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December 7, 2006

ellen silbergeld

Dr. Ellen Silbergeld

Big Farms, Big Health Risks

Panel Addresses the Public Health Costs of Industrial Animal Production

As industrial animal farming escalates on a global scale, Bloomberg School researchers with the Center for a Livable Future and other experts are warning of serious health and environmental impacts associated with the practice.

At a December 6 symposium to mark the CLF’s tenth anniversary, the scientists voiced concerns about worker safety and waste disposal and the excessive use of antibiotics in animal feed.

“The Center for a Livable Future (CLF) approach is, ‘Why do we have this problem and how do we stop it when it comes to our dinner plate?’” said Environmental Health Sciences professor Ellen Silbergeld, PhD, noting that an understanding of the social and economic factors of industrial animal production is equally important as the scientific aspects.

“Many of these problems originate in the management and operation of animal farms,” said Silbergeld, who studies the health and environmental risks of large-scale farming. “The decisions and control of these farms are in the hands of the food producers who have dominated industrial food animal production in the United States. They control animal breeding, feeds and feed additives, housing conditions, processing plants and wholesale markets.”

The center’s day-long symposium?Charting a Course to Sustainability Through Research, Education and Service?highlighted CLF-funded research, including studies on parasite contamination in the Chesapeake Bay, nutritional transition in China and overused household biocides.

“That work has served as a catalyst for collaborations, the evolution of impactful knowledge and the opportunity to contribute in areas that have not always been in the purview of public health,” Silbergeld said. 

Symposium panelist Lance Price, PhD '06, MS, whose work focuses on assessing the health risks associated with antibiotic use in industrial animal farming, said the practice has played a role in the dramatic rise of drug-resistant bacterial infections over the past 15 years.

“We really need to see food animal production as a source of antibiotic-resistant bacteria,” said Price, who worked on a study of poultry employees on the Eastern Shore that found workers are 32 times more likely to carry E.coli resistant to gentimicin, the most commonly used antimicrobial on poultry farms.

“Why are our lifesaving antibiotics being used in animal production?” asked Price, who said he would like to see a moratorium on the approval of new antibiotics and a ban or restriction on the use of gentimicin.

Keeve Nachman, PhD '06, MHS, a scientist with the U.S. Environmental Protection Agency, discussed the use of arsenic in poultry feed as a growth stimulator, a practice that has been in use since the 1940s. Annually, domestic poultry production introduces 300,000 kilograms of arsenic into the environment, primarily through poultry house waste.

Consumption of poultry and contamination of groundwater and soil from poultry waste are potential human exposure routes for arsenic, a human carcinogen that is strongly associated with skin and lung cancer.

Nachman, who said that responsibility for regulatory oversight of poultry house waste is unclear, supports regulation by the U.S. Food and Drug Administration. He said the ideal solution, adopted by the European Union, is a ban on the arsenic-containing drug Roxarsone in animal production. —Jackie Powder

Public Affairs media contacts for the Johns Hopkins Bloomberg School of Public Health: Kenna Lowe or Tim Parsons at 410-955-6878 or