Teaming up: The title reaction has been developed to deliver the product α‐alkylidene‐γ‐butyrolactones as single diastereomers with up to 98 % ee (see scheme; Ts=4‐toluenesulfonyl). The ...enantioselective process is catalyzed by 1, which contains both Lewis base and Brønsted acid moieties.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Background. Trypanosoma is a genus of unicellular parasitic flagellate protozoa. Trypanosoma brucei species and Trypanosoma cruzi are the major agents of human trypanosomiasis; other Trypanosoma ...species can cause human disease, but are rare. In March 2015, a 38-year-old woman presented to a healthcare facility in southern Vietnam with fever, headache, and arthralgia. Microscopic examination of blood revealed infection with Trypanosoma. Methods. Microscopic observation, polymerase chain reaction (PCR) amplification of blood samples, and serological testing were performed to identify the infecting species. The patient's blood was screened for the trypanocidal protein apolipoprotein L1 (APOL1), and a field investigation was performed to identify the zoonotic source. Results. PCR amplification and serological testing identified the infecting species as Trypanosoma evansi. Despite relapsing 6 weeks after completing amphotericin B therapy, the patient made a complete recovery after 5 weeks of suramin. The patient was found to have 2 wild-type APOL1 alleles and a normal serum APOL1 concentration. After responsive animal sampling in the presumed location of exposure, cattle and/or buffalo were determined to be the most likely source of the infection, with 14 of 30 (47%) animal blood samples testing PCR positive for T. evansi. Conclusions. We report the first laboratory-confirmed case of T. evansi in a previously healthy individual without APOL1 deficiency, potentially contracted via a wound while butchering raw beef, and successfully treated with suramin. A linked epidemiological investigation revealed widespread and previously unidentified burden of T. evansi in local cattle, highlighting the need for surveillance of this infection in animals and the possibility of further human cases.
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BFBNIB, NUK, PNG, UL, UM, UPUK
Unsubstituted and methylated polycyclic aromatic hydrocarbons (22 PAHs and 17 Me-PAHs) were examined in surface sediments collected from the Red River and four inner-city rivers of Hanoi City, ...Vietnam. Concentrations of total PAHs and Me-PAHs ranged from 52 to 920 (median 710) and from 70 to 2600 (median 1000) ng/g dry weight in samples of dry and wet seasons, respectively. Significant correlation was observed between total PAHs and organic carbon contents (Spearman's
ρ
= 0.782;
p
< 0.05). PAHs were more abundant than Me-PAHs in all samples and dominated by 4–6 ring compounds. The most predominant PAHs were benzo
ghi
perylene, benzo
b/j
fluoranthene, chrysene, pyrene, fluoranthene, and phenanthrene. Methylated derivatives of naphthalene, phenanthrene, anthracene, and benz
a
anthracene were frequently detected. The patterns of PAHs indicated principal pyrogenic sources (notably gasoline exhaust) in this highly urbanized area. The occurrence of several PAHs were occasionally associated with adverse effects on benthic organisms of the inner-city rivers.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
•Soils at open burning areas in Agbogbloshie had high PBDD/F and PCDD/F concentrations.•PXDFs were more abundant than PCDFs in open burning soils.•Median WHO-TEQ in open burning soils was 7 times ...higher than the U.S. action level.•WHO-TEQ contributors were in the order of PBDFs>>PCDD/Fs>PXDFs.
Although complex mixtures of dioxin-related compounds (DRCs) can be released from informal e-waste recycling, DRC contamination in African e-waste recycling sites has not been investigated. This study examined the concentrations of DRCs including chlorinated, brominated, mixed halogenated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs, PBDD/Fs, PXDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in surface soil samples from the Agbogbloshie e-waste recycling site in Ghana. PCDD/F and PBDD/F concentrations in open burning areas (18–520 and 83–3800ng/g dry, respectively) were among the highest reported in soils from informal e-waste sites. The concentrations of PCDFs and PBDFs were higher than those of the respective dibenzo-p-dioxins, suggesting combustion and PBDE-containing plastics as principal sources. PXDFs were found as more abundant than PCDFs, and higher brominated analogues occurred at higher concentrations. The median total WHO toxic equivalent (TEQ) concentration in open burning soils was 7 times higher than the U.S. action level (1000pg/g), with TEQ contributors in the order of PBDFs>>PCDD/Fs>PXDFs. DRC emission to soils over the e-waste site as of 2010 was estimated, from surface soil lightness based on the correlations between concentrations and lightness, at 200mg (95% confidence interval 93–540mg) WHO-TEQ over three years. People living in Agbogbloshie are potentially exposed to high levels of not only chlorinated but also brominated DRCs, and human health implications need to be assessed in future studies.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPUK, ZRSKP
Recent screening surveys have shown the presence of unknown halogenated compounds in the marine environment at comparable levels to persistent organic pollutants (POPs). However, their exposure ...levels and profiles in marine organisms and bioaccumulative potentials remain unclear. The present study performed nontarget/target screening of organohalogen compounds (OHCs) in mussel and sediment samples collected from Hiroshima Bay, Japan, in 2012 and 2018 by using integrated analyses of two-dimensional gas chromatography–high resolution time-of-flight mass spectrometry (GC×GC–HRToFMS) and magnetic sector GC–HRMS. Nontarget analysis by GC×GC–HRToFMS revealed the detection of approximately 60 OHCs including unknown mixed halogenated compounds (UHC-Br3–5Cl) with molecular formulae of C9H6Br3ClO, C9H5Br4ClO, and C9H4Br5ClO in the mussel. Interestingly, UHC-Br3–5Cl concentrations in the mussel samples, which were semi-quantified by GC–HRMS, were comparable to or higher than those of POPs at all the locations surveyed, and their geographical distribution patterns differed from those of other OHCs. These results suggest that UHC-Br3–5Cl are ubiquitous in coastal waters of Hiroshima Bay and derived from a specific source(s). The biota-sediment accumulation factors (BSAFs) of UHC-Br3–5Cl, estimated for a paired sample set of mussel (ng/g lw) and sediment (ng/g TOC), were 1 order of magnitude higher than those for POPs with similar log K ow values, indicating their high bioaccumulative potential.
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IJS, KILJ, NUK, PNG, UL, UM
Hatchery-reared Atlantic salmon (Salmo salar) has been released to support the wild salmon stocks in the Baltic Sea for decades. During their feeding migration, salmon are exposed to organohalogen ...compounds (OHCs). Here, we investigated the OHC levels and transcriptome profiles in the liver of wild and hatchery-reared salmon collected from the Baltic main basin (BMB), the Bothnian Sea (BS), and the Gulf of Finland (GoF) and examined whether salmon origin and OHC levels contributed to the hepatic transcriptome profiles. There were no differences in the OHC concentrations between wild and reared fish but larger differences between areas. Several transcript levels were associated with non-dioxin-like polychlorinated biphenyls, polybrominated diphenylethers, chlordanes, and dichlorodiphenyltrichloroethane in a concentration-dependent manner. Between wild and reared salmon, lipid metabolism and related signaling pathways were enriched within the BMB and BS, while amino acid metabolism was altered within the GoF. When comparing the different areas, lipid metabolism, environmental stress and cell growth, and death-related pathways were enriched. Class coinertia analysis showed that the covariation in the OHC levels and the transcriptome were significantly similar. These results suggest that the hepatic transcriptomes in wild and hatchery-reared salmon are more affected by the OHC levels rather than the origin of salmon.
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IJS, KILJ, NUK, PNG, UL, UM
Polybrominated diphenyl ethers (PBDEs) and selected novel brominated flame retardants (NBFRs) were examined in road dust samples collected from three representative areas in northern Vietnam, ...including seven inner districts of Hanoi metropolitan area, an industrial park in Thai Nguyen province and a rural commune in Bac Giang province. This study aims to provide basic information on the contamination status, potential sources and human exposure to PBDEs and NBFRs associated with road dust in northern Vietnam. PBDEs were detected in all the samples at a range of 0.91–56 ng g−1 with a median value of 16 ng g−1. PBDE concentrations in road dusts from urban sites were significantly higher than those from industrial zone and rural area, suggesting their environmental load related to urbanization in northern Vietnam. BDE-209, major component of deca-BDE technical mixtures, dominated the congener patterns in all samples, accounting for 60.8–91.9% of total PBDE levels. Decabromodiphenyl ethane, an alternative of deca-BDE, was observed in a detection frequency of 100% in urban and industrial areas and at levels comparable to those of BDE-209. Other NBFRs such as pentabromoethylbenzene, hexabromobiphenyl and 1,2-bis-(2,4,6-tribromophenoxy)ethane, were found at trace levels. Daily intake doses of PBDEs via road dust ingestion from 2.3 × 10−5 to 0.11 ng kg-bw−1 d−1 were estimated for residents in study areas, indicating a negligible risk with hazard indexes of 10−9 to 10−5 for selected congeners such as BDE-47, 99, 153 and 209.
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•The presence of PBDEs and some novel BFRs in Vietnamese road dusts was investigated.•PBDE and NBFR levels were higher in urban samples than industrial and rural ones.•BDE-209 was the most predominant PBDE congener in road dusts.•DBDPE was detected at levels comparable to BDE-209.•Road dust can contribute about 3% to total daily intake of PBDEs by Hanoi residents.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPUK, ZRSKP
Concentrations and congener-specific profiles of total 209 polychlorinated biphenyls (PCBs) were investigated in settled dust samples collected from end-of-life vehicle (ELV) processing, urban, and ...rural areas in northern Vietnam. Concentrations of total 209 PCBs, seven indicator congeners, and twelve dioxin-like PCBs decreased in the order: ELV working > ELV living ≈ urban > rural dusts. Penta- and hexa-CBs dominated the homolog patterns in all the samples with higher proportions in the ELV dusts compared to the urban and rural house dusts. The abundance and pattern of PCBs in the ELV dusts suggest on-going emissions of these compounds related to processing of vehicular oils and lubricants containing PCBs, whereas the presence of PCBs in the urban and rural house dusts indicate long-time releases. However, levels of some PCBs identified as by-products of pigment manufacturing (e.g., PCB-11 and PCB-209) were higher in the urban house dusts than those from other locations, resulting from human activities utilizing paints and pigments. Daily intake doses (ID), non-carcinogenic hazard quotient (HQ), and lifetime cancer risk (CR) of PCBs through dust ingestion were estimated for ELV workers and residents in the studied areas. The workers and children in the ELV sites were estimated to be at higher risk of PCB exposure, however almost all of the HQ < 1 and CR < 10−4 indicate no serious risk related to dust-bound PCBs.
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•Informal end-of-life vehicle processing activities were potential PCB sources.•Σ209PCBs were higher in the ELV dusts than normal house dusts.•Concentrations of PCB-11 were higher in the urban house dusts.•ELV workers and children were at higher risk of exposure to dust-bound PCBs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPUK, ZAGLJ, ZRSKP
The occurrence and profiles of 19 polycyclic aromatic hydrocarbons (PAHs) and 15 methylated derivatives (Me-PAHs) were examined in settled dust samples collected from workplaces and living areas of ...an informal end-of-life vehicle (ELV) processing village, and house dusts from urban and rural areas in northern Vietnam. Concentrations of total PAHs and Me-PAHs decreased in the order: ELV workplace (median 5700, range 900–18,000 ng g−1) > rural house (3700, 1800–6200 ng g−1) > urban house (1800, 620–3100 ng g−1) ≈ ELV living dusts (1000, 600–3900 ng g−1). PAHs with 4 rings or more dominated in almost all the samples, indicating the abundance of pyrogenic sources (e.g., vehicular emissions and domestic thermal processes). Levels of Me-PAHs were exceeded those of PAHs in several ELV samples, revealing specific petrogenic sources derived from vehicle processing activities. Results from source apportionment analysis have partially identified traffic emission, biomass and coal combustion, and mixed petrogenic-pyrogenic sources related to ELV waste as the major sources of PAHs and Me-PAHs in the urban, rural, and ELV areas, respectively. Daily intake doses and health risk related to PAHs and Me-PAHs in settled dusts were estimated for ELV workers and residents living in the study areas. The worst exposure scenario of dust-bound PAHs showed a potential cancer risk for the ELV workers, meanwhile, no significant non-cancer and cancer risk was expected for other exposed groups. A more comprehensive and accurate risk assessment of PAHs and related compounds should be conducted in Vietnam.
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•PAHs/Me-PAHs were examined in Vietnamese workplace/house dusts for the first time.•Total PAHs decreased in the order: ELV working > rural > urban ≈ ELV living dusts.•Pyrogenic compounds dominated PAH patterns in almost all the samples.•The ELV dusts were contaminated by petrogenic PAHs from vehicle processing.•The worst exposure scenario showed a potential cancer risk for ELV workers.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPUK, ZAGLJ, ZRSKP
Improper processing activities of e-waste are potential sources of polycylic aromatic hydrocarbons (PAHs) and their derivatives, however, information about the environmental occurrence and adverse ...impacts of these toxic substances is still limited for informal e-waste recycling areas in Vietnam and Southeast Asia. In this study, unsubstituted and methylated PAHs were determined in surface soil and river sediment samples collected from a rural village with informal e-waste recycling activities in northern Vietnam. Total levels of PAHs and MePAHs decreased in the order: workshop soil (median 2900; range 870–42,000 ng g−1) > open burning soil (2400; 840–4200 ng g−1) > paddy field soil (1200; range 530–6700 ng g−1) > river sediment samples (750; 370–2500 ng g−1). About 60% of the soil samples examined in this study were heavily contaminated with PAHs. Fingerprint profiles of PAHs and MePAHs in the soil and sediment samples indicated that these pollutants were mainly released from pyrogenic sources rather than petrogenic sources. The emissions of PAHs and MePAHs in this area were probably attributed to uncontrolled burning of e-waste and agricultural by-products, domestic coal and biomass combustion, and traffic activities. Carcinogenicity and mutagenicity of PAHs in the e-waste workshop soils were significantly higher than those of the field soils; however, the incremental lifetime cancer risk of PAH-contaminated soils in this study ranged from 5.5 × 10−9 to 4.6 × 10−6, implying acceptable levels of human health risk. Meanwhile, concentrations of some compounds such as phenanthrene, anthracene, fluoranthene, benzaanthracene, and benzoapyrene in several soil samples exceeded the maximum permissible concentrations, indicating the risk of ecotoxicological effects.
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•PAHs and MePAHs were found in e-waste soil and sediment at elevated concentrations.•PAH/MePAH levels decreased: workshop ≈ open burning > field soil > sediment.•Mixed pyrogenic sources were revealed, e.g., e-waste, biomass, and coal combustion.•Cancer risk of PAH-contaminated soil was generally acceptable.•Some PAHs may exhibit ecotoxicological risk for soil and freshwater life.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPUK, ZAGLJ, ZRSKP
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