About one in 5 chickens and one in 10 eggs in Britain contain traces of drugs that may cause cancer, birth defects or heart attacks, according to The Soil Association, a group that promotes organic farming.

Richard Young, coordinator of the association?s campaign against the overuse of antibiotics in intensive farming, said that drugs used to control intestinal parasites in poultry posed the most serious threat. ?Despite repeated assertions by regulators that nearly all poultry products are free from detectable residues, figures clearly show that about 20 percent of chicken meat and 10 percent of the eggs tested contain residues of drugs deemed too dangerous for use in human medicine,? he says.
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