Detection of persistent organochlorine pesticides in human milk by solid-phase extraction and gas chromatography

Objective To establish a detection method of organochlorine pesticides in human milk and to analyse their concentration in mature human milk from Beijing,Lanzhou and Hangzhou.Methods Human milk samples were extracted with acetonitrile.After purification and enrichment with acidificated silicone solid phase extraction column,the samples were analyzed by using gas chromatography.Results Linear ranges of eight pesticides were between 5 and 200 ng/mL,the correlation coefficients were 0.9955~0.9994,the limits of quantification were below 2.6 μg/kg.The average recoveries were 70%~122%,relative standard deviations were 3.91%~10.77%.Conclusion The matrix can be completely removed from human milk by combining usage of acidification and solid phase extraction.A method validation showed that this simple,accurate and rapid method was suitable for the analysis of the organochlorine pesticides in human milk.Since the usage of organochlorine pesticides are forbidden,the accumulation level of organochlorine pesticides in the human milk are decreased obviously.