Physicochemical and Microbial Quality of Sachet Water Produced and Sold in Maiduguri, North East Nigeria

Sachet water is the predominant source of packaged drinking water for low-income urban populations across Nigeria, yet its microbiological and physicochemical safety is inconsistently monitored by regulatory authorities, particularly in conflict-affected regions. This study evaluates the physicochemical and microbial quality of sachet water samples from twelve registered and unregistered producers operating in Maiduguri, Borno State, North East Nigeria. Physicochemical parameters measured include pH, electrical conductivity, total dissolved solids, turbidity, nitrate, sulphate, and hardness. Microbial analysis determines total aerobic plate count, total coliform, and Escherichia coli counts using the membrane filtration technique. Samples are collected from production sites and retail points to compare contamination at source versus point-of-sale. Results are evaluated against the Nigerian Industrial Standard for packaged drinking water and World Health Organization microbial guidelines. Statistical comparisons between registered and unregistered producer categories are performed using the Mann-Whitney U test. The study is expected to reveal higher microbial contamination among unregistered producers, with total coliform counts exceeding the permissible zero limit for packaged water. Findings provide evidence for improved post-market surveillance by the National Agency for Food and Drug Administration and Control and support health education initiatives in the North East. Keywords: sachet water, microbial quality, physicochemical parameters, Maiduguri, drinking water safety