Animal antibiotics found in water supply

Cattle ranchers generally don't like to think about the environmental impact of their ranching practices, but as a society, we need to start looking more closely. You can't dose tens of millions of cattle with antibiotic drugs and have a clean water supply, too. Especially if you live anywhere near Greeley, Colorado, the beef (and slaughterhouse) capital of the western world.

• A Colorado State University study is the first to show that antibiotic drugs used specifically for enhancing growth, preventing diseases and increasing feed efficiency in food animals, such as cattle, are making their way into public waterways.
• The study, which identifies antibiotics in waterways that come from both human and animal uses, is the first to pinpoint drugs specifically from animal sources.
• For example, the antibiotic monensin, used exclusively in agricultural applications for growth enhancement in cattle, is used as a marker in the study and was measured only in waterways located near animal feeding operations.
• The study also is among the first to measure the compounds in stream and river bed sediment and found that the concentration of antibiotics was 20 times to 1,000 times greater in sediment than in the surrounding water.
• According to a separate collaborative Federal Drug Administration and Colorado State College of Veterinary Medicine and Biomedical Sciences environmental assessment for the use of monensin in the feed of beef cattle, these levels are below concentrations that could result in environmental impact or effects on human health.
• The antibiotic study's authors also point out that the results do not necessarily implicate waste management practices of animal feeding operations, but rather reveal that animal antibiotics are making their way into streams and rivers.
• The presence of pharmaceutical compounds in urban wastewater discharge also is recognized as an important issue and is being studied by researchers across the country.
• As a result of the study's findings, the Colorado State group is beginning to work with the agricultural community to identify best management practices at agricultural operations, such as waste handling that will minimize the release of these compounds to the environment and contribute to sustainable agricultural practices in the future.
• "The most important question that needs to be addressed relates to the occurrence and source, either urban or agriculture, of these compounds," said Jessica Davis, professor of soil and crop sciences and co-principal investigator of the project.