不同因子对土霉素与汞络合反应中溶解性气态汞的影响

Effects of different factors on dissolved gaseous mercury in the complexation reaction of antibiotics with mercury

【目的】研究不同环境因子下土霉素(OTC)与汞(Hg)络合后溶解性气态汞(DGM)的变化特征,可了解抗生素与汞的复合污染问题。【方法】利用实验室模拟实验,以OTC(1μmol·L^−1)和氯化汞(HgCl21μmol·L^−1)溶液为材料,以pH、光照、盐度和氧化还原为不同影响条件,探究反应后DGM的变化特征。【结果】不同环境因子对水体DGM的影响起主要作用,DGM随pH的增加呈减少趋势,酸性条件下的DGM显著高于碱性条件。光照条件下DGM略高于黑暗条件。淡水条件中的DGM显著高于海水条件。厌氧条件下的DGM在试验初期低于好氧条件,在第10天之后高于好氧条件。【结论】OTC与汞会发生络合反应,且络合反应有利于DGM的形成。不同环境因子也会影响两者络合后产生的DGM。OTC与Hg络合后反应生成的DGM要高于对照组,但OTC的影响程度低于本身环境因子的影响。

[Objective]To better understand the combined pollution of antibiotics and mercury,an investigation is conducted of the influence of different environmental factors on the dissolved gases mercury(DGM)formed in the liquid phase after the complexion reaction of oxytetracycline(OTC)with mercury.[Method]With OTC solution(1μmol·L^−1)and mercury chloride(HgCl21μmol·L^−1)selected as materials,simulation experiments were conducted in the laboratory with pH,light,salinity,and redox employed as the environmental factors to explore the changing characteristics of DGM concentration after the reaction.[Result]Environmental factors have significant impact on the formation of DGM.There is a significant decrease in DGM concentration with the increase of pH.The DGM concentration in the condition of light irradiation was slightly higher than that in the dark condition.The DGM concentration in sea water was significantly higher than that in freshwater.The DGM concentration in anaerobic condition was slightly lower than that in aerobic condition but the situation was reversed after ten days.[Conclusion]The complexation reaction of OTC with mercury occurs and is beneficial to the formation of DGM which is subject to the impact of different environmental factors.The DGM formed by the reaction of OTC and Hg is higher than that in the control group.However,the influence of OTC on the formation of DGM is not as strong as the environmental factors.