Alex Alton Thomas

Alex Alton Thomas

Speaker | University of Wisconsin - Stevens Point and Compost Manufacturer's Alliance

Stevens Point, WIS | Alex.thomas@uwsp.edu

A Wisconsin native, Alex completed his undergraduate degrees in Biology and Waste Resources before working on waste planning efforts in Eastern Washington. Alex now works as a Graduate Research Assistant at the University of Wisconsin – Stevens Point under the Soils and Waste Resources department, researching the effects composting can have on infectious diseases like Chronic Wasting Disease and E. coli. Alex is also the Field Supervisor for the Compost Manufacturing Alliance and a part-time organics operator for the Marathon County Solid Waste Department.

Session Code: 4C

Track: CREF Research

Session Name: Aeration Impacts; Prions; ROI Study

Session Time: Wednesday, January 26, 8:30 AM to 10:00 AM

Presentation Title: Chronic Wasting Disease Composting: Composting Infectious Proteins

Presentation Description: Chronic Wasting Disease (CWD) is a transmissible spongiform encephalopathy (TSE) that has been detected in cervid (e.g. deer, elk, moose) populations across the United States, Canada, Scandinavia, and South Korea. CWD, like other TSEs, is a progressively degenerative neurological disease caused by a misfolded protein known as a prion. The course of the disease consists of abnormal behavior, emaciation, and ultimately death. Prions are extremely persistent in the environment, including in soils . Additionally, prions also remain infectious when bound to soil particles, survive many chemical treatments, and can be taken up through the vascular systems of plants. In Wisconsin, disposal of CWD-positive hunter-harvested deer is the responsibility of the Wisconsin Department of Natural Resources (WDNR). Of the licensed landfills in Wisconsin, only 12 will accept CWD-positive carcasses, limiting disposal options for infected materials and increasing costs for proper disposal. Increasing regulations on disposal, meant to limit CWD spread, have further increased cost and time for landfills and has highlighted the need for alternative disposal methods. Composting has been shown to be effective at reducing recalcitrant organic contaminants and is a common waste disposal method for animal carcasses. The high microbial activity and temperatures achieved during composting raises the possibility that this method could deactivate infectious CWD prions. Previous studies suggest that composting may have some efficacy in this regard, but this has yet to be demonstrated using whole tissues. In this study we are investigating the effectiveness of composting for inactivation of CWD prions using whole and butchered carcasses. If successful, these methods will provide much needed relief to agencies seeking alternative means of CWD infected waste disposal. Preliminary data from two experiments will be presented regarding the composting process, media nutrient contents, and CWD prion presence/absence. This project includes increased microbial analysis thanks to the Compost Research Education Foundation.