Editor's note: This is part II in a series on the latest acrylamide and cancer scare. To read part I, click here.
The major source of bad science on the issue of acrylamide and cancer has been the Center for Science and the Public Interest and its Executive Director Michael Jacobson. As the first word came out about the presence of acrylamide in America's food a few years ago, Jacobson said that acrylamide would be expected to "significantly increase the risk of cancer in humans." He also claimed that acrylamide was responsible for "thousands of cancers" and "thousands of deaths" annually.
Indeed, in CSPI's petition to the FDA (June 4, 2003) in which it asked the agency to force food manufacturers to limit the amount of acrylamide in their products, CSPI claimed that "dietary acrylamide causes an estimated 8,900 cancers per year" in the United States.
The supposed worries about acrylamide fit nicely, of course, with CSPI's campaign against "junk food." As Jacobson wrote in 2002, "...many health experts have been urging people to cut back on lousy foods like fries all along. But the unwelcome contaminant [acrylamide[ provides yet another reason." CSPI, for instance, has yet to attack acrylamide in prunes, spinach alfalfa sprouts or beets.
But just what was CSPI's evidence that acrylamide "significantly increase[d] the risk of cancer in humans" resulting in "thousands of deaths" annually? The "evidence" provided by CSPI for their alarmist posturing over acrylamide was based entirely on the claims of certain CSPI experts in risk assessment and on the results, derived entirely from laboratory tests, of the effects of acrylamide in animals (rats and fruit flies).
CSPI's experts are an interesting group. Included is Dr. Samuel Epstein, Emeritus Professor of Environmental and Occupational Medicine at the University of Illinois. According to the Center for Consumer Freedom, which filed a response to CSPI's FDA brief on acrylamide, Epstein is "ranked as America's least credible scientist on issues of environmental cancer by the respected American Association for Cancer Research.... Epstein has claimed unproven cancer risks from food irradiation, hot dogs, Ritalin, flea collars, non-organic foods and non-organic shampoo. He has claimed that the cancer risks from using cosmetics and deodorant are equal to those associated with tobacco."
However, despite the acrylamide claims of experts like Dr. Epstein, even the laboratory data do not support CSPI's position.
For example, Don Mottram of the University of Reading in the UK told Nature (2002) that human's long history of cooked foods might well make them more tolerant of acrylamide than lab animals. More importantly, as Nature noted, the acrylamide induced cancers in lab animals were found only in animals that do not eat heated foods, and at doses more than 1000 times higher than those found in an average human diet. Indeed, the Swedish rats were fed acrylamide at doses from 1000-100,000 times those found in any human diet. While it is true that virtually any substance can harm, as the 16th century Swiss chemist Paracelsus noted "The dose makes the poison." And the acrylamide dose in food comes no where close to being a poison.
Joseph Levitt, Director of the FDA Center for Food Safety and Applied Nutrition, for instance, notes that significant cancer risk in the rats fed acrylamide was found only in a lifetime dose of 500 micrograms per kilogram of body weight (Levitt, "Assessing Acrylamide in the US Food Supply"). If one uses the data from Sweden's National Food Administration, a 154 pound person would have to consume a lifetime daily dose of 35,000 milligrams of acrylamide to have a risk for cancer equivalent to the lab rats. This translates into 180 pounds of fries or over 300 pounds of breakfast cereal PER DAY for life.
So based on the evidence from those Swedish rats, which is the only scientific evidence about cancer and acrylamide -- notice not cancer, acrylamide and humans -- that CSPI has ever presented, it is quite obviously the big eaters out there -- people consuming not just bowls but boxes of cereal each day -- who maybe, assuming that acrylamide works in humans the way it does in rats, need to be worried about acrylamide. Of course, even this very slender worry does not stand up when one turns to the science that has looked at the non-effects of acrylamide in real human populations. But then CSPI doesn't talk about that.
NEXT: What epidemiology tells us about acrylamide and cancer in humans.
John Luik is writing a book about health policy.