Renewed ruckus on rBST

WASHINGTON - An anti-biotechnology group filed a Citizen Petition last week seeking to have FDA overturn its 1993 decision to approve use of Posilac, Monsanto Co.'s recombinant bovine somatotrophin (rBST), to stimulate milk production in dairy cows. The petition, filed by the Center for Food Safety (CFS), is based on a leaked report by a government committee in Canada, which has been reviewing rBST for nine years.

The principal contention in the Citizen Petition involves a Monsanto-sponsored study in which laboratory rats fed high doses of rBST were found to absorb the substance, developing an antibody response, cysts in the thyroid and increased infiltration of rBST into the prostate. CFS claims that although FDA officials cited the study in a 1990 paper, which included a statement that rBST is not orally active in rats, the agency was not actually aware of the results of the study...