Lead poisoning in cattle and its implications for food safety.

The lead poisoning incidents in cattle investigated by the Veterinary Laboratories Agency between 1990 and 2003 are reviewed. Lead poisoning was most commonly encountered in young calves, but cattle of all ages were affected. The lead was derived mainly from lead paint, lead accumulator batteries and lead in soil from old mine workings. Paint was responsible for the majority of cases of poisoning in young calves; yearling animals were most at risk from discarded batteries, and adult cows were most commonly poisoned by geochemical sources of lead. There was a marked seasonal incidence, with most cases occurring after turnout in the spring and early summer.