An effective and sensitive method for the analysis of 1,4-dioxane in water has been available since 2008 (EPA 522). This method is increasingly being applied to investigate the distribution of ...1,4-dioxane in the aquatic environment. However, there is a need for more information about the possible occurrence of 1,4-dioxane in groundwater in Europe in general, and in Germany in particular, where virtually no data have been collected so far. The possible contamination of groundwater with 1,4-dioxane is of relevance to Germany because up to 70% of Germany's drinking water is obtained from groundwater and about 17% from river bank filtrate, which contains variable proportions of groundwater. The aim of the present study is to investigate selected and representative groundwater sites in Germany that have suspected occurrences of 1,4-dioxane. Five of the sites are well known for their volatile chlorinated hydrocarbon contamination, two sites have representative landfill leachate characteristics, and one site is negatively impacted by a detergent manufacturing plant. The presence of 1,4-dioxane was observed at each of these sites. Measured maximum concentration values ranged from 0.15μg/L to 152μg/L. An aquifer containing a trichloroethylene (TCE) plume with 1,4-dioxane as a co-contaminant was investigated in more detail. A perfect match was found between the concentrations of 1,4-dioxane and TCE in the vertical and horizontal distribution profiles. The results indicate the necessity for investigating groundwater contamination by 1,4-dioxane at sites with known 1,1,1-trichloroethane (TCA) and TCE contaminations, in landfill leachates, and at sites of detergent production.
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•1,4-Dioxane was evaluated in German groundwater and was detected at all sites tested.•Max. concentrations of 1,4-dioxane exceed the 0.1μg/L assessment value at each site.•Highest concentration of 1,4-dioxane was detected in a VCH plume (152μg/L).•Depth distribution of 1,4-dioxane exhibited strong correlation with TCE.
This guidance document provides a tiered framework for risk assessors and facilitates risk managers in making decisions concerning the approval of active substances (AS) that are chemicals in plant ...protection products (PPPs) and biocidal products, and authorisation of the products. Based on the approaches presented in this document, a conclusion can be drawn on the impact of water treatment processes on residues of the AS or its metabolites in surface water and/or groundwater ed for the production of drinking water, i.e. the formation of transformation products (TPs). This guidance enables the identification of actual public health concerns from exposure to harmful compounds generated during the processing of water for the production of drinking water, and it focuses on water treatment methods commonly used in the European Union (EU). The tiered framework determines whether residues from PPP use or residues from biocidal product use can be present in water at water ion locations. Approaches, including experimental methods, are described that can be used to assess whether harmful TPs may form during water treatment and, if so, how to assess the impact of exposure to these water treatment TPs (tTPs) and other residues including environmental TPs (eTPs) on human and domesticated animal health through the consumption of TPs via drinking water. The types of studies or information that would be required are described while avoiding vertebrate testing as much as possible. The framework integrates the use of weight‐of‐evidence and, when possible alternative (new approach) methods to avoid as far as possible the need for additional testing.
Since our comprehensive investigation of finished drinking water in Germany obtained from managed aquifer recharge systems in the period 2015-2016, which revealed widespread contamination with ...1,4-dioxane, mitigation measures (integration of AOP units, shutdown or alteration of production processes) have been implemented at some sites. In this study, we conducted follow-up tests on surface water concentrations and associated finished drinking water concentrations in 2017/2018, to evaluate the effectiveness of these measures. Our findings demonstrate that the emission mitigation measures had considerably reducing effects on the average 1,4-dioxane drinking water concentrations for some of the previously severely affected areas (Lower Franconia: -54%, Passau: -88%). Conversely, at notoriously contaminated sites where neither monitoring nor mitigation measures were introduced, the drinking water concentrations stagnated or even increased. Drinking water concentrations determined via a modified US EPA method 522 ranged from below LOQ (0.034 μg/L) up to 1.68 μg/L in all drinking water samples investigated. In river water samples, the maximum concentration exceeded 10 μg/L. Effluents of wastewater treatments plants containing 1,4-dioxane (5 μg/L–1.75 mg/L) were also analyzed for other similar cyclic ethers by suspected target screening. Thus, 1,3-dioxolane and three other derivatives were tentatively identified in effluents from the polyester processing or manufacturing industry. 1,3-Dioxolane was present in concentrations >1.2 mg/L at one site, exceeding up to sevenfold the 1,4-dioxane concentration found there. At another site 2-methyl-1,3-dioxolane was still found 13 km downstream of the discharge point, indicating that ethers analogous to 1,4-dioxane should be further considered regarding their occurrence and fate in wastewater treatment and the aquatic environment.
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•Field study in German FDW/rivers: mitigation measures affect 1,4-dioxane levels.•Point source elimination reduced 1,4-dioxane levels in associated FDW up to ~90%.•River concentrations up to >10 μg/L measured in regions with no dioxane-strategy•Lower river discharges 2018 aggravated 1,4-dioxane loads.•Dioxane-likes in WWTP discharges and related rivers: 2-Methyl-1,3-dioxolane most abundant/persistent
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•Final drinking water, obtained by MAR, was tested for 1,4-dioxane throughout Germany.•Managed Aquifer Recharge Systems (MAR) are decisive for 1,4-dioxane in German FDW.•98 out of 125 ...drinking water samples contained 1,4-dioxane of 0.034 to 2.05 μg/L.•Source water pollution, blending and exact method of MAR are key factors identified.•Bank filtration exhibits to be less favorable than artificial groundwater recharge.
1,4-Dioxane, a cyclic ether that has been classified as a class 2B carcinogen by the US-EPA, is a substance of growing environmental concern because of its abundant occurrence in surface waters worldwide. Its high polarity and low biodegradability hamper its retardation in aquifer systems. Previous investigations in Germany have shown that 1,4-dioxane is already widely distributed in rivers and can be found in groundwater at contamination sites. Therefore, the present study shall provide an overview of the Germany-wide distribution of 1,4-dioxane in finished drinking water (FDW) obtained by managed aquifer recharge (MAR) systems. Thus, we investigated the 1,4-Dioxane levels in FDW obtained by MAR, such as river bank filtration (RBF) or artificial groundwater recharge (AGR), in regions that are supplied by surface water bodies (mainly rivers) with already known 1,4-dioxane contaminations. In total, 125 FDW samples and 33 samples of corresponding surface waters were analyzed for 1,4-dioxane content using solid phase extraction followed by gas chromatography–mass spectrometry (SIM-mode) using a slight modification to US-EPA method 522. About 80% of the investigated FDW samples contained 1,4-dioxane at levels exceeding the limit of quantification (0.034 μg/L); the maximum value was 2.05 μg/L. However, a maximum concentration of 3 μg/L was obtained in the surface water samples. Three main factors were associated with elevated levels of 1,4-dioxane in the FDW: A significant 1,4-dioxane contamination of the associated surface water, the application of RBF instead of AGR, and the proportion of available unpolluted groundwater and/or reservoir water blended in the individual waterworks. The results show that 1,4-dioxane should be critically monitored during FDW production by means of MAR not only in Germany. The findings are also of relevance to neighboring countries depending on the same river systems and for research in the field of small mobile substances in drinking water production in general.
To estimate the prevalence of diabetes due to diseases of the exocrine pancreas (DEP) using data of the multicentre diabetes patient follow-up registry. Moreover, we aimed at comparing individuals ...with diabetes due to DEP to individuals with type 1 and type 2 diabetes.
Individuals with DEP, type 1 or type 2 diabetes ≥18 years of age were studied. We aggregated the most recent treatment year per patient and used propensity scores to match diabetes due to DEP to type 1 and type 2 diabetes. Matching was conducted one-to-one with sex, age, diabetes duration, migration background and the German index of socioeconomic deprivation as covariates.
We identified 7,093 (1.6%) individuals with diabetes due to DEP. In the matched cohort DEP-type 1 diabetes we observed a similar daily insulin dose (0.62 IU/kg (95% confidence interval:0.60–0.63), 0.60 IU/kg (0.58–0.62)) and significant differences regarding microvascular (41.0% (39.7–42.2), 45.3% (44.0–46.6)), and macrovascular disease (16.6% (15.7–17.6), 14.7% (13.8–15.6)). HbA1c (8.2% (8.1–8.3), 7.9% (7.8–8.0)), daily insulin dose (0.60 IU/kg (0.58–0.62), 0.56 IU/kg (0.54–0.58)) and event rates of severe hypoglycemia (23.9 events/100 PY (21.4–26.8), (9.5 events/100 PY (8.0–11.2)) were significantly higher in individuals with diabetes due to DEP compared to type 2 diabetes.
Using registry data, rare diabetes types such as diabetes due to DEP can be studied with a significant sample size. Our study identified differences and similarities between adult individuals with DEP related diabetes and type 1 or type 2 diabetes.
Recombinant factor XIIIa (FXIIIa), produced in Saccharomyces cerevisiae, was recovered as a fully active cytosolic component and rigorously compared to natural F XIIIa from human placenta with ...respect to physicochemical and functional properties. Identical parameters were found in SDS polyacrylamide gel electrophoresis, analytical ultracentrifugation and HPLC gel filtration, and all spectral characteristics including derivative UV absorbance, fluorescence and circular dichroism were identical. Similarly, the interaction of both proteins with polyclonal antibodies directed against the entire FXIIIa or its N-terminal 4 kD activation peptide were identical. Furthermore, thrombin cleavage and fibrin cross-linking showed indistinguishable patterns. The only difference we observed was with respect to endgroup analysis. The recombinant protein is homogeneous, whereas placental FXIIIa shows multiple electrophoretic bands caused by microheterogeneity in the C-terminal part of the protein.
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