State Panel Recommends Malathion for El Cajon

The Science Advisory Panel of the state Department of Food and Agriculture has recommended that San Diego County begin its first aerial spraying of malathion May 21 over 16 square miles in El Cajon, county officials confirmed Thursday.

According to Gary A. Reece, chief of agriculture services of the county Department of Agriculture, Weights and Measures, the five-member panel has advised top state officials that three aerial applications of the potent pesticide are essential to prevent a widespread infestation of Mexican fruit flies, or Mexflies.

In addition, the panel advised that 320 million sterile Mexflies should be released here during the four months that follow the malathion spraying. The sterile male flies mate with fertile females, helping to breed the pest out of existence.

Henry Voss, director of the state Department of Food and Agricul ture, is expected to make a decision based on the panel’s recommendations today, Reece said. If he concurs with the panel, Voss will ask Gov. George Deukmejian to declare a state of emergency, educational public hearings will be scheduled in the El Cajon area and helicopters will be outfitted to begin the nighttime spraying, Reece said.

“It’s a very difficult decision to make, because obviously an aerial spraying of malathion is a controversial decision,” Reece said, adding that Voss and his staff “are well aware of the implications of this kind of decision. But they are also aware of the problems that will result if they don’t take action.”

Voss took similar action in Los Angeles County on Thursday, announcing that aerial malathion spraying will soon begin in a 20-square-mile area in Compton believed to be infested with Mexflies. About half that area is already being sprayed with malathion to eradicate the Mediterranean fruit fly, or Medfly, and will require no extra treatment.

El Cajon’s Mexfly problem prompted the advisory panel to convene Wednesday. Since April 25, three Mexflies--one mature male and two egg-bearing females--have been trapped within a quarter of a mile of each other in a residential area near John F. Kennedy Park just south of Interstate 8.

Scientists agreed that, although isolated trappings of Mexflies are not uncommon in the county, the discovery of three in such a small area is cause for concern. After the Medfly, Mexflies are considered the most dangerous pest to agriculture.

At a press conference late Thursday, county officials seemed braced for an outcry. Should the spraying be approved, they said, less than 3 ounces of malathion, suspended in corn syrup bait, will be sprayed over each acre of land--far less than many homeowners use in their gardens.

“Malathion in these particular concentrations (is) one of the best-studied pesticides around,” said Dr. Donald G. Ramras, county health officer. “There is no health risk at all, no cancer risk, none of these other things, with the possible exception that, just like any other material, some people may be allergic to it. . . . I can certainly understand why they don’t want it raining on them, but there’s no health risk.”

David Kellum, a county entomologist, said malathion has a two- to seven-day half-life, meaning half of it breaks down within a week. He also said it does not leach into the soil, so it does not pose a danger to the water table.

Reece said that, unstopped, Mexflies are capable of devastating agriculture here and in other parts of the state. “It’s not just this county. Once it was established here . . . it would affect citrus, avocados, all those kind of crops in this county and throughout the state.”

Stronger fliers than Medflies, Mexflies could spread rapidly, Kellum said. “One female can lay up to 1,000 eggs. If we find two or three, you have to make the assumption that there are more out there.”

Reece said that, if spraying begins, the state will distribute pamphlets to let residents know whom they can call regarding health and environmental concerns.

Dianne Jacob, administrative assistant to county Supervisor George Bailey, spoke on behalf of Bailey, who is in Washington:

“Mr. Bailey’s main concern would be the public health and safety of the people in the area and the protection of the agricultural industry, not only in San Diego, but . . . the (agricultural) industry in the state, too.”

The new round of aerial spraying comes as agriculture officials are struggling to wind down a massive nine-month pesticide campaign they have waged against the Medfly in Los Angeles, Orange, San Bernardino and Riverside counties. They hope by the end of May to phase out all but 48 square miles of infested territory--if no new Medflies are found.

Times staff writer Ashley Dunn contributed to this article.

FAMILIAR PEST--The Mexican fruit fly is faster and bigger than the Mediterranean variety. B1