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Soil profiles at five automobile mechanic waste dumps in Port-Harcourt, Nigeria were investigated to assess the spatial distribution, chemical speciation, and likely mobility of Cd, Cu, Pb, Zn, Cr and Ni in the soil as a function of the soil properties. A sequential fractionation protocol was used that generated six different fractions into which soil metal could partition. Cadmium was associated with non-residual fractions at surface horizons, but at lower depths it was in the residual fractions. Copper and Cr partitioned into organic and residual fractions, while Pb was associated with an Fe-Mn oxide fraction and the residual fractions. Zinc in surface horizons partitioned into an Fe-Mn oxide fraction and a fraction that captured carbonate-bound species, but in subsurface horizons, it was mainly in the residual fractions. Ni was predominantly found in the residual fractions. Mobility factors were calculated, and their values tended to decrease with increasing profile depth, indicating that these metals are relatively mobile in the surface horizons compared the subsurface except for chromium in the 15-30 cm depths. The mobility factors for the heavy metals follow the order: Cd > Zn > Pb > Cu > Cr > Ni. The results suggest that there is serious contamination hazard with Cd, Pb, and Zn in the soil profiles.

The concentrations of 12 metals (Cd, Pb, Ni, Cr, Cu, Co, Fe, Mn, Zn, Ca, Mg and K) in 13 classes of alcoholic beverages were determined by atomic spectrometry after HNO 3 /H 2 O 2 digestion. The mean concentrations of metals (μg mL À1 ) in these alcoholic beverages varied in the ranges 0.01-0.04, 0.02-0.24, 0.04-0.13, 0.01-0.28, 0.01-0.77, <0.001-0.12, 0.28-1.48, 0.004-0.33, 0.10-1.02, 1. 43-162.86, 0.26-25.46 and 0.49-322.58 for Cd, Pb, Ni, Cr, Cu, Co, Fe, Mn, Zn, Ca, Mg and K respectively. The concentrations of metals found in these particular alcoholic beverages were below the International Statutory Limits for metals in alcoholic beverages. The estimated daily intake of the metals based on a per capita consumption of 3.6 L per annum pure alcohol was <3% of the tolerable daily intake of each metal. The individual and combined target hazard quotients of the metals were <1, indicating no long-term health concerns from the consumption of these alcoholic beverages based on their metal content alone.

The characteristic levels of heavy metals (Cd, Cr, Cu, Pb, Ni and Zn) of soil profiles of automobile mechanic waste dumps were studied. The concentration of heavy metals decreased with the depth of the profile and lateral distance from the dumpsites. The levels found in this study exceeded background concentrations and limits for agricultural and residential purposes. The distribution pattern of heavy metals in the soil profiles were in the following order Pb > Zn > Cu > Cd > Ni > Cr. The mechanic waste dumps represent potential sources of heavy metal pollution to environment. The elevated levels of heavy metals in these soil profiles constitute a serious threat to both surface and groundwater.

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A BS T RA C T:This communication presents the results of preliminary investigation of the characteristic levels of heavy metals in surface soils of an oilfield in the Niger Delta. The results indicate higher concentration of the following metals: Cd, Pb, Cu; Ni, Zn, Cr, Mn and Hg in soils around the gas plant than the pipeline areas. There is a significant temporal and spatial variation in the concentrations of the heavy metals. Samples collected during the wet season showed lower concentrations of heavy metals. The distribution pattern of heavy metals follows the following order Fe> Mn> Zn> V> Cr> Pb> Cu> Ni> Cd> Hg> As. The soils around the oilfield could be considered unpolluted since the concentrations of the metals fit into background levels and concentrations found in natural and agricultural soils. Since metal build up is a gradual process, farmland, fishing ponds and water bodies closer to these facilities will be at risk of heavy metal pollution over time.

The concentrations of nine metals (Cd, Pb, Ni, Cr, Co, Cu, Fe, Mn and Zn) were determined in lip sticks, lip glosses, lip balms, eye pencils, eyeliners, eye shadows, blushes, mascaras and face powders. The study was aimed at providing information on the risk associated with human exposure to metals in these facial cosmetic products. The concentrations of metals in the samples were measured by atomic absorption spectrometry after digestion with a mixture of nitric acid, hydrochloric acid and hydrogen peroxide. The mean concentrations of metals in these facial cosmetics ranged from 3.1 to 8.4 μg g−1 Cd, 12–240 μg g−1 Pb, 9.1–44 μg g−1 Cr, 18–288 μg g−1 Ni, 1.6–80 μg g−1 Cu, 7.9–17 μg g−1 Co, 2.3–28 mg g−1 Fe, 12–230 μg g−1 Mn, and from 18 to 320 μg g−1 Zn. The concentrations of Ni, Cr and Co were above the suggested safe limit of 1 μg g−1 for skin protection, while Cd and Pb were above the Canadian specified limits. The systemic exposure dosage (SED) values for these metals obtained from the use of these facial cosmetic products were below their respective provisional tolerable daily intake (PTDI)/or recommended daily intake (RDI) values. The margin of safety values obtained were greater than 100 which indicated that the concentrations of the metals investigated in these facial cosmetics do not present considerable risk to the users except in the case of face powders.