氯/溴取代有机污染物在南瓜中的吸收、迁移和转化研究进展

Progress in the uptake,translocation,and transformation of chlorinated/brominated organic pollutants in pumpkin

氯/溴取代有机污染物具有持久性、毒性、蓄积性,对人类健康造成威胁,成为环境科学研究热点.以南瓜作为模型植物,通过土壤或水培培养及影响因素分析,探究氯/溴取代有机污染物在植物中的吸收、迁移和转化规律,对明晰其环境行为、生态风险评价等具有重要意义.本文在现有的研究基础上总结了模式植物的培养方案设置,氯/溴取代有机污染物在南瓜幼苗中的吸收途径、迁移形式、转化过程,分析了影响吸收和迁移速率的主要因素.氯/溴取代有机污染物的吸收途径包括:南瓜幼苗的根系从土壤或水中吸收有机污染物,南瓜幼苗的叶片从空气中吸收有机污染物;迁移形式包括:南瓜幼苗的根系吸收的有机污染物向上迁移至茎、叶,南瓜幼苗的叶片吸收的有机污染物向下迁移至茎、根;转化主要过程包括:脱卤反应、卤原子重排、裂解反应、羟基化反应、甲基化反应、去甲基化反应、糖基化反应、去糖基化反应.氯/溴取代有机污染物自身的物理化学性质是影响吸收和迁移速率的主要因素.本文对氯/溴取代有机污染物在南瓜中的环境行为进行总结,有助于明晰有机污染物在环境中的生物地球化学循环,为环境健康研究提供借鉴.

Chlorinated and brominated organic pollutants are persistent,toxic,and accumulative,which are threats to human health and has become a hot research topic in environmental science.The cultural methods and conditions in soil and hydroponics culture were investigated to study the uptake,translocation,and transformation of chlorinated and brominated organic pollutants in a model plant of pumpkin.These investigations are of great significance to clarify the environmental behavior and assess the ecological risks of chlorinated and brominated organic pollutants.Based on the present research,the cultural arrangements of model plants were summarized.The factors influencing the uptake,translocation,and transformation of chlorinated and brominated organic pollutants in pumpkin seedlings were analyzed.The uptake of chlorinated and brominated organic pollutants by pumpkin seedlings includes uptake by roots from soil or water,and uptake by leaves from air.The translocation of pollutants in pumpkin seedlings includes upward translocation of pollutants from roots to stem and leaves,and downward translocation of pollutants from leaves to stem and roots.The main transformation process includes dehalogenation,halogen atom rearrangement,cracking,hydroxylation,methylation,demethylation,glycation,and deglycation.The absorption and migration rates of chlorinated and brominated organic pollutants in pumpkin are mainly determined by their respective physical and chemical properties.This paper summarized the environmental behavior of chlorinated and brominated organic pollutants in pumpkin,which is helpful to clarify the biogeochemical cycle of organic pollutants and provide reference for environmental health research.