Kemp M, Wepener V, de Kock K N, Wolmarans C T
School of Biological Sciences, North-West University, Potchefstroom, South Africa.
Bull Environ Contam Toxicol. 2017 Dec;99(6):662-667. doi: 10.1007/s00128-017-2201-8. Epub 2017 Nov 9.
The Marico River is relatively unaffected by anthropogenic activities. However, metal concentrations-mainly from natural sources-occasionally exceed environmental quality guidelines. Macroinvertebrates are capable to react to these metals through processes such as the induction of metallothioneins (MTs). The aims of this study were to determine whether the induction of MTs can be used as indicator of natural metal exposure in not anthropogenically impacted systems and whether there are relationships between metal concentrations in water, sediment and macroinvertebrates and concomitant MT levels. Positive correlations were found between metals in sediment and macroinvertebrates, while there were no correlations between metal concentrations in water and macroinvertebrates. Even in a not anthropogenically impacted system, a positive correlation existed between trace metal bioaccumulation (e.g. Ni, Pb, Zn) in macroinvertebrates and the induction of MTs. There were, however, no correlations between MTs and bioaccumulation of earth metals (e.g. Al, Fe, Mn, Ti).
马里科河相对较少受到人为活动的影响。然而，金属浓度（主要来自自然源）偶尔会超过环境质量准则。大型无脊椎动物能够通过诸如诱导金属硫蛋白（MTs）等过程对这些金属做出反应。本研究的目的是确定MTs的诱导是否可作为非人为影响系统中自然金属暴露的指标，以及水、沉积物和大型无脊椎动物中的金属浓度与相应的MT水平之间是否存在关系。在沉积物中的金属与大型无脊椎动物之间发现了正相关，而水中的金属浓度与大型无脊椎动物之间没有相关性。即使在非人为影响的系统中，大型无脊椎动物中的痕量金属生物累积（如镍、铅、锌）与MTs的诱导之间也存在正相关。然而，MTs与碱金属（如铝、铁、锰、钛）的生物累积之间没有相关性。
