Metabolism and disposition of diphacinone in rats and mice.

14C-diphacinone (0.2-1.5 mg/kg) was orally administered to rats and mice. Residue distribution in various tissues and radiocarbon elimination in feces and urine were determined. More than 60% of the administered radiocarbon was eliminated in feces and about 10% in urine in 4 days from mice and in 8 days from rats. The greatest amount of radioactivity in tissues of both rats and mice appeared in liver. Brain, muscle, blood, and fat had the lowest residue levels. Metabolites in feces and liver were chromatographically isolated and identified by mass spectrometry. In addition to unchanged diphacinone, four hydroxylated metabolites were identified in feces and liver. Hydroxylation occurred on either or both the indandione or phenyl rings. The positions of the hydroxy groups on the rings were not established.

Exposure of pesticide applicators and support personnel to O-ethyl O-(4-nitrophenyl) phenylphosphonothioate (EPN).

Applicator personnel were monitored during aerial and ground applications of EPN to cotton in Mississippi and Arizona. Respiratory exposure based on an 8-hr workday averaged 11 micrograms for pilots,, 15 micrograms for loaders, and 39 micrograms for ground applicators. Respiratory exposure of flagmen, monitored during a complete application cycle, averaged 317 micrograms/8 hr. Mean 8-hr dermal exposures were 2.1 mg for pilots, 6.3 mg for loaders, 117.7 mg for flagmen, and 7.5 mg for ground applicators. The levels of exposure were affected by route of exposure, body region, method of application, job function, attitude and experience, duration of exposure, weather conditions, and accidents. Recommendations are made to reduce the exposure of pilots, loaders, and ground applicators by modification of procedures and use of personal protective equipment. Because flagmen had the greatest exposure, a recommendation is made to substitute their function with fixed landmarks; if this is not possible, flagmen must wear the proper protective equipment.