On organic farms only sick birds are given antibiotics

The Soil Association has accused the food producers of flouting EU laws and is urging the government to take action.

The companies say they are using the antibiotics, which are due to be made illegal in the UK in 2006, to protect flocks from disease rather than to plump them up.

But the association, which is known as a standard bearer for organic food, said the drugs could affect human health.

Richard Young, the association's policy advisor, told BBC Radio 4's Today programme: "They're being banned because there are concerns about them compromising the effectiveness of antibiotics which are under development for treating hospital superbugs.

'Disease control'

"There are serious concerns that drugs which doctors will be relying on in four to five years' time may not work when introduced.

"What we are saying to the government is that European legislation which affects this area does not allow the use of these drugs for disease control."

Mr Young said the Secretary of State for Environment, Food and Rural Affairs Margaret Beckett had told the association in a letter that she would take action.

"The overall use of drugs in intensive livestock production has gone up rather than down so we think the government has got some serious rethinking to do," he said.

It's only 20% of producers who are using them and they're not necessarily using them on all their birds Peter Bradnock British Poultry Council

The British Poultry Council, which promotes the industry's interests, admitted one in five producers were using the growth-promoting drugs.

But it said there has actually been a slight reduction in the use when the latest figures are compared with those from three years ago.

Chief Executive Peter Bradnock told BBC News Online: "I believe the industry is using these antibiotics in a responsible way.

"It's only 20% of producers who are using them and they're not necessarily using them on all their birds.

"Under the current standards, the producers are required to take the advice of a responsible vet and all they are doing is following that advice."

Mr Bradnock said the antibiotics are usually mixed into the chicken's feed.

He rejected claims that the way in which the growth promoters were being used amounted to a breach of EU law.

And he said he accepted the veterinary medicine licensing authorities had concerns about the antibiotics, but insisted that imposing a total ban now would do more harm than good.

"We are talking about products which are currently licensed and which are being used in certain circumstances in the interests of the bird, not across the whole industry.

"Where bans have been imposed in other countries, there has usually been a big increase in the use of other types of antibiotics which are much closer to those used in human medicine.