| 1. |
- Dosis, Ioannis, et al.
(författare)
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Polybrominated diphenyl ethers (PBDEs) in mussels from cultures and natural population
- 2016
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Ingår i: Marine Pollution Bulletin. - : Elsevier BV. - 0025-326X .- 1879-3363. ; 107:1, s. 92-101
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Tidskriftsartikel (refereegranskat)abstract
- Polybrominated diphenyl ether (PBDE) mass fractions were determined in mussel samples collected from 6 locations around Thermaikos Gulf in north Greece. PBDEs were present in all sampling sites and the average total (2,PBDEs) ranged from 17.7 to 323 ng/g l.w., characterising Thermaikos as low polluted, a fact further supported by congener ratios and literature comparison. Distribution was even among stations with one exception. Congener profiles exhibited predominance of penta-/octa-BDEs as well as BDE-209. Statistical analysis showed significant difference in pollution levels between the two types of mussel cultures. No variations were observed for mussel bunch position or between cultures and natural population. Congener correlation analysis suggested different pollution sources between higher and lower brominated congeners as well as different metabolic/degradation processes. Bioaccumulation factors indicated that an increase in congener bromination degree leads to bioaccumulation capacity reduction. Consumption of mussels from Thermaikos gulf area poses no threat for public health concerning PBDEs.
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| 2. |
- Yin, Ge, et al.
(författare)
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A refined method for analysis of 4,4 '-dicofol and 4,4 '-dichlorobenzophenone
- 2017
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Ingår i: Environmental Science and Pollution Research. - : Springer Science and Business Media LLC. - 0944-1344 .- 1614-7499. ; 24:15, s. 13307-13314
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Tidskriftsartikel (refereegranskat)abstract
- The acaricide, dicofol, is a well-known pesticide and partly a substitute for dichlorodiphenyltrichloroethane (DDT). Only few reports on environmental occurrence and concentrations have been reported calling for improvements. Hence, an analytical method was further developed for dicofol and dichlorobenzophenone (DCBP) to enable assessments of their environmental occurrence. Concentrated sulfuric acid was used to remove lipids and to separate dicofol from DCBP. On-column injection was used as an alternative to splitless injection to protect dicofol from thermal decomposition. By the method presented herein, it is possible to quantify dicofol and DCBP in the same samples. Arctic cod (Gadus morhua) were spiked at two dose levels and the recoveries were determined. The mean recovery for dicofol was 65% at the low dose (1 ng) and 77% at the high dose (10 ng). The mean recovery for DCBP was 99% at the low dose (9.2 ng) and 146% at the high dose (46 ng). The method may be further improved by use of another lipid removal method, e.g., gel permeation chromatography. The method implies a step forward in dicofol environmental assessments.
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| 3. |
- Carlsson, Gunnar, et al.
(författare)
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Thyroid disruption properties of three indoor dust chemicals tested in Silurana tropicalis tadpoles
- 2019
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Ingår i: Journal of Applied Toxicology. - : Wiley. - 0260-437X .- 1099-1263. ; 39:9, s. 1248-1256
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Tidskriftsartikel (refereegranskat)abstract
- Indoor dust contains a multitude of industrial chemicals, and ingestion of dust is considered an important exposure route to organic contaminants. Some of these contaminants have been shown to interfere with the thyroid system, which may result in significant consequences on public health. The amphibian metamorphosis is a thyroid hormone-dependent process, which can be used as an in vivo model for studies on thyroid hormone-disrupting potency. Three contaminants of indoor dust were tested on metamorphosing Silurana (Xenopus) tropicalis tadpoles. The tested chemicals were Tris (1,3-dichloroisopropyl) phosphate (TDCiPP), tetrabromobisphenol-A (TBBPA) and propylparaben (PrP). Measurements reflecting general growth, development progress and thyroid epithelial cell height were performed on the exposed tadpoles as well as chemical analyses of the exposure water. It was shown that TDCiPP acts as a thyroid hormone-disrupting chemical in metamorphosing tadpoles by causing increased epithelial cell height in thyroid glands after exposure to a nominal concentration of 0.010 mg/L and in higher concentrations. TBBPA caused reductions in general growth of tadpoles at the nominal concentration 0.125 mg/L, and PrP caused acute toxicity at the nominal concentration 12.5 mg/L. However, no evident indications of specific thyroid-disrupting effects caused by TBBPA or PrP were observed.
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| 4. |
- Castro, Mafalda, et al.
(författare)
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Partitioning of Chlorinated Paraffins (CPs) to Daphnia magna Overlaps between Restricted and in-Use Categories
- 2018
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 52:17, s. 9713-9721
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Tidskriftsartikel (refereegranskat)abstract
- Chlorinated paraffins (CPs) are high-production volume industrial chemicals consisting of n-alkanes (with 10 to 30 carbon atoms in the chain) with chlorine content from 30 to 70% of weight. In Europe, the use of short chain chlorinated paraffins (SCCPs) has been restricted by the Stockholm Convention on POPs due to their PBT (persistent, bioaccumulative and toxic) properties. Medium (MCCPs) and long chain (LCCPs) chlorinated paraffins are used as substitution products. In this work we studied the partitioning behavior of five different CP technical mixtures from the established categories (2 SCCPs, 1 MCCP, 1 LCCP and 1 CP technical mixture covering all categories) using passive dosing, by determining the partitioning coefficient of CP technical mixtures between silicone and water (Ksilicone-water) as well as between organic matter and water (Koc-water). We show that both silicone-water and organic carbon water partition coefficients overlap between different categories of CP technical mixtures. These results indicate that in-use MCCPs and LCCPs may be equally or more bioaccumulative than restricted SCCPs. For the tested mixtures, both chlorine content and carbon chain length showed a significant correlation with both Ksilicone-water and Koc-water.
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| 5. |
- Norrgran Engdahl, Jessica, et al.
(författare)
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Cats' Internal Exposure to Selected Brominated Flame Retardants and Organochlorines Correlated to House Dust and Cat Food
- 2017
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 51:5, s. 3012-3020
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Tidskriftsartikel (refereegranskat)abstract
- Pet cats may be used as a biomarker for assessing exposures to organohalogen compounds (OHCs) adsorbed to household dust in home environments. This study explores two exposure routes of OHCs, ingestion of OHCs (i) via house dust and (ii) via cat food. House dust from 17 Swedish homes and serum from the participating families' pet cats were collected, and cat food was purchased matching the diet reported. Paired samples of cat serum, house dust, and cat food were analyzed for brominated flame retardants/natural products (polybrominated diphenyl ethers (PBDEs), decabromobiphenyl (BB-209), decabromodiphenyl ethane (DBDPE), 2,4,6-tribromophenol (2,4,6-TBP), OH-PBDEs) and organochlorines (polychlorinated biphenyls (PCBs), 1,1-bis(4,4'-dichlorodipheny1)-2,2,2-trichloroethane (4,4'-DDT), 1,1-bis(4,4'-dichlorodiphenyl)-2,2-dichloroethene (4,4'-DDE), hexachlorobenzene (HCB), pentachlorophenol (PCP)). Significant correlations were found between serum and dust samples from the living rooms for BDE-47 (p < 0.035), BDE-99 (p < 0.035), and BDE-153 (p < 0.039), from the adult's bedroom for BDE-99 < 0.019) and from all rooms for BDE-99 (p < 0.020) and BB-209 (p < 0.048). This is the first time a correlation between cat serum levels and household dust has been established, a finding that supports the hypothesis that dust is a significant exposure route for cats. Serum levels were also significantly correlated with concentrations found in cat food for 6-OH-BDE47 (p < 0.002), 2,4,6-TBP (p < 0.035), and BB-209 (p < 0.007). DBDPE was found in high concentrations in all dust (median 154 pmol/g) and food samples (median 0.7 pmol/ig lw) but was below detection in serum samples, suggesting low or no bioavailability for DBDPE in cats.
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| 6. |
- Norrgran, Jessica, 1979-, et al.
(författare)
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Higher PBDE Serum Concentrations May Be Associated with Feline Hyperthyroidism in Swedish Cats
- 2015
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 49:8, s. 5107-5114
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Tidskriftsartikel (refereegranskat)abstract
- Serum from 82 individual cats was analyzed for decabromobiphenyl (BB-209), polybrominated diphenyl ethers (PBDEs), hydroxylated PBDEs (OH-PBDEs), and 2,4,6-TBP in order to study differences in body burden between healthy and sick cats diagnosed with Feline Hyperthyroidism (FH). Within the study group, 60 of these cats had a euthyroid (n = 23) or hyperthyroid (n = 37) status, all of which were used in the comparison. This study shows that hyperthyroid compared to euthyroid cats have higher serum concentrations for some of the investigated PBDEs (BDE-99, BDE-153, and BDE-183) and CB-153 on a fat weight basis. Further, it is intriguing, and beyond explanation, why the flame retardant BB-209 (discontinued in 2000) is present in all of the cat serum samples in concentrations similar to BDE-209. Median BDE-47/-99 ratios are 0.47 and 0.32 for healthy and euthyroid cats, respectively, which differs significantly from Swedes, where the ratio is 3.5. Another important finding is the occurrence of very low levels or the absence of hydroxylated PBDE metabolites in the cats. In addition, the major OH-PBDE, 6-OH-BDE47, is likely of natural origin, probably ingested via cat food. The statistics indicate an association between elevated PBDE concentrations in the cats and FH.
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| 7. |
- Svengren, Henrik, et al.
(författare)
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A transition metal oxofluoride offering advantages in electrocatalysis and potential use in applications
- 2016
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Ingår i: Faraday discussions. - : Royal Society of Chemistry (RSC). - 1359-6640 .- 1364-5498. ; 188, s. 481-498
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Tidskriftsartikel (refereegranskat)abstract
- The recently described solid solution ( Co,Ni,Mn)(3)Sb4O6F6 has proved stable and efficient as a catalyst for electrocatalytic water oxidation. The end component Co3Sb4O6F6 was found to be most efficient, maintaining a current density of j = 10 mA cm(-2) at an overpotential of 443 mV with good capability. At this current density, O-2 and H-2 were produced in the ratio 1 : 2 without loss of faradaic current against a Pt-cathode. A morphological change in the crystallite surface was observed after 0.5 h, however, even after 64.5 h, the overall shape and size of the small crystallites were unaffected and the electrolyte contained only 0.02 at% Co. It was also possible to conclude from in situ EXAFS measurements that the coordination around Co did not change. The oxofluorides express both hydrophilic and hydrophobic surface sites, incorporate a flexible metalloid element and offer the possibility of a mechanism that differs from other inorganic catalytic pathways previously described.
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| 8. |
- Svengren, Henrik, et al.
(författare)
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An Oxofluoride Catalyst Comprised of Transition Metals and a Metalloid for Application in Water Oxidation
- 2015
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Ingår i: Chemistry - A European Journal. - : Wiley. - 0947-6539 .- 1521-3765. ; 21:37, s. 12991-12995
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Tidskriftsartikel (refereegranskat)abstract
- The application of the recently discovered oxofluoride solid solution (CoxNi1-x)(3)Sb4O6F6 as a catalyst for water oxidation is demonstrated. The phase exhibits a cubic arrangement of the active metal that forms oxo bridges to the metalloid with possible catalytic participation. The Co3Sb4O6F6 compound proved to be capable of catalyzing 2H(2)OO(2)+4H(+)+4e(-) at 0.33V electrochemical and 0.39V chemical overpotential with a TOF of 4.410(-3), whereas Ni3Sb4O6F6 needs a higher overpotential. Relatively large crystal cubes (0.3-0.5mm) are easily synthesized and readily handled as they demonstrate both chemical resistance to wear after repeated insitu tests under experimental conditions, and have a mechanical hardness of 270V0.1 using Vickers indentation. The combined properties of this compound offer a potential technical advantage for incorporation to a catalytic interface in future sustainable fuel production.
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| 9. |
- Yin, Ge, et al.
(författare)
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Spatial distribution and bioaccumulation of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in snails (Bellamya aeruginosa) and sediments from Taihu Lake area, China
- 2017
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Ingår i: Environmental Science and Pollution Research. - : SPRINGER HEIDELBERG. - 0944-1344 .- 1614-7499. ; 24:8, s. 7740-7751
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Tidskriftsartikel (refereegranskat)abstract
- Taihu Lake area is one of the densest metropolitan areas in the world including diverse industrial activity. In the present study, the snail (Bellamya aeruginosa) and sediment were collected from the Taihu Lake area to investigate the contamination status, congener pattern, spatial distribution, and bioaccumulation effect of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). The samples underwent liquid extraction, lipid removal by sulfuric acid, and acidic silica gel column, and subsequently analyzed by gas chromatography-electron capture detector (GC-ECD) and gas chromatography-mass spectrometry (GC-MS). Concentration of S22PCBs ranged between 90 and 680 ng g(-1) lipid weight in the snails and between 0.018 and 0.82 ng g(-1) dry weight in the sediments. Concentration of S24PBDEs varied from 25 to 200 ng g(-1) lipid weight in the snails and from 0.62 to 67 ng g(-1) dry weight in the sediments. The levels of PCBs and PBDEs observed were in the medium to low range compared with other studies in the world. CB-153 was the predominant PCB congener in both snails and sediments whereas BDE-209 showed a low bioavailability in the snails, even if it contributed up to 70% of S24PBDEs in the sediments. The spatial distribution showed that the highest concentration of PCBs and PBDEs were detected in samples from Zhushan Lake. East Taihu Lake and Dianshan Lake showed lower concentration of PCBs and PBDEs than the other sampling sites. Biota-sediment accumulation was found between snails and sediments of most of PCB and PBDE congeners except for the highly brominated BDEs (i.e., BDE-209). Therefore, sediment is suggested to be an appropriate matrix to monitor BDE-209 while aquatic species such as the snail could be good for monitoring of PCBs and lower brominated BDE congeners. No significant correlation (Spearman correlation test, two-tailed) of CB-153 (r = 0.54, p = 0.27) or BDE-47 (r = 0.60, p = 0.21) was found between snails and sediments.
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| 10. |
- Zhou, Yihui, et al.
(författare)
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Extensive organohalogen contamination in wildlife from a site in the Yangtze River Delta
- 2016
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 554, s. 320-328
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Tidskriftsartikel (refereegranskat)abstract
- The environmental and human health concerns for organohalogen contaminants (OHCs) extend beyond the 23 persistent organic pollutants (POPs) regulated by the Stockholm Convention. The current, intense industrial production and use of chemicals in China and their bioaccumulation makes Chinese wildlife highly suitable for the assessment of legacy, novel and emerging environmental pollutants. In the present study, six species of amphibians, fish and birds were sampled from paddy fields in the Yangtze River Delta (YRD) were screened for OHCs. Some extensive contamination was found, both regarding number and concentrations of the analytes, among the species assessed. High concentrations of chlorinated paraffins were found in the snake, Short-tailed mamushi (range of 200-340 mu g g(-1) lw), Peregrine falcon (8-59 mu g g(-1) lw) and Asiatic toad (97 mu g g(-1) lw). Novel contaminants and patterns were observed; octaCBs to decaCB made up 20% of the total polychlorinated biphenyls (PCBs) content in the samples and new OHCs, substituted with 5-8 chlorines, were found but are not yet structurally confirmed. In addition, Dechlorane 602 (DDC-DBF) and numerous other OHCs (DDTs, hexachlorocyclohexanes (HCHs), polybrominated diphenyl ethers (PBDEs), hexbromocyclododecane (HBCDD), chlordane, heptachlor, endosulfan and Mirex) were found in all species analyzed. These data show extensive chemical contamination of wildlife in the YRD with a suite of OHCs with both known and unknown toxicities, calling for further indepth studies.
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