细颗粒物(PM_(2.5))主要组分模拟溶液对发光细菌的光抑制分析

为明确NH_4~+、 NO_3~-、SO_4~(2-)及金属等组分在水溶性提取液对发光细菌的光抑制过程中所起的作用,参照PM_(2.5)样品提取液浓度,模拟配制与3级以上PM_(2.5)样品提取液中主要组分:硫酸盐、硝酸盐、氨盐相同浓度的溶液,同时选取与PM_(2.5)可溶性提取液发光抑制率相关性较强的铅、锌,配制不同浓度级别模拟溶液,测试各单一组分对发光细菌的发光抑制率及其混合溶液对发光细菌的联合影响效应。基于毒性单位法(TU)、相加指数法(AI)和混合毒性指数法(MTI)评价了混合体系联合影响的作用类型。结果表明,与3~6级PM_(2.5)可溶性提取液中硫酸氨、硫酸氢氨、硝酸氨、硫酸锌和硝酸铅浓度相同的模拟溶液对发光细菌的发光没有抑制作用。不同的评价方法对PM_(2.5)主要组分混合体系联合效应评价结果具有较好的一致性,硫酸氨、硝酸氨、硫酸氢氨混合溶液中,对发光细菌的光抑制均为硫酸氢氨的独立作用,硫酸锌与硝酸铅的混合体系,锌和铅对发光细菌的联合影响效应表现为协同,硫酸氨、硝酸氨、硫酸氢氨与硫酸锌、硝酸铅的多元混合体系呈现协同作用。

Luminescent Inhibition Test of Luminous Bacteria with the Simulated Solution of Main Components of PM2.5

Based on the concentrations of the main components of sulfate, nitrate ammonium salts in water-soluble extraction solution from PM_2.5 samples above third grade pollution level, the simulated solutions with different concentrations of NH₄⁺, NO₃^-, SO₄^2-, Zn²⁺ and Pb²⁺ were respectively made to study the effects from these ions on the inhibition rate of the luminous bacteria. The individual and joint effects on the inhibition rate of the luminous bacteria were respectively analyzed with the simulated solutions with single component and mixed components of such ions as NH₄⁺, NO₃^-, SO₄^2-, Zn²⁺ and Pb²⁺. The characteristics of the joint effects were evaluated by toxicity unit (TU), additive index (AI) and mixtures toxicity index (MTI). The Results showed that the simulated solutions with the same concentrations of ammonia sulfate, ammonium hydrogen sulfate, ammonium nitrate, zinc sulfate and lead nitrate as those in the water-soluble extraction solution from PM_2.5 samples at pollution levels ranging from 3 to 6 did not inhibit the luminescence of Vibrio fischeri. The results of the three methods for evaluating the joint effects were in agreement, and showed that the ammonium hydrogen sulfate affected independently the inhibition rate of luminous bacteria in the mixing of ammonium sulfate, ammonium hydrogen sulfate, and ammonia nitric. Moreover, the synergistic effects on the inhibition existed in the multi-mixture systems of the simulated solution mixed by ammonium sulfate, ammonium hydrogen sulfate, ammonia nitric and lead, zinc salt.