UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C.  20460

     OFFICE OF	

PREVENTION, PESTICIDES

AND TOXIC SUBSTANCES

MEMORANDUM    

Date:  	 		February 5, 2009

SUBJECT:				Amendment: Prothioconazole.  Human Health Risk Assessment
for Proposed Section 3 Seed Treatment Use on Wheat, Barley, and
Triticale, Plus Increase Tolerance on Forage of Wheat, Barley, and
Triticale.

PC Code:  113961	DP Barcode: D361313

Decision No.: 386009 & 388700	Registration No.: 264-825 & 264-RNTE

Petition No.: 7F7279	Regulatory Action: Section 3 Registration

Risk Assessment Type: Single Chemical Aggregate	Case No.: NA

TXR No.: NA	CAS No.: 178928-70-6

MRID No.: 47277008, 47293901 & 47337401	40 CFR: 180.626



FROM:			Barry O’Keefe, Risk Assessor

			Myron Ottley, Toxicologist

			Registration Action Branch 3

			Health Effects Division (7509P)

THROUGH:	Paula Deschamp, Branch Chief

			Registration Action Branch 3

			Health Effects Division (7509P)

		

TO:					Bryant Crowe/Tony Kish, RM Team #22

				Fungicide Branch

				Registration Division (7505P)

This memorandum is to amend the recently completed HED risk assessment
document for new seed treatment uses of prothioconazole and the increase
in the wheat forage tolerance (DP347123, B. O’Keefe, 1/5/09).  The
following three changes are needed.

On pages 6 and 16 the document states that chronic studies showed
toxicity to the lymphatic system.  The reference to toxicity to the
lymphatic system should be excluded at this time.  In one chronic study
in the rat (but not in the mouse or dog), blood leukocyte counts were
significantly elevated at the high dose level (750 mg/kg/day) along with
increased thrombocyte counts and decrease hemoglobin.  However, this
finding is made in the presence of toxicity to a broad range of organ
systems such as the liver, urinary bladder, kidney, thyroid, and
decreased body weight gains.  Furthermore, no signs of immunotoxicity,
including evidence of toxicity to the lymphatic system, were observed at
dose levels up to 400 mg/kg/day in the non-guideline immunotoxicity
study in the mouse.

A footnote under Table 3.2.4.1, on page 21 of the document, should be
removed since it is no longer valid, because the FQPA safety factor has
been reduced from 10X to 1X.  The footnote is as follows: “For acute
and chronic dietary (food and water) risk assessments, the 10x FQPA SF
has been retained in the form of a UFdb (10x) for the lack of NOAEL and
a LOAEL from the developmental neurotoxicity study, regarding some
neurotoxic endpoint (peripheral nerve lesions and brain
morphometrics).”

The Data Needs Section 9.0 should be amended to include the data
requirement for submission of a new guideline immunotoxicity study
(Guideline Number 870.7800).  This is a new data requirement under 40
CFR Part 158 as apart of the data requirements for registration of a
pesticide (food and non-food uses).

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