Hormones: here's the beef: environmental concerns reemerge over steroids given to livestock - animal excretions release synthetic hormones into environment - Statistical Data Included

Science News, Jan 5, 2002 by Janet Raloff

Inducing these turtles to become "superfemales" could prove harmful, she worries, if they divert unhealthy amounts of energy into egg production.

One of Oberdorster's students, Lisa K. Irwin, found that the ponds' enrichment with bovine estrogen also prompted juvenile sunfish to make egg-yolk protein--even though these males and females were all well below an age when even females normally do so.

With a European ban on the use of steroid drugs in livestock, why does the EU fund studies on environmental impacts of such use? One answer comes from data amassed by Rainer Stephany of the National Institute of Public Health and the Environment in Bilthoven, the Netherlands.

Though Europe's beef industry maintains that no steroids are used, Stephany says that his lab and others have demonstrated by analyzing meat samples that the continent hosts an "illegal--black market--use of growth promoters."

A "defensible overall estimate for the use of these compounds in the European Union, based on results from annual regulatory residue-testing programs, could be in the range of 5 to 15 percent" of beef cattle, he reported in the proceedings of the Copenhagen conference, published last summer as a special, 571-page issue of APMIS (formerly ACTA PATHOLOGICA, MICROBIOLOGICA ET IMMUNOLOGICA SCANDINAVICA).

Moreover, he notes, because all such drug treatment in Europe is illegal, illicit users tend to employ whatever is available and affordable. Residues of at least 35 such drugs have been found in meat samples. This complicates screening, Stephany observes, since an investigator never knows quite what to look for and each assay can cost as much as a cow's entire carcass is worth. This situation contrasts sharply with that in the United States, where drug residues in meat invariably consist of one or more of only six FDA-approved growth promoters, he says.

Though the EU is clearly concerned about the impacts of livestock steroids, what about U.S. regulators? At the Copenhagen meeting, Stephen F. Sundlof, director of FDA's Center for Veterinary Medicine in Rockville, Md., noted that although "it is my role to regulate these substances ... I was only made aware at this workshop that we may be having some environmental issues to consider."

That was nearly 2 years ago. In the interim, Soto and Guillette have briefed Sundlof on their studies. Sundlof has also learned of the German findings. From these, he now concludes that the environmental fate of livestock-steroid use "is something that we [at FDA] are definitely concerned about."

"My sense," he told SCIENCE NEWS, "is that right now [FDA is] going to be looking into the whole issue of pharmaceuticals getting into water--and that's not just steroids, but it's also antibiotics and some other potent chemicals."

If soon-to-be-published analyses of stream-sampling data by the U.S. Geological Survey confirm that livestock drugs are getting into the environment, Sundlof says, new regulations may be called for. He doesn't envision a phase-out of livestock steroids, but he says that farmers might be asked to assume greater diligence in managing the animals' wastes.