Companies in North America want to spray crops with a bacterium that might cause a deadly lung infection in people with cystic fibrosis. Experts on the bacterium, Burkholderia cepacia, are calling for a ban on its use in pest control until it is proved safe.

Good Bugs of Madison, a spin-off from the University of Wisconsin, hopes that the bacterium will outcompete fungi that can grow on peas, maize and potatoes, keeping the plants free from infection.

But B. cepacia can cause a severe and incurable lung infection in people with cystic fibrosis. The US Environmental Protection Agency (EPA) is blocking an application for large-scale testing filed last year by Good Bugs until the company provides more evidence that its strain of B. cepacia represents no threat to human health. Phil Hutton, head of the EPA's microbial branch in Washington DC, says: "We have not yet received information we feel is adequate to make that judgment."

The EPA, together with the Canadian Pest Management Regulatory Authority, is also reviewing a similar application by another company, Agrium of Calgary, Alberta. And Jonathan Barry, president of Good Bugs, told New Scientist he was confident that he could gain permission to test the bacterial spray in Britain.

Barry believes the strain of B. cepacia used by Good Bugs, isolated from soil, is quite safe. But that doesn't reassure Robert Beall, president of the US Cystic Fibrosis Foundation. "We don't think it should be used in any agricultural setting until we know what's safe and what's not. We don't know yet if there are any truly nonpathogenic forms of this organism."

There may be none. "Molecular genetic evidence indicates there might be a threat to health regardless of which strains are selected," says Alison Holmes of Imperial College School of Medicine in London.

In a paper to appear in Emerging Infectious Diseases, Holmes, John Govan of the University of
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Contact: Claire Bowles
claire.bowles@rbi.co.uk
41 (0)1 71 331-2772
New Scientist
20-May-1998