Regulatory aspects of fluoride toxicity

The polybrominated biphenyl (PBB) contamination incident that occurred in Michigan from 1973 to 1978 brought about an acute consciousness of dairy herd health. At the insistence of owners with assumed low level PBB health complaints and problems, an intensive examination was made of their herds. One of the distinct problems emerging from these team investigations was chronic fluorosis. The discovery of this problem led to state regulations limiting fluorine contentin feeds. The resulting restrictions on this element in Michigan are the most stringent in the United States.