Rat Cancer Is Not Human Cancer

To the Editor:

Scientists and the public have reason to be excited about the technique developed by Dr. Robert A. Weinberg to induce malignant transformation in human cells (front page, July 29). Scientists induced such cancerous changes in rodents 15 years ago.

The fact that it took so many years to accomplish this feat in humans illustrates how differently carcinogens affect rodents than humans.

Environmental activists would have us ban any substance that induces cancer in lab rodents, even though tremendous doses are required to cause this effect. This is mistaken. Rats and mice are not little people. Rodents are far more susceptible to cancer induction than humans. Merely because chemicals or certain foodstuffs produce tumors in rodents does not mean that humans will be harmed.