Geochemical evidence for the link between sulfate reduction, sulfide oxidation and phosphate accumulation in a Late Cretaceous upwelling system.

BACKGROUND: On Late Cretaceous Tethyan upwelling sediments from the Mishash/Ghareb Formation (Negev, Israel), bulk geochemical and biomarker analyses were performed to explain the high proportion of phosphates in the lower part and of organic matter (OM) preserved in upper parts of the studied section. The profile is composed of three facies types; the underlying Phosphate Member (PM), the Oil Shale Member (OSM) and the overlying Marl Member (MM). RESULTS: Total organic carbon (TOC) contents are highly variable over the whole profile reaching from 0.6% in the MM, to 24.5% in the OSM. Total iron (TFe) varies from 0.1% in the PM to 3.3% in the OSM. Total sulfur (TS) ranges between 0.1% in the MM and 3.4% in the OSM, resulting in a high C/S ratio of 6.5 in the OSM section. A mean proportion of 11.5% total phosphorus (TP) in the PM changed abruptly with the facies to a mean value of only 0.9% in the OSM and the MM. The TOC/TOCOR ratios argue for a high bacterial sulfate reduction activity and in addition, results from fatty acid analyses indicate that the activity of sulfide-oxidizing activity of bacteria was high during deposition of the PM, while decreasing during the deposition of the OSM. CONCLUSIONS: The upwelling conditions effected a high primary productivity and consequently the presence of abundant OM. This, in combination with high sulfate availability in the sediments of the PM resulted in a higher sulfide production due to the activity of sulfate-reducing bacteria. Iron availability was a limiting factor during the deposition of the whole section, affecting the incorporation of S into OM. This resulted in the preservation of a substantial part of OM against microbial degradation due to naturally-occurring sulfurization processes expressed by the high C/S ratio of 6.5 in the OSM. Further, the abundant sulfide in the pore water supported the growth of sulfide-oxidizing bacteria promoting the deposition of P, which amounted to as much as 15% in the PM. These conditions changed drastically from the PM to the OSM, resulting in a significant reduction of the apatite precipitation and a high concentration of reactive S species reacting with the OM.

Effect-directed identification of endocrine disruptors in plastic baby teethers.

Concerns have been raised regarding the human health effects of endocrine disrupting chemicals (EDCs), many of which are associated with and leaching from plastics. As infants are particularly vulnerable to EDCs, we have investigated whether plastic teethers for babies represent a relevant source of exposure. Applying effect-directed analysis, we use bioassays to screen teethers, toys used to soothe a baby's teething ache, for endocrine activity and chemical analysis to identify the causative compounds. We detected significant endocrine activity in two of 10 plastic teethers. Those samples leached estrogenic and/or antiandrogenic activity as detected in the Yeast Estrogen Screen and Yeast Antiandrogen Screen. After sample fractionation, gas chromatography-mass spectrometry non-target screening revealed that methyl-, ethyl- and propylparaben were responsible for the observed estrogenic and antiandrogenic activity in one product. The second product is likely to contain at least six different antiandrogenic compounds that remain so far unidentified. This study demonstrates that plastic teethers can be a source of infant exposure to well-established and unknown EDCs. Because of their limited value to the product, but potential toxicity, manufacturers should critically revisit the use of parabens in plastic teethers and further toys. Moreover, plastic teethers might leach EDCs that escape routine analysis and, thus, toxicological evaluation. The resulting uncertainty in product safety poses a problem to consumers, producers and regulators that remain to be resolved.

Using ICP-qMS to trace the uptake of nanoscale titanium dioxide by microalgae-potential disadvantages of vegetable reference material.

As nanoscale materials have gained in economic importance over recent years, concerns about accumulation in the environment and, consequently, analysis of nanoparticles in biological material have increasingly become the focus of scientific research. A nanomaterial used in a wide range of food, consumer and household products is titanium dioxide (nTiO2). Monitoring of nTiO2 via determination of elemental titanium (Ti) can be very challenging because of a variety of possible interferences. This work describes problems during the development of a quantification method for titanium dioxide (TiO2) using inductively coupled plasma-quadrupole mass spectrometry (ICP-qMS). To evaluate the analytical method, certified vegetable reference material NCS DC 73349 was used. Interestingly, measurements of NCS DC 73349 seemed to result in acceptable recovery values-however, this was without considering interferences or conceivable differences in the natural isotopic abundance of the certified titanium calibration solution and NCS DC 73349. Actually, recoveries were lower than initially assumed. The potential interferences causing augmented recovery could be attributed to the presence of the elements sulfur (S) and phosphorus (P), which were able to form oxide ions and nitrogen-interfering species. The effect of such interfering cluster ions could be prevented by dry ashing as a sample preparation step, to evaporate S and P, before digestion with aqua regia in a high-pressure asher (HPA). Final practicability of the analysis method was proved by monitoring the uptake of nTiO2 by the microalgae Scenedesmus acutus in an environmental exposure study.

Limited waterborne acute toxicity of native polycyclic aromatic compounds from coals of different types compared to their total hazard potential.

Coals contain native polycyclic aromatic compounds (PACs), which include polycyclic aromatic hydrocarbons (PAHs), and heterocyclic aromatic compounds (NSO-PACs) in considerably varying amounts up to 2500 mg/kg. Whereas PAC bioavailability and toxicity from coals are generally considered to be low, few studies have considered potential variations arising from the composition of different coal types including native PAC content. In the present study, fine particles of different coal types exhibiting variable properties were systematically investigated regarding their PAC bioavailability. PAH content reached up to 79 mg/kg EPA-PAH and 865 mg/kg total PAH. Determination of the toxic potential of extracted PACs in bioassays showed inhibition of Caenorhabditis elegans reproduction (up to 94%) and increased mortality of Danio rerio embryos (up to 100%) after exposure to extracts from lignite, sub-bituminous, and bituminous coals. Anthracite extracts showed no effects. Contact assays using whole coal samples revealed no toxicity to D. rerio embryos in any of the coal samples, suggesting low bioavailability of PACs. In contrast, C. elegans reproduction was inhibited by direct coal contact; however, the observed toxicity probably resulted from other coal effects. The results suggest that despite the high toxic potential of PACs present, their bioavailability from different coal types is very limited and independent of coal properties and native PAH content.

In vitro investigations of platinum, palladium, and rhodium mobility in urban airborne particulate matter (PM10, PM2.5, and PM1) using simulated lung fluids.

Environmental concentrations of platinum group elements (PGE) have been increasing since the introduction of automotive catalytic converters to control harmful emissions. Assessments of the human health risks of exposures to these elements, especially through the inhalation of PGE-associated airborne particulate matter (PM), have been hampered by a lack of data on their bioaccessibility. The purpose of this study is to apply in vitro methods using simulated human lung fluids [artificial lysosomal fluid (ALF) and Gamble's solution] to assess the mobility of the PGE, platinum (Pt), palladium (Pd), and rhodium (Rh) in airborne PM of human health concern. Airborne PM samples (PM(10), PM(2.5), and PM(1)) were collected in Frankfurt am Main, Germany. For comparison, the same extraction experiments were conducted using the standard reference material, Used Auto Catalyst (monolith) (NIST 2557). Pt and Pd concentrations were measured using isotope dilution ICP-Q-MS, while Rh was measured directly with ICP-Q-MS (in collision mode with He), following established matrix separation and enrichment procedures, for both solid (filtered residues) and extracted sample phases. The mobilized fractions measured for PGE in PM(10), PM(2.5), and PM(1) were highly variable, which can be attributed to the heterogenic nature of airborne PM and its composition. Overall, the mobility of PGE in airborne PM samples was notable, with a mean of 51% Rh, 22% Pt, and 29% Pd present in PM(1) being mobilized by ALF after 24 h. For PM(1) exposed to Gamble's solution, a mean of 44% Rh, 18% Pt, and 17% Pd was measured in solution after 24 h. The mobility of PGE associated with airborne PM was also determined to be much higher compared to that measured for the auto catalyst standard reference material. The results suggest that PGE emitted from automotive catalytic converters are likely to undergo chemical transformations during and/or after being emitted in the environment. This study highlights the need to conduct bioaccessibility experiments using samples collected in the field to enable an adequate assessment of risk.

Impact of wastewater treatment plant discharge of lidocaine, tramadol, venlafaxine and their metabolites on the quality of surface waters and groundwater.

The presence of the anesthetic lidocaine (LDC), the analgesic tramadol (TRA), the antidepressant venlafaxine (VEN) and the metabolites O-desmethyltramadol (ODT) and O-desmethylvenlafaxine (ODV) was investigated in wastewater treatment plant (WWTP) effluents, in surface waters and in groundwater. The analytes were detected in all effluent samples and in only 64% of the surface water samples. The mean concentrations of the analytes in effluent samples from WWTPs with wastewater from only households and hospitals were 107 (LDC), 757 (TRA), 122 (ODT), 160 (VEN) and 637 ng L(-1) (ODV), while the mean concentrations in effluents from WWTPs treating additionally wastewater from pharmaceutical industries as indirect dischargers were for some pharmaceuticals clearly higher. WWTP effluents were identified as important sources of the analyzed pharmaceuticals and their metabolites in surface waters. The concentrations of the compounds found in surface waters ranged from

Implementation of initial emission mitigation measures for 1,4-dioxane in Germany: Are they taking effect?

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.

1,4-Dioxane contamination of German drinking water obtained by managed aquifer recharge systems: Distribution and main influencing factors.

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.

Distributions of organophosphate flame retardants (OPFRs) in three dust size fractions from homes and building material markets.

The distributions of organophosphate flame retardants (OPFRs) in various size fractions of indoor dust samples from homes (H; n = 18) and building material markets (B; n = 7) in the Rhine/Main region of Germany were investigated. Three particle size fractions (F1: 150-200 µm, F2: 63-150 µm, and F3: <63 µm) and bulk dust (BD) subsamples (<200 µm) of each sample were analyzed for 10 OPFRs. On average, the total OPFR concentrations (∑10OPFR) in bulk dust and all three size fractions from building material markets were 133, 153, 196, and 88.0 µg/g in subsamples B-BD, B-F1, B-F2, and B-F3. These concentrations were at least five times higher than those in bulk dust and all three size fractions from homes, with values of 19.3, 17.2, 19.5, and 18.7 µg/g for subsamples H-BD, H-F1, H-F2, and H-F3, respectively. Tris(2-chloroisopropyl)phosphate (TCIPP) was the dominant congener in dust from building material markets, contributing over 91% to the ∑10OPFR of B-BD and all particle size fractions. Meanwhile, both tris(2-butoxyethyl)phosphate (TBOEP) and TCIPP were abundant in dust from homes, respectively contributing 28%-41% and 31%-43% to the ∑10OPFR of H-BD and all particle size fractions. Most of the OPFR concentrations showed no consistent trend with particle size. However, TCIPP was more likely to be enriched in F2. Microscopic examination indicated that TCIPP in indoor dust mainly originated from abraded fragments of commercial products. In contrast, TBOEP accumulated in F3, related to direct transfer of floor-care products to fine dust particles. The concentrations of OPFRs were not significantly correlated with total organic carbon contents in any particle size fraction. However, evaluation of their mass contributions showed that more than 85% of OPFRs accumulated in particles smaller than 150 µm, indicating that this particle size fraction is most suitable for monitoring of OPFRs.

Examination of paraben release from baby teethers through migration tests and GC-MS analysis using a stable isotope dilution assay.

Parabens and sorbic acid are commonly used as food preservatives due to their antimicrobial effect. However, their use in foods for infants and young children is not permitted in the European Union. Previous studies found these compounds in some gel-filled baby teethers, whereby parabens, which are well-known as endocrine disruptors, were identified in the polymer-based chewing surface consisting of ethylene-vinyl acetate (EVA). To assess the exposure of infants and young children to these products, the application of parabens in teethers should be thoroughly investigated. Therefore, the present study aimed to apply a representative migration test procedure combined with an accurate analytical method to examine gel-filled baby teethers without elaborate sample preparation, high costs, and long processing times. Accordingly, solid-phase extraction (SPE), in combination with a stable isotope dilution assay (SIDA) and subsequent gas chromatography-mass spectrometry (GC-MS) for analysis of methyl-, ethyl-, and n-propylparaben (MeP, EtP, and n-PrP), was found to be well-suited, with recoveries ranging from 93 to 99%. The study compared the release of these parabens from intact teether surfaces into water and saliva simulant under real-life conditions, with total amounts of detected parabens found to be in the range of 101-162 µg 100 mL-1 and 57-148 µg 100 mL-1, respectively. Furthermore, as a worst-case scenario, the release into water was examined using a long-term migration study.

Analysis of benzene, toluene, ethylbenzene, xylenes and n-aldehydes in melted snow water via solid-phase dynamic extraction combined with gas chromatography/mass spectrometry.

The present study describes a method based on headspace-solid-phase dynamic extraction (HS-SPDE) followed by GC/MS for the qualitative and quantitative analysis of benzene, toluene, ethylbenzene, o-, m- and p-xylene (BTEX), and n-aldehydes (C(6)-C(10)) in water. To enhance the extraction capability of the HS-SPDE a new cooling device was tested that controls the temperature of the SPDE needle during extraction. Extraction and desorption parameters such as the number of extraction cycles, extraction temperature, desorption volume and desorption flow rate have been optimized. Detection limits for BTEX ranged from 19 ng/L (benzene) to 30 ng/L (m/p-xylene), while those for n-aldehydes ranged from 21 ng/L (n-heptanal) to 63 ng/L (n-hexanal). At a concentration level of 2 microg/L, the relative standard deviations (RSDs) for BTEX ranged from 3.9% (benzene) to 15.3% (ethylbenzene), while RSDs for n-aldehydes were between 6.1% (n-octanal) and 16.5% (n-hexanal) (n=7). Best results were obtained when the analyzed water samples were heated to 50 degrees C. At a water temperature of 70 degrees C GC responses decreased for all analyzed compounds. At a defined water temperature, a significant improvement of the GC response was achieved by cooling of the SPDE fiber during water extraction in comparison to an extraction keeping the fiber at room temperature. Evaluating the extraction cycles, for BTEX, the sensitivity was almost similar using 20, 40 and 60 extraction cycles. In contrast, the highest GC responses for n-aldehydes were achieved by the use of 60 extraction cycles. Optimizing the desorption parameters, best results were achieved using the smallest technical available desorption volume of 500 microL and the highest technical desorption flow rate of 50 microL/s. The method was applied to the analysis of melted snow samples taken from the Jungfraujoch, Switzerland (3580 m asl), revealing the presence of BTEX and aldehydes in snow.

Endocrine disruptors in freshwater streams of Hesse, Germany: changes in concentration levels in the time span from 2003 to 2005.

Four small freshwater streams in the region known as Hessisches Ried in Germany were investigated with respect to the temporal and spatial concentration variations of the endocrine disruptors bisphenol A (BPA), 4-tert-octylphenol (4-tert-OP), and the technical isomer mixture of 4-nonylphenol (tech.-4-NP). Measured concentrations of the target compounds in the river water samples ranged from <20 ng/l to 1927 ng/l, <10 ng/l to 770 ng/l, and <10 ng/l to 420 ng/l for BPA, 4-tert-OP and tech.-4-NP, respectively. BPA levels were, with the exception of two samples, below the predicted no-effect concentration (PNEC) for water organisms. Tech.-4-NP concentrations showed a significant tendency of decreasing concentrations during the sampling period. This is mainly attributed to the implementation of the European Directive 2003/53/EG, which restricts both the marketing and use of nonylphenols. Results from the analysis of additionally collected water samples from sewage treatment plant (STP) effluents indicate that the STPs cannot be the only sources for tech.-4-NP found in the river water.

Benzene, alkylated benzenes, chlorinated hydrocarbons and monoterpenes in snow/ice at Jungfraujoch (46.6 degrees N, 8.0 degrees E) during CLACE 4 and 5.

Benzene, alkylated benzenes, chlorinated hydrocarbons and monoterpenes were measured in snow/ice collected directly in-cloud at Jungfraujoch (3580 m asl) in February and March 2005 and 2006 during the CLoud and Aerosol Characterization Experiments CLACE 4 and CLACE 5. Melted snow/ice samples were analyzed by headspace-solid-phase-dynamic-extraction (HS-SPDE) followed by gas chromatography/mass spectrometry (GC/MS). Generally, there was a tendency in the results that higher concentrations were found after longer precipitation-free periods, suggesting that higher concentrations in snow/ice may be caused by the washout effect of precipitation. High concentration variations in snow/ice samples taken at the same time at the same place highlight the heterogeneous nature of snow/ice. Air concentrations calculated by scavenging ratios and measured snow/ice values markedly exceed the typically reported concentrations of benzene and alkylbenzenes in air (Li Y, Campana M, Reimann S, Schaub KS, Staehlin J, Peter T. Hydrocarbon concentrations at the alpine mountain sites Jungfraujoch and Arosa. Atmos Environ 2005;39:1113-27). This argues for an efficient snow/ice scavenging of those compounds from the atmosphere during precipitation formation.

Occurrence and temporal variations of the xenoestrogens bisphenol A, 4-tert-octylphenol, and tech. 4-nonylphenol in two German wastewater treatment plants.

GOAL, SCOPE, AND BACKGROUND: The xenoestrogens bisphenol A, 4-tert-octylphenol, and the technical isomer mixture of 4-nonylphenol (tech. 4-nonylphenol) belong to the group of chemicals which are called endocrine disrupters due to their property of causing hormonal dysfunctions in the endocrine system of organisms at very low concentrations. Bisphenol A, 4-tert-octylphenol, and the tech. 4-nonylphenol (mixture of isomers) were determined in water samples collected from the influent and effluent of two German wastewater treatment plants (WWTP) during a long-time sampling period from February 2003 till August 2005 to assess their occurrence and temporal variations in WWTPs. METHODS: The compounds were extracted and concentrated from water by solid-phase extraction (SPE) using Bond Elut PPL cartridges and quantified by use of gas chromatography-mass spectrometry (GC-MS). RESULTS: The influent concentrations were as follows: Bisphenol A < limit of detection of the method (< ldm)--12,205 ng L(-1), tech. 4-nonylphenol < ldm--10,186 ng L(-1), and 4-tert-octylphenol 39-1,495 ng L(-1). The measured effluent concentrations were lower with values in the range of < ldm--7,625 ng L(-1) for bisphenol A, < ldm--14,444 ng L(-1) for tech. 4-nonylphenol, and < ldm--392 ng L(-1) for 4-tert-octylphenol. All target compounds were largely eliminated during the wastewater treatment process. The elimination efficiency varied between 73% and 93%. DISCUSSION: All analytes show highly fluctuating influent concentrations with very high peak concentrations at particular sampling times. The variation of effluent concentrations is by far lower than the variation of influent concentrations. For tech. 4-nonylphenol, a significant temporal concentration variation has been detected with very high concentrations up to the microgram-per-liter level in the time from February 2003 till July 2003 and clearly decreasing concentrations in the time from June 2004 till August 2005. This corresponds well with the implementation of Directive 2003/53/EC (nonylphenol and nonylphenol ethoxylates in the European Union "may not be placed on the marked or used as a substance or constituent of preparations in concentrations equal or higher than 0.1% by mass") from January 2005 on. Bisphenol A is present in the effluent samples in a wide range of concentrations from below the detection limit to high concentrations up to the microgram-per-liter level. For 4-tert-octylphenol, no particular trend of concentration development has been observed. CONCLUSIONS: Combined SPE and GC-MS proved to be an efficient method to identify and quantify polar organic compounds in environmental samples. With respect to the concentrations measured in the present study, bisphenol A sometimes is the prominent compound in influent samples. Neither bisphenol A nor 4-tert-octylphenol or tech. 4-nonylphenol show seasonal variations. However, there was a significant general trend of decreasing concentrations of tech. 4-nonylphenol in influent and effluent samples from both WWTPs which probably reflects the implementing Directive 2003/53/EC. RECOMMENDATIONS AND PERSPECTIVES: Further research is needed to investigate whether the observed decrease of tech. 4-nonylphenol concentrations in German WWTPs since June 2004 will continue further on. The reason for the high effluent concentrations of bisphenol A in only a few samples has to be clarified in further research. The results from this study provide insight into the concentration development of the xenoestrogens bisphenol A, tech. 4-nonylphenol, and 4-tert-octylphenol in WWTPs in the time span between 2003 and 2005.

1,4-Dioxane pollution at contaminated groundwater sites in western Germany and its distribution within a TCE plume.

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.

Organophosphate flame retardants (OPFRs) in indoor and outdoor air in the Rhine/Main area, Germany: comparison of concentrations and distribution profiles in different microenvironments.

The concentrations of 9 organophosphate flame retardants (OPFRs) were determined in 56 indoor and 9 outdoor air samples in the Rhine/Main area in Germany. The indoor samples were collected from seven different indoor microenvironments including private cars, private homes, floor/carpet stores, building material markets, schools, offices, and day care centers, while outdoor samples were simultaneously collected close to the indoor sampling locations. The total OPFR concentrations (∑OPFRs) in indoor air ranged from 3.30 to 751.0 ng/m3 with a median of 40.23 ng/m3, which was approximately eight times higher than those in outdoor air (median 5.38 ng/m3), indicating that sources of OPFRs predominate in the indoor environment. Tris(2-chloroisopropyl)phosphate (TCPP), tris(isobutyl)phosphate (TiBP), and tributyl phosphate (TnBP) were the dominating compounds both in indoor and outdoor air. The median concentration of ∑OPFRs in private cars (180.3 ng/m3) was significantly higher than that in private homes (12.51 ng/m3), schools (36.23 ng/m3), day care centers (31.80 ng/m3), and building material markets (31.17 ng/m3) (p < 0.05). Distribution profiles of OPFRs varied among different indoor microenvironments, which are evidenced by dominating indoor air concentrations of non-Cl-OPFRs in day care centers, floor/carpet stores, schools, and of Cl-OPFRs in other indoor microenvironments. Multivariate analyses revealed three distinct groups for OPFRs, i.e., TiBP/TnBP, TEP/TCEP/TDCPP, and TCPP, whose concentrations were closely associated with the distribution profiles and pollution characteristics of materials predominating in different indoor microenvironments.

Comparison of MTBE concentrations in groundwater of urban and nonurban areas in Germany.

The occurrence of the gasoline oxygenate methyl tert-butyl ether (MTBE) in groundwater samples from known fuel-contaminated sites (n=29 samples), nonurban (n=74) and urban sites (n=67) in Germany was investigated. The analyses revealed detection frequencies of 58% (contaminated sites), 24% (nonurban sites) and 63% (urban sites) at a detection limit of 0.01 microgL(-1). Median (maximum) MTBE concentrations were calculated for nonurban and urban samples as 0.18 microgL(-1) (2.2 microgL(-1)) and 0.06 microgL(-1) (48 microg L(-1)). The data from nonurban samples revealed MTBE detections mainly at public supply wells with higher pumping rates than monitoring wells. MTBE was more frequently detected in urban samples, most probably due to the higher atmospheric input and direct liquid emissions from motorways or gas stations. Higher concentrations above 1.0 microgL(-1) in urban areas were found in wells located at industrial sites, where also a MTBE plume was accidentally detected during the study. The prevalence of MTBE in shallow aquifers was comparable to those in the USA.

Methyl tert-butyl ether (MTBE) in finished drinking water in Germany.

In the present study 83 finished drinking water samples from 50 cities in Germany were analyzed for methyl tert-butyl ether (MTBE) content with a detection limit of 10 ng/L. The detection frequency was 46% and the concentrations ranged between 17 and 712 ng/L. Highest concentrations were found in the community water systems (CWSs) of Leuna and Spergau in Saxony-Anhalt. These CWSs are supplied with water possibly affected by MTBE contaminated groundwater. MTBE was detected at concentrations lower than 100 ng/L in drinking water supplied by CWSs using bank filtered water from Rhine and Main Rivers. The results from Leuna and Spergau show that large groundwater contaminations in the vicinity of CWSs pose the highest risk for MTBE contamination in drinking water. CWSs using bank filtered water from Rhine and Main Rivers are susceptible to low MTBE contaminations in finished drinking water. All measured MTBE concentrations were below proposed limit values for drinking water.

Metal and metalloid accumulation in cultivated urban soils: A medium-term study of trends in Toronto, Canada.

This study aims to examine the elemental enrichment patterns in low to medium traffic areas over a three year period in Toronto, Canada. Soils were sampled at three locations with different volumes of traffic between 2010 and 2013. A range of elements, including V, Cr, Mn, Cu, Cd, As, Sb and Pb, were measured in acid digested samples using ICP-MS. While the concentrations of Cd, Sb and Pb were found to be relatively low, a significant, albeit small increase in their levels over time was determined for all sites. For the low traffic areas, median Cd, Sb and Pb concentrations increased from 0.18mg Cd/kg, 0.14mg Sb/kg and 12mg Pb/kg in 2010 to 0.38mg Cd/kg, 0.21mg Sb/kg and 15mg Pb/kg in 2012, respectively. For the medium traffic site, the respective levels of Cd and Sb rose from 0.19mg Cd/kg and 0.14mg Sb/kg in 2010 to 0.49mg Cd/kg and 0.28mg Sb/kg in 2012. Median Pb concentrations at the medium traffic site were comparable to those at the low traffic sites (13mg/kg in 2010 and 15mg/kg in 2012). Principal Component Analysis (PCA) revealed the existence of two components (rotated), which explained 77% of the variance for all sites: 1. PC1 with large loadings of V, Cr, Co and Cu that likely originate from the commercial soil originally used for monitoring purposes, and 2. PC2 with high correlations between Cd, Sb and Pb, attributed to traffic sources of emissions. The resuspension and transport of more mobile fractions of contaminated dust and soil particles is hypothesized to be contributing to an elemental enrichment of soils located in low traffic areas.

Analysis of the antioxidant butylated hydroxytoluene (BHT) in water by means of solid phase extraction combined with GC/MS.

The antioxidant 3,5-di-tert-butyl-4-hydroxy-toluene (BHT) is widely used as an additive to increase the tenability of food and plastics. BHT is degraded to 3,5-di-tert-butyl-4-hydroxybenzaldehyde (BHT-CHO) in mammals, as well as in the natural environment such as in water and soils. BHT-CHO has been studied extensively in terms of their potential toxicities. The present investigation was carried out to quantify BHT and BHT-CHO in river, ground, rain and drinking water obtained from several locations in Germany. Apart from the compounds mentioned above, 1,2-bis-(3,5-di-tert-butyl-4-hydroxyphenyl)ethane (2-BHT), which is a dimer of BHT, was also detected in the extracts of some ground water samples. The applied analytical method is based on solid phase extraction (SPE) to concentrate trace compounds from water samples followed by gas chromatography/mass spectrometry (GC/MS) of the extracts. A total of 51 of the respective water samples were used for extraction purposes and analyte recoveries were all > or = 80%. The determination limit for BHT was 5 ng l(-1) and for BHT-CHO 16 ng l(-1). The standard deviations for the analytical procedure were 6% for BHT and 10% for BHT-CHO. The use of the antioxidant BHT in Germany has resulted in water concentrations of 7-791 ng l(-1) in the rivers Rhine, Elbe, Main, Oder, Nidda and Schwarzbach. The degradation product BHT-CHO was also detected in the river water samples at concentrations between 29 and 223 ng l(-1). The concentrations of BHT measured in German rivers are lower compared to values measured in the USA and Japan 20 years ago. In ground water, levels for BHT varied from non-detectable up to 2156 ng l(-1) and for BHT-CHO from non-detectable up to 674 ng l(-1). Both compounds were also detected in rain water in Frankfurt/Main at a concentration of 1797 ng l(-1) for BHT and 59 ng l(-1) for BHT-CHO.