Determination of 23 Organochlorine and Organophosphorus Pollutants in Water by Solid Phase Extraction and GC-MS

Objectives To establish a quantitative method to detect the pollution of organochlorine and organophosphorus pesticide in drinking water in some regions of Jiangsu province with a method of combining solid phase extraction and gas chromatography-mass spectrometry.

Methods Source water and finished water samples were collected from 13 water plants in Jiangsu province. Organochlorine and organophosphorus pesticides in drinking water samples were extracted by PLS solid-phase extraction column and then eluted by ethylacetate-methylene chloride (1:1), and were detected by gas chromatography-mass spectrometry.The specific retention times, qualifier and target ions, and the qualifier/target abundance ratio were used to identify individual pesticides. Quantifications were based on internal standard addition.

Results The linear ranges of standard curves for target compounds were 0.2~1.0 ng/L and the R² values were greater than 0.997.The detection limits, recovery rates and relative standard deviations (RSD) were 0.3~6.4 ng/L, 70.0%~118.0% and 4.5%~12.3%, respectively. In 49 source water and finished water samples, the detection rate of organophosphorus pesticide dichlorvos was 100% and the detection rates of organochlorine pesticide β-BHC and lindane were 58%~100% and 28.0%~41.7%, respectively.

Conclusions The pollution of 23 kinds of organochlorine and organophosphorus pesticides could be detected by this method. Dichlorvos, β-BHC and lindane were detected in higher rates. Monitoring and evaluating the environmental risks of pesticide pollution should be strengthened, and relevant departments should be urged to develop standard limits for the residue of pesticides.