Natural Resources and the Environment, CSIR, Stellenbosch, South Africa.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2011;46(10):1129-37. doi: 10.1080/10934529.2011.590729.
The present paper is a review on the status of mercury (Hg) as a pollutant in South African aquatic ecosystems. Spatial patterns of Hg distribution and bioaccumulation in water resources were investigated by collecting and analyzing multimedia samples for physiochemical and Hg-species determination from 62 sampling sites. The data presented showed a wide range in concentrations, which was expected given the array of environmental parameters, water chemistry and sources of Hg. Generally, higher Hg concentrations were measured in environmental compartments impacted by the major anthropogenic Hg sources which, in South Africa, are largely represented by emissions from coal-fired power stations (i.e. Olifants and Upper Vaal WMAs) and artisanal gold mining (i.e., Inkomati WMA). Ancillary water quality parameters (e.g. pH, temperature, DOC, EC and nutrients) were measured and regressed with the measured Hg concentrations to determine which environmental parameters most influenced regional Hg concentrations. The TotHg (sed) and DOC concentrations were identified as important factors controlling TotHg (aq), while TotHg(sed) were correlated to TotHg (aq). This result is indicative of the combined effects of sediment settling and resuspension in the aquatic environment. In contrast, MeHg (aq) was not correlated to DOC. MeHginvert were correlated to MeHg (sed), while MeHg (fish) were correlated to MeHg (aq) and water quality variables (chlorides--Cl(-) and electrical conductivity--EC). A steady progress has been made in Hg research in South Africa. However, despite the substantial knowledge about Hg toxicity, there are still considerable knowledge gaps on the fate and transport of Hg. Hence, further environmental and human health studies are proposed.
本论文综述了汞（Hg）作为南非水生生态系统污染物的现状。通过收集和分析来自 62 个采样点的多介质样品，对水资源中 Hg 的分布和生物积累进行了研究，以进行理化和 Hg 形态测定。所提供的数据显示了浓度范围很广，考虑到环境参数、水化学和 Hg 源的多样性，这是可以预期的。一般来说，在受主要人为 Hg 源影响的环境隔室中测量到更高的 Hg 浓度，在南非，这些 Hg 源主要来自燃煤电厂（即 Olifants 和 Upper Vaal WMAs）和手工采金（即 Inkomati WMA）的排放。还测量了辅助水质参数（例如 pH 值、温度、DOC、EC 和养分），并与测量的 Hg 浓度进行了回归，以确定哪些环境参数对区域 Hg 浓度影响最大。TotHg（sed）和 DOC 浓度被确定为控制 TotHg（aq）的重要因素，而 TotHg（sed）与 TotHg（aq）相关。这一结果表明了在水生环境中沉积物沉降和再悬浮的综合影响。相比之下，MeHg（aq）与 DOC 不相关。MeHginvert 与 MeHg（sed）相关，而 MeHg（fish）与 MeHg（aq）和水质变量（氯化物-Cl(-)和电导率-EC）相关。南非的 Hg 研究取得了稳步进展。然而，尽管对 Hg 毒性有了大量的了解，但 Hg 的命运和迁移仍然存在相当大的知识空白。因此，建议进行进一步的环境和人类健康研究。
