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1.
Sci Total Environ ; 945: 173988, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38889819

RESUMO

Monitoring only 16 priority PAHs (Pri-PAHs) may greatly underestimate the pollutant load and toxicity of polycyclic aromatic compounds (PACs) in aquatic environments. There is an urgent need to reevaluate the list of priority PACs. To determine which PACs deserve priority monitoring, the occurrence, sources, and toxicity of 78 PACs, including 24 parent PAHs (Par-PAHs), 49 alkylated PAHs (Alk-PAHs), 3 oxygenated PAHs (OPAHs), carbazole, and dibenzothiophene were investigated for the first time in Lake Chaohu sediments, China. Concentrations of ∑Par-PAHs, ∑Alk-PAHs, and ∑OPAHs ranged from 35 to 165, 3.4-26, and 7.7-26 ng g-1, respectively. Concentrations of 16 Pri-PAHs have decreased by 1-2 orders of magnitude compared to a decade ago, owing to the effective implementation of PAHs emission control measures. Comparisons with the sediment quality guidelines indicated that 16 Pri-PAHs have negligible adverse effects on benthic organisms. Positive matrix factorization (PMF) model results showed that coal combustion was the major source of PACs (accounting for 23.5 %), followed by traffic emissions (23.4 %), petroleum volatilization (21.9 %), wood/biomass combustion (18.2 %), and biological/microbial transformation (13.1 %). The toxicity of PACs was assessed by calculating the BaP toxic equivalent concentrations (TEQBaP) and toxic units. It was found that Par-PAHs were the predominant toxic substances. In addition, monomethyl-BaPs, OPAHs, BeP, and 7,12-DMBaA should be prioritized for monitoring due to their noticeable contributions to overall toxicity. The contributions of different sources to the toxicity of PACs were determined based on PMF model results and TEQBaP values, which revealed that combustion sources mainly contributed to the comprehensive toxicity of PACs in Lake Chaohu sediments.

2.
Environ Sci Pollut Res Int ; 31(14): 22012-22023, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38400976

RESUMO

Are the residues of organochlorine pesticides (OCPs) in freshwater in China still of concern after prohibition and restriction for decades? The scarcity of monitoring data on OCPs in freshwater in China over the past few years has hampered understanding of this issue. In this study, water and suspended particulate matter (SPM) samples were collected from the middle reach of the Huai River for OCP analyses. Residues of ∑OCPs in water and SPM ranged from ND to 8.6 ng L-1 and 0.50 to 179 ng L-1, with mean concentrations of 1.7 ± 1.3 ng L-1 and 6.1 ± 31 ng L-1, respectively. ∑HCHs (α-, ß-, γ-, and δ-HCH) and ∑HEPTs (heptachlor and heptachlor epoxide) were the most predominant pesticides in the dissolved phase and SPM, respectively, accounting for 43 ± 35% and 27 ± 29% of ∑OCPs. HCHs and heptachlor epoxide mainly existed in the dissolved phase, while heptachlor mainly existed in SPM. The isomeric composition pattern of HCHs in water differed from that in SPM. Briefly, ß-HCH dominated in water, while δ-HCH dominated in SPM. However, the composition pattern of DDT and its metabolites in water was similar to that in SPM. o,p'-DDD and p,p'-DDE dominated in both water and SPM. The ratios of α-/γ-HCH and (DDD + DDE)/DDTs indicated that HCHs and DDTs were mainly derived from historical residues. Risk assessments indicated that OCPs may not pose carcinogenic and non-carcinogenic risks to residents.


Assuntos
Osso e Ossos/anormalidades , Nanismo , Hexaclorocicloexano , Hidrocarbonetos Clorados , Deformidades Congênitas dos Membros , Lordose , Praguicidas , Humanos , Rios , Heptacloro Epóxido , Heptacloro , Mitotano , Água , China
3.
Ecotoxicol Environ Saf ; 263: 115286, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37481858

RESUMO

The comprehensive understanding of PCBs' fate has been impeded by the lack of simultaneous monitoring of PCBs in multiple environmental media in the background areas, which were considered long-term sinks for highly chlorinated PCBs. To address this gap, this study analyzed soils, willow tree barks, water, suspended particulate matter (SPM), and sediment samples collected from the middle reach of the Huaihe River in China for 27 PCBs. The results showed that the levels of ∑27PCBs in the soils were comparable to or lower than the background values worldwide. There were no significant correlations between organic matter and ∑27PCB concentrations in the soils and sediments. Additionally, the contamination of dioxin-like PCBs in the aquatic environment of the study area deserves more attention than in the soils. Applying the level III fugacity model to PCB 52, 77, 101, and 114 revealed that the soil was the primary reservoir, and air-soil exchange was the dominant intermedia transfer process, followed by air-water exchange. Furthermore, simulated results of air-soil and air-water diffusion were compared with those calculated from the field concentrations to predict the potential environmental behaviors of PCBs. Results indicated that the studied river would be a "secondary source" for PCB 52, 77, and 101. However, PCB 52, 77, 101, and 114 would continue to transfer from the air to the soil. This study combines multimedia field measurements and the fugacity model, providing a novel approach to predicting the potential environmental behaviors of PCBs.


Assuntos
Bifenilos Policlorados , Bifenilos Policlorados/análise , Multimídia , Monitoramento Ambiental/métodos , Água , Solo
4.
Environ Sci Pollut Res Int ; 30(23): 64254-64264, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37069373

RESUMO

This is the first comprehensive report on antibiotics in the Huai River, a major Chinese river. To illuminate the concentrations, prioritization, spatial distributions, sources, and ecological risks of antibiotics, surface water samples were collected and three types of most widely used antibiotics (16 sulfonamides, 8 tetracyclines, and 14 quinolones) were analyzed. The results indicated that concentrations of ∑quinolones (86 ± 31 ng/L) > ∑tetracyclines (20 ± 13 ng/L) > ∑sulfonamides (11 ± 3.7 ng/L). Oxolinic acid (OXA), cinoxacin(CINX), norfloxacin (NFX), and methacycline (MTC) were the priority antibiotics with mean concentrations > or close to 10 ng/L, however, they were rarely included as target compounds in most previous Chinese investigations. Different spatial distributions of antibiotics were discovered across three reaches separated by two sluices, demonstrating that the sluices may impact antibiotic dissemination. According to the results of the source analysis, the aquaculture industry was the major source of observed antibiotics (49%), followed by livestock & poultry farming (26%) and mixed sources (25%). Because commercial fishing in the Huai River has been prohibited, the aquaculture industry will expand in the next years, and antibiotic contamination caused by the aquaculture industry deserves more attention. The risk quotients were calculated by comparing observed antibiotics to predicted no-effect concentrations, and the results showed that observed antibiotics posed negligible or low integrated risks for Green algae, and medium or low integrated risks for Daphnia magna.


Assuntos
Quinolonas , Poluentes Químicos da Água , Antibacterianos/análise , Aquicultura , China , Monitoramento Ambiental/métodos , Quinolonas/análise , Medição de Risco , Rios , Sulfanilamida , Sulfonamidas/análise , Tetraciclinas/análise , Poluentes Químicos da Água/análise
5.
Sci Total Environ ; 879: 163045, 2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-36963675

RESUMO

Polycyclic aromatic compounds (PACs) are important hazardous air pollutants in China due to the country's coal-dominant energy structure. In order to reveal the pollution characteristics, sources, toxicity, and pollution historical trends of PACs in the atmosphere of the middle reach of the Huaihe River (MRHR), a large-scale coal-fired power base of China, tree barks and tree cores were collected and employed as passive air samplers and historical trend recorders, and 76 PACs were identified for the first time. ΣPACs in tree barks ranged from 170 to 3800 ng g-1 (mean = 700 ± 720 ng g-1), with the high concentrations observed mainly in the coal-mining and coal-bearing area. 16 priority PAHs (PriPAHs) were the predominant substances and accounted for 59 ± 8.3 % of ΣPACs. The combustion of coal and fuel oil was the most significant source of PACs, accounting for 43 % of ΣPACs, followed by the combustion of biomass (30 %) and non-combustion sources (27 %). Based on a bark-air partitioning model, volumetric air concentrations for ΣPACs were calculated to be 450-11,000 ng m-3 (mean = 1600 ± 2000 ng m-3). The BaP-toxic equivalent concentrations (TEQBaP) of ΣPACs (mean = 9.7 ± 15 ng m-3) were significantly higher than the Chinese guideline (1 ng m-3) and were mostly caused by coal & fuel oil combustion (55 ± 13 %). High molecular weight PACs were detected in lower percentages in tree cores than in tree barks, indicating that PACs in the particle phase were difficult to enter the tree core. Major PACs decreased in tree core samples between 2000 and 2020 as pollution control efforts improved, however, some PACs showed different trends when influenced by point sources.


Assuntos
Poluentes Atmosféricos , Óleos Combustíveis , Hidrocarbonetos Policíclicos Aromáticos , Compostos Policíclicos , Compostos Policíclicos/análise , Carvão Mineral/análise , Casca de Planta/química , Árvores , Poluentes Atmosféricos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , China , Monitoramento Ambiental
6.
Ecotoxicol Environ Saf ; 250: 114479, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36603484

RESUMO

The Dashan Region was a Se-rich region of China. In this study, 131 residents' human hair samples were collected. The concentrations of Se and toxic metals were analyzed, and the health risk was estimated using the concentration data. Cd and As concentrations were significantly higher than in East China. Se and most toxic metal concentrations increased with age (except for the aged people). Furthermore, gender and smoking habits might have a significant impact on toxic metals and Se levels. Multivariable statistics analysis revealed that Se and toxic metals primarily originate in the environment and are then transferred to the human body via the food chain. Dietary habits had an effect on the Se and As concentrations in hair, according to the results of stable isotope analysis. To assess detoxification ability, the Se/ toxic metal molar ratio was used as an indicator. The results demonstrated that the antagonistic effect of Se and Cd, As, Cr, and Hg (molar ratio > 1) could effectively protect residents in the study area from Cd and As pollution in daily life.


Assuntos
Mercúrio , Metais Pesados , Selênio , Humanos , Idoso , Selênio/análise , Cádmio/toxicidade , Cádmio/análise , Mercúrio/análise , China , Cabelo/química , Metais Pesados/toxicidade , Metais Pesados/análise
8.
Adv Ther ; 39(5): 1976-1992, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35246820

RESUMO

INTRODUCTION: Many treatment regimens have been evaluated in transplant-ineligible (TIE) patients with newly diagnosed multiple myeloma (NDMM). The objective of this study was to compare the efficacy of relevant therapies for the treatment of TIE patients with NDMM. METHODS: Progression-free survival (PFS) and overall survival (OS) from large randomised controlled trials (RCTs) evaluating different treatment options for TIE patients with NDMM were compared in a network meta-analysis (NMA). The NMA includes recent primary and long-term OS readouts from SWOG S0777, ENDURANCE, MAIA, and ALCYONE. Relevant trials were identified through a systematic literature review. Relative efficacy measures (i.e., hazard ratios [HRs] for PFS and OS) were extracted and synthesised in random-effects NMAs. RESULTS: A total of 122 publications describing 45 unique RCTs was identified. Continuous lenalidomide/dexamethasone (Rd) was selected as the referent comparator. Daratumumab-containing treatments (daratumumab/lenalidomide/dexamethasone [D-Rd], daratumumab/bortezomib/melphalan/prednisone [D-VMP]) and bortezomib/lenalidomide/dexamethasone (VRd) had the highest probabilities of being more effective than Rd continuous for PFS (HR: D-Rd, 0.53; D-VMP, 0.57, VRd, 0.77) and OS (HR: D-Rd, 0.68; VRd, 0.77, D-VMP, 0.78). D-Rd had the highest chance of being ranked as the most effective treatment with respect to PFS and OS. Results using a smaller network focusing on only those regimens that are relevant in Europe were consistent with the primary analysis. CONCLUSIONS: These comparative effectiveness data may help inform treatment selection in TIE patients with NDMM.


Assuntos
Mieloma Múltiplo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bortezomib/uso terapêutico , Dexametasona/uso terapêutico , Humanos , Lenalidomida/uso terapêutico , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/tratamento farmacológico , Metanálise em Rede , Resultado do Tratamento
9.
Chemosphere ; 296: 134020, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35216981

RESUMO

Distributions, souces, ecological risks as well as environmental behaviors of 20 organochlorine pesticides (OCPs) in riparian soils and sediments of the middle reach of the Huaihe River, a traditional agricultural area of China, were investigated. ∑OCPs in riparian soils and sediments were 1.8-63 ng g-1 (mean = 19 ± 12 ng g-1) and 1.2-9.9 ng g-1 (mean = 3.0 ± 1.8 ng g-1), respectively. HCHs were the dominant OCPs in both soils and sediments, while high concentrations of ∑HEPTs and ∑DDTs were also detected in some soils and sediments. No correlations were found between concentrations of OCPs and organic matter contents in both soils and sediments. Based on the source analysis, most OCPs in the riparian soils were mainly from historical residues, such as historical usage of technical HCH, DDT, chlordane and endosulfan. OCPs in sediments were influenced not only by surface runoff by also by other factors, e.g. in-situ contamination (DDT-containing antifouling paints in ships) and/or hydraulic transport from some tributaries. Some never-used OCPs, such as heptachlor and aldrin, were widely detected in soils and sediments. This might be attributed to some unknown usages or long-range atmospheric transport of them from other source regions. Ecological risk analysis suggested that DDTs and HCHs in soils would not lead to an adverse effect on soil ecological environment as well as agricultural production, and OCP residues in sediments also would not pose a threat to the sediment-dwelling organisms.


Assuntos
Hidrocarbonetos Clorados , Praguicidas , Poluentes Químicos da Água , China , DDT/análise , Monitoramento Ambiental , Sedimentos Geológicos/química , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Rios/química , Solo , Poluentes Químicos da Água/análise
10.
Water Environ Res ; 93(11): 2795-2806, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34486191

RESUMO

The present study sought to determine the systematic pollution status of the heavy metals (HMs) found in the sediment around Taihu Lake, China. The concentrations and speciations of the HMs in the sediment were measured. The Ni and Cr concentrations exceeded the probable effect level (PEL), while the concentrations of the other HMs (except Hg) were between the threshold effect level and the PEL. The enrichment factor values for all HMs indicated slight enrichment. The geoaccumulation index revealed that the HMs represented light pollution, while the average contaminant factor value of the HMs indicated moderate pollution. The ecological risk factor value indicated a medium ecological risk, with Cd and Hg being associated with a high and considerable potential ecological risk, respectively. The ecological risk index indicated that the ecological risk posed by the HMs was high. The contamination degree revealed a moderate level of metal pollution, while the pollution load index indicated a heavy pollution level. The extractable proportion of the HMs (except for Cr and As) exceeded 50%. In the case of Cd, the exchangeable proportion was 51.11%, which indicated it to be extremely unstable. PRACTITIONER POINTS: Heavy metals (except for Cr and As) have a high potential ecological risk. All selected heavy metals implying varying degrees of instability. Cd was the most serious pollutant based on the Igeo, Cf and EF analyses.


Assuntos
Metais Pesados , Poluentes Químicos da Água , China , Monitoramento Ambiental , Sedimentos Geológicos , Lagos , Metais Pesados/análise , Medição de Risco , Poluentes Químicos da Água/análise
11.
Ecotoxicol Environ Saf ; 214: 112095, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33667735

RESUMO

In this study, urban stream sediment samples were collected in the Suzhou Industrial Park (SIP), one of the earliest national demonstration eco-industrial parks of China. PAHs were analyzed in these sediments, and concentrations of total PAHs were 180-81,000 ng g-1 (5700 ± 14,000 ng g-1). Medium molecular weight (4- ring) PAHs were predominant (42 ± 12%), followed by high molecular weight (5- and 6- ring) PAHs (31 ± 10%). No correlation was found between concentrations of PAHs and land uses of SIP in this study. Diagnostic ratios and a positive matrix factorization (PMF) model indicated that coal/biomass combustion might be the primary PAH source (61%), followed by non-combustion sources (21%) and vehicular emission (18%). According to the spatial analysis, PAHs in the sediments of SIP might be mainly associated with the coal/biomass combustion in the northeast industrial zone. Residential & commercial activities seem not to be the major causes of PAH contamination. Total PAH toxic equivalent concentrations, effect range low/effect range median values, and mean effects range-median quotient all showed that PAHs were present at a low toxicity risk level in most regions of the SIP. However, vigilance is required at some sampling sites with extremely high PAH concentrations or high mean effects range-median quotient.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , China , Carvão Mineral/análise , Monitoramento Ambiental , Sedimentos Geológicos , Indústrias , Medição de Risco , Rios , Emissões de Veículos/análise
12.
Bull Environ Contam Toxicol ; 105(2): 230-236, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32671410

RESUMO

Fifty-four surface sediments from the typical coal mining area were analyzed for pristane, phytane and C8-C40 n-alkanes using gas chromatography-mass spectrometry (GC-MS). The spatial distribution, homolog profiles and source apportionment of aliphatic hydrocarbons were investigated. Bimodal distribution pattern, centered at C16-C20 and C27-C33 n-alkanes, were observed in all sediment samples with an obvious dominance of low molecular weight homologues. Principal component analysis-multiple linear regression (PCA-MLR) was used to predict the contributions of different sources. The result implied that natural input was the main source, contribution of which accounted for 60.8%, and the contributions of different sources were estimated as follow: 21.8% for terrestrial higher plants, 24.1% for algae and photosynthetic bacteria, 14.9% for submerged/floating macrophytes, 23.5% for fossil fuel combustion and 15.7% for petroleum hydrocarbons. Moreover, relatively high median concentrations of fossil fuel combustion were observed in Shou County and Fengtai County, indicating the high contribution of fossil fuel combustion in these two areas.


Assuntos
Minas de Carvão , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Hidrocarbonetos/análise , Petróleo/análise , Alcanos/análise , China , Diterpenos/análise , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos Policíclicos Aromáticos/análise , Análise de Componente Principal , Terpenos/análise , Poluentes Químicos da Água/análise
13.
Chemosphere ; 258: 127359, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32544807

RESUMO

From November 2013 to March 2014, air samples were collected in the Antarctic marginal seas during the 30th Chinese Antarctic research expedition. Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were analyzed in these samples. The mean concentrations were observed for hexachlorobenzene (HCB) >ΣPCBs >Σhexachlorocyclohexanes(HCHs) >Σdichlorodiphenyltrichloroethane(DDTs)>Σchlordanes. High levels of HCB were found near east Antarctica and in the Ross Sea, reflecting the re-emission of HCB from environmental reservoirs of these regions. Parent DDTs (p,p'- and o,p'-DDT) were rarely detected, suggesting that atmospheric DDT was predominantly influencedby weathered DDT from some secondarysources. However, fresh inputs of DDTs could not be excluded because there were still some samples with high proportions of parent DDTs. HCHs only were detected in the South Indian Ocean (near Australia), andthis result might be related to the intense emissions of HCHs from southern Australia. Ratios of trans-chlordane/cis-chlordanein most samples were lower than that in technical chlordane, reflecting the main influence of weathered chlordane. High levels of ΣPCBs were found in the Ross Sea, suggesting an intense re-emission of PCBs. Furthermore, atmospheric PCBs near the Antarctic Peninsula were also relatively high, this finding might be attributed to the emissions of PCBs from nearby Antarctic research stations. Comparing with the Arctic, transport of OCPs and PCBs towards Antarctica is more difficult. The Antarctic marginal seas would act as both barriers and "buffer zones"during the transportation processes.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Movimentos do Ar , Regiões Antárticas , Oceano Índico , Austrália do Sul
14.
Environ Sci Pollut Res Int ; 26(34): 35094-35106, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31679141

RESUMO

The surface soils were collected from four areas in the Yellow River Delta (YRD), including three functional areas in the natural reserve of the YRD (the core area, buffer area, and experimental area) and a neighboring area of the natural reserve. The total concentrations, speciations, contamination status, and health risk assessments of the mercury (Hg) and arsenic (As) in surface soils of the YRD were investigated. The average Hg concentration was about three times that of the background value, while As was just slightly higher than the background. Hg levels in the sites of experimental area were significantly higher than those in the core area and buffer area, which was consistent with the human activity intensities of the three functional areas. However, no significant differences of As levels were observed across different areas. According to the sequential extraction experiments, only less than 5% of Hg and As were associated with the exchangeable fraction, while over 80% of them were found in the residual fraction, indicating low mobility and bioavailability of both Hg and As. The soil contamination status assessments suggested a "good state," and the health risk assessments indicated a "low risk" of Hg and As in the soils of YRD.


Assuntos
Arsênio/análise , Monitoramento Ambiental , Mercúrio/análise , Poluentes do Solo/análise , China , Humanos , Medição de Risco , Rios , Solo
15.
Arch Environ Contam Toxicol ; 77(4): 594-604, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31388704

RESUMO

A total of 39 lower brominated PBDE congeners in surface soils from the Yellow River Delta Natural Reserve (YRDNR) were analyzed in the present study. The total concentrations of PBDEs (ΣPBDEs) ranged from "not detected" to 0.732 ng g-1, with a mean concentration of 0.142 ng g-1. The concentrations of the ΣPBDEs displayed no correlation with the content of the total organic carbon in the YRDNR. The ΣPBDEs concentrations in the Experimental Area were significantly higher than that of the Buffer Area and Core Area, and ΣPBDEs in soils in the North were lower than that of the South. PentaBDEs and HexaBDEs were the most abundant homologues, and the occurrence of PBDEs in the YRDNR may be attributed to the debromination and long range transport of DecaBDEs. Even though the cancer risk and mass inventory of PBDEs in the present study area were estimated to be very low, due to the widespread presence of PBDEs and the particularity of the natural reserve, vigilance should not be let up on the issue of environmental contamination caused by these compounds despite the gradual phase out of their commercial products in the world.


Assuntos
Éteres Difenil Halogenados/análise , Poluentes do Solo/análise , Carcinógenos Ambientais/análise , Carcinógenos Ambientais/toxicidade , China , Conservação dos Recursos Naturais , Monitoramento Ambiental , Retardadores de Chama/análise , Éteres Difenil Halogenados/toxicidade , Humanos , Medição de Risco , Poluentes do Solo/toxicidade
16.
Bull Environ Contam Toxicol ; 102(6): 843-847, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30993357

RESUMO

A total of 28 PCB congeners were determined using gas chromatography-mass spectrometry (GC-MS) in 46 surface soils collected from the Yellow River Delta Natural Reserve (YRDNR) and its adjacent area, China. The total concentrations of PCBs in the YRDNR ranged from 0.149 to 4.32 ng/g, with a mean concentration of 0.802 ng/g. Light PCB congeners predominated in the present research area, which may be attributed to the atmospheric transportation and were also associated with the recent contamination of unintentionally produced PCBs from industrial processes. In addition, PCB 126 and PCB 169 were found to be the major toxicity contributors of dioxin-like PCBs in the YRDNR, which should require special focus.


Assuntos
Bifenilos Policlorados/análise , Rios/química , Poluentes do Solo/análise , Solo/química , China , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas , Bifenilos Policlorados/química , Medição de Risco , Poluentes do Solo/química
17.
Mar Pollut Bull ; 140: 388-394, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30803658

RESUMO

Heavy metal pollution is a serious environmental problem. Up to date, research regarding distribution, accumulation and potential risk assessment of metals in aquatic organisms in Laizhou Bay, China is scarce. This study aims to investigate metals in aquatic organisms in this region. The results demonstrated that great variability of metals content occurred among species and sampling locations. Fe was the most abundant metal, followed by Zn, Mn, Cu, Ni, Cr, Cd and Pb. Overall, shellfish and crab displayed high enrichment ability compared with fish and shrimp. There was no significant correlation between metals and samples weight, δ13C and δ15N values. Principal component analysis (PCA) indicated that metals in samples were mainly derived from anthropogenic activities. Health risk of metals was evaluated on the basis of estimated daily intake (EDI) and target hazard quotient (THQ) values. The results indicated that metals in studied seafood had no significant risks for ordinary consumers.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Baías/química , Monitoramento Ambiental/métodos , Metais Pesados/análise , Poluentes Químicos da Água/análise , Animais , China , Metais Pesados/toxicidade , Medição de Risco , Frutos do Mar/análise , Poluentes Químicos da Água/toxicidade
18.
Mar Pollut Bull ; 135: 47-54, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30301061

RESUMO

A sediment core, spanning from the year 1925 ±â€¯3.03 to 2012, was collected for analyzing historical distribution of mercury (Hg) in the Old Yellow River Estuary (OYRE), China. The Hg concentrations in the sediment core ranged from 14 to 351 ng g-1, with the high values occurred in the middle layers (1960-1996), which may be resulted from intensive human activities during this period, such as oil exploitation and booming of petrochemical industry, salt chemical industry and chlor-alkali plants. A significant positive correlation was found between THg and loss on ignition (LOI). The main fraction of Hg existed in residual part while the fraction that was easy to leach out from sediments accounted for only a small portion according to the results of BCR sequential extraction procedure. Multiple ecological risks indices and guidelines of Hg indicated that the sedimentary record presented an "intermediate state" for Hg contamination in the OYRE.


Assuntos
Sedimentos Geológicos/análise , Mercúrio/análise , Poluentes Químicos da Água/análise , Disponibilidade Biológica , Fracionamento Químico , China , Monitoramento Ambiental/métodos , Estuários , Mercúrio/farmacocinética , Rios , Poluentes Químicos da Água/farmacocinética
19.
Chemosphere ; 208: 731-739, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29894975

RESUMO

This study measured the concentrations of eight heavy metals, including copper (Cu), zinc (Zn), lead (Pb), chromium (Cr), cadmium (Cd), iron (Fe), manganese (Mn) and nickel (Ni), and the stable isotope ratios of δ13C and δ15N in 129 fish samples collected from the Yellow River Estuary (YRE) of China. Accumulation characteristics and possible sources of these heavy metals (HMs) were analyzed. The levels of HMs presented high variations among sampling sites, higher concentrations of ∑HMs were observed at the sites closest to the estuary. Cu and Cd in fishes of the YRE were much higher than those found in the fishes of other rivers of China. Furthermore, the mean concentrations of Cu, Zn, Pb, Cr and Cd were also significantly higher than those measured in the fishes of the same region twenty years ago. According to the results of correlation analysis and principal components analysis (PCA), Pb, Cr, Fe, Mn and Ni might be originated from similar sources. The values of δ13C and δ15N presented high variation in fishes, indicating a wide range of energy sources and trophic status of the investigated fish species. The mean concentrations of Pb, Cr and Cd in fishes were all lower than the recommended values enacted by the Chinese government. The human health risk assessment showed that the estimated daily intake (EDI) of these HMs did not exceed the permissible tolerable daily intake (PTDI) and oral reference dose (RfD), indicating a situation of no potential health risk for consumption of these fish species.


Assuntos
Exposição Dietética/análise , Estuários , Peixes , Isótopos/análise , Metais Pesados/análise , Medição de Risco , Animais , China , Cromo/análise , Cobre/análise , Humanos , Ferro/análise , Manganês/análise , Níquel/análise , Poluentes Químicos da Água/análise , Zinco/análise
20.
Sci Total Environ ; 613-614: 462-471, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28918278

RESUMO

The Yellow River Estuary is a significant fishery, but at present there are few studies about the concentrations of arsenic (As), mercury (Hg) and vanadium (V) in fish from this area, which might cause potential health risk to fish consumers. The aim of this study was to research on the accumulation and potential sources of heavy metals in the fish of the Yellow River Estuary. Arsenic, Hg, V and stable isotope ratios (δ15N and δ13C) in 11 species of 129 fish were analyzed. Results showed that the concentrations of As and Hg were all lower than the guideline levels established by international organizations and legal limits by several countries. The mean concentrations of V in samples in this study were significantly higher than the results of previous studies on other regions. Arsenic, Hg and V significantly differed across species (P<0.05), which might be due to the different foraging habitats and dietary habits of the studied fish. Values of δ15N and δ13C in fish from the study area ranged from 5.1‰ to 14.6‰ and from -27.6‰ to -14.5‰, indicating a wide range of trophic positions and energy sources. There was evidence of bioaccumulation of Hg, which could be explained by the positive correlation between Hg concentrations and δ15N in fish. Through estimation of daily intake of inorganic As (iAs), Hg and V via fish consumption, the heavy metal contamination level of fish samples fell in an acceptable range, indicating no potentially hazardous for human health.


Assuntos
Estuários , Peixes , Metais Pesados/análise , Poluentes Químicos da Água/análise , Animais , Arsênio/análise , Isótopos de Carbono/análise , China , Monitoramento Ambiental , Humanos , Mercúrio/análise , Isótopos de Nitrogênio/análise , Rios , Vanádio/análise
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