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1.
Sci Total Environ ; 916: 170320, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38278278

RESUMO

In environmental analysis, the detection of water-soluble synthetic polymers (WSSP) presents considerable challenges. Thus, a precise and reproducible analytical method was developed using continuous-flow off-line pyrolysis with gas chromatography/mass spectrometry (GC/MS) to simultaneously identify multiple water-soluble polymers from a single environmental sample. WSSP are widely used in multiple industries as hydrogels due to their hydrophilic character and potential biocompatibility. This adaptability of hydrogels is reflected in their ability to provide customized formulations for specific needs, such as in the development of personal care products, medicine, and pharmaceuticals. Specifically, polyvinylpyrrolidone (PVP), poly(N-vinylcaprolactam) (PNVCL), and polyethyleneimine (PEI) were targeted for analysis in wastewater, employing unique pyrolysis products for identification. These polymers require careful assessment in wastewater to evaluate potential environmental risks associated with their release. PVP and PNVCL were identified through two pyrolysis products, while six pyrolysis products were utilized for the identification of PEI. The validated method demonstrated very good linearity and reproducibility, with correlation coefficients ranging from 0.94 to 0.99 and relative standard deviation (RSD) values between 3 % and 36 % for the targeted compounds. The limit of quantification (LOQ) for the three polymers ranged from 1 to 10 µg L-1. Moreover, the average recovery rates for these polymers, determined from artificial water samples, were approx. 85 %. Utilizing the validated method, water samples from seven wastewater treatment plants in Germany were successfully analyzed, confirming the presence of these polymers at elevated concentrations in the µg L-1 range. Notably, untreated influent waters exhibited higher polymer levels compared to treated influents and effluents, underscoring their significant contribution to overall polymer content. The developed analytical method provides an efficient tool for the simultaneous identification and quantification of PVP, PNVCL, and PEI in wastewater samples. The results highlighted the prevalent presence of PVP, PNVCL, and PEI in the tested wastewater samples, indicating their significant abundance.

2.
Environ Monit Assess ; 194(5): 385, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35445332

RESUMO

The 2011 Tohoku-oki tsunami released and mobilized many anthropogenic and natural organic compounds and, hereby, left a clear signature in its sedimentary remnants. In this study, a wide variety of organic marker substances were analyzed in 15 sediment profiles from the Aomori coast (Northern Japan). Total organic carbon (TOC) and fine grain fraction normalization have been tested with the wide dataset, and the already more frequently used TOC normalization was proven to be the more suitable one. Concentration profiles and specific ratios have been interpreted using two different approaches. Differentiation of marine and terrestrial matter characterized mixing processes due to the tsunami impact. Linking constituents to anthropogenic emission sources pointed not only to pollution revealed by the tsunami damages but also to dispersion processes, in particular erosion, transport, mixing and redeposition of particle-associated contaminants. Both approaches have been proved to identify unambiguously tsunamites in sedimentary archives and to reveal detailed insights into the tsunami-driven dispersion of particle-associated organic matter. Generally, the organic geochemical proxies as tested in this study can be reliably used to identify and characterize tsunami deposits in the sedimentary record. Finally, this strategy can be transferred to other locations affected by tsunamis for an in-depth characterization of the destruction and environmental changes induced by tsunami events.


Assuntos
Terremotos , Tsunamis , Monitoramento Ambiental , Japão
3.
Mar Pollut Bull ; 176: 113410, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35189532

RESUMO

The present-day human footprint is traceable in all environments. Growing urban centers, tourism, agricultural and industrial activities in combination with fishery, aquacultures and intense naval traffic, result in a large output of pollutants onto coastal regions. The Algarve shelf (Portugal) is one exemplary highly affected coastal system. With this study the contemporary pollution was followed in eighteen offshore surface sediment samples. Heavy metals (e.g., Cr, Pb, Cu, Hg) and organic contaminants, such as linear alkylbenzenes, dichlorodiphenyltrichloroethane metabolites, polycyclic aromatic hydrocarbons, and hopanes, have been identified and quantified, that pose hazardous effects on the marine environment and biota. This study correlates spatial distribution patterns with the pollutant composition, potential sources and pathways, each sample's grain size, and local influences, such as discharging river systems and ocean currents. This study presents a blueprint-study that allows the methodological adaption to new shelf systems with regionally different ocean current-driven distribution patterns of anthropogenic pollutants.


Assuntos
Metais Pesados , Poluentes Químicos da Água , China , Monitoramento Ambiental , Sedimentos Geológicos , Humanos , Metais Pesados/análise , Portugal , Rios , Poluentes Químicos da Água/análise
4.
J Hazard Mater ; 421: 126691, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34315022

RESUMO

While it is well recognized that the frequency and intensity of flood events are increasing worldwide, the environmental, economic, and societal consequences of remobilization and distribution of pollutants during flood events are not widely recognized. Loss of life, damage to infrastructure, and monetary cleanup costs associated with floods are important direct effects. However, there is a lack of attention towards the indirect effects of pollutants that are remobilized and redistributed during such catastrophic flood events, particularly considering the known toxic effects of substances present in flood-prone areas. The global examination of floods caused by a range of extreme events (e.g., heavy rainfall, tsunamis, extra- and tropical storms) and subsequent distribution of sediment-bound pollutants are needed to improve interdisciplinary investigations. Such examinations will aid in the remediation and management action plans necessary to tackle issues of environmental pollution from flooding. River basin-wide and coastal lowland action plans need to balance the opposing goals of flood retention, catchment conservation, and economical use of water.


Assuntos
Poluentes Ambientais , Inundações , Saúde Ambiental , Humanos , Rios
5.
Environ Earth Sci ; 80(8): 314, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33850569

RESUMO

The present editorial 2020 continues the series of status reports in Environmental Earth Sciences (EES) in previous years 2017 and 2019 (Kolditz et al. in Environ Earth Sci 77: 8, 2018, Kolditz et al. in Environ Earth Sci 79: 11, 2020). The year 2020 coming to an end was heavily influenced by the COVID-19 pandemic affecting all areas of life including research work and, therefore, scientific publishing as well ("Introduction"). One bright spot which shows longevity of journals that produce a quality product is that Environmental Earth Sciences (EES) is celebrating its 45th anniversary of publication. To this extent EES continues the tradition to honor the most cited papers contributing to the 2020 Impact Factor (IF) ("Highly and most cited topics") and provide information on the current status of EES as well as an outlook to 2021 ("Progress report").

6.
Sci Rep ; 11(1): 8947, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33903640

RESUMO

With a minimum of three reported waves, the 2011 Tohoku-oki tsunami's destructive force caused massive damage along the northern Japanese Aomori coast. At Misawa the coastal control area was inundated up to 550 m inland and sandy sediment remnants can be traced to c. 350 m (c. 61-63% of the maximum inundation) from the shoreline. Linking the discovery of floatable plastic objects within a woody and organic layer to our analytical data lead to the detection of a yet undocumented woody-organic tsunami deposit first appearing on top of the sandy deposit but then reaching even further inland (approx. 69-72% of the max. inundation). By this observation our understanding of the documented part of the tsunami inundation may be improved. As a consequence, sand sheets of historic and paleo-tsunamis represent minimum estimates for the coastal inundation and underestimation may be reduced by addressing the woody and organic fraction of a tsunami's inundation.

7.
Water Sci Technol ; 83(3): 532-542, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33600359

RESUMO

The tremendous increase of plastic production, its intensive usage in packaging, as transport material, and the insufficient management of plastic garbage have led to a rise in microplastic particles as an anthropogenic contaminant in our environment. To develop appropriate management and remediation strategies for this global pollution problem, reliable and consistent analytical procedures for measuring plastics in the complex matrices need to be designed. The applicability of an easy, robust and fast multi-step approach was tested on three sediment samples from riverine, beach and backwater areas of varying origin, grain size and organic matter content, and is reported here. The optimized method included grain size fractionation, density separation and µ-FTIR analyses. Identification was based on two complementary methods of µ -FTIR measurements, the Image mode for small microplastics (<1 mm) and the ATR method for bigger (1-5 mm) particles. The analyses revealed the identification of several polymers in various grain sizes at different pollution levels. Major findings are the dominance of PET particles and the highest frequency of microplastic particles in the midsize fraction of 100-500 µm. Generally, the method was able to reliably detect microplastic particles in several grain size fractions and down to very low contamination levels of approximately. ten particles per 50 g of sediments with different organic matter content and various grain size characteristics. Moreover, the presented multi-step approach represents a fast, easy and less cost-effective method as an alternative to more expensive and time-consuming methods.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Poluição Ambiental , Sedimentos Geológicos , Plásticos , Poluentes Químicos da Água/análise
8.
Sci Total Environ ; 761: 143230, 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33158517

RESUMO

Per- and polyfluoroalkyl substances (PFAS) are persistent and toxic contaminants that are ubiquitous in the environment. They can incorporate into soil as nonextractable residues (NER) which are not detectable with conventional analytical protocols but are still possible to remobilize with changes of surrounding conditions, and thus will be bioavailable again. Therefore, there is a need to investigate thoroughly the long-term fate of NER-PFAS. In this study, a 240-day incubation of perfluorooctanesulfonate (PFOS) and its alternative 6:2 chlorinated polyfluorinated ether sulfonate (F-53B) in a silty clay topsoil was carried out. Solvent extraction, alkaline hydrolysis and sequential chemical degradation were applied on periodically sampled soil to obtain extractable, moderately bound and deeply bound PFAS, respectively. The results confirmed the formation of NER of both compounds but with different preferences of incorporating mechanisms. NER-PFOS was formed predominantly by covalent binding (via head group) and strong adsorption (via tail group). The formation of NER-F-53B was mainly driven by physical entrapment. Both bound compounds within the incubation period showed three-stage behaviors including an initial period with slight release followed by a (re) incorporating stage and a subsequent remobilizing stage. This work provides some first insights on the long-term dynamic behaviors of nonextractable PFAS and will be conducive to their risk assessment and remediation (e.g. estimating potential NER-PFAS level based on their free extractable level, and selecting remediation methods according to their prevailing binding mechanisms).

9.
Water Sci Technol ; 81(4): 834-844, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32460286

RESUMO

Microplastic particles have been recognized as global hazardous pollutants in the last few decades pointing to the importance of analyzing and monitoring microplastics, especially in soils and sediments. This study focused on a multi-step approach for microplastic analysis combining grain size fractionation, density separation and identification by µ-FTIR-spectroscopy. Eight widely used polymers (polyethylene (PE), polypropylene (PP), polyvinylchloride (PVC), polystyrol (PS), polyethylenterephthalate (PET), polymethylmethacrylate (PMMA), polyurethane (PU) and polyamide (PA)) were fractionated into four groups of grain sizes (0.1-5 mm). Thereafter, sea sand was spiked with these particles to test a ZnCl2-based density separation for the polymer types and the various grain sizes. The obtained recovery rates were close to 100% showing that ZnCl2-based density separation is suitable to separate the polymer particles from a sandy matrix. This approach was extended on three further environmental matrices and recovery rates for two of them (sandy-silty and fine-grained sediment) also provided reliable values (94-106%). Lastly, the developed multi-step approach was verified by analyzing an environmental sample (sediment from river Tiranë, Albania) characterized by smaller grain size and moderate organic matter content. Identification of two polymer types in different grain size classes verified the suitability of the developed approach for microplastic analyses on particulate matter such as soils and sediments.


Assuntos
Plásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Microplásticos , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Environ Geochem Health ; 42(2): 693-707, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31446575

RESUMO

The objective of this study is geochronological investigation of sedimentological and inorganic composition, in the Danube Djerdap Lake sediments in order to obtain reliable information about former pollution. Eleven samples were taken from the 135-cm-deep sediment core drilled at the Orlova location. Since the core represents sediments deposited during 1972-2016, the sedimentation rate of ~ 3 cm year-1 was estimated. Grain size, mineralogical and geochemical composition was determined. Sediments are sandy silts and clayey silts, and only the deepest and shallowest layers contain > 30% of sand-size fraction. The highest concentrations of minor elements are found in the oldest sediment (1972-1977) as a consequence of the high flux of the material from variable sources. During the sedimentation period (1975-1990), the concentrations of analyzed elements are generally decreasing until the beginning of 1990s. After this period, there are two distinct decreases and two distinct increases in concentrations of elements. The fluctuations in minor element concentrations are a consequence of both natural and anthropogenic sources. Granitic rocks situated south are source of minerals that carry minor elements. Enrichment Factor, Geoaccumulation Index, Contamination Factor and Pollution Load Index indicate that concentrations of certain minor elements at specific depositional periods have anthropogenic source.


Assuntos
Sedimentos Geológicos/química , Lagos/química , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Sedimentos Geológicos/análise , Hidrologia/métodos , Lagos/análise , Metais/análise , Minerais/análise , Sérvia
11.
J Hazard Mater ; 381: 120959, 2020 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-31401459

RESUMO

Anthropogenic organohalogens (AOHs) are toxic and persistent pollutants that occur ubiquitously in the environment. An unneglectable portion of them can convert into nonextractable residues (NER) in the natural solid substances. NER-AOHs are not detectable by conventional solvent-extraction, and will get remobilized through changes of surrounding environment. Consequently, the formation and fate of NER-AOHs should be investigated comprehensively. In this study, solvent extraction, sequential chemical degradation and thermochemolysis were applied on different sample matrices (sediments, soils and groundwater sludge, collected from industrial areas) to release extractable and nonextractable AOHs. Covalent linkages were observed most favorable for the hydrophilic-group-containing monocyclic aromatic AOHs (HiMcAr-AOHs) (e.g. halogenated phenols, benzoic acids and anilines) incorporating into the natural organic matter (NOM) as NER. Physical entrapment mainly contributed to the NER formation of hydrophobic monocyclic aromatic AOHs (HoMcAr-AOHs) and polycyclic aromatic AOHs (PcAr-AOHs). The hypothesized remobilization potential of these NER-AOHs follow the order HiMcAr-AOHs > HoMcAr-AOHs/ aliphatic AOHs > PcAr-AOHs. In addition, the NOM macromolecular structures of the studied samples were analyzed. Based on the derived results, a conceptual model of the formation mechanisms of NER-AOHs is proposed. This model provides basic molecular insights that are of high value for risk assessment and remediation of AOHs.

12.
Chemosphere ; 243: 125284, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31759210

RESUMO

In order to recognize organic contaminants responsible for ecological stresses from intensive shipping traffic and dockyard works, this study aimed at characterizing the sediment contamination of a large industrialized port located in Hainan Island, China. Surface sediment samples were collected from 17 stations including the main docks, the dockyards and the major industrial wastewater outlets. Organotin compounds, the pesticide DDT (bis(chlorophenyl)trichloroethane) and its metabolites and polycyclic aromatic compounds were identified as main pollutant groups by GC/MS applying a non-target screening approach. The pesticide DDT and its metabolites were found in the same samples as the organotin derivatives pointing to similar emission sources. The concurrent presence of these compounds in the dockyard samples suggests a combined usage of organotin compounds and DDT as active ingredients in antifouling paints in Yangpu. As highly specific molecular indicators for dockyard activities, butyltin and phenyltin compounds were identified. Noteworthy, also tributylmethyltin and triphenylmethyltin were detected, likely resulting from microbial assisted biomethylation of synthetic organotin compounds in the sediments. The concentrations of PAHs, DDX and TBT in sediments from dockyards exceeded global sediment quality guidelines and the toxicity thresholds, and potentially have adverse biological effects on marine organisms.


Assuntos
Diclorodifenil Dicloroetileno/análise , Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , China , Sedimentos Geológicos , Desenvolvimento Industrial , Compostos Orgânicos de Estanho/análise , Navios , Estanho/análise
13.
Environ Sci Technol ; 53(3): 1305-1314, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30608655

RESUMO

Nonextractable residues (NER) are pollutants incorporated into the matrix of natural solid matter via different binding mechanisms. They can become bioavailable or remobilize during physical-chemical changes of the surrounding conditions and should thus not be neglected in environmental risk assessment. Sediments, soils, and groundwater sludge contaminated with DDXs (DDT, dichlorodiphenyltrichloroethane; and its metabolites) were treated with solvent extraction, sequential chemical degradation, and thermochemolysis to study the fate of NER-DDX along different environmental aquatic-terrestrial pathways. The results showed that DDT and its first degradation products, DDD (dichlorodiphenyldichloroethane) and DDE (dichlorodiphenyldichloroethylene), were dominant in the free extractable fraction, whereas DDM (dichlorodiphenylmethane), DBP (dichlorobenzophenone), and DDA (dichlorodiphenylacetic acid) were observed primarily after chemical degradation. The detection of DDA, DDMUBr (bis( p-chlorophenyl)-bromoethylene), DDPU (bis( p-chlorophenyl)-propene) and DDPS (bis( p-chlorophenyl)-propane) after chemical treatments evidenced the covalent bindings between these DDXs and the organic matrix. The identified NER-DDXs were categorized into three groups according to the three-step degradation process of DDT. Their distribution along the different pathways demonstrated significant specificity. Based on the obtained results, a conceptual model of the fate of NER-DDXs on their different environmental aquatic-terrestrial pathways is proposed. This model provides basic knowledge for risk assessment and remediation of both extractable and nonextractable DDT-related contaminations.


Assuntos
DDT , Sedimentos Geológicos , Diclorodifenil Dicloroetileno , Diclorodifenildicloroetano , Monitoramento Ambiental
14.
J Hazard Mater ; 353: 360-371, 2018 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-29684888

RESUMO

The pesticide DDT (1-chloro-4-[2,2,2-trichloro-1-(4-chlorophenyl)ethyl]benzene) and its degradates are among the most persistent and abundant organochlorine contaminates in the environment, and DDT is still being produced in several Asian countries. In this study, we report for the first time on the detection of DDT-related compounds with one additional or missing chlorine atom at the phenyl group (DDX±Cl) in sediment and soil samples taken in the vicinity of former and current DDT production sites. These congeneric compounds most likely originate from production residues disposed of into the environment. In order to ensure an adequate identification and quantification of this novel organic pollutant group, individual DDX±Cl were synthesized as reference compounds by simulating an impure production of DDT in the laboratory. In contrast to DDX±Cl with (chloro)alkyl moieties, DDX±Cl with (chloro)alkenyl moieties cannot be unambiguous assigned by gas-chromatographic/mass spectrometric (GC/MS) fragmentation and elution orders. The occurrence of DDX±Cl in environmental samples allows to draw conclusions about the purity of the production process in the associated production sites. Moreover, they potentially can serve as molecular indicators to differentiate between industrial DDT emissions and insecticidal applications of DDT. This hypothesis has yet to be confirmed by further research.

15.
Environ Sci Pollut Res Int ; 24(35): 27539-27552, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28929288

RESUMO

During the last decades, the global industrial production partly shifted from industrialized nations to emerging and developing countries. In these upcoming economies, the newly developed industrial centers are generally located in densely populated areas, resulting in the discharge of often only partially treated industrial and municipal wastewaters into the surface waters. There is a huge gap of knowledge about the composition of the complex organic pollutant mixtures occurring in such heavily impacted areas. Therefore, we applied a non-target screening to comprehensively assess river pollution in a large industrial area located in the megacity Jakarta. More than 100 structurally diverse organic contaminants were identified, some of which were reported here for the first time as environmental contaminants. The concentrations of paper manufacturing chemicals in river water-for example, of the endocrine-disrupting compound bisphenol A (50-8000 ng L-1)-were as high as in pure untreated paper industry wastewaters. The non-target screening approach is the adequate tool for the identification of water contaminants in the new global centers of industrial manufacturing-as the first crucial step towards the evaluation of as yet unrecognized environmental risks.


Assuntos
Compostos Benzidrílicos/análise , Disruptores Endócrinos/análise , Monitoramento Ambiental/métodos , Fenóis/análise , Rios/química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Desenvolvimento Econômico , Indonésia , Indústrias , Urbanização
16.
Water Sci Technol ; 76(3-4): 832-846, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28799930

RESUMO

There is a lack of knowledge in environmental pollution of the anthropogenic contaminants in wastewater and surface water. Several organic compounds merit special attention, because of their potential risk to the aquatic environment. Therefore, gas chromatography-mass spectrometry-based screening analyses were performed in order to identify anthropogenic organic contaminants and to reveal information on the structural diversity of individual compounds and to characterize their environmental behavior. Wastewater samples from wastewater treatment plants in Germany, representing various capacities, and surface water samples from corresponding receiving waters were analyzed. Numerous substances were identified in the samples. Several compounds were treated inadequately during wastewater treatment, and their identification in surface waters highlights their potential impact on the aquatic environment. Contaminants were selected according to available information about their environmental relevance (e.g. persistence, bioaccumulation potential), their possible application or usage and their occurrence within the environment. Based on the results of this study, it is recommended that non-target screening analyses be undertaken to identify the structural diversity of anthropogenic organic contaminants and that further investigations of specific anthropogenic compounds be undertaken as a high priority.


Assuntos
Monitoramento Ambiental , Compostos Orgânicos/química , Águas Residuárias/química , Poluentes Químicos da Água/química , Alemanha , Eliminação de Resíduos Líquidos
17.
Environ Sci Eur ; 29(1): 23, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28752018

RESUMO

Protecting our water resources in terms of quality and quantity is considered one of the big challenges of the twenty-first century, which requires global and multidisciplinary solutions. A specific threat to water resources, in particular, is the increased occurrence and frequency of flood events due to climate change which has significant environmental and socioeconomic impacts. In addition to climate change, flooding (or subsequent erosion and run-off) may be exacerbated by, or result from, land use activities, obstruction of waterways, or urbanization of floodplains, as well as mining and other anthropogenic activities that alter natural flow regimes. Climate change and other anthropogenic induced flood events threaten the quantity of water as well as the quality of ecosystems and associated aquatic life. The quality of water can be significantly reduced through the unintentional distribution of pollutants, damage of infrastructure, and distribution of sediments and suspended materials during flood events. To understand and predict how flood events and associated distribution of pollutants may impact ecosystem and human health, as well as infrastructure, large-scale interdisciplinary collaborative efforts are required, which involve ecotoxicologists, hydrologists, chemists, geoscientists, water engineers, and socioeconomists. The research network "project house water" consists of a number of experts from a wide range of disciplines and was established to improve our current understanding of flood events and associated societal and environmental impacts. The concept of project house and similar seed fund and boost fund projects was established by the RWTH Aachen University within the framework of the German excellence initiative with support of the German research foundation (DFG) to promote and fund interdisciplinary research projects and provide a platform for scientists to collaborate on innovative, challenging research. Project house water consists of six proof-of-concept studies in very diverse and interdisciplinary areas of research (ecotoxicology, water, and chemical process engineering, geography, sociology, economy). The goal is to promote and foster high-quality research in the areas of water research and flood-risk assessments that combine and build off-laboratory experiments with modeling, monitoring, and surveys, as well as the use of applied methods and techniques across a variety of disciplines.

18.
J Environ Sci Health B ; 52(8): 584-599, 2017 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-28494222

RESUMO

The incorporation of xenobiotics into soil, especially via covalent bonds or sequestration has a major influence on the environmental behavior including toxicity, mobility, and bioavailability. The incorporation mode of 4-chloro-2-methylphenoxyacetic acid (MCPA) into organo-clay complexes has been investigated under a low (8.5 mg MCPA/kg soil) and high (1000 mg MCPA/kg soil) applied concentration, during an incubation period of up to 120 days. Emphasis was laid on the elucidation of distinct covalent linkages between non-extractable MCPA residues and humic sub-fractions (humic acids, fulvic acids, and humin). The cleavage of compounds by a sequential chemical degradation procedure (OH-, BBr3, RuO4, TMAH thermochemolysis) revealed for both concentration levels ester/amide bonds as the predominate incorporation modes followed by ether linkages. A possible influence of the soil microbial activity on the mode of incorporation could be observed in case of the high level samples. Structure elucidation identified MCPA as the only nonextractable substance, whereas the metabolite 4-chloro-2-methylphenol was additionally found as bioavailable and bioaccessible compound.


Assuntos
Ácido 2-Metil-4-clorofenoxiacético/química , Poluentes do Solo/química , Ácido 2-Metil-4-clorofenoxiacético/metabolismo , Silicatos de Alumínio/química , Benzopiranos/química , Biodegradação Ambiental , Argila , Cresóis/química , Alemanha , Herbicidas/química , Herbicidas/metabolismo , Substâncias Húmicas , Solo/química , Microbiologia do Solo , Poluentes do Solo/metabolismo
19.
Int J Hyg Environ Health ; 220(2 Pt B): 440-444, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28034615

RESUMO

For decades, plasticizers have been produced in high quantities to improve the flexibility and durability of products. One possible replacement product is alkylsulfonic acid phenylesters (ASEs), marketed as Mesamoll®. This study aimed to quantify the ASE dust contamination of residences and daycare centers to obtain insight into the recent exposure situation. ASEs were quantified in dust samples collected from 25 residences and 25 daycare centers using GC/MS measurements. Median (95th percentile) values of the sum of tetra- to heptadecylphenylesters are higher in daycare centers, with a value of 19.6mg/kg (216mg/kg), compared to residences, with a value of 7.6mg/kg (171mg/kg). A daily non-dietary intake of 0.08 and 0.86µg/kg b.w., respectively, was observed using the median and 95th percentile values obtained from dust samples. These levels are 1250 and 115 times below a previously set temporary tolerable daily intake value. Nevertheless, the fact that basic data on toxicity and exposure via other pathways are limited or unavailable at present has to be considered.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Poeira/análise , Plastificantes/análise , Ácidos Sulfônicos/análise , Criança , Creches , Monitoramento Ambiental , Ésteres/análise , Alemanha , Habitação , Humanos
20.
Environ Sci Pollut Res Int ; 23(21): 21894-21907, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27530197

RESUMO

The main objective of this study was the development of simple multi-parameter methods for the analyses of biocides in various environmental matrices (wastewater, surface water, and sewage sludge) for measurement and monitoring activities. Eight target substances (triclosan, methyltriclosan (transformation product of triclosan), cybutryne (Irgarol), and the azole fungicides propiconazole, tebuconazole, imazalil, thiabendazole, and cyproconazole) were chosen for determination in selected sample sets. For surface water and wastewater samples a solid-phase extraction (SPE) method and for sewage sludge samples an accelerated solvent extraction (ASE) were developed. The extracts were analyzed by gas chromatographic-mass spectrometric methods (GC/MS), and the analytical methods were checked to ensure sufficient sensitivity by comparing the limits of quantification (LOQs) to the predicted no effect concentrations (PNECs) of the selected biocides. For quality control, recovery rates were determined. Finally, developed methods were checked and validated by application on sample material from various matrices. Sampling took place in seven urban wastewater treatment plants and their corresponding receiving waters. The results revealed that the developed extraction methods are effective and simple and allow the determination of a broad range of biocides in various environmental compartments.


Assuntos
Monitoramento Ambiental/métodos , Praguicidas/química , Poluentes Químicos da Água/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Esgotos/química , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Águas Residuárias/análise , Água/química
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