Benzene hexachloride poisoning in cattle.

Of 174 cattle dipped in an emulsified preparation of benzene hexachloride labeled for plant use, 18 were fatally poisoned. The preparation contained 0.14% active ingredient, gamma isomer of benzene hexachloride (BHC), a normally safe concentration for cattle. Analyses revealed 0.08% gamma BHC in the used dip and 0.5, 7.9, and 198 ppm in liver, kidney, and hairskin specimens, respectively, from a fatally affected cow. Microscopic examination of the freshly prepared dip demonstrated emulsion droplets ranging from 5 to 60 mu in diameter.