Frank K. Nyame

Policy challenges on mercury use in Ghana's artisanal and small-scale mining sector

Mercury use in Ghanas Artisanal and Small-scale Mining (ASM) sector is a growing problem owing to the increasing numbers of people involved, locations of operation, extent of possible contamination of the natural environment and its impact on human health. For over two decades, many local and internationally-coordinated initiatives undertaken to mitigate its harmful effects in ASM communities have been mostly unsuccessful due to absence of alternative options acceptable for gold recovery and inadequate awareness of the short- and long-term health effects of mercury use. This paper examines major policy challenges in minimising mercury use in Ghanas ASM sector, arguing that a coordinated, integrated and sustained approach offers better promise in tackling the problem.

Heavy metals concentration and distribution in soils and vegetation at Korle Lagoon area in Accra, Ghana

Abstract The call for reclamation of land around Korle Lagoon in Accra, Ghana, where burning of e-waste and cultivation of vegetables takes place, makes risk assessment of heavy metal contaminations important. This study aimed at evaluating the levels and risk of heavy metal contamination in soils and vegetation around the Korle lagoon area in Accra. Geoaccumulation index, enrichment factor and pollution load index were determined to assess the risk of contamination. The levels and distribution of nine heavy metals (Pb, Hg, Cd, As, Zn, Sn, Ni, Cu and Cr) in soil (0–20 cm) and common vegetation (Panicum maximum, Imperata cylindrica, Lactuca sativa and Hibiscus sabdariffa) from the area using Atomic Absorption Spectrometer (AAS) were assessed. The area was divided into five sites, namely; the e-waste site (S1), gardens area (S2), recreational area (S3), reclaimed area (S4) estuary (S5) and the control (S6) which was about 700 m away. Soil analysis showed that the concentration of Pb (184.44 mg/kg), Cd (103.66 mg/kg), Cu (202.99 mg/kg), Ni (72.00 mg/kg) and Sn (705.32 mg/kg) at S1 exceeded their WHO/FAO thresholds for agricultural soils. Concentrations of heavy metals in soils from the e-waste site were significantly different (p < 0.01) from the other sites. High accumulations of heavy metals were also observed in the plants samples collected from the study sites, with the concentrations of Cu, Pb, Ni and Cd exceeding their acceptable limits. Laws against open burning of e-waste should be enforced and animals should be restricted from grazing on the forage.