BackgroundThis study assessed lead, cadmium, and nickel level in food crops, fruits and soil samples from Ohaji and Umuagwo and Owerri in South Eastern Nigeria and estimated the potential health risks of metals. Samples were washed, oven-dried at 70–80°C for 24 h and powdered. Samples were digested with perchloric acid and nitric acid. Metals were analysed with Unicam Atomic Absorption Spectrophotometer.ResultThe concentration of Pb, Cd, and Ni in Ohaji exceeded the maximum allowable concentrations for agricultural soil as recommended by EU. Lead, Cd, and Ni in the food crops were highest in Oryza sativa, Glycine max, and Pentabacta microfila respectively. Highest levels of Pb, Cd, and Ni, in fruits were detected in Canarium schweinfurthii, Citrus reticulata, Ananas comosus respectively. The true lead and cadmium intake for the rice based meal were 3.53 and 0.034 g/kg respectively. Whereas the true intake of lead and cadmium for the cassava based meal were 19.42 and 0.049 g/kg respectively.ConclusionLocal food stuff commonly available in South Eastern Nigeria villages may contribute to the body burden of heavy metal. This is of public health importance.

Most of the metal levels were above US EPA Maximum Contaminant Level MCL indicative of water pollution which may be of public health importance, and we, therefore, recommend water-quality monitoring.

Rain samples were collected from Warri and Port Harcourt, two major oil-producing cities of Nigeria in April-June, July-August, and September-October 2005 and 2006. Awka, a “non-oil” city was used as control. Samples were collected from three points, using clean plastic basins fastened to a table, 2 m above ground level and 115 m away from tall buildings and trees. Water samples were filtered and acidity determined using digital pHmeter. The results show that the rain samples were acidic. The pH values for the 2 years under study show that the rainfall in Warri was more acidic than that of Port Harcourt. Oil exploration and other anthropogenic sources may be responsible for the acid rain in the Niger Delta region of Nigeria.

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This study investigated the effect of refinery effluents on different sources of potable water supply in two areas of Niger Delta contiguous host and impacted on communities of Delta State, Nigeria (surface water, shallow well water and borehole water) in Ekpan, its adjoining communities and creeks. Since open and underground water bodies are regarded as final recipient of most environmental pollutant, we sought through the study to provide data on pollutant load of potable water supply of the study area. Cadmium, chromium, lead and manganese were determined using Atomic Absorption spectrophotometry; physico-chemical parameters such as nitrate,nitrite, pH, Biological oxygen demand BOD, Total hardness TH, salinity and electrical conductivity EC were all determined using their standard methods. Surface water of Aja-Etan and Ijala had highest levels of cadmium (1.45±0.01 and 1.20 ± 0.0(mg/l), that of ifie-kporo and Ekpan had highest lead (1.00 ± 0.01mg/l). Ekpan borehole water is more acidic (4.79± 0.01) than others. Agigba and Ajamimogha surface water had highest level of manganese (2.40 ± 0.03 and 2.20 ± 0.03mg/l). With the exception of Ekpan shallow well, BOD and hardness were in highest concentration in surface water. Some of the parameter were above WHO standards and USEPA maximum contaminant level MCL.