HPLC Uv‐Vis Analysis of Multiple Pesticides Extracted from Biological Tissues: Effects of Acetonitrile/Hexane on Detection.

Abstract

Exposure to chlorinated pesticides continues to be of great public health concern. They are extremely persistent; accumulate in sediments, plants, and animals with high bioaccumulation potentials in human contributing to chronic health conditions. Effective and comprehensive methods to determine presence of multiple pesticides (MP) in biological samples are desirable. We have determined the concentration of MP in different organs from rats exposed to MP (endosulfan 1/2, Endrin, Dieldrin, 4,4-DDT, and Aldrin: 1/100 (LD50) in a mixture orally) for 2 weeks in corn oil. Rats' livers, hearts, kidneys, and brains were soaked and homogenized in acetonitrile or hexane to determine better extraction. Samples were homogenized, centrifuged, dried, and reconstituted in 1 mL hexane or acetonitrile. Standards of individuals and mixtures were run to obtain standard calibrations and retention times using HPLC Uv-Vis. The standards eluted at 12.90, 14.90, 15.77, 15.90, 20.06, and 29.20 minutes for (endosulfan 1 and 2, Endrin, Dieldrin, 4, 4-DDT, and Aldrin, respectively. Acetonitrile extracted samples showed significantly higher yield of chlorinated pesticides compared to hexane with a ratio (Acetonitrile: Hexane) of 13:1 (brain); 18:1 (kidney); 366:1 (heart) and 1,186:1 (liver) for the detection of endosulfan 1. While endosulfan 2 showed 1:1 (brain); 39:1 (kidney); 161:1 (liver). Except dieldrin, all other pesticides were detected with lower ratios. Thus, our results indicate that the media used to extract chlorinated pesticides samples could have significant effects on the yields and hence quantification probably leading to under estimation of chlorinated pesticides burden in biological systems/samples.