Heavy Metal Concentrations and Microbial Quality of Sachet Water Marketed in Rivers North Senatorial District, Rivers State, Nigeria

Abstract

This study aimed at evaluating the public-health consequences of sachet bottled water products that are in circulation in the Rivers North Senatorial District, of Rivers State, Nigeria. A random sample of thirty-six sachet-water samples was chosen out of an eclectic mix of sellers in and around the headquarters of the sampled local government area. Ten trace metal constituents, including Chromium, Cadmium, Lead, Mercury, Nickel, Zinc, Iron, Copper, Manganese and Cobalt were determined analytically by Atomic Absorption Spectrometry (AAS) along with measurements of ten physicochemical indices. Bacteriological examination used a membrane filtration procedure to identify and count fecal coliform populations. The concentrations of heavy metals in the consumed water were the determinants of health risk appraisal. Findings showed that the majority of the heavy-metals were within the acceptable limits established by the international health organizations. But in the case of the physicochemical parameters, pH values were different among the samples with some being slightly lower than the recommended range of 6.5-8.5 (WHO and NSDWQ). It is worth noting that sample IK4 (Falos) had a pH of 4.3 which could be considered as not complying with drinking-water standards. The overall dissolved solids (TSS) were between 10 and 95 mg/L -1, and turbidity varied, with sample IK1 (Esleno) having the most turbidity of 5.5 NTU. Four bacterial isolates were obtained, namely, Staphylococcus sp., Pseudomonas sp., Enterobacter sp., and Escherichia sp. Non-carcinogenic health risk was measured by indices like the estimated daily intake, target hazard quotient and projection of carcinogenic risk, particularly in heavy metals like Cadmium, Lead, Nickel and Chromium. The research suggests that there should be frequent inspections of sachet-water plants to make sure that they are adhering to the local and international water-quality standards.