Exposure of children to heavy metals from artisanal gold mining in Nigeria:evidences from bio-monitoring of hairs and nails

In recent times,there had been reported cases of Pb poisoning in Anka gold mining area,Northwest Nigeria.Therefore,this study was carried out to determine the extent of bioaccumulation of heavy metals in the hairs and nails of children in the area.Forty samples(twenty nails and twenty hairs)samples were collected from ten boys and ten girls of ages 5–9 residing in the area.To ascertain the sources of heavy metals in children,15 soils samples,15 groundwater samples,5 samples of mine tailings,and 5 plants samples were collected.Hair and nails of the subjects were collected using internationally acceptable techniques.All samples were kept in uncontaminated ziplock bags prior to laboratory preparation and analysis.The samples were cleaned using nonionic detergent(triton X-100)and deionized water.The hairs and nails were digested with 10 mL of 6:1 mixture of nitric acid and perchloric acid.The soils,mine tailings,and plants were air-dried at room temperature,sieved,and chemically digested using the aqua regia method.The concentrations of metals in all the samples were determined using highperformance liquid chromatography–inductively coupled plasma–mass spectrometry.Statistical analysis was employed to unravel potential sources of metals in the media.Results showed that heavy metals in children of the area are above results from similar studies and pathological ranges for heavy metals in hairs and nails.Also,heavy metals in environmental media are above the recommended standards.Multivariate analysis showed that the metals are mainly from mining and other anthropogenic sources.Results of correlation between heavy metals in hairs and nails with those in geological samples revealed that heavy metal that bioaccumulates in the children of this area are mostly from contaminated environmental media.It is recommended that complete remediation and effective health education be carried out in the area.

Impact of Sand Mining and Sea Reclamation on the Environment and Socioeconomic Activities of Ikate and Ilubirin Coastal Low Income Communities in Lagos Metropolis, Southwestern Nigeria

Land reclamation is gradually posing negative impact on man due to unplanned urbanization. A study was carried out on impact of land reclamation through sand mining of coastal communities in Ikate and Ilubirin in Lagos, Nigeria. Ten waters (8 surface and 2 groundwater sources), 10 soil samples and air were collected and taken for analysis. Results of water revealed concentrations lower than WHO (2017) and SON (2007) standards. Soil/sediment with average crustal value revealed Pb and Cd above standard values, which is attributed to anthropogenic influence on soils. Quality of air in the study was mainly particulate matter arising from the sea and reclaimed land in the surroundings of the environment with the highest Total Suspended Particulate of 0.8 mg/m3 in sulfur dioxide. This explains corrosion found on the roofs of the communities. Therefore, in the development planning adequate precautions should be put in place to avert environmental degradation.