Pbb Contamination on Michigan Farms, a Decision Case.

This decision case concerns the PBB (polybrominated biphenyl) contamination of Michigan feed throughout the state in 1973.  In September 1973, two Michigan farmers began noticing sick cows, decreased milk production, cows refusing to eat, animal weight loss, and other increasingly severe symptoms. Soon, other farmers reported similar problems.  Thus began Michigan’s PBB dilemma, a catastrophic situation that adversely affected numerous farms, families, and communities. The decision maker, Dr. Donald Isleib, is Chief Deputy Director of the Michigan Department of Agriculture.  The case is written in three parts to simulate the actual occurrence. The objectives of the case are (1) to enhance student understanding of the immense decisions that must be made when a disaster occurs, (2) to stress that decisions often must be made using insufficient or unavailable information, and (3) to emphasize that small mistakes can affect a large number of people.  Initially, the key issue was to identify the source of the maladies.  Subsequently, key issues were to determine safe levels of PBB contamination for animals and humans, appropriate use of contaminated animals and by-products, the disposal of dead animals, and the fate of contaminated land and facilities.  The case is suitable for use with introductory, upper level, and interdisciplinary classes, depending upon the topics to be addressed and the depth of coverage, e.g. ethics, regulatory policies, soil characteristics and their role in environmental cleanup, plant growth on polluted soil, introductory crop science, and others areas.  The Teaching Note includes instructional suggestions and additional references.