Status of hormones and painkillers in wastewater effluents across several European states-considerations for the EU watch list concerning estradiols and diclofenac

Present technologies for wastewater treatment do not sufficiently address the increasing pollution situation of receiving water bodies, especially with the growing use of personal care products and pharmaceuticals (PPCP) in the private household and health sector. The relevance of addressing this problem of organic pollutants was taken into account by the Directive 2013/39/EU that introduced (i) the quality evaluation of aquatic compartments, (ii) the polluter pays principle, (iii) the need for innovative and affordable wastewater treatment technologies, and (iv) the identification of pollution causes including a list of principal compounds to be monitored. In addition, a watch list of 10 other substances was recently defined by Decision 2015/495 on March 20, 2015. This list contains, among several recalcitrant chemicals, the painkiller diclofenac and the hormones 17β-estradiol and 17α-ethinylestradiol. Although some modern approaches for their removal exist, such as advanced oxidation processes (AOPs), retrofitting most wastewater treatment plants with AOPs will not be acceptable as consistent investment at reasonable operational cost. Additionally, by-product and transformation product formation has to be considered. The same is true for membrane-based technologies (nanofiltration, reversed osmosis) despite of the incredible progress that has been made during recent years, because these systems lead to higher operation costs (mainly due to higher energy consumption) so that the majority of communities will not easily accept them. Advanced technologies in wastewater treatment like membrane bioreactors (MBR) that integrate biological degradation of organic matter with membrane filtration have proven a more complete elimination of emerging pollutants in a rather cost- and labor-intensive technology. Still, most of the presently applied methods are incapable of removing critical compounds completely. In this opinion paper, the state of the art of European WWTPs is reflected, and capacities of single methods are described. Furthermore, the need for analytical standards, risk assessment, and economic planning is stressed. The survey results in the conclusion that combinations of different conventional and advanced technologies including biological and plant-based strategies seem to be most promising to solve the burning problem of polluting our environment with hazardous emerging xenobiotics.

Comparison of two different anaerobic feeding strategies to establish a stable aerobic granulated sludge bed

Two different anaerobic feeding strategies were compared to optimize the development and performance of aerobic granules. A stable aerobic granulation of activated sludge was achieved with an anaerobic plug flow operation (PI) and a fast influent step followed by an anaerobic mixing phase (PII). Two lab scale sequencing batch reactors (SBRs) were operated to test the different operation modes. PI with plug flow and a reactor H/D (height/diameter) ratio of 9 achieved a biomass concentration of 20 g(TSS)/L and an effluent TSS concentration of 0.10 g(TSS)/L. PII with the mixed anaerobic phase directly after feeding and a reactor H/D ratio of 2 achieved a biomass concentration of 9 g(TSS)/L and an effluent quality of 0.05 g(TSS)/L. Furthermore, it is shown that the plug flow regime during anaerobic feeding together with the lower H/D ratio of 2 led to channeling effects, which resulted in lower storage of organic carbon and a general destabilization of the granulation process. Compared to the plug flow regime (PI), the anaerobic mixing (PII) provided lower substrate gradients within the biofilm. However, these disadvantages could be compensated by higher mass transfer coefficients in PII (k(L) = 0.3 m/d for PI; k(L) = 86 m/d for PII) during the anaerobic phase.

Pilot-scale anaerobic submerged membrane bioreactor (AnSMBR) treating municipal wastewater: the fouling phenomenon and long-term operation

An anaerobic submerged membrane bioreactor (AnSMBR) on pilot-scale treating a mixture composed of municipal wastewater and glucose under mesophilic temperature conditions was operated for 206 days. The performance of the AnSMBR was evaluated at different fluxes, biomass concentrations and gas sparging velocities (GSV). GSV was used to control fouling. In addition, the AnSMBR was operated in cycles that included relaxation and backwashing phases. The increase in the transmembrane pressure (fouling rate) was measured under different operational conditions and was used to evaluate the stability of the process. The fouling rate could be controlled for a long period of time at a flux of 7 l m(-2) h(-1) with a GSV of 62 m/h and an average biomass concentration of 14.8 g TSS/L. The membrane was physically cleaned after 156 days of operation. The cleaning efficiency was almost 100% indicating that no irreversible fouling was developed inside the pores of the membrane. The COD removal efficiency was close to 90%. As in anaerobic processes, nutrients were not exposed to degradation and almost no pathogens were found in the effluent, hence the effluent could be used for irrigation in agriculture.

Infiltration of a copper roof runoff through artificial barriers

On-site infiltration of a copper roof runoff may contribute to deterioration of the ground and ground water. To avoid such a negative effect the performance of two different technical systems, equipped with four different barrier materials, regarding copper elimination was examined in a field study. During the period March 2004 to January 2005, 16 rain events were examined. Copper concentrations between 200 and 11,000 microg/L in the roof runoff during a rain event were observed. The cover material of the roof and the drainage system were responsible for the high concentrations of copper in the roof runoff. It was evident that roof aspects facing towards the wind direction were receiving higher rainfall, thus were establishing higher copper runoff rates. The retention facilities have reached a performance of up to 97% regarding copper elimination.

The anaesthesia critical incident reporting system: an experience based database

To date there have been fewer than a dozen studies on the nature of, and contributory factors in, critical incidents (CI) in anaesthesia. The first of these, by Cooper and colleagues, showed that the vast majority of their CI involved human error [1]. Most recently, the on-going Australian Incident Monitoring Study (AIMS), with now more than 2000 reports, has shows that aspects of 'system failure' may constitute the bulk of the contributory factors, even though some human error may be detected in about 80% of the analysed cases [2]. We set up a Critical Incident Reporting System (CIRS) to collect anonymous CI in anaesthesia using a reporting form on the Internet. CIRS analysis of the first 60 cases corroborates the findings of previous CI studies. In addition, our preliminary results have shown certain important trends, especially those concerning the contributory factor of communication in the Operating Theatre. Although to date we are unable to assess the educational importance of these CI reports, we believe that there is great potential for this aspect of CIRS.