Abteilung Umweltchemie

Synthetic water-soluble polymeric materials are widely employed in e.g. cleaning detergents, personal care products, paints or textiles. Accordingly, these compounds reach sewage treatment plants and may enter receiving waters and the aquatic environment. Characteristically, these molecules show a polydisperse molecular weight distribution, comprising multiple repeating units, i.e. a homologous series (HS). Their analysis in environmentally relevant samples has received some attention over the last two decades, however, the majority of previous studies focused on surfactants and a molecular weight range <1000 Da. To capture a wider range on the mass versus polarity plane and extend towards less polar contaminants, a workflow was established using three different ionization strategies, namely conventional electrospray ionization, atmospheric pressure photoionization and atmospheric pressure chemical ionization. The data evaluation consisted of suspect screening of ca. 1200 suspect entries and a non-target screening of HS with pre-defined accurate mass differences using ca. 400 molecular formulas of repeating units of HS as input and repeating retention time shifts as HS indicator.
To study the fate of these water-soluble polymeric substances in the wastewater treatment process, the different stages, i.e. after primary and secondary clarifier, and after ozonation followed by sand filtration, were sampled at a Swiss wastewater treatment plant. Remaining with two different ionization interfaces, ESI and APPI, in both polarities, a non-targeted screening approach led to a total number of 146 HS (each with a minimum number of 4 members), with a molecular mass of up to 1200 detected in the final effluent. Of the 146 HS, ca 15% could be associated with suspect hits and approximately 25% with transformation products of suspects. Tentative characterization or probable chemical structure could be assigned to almost half of the findings. In positive ionization mode various sugar derivatives with differing side chains, for negative mode structures with sulfonic acids, could be characterized. The number of detected HS decreased significantly over the three treatment stages. For HS detectable also in the biological and oxidative treatment stages, a change in HS distribution towards to lower mass range was often observed.

Introduction and aim Exposure to some insecticides may cause airway obstruction, but existing evidence is limited by cross-sectional designs and inadequate confounder control. We investigated the relation between organophosphate and carbamate insecticides and pulmonary function in a prospective study accounting for important confounders.
Methods In a cohort of 364 smallholder farmers in Uganda (69% women), participants underwent pre-bronchodilator spirometry at baseline (September/October 2018) and at two follow-up visits (November/December 2018 and January/February 2019). Exposure to carbamate and organophosphate insecticides was assessed using haemoglobin-adjusted erythrocyte acetylcholinesterase (AChE/Hb). Less than 3% of participants were lost to follow-up. We calculated Z-scores for FEV₁, FVC and FEV₁/FVC using the Global Lung Function Initiative equations. Data were analysed in linear mixed and fixed effect models accounting for family relationships and repeated measures of exposure and outcome.
Results Low AChE/Hb was significantly associated with low FEV₁ Z-score in both unadjusted and adjusted analyses. Compared with individuals with AChE/Hb 25.90 U/g (50^th percentile, reference), those with lower AChE/Hb 24.50 U/g (35^th percentile) had mean FEV₁ Z-score 0.045 (0.003 to 0.087) lower, and persons with higher AChE/Hb 27.30 U/g (65^th percentile) had a mean FEV₁ Z-score 0.043 (-0.002 to 0.087) higher compared with the reference. Similar, but numerically smaller and statistically non-significant effects were seen for Z-scores of FVC and FEV₁/FVC.
Conclusion Exposure to organophosphate and carbamate insecticides may lead to lung function decline. Our results add to the growing evidence of health effects in relation to exposure to organophosphate and carbamate insecticides, underlining the importance of minimising exposure.

In this work, emissions of active pharmaceutical ingredients (APIs) from formulating pharmaceutical industries (FPIs) were investigated for the first time based on detailed production information and compared to overall API emissions in wastewater treatment plant (WWTP) effluents. At two municipal WWTPs, both receiving wastewater from several FPIs, two months' daily effluent samples were collected and measured using liquid chromatography high-resolution mass spectrometry (LC-HRMS). Thirty-three APIs formulated during the sampling period as well as >120 organic contaminants commonly present in WWTP effluents were quantified. On the basis of their time patterns and manufacturing data, industrial contributions were found for 22 of 26 APIs (85%) detected in the samples and processed by the FPIs. API emissions from FPIs led to daily concentration increases of up to 300-fold, despite pretreatment of the industrial wastewater. However, emissions from FPIs seemed to depend on the type of formulating activity, with granulation and mixing being most prone to API losses. Losses from FPIs were responsible for the highest concentrations and for up to 60% of the daily total API emissions measured. Furthermore, screening for suspects in LC-HRMS data resulted in the detection of unexpected emissions from FPIs, demonstrating the value of these data to comprehensively assess industrial API losses. Overall, this study showed that FPIs were relevant contributors of APIs emitted in the WWTP effluents, although only a minor fraction (<1%) of the total processed API quantity was lost to the wastewater, and despite the small percentage (<5%) of FPI wastewater compared to the total wastewater flow.

Gemäss Verfassungsauftrag ist die Schweizer Landwirtschaft stark multifunktional ausgerichtet. Diese Multifunktionalität kann Zielkonflikte auslösen zwischen der sicheren Versorgung der Bevölkerung, der Erhaltung der natürlichen Lebensgrundlagen, der Pflege der Kulturlandschaft und der dezentralen Besiedlung des Landes. Um derartige Zielkonflikte systematisch zu analysieren, künftige Forschungsvorhaben zu priorisieren und Massnahmen zur Ressourcenschonung zu formulieren, haben die Eawag, das Wasserforschungsinstitut des ETH-Bereichs, und das BLW unter Einbezug von Agroscope 2013 bis 2015 das Projekt Zukunftsfähige, gewässerschonende landwirtschaftliche Produktion in der Schweiz (AProWa) durchgeführt. Methodisch wurde die umfassende Auslegeordnung in eine multikriterielle Entscheidungsanalyse (MCDA) eingebettet. Folgende Resultate wurden durch das Projekt erarbeitet:
1. Eine systematische Aufstellung und Gliederung von Produktionszielen (z. B. hohe Ertragsmenge) und Erhaltungszielen (z. B. geringe Schadstoffkonzentrationen im Grundwasser) in Form einer Zielhierarchie.
2. Ein Vorschlag an messbaren Indikatoren («Attribute» genannt) zur Quantifizierung der Zielerreichung.
3. Eine Sammlung von relevanten Massnahmen im Bereich einer gewässerschonenden Landwirtschaft.
4. Testen des MCDA-Ansatzes zur quantitativen Bewertung verschiedener Handlungsoptionen hinsichtlich ihrer Wirkungen im Gesamtsystem.
5. Vorschläge für zukünftige Forschungsfragen basierend auf dem aufgezeigten Forschungsbedarf.
6. Vorschläge für den weiteren Einsatz der MCDA-Methode in der Praxis. [ ...]