Trucks will be out spraying parts of Staten Island and Queens in an effort to reduce the risk of West Nile virus.
Spraying will begin at 8:15 p.m. Thursday, weather permitting.
The following areas will be affected in Queens: Corona, Flushing, Fresh Meadows, Forest Hills, Kew Gardens Hills, Rego Park, Pomonok, and Queensboro Hills.
The Staten Island neighborhoods of Livingston, Port Richmond, Mariners Harbor, Elm Park and West Brighten will be sprayed.
The Health Department said the pesticides pose no threat to humans.
People with asthma and other respiratory conditions are encouraged to take precautions to minimize direct exposure.