Method development for pesticides analysis in breast milk using stir bar sorptive extraction followed by TD/GC/MS.

摘要

Persistent organochlorinated (OC) pesticides are found to be bioaccumulated and biomagnified in the food chain. They pose a risk of causing adverse effects on biological species including humans. Ongoing studies of OC pesticides are focused on their fate and transport in the environment, and their impact on the ecosystem and human health. Most analytical methods for studying OCs require intensive manpower and the use of organic solvents in large quantities. The purpose of this study was to develop a more environmental friendly method to analyze OC pesticides in human breast milk. A newly developed technique called stir bar sorptive extraction (SBSE) was carried out in this study. The SBSE technique in this study uses only isopropanol and water as solvents. It is a simple, cost-effective, and rapid technique when compared to the traditional liquid extraction methods. Target compounds in this study were DDT (Dichlorodiphenyl trichloroethane), DDE (dichlorodiphenylchloroethane) and DDD (dichlorodiphenyl-dichloroethane). The analytical method developed in this research to analyze target compounds used (1) use 0.01% (w/v) of sodium hydroxide with sonication for 30 minutes to break up lipid and release organic compounds into aqueous solution; (2) 25% isopropanol/water was then added as the solvent for SBSE and was stirred for 2 hours. Using this new methodology the target compounds could be detected at a concentration of 100 ppb or higher in fresh human breast milk.