应用生物配体模型评价海洋沉积物重金属毒性的研究进展

海洋沉积物中金属毒性的判定一直是较为复杂的科学问题。近年来较多的研究表明,沉积物中金属的毒性和生物可利用性与其总含量无关,而与其存在形态密切相关。沉积物生物配体模型(s-BLM)是建立在较新的科研成果上用以判断沉积物中金属毒性的一个综合模型。s-BLM主要应用于有氧环境下,在测定活性金属、硫化物、有机碳的基础上,结合间隙水中的化学成分来计算多种金属的毒性阈值。s-BLM与以往应用于厌氧环境下的酸可挥发性硫化物/同步萃取金属(AVS/SEM)模型形成互补,从而能够全面系统的判断沉积物中的多种重金属(Cu、Pb、Zn、Ni、Cd、Ag)的生物毒性。本文全面介绍了s-BLM的由来和构建,重点探讨了其应用、研究进展及局限性。目前,该模型在国际上已受到广泛关注和应用,但我国在该方面的研究尚属空白。类似模型的研究和发展对于更科学的制定沉积物环境质量标准有重要意义。

Research progress on assessment of heavy metal toxicity in marine sediment by biotic ligand model

The assessment of the metal toxicity in sediment always is a complicated topic to tackle.In recent years,many researches showed that the bioavailability and toxicity of metals in sediments were not related with the total metal concentrations,but the metal speciation in sediments.Based on the recent research results,the sediment biotic ligand model(s-BLM) was established to assess the metal toxicity in sediments.The s-BLM is applied in oxic environments,based on the concentrations of the labile metals,acid volatile sulfide and organic carbon,along with the information on pore-water chemistry,to calculate the toxicity threshold of the metals.Combined with the AVS/SED model that is used for assessing the metal toxicity in anoxic sediment environment,the s-BLM can be used to assess comprehensively the toxicity of several metals(Cu,Pb,Zn,Ni,Cd,Ag) in sediments.This article present the origin and structure of the s-BLM,focused on its application,current research status and limitations.Currently,and the s-BLM has drawn many attentions and applications internationally,while in China,the study and application of it is still vacant.The study and development of the models should have the great value for establishing the better sediment quality criteria.