UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON D.C., 20460 

OFFICE OF 

CHEMICAL SAFETY AND 

POLLUTION PREVENTION 

PC Code 128887 

OP Barcode 404864 

Date September 26, 2012 

MEMORANDUM 

SUBJECT: 

FROM: 

Review of two reports (MRIDs 48904003 and 48904004) as the Response to a 

Data Call-In (DCI) for an Environmental Chemistry Method (ECM) and an 

Independent Laboratory Validation (I LV) for Tribenuron-Methyl 

James Lin, Environmental Engineer ~ Environmental Risk Branch 2 

Environmental Fate and Effects Division 

./) ,...., ./J · I o.. _ ·v _ }2.. REVIEWERS: Greg Orrick, Environmental Scientist ~ U~ 1 t?-0 

Environmental Risk Branch 2 

THROUGH: 

TO: 

Environmental Fate and Effects Di~isio 

Brian Anderson, Chief /rt <IJ ___.-

Environmenta

Environmental 

l 

Risk 

Fate and 

Branch 

Effects 

2 

Divi

v 

sion 

~ (7507P) 

Kaitlin Keller, Risk Manager Review 

Michael Goodis, Risk Manager 

Risk Management and Implementation Branch 3 

Pesticide Re-evaluation Division (7508P) 

The registrant, E. I. duPont de Nemours Company, has submitted two reports (MRIDs 48904003 

and 48904004) in response to a Data Call-In (DCI) for an Environmental Chemistry Method 

(ECM) and an Independent Laboratory Validation (IL V) to fulfill guideline 835.6100 (terrestrial 

field dissipation) for tribenuron-methyl. Based on the discussions below, the submitted two 

reports are not reviewable. A modified ECM with higher acceptable quantitative recoveries for 

tribenuron-methyl and an acceptable IL V for the modified ECM are needed to fulfill this DC!. 

Both reports contain data confidentiality markings (e.g., "Trade Secret") and statements that limit 

their release to the public and to foreign parties. The Agency requests resubmission of the ECM 

and ILV reports with data confidentiality markings or statements other than the standard 

Statement ofNo Data Confidentiality removed so that the reports can be publicly posted on the 

Agency's website. 

tlltut 1111 nm IIIII I 11111 2088035 
MRID 48904004 - Analytical Method for the Determination of 13 DuPont Sulfonylurea 

Herbic~des in Soil Using LCIMSIMS 

The method is designed for multi-analytes of 13 sulfonylurea (SU) herbicides in soil. Due to 

poor stability in aqueous solutions at low pH, tribenuron-methyl recoveries were poor and a 

modified method was described for analysis of tribenuron-methyl. To fulfil the DCI for 

tribenuron-methyl, submission of the modified method is recommended with quantitative 

recoveries demonstrated by internal validation. ECM recoveries are quanitative when the mear1 

value is 70-120% and the relative standard deviation is less than 20%. The Agency has no 

position on whether to include as analytes any of the other 12 SUs. 

MRID 48904003 -Suitability of DuPont-5082, Revision No.1 as a Monitoring Methed for 

Azimsulfuron, Bensulfuron-Methyl, Chlorimuron-Ethyl, Chlorsulfuron, EthametsulfuronMethyl, Flupyrsulfuron-Methyl, Metsufuron-Methyl, Nicosulfuron, Rimsulfuron, 

Sulfometuron-Methyl, Thifensulfuron-Methyl, Tribenuron-Methyl and TriflusulfuronMethyl in Soil 

TheIL V report was not properly prepared, since the independent laboratory (University of Iowa 

Hygienic Laboratory) did not prepare the report. There was no documentation of any contact 

between the independent laboratory and the developers of the method. The ECM was not 

validated, since recoveries for tribenuron-methyl were poor. Mean recoveries were 54 and 67%, 

respectively for German soils and American soils. In order for an ECM and its associated IL V 

report to be reviewable, the internal and independent validations and their documentation should 

be consistent with OCSPP guideline 850.6100 and both validations should produce quantitative 

recovenes. 

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