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1.

Background, aim, and scope  

As possible precursors of PFOA, fluorotelomer alcohols are a class of highly fluorinated and volatile compounds. Although they are widespread in the environment, little toxicity data is available. The present study focused on testing the population growth impairment potential of FTOH. Moreover, certain efforts were made to find the possible effect mechanism of these compounds.  相似文献   

2.
3.
The fluorotelomer alcohols (FTOHs) have been detected in various environmental compartments, including indoor and outdoor air, in North America and Europe. In our previous studies, FTOHs were detected at a relative higher concentration in outdoor air in the Keihan (Kyoto–Osaka, one of the major industrial zones) area, Japan compared to reported data. The exposure level of FTOHs in indoor air in the Keihan area remains unclear. In the present study, indoor air FTOH concentrations were investigated using a passive air sampler containing activated carbon felts. The indoor air sampling was conducted in 49 households of the Keihan area, during winter and summer 2008. Most samples contained 6:2 FTOH, 8:2 FTOH, 10:2 FTOH and 8:2 FTOAc. The median concentration of 8:2 FTOH (5.84 ng m?3) was highest among fluorotelomers, followed by those of 10:2 FTOH (1.12 ng m?3), 6:2 FTOH (0.29 ng m?3), and others. Significant correlations among fluorotelomers were observed in collected samples. The association between housing conditions and 8:2 FTOH concentrations showed that samples collected from bed rooms have higher 8:2 FTOH concentrations than those collected from other locations. In addition, samples collected in winter showed lower levels of 8:2 FTOH than those collected in summer. These findings suggest that 8:2 FTOH is the predominant component among fluorotelomers in indoor air, and that there are emission sources of fluorotelomers in indoor environments of the Keihan area. Further investigations into the origins of fluorotelomers are needed to evaluate indoor contamination with fluorotelomers.  相似文献   

4.
High volume air sampling in Bermuda, Sable Island (Nova Scotia) and along a cruise track from the Gulf of Mexico to northeast coast of the USA, was carried out to assess air concentrations, particle-gas partitioning and transport of polyfluorinated chemicals (PFCs) in this region. Samples were collected in the summer of 2007. Targeted compounds included the neutral PFCs: fluorotelomer alcohols (FTOHs), perfluoroalkyl sulfonamides (FOSAs) and perfluoroalkyl sulfonamido ethanols (FOSEs).Among the FTOHs, 8:2 FTOH was dominant in all samples. Sum of the concentration of FTOHs (gas+particle phase) were higher in Bermuda (mean, 34 pg m?3) compared to Sable Island (mean, 16 pg m?3). In cruise samples, sum of FTOHs were highly variable (mean, 81 pg m?3) reflecting contributions from land-based sources in the northeast USA with concentrations reaching as high as 156 pg m?3.Among the FOSAs and FOSEs, MeFOSE was dominant in all samples. In Bermuda, levels of MeFOSE were exceptionally high (mean, 62 pg m?3), exceeding the FTOHs. Sable Island samples also exhibited the dominance of MeFOSE but at a lower concentration (mean, 15 pg m?3). MeFOSE air concentrations (pg m?3) in cruise samples ranged from 1.6 to 73 and were not linked to land-based sources. In fact high concentrations of MeFOSE observed in Bermuda were associated with air masses that originated over the Atlantic Ocean.The partitioning to particles for 8:2 FTOH, 10:2 FTOH, MeFOSE and EtFOSE ranged from as high as 15 to 42% for cruise samples to 0.9 to 14% in Bermuda. This study provides key information for validating and developing partitioning and transport models for the PFCs.  相似文献   

5.
Neutral volatile and semi-volatile polyfluorinated organic compounds (PFC) and ionic perfluorinated compounds were determined in air samples collected at two sites in the vicinity of Hamburg, Germany, and onboard the German research vessel Atair during a cruise in the German Bight, North Sea, in early November 2007. PUF/XAD-2/PUF cartridges and glass fiber filters as sampling media were applied to collect several fluorotelomer alcohols (FTOH), fluorotelomer acrylates (FTA), perfluoroalkyl sulfonamides (FASA), and perfluoroalkyl sulfonamido ethanols (FASE) in the gas- and particle-phase as well as a set of perfluorinated carboxylates (PFCA) and sulfonates (PFSA) in the particle-phase. This study presents the distribution of PFC in ambient air of the German North Sea and in the vicinity of Hamburg for the first time. Average total PFC concentrations in and around Hamburg (180 pg m?3) were higher than those observed in the German Bight (80 pg m?3). In the German Bight, minimum–maximum gas-phase concentrations of 17–82 pg m?3 for ΣFTOH, 2.6–10 pg m?3 for ΣFTA, 10–15 pg m?3 for ΣFASA, and 2–4.4 pg m?3 for ΣFASE were determined. In the vicinity of Hamburg, minimum–maximum gas-phase concentrations of 32–204 pg m?3 for ΣFTOH, 3–26 pg m?3 for ΣFTA, 3–18 pg m?3 for ΣFASA, and 2–15 pg m?3 for ΣFASE were detected. Concentrations of perfluorinated acids were in the range of 1–11 pg m?3. FTOH clearly dominated the substance spectrum; 8:2 FTOH occurred in maximum proportions. Air mass back trajectories, cluster, and correlation analyses revealed that the air mass origin and thus medium to long range atmospheric transport was the governing parameter for the amount of PFC in ambient air. Southwesterly located source regions seemed to be responsible for elevated PFC concentrations, local sources appeared to be of minor importance.  相似文献   

6.

Introduction  

In this study, we explore the identity of a range of polyfluorinated surfactants (PFS) used for food contact materials, primarily to impart oil and water repellency on paper and board. PFS are of interest, as they can be precursors of poly- and perfluorinated alkyl substances (PFAS), of which several are persistent and are found worldwide in human blood and in the environment.  相似文献   

7.

Purpose  

The dyes and dye stuffs present in effluents released from textile dyeing industries are potentially mutagenic and carcinogenic. Phytoremediation technology can be used for remediating sites contaminated with such textile dyeing effluents. The purpose of the work was to explore the potential of Glandularia pulchella (Sweet) Tronc. to decolorize different textile dyes, textile dyeing effluent, and synthetic mixture of dyes.  相似文献   

8.
Adsorption of arsenic(V) by iron-oxide-coated diatomite (IOCD)   总被引:2,自引:0,他引:2  

Purposes and aims  

Economically efficient methods for removing arsenic from the drinking water supply are urgently needed in many parts of the world. Iron oxides are known to have a strong affinity for arsenic in water. However, they are commonly present in the forms of fine powder or floc, which limits their utility in water treatment. In this study, a novel granular adsorbent, iron-oxide-coated diatomite (IOCD), was developed and examined for its adsorption of arsenic from water.  相似文献   

9.

Purpose  

Nanoscale zero valent iron (NZVI) is emerging as a new option for the treatment of contaminated soil and groundwater targeting mainly chlorinated organic contaminants (e.g., solvents, pesticides) and inorganic anions or metals. The purpose of this article is to give a short overview of the practical experience with NZVI applications in Europe and to present a comparison to the situation in the USA. Furthermore, the reasons for the difference in technology use are discussed.  相似文献   

10.

Purpose  

Organophosphate pesticides (OPs) are among the most used insecticides in agriculture, causing the inhibition of esterases like acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and carboxylesterase (CbE). Pesticides can reach the aquatic environment, posing risks to non-target organisms, including tadpoles.  相似文献   

11.

Introduction  

Ambient air and bulk deposition samples were collected between June 2008 and June 2009. Eighty-three polychlorinated biphenyl (PCB) congeners were targeted in the samples.  相似文献   

12.

Purpose  

Instrumental capabilities and software tools of modern hybrid mass spectrometry (MS) instruments such as high-resolution mass spectrometry (HRMS), quadrupole time-of-flight (QTOF), and quadrupole linear ion trap (QLIT) were experimentally investigated for the study of emerging contaminants in Henares River water samples.  相似文献   

13.
The bioaccumulation of perfluorooctanesulfonamide (PFOSA) and two fluorotelomer alcohols (8:2 FTOH, 10:2 FTOH) by rainbow trout (Oncorhynchus mykiss) through dietary exposure, including depuration rates and metabolism was investigated. Concentrations in the spiked feed ranged from 10.9 μg g−1 wet weight (wet wt) for PFOSA and 6.7 μg g−1 wet wt for 8:2 FTOH to 5.0 μg g−1 wet wt for 10:2 FTOH. Trout was fed at 1.5% body weight per day for 30 d and depuration was followed for up to 30 d following previously published dietary exposure protocols. Perfluorooctanesulfonate (PFOS) was the major perfluoroalkylsulfonate (PFSA) detected in fish following dietary exposure to PFOSA. Half-lives of PFOS and PFOSA were 16.9 ± 2.5 and 6.0 ± 0.4 d, respectively. A biomagnification factor (BMF) of 0.023 was calculated for PFOSA which indicates that dietary exposure to PFOSA does not result in biomagnification in the rainbow trout. PFOS had a BMF of 0.08. The fluorotelomer saturated acids (8:2 FTCA, 10:2 FTCA) and fluorotelomer unsaturated acids (8:2 FTUCA, 10:2 FTUCA) were the major products detected in rainbow trout following dietary exposure to 8:2 FTOH and 10:2 FTOH, respectively. Half-lives were 3.7 ± 0.4, 2.1 ± 0.5, 3.3, and 1.3 d for 10:2 FTCA, 10:2 FTUCA, 8:2 FTCA, and 8:2 FTUCA, respectively. Small amounts of perfluorooctanoate (PFOA) and perfluorodecanoate (PFDA) were also detected in the FTOH exposed fish.  相似文献   

14.

Background, aim, and scope

According to their high sorption capacity polyethylene (PE) passive samplers are often used for the analysis of polycyclic aromatic hydrocarbons (PAHs) in the aquatic environment. PE is also one of the primary synthetic polymers found in oceans, and sorption of PAHs to marine PE debris may determine PAH exposure and therefore hazards in marine ecosystems. Thus, an understanding of the sorption process is of great importance. In the present study, the sorption of several PAHs with different polarities to low density polyethylene (LDPE) and high density polyethylene (HDPE) was studied in order to improve our understanding of the influence of material properties on the Fickian diffusion of PAHs into PE.

Materials and methods

Batch sorption experiments were performed with aqueous solutions containing acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, and LPDE or HDPE pellets. Samples were shaken in the dark at 20?±?1°C for 16 time intervals within one week. Concentrations of PAHs were determined in the aqueous samples using solid-phase microextraction coupled with gas chromatography–mass spectrometry. The distribution coefficients (K PE) between PE and water were estimated from different models reported in the literature. Kinetic sorption of the PAHs into the plastic pellets was described by a diffusion model based on Fick’s second law in spherical coordinates.

Results and discussion

A comparison between different models describing the equilibrium distribution of PAHs between PE and water revealed that the sorption equilibrium seemed to be driven by parameters other than, or in addition to, organic carbon. For both plastic types, diffusion coefficients decreased while the molecular weight of the PAHs increased which indicates a hindered diffusion through the matrix as a result of a larger molecule size. Higher diffusion coefficients were derived for LPDE than for HDPE indicating a greater sorption velocity for LPDE according to the lower polymer density.

Conclusions

Our results revealed that equilibrium time could be shortened during passive sampling as polymer membranes of lower density are used. In some areas, marine ecosystems may not be in equilibrium with respect to concentrations of organic contaminants and abundance of marine plastic debris. In such cases, different polymer densities should be taken into account in risk assessments.
  相似文献   

15.

Materials and methods  

The levels and possible sources of 16 polycyclic aromatic hydrocarbons (PAHs) were investigated in the surface sediments of Liaodong Bay, Bohai Sea, China.  相似文献   

16.

Purpose  

The purpose this research is to investigate the interaction of Cr(VI) species, present as Cr2O72−, at ambient temperature with brick clay pre-fired at different temperatures.  相似文献   

17.

Background, aim and scope  

Polychlorinated biphenyls (PCB) and dichlorodiphenyltrichloroethane (DDT) concentrations were determined in the liver of two deep sea fish species, Mediterranean slimehead and blackfin sorcerer, from the Adriatic Sea (southeastern Mediterranean Sea).  相似文献   

18.

Introduction  

A mercury (Hg) processing plant previously operating in KwaZulu-Natal Province (South Africa) discharged Hg waste into a nearby river system causing widespread contamination since the 1980s. Although the processing plant ceased operation in the 1990s, Hg contamination (due to residual Hg) remains significant. Previous studies in the area since the plant’s closure have found elevated Hg concentrations in fish, and that these concentrations were as a direct consequence of widespread contamination of the Hg processing plant operations conducted between the 1980s and 1990s.  相似文献   

19.

Purpose

This study has the objective to evaluate the lead(II) removal capacity of hydroxyapatite powder synthesized by microwave as an alternative method to decrease production time and cost.

Methods

Hydroxyapatite (HA) was synthesized by a microwave-assisted precipitation method using calcium nitrate and ammonium hydrogen phosphate as calcium and phosphorus sources, respectively. X-ray diffraction and Fourier transform infrared results clearly revealed that the resulting powder was HA with high purity and crystallinity. The obtained powder was used for the removal of lead(II) from aqueous solutions. The effects of pH, amount of adsorbent, initial lead(II) concentration, and contact time were studied in batch experiments.

Results

In the adsorption experiments, maximum lead(II) retention was obtained at pH 6. Adsorption equilibrium was established after 40 min. It was found that the adsorption of lead(II) on HA was correlated well (R 2?=?0.958) with the Freundlich equation for the concentration range studied. Both ion exchange and adsorption process were thought to exist in the removal process.

Conclusions

This study indicates that easily and rapidly synthesized HA by microwave-assisted precipitation method could be used as an efficient adsorbent for removal of lead(II) from aqueous solutions.  相似文献   

20.

Introduction  

Artisanal fisheries in tropical estuaries are an important economic activity worldwide. However, gear (e.g. ropes, nets, buoys, crates) and vessels are often in use under dangerous conditions. Polyfilament nylon ropes are used until they are well beyond human and environmental safety limits. Severe wear and tear results in the contamination of the environment with micro-fragments. The spread of these fragments in the marine environment and their ingestion by the biota are documented in the scientific literature and are increasing concerns. The aim of this study was to evaluate the ingestion of plastic fragments by two fish (drum) species in relation to seasonal, habitat and fish size–class variation.  相似文献   

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