Contamination of Nigeria drinking water: A systematic review of public health implications

Abstract Sachet water has become the primary source of potable water for many Nigerian households because of its affordability and widespread availability. However, inadequate compliance with production standards has compromised progress toward the Sustainable Development Goals by increasing the risk of microbial and chemical contamination. This review evaluates sachet water production practices, contamination sources, associated public health risks, and the effectiveness of regulatory agencies responsible for quality control. The study followed the PRISMA guidelines and employed a Boolean search strategy to synthesize evidence from published literature. A comparative assessment of drinking water sources, including well water, stored water, rainwater, surface water, bottled water, and sachet water, was conducted. The findings revealed the presence of heavy metals such as mercury, arsenic, nickel, lead, cadmium, chromium, iron, and manganese in several drinking water sources. Although bottled water was generally safer, prolonged exposure to sunlight promoted chemical leaching. Microbial contaminants, including total coliforms, fecal coliforms, and Escherichia coli , were detected in most water sources except bottled water. Exposure to heavy metals and microplastics may increase the risk of chronic diseases, while residues of antibiotics such as ampicillin, ciprofloxacin, and tetracycline may contribute to antimicrobial resistance. Integrating Internet of Things (IoT) technologies and artificial intelligence into water quality monitoring, alongside improved infrastructure and stronger regulatory enforcement, could enhance sachet water safety and reduce dependence on packaged water, particularly in underserved communities.