is not registered for use on a particular site. An emergency exemption 

request may yield information about a particular chemical 's importance or value that is not found 

in other EPA records. However, a lack of Section 18 assessments by BEAD does not 

specifically indicate the relative importance of the chemical. 

THIRAM USAGE 

Agricultural Usage 

The number of acres treated with thiram remained constant at approximately 85,000 acres from 

1998 through 2008. Since 2008, the number of acres treated with thiram has significantly 

increased. In contrast, pounds a.i. applied tremendously decreased from 1998-2008. Since 2008, 

there has been a steady increase in pounds a.i. applied. These data indicate that application rates 

were much greater per acre prior to 2008 and has continued to decrease through 2012. It should 

be noted that when interpreting the data presented in this analysis that EPA's proprietary data 

source did not begin surveying fungicide seed treatments for field crops until 2006 while seed 

treatment surveys were not initiated for all other crops until 2009. 

Page 3 
350,000 5,000,000 

1', 

I ~ I 

I <i. I "t:I "'

c: I :I 

0 I Q. I 

~ 

0 ....... . -t:- ~....__..._....___. _ , 0 co CTI 0 .... N "" '<t U"l ID ,.... 00 CTI 0 .... N CTI CTI 0 0 0 0 0 0 0 0 0 0 .... .... .... CTI CTI 0 0 0 0 0 0 0 0 0 0 0 0 0 .... .... N N N N N N N N N N N N N 

Year 

..,._Pounds A.I. - .. - Total Area Treated 

Figure 1. National Thiram Usage (Lbs A.I.) from 1998 to 2012 

Source: Proprietary data, 1998-2012 

"t:I 

QI 

.... 

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~ 

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A review of total thiram usage data across all crops for the 5 years prior to the most recent RED 

(2004) and the most recent 5 years of reported usage indicates that the primary use sites have 

changed between the two periods (Tables l and 2). For the period 1999-2003, apples and 

strawberries accounted for approximately 98% of lbs applied and total acres treated. In contrast, 

for the period 2008-2012, strawberries accounted for 35% of thiram pounds applied and l % of 

total acres treated with thiram while seed treatments accounted for approximately 63% of thiram 

lbs applied and 98% of total acres treated. The decrease in usage on apples reflects the 2004 

RED which cancelled all use on apples. The change in usage from direct crop application to 

primarily seed treatment is verified by the great decrease observed in application rates for the 

two periods (Tables l and 2). Only strawberries showed consistent usage for both periods. The 

change in application method is the underlying cause of the decreased application rate suggested 

in Figure 1. Furthermore, the increased acreage planted with treated seed is responsible for the 

increasing trend in thiram usage in terms of both total lbs applied and total area treated. 

Table 1. Crops with Highest Use of Thiram (1999-2003) 

Crop Lbs A.I. % of Total Total Acres % of Total A.I. Rate 

(OOO's) Thiram Treated* Thiram 

Lbs (OOO's) Treated 

Applied Acres 

Apples 669 56.6 248 48.7 2.696 

Strawberries 493 41.7 254 49.8 1.945 

Pears 8 0.7 2 0.4 4.476 

Cherries 8 0.6 ..., 

.) 0.7 2.25 

Peaches 4 0.3 2 0.4 1.955 

*Total Acres Treated sums all acres treated for a crop, including those acres that receive multiple 

treatments. 

Source: Proprietary Data, 1999-2003 

Page4 
Table 2. Crops with Highest Use of Thiram (2008-2012) 

Crop Lbs A.I. % of Total %of A.I. 

(OOO's) Total Acres Total Rate 

Thi ram Treated* Thi ram 

Lbs (OOO's) Treated 

Applied Acres 

Soybeans (seed treatment) 252 45 6,914 61.2 0.036 

Strawberries 199 35 113 1 l.758 

Wheat, Winter (seed treatment) 50 9 1,277 11.3 0.039 

Cotton (seed treatment) 35 6 2,302 20.4 0.015 

Wheat, Spring (seed treatment) 18 3 585 5.2 0.031 

*Total Acres Treated sums all acres treated for a crop, including those acres that receive multiple treatments. 

Source: Proprietary Data, 2008-2012 

While strawberries, soybeans, and cotton account for approximately 90% of total lbs of thiram 

applied, strawberries hve the greatest percent crop treated at 20% (Table 3). This indicates that 

thiram use is still important to strawberry production. Furthermore, as indicated in Table 2, 

apples are no longer a driver for thiram usage and the apple data shown in Table 3 are an artifact 

of the usage reporting period of the Screening Level Usage Analysis (SLUA). 

T a bl e 3 P . ercen tC rop T rea t e d W I "th Th' 1ram 2004 - 2012 

Crop Percent Crop Treated 

Avg. Lbs. A.I. Average Maximum 

Apples 50,000 <2.5 10 

Strawberries 50,000 20 30 

Soybeans 40,000 <2.5 5 

Wheat 20,000 <2.5 <2.5 

Cotton 6,000 5 15 

*Total Acres Treated sums all acres treated for a crop, mcludmg those acres that receive multiple treatments. 

Source: EPA SLUA for Thiram, 2014 

States with highest usage of thiram in terms of lbs a.i. applied and acres treated for the period 

immediately prior to the 2004 RED and the most recent five years of usage data are presented in 

Tables 4 and 5. State data also indicate a shift in thiram usage as California, Florida, and 

Michigan are the only states of greatest thiran1 usage common to both time periods. In addition, 

Florida is the only state which showed consistent lbs applied and total thiram acres treated across 

the time periods. In contrast, both California and Michigan indicated. a substantial decrease in lbs 

of thiram applied but an increase in number of thiram treated acres. As noted previously, this 

again reflects the changing nature of thiram usage from crop application to seed treatment. As 

previously mentioned, seed treatment usage data was not fully recorded for all crops by EPA' s 

proprietary data source until 2008. Nevertheless, California was the greatest applier of thiram in 

terms oflbs a.i. from both 1999-2003 and from 2008-2012. However, in terms of total acres 

treated, thiram usage significantly decreased in California with Indiana representing most acres 

treated in 2008-2012. Overall, lbs of thiram applied has decreased by 52% while total acres 

treated has increased by 2100%. 

Page 5 
Table 4. States with Highest Use of Thiram (1999-2003) 

Crop Lbs A.I. % of Total Total Acres . % of Total A.I. Rate 

(OOO's) Thiram Lbs Treated* Thi ram 

Applied (OOO's) Treated Acres 

California 391 33.l 183 36.0 2.133 

Washington 257 21.8 74 14.5 3.486 

New York 171 14.5 65 12.7 2.647 

Pennsylvania 102 8.6 58 11.5 1.745 

Florida 90 7.6 67 13.1 1.357 

Michigan 45 3.8 13 2.6 3.416 

West Virginia 42 3.6 19 3.8 2.202 

Virginia 32 2.7 12 2.3 2.779 

Oregon 2 1 1.7 6 1.2 3.34 

North Carolina 18 1.5 7 1.4 2.497 

*Total Acres Treated sums all acres treated for a crop, including those acres that receive multiple treatments. 

Source: Proprietary Data, 2008-2012 

Table 5. States with Highest Use of Thiram (2008-2012) 

Crop Lbs A.I. % of Total Total Acres % of Total A.I. Rate 

(OOO's) Thiram Lbs Treated* Thi ram 

Applied (OOO's) Treated Acres 

California 125 22.0 339 3.0 0.368 

Indiana 111 19.6 3,040 26.9 0.036 

Florida 91 16.0 77 0.7 1.18 

Illinois 78 13.8 2,059 18.2 0.038 

Ohio 45 7.9 1,225 10.8 0.037 

Texas 24 4.2 1,502 13.3 0.016 

Kentucky 16 2.8 444 3.9 0.036 

Michigan 14 2.4 326 2.9 0.042 

Montana 11 1.9 348 3.1 0.031 

*Total Acres Treated sums all acres treated for a crop, including those acres that receive multiple treatments. 

Source: Proprietary Data, 2008-2012 

Page 6 
Geographic Distribution of Thiram Use 

Pounds Active Ingredient 

per 1,000 Crop Acres Grown 

LJ NoData 

D <o.os 

D 0.05 - 0 .1 

. 0.1 - 1 

- 1-3 

- >3 

Figure 2. Annual average agricultural use intensity of Thiram (2008-2012). 

The average agricultural use intensity is greatest in California, Florida, and Indiana. This reflects 

use on strawberries in California and Florida, and soybeans in Indiana. Agricultural use intensity 

in the north central and northwestern states reflects use on wheat and soybeans. Use intensity in 

Texas and Mississippi results from both soybean and cotton production. 

Non-Agricultural Usage 

Data for thiram use on non-agricultural sites is limited. The only available estimate of nonagricultural use is approximately 20,000 lbs on golf courses Propri~tary Data, 2012). 

BIOLOGICAL ASPECTS RELEVANT TO THIRAM 

Thiram is a fungicide belonging to dithiocarbamate group of fungicides. It belongs to group M3 

of Fungicide Resistance Action Committee based on mode of action of fungicides (FRAC, 

2014). Thiram has multi-site contact activity and considered as a low risk fungicide without any 

Page 7 
sign of resistance developing in fungi. The dithiocarbamate group includes many other 

fungicides (such as mancozeb, maneb, zineb and ziram). 

Thiram is registered for use on many crops (such as strawberries, cotton, wheat, soybeans) to 

control many fungal pests. It is used as a standalone fungicide or in combination with fungicides 

belonging to different classes of systemic fungicides (such as carboxin, tebuconazole, 

triticonazole and metalaxyl) for controlling wide spectrum of fungal pest more effectively. 

Usually Thiram is mixed with carboxin, tebuconazole, triticonazole or metalaxyl is used for seed 

treatment. 

ROLE OF THIRAM IN PEST MANAGEMENT 

Thiram is predominantly used on soybeans (seed treatment), strawberry (foliar use), wheat (seed 

treatment) and cotton (seed treatment). Thiram seed treatment of soybeans controls seed rot, 

seedling blight and damping off caused by Fusarium spp., Rhizoctonia spp. Foliar sprays of 

thiram on strawberry controls gray mold disease (caused by Bottytis cinerae). On strawberry, 

thiram is used in alternation or combination with other fungicide (such as fenhexamid, 

cyprodinal, tludioxonil and azoxystrobin) for season long disease management. On wheat, thiram 

seed treatment controls smut diseases (caused Tilletia caries, T foelida and Ustilago nuda), seed 

rot and seedling blight caused by soil-borne fungi such as Fusarium spp. and Allernaria spp. 

Thiram seed treatment of cotton seed controls soil-borne Rhizoctonia solani that causes seed rot, 

damping-off and sore-shin. It is an important fungicide in managing plant diseases on different 

crops. 

DATA NEEDS 

The Agency currently does not have important information on thiram. Obtaining the following 

information for all registered non-agricultural sites may improve future assessments conducted 

by the Agency related to the use and importance of thiram. 

Usage 

• Total pounds active ingredient appli ed 

• Percent crop/site treated 

• Application rates: typical and maximum 

• Frequency of application 

• Application Intervals 

• Methods of application 

• Target or niche pests 

• Efficacy information/product performance 

Page 8 
REFERENCES 

FRAC. 2014. 

http://www.frac.info/frac/publication/anhang/20 l 4%20FRAC%20Code%20List.pdf. 

Assessed on December 2, 2014. 

Proprietary Data. 1999-2003 

Proprietary Data. 2008-2012 

Proprietary Data. 2012 

EPA. 2014. BEAD SLUA for Thiram 

Page 9 
APPENDIX A 

The map included herein is primarily for the use of the risk assessors in the Environmental Fate 

and Effects Division. The map provides a very broad geographical view of the average annual 

amount (in pounds) of the active ingredient applied per 1,000 acres of crop acres grown. These 

data are included in the maps because risk assessors are interested in the amount of a pesticide 

used across agricultural land. The calculated values presented in the· map are not equivalent to 

an application rate (lb ai/ A). 

The data used to make these maps have several limitations. Any interpretation of the maps 

should consider the underlying data and the associated limitations carefully. 

The numerator (annual average pounds applied) is based on private market surveys of pesticide 

use in agriculture averaged over the last five years (Proprietary Oata1 2008-2012). These surveys 

cover about 60 crops and are targeted in states that produce the majority of the crop. Although 

the surveys capture most of the use of a particular active ingredient in agriculture, there are 

several limitations to these surveys. 

• States with minor production of a surveyed crop are not sampled 

• Not all types of pesticides are surveyed in every crop in every year 

• Many specialty crops with very small acreages are not included in the survey 

The result of these limitations is that states that show no usage may actually have a small amount 

of the active ingredient being used. In some cases the displayed use intensity may be distorted 

because the surveyed crops and the reported pesticide usage may not accurately represent the 

actual pesticide usage on the crops produced in the state. 

The denominator (1 ,000 crop acres grown) was also obtained from the same private market 

survey database. The "Crop Acres Grown" variable represents the total acres grown in a given 

state of all of the surveyed crops. This value is independent of pesticide usage and pesticide 

registration. It is important to note that the surveyed crops (about 60) are sampled from states 

that are major producers of each crop. Therefore, there are cases where the actual crop acreage in 

a state is higher than that reported by crop acres grown in the survey because either that state 

and/or crop was not included in the survey. 

The reader should pay particular attention to the figure legends and realize that a map prepared 

for a particular chemical is not directly comparable to a map prepared for a different chemical as 

the legend bins will likely be different. 

Page 10