UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C.  20460

OFFICE OF              

PREVENTION, PESTICIDES

AND TOXIC SUBSTANCES 

MEMORANDUM

DATE:  	June 16, 2009 

SUBJECT:	Fenamidone – Addendum to 3/2/2009 Human Health Risk
Assessment to Support Section 3 Proposals to Add New Uses on the Root
Vegetable Subgroup 1B (except radish), Okra, Turnip Greens, Cilantro
Leaves, Grapes Grown East of the Rocky Mountains and Rotational Crop
Uses for Field Corn, Sweet Corn and Soybeans.

PC Code:  046679	DP Barcode:  D364699

Decision No.:  392843	Registration No.:  264-695

Petition No.:  7E7350, 8F7410	Regulatory Action: Section 3 Registration

Risk Assessment Type:  Single Chemical Aggregate	Case No.:  N/A

TXR No.:  N/A	CAS No.:  161326-34-7

MRID No.: N/A	40 CFR:  180.579



REVIEWER:	Donna S. Davis, Chemist

		Alexandra LaMay, Biologist

		Risk Assessment Branch VII

Health Effects Division (7509P)

THROUGH:	Michael S. Metzger, Chief

Risk Assessment Branch VII

Health Effects Division (7509P)

To:		Susan Stanton

		Barbara Madden, Minor Use Team Leader

		Daniel Rosenblatt, Chief

		Integration Minor Use and Emergency Response Branch

		Registration Division (7505P) 

		

Attached please find an addendum to the 3/2/2009 Human Health Risk
Assessment for the foliar fungicide, fenamidone.  Background

Subsequent to completion of the human health risk assessment entitled
Fenamidone.  Human Health Risk Assessment to Support Section 3 Proposals
to Add New Uses on the Root Vegetable Subgroup 1B (except radish), Okra,
Turnip Greens, Cilantro Leaves, Grapes Grown East of the Rocky Mountains
and Rotational Crop Uses for Field Corn, Sweet Corn and Soybeans.
(D353909, D. Davis, 3/2/09), the registrant, Bayer CropScience, provided
additional information which impacts some of the conclusions stated in
that memorandum.  Conclusions stated here supersede conclusions from the
3/2/09 memorandum.

Bayer CropScience (BCS) provided input to the Agency in the form of
written correspondence dated April 25, 2009 from Robyn Kneen,
Registration Manger, BCS to Rosemary Kearns, EPA.  In addition, members
of BCS met with Agency representatives on June 11, 2009 and provided
additional information for consideration.  

The Agency has reviewed additional information provided by BCS with
respect to residue chemistry data issues and has updated the previously
generated residue chemistry chapters (D366172, D. Davis, 6/16/09).  In
summary, the Agency concluded that provided the registrant is willing to
amend the proposed label to specify that the use of fenamidone on
turnips is “not for use on forage turnips grown for livestock feed”,
there is no longer an impediment to the establishment of a tolerance for
residues of fenamidone on “turnip, greens” at 55 ppm under 40 CFR
180.579.  Additionally, the Agency concurred that revision of the
proposed rotational crop tolerances is appropriate and recommended that
the following tolerances be established:

Corn, field,
grain…………………………………………………………
…..0.02 ppm

Corn, sweet, kernel plus cob with husks
removed.…………………….……..0.02 ppm

Corn, sweet,
forage…………………………………………………………
...0.15 ppm

Corn, field,
forage…………………………………………………………
…0.25 ppm

Corn, sweet,
stover…………………………………………………………
…0.20 ppm

Corn, field,
stover…………………………………………………………
….0.40 ppm

Soybean,
seed…………………………………………………………
……...0.02 ppm

Soybean,
forage…………………………………………………………
…....0.15 ppm

Soybean,
hay……………………………………………………………
……0.25 ppm

Updated Human Health Risk Assessment Conclusions

Conditional Data Requirement

The Agency previously required the registrant to submit an abbreviated
DNT in the Sprague Dawley rat with measurements of brain weight and
brain morphometric data to confirm findings in the full DNT conducted in
the Wistar rat as a condition of registration.  Subsequent to this
requirement, at the meeting of June 11, 2009, BCS provided additional
information on the Wistar rat DNT.  The registrant provided an analysis
of the brain weight data which addressed the Agency’s concerns
relative to dose difference, exposure duration and strain differences.  
Consequently, additional DNT data are no longer required for fenamidone.

Updated Human Health Risk Assessment

As a result of the BCS submission, HED is recommending that a tolerance
be established for turnip greens and that revised rotational crop
tolerances are established.  The previous dietary risk assessment
included residues of fenamidone on turnip greens at 55 ppm and included
residues for the subject rotational crop tolerances that are higher than
what is currently being recommended.  Consequently, a revised risk
assessment is not required.  Calculated risks would be equivalent to or
lower than the acceptable risks previously reported in the HED 3/2/09
Fenamidone Human Health Risk Assessment.  

Updated Regulatory Recommendation

The following updated regulatory recommendation is appropriate for
fenamidone.

Provided the data needs summarized below are addressed, there are no
human health risks of concern that would preclude the establishment of
the following tolerances:  

Under 40 CFR §180.579 for residues of fenamidone:

Vegetable, root, except sugar beet, subgroup 1B, except
radish……....0.15 ppm

Okra…………………………………………………………
………..…3.5 ppm

Cilantro,
leaves………………………………………………………..
…60 ppm

Grapes (East of the Rocky Mountains
Only)…………………..…..……1.0 ppm

Turnip,
greens…………………………………………………………
…55 ppm

Note to RD:  The recommended tolerance of 0.15 ppm on crop subgroup 1B,
excluding radishes will cover residues of fenamidone in/on carrots. 
Since a separate carrot tolerance is no longer required, it can be
removed from the 40CFR §180. 579.  An import tolerance is currently
established for residues of fenamidone on grapes and is listed in the 40
CFR 180.579 as “grapes (imported)” at 1.0 ppm.  HED recommends that
the 40 CFR 180.579 be modified to delete “(imported)” and to add a
footnote to the grape stating that the grape tolerance is applicable
only to grapes grown east of the Rocky Mountains.

Under 40 CFR 180.579(d) for residues of fenamidone and its metabolite
RPA 717879:

Corn, field,
grain…………………………………………………………
…..0.02 ppm

Corn, sweet, kernel plus cob with husks
removed.…………………….……..0.02 ppm

Corn, sweet,
forage…………………………………………………………
...0.15 ppm

Corn, field,
forage…………………………………………………………
…0.25 ppm

Corn, sweet,
stover…………………………………………………………
…0.20 ppm

Corn, field,
stover…………………………………………………………
….0.40 ppm

Soybean,
seed…………………………………………………………
……...0.02 ppm

Soybean,
forage…………………………………………………………
…....0.15 ppm

Soybean,
hay……………………………………………………………
……0.25 ppm

Prior to a favorable recommendation, HED requests the following:

The proposed Reason® 500 SC Reason label should be amended to state the
following restriction:  “Not for use on forage turnips grown for
livestock feed.”   

The petitioners should submit revised section Fs reflecting the
commodity definitions and levels shown above.  

As the following data are considered confirmatory in nature, HED
requests that this data gap be addressed as a condition of registration.

While no evidence of immunotoxicity was seen in the fenamidone database,
as specified in the new 40 CFR Part 158 data requirements, an
immunotoxicity study on fenamidone should be conducted.  

Fenamidone Addendum to 3/2/2009 Human Health Risk Assessment

Page   PAGE  3  of   NUMPAGES  4 

Page   PAGE  1  of   NUMPAGES  4 

 

