No Major Malathion-Spraying Side Effects Found : Health: Medical tests show few problems even among asthmatics and the allergic in areas where the Medfly was battled. Growers are relieved by the findings, environmentalists unconvinced.

The first medical tests ever done on Orange and Los Angeles county residents exposed to malathion spraying show that the controversial pesticide caused no major side effects, even in those people most likely to suffer allergies and asthma, according to newly released studies.

Los Angeles County health officials, who conducted the ground-breaking studies on more than 100 people, said the findings reassure them that the threat was extremely low in the neighborhoods sprayed with the toxic pesticide between fall of 1989 and summer of 1990.

In all, about 1.5 million Southern Californians, including 400,000 in northern and central areas of Orange County, lived in areas that were repeatedly sprayed by helicopters in the state’s effort to combat the Mediterranean fruit fly, a pest capable of major damage to the state’s agricultural industry.

The medical tests mirror past findings but are the first ever performed on malathion spray-zone residents, said Dr. Paul J. Papanek Jr., who coordinated the studies as head of toxics epidemiology at the Los Angeles County Department of Health Services.

“The health effects are not zero, and that’s because there appear to be some people who are allergic to malathion or the bait it is mixed with,” Papanek said. “But the allergic reactions appear to be infrequent and overall mild. By and large, they are not very often and none are very serious.”

Among the health department’s findings:

* None of 47 people tested for skin reactions developed dermatitis or suffered skin allergies when a mixture of malathion and bait was painted on their backs in patch tests.

During scratch tests, however, when the skin on the arms was pricked and a small amount of malathion was applied, two children suffered mild reactions. One child suffered a rash on his arm from the corn syrup used as bait in the malathion mixture, while the other child showed possible minor skin reddening from the pesticide. Papanek said that while these symptoms do show irritation, neither is a sign of allergies.

“We had no clear-cut contact dermatitis at all and two cases of hives that were very mild,” Papanek said.

All the tested people had complained of rashes after spraying in their neighborhoods. Many suffered allergies, so they were considered a group more likely than the general public to suffer skin reactions to the sprayings.

* Fifteen asthmatics who lived around downtown Los Angeles within a malathion spray area did not suffer any more respiratory problems than those in a control group outside spray zones. Papanek said some complained of scratchy throats and signs of possible irritation, but the studies found no worsening of their asthma or any increased blockage of airways.

“The Medfly eradication campaign is not likely to cause an exacerbation of asthma in most asthmatics,” the health department’s report said.

* Urine tests, which measured the amounts of pesticide people absorbed through their lungs, mouths or skin, showed that concentrations were much lower than scientists originally believed and were much less than the amount known to cause illness.

The urine specimens were collected from 67 people in sprayed neighborhoods, including 17 Orange County residents, 37 Los Angeles County residents, five children at a Los Angeles County day-care center and eight agricultural workers. All of the participants except the day-care center children and agricultural workers had called their local health department to complain about symptoms from the aerial spraying.

Some of the urine samples showed minute amounts of malathion, but Papanek’s report said these results were barely detectable and hundreds of times lower than the levels considered toxic enough to cause illness.

“It takes a large amount to be poisoned, and we’re not even close to poisoning,” he said. “Even the highest levels are on the low side compared to a toxic dose.”

State agricultural officials repeatedly said during the nine months of spraying that the risk to the public was minimal, but local health departments received several thousand complaints of illness from residents who related them to the pesticide.

In late March, state health officials announced that their survey of existing scientific studies concluded that there were no significant health dangers, but they nonetheless recommended that spraying be reconsidered and used only as a last resort.

They were concerned about unresolved medical issues, especially the effect of the sprayings on sensitive groups of people with allergies and asthma.

The state report, however, did not include tests on actual spray-area subjects. The Los Angeles County report, using resident-test sites in Irvine and elsewhere in the Southland, was not completed until April, and its findings were not included in the earlier state report.

Groups representing California growers, who consider the Medfly a major threat to their multibillion-dollar industry, are relieved by the Los Angeles County findings, while environmentalists and anti-spraying activists said they remain skeptical.

“People get so concerned over malathion spraying, but now they can see that this testing is going on and the results are reassuring,” said Debra Calvo of the Alliance for Food and Fiber, a Los Angeles-based trade group for growers.

But Mollie Haines, a Garden Grove housewife who was a vocal malathion opponent in the Medfly battle because her neighborhood was sprayed nine times, said Tuesday that the test results did little to reassure her.

“I’m not just concerned about rashes, but long-term health effects, and no one is studying that,” she said.

But Papanek said the tests show that without direct skin contact to the pesticide, there were no health effects at all because the doses sprayed were so low in strength.

“If you are indoors or don’t come in contact with the garden the next day, we don’t find anything,” he said. “It shows people don’t have to move out (of spray areas) to avoid even these types of milder problems.”

He added, however, that more comprehensive studies should be done on asthmatics since the tested group was small. But his proposal to obtain more state funding was rejected.