Source apportionment and health risk assessment of nitrate in foothill aquifers of Western Ghats, South India

Authors

Banajarani Panda, Annamalai University
S. Chidambaram, Kuwait Institute for Scientific Research
Daniel D. Snow, University of Nebraska-LincolnFollow
Arindam Malakar, University of Nebraska - LincolnFollow
Dhiraj Kr Singh, Grass Roots Research and Creation India (P) Ltd
L. Ramanathan, Jawaharlal Nehru University

Date of this Version

12-9-2021

Citation

Ecotoxicology and Environmental Safety 229 (2022) 113075. https://doi.org/10.1016/j.ecoenv.2021.113075

Comments

Open access.

Abstract

The present research reports the level of nitrate (NO₃^-), associated health risks and possible sources of contamination in groundwater from south India. Many samples (32%) are above or approaching the recommended level of NO₃^- for safe drinking water. The correlation analysis indicates different sources of NO₃^- contamination in different regions rather than a common origin. The isotopic measurements provide information about potential nitrogen sources contributing NO₃^- to the groundwater. Based on isotope analysis, the sources of NO₃^- in the groundwater of this region are likely to be from (a) septic sewage (b) organic nitrogen (animal and livestock excreta) (c) sewage (domestic & chemical fertilizers). Among the sample analyzed sewage, manure and septic sewage contribute 46%, 23% and 31% NO₃^- to groundwater. The HQ > 1 indicates non-carcinogenic health risk due to consumption of high NO₃^- in drinking water. Among the studied age groups, infants are exposed to higher risk than children and adults. Results indicate that groundwater of this region is polluted with NO₃^- due to anthropogenic activities. Continuous consumption of such water may pose serious health risk to the residents.