Health risk assessment of nitrates in the groundwater of Beni Amir irrigated perimeter, Tadla plain, Morocco

Abstract

Shallow groundwater contaminated with nitrates may result in human health risks. Groundwater quality in the Beni Amir irrigation perimeter in Tadla plain, Morocco, is influenced by agriculture and farming-related activities. This study was carried out to assess the nitrate contamination of groundwater for drinking purposes by comparing it to Moroccan and WHO guidelines, and by estimating the potential human health effect of nitrates using the model recommended by the USEPA. The results showed that the nitrate content of groundwater fall between 0 and 82.08 mg L−1 (mean 24.73 mg L−1), with 38.10% of groundwater samples exceed the Moroccan and WHO limits for drinking. Groundwater nitrates mainly originated from intensive agricultural practices. The health effects of oral exposure to nitrate are higher than those of dermal exposure. For non-carcinogenic risks, 57.14% of samples showed hazard index (HI) values >1, indicating potential risks. The non-carcinogenic risk for infant and female are higher than that for females and males. The results of this study will offer a health risk reference for local residents and can help to propose suitable management ensuring safe drinking water.