UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

JUN 262012 

MEMORANDUM 

OFFICE OF CHEMICAL SAFETY 

AND POLLUTION PREVENTION 

SUBJECT: BEAD Chemical Profile for Registration Review: Triphenyltin Hydroxide 

(TPTH) also known as Fentin Hydroxide (083601) 

FROM: 

THRU: 

TO: 

Tara Chandgoyal, Plant Pathologist 

Biological Analysis Branch 

Cynthia Doucoure, Environmental Protection Specialist (J,~ Science Information and Analysis Branch 

John Faulkner, 'Economist tiM ~ __ I . tJ L A AA J'\ 

Economic Analysis Branch (7'1.7' y, l ~UV\l(/ \ 

Biological and Economic Analysis Division (7503P) 

Biological 

ArnetJones,Chief 

Analysis Branch 

~~ (/ 

Diann Sims, Chief £J.~ Science Information and Analysis Branch 

Sl ~ Timothy Kiely, Chief ~ 

Economic Analysis Branch 

Biological and Economic Anal is Division 03P) 

Susan Bartow, Chemical Review Manager 

Risk Management and Implementation Branch 4 

Pesticide Re-evaluation Division (7508P) 

Product Review Panel date: May 30, 2012 

INTRODUCTION 

The purpose of this document is to convey usage information and a broad overview of the pest 

management roles of pesticides that are beginning to undergo registration review. The 

anticipated audience consists of the team of EPA staff currently evaluating the registration status 

oftriphenyltin hydroxide (TPTH) also know as fentin hydroxide, and eventually the general. 

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public. This document builds upon the data already provided in the "Usage and Label Use Data 

Packages" that are also provided to Registration Review teams by BEAD. The document is 

based on information and data available to BEAD as of June 1,2012. 

Triphenyltin hydroxide (TPTH) was first registered in the U.S. in 1971 for use as a fungicide. 

The TPTH Reregistration Eligibility Decision (RED), which includes a comprehensive 

reassessment of the use patterns of registered products for use on pecans, potatoes, and sugar 

beets, was approved on September 30, 1999. TPTH is in an organotin compound that belongs to 

Group 30 fungicide (FRAC, 2012). This fungicide is non-systemic with mainly protective action. 

It inhibits oxidative phosphorylation, ATP Synthase enzyme in fungi to inhibit/restrict their 

growth. This fungicide is effective against early and late blight of potatoes (caused by Alternaria 

and Phytophthora spp., respectively), leaf spot of sugarbeets (caused by Cercospora sp.), and 

pecan scab (caused by Fusicladium effusum). 

COMMON FORMULATIONS AND APPLICATION METHODS 

Triphenyltin hydroxide (TPTH) is formulated as a wettable powder and flowable concentrate. 

Application methods include ground and aerial sprays, as well as chemigation (irrigation supply 

water system). 

USE SITES 

Agricultural Use Sites 

Triphenyltin hydroxide (TPTH) is registered for use on pecans, potatoes and sugarbeets 

Non-Agricultural Use Sites 

TPTH is not labeled for use on non-agricultural sites. 

USAGE 

Agricultural Use Trend, 1998-2010 

TPTH use in the U.S., as reported in private market research surveys, decreased substantially 

between 1998 and 2010 as shown in Figure 1. A similar trend was found for total acres treated 

as shown in Figure 2. During the 1998-2010, agricultural usage ofTPTH averaged 

approximately 330,000 pounds annually and was applied on average to 1,460,000 acres at an 

overall average a.i. rate of 0.23 lbs/acre. 

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Figure 1: TPTH: Pounds A.I. Applied, 1998-2010 

700,~ ~----------------------------------------------------------------

1998 1999 2~ 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 

Year 

Source: Proprietary Data, 1998-2010 

Figure 2. TPTH: Total Acres Treated, 1998-2010 

3IOOO,~ -r-------------------------------------------------------------

1998 1999 2~ 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 

Year 

.. . 

Source: Proprietary Data, 1998-2010 

Agricultural Use 2006-2010 

During the 2006-2010 period, use of agricultural usage ofTPTHwas relatively stable. 

Approximately 230,000 pounds ofTPTH were applied annually to 950,000 acres on average at 

an overall average a.i. rate ofO.24Ibs/acre. The top crops in tenns of pounds ofTPTH applied 

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were pecans (62%) followed by sugar beets (29%) and potatoes (9%). See Figure 3. While there 

were similar results for total acres treated, the percentage of potato acres treated was higher than 

the percentage of pounds a.i. applied, implying that application rates are somewhat lower than 

the overall average application. The percentage of pecan acres treated was lower than the 

percentage of poUnds applied, which means the application rate is somewhat higher than the 

overall average application rate. See Table 1. 

Figure 3. TPTH Usage: Top Crops, 2006-2010 

Pounds A.I. Applied Total Area Treated 

Source: Proprietary Data, 2006-2010 

Table 1. TPTH: Average Application Rates for Potatoes, Pecans, and Sugarbeets 

Crop-II .iII % ofAvg. Avg. Pounds % ofAvg. Avg. Total Avg A.I. Rate 

PoundsA.I. A.I. Applied Total Area Area (lbs a.i. 

IIIII' Applied by Crop Treated Treated by applied/area 

(230,000) (950,000) Crop treated by trop) 

by Crop III by Crop 

Potatoes 9 20;700 17 161,500 0.13 

Pecans 62 142,600 52 494,000 0.28 

Sugarbeets 29 66,700 31 294,500 0.23 

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The top states in terms of pounds ofTPTH applied were Georgia (55%) followed by Minnesota 

(22%) and North Dakota (9%). Similar results were found for total acres treated as shown in 

Figure 4. Georgia is a major producer of pecans and, as with pecans, the percent oftotal pounds 

applied in Georgia is greater than the percent of total acres treated, which means application rates 

in Georgia are higher than average. 

Figure 4: TPTH Usage: Top States, 2006-20lOr--____________ --.. 

Pounds A.I. Applied 

Source: Proprietary Data, 2006-2010 

Agricultural Usage by Crop Reporting District 

NORTH 

DAKOTA 

10% 

Total Acres Treated 

Another measure of usage is the use intensity. In this analysis, the use intensity is expressed as 

the pounds a.i. applied per acre of land in farms. This differs from the application rate, which is 

expressed as the pounds a.i. applied per treated acres. Figure 5 spatially represents TPTH's use 

intensity in the U.S., which is relatively greater in Georgia. As noted above, Georgia is a major 

producer of pecans, which are treated at higher-than-average rates, leading to relatively high use 

intensity. Use in Alabama also likely reflects use on pecans, but acreage in pecans is probably a 

smaller proportion of total farmland, which leads to a lower use intensity than observed in 

Georgia. The medium intensity area in Minnesota and North Dakota shows areas in potato and 

sugar beet production and may indicate a high proportion of those crops in total farmland and/or 

a relatively high percent of the crop treated with TPTH. 

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Figure 5. TPTH Usage by Crop Reporting District (2006-2010) 

Average Pounds Per 

1,000 Acres of Farmland 

_ <0.6 

0.6 - 1.9 

D 2.0-3.8 

3.9 - 15.0 

_ 15.1-26 

This is a map of agricultural pesticide usage at the Crop Reporting District (CRD) leveL CRDs are boundaries 

created by USDA NASS which are aggregates of counties (USDA, 2010). Pesticide usage is displayed as 

average pounds (for the years 2006-2010) per 1,000 acres of farmland in a CRD to normalize for the variation 

in farmland between CRDs. Farmland acreage was obtained from USDA (2007). 

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

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

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

due to either the lack of pesticide use in the region or non-participation in the agricultural surveys. In addition, 

across the years, there may be variations in the specific crops included in the CRD survey. This may result in a 

lower annual average for the CRD. 

Sources: 

Proprietary Data. 2006-2010 

USDA, 2006-2010. NASS Crop Reporting Districts. 

USDA, 2007. Census of Agriculture. 

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BIOLOGICAL ASPECTS RELEVANT TO TPTH (TRIPHENYL TIN HYDROXDE) 

Triphenyltin hydroxide (TPTH) belongs to Group 30 fungicide (FRAC, 2012). This group of 

fungicides has low to medium risk of developing resistance in phytopathogenic fungi. 

Cercospora beticola causes leaf spot disease of sugar beets. TPTH was widely used on sugar 

beets (MN, ND, and ID) for the control of this fungal pest for many years. As a result of this the 

fungal pathogen developed resistance/tolerance against it (Briere et al., 2001; Weiland, 2002). In 

2000-2001 tetraconazole and azoxystrobin were registered for the control of Cercospora beticola 

on sugar beets. The growers started using the new fungicides and TPTH use on sugarbeets 

declined. 

HISTORY OF BEAD ASSESSMENTS FOR TPTH (TRIPHENYL TIN HYDROXIDE) 

There are no recent BEAD assessments (including section 18 use) for triphenyltin hydroxide in 

BEAD's Official Records. 

INFORMATION THAT MAY BE USEFUL FOR BEAD'S FUTURE WORK ON 

TPTH (TRIPHENYL TIN HYDROXIDE) 

Obtaining additional information on the following items would improve future BEAD 

assessments of the importance of TPTH and may be required as part of the registration review of 

this pesticide. 

This fungicide is registered for use on three crops (pecans, potato and sugar beets). BEAD is not 

aware of any additional information that is necessary to improve future assessments as it relates 

to registration review of this fungicide. 

REFERENCES 

Briere, S.C., Franc, G.D and Kerr, E. D. 2001. Fungicide Sensitivity Characteristics of 

Cercospora beticola Isolates Recovered from the High Plains of Colorado, Montana, Nebraska, 

and Wyoming. Benzimirnidazole and Triphenyltin Hydroxide. http://assbtjsbr.org/JSBRNo138/JSBRVoI38N02pll1toI20FungicideSensitivityCharacteristicsofCerecospo 

rabeticolaIsolatesRecoveredfortheHighPlains.pdf 

FRAC. 2012. Fungicide Resistance Action Committee. 

http://www.frac.info/frac/publication/ anhangiFRA C%20Code%20List%2020 11-final. pdf 

Proprietary Data, 1998-2010 

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USDA, 2006-2010. NASS Crop Reporting Districts. Online: 

http://www.ers.usda.govlbriefinglarms/resourceregions/resourceregions.htm#nass. 

USDA, 2007. Census of Agriculture. Online: 

http://www.agcensus. usda. gOY /Publications/2007 /index.asp. 

Weiland, J. 2002. A Survey for the Prevalence and Distribution of Cercospora beticola Tolerant 

to Triphenyltin Hydroxide and Tetraconazole and Resistant to Thiophanate Methyl in 2001. 

http://www.ars.usda.gov/research/publicationslPublications.htm?seg no 115=131579 

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