摘要
液晶单体(liquid crystal monomers,LCMs)是一类以二苯基或双环己烷作为骨干结构的有机化合物,广泛被应用于各类电子产品的液晶显示器中,其生产及使用量保持逐年增长,据推测,液晶显示器中使用的LCMs需求量已增加到约上千吨。研究表明LCMs具有持久性、生物蓄积性和生物毒性,是一种新型持久性有机污染物。由于液晶显示器中的LCMs没有与基材共价键合,因而在电子设备的生产、使用、处置和回收过程中,会不可避免地释放到环境中。本文主要以2018年以来发表的LCMs相关文献为基础,对其理化性质、生产和排放、在环境介质中的污染特征和环境行为以及人体健康风险评估进行了综述。现有研究结果表明,在沉积物、垃圾渗滤液、室内外灰尘、空气和生物样品如人体血液等介质中都检测到了LCMs的存在,其中大气和灰尘中赋存浓度最高。基于以上分析,本文提出LCMs的未来研究应该优先关注新型LCMs的识别和分析方法、在环境中的迁移转化行为及其在生物体内的蓄积代谢规律等。
Liquid crystal monomers(LCMs)are a class of synthetic organic chemicals with a diphenyl or bicyclohexane backbone with hydrogen atoms on the phenyl rings replaced with functional groups such as bromine,chlorine,cyano groups,or fluorine.LCMs have been used widely in liquid crystal displays(LCDs)in electrical and electronic products such as computers,mobile phones,and televisions.The rapidly developed LCD industry has also led to a continuous increase in the annual production volume for LCMs around the world.It has been estimated that demand for LCMs use in LCDs have rose to~1300 t by 2021.It has recently been suggested that LCMs should be considered to be emerging persistent organic pollutants of the environment because they may be persistent,bioaccumulative,and toxic.LCMs are not covalently bonded to any of the other materials used in LCDs,so can be unintentionally released into the environment during manufacturing,use,disposal,and recycling of LCD devices and pose serious risks to ecology and human health.Environmental and toxicological research on LCMs in the scientific community has just recently been initiated,and information is deficient in many fields.In this paper,information published since 2018 about LCMs physicochemical properties,production,and emissions;analytical methods for accurately quantifying LCMs;LCMs concentrations,behaviors,and fates in various environmental matrices;and the risks posed by LCMs to humans is reviewed.Recent studies have mainly focused on target LCMs concentrations and distributions,and most studies have involved gas chromatography mass spectrometry with target ions or ion pairs monitored.Many unknown LCMs may be overlooked using such methods because data for LCMs production volumes and use in commercial LCDs are limited.It has previously been found that E-waste dismantling caused large amounts of LCMs in waste LCD panels to be emitted in E-waste recycling areas.LCMs have been detected in sediment,soil,municipal landfill leachate,indoor and outdoor dust,air,and other environmental media.This indicates widespread LCMs contamination of the environment,particularly in E-waste processing areas.Most LCMs are semi-volatile organic compounds,so air is expected to be the main medium in which LCMs released from e-products are transported to other areas.These results also provide indirect evidence that humans are exposed to LCMs in environmental media through ingestion,dermal contact,and inhalation.To date,LCMs have been detected in human tissues in only four studies,and the systematic exploration of bio-monitoring regarding LCMs in the human matrices is still scant.Fluorinated LCMs have been found to be the dominant LCMs in both environmental media and biota,and exhibit higher persistent,bioaccumulative,or even toxic potential than other LCMs.Future studies should focus on developing methods combining target and non-target analysis for identifying and quantifying novel LCMs.It is suggested that large-scale field research should be performed to investigate LCMs migration and transport mechanisms from E-waste recycling areas to other environmental matrices.Studies on bioaccumulation characteristics of LCMs in biota should also be performed to allow the risks posed by LCMs to humans to be effectively assessed.
作者
杨倩玲
周婷婷
翁冀远
刘杨
刘寅
徐明
赵斌
高丽荣
郑明辉
Yang Qianling;Zhou Tingting;Weng Jiyuan;Liu Yang;Liu Yin;Xu Ming;Zhao Bin;Gao Lirong;Zheng Minghui(School of Environment,Hangzhou Institute for Advanced Study,University of Chinese Academy of Sciences,Hangzhou 310000,China;Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China)
出处
《生态毒理学报》
CAS
CSCD
北大核心
2023年第1期160-173,共14页
Asian Journal of Ecotoxicology
基金
国家自然科学基金资助项目(22276200)
中日友好环境保护中心重点实验室开放基金资助项目(ZXZRLJJ-202101)。
关键词
液晶单体
理化性质
污染特征
环境行为
人体暴露
liquid crystal monomers
physicochemical properties
pollution characteristics
environmental behaviors
human exposure
