Friends of the Earth environmental group has asked US Agriculture Secretary Ann Veneman to withdraw a biotech corn suspected of containing a toxic mould from the market.

The group wants the corn withdrawn while it is tested for the mould, after an Iowa farmer reported that the corn may have caused infertility in some members of his hog herd. Friends of the Earth is concerned that harmful corn may enter the food chain.

Jerry Rosman, who operates Rolling R Farms in Iowa, reported that the reproductivity of his hog herd fell from 90% to 20% between October and August 2001. He alerted the Agriculture Department after discovering that four of his neighbours had had similar problems. Following the publicity surrounding Rosman’s case, several Midwestern farmers and veterinarians have come forward with similar reports.

The corn, produced by Garst Seed, is known as Bt corn and is genetically engineered to resist moulds. Initial tests have found that the corn contains the fusarium toxin that is harmful to animals and humans. The Agriculture Research Service has said that a chemical compound may be to blame for the toxin’s presence, however.

Garst Seed remains positive that its corn is not to blame: “We are confident that corn seed has not caused the problems he has experienced,” company spokesman Jeff Lacina said in a statement quoted by Reuters. “The hybrids that Mr. Rosman purchased have been widely grown for several years and no one else who has grown them has reported similar experiences to us.”

The FDA is reported to be looking into the problem.