The Columbia Center for Children\u2019s Environmental Health (CCCEH) previously reported widespread residential insecticide use in urban communities in New York City. Research suggests that pyrethroids are replacing organophosphates (OPs) in response to 2000\u20132001 US EPA pesticide regulations restricting OP use. A systematic assessment of active ingredients used for residential pest control is lacking. We queried a database of pesticide applications reported by licensed applicators between 1999 and 2005 and surveyed pest control products available in 145 stores within 29 zip codes in the CCCEH catchment area including Northern Manhattan and the South Bronx. Pyrethroids, pyrethrins, piperonyl butoxide, and hydramethylnon were the most common insecticide active ingredients reported as used by licensed pesticide applicators within the 29 zip codes of the CCCEH catchment area between 1999 and 2005. Use of certain pyrethroids and some non-spray insecticides such as fipronil and boric acid increased significantly by year (logistic regression, OR41.0, Po0.05), whereas use of OPs, including chlorpyrifos and diazinon decreased significantly by year (logistic regression, ORo1.0, Po0.05). Among pesticide applicators, the most commonly applied active ingredients were formulated as spray applications. With 145 stores in the catchment area, 120 (82.5%) carried at least one insecticide. Spray cans were most common (114\/120 stores, 95%); gels were least common (31\/120 stores, 25.8%). Among spray formulations, pyrethroid insecticides were the most common pesticide class and permethrin, a pyrethroid, was the most common individual active ingredient. In 2007, one store carried a product containing chlorpyrifos and one store carried a product containing diazinon. This survey suggests that certain pyrethroids and non-spray insecticides.<\/p>\n