苯及其一取代化合物对底泥氨氧化活性联合抑制作用

Joint Inhibition of Benzene and Monosubstituted Benzenes on Ammonia-oxidizing Activity of Sediment

为研究复合苯系污染物对氮循环中硝化过程的影响 ,采用摇瓶实验研究了苯及其 3种一取代化合物 (苯酚、苯胺和硝基苯 )对底泥氨氧化活性的联合抑制作用 .结果表明 ,苯、苯胺、苯酚以及硝基苯进行两者及多者之间等毒性混合的 11组混合物 ,对底泥氨氧化活性的联合抑制作用中 ,有 7组表现为加和作用 ,3组表现为协同作用 ,只有苯和苯酚的混合物表现为拮抗作用 .含有硝基苯的混合物对底泥氨氧化活性的抑制作用一般表现为加和作用 .苯及其一取代化合物的混合物对底泥氨氧化活性半数抑制浓度 (IC50 ,μmol·L-1)与这种混合物中取代基的电负性ME有相关关系 :lgIC50 =2 197- 0 2 36ME ,随取代基电负性的增加 ,混合物对底泥氨氧化活性的联合抑制作用逐渐增强 .

The joint inhibitions of benzene and three kinds of monosubstituted benzenes (aniline, phenol and nitrobenzene) on ammonia-oxidizing activity of sediment was investigated in order to study the effects of combined pollutants on nitrification process in the nitrogen cycle. The results showed that the joint inhibiton of 11 different kinds of mixtures, including binary or multi-equitoxic mixtures among benzene, aniline, phenol and nitrobenzene, exhibited different effects on ammonia-oxidizing activity of sediment, among which seven were addictive effect, three were synergistic, and only the mixture of benzene and phenol was antagonism. A conclusion could be made that the addition of nitrobenze to a mixture usually exhibited addictive effect. There was a relationship between the half joint inhibition concentrations (IC 50, μmol·L -1) of benzene and monosubstittuted benzenes on ammonia-oxidizing activity of sediment and the mixed electronegativities(MEs): lgIC 50=2.197-0.236ME. With the increase of mixed electronegativities(MEs), the joint inhibitions of mixtures increased.