Fenbuconazole - Registration of Indar 75 WSP Fungicide 2/96
New York State Department of Environmental Conservation
Division of Solid & Hazardous Materials
50 Wolf Road, Albany, New York 12233-7250
Phone 518-457-6934 FAX 518 457-0629
February 16, 1996
Mr. James D. Davis
State Regulatory Affairs Manager
Agricultural Chemicals Registration
and Regulatory Affairs Department
Rohm and Haas Company
100 Independence Mall West
Philadelphia, PA 19106-2399
Dear Mr. Davis:
Re: Registration of Indar 75 WSP Fungicide
(EPA Reg. No. 707-239) containing the
New Active Ingredient Fenbuconazole
The New York State Department of Environmental Conservation (NYSDEC) has
accepted your application to register the pesticide product Indar 75 WSP
Fungicide (EPA Reg. No. 707-239) containing the new active ingredient
fenbuconazole. Indar is approved for use in control of blossom blight
and fruit brown rot on apricots, cherries, peaches, and nectarines and
for other diseases found on the label.
Indar WSP is applied to fruit by ground or air at a rate of 0.094 lb
active ingredient per acre (ai/acre). A maximum of eight applications
throughout the growing season will result in 0.75 lbs ai/acre/season.
The data package for this product was reviewed by the NYSDEC Division of
Fish & Wildlife (DF&W), our Geotechnical Support Section (GTS), and the
New York State Department of Health (NYSDOH).
The DF&W Bureau of Environmental Protection (BEP) determined that Indar
WSP is not toxic to the fish and wildlife of New York State.
The NYSDOH stated in their review that fenbuconazole is oncogenic in
rats and mice. The United States Environmental Protection Agency
(USEPA) classified fenbuconazole as a Group C (possible human)
carcinogen, based on the tumors in rodents and the structural
correlation with other triazole pesticides which also are carcinogenic.
The USEPA recommended that the rodent carcinogenicity data be
extrapolated for use in quantifying human cancer risks.
The USEPA calculated Theoretical Maximum Residue Contributions for
dietary exposure of the general population and for the most highly
exposed subgroup (non-nursing infants less than one year old). Based on
these calculated exposures, increased lifetime cancer risks for the
general population exceeded a one-in-a-million risk level.
Consequently, as a condition of federal registration, the registrant is
required to limit production of Indar 75 WSP for the three-year period
of conditional registration. With this restriction, and assuming that
treated crops contain tolerance level residues, estimated lifetime
cancer risks for the general population are below the one-in-a-million
cancer risk level.
There are no chemical-specific federal or New York State drinking water
standards for fenbuconazole. Based on the cancer potency slope factor
(0.0106 (mg/kg/day)-1) and the 6 NYCRR Part 702.4 procedures for
deriving ambient water quality standards and guidelines based on
oncogenic effects, the ambient water quality value associated with a
one-in-a-million increased lifetime cancer risk is 3.3 ug/L. Given the
incidence of thyroid tumors in two chronic rat studies, the
uncertainties of the mechanism for thyroid tumor development in these
studies, the liver tumors in mice and the oncogenic potential of other
triazole pesticides, the value of 3.3 ug/L should be considered a
potential State drinking water standard and groundwater standard.
Fenbuconazole was oncogenic in laboratory animals. Careful
consideration by this Department must be given to registering products
that are oncogenic and used on food crops, given the potential for
exposure. Considering the conditions of federal registration, we
contend the risks to the general public from use of Indar 75 WSP on the
labelled food crops are low. However, any increase in the use of Indar
in the future may be cause for concern from increased exposure of the
general population to fenbuconazole and the oncogenic risks it poses.
The GTS stated in their review that the labelled use of Indar 75 WSP
should not cause a groundwater impact in New York State when used
according to label directions.
After consideration of the reviews by NYSDOH, DF&W, and the GTS, our
Pesticide Product Registration staff contacted Dr. Wayne Wilcox of
Cornell University who has concentrated on stone fruits, grapes and
berries in his studies. Dr. Wilcox has worked with fenbuconazole and
sees a need for this product because of the growth in drug resistant
strains of the target fungi. Based on this and the technical reviews,
we accept for registration the pesticide product Indar 75 WSP Fungicide
(EPA Reg. No. 707-239) for use in New York State. As a condition of
this registration, Rohm & Haas Company is required to notify the
Department of any changes in use pattern and crop residues that are
expected to result when the federal conditions of registration expire so
that potential exposure and risks can be reevaluated.
Enclosed for your records are the stamped "ACCEPTED" label and the
certificate of registration for Indar 75 WSP (EPA Reg. No. 707-239).
If you have any questions on this matter, please contact Maureen
Serafini, Supervisor of our Pesticide Product Registration Section, at
Norman H. Nosenchuck, P.E.
Division of Solid & Hazardous Materials
cc: w/enc. - D. Rutz/W. Smith, Cornell University
N. Rudgers, NYS Dept. of Ag. & Mkts.
N. Kim/A. Grey, NYS Dept. of Health
J. Leach, NYS Dept. of Health