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1.
Environ Pollut ; 262: 114328, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32443216

RESUMO

The distributions of chlorinated paraffins (CPs) in soils and their ecological effects attract much attention, while site-scale data are still scarce. In this study, a comprehensive investigation was performed to understand the CP distributions at a CP production plant brownfield site, as well as their effects on soil microbial community. Short-, medium- and long-chain CPs (SCCPs, MCCPs, LCCPs) were detected in most samples with total contents ranging ND-5,090, ND-6,670, and ND-1450 ng g-1 (dw), respectively. A CP-hotspot was observed 10 m beneath the synthesis workshop, indicating the downward migration of CPs. The consistence of soil SCCP congener profiles with commercial product CP-52 suggested the leakage of CP products as the contamination source. Besides CPs, petroleum hydrocarbons (PHC) contamination also occurred beneath the synthesis workshop. Soil microbial community composition and diversity were significantly influenced by SCCPs (p < 0.05) despite their lower contents compared to other concerned contaminants. Microbial network analysis indicated nonrandom co-occurrence patterns, with Acinetobacter, Brevibacterium, Corynebacterium, Microbacterium, Stenotrophomonas, and Variibacter as the keystone genera. Genera from the same module showed significant ecological links (p < 0.05) and were involved in the degradation of PHCs and chlorinated organic contaminants. This study provides the first phylogenetic look at the microbial communities in CP contaminated soils, indicating that the long-term exposure to CPs and PHCs may lead to microbial group assemblages with the potential for degradation.


Assuntos
Hidrocarbonetos Clorados/análise , Microbiota , China , Monitoramento Ambiental , Parafina/análise , Filogenia , Solo
2.
Chemosphere ; 255: 126959, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32388263

RESUMO

The photolytic chlorination of n-alkanes in presence of sulfuryl chloride (SO2Cl2) was explored to produce new standard materials. Five mixtures of chlorinated tetradecanes were synthesized with chlorination degrees (mCl,EA) varying from 43.7% to 59.4% (m/m) based on elemental analysis. Chlorine-enhanced negative chemical ionization mass spectrometry (CE-NCI-MS) forcing the formation of chloride-adduct ions [M+Cl]- was applied to characterize these materials which all contained tetra-to deca-chlorinated paraffins. Deconvolution of respective mass spectra revealed the presence of chlorinated olefins (COs). CO levels were highest in materials, which were exposed longest. All synthesized materials also contained two classes of polar impurities, tentatively assigned as sulfite- and sulfate-diesters with molecular formulas of C14H28-xO3SClx (x = 1-4) and C14H28-xO4SClx (x = 3-6), respectively. MS data were in accordance with the proposed structures but further work is needed to deduce their constitutions. These compounds are thermolabile and were not detected with GC-MS methods. We could remove these sulfur-containing impurities from the CPs with normal-phase liquid chromatography. In conclusion, single-chain CP materials were synthesized via chlorination of n-alkanes with sulfuryl chloride, but these materials contained reactive side products which should be removed to gain non-reactive and stable CP materials suitable as standards and for fate and toxicity studies.


Assuntos
Hidrocarbonetos Clorados/química , Alcanos , Alcenos , Cloro/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Halogenação , Hidrocarbonetos Clorados/análise , Espectrometria de Massas/métodos , Parafina/análise
3.
Sci Total Environ ; 728: 137998, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32361102

RESUMO

Human exposure to chlorinated paraffins (CPs) has been expected and assessed by external pathways considering their pervasive environmental occurrence. However, the deficiency of external exposure assessment in characterizing human burden is unavoidable. In addition, the associations between health outcomes and CP contents in human biospecimen are rarely assessed. In this study, we reported the occurrence and homologue profiles of short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) in serum samples from 145 residents aged from 50 to 84 in Jinan, Shandong Province of China using quadrupole time-of-flight high-resolution mass spectrometry coupled with atmospheric pressure chemical ionization source operated in negative ion mode (APCI-qTOF-HRMS). The associations between serum CP concentrations and hematologic parameters were further analyzed by linear regression. We identified high level of ∑SCCPs (median = 107 ng/g wet weight, ww; 13,800 ng/g lipid, lw), ∑MCCPs (median = 134 ng/g ww; 15,200 ng/g lw) and elevated ∑MCCPs/∑SCCPs (median = 1.12) in serum of the studied population. C13-CPs and C14-CPs were the most abundant SCCP and MCCP groups, respectively. While the predominant chlorine homologues among SCCPs and MCCPs were Cl7-8-CPs. ∑SCCPs, ∑MCCPs, ∑MCCPs/∑SCCPs and the homologue patterns presented no significant variance among age, sex and BMI groups. Further explorations suggested that perturbation of hematologic homeostasis could be induced by CP exposure in a sex-specific way, reflected by significant negative associations of serum SCCP and MCCP concentrations in lipid weight basis with sex-specific hematologic parameters. This study suffered from some limitations and should be interpreted with caution. However, the CP burdens of residents in China and the subsequent health risks must be underscored.


Assuntos
Hidrocarbonetos Clorados/análise , Parafina/análise , China , Cloro , Monitoramento Ambiental , Humanos
4.
Environ Pollut ; 263(Pt B): 114520, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32283402

RESUMO

Short-chain chlorinated paraffin (SCCP) concentrations in 419 food samples (from 59 species) from Republic of Korea were determined. The SCCP concentrations and lipid contents in whole foods positively correlated and the highest SCCP concentration (891 ng/g wet weight) was observed in fats and oils. The SCCP concentrations were higher in benthic fish/shellfish and demersal fish than other fish and shellfish. The SCCP concentrations were higher in duck meat and eggs than meat and eggs of other species. The chlorine-based congener group patterns were related to the lipid contents of the foods. SCCPs in eggs (high lipid content) were dominated by more-chlorinated SCCPs (particularly Cl8-SCCPs, which contributed 43% of the total) but SCCPs in seaweed (low lipid content) were dominated by less-chlorinated SCCPs (particularly Cl6-SCCPs, which contributed 46%). Dietary SCCP intakes were calculated using the median SCCP concentrations and estimated 888 and 781 ng/kg/d for male and female Korean adults, respectively. The predominant contributing foods to SCCP dietary exposure differed according to sex and age. Dairy products contributed most (about 50%) for infants/children (1-5 y old), but meat and dairy products contributed most for adult males and females, respectively. Grain contributed most for ≥65 y old.


Assuntos
Hidrocarbonetos Clorados/análise , Parafina/análise , Adulto , Animais , Criança , China , Exposição Dietética , Monitoramento Ambiental , Feminino , Humanos , República da Coreia
5.
Arch Environ Contam Toxicol ; 78(4): 501-512, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32123944

RESUMO

Short-chain chlorinated paraffins (SCCPs) were included in the Stockholm Convention in 2017. SCCPs have persistence, bioaccumulation, long-range environmental mobility and biological toxicity, significant toxicity to aquatic organisms, and potential carcinogenicity. Little study was on the progress research on the current environmental pollution in China. We reviewed the pollution conditions of SCCPs in air, soil, and water and their accumulation in food and organisms in China, especially for the contaminations of aquatic ecosystem. Meanwhile, we summarize the recent studies on the toxic effects and toxicological mechanisms of SCCPs on aquatic organisms and mammals. Finally, the further direction and trends for SCCP research were proposed. More efforts are necessary to conduct a comprehensive risk assessment and evaluate the relative importance of the various exposure routes.


Assuntos
Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Hidrocarbonetos Clorados/toxicidade , Parafina/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Organismos Aquáticos/efeitos dos fármacos , China , Ecossistema , Hidrocarbonetos Clorados/química , Parafina/química , Poluentes Químicos da Água/química
6.
Medicine (Baltimore) ; 99(12): e19519, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32195954

RESUMO

BACKGROUND: The purposes of this study were to examine the feasibility of using the MyotonPRO digital palpation device in measuring the passive stiffness of gastrocnemius muscle belly and Achilles tendon; to determine between-days test-retest reliability of MyotonPRO; and to evaluate the acute effect of paraffin therapy on stiffness measurements in healthy participants. METHODS: It is a randomized controlled trial. Twenty healthy participants (male, n = 10; female, n = 10; total, n = 20) were recruited to evaluate the passive stiffness of gastrocnemius muscle belly and Achilles tendon. Dominant and nondominant legs were randomly divided into an experimental side (20 cases) and a control side (20 cases). The experimental side received 20 minutes of paraffin therapy. RESULTS: The stiffness of muscle and tendon in the experimental side decreased significantly after paraffin therapy (P < .01), whereas no significant differences in stiffness measurements were found in the control side (P > .05). The passive stiffness of muscle and tendon was positively correlated with the ankle from 30° plantar flexion to10° dorsiflexion for dominant legs. Between-days test-retest reliability in stiffness measurements was high or very high (ICCs were above 0.737). CONCLUSION: Paraffin therapy induces a decrease in the passive stiffness of gastrocnemius muscle belly and Achilles tendon. Furthermore, the MyotonPRO can reliably determine stiffness measurements.


Assuntos
Tendão do Calcâneo/efeitos dos fármacos , Hidrocarbonetos/uso terapêutico , Tono Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Parafina/uso terapêutico , Tendão do Calcâneo/fisiopatologia , Adolescente , Adulto , Articulação do Tornozelo/fisiologia , Feminino , Humanos , Masculino , Músculo Esquelético/fisiopatologia , Modalidades de Fisioterapia/tendências , Amplitude de Movimento Articular/fisiologia , Reprodutibilidade dos Testes , Adulto Jovem
7.
Food Chem ; 319: 126583, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32187566

RESUMO

This study established a simple and rapid method for determination of short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) by dispersive liquid-liquid micro-extraction coupled with high performance liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (HPLC-ESI-Q-TOF/MS) in white and red wines. Affecting variables, including extraction solvent, salt concentration, ultrasound-vortex conditions and ethanol content, were evaluated. Under optimized conditions, the limit of detection (LODs) for SCCPs and MCCPs were in the range of 0.15-3.00 ng mL-1 and 0.08-2.50 ng mL-1, respectively. The spiked recoveries of SCCPs and MCCPs from white and red wine ranged from 63.2% to 127%. The method is precise with intra- and inter-day variations within 14.0% and 17.0%, respectively. SCCPs and MCCPs in wines from china varied widely, from

Assuntos
Análise de Alimentos/métodos , Microextração em Fase Líquida/métodos , Parafina/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Vinho/análise , China , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Alimentos/análise , Hidrocarbonetos Clorados/análise , Limite de Detecção , Parafina/química
8.
Environ Sci Technol ; 54(7): 4356-4366, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32101003

RESUMO

Short-, medium-, and long-chain chlorinated paraffins (SCCPs, MCCPs, and LCCPs) were analyzed in human milk from the Yangtze River Delta (YRD) and Scandinavia. Individual samples were collected from Shanghai, Jiaxing, and Shaoxing (China), Stockholm (Sweden), and Bodø (Norway) between 2010 and 2016. Mean concentrations (range) of SCCPs, MCCPs, and LCCPs in samples from the YRD were 124 [

Assuntos
Hidrocarbonetos Clorados , Parafina , China , Monitoramento Ambiental , Humanos , Lactente , Leite Humano , Noruega , Suécia
9.
Environ Pollut ; 261: 114141, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32062093

RESUMO

Atmospheric levels of chlorinated paraffins (CPs) at five remote, six rural and four urban sites in Australia were measured using XAD-2 passive air samplers (XAD-PAS). While long-chain CP (LCCP, C>17) levels were below method detection limits (MDLs), short-chain CPs (SCCPs, C10-13) and, for the first time, medium-chain CPs (MCCPs, C14-17) and CPs with a carbon chain length of nine (CP-C9) were found at many sites (88%, 81% and 88%, respectively) across the Australian continent, representing a range of environmental conditions. Applying preliminary sampling rates of the XAD-PAS for CPs, gaseous CP levels in Australian air were

Assuntos
Hidrocarbonetos Clorados/análise , Parafina/análise , Regiões Antárticas , Austrália , China , Monitoramento Ambiental , Humanos
10.
Environ Pollut ; 259: 113958, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32023802

RESUMO

Research on the atmospheric occurrence of short chain chlorinated paraffins (SCCPs) in industrialized areas is scarce. In this study, we investigated the concentrations, profile, and spatial distribution of SCCPs in the highly industrialized and developed areas of the Yangtze River Delta (YRD) in China using polyurethane foam passive air samplers. Sampling was performed during two separate periods in 2011. The concentrations of atmospheric SCCPs ranged from 6.1 to 63 ng m-3 in summer and 6.2-42 ng m-3 in winter. The C10 and C11 groups were the predominant carbon groups in all the samples. Different congener patterns between summer and winter were found, indicating that congeners in the air in winter may be influenced by local and external sources. The highest level of SCCPs was found in Suzhou, which is a highly industrialized area with many manufactories including electronic industries and plastic factories. Higher levels of SCCPs were found in the air than polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ether (PBDEs), suggesting that the production and use of SCCPs were much higher than prohibited or restricted persistent organic pollutants (e.g., PCBs, OCPs, and PBDEs). Future studies should investigate the different sources of atmospheric SCCPs by conducting a comprehensive assessment of SCCP exposure.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Parafina/análise , China , Hidrocarbonetos Clorados , Rios
11.
J Chromatogr A ; 1619: 460927, 2020 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-32014290

RESUMO

Chlorinated paraffins (CPs), or polychlorinated n-alkanes, form a complex family of chemicals as they exist as mixtures of several thousands of isomers. To facilitate their classification, they are subdivided into short-chains (C10C13, SCCPs), medium-chains (C14C17, MCCPs), and long-chains (C≥18, LCCPs) and further subdivided according to their chlorination degree. Until recently, the most common strategy implemented for their analysis was GC-ECNI-LRMS, with the main disadvantage being the high dependence of the response to the chlorination degree and the incapability of analysing LCCPs. In this work, we developed a method based on liquid chromatography coupled with electrospray ionisation-Orbitrap mass spectrometry (LC-ESI-HRMS) to expand the analysis capabilities of CPs. Although the different physico-chemical properties of CPs have led to compromises on the choice of analytical parameters, the addition of a mixture of DCM/ACN post-column with appropriate LC-ESI(-)-HRMS parameters enabled optimal and simultaneous detection of SCCPs, MCCPs and LCCPs from 10 to 36 carbons in one single injection. The combination of both the optimised LC-ESI parameters and the high resolution of the mass spectrometer (R = 140,000 @200 m/z) allowed separation of CPs signals of interest from unwanted halogenated ones, leading to minimum interferences in the detection. The optimised method was then successfully applied to the characterization of three types of vegetable oil, which were mostly contaminated with MCCPs. Additionally, the implementation of the LCHRMS strategy enabled the identification of highly chlorinated LCCPs in edible oil for the first time at dozens of ng g-1 lw, which demonstrates the need of such comprehensive methods to expand the knowledge about CPs occurrence in food and environmental matrices.


Assuntos
Cromatografia Líquida , Monitoramento Ambiental/métodos , Análise de Alimentos/métodos , Hidrocarbonetos Clorados/análise , Espectrometria de Massas , Parafina/análise
12.
Chemosphere ; 244: 125574, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32050349

RESUMO

Chlorinated paraffins (CPs) are high production volume chemicals of which some show resistance to environmental degradation, long-rang transport, bioaccumulation and toxicity potential. Information regarding their presence in humans is limited, including their human bioaccumulation potential. The present study aimed to evaluate CP levels in human serum from Australia in order to better understand their exposure and current pollution status as well as trends associated with age and time between 2004 and 2015. For this, we selected a male sub-group of the Australian population under 60 years old (n = 16 pools, total 1600 serum samples). While long-chain CP (C18-20) and most short-chain CP (C10-13, SCCPs) levels were below method detection limits (MDL), medium-chain CPs (C14-17, MCCPs) were found in most serum samples (detection frequency 94%) as well as CPs with a carbon chain length of nine (detection frequency 76%). The levels of ΣSCCPs and ΣMCCPs ranged from

Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/metabolismo , Hidrocarbonetos Clorados/sangue , Parafina/metabolismo , Austrália , Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Humanos , Hidrocarbonetos Clorados/análise , Pessoa de Meia-Idade , Parafina/análise
13.
Environ Sci Technol ; 54(5): 2753-2762, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32036653

RESUMO

Very-short, short-, medium-, and long-chain chlorinated paraffins (vSCCPs, SCCPs, MCCPs, and LCCPs, respectively) were analyzed in different tissues of the terrestrial short-tailed mamushi (Gloydius brevicaudus) and the semi-aquatic red-backed rat snake (Elaphe rufodorsata) from the Yangtze River Delta, China. The total CP concentrations in liver, muscle, and adipose tissues in the two snake species were in the range of 2500-24 000, 4900-48 000, and 12-630 ng/g lw, respectively. Tissue burdens indicated that vSCCPs (C6-9) and SCCPs (C10-13) preferentially distributed to snake liver, while adipose was an important storage site and sink of MCCPs (C14-17) and LCCPs (C>18). On a lipid weight basis, vSCCPs and SCCPs were found in highest concentrations in red-backed rat snake liver and MCCPs and LCCPs in muscle, whereas for short-tailed mamushi, all CP groups were predominant in muscle, probably reflecting ecosystem/food web differences. Moreover, vSCCPs, SCCPs, MCCPs, and LCCPs were found to be biomagnified from black-spotted frogs to red-backed rat snakes with mean (maximum) biomagnification factors of 2.2 (3.4), 1.9 (3.7), 1.8 (2.8), and 1.7 (4.5), respectively. This is the first field study of biomagnification potential involving vSCCPs and LCCPs and highlights the need to include all CPs in studies.


Assuntos
Hidrocarbonetos Clorados , Parafina , Animais , Bioacumulação , China , Ecossistema , Monitoramento Ambiental , Rios , Serpentes , Distribuição Tecidual
14.
Chemosphere ; 247: 125855, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31935577

RESUMO

To preliminarily investigate the occurrence, spatial distributions, homolog compositions, and ecological risks of chlorinated paraffins (CPs) in Yunnan, China, 110 soil samples were collected from an area part of Yunnan, representative of the whole Yunnan area, where had similar characteristics to most parts of Yunnan and 22 pooled soil samples were analyzed for 50 CP congener groups (C9-17Cl5-10). The chlorinated nonane paraffin (C9-CP), short chain (SCCP), and medium chain chlorinated paraffin (MCCP) concentrations in soil samples were 8-109 ng/g (average 39 ng/g), 79-948 ng/g (average 348 ng/g), and 20-1206 ng/g (average 229 ng/g), respectively. The C9-CP homologs contributed 5%-16% of the C9-13-CP concentrations in soils. No significant correlation was found between CP concentrations and the total organic carbon content (P > 0.05). The CP levels in soils from Yunnan were at a medium level compared with those in other areas worldwide. Human activity and atmosphere deposition would influence the levels and spatial distributions of CPs in this area. The concentrations of CPs in east area were higher than those in west area. C10Cl6-7 were the major SCCP congeners and C14Cl6-7 were the major MCCP congeners. Principal component analysis indicated that SCCPs and MCCPs came from different sources. A preliminary risk assessment indicated that these concentrations of CPs in soil from Yunnan do not pose a significant ecological risk for soil organisms.


Assuntos
Hidrocarbonetos Clorados/análise , Parafina/análise , Solo/química , Alcanos/química , China , Monitoramento Ambiental/métodos , Humanos , Parafina/química , Medição de Risco
15.
Environ Pollut ; 259: 113853, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31923813

RESUMO

To highlight the levels and distributions and to assess the risk of human exposure of chlorinated paraffins (CPs) in PM2.5 in China, the concentrations and homologue patterns of short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) in PM2.5 from 10 cities in China were studied in 2013 and 2014. The mean concentrations of ΣSCCPs and ΣMCCPs were 19.9 ± 41.1 ng m-3 and 15.6 ± 18.6 ng m-3, respectively. Unexpectedly, the highest pollution levels occurred in two central cities (Xinxiang and Taiyuan) rather than in well-known eastern megacities such as Beijing, Nanjing, Shanghai, and Guangzhou. By comparing with earlier research, it has indicated the trend of CPs industry shifting from large eastern cities to small and medium-sized cities in central China to some extent. In addition, the composition pattern of SCCPs demonstrated an obviously differences from previous studies, with C11 and Cl7 predominating and accounting for 45.1% and 24.9%, respectively. Meanwhile, the ratio of MCCPs/SCCPs in most cities was less than 1.00 except for Guangzhou (1.92), Shanghai (1.29), and Taiyuan (1.11). Combined with the results of correlation analysis and principal component analysis, the observed pollution characteristics of CPs in PM2.5 had similar sources, which were more influenced by the ratio of MCCPs/SCCPs than by organic carbon, elemental carbon, temperature, population, and gross domestic product. Overall, the composition of CPs reflected the characteristics of local industrial production and consumption, and also implied efforts of Chinese enterprises to reduce the content of short carbon groups of CPs production. The CPs mainly deposited in head airways during the process of entering the human respiratory system. However, at the present levels, there was no significant carcinogenic effect for human health.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Clorados , Indústrias , Parafina/análise , Material Particulado , Pequim , China , Cidades , Indústrias/tendências , Material Particulado/química , Análise Espaço-Temporal
16.
Environ Sci Technol ; 54(2): 996-1004, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31829571

RESUMO

Short-chain chlorinated paraffins (SCCPs), a class of ubiquitous pollutants, are considered to be embryotoxic and teratogenic. However, little is known regarding the bioactivity and mechanisms at environmentally relevant concentrations at the embryonic period. Here, a concentration-dependent reduced transcriptomic approach was used to evaluate the environmental dose (<100 ppb) effects of nine SCCP congeners and eight commercial mixtures on zebrafish embryos at 8 hpf. After 24 h of exposure, the overall biological potency of all the SCCPs, in terms of interference with 20% of the differentially expressed genes (PODDEG20), in zebrafish embryos ranged from 0.83 to 67.61 ppb. C10H14Cl8 (PODGO20 = 3.80 ppb) and C10-13 51.5% Cl (PODGO20 = 3.31 ppb) exhibited the strongest interference with biological processes compared to other SCCP homologs and mixtures, respectively. The most sensitive early molecular responses induced by SCCPs were associated with pathways of genetic damage, energy metabolite interference, and metal ion binding. Furthermore, the carbon number was positively correlated with the transcriptomic potency (PODGO20) of SCCP congeners (with chlorine content > 60%) (p = 0.038), and the chlorine content of SCCP congeners affected the bioactivity associated with genotoxic pathways. The concentration-dependent reduced transcriptomic approach significantly improved the understanding of the ecological risk of environmental contaminants at early life stages.


Assuntos
Hidrocarbonetos Clorados , Parafina , Animais , China , Monitoramento Ambiental , Transcriptoma , Peixe-Zebra
17.
J Chromatogr A ; 1610: 460550, 2020 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31547958

RESUMO

As short-chain chlorinated paraffins (SCCPs) are listed on several monitoring programs, validated methods are essential. However, their complexity and the lack of commercially available certified reference materials (RMs) hinder a proper validation of methods. Instead, one method is usually 'validated' by evaluating performances and results of spiked materials with that of one other method, which could easily lead to unreliable results. This study evaluated four analytical methods with different principles (i.e. comprehensive two dimensional GC coupled to a micro electron capture detector, developed for this study, chloride enhanced atmospheric pressure chemical ionization triple quadrupole time of flight MS (APCI-QToF-HRMS), GC coupled to an electron capture negative ion low resolution MS (GC-ECNI-LRMS) and carbon skeleton GC-MS), investigated the comparability in SCCP determination in spiked and naturally contaminated samples and determined SCCP amounts in candidate RMs for possible certification. The results cast doubt on the use of the most commonly applied method (i.e. GC-ECNI-LRMS), as well as using spiked materials for method validation. The APCI-QToF-HRMS method was found most promising as it achieves the required MS resolution (>21,000), is relatively fast and can detect also other CPs. The suitable identified SCCP levels in the candidate RMs and the agreement in results between the methods bring the first certification of a RM for SCCPs within reach.


Assuntos
Poluentes Ambientais/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Gasosa-Espectrometria de Massas/normas , Hidrocarbonetos Clorados/análise , Parafina/análise , Monitoramento Ambiental , Poluentes Ambientais/química , Hidrocarbonetos Clorados/química , Parafina/química , Reprodutibilidade dos Testes
18.
Chemosphere ; 244: 125531, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31821924

RESUMO

Wastes containing short-chain chlorinated paraffins (SCCPs) at concentrations above the Basel Convention low persistent organic pollutant content (LPC) values must be destroyed or irreversibly transformed in an environmentally-sound manner. Here, we developed a novel liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MSMS) method for determining the concentrations of SCCPs in mixed plastic wastes. Major SCCP homologues were identified with good separation and peak width by using a low-hydrophobicity cyano-propyl column and a mobile phase consisting of water and methanol containing ammonium acetate. Precursor ion peaks corresponding to the formation of stable SCCP homologue-adducts were observed, followed by two intense product ion peaks corresponding to separation of the adduct into acetate and the homologue. The formulation of a novel calibration standard with known SCCP homologue percentage composition supported the development of our novel mass spectrometric technique. The results obtained with the LC-ESI-MSMS system were quantitatively and qualitatively comparable with those obtained with a high-resolution mass spectrometry (HRMS) coupled to gas chromatography (GC) system. Homologue concentrations determined by LC-ESI-MSMS were significantly correlated with those determined by GC-HRMS in samples of commercial chlorinated paraffin mixture and mixed plastic waste, respectively. As a complementary technique to the highly accurate, but less versatile GC-HRMS approaches, the SCCP analysis by LC-ESI-MSMS is a practical way to identify mixed plastic wastes containing SCCPs at concentrations higher than the Basel Convention's LPC value.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Hidrocarbonetos Clorados/análise , Parafina/análise , Plásticos/análise , Cromatografia Líquida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Parafina/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
19.
Environ Sci Technol ; 54(2): 938-946, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31736300

RESUMO

Chlorinated paraffins (CPs) are chemicals with high production volumes that can accumulate at high levels in general populations. The pharmacokinetics of CPs as pollutants is unknown, and there is no evidence that the medium chain chlorinated paraffins (MCCPs) and long chain chlorinated paraffins (LCCPs) are safe replacements for short chain chlorinated paraffins (SCCPs). In this study, SCCPs, MCCPs, and LCCPs were first in vivo and in vitro exposed to rat and liver microsomes, respectively. Toxicokinetics of these compounds were assessed and used to establish the corresponding physiologically based pharmacokinetic (PBPK) models in rats. More than 90% of ingested CPs were deposited in the liver and fat, and the compounds were extremely resistant to metabolism and mostly eliminated via biliary excretion. Then, humans' external and internal exposures to CPs were investigated for one year in Shenzhen, South China. The results were used to calibrate the key parameters for the establishment of a PBPK model in humans. In the PBPK models of rats and humans, the rate of biliary excretion had the greatest influence on the accumulated levels and half-lives of CPs. The body half-lives of human were estimated to be 5.1, 1.2, and 0.6 years for SCCPs, MCCPs, and LCCPs, respectively, suggesting the high accumulation of SCCPs in humans compared to other CPs.


Assuntos
Eliminação Hepatobiliar , Hidrocarbonetos Clorados , Animais , China , Monitoramento Ambiental , Humanos , Parafina , Ratos
20.
Chemosphere ; 244: 125393, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31790997

RESUMO

Dietary intake is the major route for the exposure of residents to short-chain chlorinated paraffins (SCCPs). SCCPs are classified as persistent organic pollutants (POPs) by the Stockholm Convention since May 2017. This study assessed the general population's dietary exposure to SCCPs through supermarket products. Five food categories, which included 40 food species, were collected from five supermarkets in April 2019. The SCCP concentrations in all food matrices varied between 58.6 and 1977 ng g-1 dry weight (dw), with the average and standard deviation (SD) value of 301 ± 379 ng g-1 dw. Generally, the SCCP concentrations in animal-origin food matrices were higher than those in plant-origin food matrices. The C10Cl7 congeners were predominant among the congener groups of SCCPs. The proportion of C10 congeners in the animal-origin food samples (29.8%) was lower than that in the plant-origin food samples (39.7%), and the C13 congeners showed a contrasting result. The estimated daily intake (EDI) of SCCPs through dietary intake for the residents was 3109 ng kg-1 day-1, which is much lower than the standards of European Food Safety Authority (10 mg kg-1 day-1) for SCCPs. Risk assessment based on the supermarket foods indicated that SCCP exposure through dietary intake does not cause adverse effects to human health according to the margin of exposure (MOE).


Assuntos
Exposição Dietética/estatística & dados numéricos , Monitoramento Ambiental , Poluentes Ambientais/análise , Parafina/análise , Ração Animal , China , Contaminação de Alimentos/análise , Contaminação de Alimentos/estatística & dados numéricos , Humanos , Hidrocarbonetos Clorados/análise , Medição de Risco
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