Dr. Thomas W. Kensler is a Professor of Toxicology at Johns Hopkins University, School of Hygiene and Public Health. He has a joint appointment a the Johns Hopkins Oncology Center. He serves as a Diplomat on the American Board of Toxicology and serves on the Chemical Pathology Study Section of the National Institutes of Health. He has also been awarded the Research Center Development Award from the National Cancer Institute. There has always been conflicting opinions on the role of natural and synthetic carcinogens in the development of cancer.
Any substance can become a poison at high concentrations.
There have been many scientists who have attributed the development of cancer solely to synthetic chemicals. However, other scientists have recognized that natural substances can also be potent carcinogens. Historically, food legislation has often been enacted in response to our fear of cancer. Aflatoxins, metabolites produced by fungi, were first discovered in 1960 and their carcinogenic properties were recognized in 1963. During this period of time, there was great public sensitivity to environmental carcinogens.