Effect of bisphenol A and pentachlorophenol on different enzymes of activated sludge

Abstract The relevant information on the impacts of emerging organic contaminants (EOCs) on the ecological environment, especially on the group of more vulnerable activated sludge is relatively less. In order to track biological activity of the aerobic sludge which is the most extended biological stage in the process of waste water treatment, the effects of bisphenol A (BPA) and pentachlorophenol (PCP) on urease, invertase and dehydrogenase were analyzed by spectrophotometry. It was found that the effects of BPA on urease and invertase mainly showed activation. The maximum relative impact rate on urease and invertase reached +91.7% and +182.3% respectively. The influence of BPA on dehydrogenase was observed to show visible inhibition. The maximum relative impact rate of BPA on dehydrogenase reached −89.9%. Effect of PCP on 3 kinds of enzyme were included activation (+) and inhibition (−) with different periods and concentration of exposure experiments. The maximum of the relative impact rates were +41.2% and −19.6% for urease, +84% and −76.8% for invertase, +18.0% and −54.8% for dehydrogenase respectively. Based on evaluating the sensitivity of physiological and biochemical indicators, and the accuracy of analytical methods as well, invertase activity could be recommended as a sensitive index for characterization of activated sludge. The obtained results could be used to analyze the potential impact of EOCs on ecological environment and even social and economic activities with significant information collected. It is helpful to serve as the basis for implementing relevant environmental regulatory and making decision, and for the relating enterprises to cope with adverse changes induced by community function under stress instantly.