Californians are upset over a government report denying aerial spraying had caused respiratory problems in Santa Cruz and Monterey counties in autumn. The spraying had been undertaken against the light brown apple moth.
A 32-page report released Thursday by the Office of Environmental Health Hazard Assessment found that the 487 complaints gathered after the spray campaigns were not detailed or consistent. As a result, the analysis was inconclusive.
"We were not able to establish a link, one way or another," said Joan Denton, director of the state office, which analyzes toxic threats to the environment.
Critics of the spraying program quickly attacked the findings. The report is a "whitewash," said Frank Egger, president of the North Coast Rivers Alliance.
Most of the health complaints were submitted by residents of the two counties shortly after their communities were sprayed with Checkmate, a formulation of microscopic particles containing insect hormones, called pheromones, that disrupt the apple moth's mating behavior.
Only 44 of the complaints, however, were submitted by physicians following state protocols prescribed for the purpose. Three-quarters of the citizen reports failed to pinpoint the time or place of possible exposure to the spray, according to the state analysis, and "very few" provided addresses to help researchers match exposure to location.
The state study also noted that, although there were 75 reports of patients seeking medical care after the spraying, most of the reports - even those requiring medical attention - were consistent with rates of common respiratory problems, says Sabin Russel, writing in San Francisco Chronicle.
"My hope is that today's report will help ease the minds of those concerned about the light brown apple moth eradication program," said A.G. Kawamura, secretary of the California Department of Food & Agriculture, which views the Australian pest as a major threat to the state's fruit industry.
The report was a big disappointment, however, to Michael Lynberg, a Pacific Grove technical writer who gathered 300 complaints after his entire family was sickened shortly after Checkmate was sprayed in his neighborhood. "I was really hoping they would come to our rescue," he said. "I was hoping common sense would prevail."
As a result of the inconclusive findings, the state agency is recommending that a system be set up to allow for the consistent collection of health complaints before additional aerial spraying is conducted. That would include the eventual setup of a toll-free hot line for the public, and more vigorous efforts to collect health reports from doctors.
The latest report also reiterated earlier state findings suggesting that the concentration of the hormones - about a tablespoon per acre - was well below any limit known to cause health problems. Similar formulations have been used, even in populated areas, for 10 years without causing health problems, according to Department of Food & Agriculture spokesman Steve Lyle.
"Today's finding is significant," he said. "It found no link. We look at it as another step in a long history finding no indication of human health problems with aerial spraying of pheromone products."
Santa Cruz resident Roy Upton, a critic of the spraying program, said that the latest report was "predictable" because it was very difficult to prove the cause of any health problem based on anecdotal reports.
But then researchers had not asked the question whether the microscopic particles used to encapsulate the moth hormones might themselves cause respiratory problems.
"About 20 percent of these particles are under 10 microns. The American Lung Association considers that to be particulate pollution that can get into the bloodstream, cause respiratory problems, bronchitis, asthma and death," he said. "They are only addressing the issue of pheromone exposure."
Although Checkmate is known to cause mild skin and eye irritation, it is considered much safer than pesticides that might be employed to kill the moths outright. However, 70 percent of health complaints logged by the state involved respiratory symptoms; only 3 percent were exclusively skin or eye problems.
Among the 44 reports filed by physicians, 13 involved individuals who had a prior history of asthma. There were three reports from doctors about patients who had no history of asthma, but came to their offices wheezing.