Mirex kinetics in chickens.

Mirex kinetics were determined in chickens after a single dose of 30 mg/kg iv or 300 mg/kg orally. The decline in blood concentrations was biphasic and suggested uptake of mirex by "fast" and "slow" tissue compartments, with the greatest accumulation in fat and skin 2 wk after administration. Less than 1% of the dose was excreted in 2 wk. Mirex depletion rates in skin and fat were determined in growing chicks fed 1 or 10 ppm mirex in the diet for 1 wk. Calculated disappearance half-times for mirex were 24.8 in skin and 31.5 d in fat. The decrease in tissue concentrations was attributed to dilution in tissue mass accompanying the rapid growth rate rather than to excretion of mirex. The results do not indicate that avian species eliminate mirex more efficently than mammals.