No abstract

Aldrin, dieldrin, heptachlor, DDT, and methoxychlor were fed in the daily rations to dairy cows for 1 6 weeks. For varying periods afterwards, the cows were fed on insecticidefree rations. Milk samples were analyzed through both periods to determine the rate of accumulation and decline. The rates of accumulation for the various insecticides were as follows: cildrin (excreted as dieldrin) > dieldrin > DDT > heptachlor (excreted as heptachlor epoxide) > methoxychlor. CERTAIN CHLORINATED HYDROCARBON insecticides are excreted in milk at different rates per unit of intake. Many studies have contributed to the determination of their relative safety in actual usage.

of the 12-week period during which the cows were on dieldrin intake, ratios of dieldrin in fat to dieldrin in milk ranged Literature Cited(1) Claborn, . V., Wells, R. W., Agr.

No abstract

Dieldrin, fed in the diet of dairy cows at levels of 0.1, 0.25, 0.75, and 2.25 p.p.m., appeared in the milk at the end of 6 to 12 weeks at average levels of 0.02,0.06,0.11 ,and 0.28 p.p.m., respectively. Tissue analyses at the end of the feeding period indicated that dieldrin was present in fats at concentrations varying from 0.24 p.p.m. at the lowest level of feeding to 5.48 at the highest. The amounts of dieldrin found in other tissues was proportionate to their fat content.