重金属污染评估及其生物健康效应  

Risk assessments and health impacts of heavy metal pollution

作　　者：郑飞 郭欣[1] 郭博洋 黄贤亮 陈兵 ZHENG Fei;GUO Xin;GUO BoYang;HUANG XianLiang;CHEN Bing(School of Life Sciences,Hebei University,Baoding 071002,China)

机构地区：[1]河北大学生命科学学院,保定071002

出　　处：《中国科学：生命科学》2021年第9期1264-1273,共10页Scientia Sinica(Vitae)

基　　金：国家自然科学基金(批准号:31872304);河北省高校百名优秀创新人才支持计划(批准号:SLRC2019019);河北大学高层次人才支持计划(批准号:521000981358、521100221018)资助。

摘　　要：重金属污染是目前全球面临的最为严峻的环境问题之一,不仅引发了粮食安全危机,还直接危害着动物和人类健康.土壤线虫作为陆地环境中重金属污染的重要指示生物,不仅会对重金属的毒害产生复杂的防御机制,其肠道微生物还被证明可以协助宿主抵御重金属胁迫.本文系统梳理了国内外重金属的污染现状及其评估方法,以线虫为模型概述了重金属对土壤动物行为、生理、生化三个方面的影响,总结了动物对重金属暴露的应激响应,主要包括细胞壁和细胞膜的屏障作用、活性物质改变、金属硫蛋白表达以及非编码RNA调节等四个层面,提出了肠道微生物的组成和多样性作为指示重金属毒性的新方法,归纳了长期重金属暴露导致的生物适应性进化,包括重金属超积累基因、抗性基因、解毒基因的出现和富集等,进而量化环境胁迫引起的动物遗传变异在基因组水平上的响应,比如基因的抗性突变和抗性基因的协同作用.最后,本文对重金属生态毒理学的研究进行了展望,指出未来研究需着眼于当下的生态环境和人类健康,探索土壤动物肠道微生物的生态作用,深入探究重金属毒性发生发展以及生物解毒的潜在机制.Heavy metal pollution is a serious global environmental issue,posing huge risks to food security and human health.As a typical biomarker of heavy metals,soil nematodes develop complex defenses in response to heavy metal exposures.Meanwhile,their gut microbiomes assist host resistance to heavy metals.Here we review the pollution status and assessment methods of heavy metals at home and abroad and summarize their effects on the behavior,physiology,and biochemistry of soil nematodes.Additionally,defense mechanisms of organisms against heavy metals are reviewed,including barrier functions of the cell wall and membrane,changes in active substances,metallothionein overexpression,and noncoding RNA regulation.We propose that the diversity and composition of the nematode gut microbiome can be used as a new indicator of heavy metal toxicity.Furthermore,long-term heavy metal exposure could lead to adaptive evolution,such as the emergence and enrichment of heavy metal hyperaccumulation,resistance,and detoxification genes.Additionally,we can map genetic changes,such as resistance mutations in genes and synergies of resistance,by quantifying the genome-level response of genetic variation under environmental stresses.Finally,we provide a prospect on the ecotoxicology of heavy metals and indicate that future research should focus on the current ecological environment and human health,explore the ecological role of soil fauna gut microbiome,and further understand the potential mechanism of occurrence and development of heavy metal toxicity and biological detoxification.

关 键 词：重金属 生物毒性 解毒机制 线虫 肠道微生物 适应性进化 

分 类 号：X820[环境科学与工程—环境工程]