Human Health Risk Assessment of Organochlorine Pesticide Residues in Selected Portable Drinking Water Produce and Sold in Ilaro, Ogun State

Ukonu, Christian U. & Olowofila Inioluwa O, Volume 3 Issue 2, December 2022 Pages 138-149, Published: 2022-12-16

Abstract

The importance of safe drinking water cannot be over-emphasized. The lack of safe drinking water by the government led to a paradigm shift to dependent on potable water as a safe haven for good drinking water. This study aimed at assessing the health risk of organochlorine pesticide (OCP) in potable water produced and sold in Ilaro. Ten water samples from five major water factories were collected. The liquid-liquid extraction of the samples was carried out using dichloromethane (DCM). The OCP was analyzed quantitatively using electron-captured detector Gas chromatography and the human health risk was obtained using the Hazard index(HI) model. The result obtained revealed the presence of endosulfan ether, dieldrin and mitotane in TT water samples with mean concentration values of 6.34 µg/l, 0.218 µg/l and 12.12 µg/l respectively, which are all higher than the WHO maximum residue limit (MRL) of 0.1 μg/l for drinking water. Endosulfan ether and dieldrin showed a hazard index HI>1 which is an indication of Oncogenic health risk to both adults and children, except mitotane with HI<1. FC water samples revealed five residues with mean values higher than the recommended WHO limits for drinking water, except mitotane. Only endosulfan ether and dieldrin have HI>1 in both adults and children implying Oncogenic health risk, while endosulfan had HI>1 in only children and less than 1 in adults. Federal Polytechnic Ilaro (FPI) water samples had only two residues namely endosulfan ether and dieldrin with 1.31 µg/l and 0.073 µg/l respectively, higher than the recommended limit; both also have HI>1 for both adults and children. This shows Oncogenic health risks. Alpha-Lindane, dieldrin, endosulfan ether and mitotane were present in EL water samples with mean values 0.15 µg/l, 0.724, 0.78 and 0.01 µg/l higher than the WHO limit, except mitotane which is lower. All except mitotane had HI>1, posing an Oncogenic health risk to the consumers. In VP water samples, five residues endosulfan ether 28.43 µg/l, dieldrin 0.615 µg/l, mitotane 0.03 µg/l, Isodrin 0.576 µg/l and Endrin 0.011µg/l; higher than the WHO limit. The HI>1 for endosulfan, dieldrin and endrin in both adults and children, while mitotane is H<1. The result of this study implies that virtually all the water samples from the five major factories in Ilaro are contaminated with a high concentration of OCP higher than the WHO recommended boundary for drinking water and are of anthropological Oncogenic health risk to the consumers of the potable water both the children and adult, especially after long term ingestion as indicated using Hazard Index Model