Health Risk Assessment of Heavy Metals in Sachet Water in Federal Capital Territory of Nigeria

The physical, chemical and bacteriological properties of fifteen (Groups A-O) selected sachet water brands sold in Gwagwalada, Nigeria, were analyzed and compared with WHO standard. Physical examination of the samples showed 100% compliance in term of product names, manufacturer’s addresses and NAFDAC registration, but 0% compliance on manufacturing date, expiry date, batch number and mineral composition. Results showed that Fluoride (Groups B=1.53mg/l, N=1.51mg/l); Residual chlorine (Groups B=0.32mg/l, K=0.22mg/l, N=0.26mg/l, O=0.22mg/l); Fe (Groups B=0.4mg/l, F=2.5mg/l, H=2.6mg/l, I=3.2mg/l, J=1.3mg/l, L=0.4mg/l) and Pb (Groups F=0.013mg/l, I=0.012mg/l) had concentrations above the acceptable limits in some sachet water brands, while Ca concentration is high in all brands (Groups A-O). Cd, Total coliforms and faecal coliforms were not detected in any of the sachet water brands. ANOVA and student t-tests at significance level P≤0.05 indicates no statistically significant variation in concentration of tested parameters across the different water samples; also, there is no significant difference between concentration of parameters in individual Groups (A-O) of the water samples and WHO standard. Non-carcinogenic health risk assessment based on concentrations of HMs in the water samples ingested orally indicates that the CDI and HQ were higher in the children compared to adults exposed to the same sachet water brands. Hazard Index (HI) was in the order Ca>Na>Cu>Fe>Cr>Mg>Pb>Zn>Ni>Mn for both adult and children, with Ca, Na, Cu, Fe, Cr and Mg having HI>1 for adults while the children had HI>1 for Ca, Na, Cu, Fe, Cr, Mg and Pb. Cumulative HI of 1489.47 and 2478.48 were obtained for adults and children respectively, with Ca contributing most towards the exposure to non-cancer risks. These results indicate severe exposure to non-carcinogenic health risk for both populations, with the children being more disposed towards non-cancer risks. The result is quite worrisome and presents the need to further collect data for the assessed