Man Behind Malathion Safety Study Disavows It

In a potentially embarrassing blow to the state’s aerial spraying campaign to eradicate the Medfly, an author of a 1980 state study used to demonstrate the safety of malathion has disavowed the report’s findings, saying the pesticide may pose a danger to infants, the elderly and the sick.

Marc A. Lappe, a professor of health policy and ethics at the University of Illinois, who was part of a state risk assessment team, said he found in 1980 that malathion could cause six extra cases of cancer for every million people--six times greater than what the report officially concluded.

State health officials, however, immediately discounted Lappe’s criticism, calling the changes made in the report scientifically insignificant. Moreover, they said, later studies by federal health authorities found the chemical did not cause cancer.

Despite the later studies, Lappe said in an interview Monday, he is concerned about the possible health hazards of spraying. While six cancer cases in a million people are relatively few, he said, they suggest a potential hazard.

“The public has been ramrodded into accepting this without their basic right to have a full airing,” said Lappe, who resigned his state post in 1981 because of the changes made to the report. “It could be quite dangerous to infants, the elderly and the infirm.”

Federal policy generally assumes that a one-in-a-million risk is insignificant. But state regulation puts the standard at less than 1 in 100,000 for the enforcement of Proposition 65, the 1986 ballot initiative that requires businesses to warn people who are exposed to certain toxic chemicals.

Dr. James Stratton, a medical epidemiologist with the state Department of Health Services, said that five years after the state’s report was released, the National Toxicology Program determined that the cancer risk from malathion was virtually undetectable.

Dr. Ephraim Kahn, Lappe’s supervisor in 1980, said the study purposely assumed an exaggerated cancer danger. Such “worst case” assumptions make the difference in Lappe’s numbers insignificant, Kahn said.

“The implication that his numbers were changed to hide some serious effect is just ridiculous,” said Kahn, who is known within the department as a supporter of strong pesticide regulations.

The controversy over the report erupted this week because of an affidavit Lappe filed in support of a suit by the cities of Garden Grove, Huntington Beach and Westminster to stop the spraying.

At the heart of the controversy is National Cancer Institute study that looked at the possible cancer risk of malathion in rats and mice. Researchers found a slightly higher incidence of liver cancer in the animals, but nothing that was statistically significant. Nevertheless, to be on the conservative side, Health Services decided to use the institute’s worst-case figures in its 1980 report.

Lappe--who is recalled by former colleagues as brilliant, but stubborn and single-minded in his views--said he took the strictest approach he could imagine. He assumed the greatest cancer risk possible from the institute’s study, even though it was statistically insignificant; he chose as his hypothetical subject a naked baby lying outside and assumed that the baby had come in contact with all the malathion sprayed over 30 square feet.

Lappe’s calculation showed that there could be as many as six extra cancer cases in a million people, assuming six sprayings. He said the figure could go up to 10 in a million with 12 sprayings--what the state proposes for some Southland areas.

Kahn said he later adjusted the figures downward by assuming slightly less exposure to the hypothetical baby because he believed the change was scientifically insignificant and the result would be better understood by the public.

Dr. Lynn Goldman, chief of environmental epidemiology and toxicology section at Health Services, said she also believes such a change is virtually meaningless in a risk assessment.

“There is a lot of uncertainity in risk assessment,” said Goldman.

Regardless of Lappe’s calculations, Stratton said the 1980 study became irrelevant five years later when the National Toxicology Program, in conjunction with the National Cancer Institute, released a new study that found malathion noncarcinogenic.

“Malathion is frankly not among the list of chemicals that your readership should be worried about” as a cancer risk, he said.

State officials Monday revealed plans to set up a Southern California malathion health advisory panel and conduct air and water quality reviews in local spray areas.

The panel--to be formed as early as this week--would be made up of area health professionals. It would advise the state on the possible health implications of the spraying, as well as educate the public on its findings, Stratton said. Officials of the Department of Food and Agriculture said they were confident that the local panel’s conclusions would mirror the state’s findings.

In another development, Dr. Paul Papanek, chief of the Toxics Epidemiology Program of the Los Angeles County Health Department, proposed that the state Department of Food and Agriculture pay for free testing for people who believe they have had an allergic response to malathion. He estimated the tests would cost $200 to $300 per person and involve about half a dozen people a week.

He said the proposal was spurred by telephone calls from concerned spray zone residents and by the stepped-up spraying schedule.

An independent lab in Palm Desert, meanwhile, is offering to provide malathion testing of produce, ground water and soil samples, at cost, to residents, said Craig Eaton, the lab’s marketing director. For $25, the lab will analyze mail-in samples.

Eaton said he is working with representatives of the Mt. Washington Assn., which has been active in the movement to stop malathion spraying.

The lab, which opened in December, is registered by the state Department of Food and Agriculture but not yet accredited, said a department spokesman. Registration is mandatory but accreditation is not. Freelance writer Kathleen Doheny contributed to this story.

MEDFLY SPRAYING MAP: B2.