About the editors Lester V. Cralley was formerly manager of Environmental Health Services for Aluminum Company of America. He has served as president of the American Industrial Hygiene Association and vice chairman of the American Board of Industrial Hygiene. He is a Diplomate of the American Academy of Industrial Hygiene, an honorary member of the American Industrial Hygiene Association, and a recipient of the Cummings Memorial Award. He received his PhD in industrial hygiene from the University of Iowa. Lewis J. Cralley was formerly associated with the National Institute for Occupational Safety and Health, Public Health Service. He has served as president of the American Industrial Hygiene Association, chairman of the American Conference of Industrial Hygienists, and chairman of the Occupational Health Section of the American Public Health Association. He was a recipient of the Meritorious Service Award for Public Health Service, Department of Health, Education, and Welfare, the Henry F. Smyth Award, and the Cummings Memorial Award. He received his PhD in industrial hygiene from the University of Iowa. W. Clark Cooper has served as a consultant in occupational health from 1972 to the present. He has been on the faculty of the Dept. of Occupational Health, School of Public Health, University of California, Berkeley. He was Director of Occupational Health Field Headquarters in Cincinnati, eventually becoming Chief of Division Headquarters in Washington, D.C. He was also Deputy Chief of Medicine, U.S. Public Health Service Hospital in San Francisco. He also worked at the National Institutes of Health, testing new antimalarial drugs. He has also been a research fellow in nutrition at the University of Cincinnati, conducting studies on nicotinic acid and pellagra. Dr. Cooper received his MD from the University of Virginia and MPH from Harvard University.