Heavy metal profile with health risk peculiarities in Enugu State and their long-term challenges in drinking water.

Health authorities are particularly concerned about water security in Enugu, southeast Nigeria and heavy metal (HM) pollution. The HM profiles of 51 samples collected from 17 different commercial bottled water brands in Enugu were examined using an flame atomic absorption spectroscopy. Cd, Cr, Cu, Pb, Ni, and Zn had mean values of 0.15 ± 0.03, 0.03 ± 0.02, 0.16 ± 0.03, 0.13 ± 0.02, and 0.02 ± 0.01 mg/L, respectively. The highest levels of Pb2+ were 0.27 mg/L in Exalté, Ni2+ 0.26 mg/L in Jasmine, Cd2+ 0.36 mg/L in Ezbon, Cr3+ 0.07 mg/L in Trinity, Cu2+ 0.04 mg/L in Bigi, and Zn2+ 0.02 mg/L in Aquarapha. The amounts of Cr, Cu, and Zn were below the allowable limits; nevertheless, the Pb content in eight bottled water samples exceeded both the Nigerian and World Health Organization (WHO)/U.S. Environmental Protection Agency (USEPA) permissible limits. The Cd2+ and Ni2+ levels in the 11th and 4th bottled water samples were above the WHO/USEPA-approved limits. Statistical evaluation revealed significant differences in the amounts of HM ions in the samples (p < 0.05). The findings indicated that concentration levels of Cd2+ Ni2+, and Pb2+ pose a public health concern that needs to be addressed due to potential risk to consumer health.

Environmental and health implications of trace metal concentrations in street dusts around some electronic repair workshops in Owerri, Southeastern Nigeria.

Assessment of trace metal concentrations in street-deposited sediments around some selected electronic repair workshops in Owerri, Imo State, Nigeria, was carried out. The objective of the study was to determine the concentrations of trace metals, namely nickel (Ni), chromium (Cr), lead (Pb), copper (Cu), cadmium (Cd), and zinc (Zn), in surface dusts from streets within some electronic repair workshops in Owerri, Imo State, Nigeria. Dust samples were collected from seven locations within the month of January 2014 during the dry season when the onset of dust was high in the area. The samples were air-dried, sieved, and digested in aqua regia, with the concentrations of trace metals determined with atomic absorption spectroscopy, Agilant FS 240AA model (USA). Results of the study revealed all the trace metals assessed except Cr in dust sample from Aladinma (ALA). Though elevated concentrations of Zn and Cu were observed in all the sampled locations, the concentrations did not exceed the Dutch intervention values. Risk assessment of the heavy metals showed high average daily dose (ADD) of the heavy metals for children and adults at New Market 2 (NMK2), New Market 1 (NMK1), and Tetlow (TEL), which could be attributed to the presence of electronic repair workshops and activities of electronic scrap dealers within these areas. It was observed that the values of hazard quotient (HQ) were less than 1, while that of hazard index (HI) were all below 1-5, indicating that the heavy metals pose no health risk to adults and children in the environment. However, there may be potential danger if the waste generated from the electronic repair workshops and electronic scrap dealers are not properly disposed and managed.