Within a year after Muller and his group persuaded the NAS to accept the linear model for gonadal mutations, the practice was extrapolated to somatic cells and cancer. Twenty years later, NAS adopted the linear approach for chemicals. Soon thereafter, the U.S. Environmental Protection Agency announced it would use the linear model for risk assessment, Calabrese points out.
Some can accept that even the most distinguished scientists have human failings, he acknowledges. But his view is that "the regulatory research community needs to hear about this. The implications of my findings are that we should revisit our exposure regulations because our regulatory history is founded on a deception. We have seen literally hundreds of thousands of cleanup decisions based on a model that was fraudulently derived. I think we should probably have drastically different exposure standards today, and far less fear."
Calabrese believes, "The die was cast by Muller and regulations adopted since then have gone unchallenged. I think he got his beliefs and his science confused, and he couldn't admit that the science was unresolved. So he went ahead and expressed an opinion about how to handle the public health situation."
Geneticists in the 1950s came to embrace the "linear dose-response model" of risk because at the high exposures they tested, there was no level below which DNA damage did not occur. They felt medical doctors didn't grasp how significant were the dangers. As the smartest and brightest, Muller anticipated the risk of atmospheric atomic testing and became passionately committed to protecting society, Calabrese explains.
Muller and Curt Stern had done many of the key experiments. Muller himself served on the NAS's Biological Effects of Atomic Radiation (BEAR) committee, through which the linear dose-response approach to risk assessment became firmly en
|Contact: Janet Lathrop|
University of Massachusetts at Amherst