State and federal officials repeatedly sprayed residential areas in Monterey and Santa Cruz counties last fall to combat the light brown apple moth, which has infested 12 counties stretching from north of San Francisco to Los Angeles.
Dozens of people complained of feeling short of breath and experiencing sharp stomach pains after the first application of a pheromone spray called CheckMate.
Those numbers quickly grew as the aerial spraying continued.
The state Department of Food and Agriculture has received a total of 330 illness reports since the pest eradication program began in September, spokesman Steve Lyle said Friday.
Some of those reports may be duplicative, and many don't include comprehensive data about people's symptoms or personal information, he said.
"The agencies with the jurisdiction to review the product have told us it's safe to use," Lyle said. "(They) came to the conclusion that the Checkmate products were unlikely the cause of the illnesses reported."
A coalition of citizen groups reported getting 290 additional illness complaints and called Friday for Gov. Arnold Schwarzenegger and the state legislature to get involved.
"The number of people who have reported adverse reactions is alarming, and I believe further spraying must be halted until we can be certain it is safe," said Santa Cruz City Council member Emily Reilly.
An advisory group working with state officials and the U.S. Department of Agriculture is expected to announce plans for the pest eradication campaign later this month.