Toward Safer Disposal Of Animals Infected With Mad Cow And Other Prion Diseases

The study is scheduled for the April 15 issue of ACS’ Environmental Science & Technology, a semi-monthly journal.

In the study, Joel A. Pedersen and colleagues from the University of Wisconsin cite the need for safe methods of disposing of prion-infected carcasses, noting that prions can resist harsh conditions such as strong disinfectants and dry-heat temperatures of 1,100°F that destroy other disease-causing agents and that prions can remain infectious in the soil for at least three years. Pedersen and colleagues investigated the effect of different conditions (pH, salinity) on the adsorption, or attachment, of prions to sand particles.

They found that prions become less firmly attached to sand particles, and thus potentially more mobile, under alkaline conditions. These conditions would be produced by lime, as well as in older landfills. In the natural environment, acidic conditions may keep prions near the soil surface, increasing the risk that animals will ingest prions and become infected, the report says. The team is conducting further research to determine whether these expectations are borne out.