May 7, 2008

Pacifica joins effort to stop aerial spraying

2 previous formulations provoked hundreds of health complaints

By Julia Scott / Bay Area News Group

Pacifica became the latest city to take a stand against the aerial spraying of pheromones to control the light brown apple moth last week amid continuing scientific debate over the safety and effectiveness of the plan.

Last week, prompted by worried residents, the Pacifica City Council unanimously passed a resolution opposing the use of pheromones to disrupt the mating patterns of the moth, unless the California Department of Food and Agriculture (CDFA) can show the public the spraying is safe for humans, animals and the environment.

"I think we share the concern that the state may need to do some additional work before they try to use this method of application. We're not against something being done, but we're against them not educating the public about the safety of the application method they're talking about," said Pacifica Mayor Jim Vreeland.

Pacifica is one of several north county cities whose neighborhoods will receive repeated spraying sessions starting as early as Aug. 17. The others include Colma, Brisbane, Daly City, South San Francisco and San Bruno.

At issue is not just the state's effectiveness in explaining the urban spraying program, which would cover nine Bay Area counties affected by the moth so far. It's the fact that in their haste to eradicate the moth, which preys on more than 200 species of trees, fruits and valuable crops, state officials declared a state of emergency that would permit them to start spraying before a full environmental impact review is released.

In March, Brisbane sent a letter to the CDFA requesting that before spraying, the agency specifically study potential effects of the pheromone compound on the San Bruno Elfin, Calippe Silverspot, and several other sensitive butterflies known to reside on San Bruno Mountain. The city also asked the CDFA to hold off on spraying until the environmental review is complete.

On Tuesday, several county residents asked the Board of Supervisors to pass a resolution similar to that in Pacifica opposing the aerial spraying. Supervisor Jerry Hill said the county already appointed a light brown apple moth subcommittee back in February to work with the county Health Department and determine whether existing science points to any health effects.

"For my part, I think further study is warranted," said Hill.

Scientists affiliated with the U.S. Department of Agriculture (USDA) are testing four new formulations of a pheromone pellet that will last 60 to 90 days on the ground, minimizing the need to spray more often, according to Larry Lyle, a spokesman for the CDFA. Two previous formulations used in aerial spraying over Santa Cruz and Monterey counties last fall provoked hundreds of health complaints. A government-appointed panel of scientists found no link, largely because medical tests are not available to diagnose related symptoms, and few reports of illness identified the location a person had been exposed. The state Department of Pesticide Regulation has previously stated that the product was so diluted it was unlikely to cause any heath effects.

Nevertheless, the USDA will now comply with a directive, issued by Gov. Arnold Schwarzenegger in late April, that requires additional safety tests to determine toxicity if the pheromone product is inhaled, eaten, absorbed in the eyes or by the skin. It will also look at what effects, if any, occur in exposed fish and other marine species. Those tests will be ready for review before the spraying starts, said Lyle.

"This goes beyond what the Environmental Protection Agency requires for a pheromone product, which history has shown has no history of causing health problems," said Lyle.

State officials say aerial spraying is the only method that can control the moth in the large area now under quarantine - 1,347 square miles in total. The USDA recently analyzed and rejected a proposal by a local environmental group to distribute more light brown apple moth traps in trees as an alternative to spraying. The analysis, released May 2, found the proposal unrealistic because it would require the installation of approximately 3,500 traps per square mile and scientists don't know whether it would be effective.

State officials also reject a theory that a natural approach would be more effective on a problem so widespread. A recent report, co-authored by Daniel Harder, executive director of the University of the California, Santa Cruz arboretum and Watsonville nursery owner Jeff Rosendale, suggests that the New Zealand light brown apple moth has been brought under control by natural predators like birds and other insects. Farmers used a pesticide to control the moth prior to 2001, but it also killed many of their former predators, according to the report. Since then, the problem has taken care of itself.

Primary CDFA entomologist Dr. Kevin Hoffman said that solution was untested and uncertain.

"If some native predators and parasites are inclined to attack the light brown apple moth, and I'm not saying some aren't, we don't know what level of control they'll provide in the long term," he said.

Meanwhile, some have questioned whether the light brown apple moth, which was first detected in Alameda County in March 2007, constitutes an emergency at all. No plants or crops have sustained any damage, although the moth has damaged grapes in New Zealand.

On April 24, a Santa Cruz County Superior Court judge ruled that the apple moth was not enough of a threat to justify allowing an emergency spray regimen to proceed before an environmental impact report is prepared for that county. The CDFA intends to appeal the decision.

Dr. James Carey, a professor of entomology at the University of California, Davis, doesn't believe the light brown apple moth infestation is even a recent one. Using a model based on the reproduction and migration patterns of the Gypsy moth, which came to the U.S. in 1869, Carey believes the apple moth has existed, undetected, in California between 30 and 50 years. He believes the only reason officials started noticing them after the first one was found in a backyard in 2007 was because they started setting traps for them.

Carey, an expert in Mediterranean fruit flies and a former advisor to the CDFA, rejects the theory that the moth has been transported exclusively on infected nursery plants, pointing to the fact that places adjacent to outbreak zones, like Fresno County, haven't seen their own outbreaks.

Lyle responded that neither his agency nor any professional entomologist had seen the apple moth until 2007.

"We have asked Dr. Carey for proof of his theories, but he hasn't been able to provide it. The science that we have in this program contradicts that," Lyle said.