Breast adipose tissue level of organochlorine pesticides as a risk factor in breast cancer: A cross sectional study in North Indian females

Abstract

Organochlorine pesticides (OCPs) were extensively used in India in agriculture as insecticides and in public health programs to control vector borne diseases like Malaria, and typhus. This rampant use led OCPs to persist in the environment due to their resistance to natural degradation and biotransformation, consequently, enter the human body through the food chain and bio-accumulate in adipose tissue as they are lipophillic. Exposure to OCPs have been linked to various diseases due to their endocrine disrupting properties, and lipophillic nature. The purpose of the study is to estimate the OCPs level in the breast cancer patients, and to compare the OCP levels within breast cancer patients based on their clinical features. A case control study was conducted on 100 breast cancer cases and 100 controls of benign breast disease patients. Quantification of OCPs was done by Gas Chromatography system equipped with 63 Ni Electron Capture Detector. Significantly higher levels of γHCH, Endosulfan-II, p'p’DDT and o'p’DDT were found in cases with respect to controls (p < 0.05). The odds ratios (ORs) show a significant association of Endosulfan-II (1.3) and p'p’DDT (2.7) levels with risk of breast cancer. Further, significantly higher levels of γHCH, p'p’DDT and Endosulfan-II were found in lymph node metastasis cases and γHCH and pp’DDD in advanced tumor stage cases as compared to the cases without lymph node involvement, and early tumor stage respectively. The findings of the present study support the contribution of OCPs in the pathophysiology of breast cancer. Further, OCPs like p’p’DDT, Endosulfan-II, and γHCH may promote the progression of breast cancer by influencing the metastatic ability through lymphatic pathway.