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1.
Sci Total Environ ; 806(Pt 4): 150701, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34634353

RESUMO

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.


Assuntos
Água Potável , Água Subterrânea , Poluentes Químicos da Água , Dioxanos/análise , Alemanha , Poluentes Químicos da Água/análise
2.
Sci Total Environ ; 711: 134783, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31818603

RESUMO

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.


Assuntos
Água Potável/química , Dioxanos , Alemanha , Água Subterrânea , Poluentes Químicos da Água
3.
BMC Chem ; 13(1): 70, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31384817

RESUMO

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.

4.
Environ Pollut ; 245: 343-352, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30448504

RESUMO

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.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Materiais de Construção/análise , Poeira/análise , Monitoramento Ambiental/métodos , Retardadores de Chama/análise , Organofosfatos/análise , Alemanha , Humanos , Tamanho da Partícula
5.
Sci Total Environ ; 619-620: 712-720, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29166627

RESUMO

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.

6.
Environ Sci Pollut Res Int ; 24(12): 10992-11005, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27230144

RESUMO

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.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Retardadores de Chama/análise , Organofosfatos/análise , Poeira , Alemanha
7.
Sci Total Environ ; 538: 564-72, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26318809

RESUMO

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.


Assuntos
Monitoramento Ambiental , Metaloides/análise , Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Cidades , Ontário , Análise de Componente Principal
8.
Geochem Trans ; 16: 2, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25949212

RESUMO

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.

9.
J Appl Toxicol ; 35(11): 1254-61, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25988240

RESUMO

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.


Assuntos
Disruptores Endócrinos/análise , Equipamentos para Lactente , Plásticos/química , Antagonistas de Androgênios/análise , Bioensaio , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Lactente , Parabenos/análise
10.
Sci Total Environ ; 497-498: 634-641, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25170829

RESUMO

In a former study, a German lignite extract exhibited toxicity to Danio rerio and Caenorhabditis elegans and was shown to have mutagenic and dioxin-like activity. Besides the comparatively low content of known toxic polycyclic aromatic hydrocarbons (PAH), highly intensive peaks of m/z 274 and m/z 324 were observed during the chromatographic analysis. These compounds are assumed to be alkylated chrysenes and picenes (3,3,7-trimethyl-1,2,3,4-tetrahydrochrysene, 1,2-(1'-isopropylpropano)-7-methylchrysene and an isomer of the latter, 1,2,9-trimethyl-1,2,3,4-tetrahydropicene and 2,2,9-trimethyl-1,2,3,4-tetrahydropicene). These compounds are intermediates in the diagenetic formation of chrysene and picene from triterpenoids. Due to their general high abundance in lignites and the toxicity observed for the lignite extract, the mechanism-specific toxicity and bioavailability of these compounds were investigated in the present study using the approach of effect-directed analysis. After the separation of the compounds from other PAH, their mutagenic activity (Ames Fluctuation test) and dioxin-like activity (EROD activity) were studied. Both, mutation induction factor (up to 2.9±2.7) and dioxin-like activity (Bio-TEQ of 224±75 pg/g; represents the amount (pg) 2,3,7,8-tetrachlorodibenzo-p-dioxin per g coal that would provoke the same toxic effect) were rather low. Bioavailability estimated by the bioaccumulation test with Lumbriculus variegatus was also very limited. Based on the obtained results, the environmental risk of the highly abundant alkylated chrysenes and picenes in lignites is concluded to be low.


Assuntos
Crisenos/toxicidade , Dioxinas/toxicidade , Mutagênicos/toxicidade , Alquilação , Carvão Mineral/toxicidade
11.
Sci Total Environ ; 494-495: 320-8, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25063955

RESUMO

Investigations of the bioavailability and toxicity of polycyclic aromatic compounds (PAC) have rarely considered the heterogeneity of coals and the impact of more polar PAC besides polycyclic aromatic hydrocarbons (PAH). Earlier, we investigated the toxicity of eight heterogeneous coals and their extracts. In the present study, the hazard potential with respect to mechanism-specific toxicity of polar fractions of dichloromethane extracts from coals was studied. Polar extract fractions of all coal types except for anthracite induced EROD activity (determined in RTL-W1 cells), independent of coal type (Bio-TEQs between 23 ± 16 and 52 ± 22 ng/g). The polar fractions of all bituminous coal extracts revealed mutagenic activity (determined using the Ames Fluctuation test). No significant mutation induction was detected for the polar extract fractions from the lignite, sub-bituminous coal and anthracite samples, which indicates a higher dependency on coal type for polar PAC here. Additionally, information on bioavailability was derived from a bioaccumulation test using the deposit-feeding oligochaete Lumbriculus variegatus which was exposed for 28 days to ground coal samples. Despite the high toxic potential of most coal extracts and a reduced biomass of Lumbriculus in bituminous coal samples, bioaccumulation of PAH and mortality after 28 days were found to be low. Limited bioaccumulation of PAH (up to 3.6 ± 3.8 mg/kg EPA-PAH) and polar PAC were observed for all coal samples. A significant reduction of Lumbriculus biomass was observed in the treatments containing bituminous coals (from 0.019 ± 0.004 g to 0.046 ± 0.011 g compared to 0.080 ± 0.025 g per replicate in control treatments). We conclude that bioavailability of native PAC from coals including polar PAC is low for all investigated coal types. In comparison to lignite, sub-bituminous coals and anthracite, the bioavailability of PAC from bituminous coals is slightly increased.


Assuntos
Carvão Mineral/toxicidade , Citocromo P-450 CYP1A1/metabolismo , Mutagênicos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Carvão Mineral/análise , Indução Enzimática/efeitos dos fármacos , Mutagênicos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise
12.
Anal Bioanal Chem ; 406(11): 2495-502, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24604322

RESUMO

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.


Assuntos
Clorófitas/química , Espectrometria de Massas/métodos , Microalgas/química , Nanopartículas/análise , Titânio/análise , Verduras/química , Clorófitas/metabolismo , Espectrometria de Massas/normas , Microalgas/metabolismo , Nanopartículas/metabolismo , Padrões de Referência , Titânio/metabolismo , Verduras/metabolismo
13.
Water Res ; 48: 406-19, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24200013

RESUMO

Potential health effects of 1,4-dioxane and the limited data on its occurrence in the water cycle command for more research. In the current study, mobility and persistence of 1,4-dioxane in the sewage-, surface-, and drinking water was investigated. The occurrence of 1,4-dioxane was determined in wastewater samples from four domestic sewage treatment plants (STP). The influent and effluent samples were collected during weekly campaigns. The average influent concentrations in all four plants ranged from 262 ± 32 ng L(-1) to 834 ± 480 ng L(-1), whereas the average effluent concentrations were between 267 ± 35 ng L(-1) and 62,260 ± 36,000 ng L(-1). No removal of 1,4-dioxane during water treatment was observed. Owing to its strong internal chemical bonding, 1,4-dioxane is considered non-biodegradable under conventional bio-treatment technologies. The source of increased 1,4-dioxane concentrations in the effluents was identified to originate from impurities in the methanol used in the postanoxic denitrification process in one of the STPs. In view of poor biodegradation in STPs, surface water samples were collected to establish an extent of 1,4-dioxane pollution. Spatial and temporal distribution of 1,4-dioxane in the Rivers Main, Rhine, and Oder was examined. Concentrations reaching 2200 ng L(-1) in the Oder River, and 860 ng L(-1) in both Main and Rhine River were detected. The average monthly load of 1,4-dioxane in the Rhine River was calculated to equal to 172 kg d(-1). In all rivers, concentration of 1,4-dioxane increased with distance from the spring and was found to negatively correlate with the discharge of the river. Additionally, bank filtration and drinking water samples from two drinking water facilities were analyzed for the presence of 1,4-dioxane. The raw water contained 650 ng L(-1)-670 ng L(-1) of 1,4-dioxane, whereas the concentration in the drinking water fell only to 600 ng L(-1) and 490 ng L(-1), respectively. Neither of the purification processes employed was able to reduce the presence of 1,4-dioxane below the precautionary guideline limit of 100 ng L(-1) set by the German Federal Environmental Agency.


Assuntos
Dioxanos/química , Água Potável , Esgotos , Poluentes Químicos da Água/química
14.
Environ Sci Pollut Res Int ; 21(2): 1572-81, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23943080

RESUMO

The purpose of this study is to examine tissue patterns of metal (Cr, Ni, Cu, Cd, and Pb) concentrations in Solanum melongena cultivated in close proximity to traffic to help elucidate associated elemental deposition and soil-to-root and root-to-shoot transfers. Plants were cultivated in a commercial soil mix at three sites in Toronto, Canada. Metal concentrations were determined on microwave-digested bulk and rhizosphere soil and tissue samples per ICP-MS, along with two standard reference materials (NIST #1570a and #2709a). Unwashed and washed S. melongena samples were also analyzed, along with Origanum vulgare plants from the same sites, to assess the effectiveness of washing in reducing metal concentrations. The tissue distribution of Cr, Ni, Cu, and Pb demonstrated variability as a function of traffic proximity. Copper was found to easily translocate to roots in soils susceptible to waterlogging, while Cd had the highest soil-to-root and root-to-shoot translocation. The translocation of Cd was highest at the roadside site, due to a greater relative enrichment of this metal in the rhizosphere of S. melongena plants. Washing O. vulgare leaves was more effective in removing metal-associated particles compared to S. melongena samples. Cadmium uptake is of greatest concern given its toxicity and translocation potential.


Assuntos
Metais/análise , Modelos Químicos , Poluentes do Solo/análise , Solanum melongena/fisiologia , Canadá , Metais/metabolismo , Raízes de Plantas , Rizosfera , Solo/química , Poluentes do Solo/metabolismo
15.
Sci Total Environ ; 468-469: 671-6, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24061058

RESUMO

2,4,7,9-Tetramethyl-5-decyne-4,7-diol (TMDD) is a non-ionic surfactant which is preferentially used as defoamer in paints and printing ink and for the treatment of surfaces. Effluents of wastewater treatment plants (WWTPs) have been identified as the domination point sources for TMDD in rivers since the removal rate of the compound in the WWTPs is in general less than 70%. However, the dominating entry pathways of TMDD into the sewage were unknown so far. In this study effluents from both, municipal WWTPs with and without treatment of indirect industrial dischargers and from industrial WWTPs with direct discharge of wastewater into receiving rivers were analyzed for the first time to identify the proportions of TMDD coming from domestic wastewater and from various industrial sources. Moreover, rivers were samples before and after the influent of sewage water from WWTPs. The TMDD concentrations in the water samples were measured using solid phase extraction (SPE) followed by gas chromatography/mass spectrometry (GC/MS). High TMDD concentrations were found in rivers (up to 63.5 µg/L), and in effluents of WWTPs (up to 310 µg/L) affected by wastewater from paper recycling industry and factories producing paint and printing ink. Concentrations of TMDD revealed to be far higher in wastewater from factories processing recycled paper (up to 113 µg/L) compared to wastewater from factories not processing recycled paper (0.066 µg/L). The results indicate that the use of recycling paper in the paper production process is the dominating reason for increased TMDD concentrations in wastewaters and receiving rivers due to the wash out of TMDD from the paper impregnated with printing ink. Very high TMDD concentrations (up to 3300 µg/L) were also detected in wastewater from a printing ink factory and a paint factory.


Assuntos
Álcoois Graxos/análise , Tinta , Papel , Rios/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/análise , Cromatografia Gasosa-Espectrometria de Massas , Alemanha , Reciclagem/métodos , Extração em Fase Sólida
16.
Environ Sci Technol ; 47(20): 11766-75, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24024738

RESUMO

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.


Assuntos
Carvão Mineral/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Testes de Toxicidade Aguda , Poluentes Químicos da Água/toxicidade , Animais , Bioensaio , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/embriologia , Embrião não Mamífero/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Peixe-Zebra/embriologia
17.
Chemosphere ; 90(6): 1952-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23159069

RESUMO

The photodegradation and biotic transformation of the pharmaceuticals lidocaine (LDC), tramadol (TRA) and venlafaxine (VEN), and of the metabolites O-desmethyltramadol (ODT) and O-desmethylvenlafaxine (ODV) in the aquatic environmental have been investigated. Photodegradation experiments were carried out using a medium pressure Hg lamp (laboratory experiments) and natural sunlight (field experiments). Degradation of the target compounds followed a first-order kinetic model. Rates of direct photodegradation (light absorption by the compounds itself) at pH 6.9 were very low for all of the target analytes (≤0.0059 h(-1) using a Hg lamp and ≤0.0027 h(-1) using natural sunlight), while rates of indirect photodegradation (degradation of the compounds through photosensitizers) in river water at pH 7.5 were approximately 59 (LDC), 5 (TRA), 8 (VEN), 15 (ODT) and 13 times (ODV) higher than the rates obtained from the experiments in ultrapure water. The accelerated photodegradation of the target compounds in natural water is attributed mainly to the formation of hydroxyl radicals through photochemical reactions. Biotic (microbial) degradation of the target compounds in surface water has been shown to occur at very low rates (≤0.00029 h(-1)). The half-life times determined from the field experiments were 31 (LDC), 73 (TRA), 51 (VEN), 21 (ODT) and 18h (ODV) considering all possible mechanisms of degradation for the target compounds in river water (direct photodegradation, indirect photodegradation and biotic degradation).


Assuntos
Cicloexanóis/química , Lidocaína/química , Rios/química , Tramadol/química , Poluentes Químicos da Água/química , Succinato de Desvenlafaxina , Concentração de Íons de Hidrogênio , Modelos Químicos , Processos Fotoquímicos , Luz Solar , Tramadol/análogos & derivados , Cloridrato de Venlafaxina
18.
Sci Total Environ ; 442: 86-95, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23178768

RESUMO

This research examines traffic-related trace element emissions and their uptake by plants grown in urban roadside environments in Toronto, Canada. Oregano (Origanum vulgare), beets (Beta vulgaris) and eggplants (Solanum melongena) were cultivated at four locations with variable traffic-related metal inputs in 2010. The top 30 cm of soil at the medium-traffic location was first replaced with a triple mix soil (topsoil, compost and peat) to control for pre-existing contamination. The same soil was used to cultivate at the two no/low traffic locations. Soil at the heavy traffic location was not remediated. Soil, plant tissue and plant rhizosphere samples were collected for the analysis of a range of traffic-related metal(loids) using ICP-MS, including Cr, Mn, Cu, Ni, Cd, As, Sb and Pb. Samples were digested with HNO(3) and HCl using a microwave-assisted digestion procedure and then treated with HF prior to analysis. Two certified reference materials, San Joaquin soil (NIST 2709a) and trace elements in spinach leaves (NIST 1570a), were used for QA/QC purposes. Metal(loid) concentrations and accumulation over time were highly variable at the medium traffic site where the soil was replaced. Mn (p<0.10), As (p<0.10) and Sb (p<0.01) concentrations significantly increased in bulk soils from May to November 2010, while Ce (p<0.01) and Cd (p<0.10) levels decreased. For instance, median As concentrations increased from 4.39 to 8.40 mg/kg over this period. Metals were found to be more bioaccessible to O. vulgare grown in the new soil at the medium traffic volume site, compared to the aged soil at the heavy traffic location. Several elements, most notably Cd, were also found to accumulate in the root zone of sampled S. melongena. Metal concentrations in S. melongena rhizosphere were better predictors of plant tissue levels, providing evidence that soil quality guidelines based on total metal concentrations for bulk soils are inadequate.


Assuntos
Monitoramento Ambiental/métodos , Metais Pesados/análise , Plantas Comestíveis/crescimento & desenvolvimento , Poluentes do Solo/análise , Oligoelementos/análise , Emissões de Veículos/análise , Beta vulgaris/crescimento & desenvolvimento , Beta vulgaris/metabolismo , Cidades , Metais Pesados/metabolismo , Ontário , Origanum/crescimento & desenvolvimento , Origanum/metabolismo , Plantas Comestíveis/metabolismo , Rizosfera , Estações do Ano , Poluentes do Solo/metabolismo , Solanum melongena/crescimento & desenvolvimento , Solanum melongena/metabolismo , Oligoelementos/metabolismo
19.
Environ Sci Technol ; 46(18): 10326-33, 2012 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-22913340

RESUMO

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.


Assuntos
Pulmão/metabolismo , Paládio/metabolismo , Material Particulado/metabolismo , Platina/metabolismo , Ródio/metabolismo , Humanos , Líquido Intracelular/metabolismo , Lisossomos/metabolismo , Paládio/análise , Material Particulado/análise , Platina/análise , Ródio/análise
20.
J Environ Monit ; 14(5): 1391-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22446514

RESUMO

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

Assuntos
Cicloexanóis/análise , Água Subterrânea/química , Lidocaína/análise , Tramadol/análise , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/análise , Succinato de Desvenlafaxina , Monitoramento Ambiental , Rios/química , Tramadol/análogos & derivados , Cloridrato de Venlafaxina , Poluição Química da Água/estatística & dados numéricos
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