Centre for Environmental Sciences, Faculty of Engineering and the Environment, Lanchester Building, University of Southampton, University Rd., Highfield, Southampton, Hampshire SO17 1BJ, UK.
Centre for Environmental Sciences, Faculty of Engineering and the Environment, Lanchester Building, University of Southampton, University Rd., Highfield, Southampton, Hampshire SO17 1BJ, UK.
Sci Total Environ. 2014 Mar 1;473-474:391-7. doi: 10.1016/j.scitotenv.2013.11.136. Epub 2013 Dec 28.
Poole Harbour is typical of many heavily anthropologically impacted semi-enclosed estuarine coastal areas under pressure from metal pollution across the world. This study examined the physiological significance of metal burdens within that sensitive area, and assessed the potential use of metallothionein (MT) concentrations in two organisms: the common cockle (Cerastoderma edule) and the Mermaid's glove sponge (Haliclona oculata) for mapping the spatial extent of the biological response to metal contamination. A spectrophotometric method was applied for detection of MT in the bivalve, and for the first time to detect MT in sponges. The results show that while some metal concentrations in cockle and sponge tissues and in their surrounding environment (water and sediment) could be related to sources of metal contamination, MT values in the soft tissue of cockles and whole tissue of sponges are not. No relation could be found between MT in both cockles and sponges, and any of the tested metals (As, Cd, Cr, Cu, Pb, Hg, Ni, Ag, Sn, Zn). Furthermore, some of the lowest MT concentrations were detected in heavily polluted areas, indicating that MT concentrations in tested organisms are not exclusively associated with metal concentrations, as other environmental factors could affect induction of this protein. Organisms probably have a high tolerance to metal contamination and chronic exposure to a high level of contamination resulted in developing a variety of detoxification mechanisms. Results indicate that further study of metal stress in this type of ecosystem may need to examine other indicator species and/or apply a different biomonitoring technique.
普尔港是世界上许多受到重金属污染的半封闭河口沿海地区的典型代表，这些地区受到人类活动的强烈影响。本研究调查了该敏感区域内金属负荷的生理意义，并评估了两种生物（普通贻贝（Cerastoderma edule）和美人鱼手套海绵（Haliclona oculata））中的金属硫蛋白（MT）浓度的潜在用途，以绘制生物对金属污染的空间响应图。本研究应用分光光度法检测双壳类动物中的 MT，并首次检测到海绵中的 MT。结果表明，虽然贻贝和海绵组织及其周围环境（水和沉积物）中的一些金属浓度可能与金属污染的来源有关，但贻贝组织和海绵组织中的 MT 值则不然。贻贝和海绵中的 MT 与测试的任何金属（As、Cd、Cr、Cu、Pb、Hg、Ni、Ag、Sn、Zn）之间均未发现任何关系。此外，在污染严重的地区检测到的 MT 浓度最低，表明测试生物中的 MT 浓度并不完全与金属浓度相关，因为其他环境因素可能会影响该蛋白的诱导。这些生物可能对金属污染有很高的耐受性，长期暴露在高水平的污染下会导致多种解毒机制的发展。研究结果表明，在这种类型的生态系统中进一步研究金属胁迫可能需要检查其他指示物种和/或应用不同的生物监测技术。
