No abstract

The removal efficiency of pharmaceuticals in wastewater treatment plants (WWTPs) is variable and some of these compounds pass these plants almost intact and others presenting a removal efficiency close to 100%. Their incomplete removal results in a continuous discharge of pharmaceuticals into the environment. To assess the profile of contamination of influents and effluents over a day, a set of 83 pharmaceuticals were evaluated hourly in a WWTP in Leiria, Portugal. The composite samples of the influent and effluent were also collected. Concentrations varied from 1 in WWTP influents, and carbamazepine, fluoxetine, sertraline the pharmaceuticals with an RQ > 1 in WWTP effluents.

No abstract

Several pesticides and pharmaceuticals (PP) have been detected in the effluent of a full-scale Portuguese Wastewater Treatment Plant (WWTP). Their presence contributed to the environmental burdens associated with the existing treatment of the Municipal Wastewater (MWW) in the impact categories of Human Carcinogenicity, Non-Carcinogenicity, and Freshwater toxicities on average by 85%, 60%, and 90%, respectively (ReciPe2016 and USEtox methods). The environmental and economic assessment of the installation of an Anodic Oxidation (AO) unit for PPs’ removal was performed through Life Cycle and Economic Analysis, considering two types of anodes, the Boron-Doped Diamond (BDD) and the Mixed Metal Oxides (MMO). The operation of the AO unit increased the environmental burdens of the system by 95% on average (USEtox), but these impacts can be partially compensated by the avoided the production of non-renewable energy in the Portuguese electricity mix by biogas cogeneration at the WWTP. If the construction of the AO unit and the manufacturing of the electrodes are considered, the Human and Freshwater Toxicities are often higher than the environmental benefits derived from the PPs’ removal. On the economic side, the MMO configuration is clearly more advantageous, whereas BDD is environmentally more favorable. The issue of the presence of PP in MWW effluents has to be addressed as an integrated solution both improving upstream PP’s management and adopting PP’s removal technologies strongly supported by renewable energies. Further insights are needed for the assessment of fate and of the environmental effects of PP in the sludge.

Investigation during 11-month period was performed to study the presence of caffeine in the Lis River in Leiria Town in Portugal, and a monitoring during 9-month period was realized to check the contribution of the human pollution of two wastewater treatment plants (WWTPs) that discharge their effluents to the studied river. The samples were collected in five sampling points along the river and in two influents and two effluents of the studied WWTPs. Caffeine was detected in all ninety-one collected samples. The caffeine concentration ranged from 25.3 to 321 ng/L in the river samples, from 112 to 1927 ng/L in the WWTP effluents, and from 9478 to 83,901 ng/L in the WWTP influents. The highest concentration in the river was detected in the two sampling points located after the effluent discharge points and reached 315 and 321 ng/L. Risk assessment was performed for three trophic levels using the risk quotient calculation and revealed that caffeine do not cause toxic effect on Daphnia magna and on fish but could be possibly toxic to algae. The results proved that caffeine can be an effective indicator of human-born pollution.