Nitrogenous Compound Exposure in Unsanitary Rural Environments: A Case Study from Al Hoceima Province, Northern Morocco

¹ Laboratory of Applied Sciences (LSA), Environmental Management and Civil Engineering research team (GEGC), ENSAH, Abdelmalek Essaâdi University, Tetouan, Morocco.
² Laboratory of Research and Development in Engineering Sciences, Faculty of Sciences and Techniques of Al-Hoceima (FSTH), Abdelmalek Essaâdi University, Tetouan, Morocco.
³ Laboratory of Engineering Sciences and Applications (LSIA), Research Team: Materials Science, Energy, and Environment (SM2E), ENSAH, Abdelmalek Essaâdi University, Al Hoceima, Morocco.

^* Corresponding author: a.bourjila@uae.ac.ma

Abstract

Groundwater is a crucial drinking water resource for rural communities; however, the absence of adequate monitoring programs in these regions often results in uncertainties about groundwater quality. This study focuses on assessing the impact of nitrogen compounds from domestic wastewater on groundwater in rural communities within the province of Al Hoceima. The hydrochemistry of 33 groundwater samples was analyzed using various methods, including descriptive statistics, the Nitrate Pollution Index (NPI), the Chronic Health Risk Index (CHR), and a GIS-based spatial analysis. The investigation revealed significant contamination by nitrogen compounds in regions characterized by high population density. In these areas, nitrate (NO₃^-) and nitrite (NO₂^-) concentrations exceeded 50 mg/l and 0.2 mg/l, respectively, surpassing the WHO recommended limits. Notably, NO₃^- levels ranged from 0 to 89.63 mg/l, with 84.84% of groundwater samples contained more than 10 mg/l. The NPI values ranged from -1 to 3.48, with 33.33% of the samples were categorized as significantly and very significantly polluted. Additionally, CHR values ranged from 0 to 2.43 for adults, 0 to 2.03 for children, and 0 to 2.51 for infants. The CHR values exceeded 1 suggests that the contamination observed in the samples can be attributed to the widespread use of septic tanks in densely populated regions. Thus, to ensure the safety of rural communities, further assessments of health risks are mandatory.