Organic farmers urge state to cancel aerial spraying over southeastern Massachusetts

By Kay Lazar, Globe Staff

Organic farmers are urging the state to cancel this weekend’s scheduled aerial spraying of 21 communities in southeastern Massachusetts, saying the pesticide being used to kill disease-carrying mosquitoes can cause health problems and harm fish, birds and other insects.

“We call on the state to implement more effective and healthful ways to prevent outbreaks of mosquito-borne diseases,” Jack Kittredge, policy director of the Massachusetts chapter of the Northeast Organic Farming Association, said in a statement.

Earlier this week, state health officials announced that aerial spraying would begin Friday evening, weather permitting, and continue Saturday night to prevent the spread of eastern equine encephalitis in southeastern Massachusetts.

On Friday, the state Department of Public Health released a schedule showing that spraying would begin at 8:15 p.m. and continue through 2:00 a.m. both evenings in the following towns: Acushnet, Berkley, Bridgewater, Carver, Dighton, East Bridgewater, Easton, Freetown, Halifax, Hanson, Kingston, Lakeville, Middleborough, Norton, Pembroke, Plympton, Raynham, Rehoboth, Rochester, Taunton, and West Bridgewater.

Weather conditions including temperature, wind speed and precipitation can impede aerial spraying activities, the department said. Residents may check the agency’s website at www.mass.gov/dph for updates throughout the spraying event. Residents can also get a daily 5 p.m. update on spraying activities by calling 2-1-1.

Mosquitoes infected with eastern equine have been found in Carver, Easton, and Lakeville -- weeks earlier than expected -- and officials worry they will find even more as the summer progresses.

They said the chemicals to be used are sumithrin, a pesticide that is combined with piperonyl butoxide, a compound that activates the sumithrin. The pesticide is also known by the brand name Anvil 10+10.

Kevin Cranston, director of the state’s Bureau of Infectious Disease, told the Globe that the product was chosen because of its effectiveness against mosquitoes, and because it breaks down rapidly when exposed to sunlight. He said that it has “a very low residual effect and a very low toxicity to humans and animals.”

The organic farm organization, however, said the product is toxic to fish and bees, and is not approved for use on food crops, fodder crops, pasture or grazing areas.

The organization said more effective means of controlling mosquito populations are available, such as reducing open containers of still water, including bird baths and wading pools, where mosquitoes lay eggs.

State officials said they have taken precautions to avoid sensitive farms and waterways. State health commissioner John Auerbach told the Globe that spraying will be done with a GPS system programmed to cut off spraying over a body of water used for drinking or a certified organic farm.

Officials also said that aerial spraying of pesticides reduces but does not eliminate the risk of mosquito-borne illness. They urged all residents, whether inside or outside the spray zone, to continue taking precautions to avoid mosquito bites. These include using insect repellent, covering exposed skin when outside, and avoiding outdoor activities between the hours of dusk and dawn, when mosquitoes are at their most active.