摘要
酚类化学品是自然界中一类典型的外源性有毒物质,此类化学品对活性污泥的毒性数据对评价它们在环境中的风险至关重要。该文采用ISO标准方法测定了4种酚类化学品对硝化活性污泥的抑制效应。结果表明,3,5-二氯苯酚、2,4-二氯酚、4-硝基苯酚以及2-苯基苯酚对污泥硝化作用均能产生毒性,它们的EC（50）值依次为1.02、1.31、5.23、33.2 mg/L,95%置信限依次为0.9-1.2、0.69-2.45、4.96-6.17、27.7-39.8 mg/L。4种酚类化学品对硝化污泥的抑制类型属竞争性抑制,毒性作用机制在于酚类化学品抢夺了氨氧化细菌对AMO的活性位点,从而阻碍了NH3向羟胺的转化,进一步导致硝化难以完成。
Phenolic chemicals are typical xenobiotic toxic substances in nature. The toxicity data of those compounds on activated sludge is of vital importance to risk assessment in the environment. Inhibition effect of four phenolic chemicals on nitrifying activated sludge was tested by employing ISO standard method in this study. The experimental results showed that2,4-dichlorophenol, 4-nitrophenol and 2-phenyl-phenol had a toxicity on the nitrifying bacteria from activated sludge, with 3h-EC（50） values as 1.02, 1.31, 5.23 and 33.2 mg/L, and the 95% confidence limit as 0.9-1.2 mg/L, 0.69-2.45 mg/L, 4.96-6.17mg/L and 27.7 -39.8 mg/L respectively. The type of inhibition for phenolic compounds to nitrification bacteria was competitive inhibition, the mechanism was that phenolic compounds snatch ammonia oxidizing bacteria to AMO active site,preventing the conversion of NH3 to hydroxylamine, and further lead to nitrification unable to complete
出处
《环境科学与技术》
CAS
CSCD
北大核心
2016年第10期14-19,共6页
Environmental Science & Technology
基金
国家高技术研究发展计划(863)项目(2013AA060A308)
公益性行业(环保)科研专项基金(201309028)
关键词
酚类化学品
硝化污泥
抑制
EC50
phenolic chemicals
nitrifying sludge
inhibition
EC50
