Removal of Two Pharmaceutically Active Compounds from Aqueous Phase Using an Engineered Floodplain Filtration System

This study investigated the removal of two model pharmaceutically active compounds (PhAcs), viz., ibuprofen and triclosan, in lab‐scale engineered floodplain filtration (EFF) system. Biodegradation experiments were performed to acquire knowledge about the degradation of the targeted PhAcs, at an initial concentration of 350 µg/L. Biodegradation results showed that the two compounds were bio‐transformed to >70% after 15 days of incubation. Column tests were performed in a statistically significant manner to determine the adsorptive potential of the suggested filler layer in the EFF (C/C₀), by varying the flow rate and initial concentration of the compound. It was observed based on the F and p‐values that the main effects (F = 3163, p < 0.005) were more significant than the interactive effects (F = 9561, p < 0.05) for both ibuprofen and triclosan removal. Besides, by performing the Student's “t” test, it was concluded that the flow rate plays a major role in determining the rapidness of achieving complete breakthrough than the initial concentration of both the compounds. The data obtained from column studies under biotic conditions indicated that the removal mechanism for PhAcs is mainly biotransformation based, and that an EFF system may be effectively used to remove these emerging compounds during ground water recharge for water recycling.     

Production of Drinking Water from Highly Contaminated Surface Waters: Removal of Organic,Inorganic, and Microbial Contaminants Applying Mobile Membrane Filtration Units

In military out of area missions of the Bundeswehr, it can be necessary to produce drinking water even from highly polluted surface waters containing a variety of organic, inorganic, and microbiological contaminants. Thus, mobile drinking water purification systems must be able to remove such contaminants as far as possible to meet the requirements of the German and European drinking water regulation/directive. Presently, two novel drinking water purification units applying membrane filtration undergo intensive long‐term trials carried out by the Bundeswehr. If these trials positively proof the functionality of these units and their ability to remove all possible contaminants they shall substitute so far available devices which use large amounts of chemicals and charcoal filtration for water purification.In the course of a research project, the functionality of the new devices and their efficacy to remove high amounts of algae, microbes, and organic and inorganic pollutants are additionally tested in “worst‐case” field studies. In September 2000, the first mobile drinking water purification unit was tested at the Teltowkanal in Berlin, Germany.This canal was chosen because it carries high burdens of municipal sewage effluents. The results from the fatigue test confirmed the ability of the water purification unit to reduce the concentrations of all contaminants meeting the maximum tolerance levels set by the German/European drinking water regulation.The pre‐filtration device was very effective in removing algae and solid particles to protect the membranes from clogging and to enable an almost maintenance‐free operation. Residues of pharmaceuticals and some other organic contaminants have almost totally been removed from the surface water where they were detected at individual concentrations up to the μg/L‐level.     

Verhalten ausgewählter Arzneimittel bei der künstlichen Grundwasseranreicherung – Eliminierung und Effekte auf die mikrobielle Besiedlung

Behaviour of Some Pharmaceuticals during Artificial Groundwater Recharge – Elimination and Effects on Microbiology The behaviour of bezafibrate, carbamazepine, clofibric acid, diclofenac, ibuprofen, and gemfibrozil during artificial groundwater recharge was investigated with different test systems simulating field conditions. The given concentrations of the pharmaceuticals were 100 μg/L in the influent of the systems. Concentrations in the influent as well as in the effluent were measured by GC‐MS. These column experiments indicated a significant elimination of bezafibrate, diclofenac, and ibuprofen (60 to 80%) during slow sand filtration. The results showed a moderate elimination of clofibric acid and gemfibrozil (40 to 60%) but a rather low elimination of carbamazepine (<40%). The adaptation times until the elimination processes started were about 5 days. Only the elimination of carbamazepine needed a lag phase up to 17 days. Additional column experiments with groundwater model systems indicated a high persistence of pharmaceuticals under aerobic and anaerobic groundwater conditions. The elimination was less than 20%. Only diclofenac was eliminated with rates between 60% and 80% in aerobic systems and between 40% and 60% in anaerobic systems. Analysis of eubacterial 16S‐rDNA by PCR and DGGE demonstrated changes in the microbial community structure in slow sand filters after application of pharmaceuticals. Adaptation processes may cause these changes, e.g. the appearance or disappearance of single species. Also differences between the populations of water and of the solid phase in slow sand filters could be demonstrated by DGGE pattern.     

Occurrence and Distribution of Organic Contaminants in the Aquatic System in Berlin. Part I: Drug Residues and other Polar Contaminants in Berlin Surface and Groundwater

Several polar contaminants were found in screening analyses of 30 representative surface water samples collected from rivers, lakes, and canals in Berlin. Residues of pharmaceuticals and N-(phenylsulfonyl)-sarcosine originating from various sewage treatment plants effluents were found at concentrations up to the μg/L-level in the surface water, whereas the concentrations of polar pesticides such as dichlorprop and mecoprop were always below 0.1 μg/L. The pharmaceuticals most frequently detected in the surface water samples include clofibric acid, diclofenac, ibuprofen, propiphenazone, and two other drug metabolites. Additional investigations of groundwater wells of a drinking water plant have shown that polar contaminants such as drug residues or N-(phenylsulfonyl)-sarcosine easily leach through the subsoil into the groundwater aquifers when contaminated surface water is used for groundwater recharge in drinking water production.     

Can pharmaceuticals interfere with the synthesis of active androgens in male fish? An in vitro study

The in vitro interference of fibrate (gemfibrozil, clofibrate, clofibric acid), anti-inflammatory (ibuprofen, diclofenac), and anti-depressive (fluoxetine, fluvoxamine) drugs with key enzymatic activities—C17,20-lyase and CYP11β-involved in the synthesis of active androgens in gonads of male carp have been investigated. Among the tested compounds, fluvoxamine and fluoxetine were the strongest inhibitors of C17,20-lyase and CYP11β enzymes, with IC50s in the range of 321-335 μM and 244-550 μM, respectively. To our knowledge this is the first report on the interaction of pharmaceutical compounds with enzymatic systems involved in the synthesis of oxy-androgens. As oxy-androgens are known to influence spermatogenesis and stimulate reproductive behavior and secondary sexual characteristics in male fish, this work highlights the need for further investigating these endpoints when designing specific in vivo studies to assess the endocrine disruptive effect of pharmaceuticals in fish.     

Micropollutants in four Brazilian water reservoirs

The concern about emerging contaminants such as pharmaceuticals is growing, mainly due to the increased global consumption of synthetic chemicals and the potential risk to environmental and human health. Although developing countries may be hotspots of pharmaceutical pollution, the knowledge about the occurrence of pharmaceuticals is still limited and patchy. Brazil holds one of the largest freshwater volumes globally, yet, little is known about the occurrence of pharmaceuticals in reservoirs although they make up key water sources. The aim of this study was, therefore, to investigate micropollutant occurrence, mainly pharmaceuticals, in four freshwater reservoirs distributed in Brazil. Water samples were collected in the Curuá-Una (CUN, Amazon region), Chapéu D’Uvas (CDU, Atlantic Forest region), Funil (FUN, Atlantic Forest region), and Simplício (SIM, Atlantic Forest region) reservoirs. The occurrence of 28 different micropollutants, including 26 pharmaceuticals, was investigated with target analysis on a UHPLC-Orbitrap-MS/MS, and a non-target screening approach was performed on all water samples to identify the presence of additional contaminants. The highest micropollutant concentrations were observed in FUN and SIM, which are the reservoirs with the largest population size in the catchment. Only caffeine was detected in CDU and CUN, which are reservoirs less influenced by urbanization. Metformin was the pharmaceutical with the highest concentrations, reaching 2 191 ng L⁻¹ in FUN. The non-target screening identified 125 chemicals, of which most were pharmaceuticals. The numbers of compounds identified and which were above the LOQ were higher in FUN and SIM, in agreement with results from the target analysis. Metformin is the compound with the highest risk to affect FUN reservoir negatively, based on calculated risk quotients. Considering that the reservoirs are used for multiple purposes, including water supply, irrigation, and aquaculture, it is important to continue investigating micropollutant occurrence to guarantee environmental and human health.