Abstract: | Milk, hay and silage produced in orchard and non-orchard areas have been analysed for their content of chlorinated pesticides. The residue levels in milk produced in orchard areas were about double those in milk produced in non-orchard areas. The levels in hay were much higher (30% up to sevenfold) in the hay produced in orchard areas and the levels in silage from the two areas showed small differences. Milk collected after cattle had been grazing in an orchard for 3 to 4 days contained 10% more pp′-DDT and 2-, 3-, 7- and 15-fold morepp′-DDE, pp′-TDE and heptachlor epoxide, gamma-BHC and pp′-TDE olefin 1-chloro-2,2-bis(p-chlorophenyl)ethylene], respectively, than did the samples collected one day before the cattle grazed in the orchard. |