传统的废水处理厂(WWTP)不是为减少抗生素而设计的,它们的流出物是这些新兴污染物进入水生环境的主要途径之一,由于它们的毒性而引起重大关注,持久性,和生物蓄积性。当含有抗生素的废水进入生物反应器时,它们可以影响活性污泥的微生物群落,影响有机物和养分的生物降解过程。关于在抗生素存在下活性炭对生物反应器内活性污泥的影响的信息很少。鉴于此,代表性抗生素的效果,环丙沙星(CIP),萘啶酸(NAL),和红霉素(ERY),通过有和没有活性炭的呼吸测量法分析了污水处理厂常规活性污泥的性能。NAL和ERY对净异养生物量增长率(r\'x,H),减少百分比为26%-90%和31%-81%,分别。活性炭的加入减轻了这种影响,尤其是对于ERY来说,在r\'x中增量甚至为8%,当使用5ppm的ERY和80ppm的活性炭时,混合过程的H与不存在抗生素和活性炭时的值相比。这种效果归因于ERY的保留增强,与NAL相比,在活性炭的表面,可能是由于其较高的分子大小和对活性炭的亲和力(logKow=3.06)。在低污泥保留时间(低于8天)时,这种影响更为明显。实践要点:环丙沙星(CIP),萘啶酸(NAL),和红霉素(ERY)进行了研究。NAL和ERY对异养生长速率产生负面影响。研究了在活性炭存在下抗生素对微生物的影响。活性炭由于其吸附保留而与ERY主要相关。在低污泥保留时间下,活性炭的增强作用更为显着。
Conventional wastewater treatment plants (WWTPs) are not designed for the abatement of antibiotics, and their effluents are one of the main entry ways of these emerging contaminants to the aquatic environment, causing major concern due to their toxicity, persistence, and bioaccumulation. When wastewater containing antibiotics enters the bioreactor, they can impact microbial communities of the activated sludge, affecting biodegradation processes of organic matter and nutrients. There is scarce information about the effect of activated carbon on the activated sludge within the bioreactor in presence of antibiotics. In light of this, the effect of representative antibiotics, ciprofloxacin (CIP), nalidixic acid (NAL), and erythromycin (ERY), on the performance of a conventional activated sludge of a WWTP was analyzed by respirometry with and without activated carbon. NAL and ERY negatively affected the net heterotrophic biomass growth rate (r\'x,H), with reduction percentages of 26%-90% and 31%-81%, respectively. The addition of activated carbon mitigated this effect, especially for ERY, with increments of even 8% in the r\'x,H for the hybrid process when working with 5 ppm of ERY and 80 ppm of activated carbon compared with the value in the absence of antibiotic and activated carbon. This effect was attributed to the enhanced retention of ERY, in comparison to NAL, on the surface of the activated carbon, probably due to its higher molecular size and affinity towards the activated carbon (log Kow = 3.06). This effect was more marked at low sludge retention times (below 8 days). PRACTITIONER POINTS: Ciprofloxacin (CIP), nalidixic acid (NAL), and erythromycin (ERY) were studied. NAL and ERY exerted negative impact on heterotrophic growth rate. Effect of antibiotics on microorganisms in the presence of activated carbon was studied. Activated carbon was mainly relevant for ERY due to its adsorption retention. Enhancement by activated carbon was more significant at low sludge retention times.