Zhang Jin, Ding Ting-Ting, Dong Xin-Qin, Bian Zhi-Qiang
Key Laboratory of Water Pollution Control and Wastewater Resource of Anhui Province, College of Environment and Energy Engineering, Anhui Jianzhu University Hefei 230601 PR China
Beijing Key Laboratory for Emerging Organic Contaminants Control, Tsinghua University Beijing 100084 PR China.
RSC Adv. 2018 Jul 20;8(46):26089-26098. doi: 10.1039/c8ra04191a. eCollection 2018 Jul 19.
Toxicity interaction has aroused many researchers' interest in the combined toxicity of pollutants. Recently, some published studies have shown that the toxicity of some mixture pollutants is time dependent and well correlated with certain components in the mixture. Therefore, to investigate whether toxicity interaction is affected by the exposure time or certain components, synergism and antagonism within typical environmental contaminants of heavy metal mixtures were analyzed in different exposure times. Herein, three binary and one ternary mixture systems were designed by using three heavy metals: cadmium chloride, lead chloride (Pb) and manganese(ii) chloride tetrahydrate (Mn). For each mixture system, five mixture rays with different concentration ratios were arranged by direct equipartition ray design and uniform design ray methods. The toxicities of the three heavy metals and 20 mixture rays towards photobacteria sp.-Q67 (Q67) were determined by the established time-dependent microplate toxicity analysis (t-MTA) in different exposure durations of 0.25, 2, 4, 8 and 12 h. It was shown that the toxicities of three heavy metals (Cd, Pb and Mn) as well as their binary and ternary mixture rays to Q67 were also time dependent, but different metals or mixture rays showed different time characteristics. Surprisingly, some mixture rays exhibited antagonism or synergism with time dependency and the time characteristics varied in different mixture systems. Furthermore, the binary or ternary mixture systems with Pb displayed antagonism, while the Cd-Mn mixture system without Pb exhibited additive action or synergism, which indicated that Pb was probably the causative agent of antagonism produced by mixtures.
毒性相互作用引发了许多研究人员对污染物联合毒性的兴趣。最近，一些已发表的研究表明，某些混合污染物的毒性具有时间依赖性，并且与混合物中的某些成分密切相关。因此，为了研究毒性相互作用是否受暴露时间或某些成分的影响，分析了不同暴露时间下重金属混合物典型环境污染物中的协同作用和拮抗作用。在此，使用三种重金属：氯化镉、氯化铅（Pb）和四水合氯化锰（Mn）设计了三个二元和一个三元混合体系。对于每个混合体系，通过直接等份射线设计和均匀设计射线方法安排了五个不同浓度比的混合射线。通过建立的时间依赖性微孔板毒性分析（t-MTA）在0.25、2、4、8和12小时的不同暴露持续时间下，测定了三种重金属和20种混合射线对发光菌sp.-Q67（Q67）的毒性。结果表明，三种重金属（Cd、Pb和Mn）及其二元和三元混合射线对Q67的毒性也具有时间依赖性，但不同的金属或混合射线表现出不同的时间特征。令人惊讶的是，一些混合射线表现出具有时间依赖性的拮抗作用或协同作用，并且时间特征在不同的混合体系中有所不同。此外，含Pb的二元或三元混合体系表现出拮抗作用，而不含Pb的Cd-Mn混合体系表现出相加作用或协同作用，这表明Pb可能是混合物产生拮抗作用的原因。
