Determination of pesticides in lettuce using solid-liquid extraction with low temperature partitioning.

This work describes the optimization and validation of a method employing solid-liquid extraction with low temperature partitioning (SLE/LTP) together with analysis by gas chromatography with electron capture detection (GC/ECD) for the determination of nine pesticides (chlorothalonil, methyl parathion, procymidone, endosulfan, iprodione, λ-cyhalothrin, permethrin, cypermethrin, and deltamethrin) in lettuce. The method was found to be selective, accurate, and precise, with means recovery values in the range of 72.3-103.