摘要
沉积物酸可挥发性硫能与二价重金属结合形成难溶硫化物,可以直接影响沉积物-水体系中重金属的生物有效性,近年来沉积物中酸可挥发性硫化物(AVS)与同步提取重金属(SEM)的生物有效性被广泛研究。总结了AVS沉积物样品保存方法、提取方法和AVS-SEM生物有效性评价方法发现:①大部分研究采用低温保存样品,储存时不充氮但加固定剂保存,采用聚乙烯样品袋保存的研究最多;②提取AVS时,大部分研究采用5 g样品量,用盐酸溶液提取,主要采用乙酸锌溶液吸收,提取温度多为室温,提取时间不一;③目前AVS-SEM生物有效性评价方法有(ΣSEM/AVS)比值法,(ΣSEM-AVS)差值法和(ΣSEM-AVS)/foc方法。采用(ΣSEM/AVS)比值法评价AVS-SEM生物有效性的研究较多;④沉积物硫化物测定的相关标准还不完善,建议进一步细化标准,明确规定样品的保存方法和测定时间,目前在用标准中沉积物硫化物的蒸馏吸收装置相对简单,建议加快研发新的蒸馏吸收仪器,同时利用新的仪器建立新的标准方法;⑤三种AVS-SEM生物有效性评价方法各有局限性,建议实际研究中采用多种方法相结合的综合评价方法。
Acid volatile sulfur in sediments can combine divalent heavy metals to form insoluble sulfide,which plays an important role in controlling the biological toxicity of heavy metals in sediment water system.Therefore,the biological toxicity of acid volatile sulfide(AVS)and simultaneous extraction of heavy metals(SEM)in sediments has been widely studied in recent years.This paper summarizes the preservation methods,extraction methods and AVS-SEM biological toxicity evaluation methods of AVS sediment samples.It is found that:①most studies use low-temperature preservation samples,which are not filled with nitrogen but stored with fixative,and the most studies are stored in polyethylene sample bags.②When extracting AVS,most studies use 5g sample volume and extract it with hydrochloric acid solution,which is mainly absorbed by zinc acetate solution.The extraction temperature is mostly room temperature and the extraction time is different.③At present,(ΣSEM/AVS)ratio method,(ΣSEM-AVS)difference method and(ΣSEM-AVS)/f OC method are used to evaluate the bioavailability of AVS-SEM.(ΣSEM/AVS)ratio method has been widely used to evaluate the bioavailability of AVS-SEM.④The relevant standards for the determination of sulfide in sediments are not perfect.It is suggested to further refine the standards and specify the preservation method and determination time of samples.At present,the distillation and absorption device of sediment sulfide in the standard are relatively simple.It is suggested to speed up the development of new distillation as well as absorption instruments and establish new standard methods by using new instruments.⑤The AVS-SEM bioavailability evaluation methods have their own limitations.It is suggested to adopt a comprehensive evaluation method combining multiple methods in practical research.
作者
罗龙娟
李桂娇
刘树函
Luo Longjuan;Li Guijiao;Liu Shuhan(Guangzhou Environmental Technology Center,Guangzhou,Guangdong 501235,China)
出处
《绿色科技》
2022年第12期161-165,共5页
Journal of Green Science and Technology
基金
生态环境保护能力建设与保障专项经费(编号:4001900000029)。