| Accession Number | 5004930 |
| Title | Effects of chlorfenapyr on adult birds |
| Project Description | Chlorfenapyr is a halogenated pyrrole insecticide that is registered for use in 31 countries. |
| Emergency exemptions have been granted by EPA for the use of chlorfenapyr on cotton in at |
| least 11 states since 1995. Chlorfenapry is persistent in soil (avg. half life of 1 yr), sediment (avg. |
| half life of 1.1 yr), and water (avg. half life of 0.8 yr); has high acute, subacute, and chronic |
| (reporductive) toxicity in birds; and poses an acute poisoning hazard to aquatic organisms. |
| Results of experiments with laboratory mice and rats revealed a number of histological |
| abnormalities, including nerve tissue degeneration. In March 2000, the EPA issued a critical |
| evaluation of chlorfenapyr that caused the manufacturer to withdraw its application for use on |
| cotton; other applications remain and the manufacturer can resubmit the cotton application. The |
| EPA action was based heavily on the results of studies of effects on birds (mallards, bobwhite, |
| red-winged blackbirds). Unfortunately, no information has been collected on biochemical or |
| histological (micropathology) endpoints, nor were any tissues analyzed for chlorfenapyr |
| metabolites. Thus, there are no biological markers available for determining exposure of birds to |
| chlorfenapyr. The objectives of this study are to describe the pathological effects of chronic |
| exposure, identify biochemical responses, and determine tissue retention potentials in mallard |
| ducks. In a preliminary feeding trial, 55 mallards will be fed diets containing either of five |
| concentrations of technical or formulation chlorfenapyr for 10 weeks. Birds that die during the |
| study, and all birds euthanized at the end of the feeding trial, will be necropsied and tissues will |
| be removed for histological examination, biochemical assessment, and chemical analysis for |
| chlorfenapyr. Results of the preliminary feeding trial will be used to determine appropriate dietary |
| concentrations, tissues, and biochemical procedures for the primary study to be conducted the |
| following year. Results of the primary study will be used to characterize tissue and biochemical |
| effects of chlorfenapyr and to establish biomarkers or a set of biological responses (criteria ) that |
| are diagnostic for exposure to chlorfenapyr. |
| Keywords | acute, agriculture, biochemistry, biomarker, chronic, histology, insecticide, mallard, pathology, |
| physiology, sublethal, toxicity, |
| Principal | Peter H Albers, USGS Patuxent Wildlife Research Center: pete_albers@usgs.gov; Mark J |
| Investigators | Melancon, USGS Patuxent Wildlife Research Center: mark_melancon@usgs.gov; George |
| Noguchi, U.S. Fish and Wildlife Service, Division of Environmental Quality: |
| george_noguchi@fws.gov; David E Green, USGS Patuxent Wildlife Research Center: |
| david_green@usgs.gov; Patrice N Klein, The Humane Society of the United States: |
| patriceklein@hotmail.com; |
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