Ethiprole Photoproducts and Metabolites
J. Agric. Food Chem., Vol. 51, No. 24, 2003 7061
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persistent than fipronil (7, 8). The acceptable daily intake is set
about 7-fold lower for the photoproduct F-CF3 as compared
with fipronil (4, 31). Thus, ethiprole circumvents a question
brought up for fipronil (7) of the potential toxicity of a
photoproduct not formed as a metabolite. These are favorable
properties for ethiprole in model systems possibly applicable
to actual use conditions.
ABBREVIATIONS USED
[3H]EBOB, 4-n-[2,3-3H2]propyl-4′-ethynylbicycloorthoben-
zoate; E-SOC2H5, ethiprole; F-SOCF3, fipronil; GABA,
γ-aminobutyric acid; IC50, concentration for 50% inhibition; PB,
piperonyl butoxide; tR, retention time.
ACKNOWLEDGMENT
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We thank our laboratory colleagues Ligong Chen, Gary Quistad,
and Motohiro Tomizawa for helpful suggestions. We especially
thank Professor Paolo Cabras of the University of Cagliari, Italy,
for advice and arrangements in initiating this research.
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Received for review June 13, 2003. Revised manuscript received August
15, 2003. Accepted September 2, 2003. The project described was
supported by grant R01 ES08419 from the National Institute of
Environmental Health Sciences (NIEHS), NIH, and its contents are
solely the responsibility of the authors and do not represent the official
views of NIEHS, NIH.
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