Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa.
Ecotoxicology. 2013 Mar;22(2):331-8. doi: 10.1007/s10646-012-1029-6. Epub 2012 Dec 11.
South Africa is an important platinum mining country which results in environmental impacts due to the construction of tailing disposal facilities (TDFs). It is unclear what the effects of ageing are on the ecotoxicity of TDFs and whether it increases or decreases over time. The aim of this study was to determine the ecotoxicity of differently aged TDFs by investigating earthworm (Eisenia andrei) responses viz. growth, reproduction, neutral red retention times (NRRT) and tissue metal concentrations. Further, to evaluate the status of these in terms of a geoaccumulation index (I(geo)), pollution index and integrated pollution index. Results indicated that earthworms showed reduced reproductive success (hatchlings per cocoon) and decreased NRRT in all the sites. Juveniles per cocoon between all of the different treatment groups were; control (2.83 ± 0.54) > site 2 (20 years old; 1.83 ± 0.27) > sites 1 and 3 (40 years old; 1.06 ± 0.15 and 6 years old; 0.88 ± 0.39). This might be ascribed to the elevated levels of Cr (±200 to 1,166 μg g(-1)) and Ni (±100 to 316 μg g(-1)) in all of the sites. Earthworms did not bioaccumulate metals with bioconcentration factors for all the different treatments <0.01. Studies like these could be useful when establishing a ranking of TDFs in the future to provide legislative institutions with an indication of the environmental liabilities of platinum mines.
南非是一个重要的铂金矿业国家，由于尾矿处置设施（TDF）的建设，导致环境受到影响。目前尚不清楚老化对 TDF 生态毒性的影响，以及随着时间的推移，这种影响是增加还是减少。本研究旨在通过调查蚯蚓（Eisenia andrei）的反应，即生长、繁殖、中性红保留时间（NRRT）和组织金属浓度，确定不同年龄 TDF 的生态毒性。此外，还评估了这些 TDF 在地质累积指数（I(geo)）、污染指数和综合污染指数方面的状况。结果表明，所有地点的蚯蚓繁殖成功率（每茧幼虫数）和 NRRT 均降低。所有不同处理组的幼体数为：对照组（2.83±0.54）> 20 年场地（20 岁；1.83±0.27）> 40 年场地和 6 年场地（40 岁；1.06±0.15 和 6 岁；0.88±0.39）。这可能是由于所有地点 Cr（±200 至 1166μg g(-1)) 和 Ni（±100 至 316μg g(-1))）水平升高所致。所有不同处理组的蚯蚓生物浓缩因子均<0.01，表明其金属没有生物积累。当未来建立 TDF 排名时，此类研究可能有助于为立法机构提供有关铂金矿环境负债的指示。
