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ObjectivesThis study examined the spatial distribution and the extent of soil contamination by heavy metals resulting from primitive, unconventional informal electronic waste recycling in the Agbogbloshie e-waste processing site (AEPS) in Ghana.MethodsA total of 132 samples were collected at 100 m intervals, with a handheld global position system used in taking the location data of the soil sample points. Observing all procedural and quality assurance measures, the samples were analyzed for barium (Ba), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb), and zinc (Zn), using X-ray fluorescence. Using environmental risk indices of contamination factor and degree of contamination (Cdeg), we analyzed the individual contribution of each heavy metal contamination and the overall Cdeg. We further used geostatistical techniques of spatial autocorrelation and variability to examine spatial distribution and extent of heavy metal contamination.ResultsResults from soil analysis showed that heavy metal concentrations were significantly higher than the Canadian Environmental Protection Agency and Dutch environmental standards. In an increasing order, Pb>Cd>Hg>Cu>Zn>Cr>Co>Ba>Ni contributed significantly to the overall Cdeg. Contamination was highest in the main working areas of burning and dismantling sites, indicating the influence of recycling activities. Geostatistical analysis also revealed that heavy metal contamination spreads beyond the main working areas to residential, recreational, farming, and commercial areas.ConclusionsOur results show that the studied heavy metals are ubiquitous within AEPS and the significantly high concentration of these metals reflect the contamination factor and Cdeg, indicating soil contamination in AEPS with the nine heavy metals studied.

The objective of this study is first, to investigate the level of heavy metals in soils from Agbogbloshie e-waste processing site (AEPS), the degree at which these heavy metals contaminate the area and finally, to assess the carcinogenic and non-carcinogenic health risk of heavy metals on workers and residents in around the AEPS. 132 soil samples were collected from the study area and the samples analyzed for Ba, Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn heavy metals after appropriate preparations were made. Results of the analysis showed mean concentrations of Cd, Cr and Ni considered as carcinogenic were lower than permissible levels of Dutch and Canadian soil standards. Mean concentrations however of Cu, Pb and Zn were between 100% and 500% higher than the permissible levels. Assessment of the degree of Contamination indicated Ni<Ba<Co<Cr<Zn<Hg<Cu<Cd<Pb in an increasing order as contributing to the degree of contamination with according to the degree of contamination index the burning, dismantling, residential and commercial considered as very highly contaminated. The health risk analysis of individual heavy metals in soil indicated non-carcinogenic risk of Cr, Hg and Pb with hazard index above the safe level of 1 in the burning and dismantling areas and as such could trigger neurological and developmental disorders in children less than six (6) years.

Environmental studies have revealed significant contributions of vehicular exhaust emissions to high pollution levels in urban dwellings. The levels and sources of heavy metal contaminations of some major roads in Accra have been investigated in this work. Street dust samples collected from four major roads in Accra (Mallam Junction‐Weija road, John Teye‐Pokuase road, Tema Motorway and Tetteh Quarshie Interchange in Accra) were analysed for their elemental concentrations using energy‐dispersive X‐ray fluorescence. Twenty elements were identified: K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Br, Rb, Sr, Y, Zr and Pb. Significant concentration levels were obtained for K, Ca, Ti, V, Cr, Mn, Fe, Cu, Zn, Br, Rb, Sr, Y, Zr and Pb in all the samples and were used for the source identification. Enrichment factors and principal component analysis were used to verify the anthropogenic contribution to road dust. Results obtained for the enrichment factors showed moderate enrichment for V, Cr and Cu, while Zn, Br, Zr and Pb were significantly enriched. Principal component analysis identified four sources and their contributions to the elemental contents in the road dust. Natural crust, brake wear, tyre wear and vehicle exhaust emission were the four sources identified. The contribution of vehicular non‐exhaust emissions to heavy metal contamination in the road dust was found to be greater than that of exhaust emissions. Copyright © 2012 John Wiley & Sons, Ltd.

Elevated exposure to Ultra-Violet Radiation (UVR) from the sun has led to adverse effects on human skin and foods, and therefore, the need for materials that offer resistance to Ultra-Violet (UV) penetration for protection. Some building window and non-window-materials, car-glasses, Linear Low Density Polyethylene (LLDPE) and Polyethylene Terephthalate (PET) rubber and plastic materials have been investigated to determine their transparencies and suitability for use as shields against UVR. These were studied by directly measuring scattered solar radiation through the optical window of a spectrometer and then measuring the scattered light when the window was completely covered with the material to be examined. Wavelengths of light that were not absorbed when sunlight was incident on the samples and the transmitted intensity of sunlight at each wavelength through each sample as compared to the transmitted intensity through air were determined in the UVB and UVA spectral regions. The results showed that the building window-glasses were opaque to UVB but transparent to UVA while the non-window-glasses exhibited transparency in the UVB and UVA spectral regions. The car-glass (laminated), used as windscreen, was opaque to UVB and UVA while the side-glass (non-laminated) was opaque to UVB but transparent to UVA. Perspex, sometimes used as an alternative to windscreen and side-glass in cars, exhibited transparency in UVB and UVA spectral regions. The LLDPE materials used for food storage were transparent to UVB and UVA while the PET plastic materials used for water, fruit juice and beverage storage was opaque to UVB but transparent to UVA.