Officials are examining Ames’ water supply to determine if unsafe levels of waste are present.

A panel of university experts and city officials convened to examine concerns about animal waste handling at the National Animal Disease Center.

The concerns addressed the disposal of animal waste that may contain prions, irregularly shaped proteins that are responsible for degenerative nervous system diseases such as bovine spongiform encephalopathy – “mad cow” disease – scrapie, chronic wasting disease in deer and Creutzfeldt-Jakob disease in humans.

The prions, usually contracted after the ingestion of infected brain and spinal tissue, cause brain tissue to wear away, leaving spongelike holes and resulting in symptoms of deteriorated muscle control, loss of balance, dementia and eventually death.

“There was an initial letter from two employees which raised concerns,” said Thomas Neumann, director of Ames Water and Pollution Control.

Neumann said the two NADC employees, Richard Auwerda and Timothy Gogerty, noticed differences in animal handling protocol between the NADC and the nearby National Veterinary Services Laboratories facility. Both facilities are overseen by the U.S. Department of Agriculture, but report to different branches of the department, and both are involved with the study of diseases that involve prions.

Neumann said everyday animal husbandry waste, such as feces and urine, is collected by drains in animal containment areas and heat-treated on site before being sent to the Ames wastewater treatment plant. Other waste, such as the animal carcasses themselves, is disposed of after a two-stage incineration on NADC grounds.

“The drains from the animal areas go into holding tanks, which are heated at 250 degrees Fahrenheit for 30 minutes,” said Sandy Miller Hays, spokesperson for the Agricultural Research Service, the branch of the USDA that runs the NADC. “One minute at this temperature kills 99.9999 percent of infectious material.”

Hays said after death, animal carcasses are first incinerated at 1,400 degrees. The resulting ash is again burned at 1,800 degrees before disposal.

Hays said the main differences between the NADC and NVSL policies resulted from the different ventilation systems in the buildings. These variations cause the facilities to employ different animal care protocol.

“Things are done differently because the buildings are different,” Hays said. “Both methods are valid.”

A panel was assembled to specifically examine whether the on-site waste handling and treatment is effective and appropriate for containing and destroying the potentially deadly prions from entering the water system. Members of the panel include university researchers, city officials and federal research personnel.

James Colbert, associate professor of ecology, evolution and organismal biology, said he was asked to be on the panel because of his status as a biology researcher, water quality advocate and local citizen.

“I’m very impressed with the background and knowledge of the experts on the panel,” Colbert said. “This is getting very serious attention from very capable people.”