Assessing the impacts of artisanal mining on the quality ofvf South-western Rivers System in Ghana.

Artisanal small-scale mining has been part of Ghana's history, but recent public outcry on the devastating impacts of the phenomenon on water bodies, due to expansion in the sector, has led to clamp downs by various governments on the activity. This has called for evaluation of the water quality of the South-western Rivers System, which are small-scale mining endemic areas. Thirty-five river samples were collected in July 2018 and were analyzed for physico-chemical parameters using procedures outlined in the Standard Methods for the Examination of Water and Wastewaters. The results revealed that the rivers are polluted with Fe and Cu, accompanied by very high levels of turbidity (mean = 488 NTU) and total suspended solids (TSS) (mean = 382 mg/L). NH3-N, PO4-P, BOD, and DO levels indicated mild pollution in the waters. Pollution of the rivers is attributable to impacts of artisanal small-scale mining, surface run-off as a result of high intensity rainfall, anthropogenic (indiscriminate waste disposal) and geogenic factors such as dissolution of minerals from the soil zone. It was observed that, if not strictly regulated, turbidity and TSS levels arising mainly from illegal small-scale mining activities could lead to shutdowns of a number of Ghana Water Company Limited treatment plants, leading to water supply challenges in the study area.

Exposure to toxicants in soil and bottom ash deposits in Agbogbloshie, Ghana: human health risk assessment.

Recycling of e-waste using informal or crude techniques poses serious health risk not only to the workers but also to the environment as whole. It is against this background that this paper sought to measure health risk faced by informal e-waste workers from exposure to toxicants such as lead, cadmium, chromium, copper, arsenic, tin, zinc and cobalt via oral and dermal contact with bottom ash and soil. Using random sampling techniques, 3 separate sites each (where burning and manual dismantling of e-wastes are usually carried) were identified, and a total of 402 samples were collected. The samples were analysed using standard methods for chemical analysis prescribed by the American Water Works Association (AWWA). Concentrations of Pb, Cd, Cr, Cu, As, Sn, Zn and Co in bottom ash samples from location ASH1 are 5388 ± 0.02 mg/kg (Pb), 2.39 ± 0.01 mg/kg (Cd), 42 ± 0.05 mg/kg (Cr), 7940 ± 0.01 mg/kg (Cu), 20 ± 0.07 mg/kg (As), 225 ± 0.04 mg/kg (Sn), 276 ± 0.04 mg/kg (Zn) and 123 ± 0.04 mg/kg (Co), while concentrations of the aforementioned toxicants in soil samples at location ASG1 are as follows: 1685 ± 0.14 mg/kg (Pb), 26.89 ± 0.30 mg/kg (Cd), 36.86 ± 0.02 mg/kg (Cr), 1427 ± 0.08 mg/kg (Cu), 1622 ± 0.12 mg/kg (As), 234 ± 0.25 mg/kg (Sn), 783 ± 0.31 mg/kg (Zn) and 135 ± 0.01 mg/kg (Co); used as input parameters in assessing health risk faced by workers. The results of cancer health risk faced by e-waste workers due to accidental ingestion of As in bottom ash at ASH1 is 4.3 × 10-3 (CTE) and 6.5 × 10-2 (RME), i.e. approximately 4 out of 1000 e-waste workers are likely to suffer from cancer-related diseases via central tendency exposure (CTE parameters), and 7 out of every 100 e-waste worker is also likely to suffer from cancer cases by reasonable maximum exposure (RME) parameters, respectively. The cancer health risk results for the other sampling sites were found to have exceeded the acceptable USEPA cancer risk value of 1 × 10-4 to 1 × 10-6 (i.e. 1 case of cancer per every 10,000 people to 1 case of cancer per every 1,000,000 people). The non-cancer health risk results for all the toxicants were higher in all the locations for both adult and children working the e-waste site. From the findings of this study, the government of Ghana has to immediately put in place policies that would address the safety of the e-waste workers as well as protect the environment.