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1.
J Health Econ Outcomes Res ; 11(2): 49-57, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39267886

RESUMEN

Background: For patients with locally advanced or metastatic urothelial carcinoma (la/mUC), prognosis is poor and effective treatment options are limited. Erdafitinib is an oral fibroblast growth factor receptor (FGFR) kinase inhibitor approved by the FDA for the treatment of adults with la/mUC harboring FGFR alterations whose disease progressed following at least 1 prior line of therapy, including a PD-1 or PD-L(1) inhibitor, based on the phase 3, randomized THOR trial (NCT03390504, Cohort 1). Objective: To compare the efficacy and safety of erdafitinib vs enfortumab vedotin-ejfv (EV) in the absence of head-to-head comparison via an anchored matching-adjusted indirect comparison (MAIC). Methods: An anchored MAIC was conducted according to the National Institute for Health and Care Excellence Decision Support Unit guidance, with physician's choice of chemotherapy (docetaxel/paclitaxel and vinflunine) as the common comparator. Individual patient data from THOR were adjusted to match published key eligibility criteria and average baseline characteristics of EV-301, such as Bellmunt risk score, liver or visceral metastases, primary site, among others. Erdafitinib was then indirectly compared with EV using the relative treatment effects for the reweighted THOR population and those published for EV-301. Results: After matching, the effective sample size for THOR was 126 patients. The MAIC-recalculated hazard ratio (95% credible interval) for erdafitinib vs EV was 0.92 (0.54, 1.57) for overall survival and 0.93 (0.55, 1.56) for progression-free survival, yielding Bayesian probabilities of erdafitinib being better than EV of 62.1% and 60.5%, respectively. For response outcomes, the MAIC-recalculated risk ratio was 1.49 (0.56, 3.90) for confirmed objective response rate and 2.89 (0.27, 30.33) for confirmed complete response with probabilities of 72.6% and 81.3% for erdafitinib being better than EV, respectively. For safety, MAIC-yielded risk ratios of 1.09 (0.99, 1.21) for any treatment-related adverse events, 0.86 (0.57, 1.28) for grade 3+ TRAEs, and 1.02 (0.98, 1.06) for any treatment-emergent adverse events. Conclusion: The MAIC indicates comparable efficacy of erdafitinib vs EV for overall survival and progression-free survival, with erdafitinib showing a higher probability of achieving deep responses. While erdafitinib is associated with slightly more adverse events compared with EV, these events seem to be less severe.

2.
Sci Total Environ ; 951: 175394, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39128515

RESUMEN

In this study, coal and coal-based solid wastes (coal gangue, fly ash, bottom ash, desulfurized gypsum and tar residue) were collected from major coal mines, power plants and coking plants in Lianghuai mining area (LH), China, and were analyzed for 76 polycyclic aromatic compounds (PACs), 27 n-alkanes and 2 isoprenoids (phytane and pristane). The total n-alkanes concentrations and ∑76 PACs in raw coals (640 ± 600 and 180 ± 87 µg/g) were higher than those in coal-based solid wastes (47 ± 40 and 24 ± 25 µg/g), but were lower than those in tar residue (3700 and 63,000 µg/g). It was discovered that the depositional paleoenvironment in LH was mostly a lacustrine and freshwater environment with oxidizing conditions and mixed organic matter input, but the Huainan coalfield had stronger oxidizing conditions and more input of terrestrial organic matter than that of the Huaibei coalfield. Alkylated PACs made up 56 ± 12 % of the ∑76PACs in raw coals, whereas solid wastes mainly consisted of 16 EPA PAHs (66 ± 16 %). Coal combustion and gangue weathering altered the structural properties of n-alkanes and PACs, resulting in a significant loss of n-alkanes and PACs, a higher proportion of parent PACs, and an increased abundance of short n-alkanes in the products (No apparent change of n-alkanes composition was observed through gangue weathering). The toxicity of PACs in raw coal and its solid wastes in LH from high to low was tar residue, raw coal, coal gangue, and coal-fired products. This investigation further confirmed that traditional diagnostic ratios may distort source information, and that they should not be used to assess PACs sources from raw coal particles or coal gangues, but rather to identify combustion sources near the point source. In addition, Retene/(Retene + Chrysene) < 0.03 may indicate direct contamination of raw coal particles.

3.
Sci Total Environ ; 945: 173988, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38889819

RESUMEN

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.

4.
Environ Sci Pollut Res Int ; 31(14): 22012-22023, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38400976

RESUMEN

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.


Asunto(s)
Huesos/anomalías , Enanismo , Hexaclorociclohexano , Hidrocarburos Clorados , Deformidades Congénitas de las Extremidades , Lordosis , Plaguicidas , Humanos , Ríos , Epóxido de Heptaclor , Heptacloro , Mitotano , Agua , China
5.
Ecotoxicol Environ Saf ; 263: 115286, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37481858

RESUMEN

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.


Asunto(s)
Bifenilos Policlorados , Bifenilos Policlorados/análisis , Multimedia , Monitoreo del Ambiente/métodos , Agua , Suelo
6.
Environ Sci Pollut Res Int ; 30(23): 64254-64264, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37069373

RESUMEN

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.


Asunto(s)
Quinolonas , Contaminantes Químicos del Agua , Antibacterianos/análisis , Acuicultura , China , Monitoreo del Ambiente/métodos , Quinolonas/análisis , Medición de Riesgo , Ríos , Sulfanilamida , Sulfonamidas/análisis , Tetraciclinas/análisis , Contaminantes Químicos del Agua/análisis
7.
Sci Total Environ ; 879: 163045, 2023 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-36963675

RESUMEN

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.


Asunto(s)
Contaminantes Atmosféricos , Aceites Combustibles , Hidrocarburos Policíclicos Aromáticos , Compuestos Policíclicos , Compuestos Policíclicos/análisis , Carbón Mineral/análisis , Corteza de la Planta/química , Árboles , Contaminantes Atmosféricos/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , China , Monitoreo del Ambiente
8.
Ecotoxicol Environ Saf ; 250: 114479, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36603484

RESUMEN

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.


Asunto(s)
Mercurio , Metales Pesados , Selenio , Humanos , Anciano , Selenio/análisis , Cadmio/toxicidad , Cadmio/análisis , Mercurio/análisis , China , Cabello/química , Metales Pesados/toxicidad , Metales Pesados/análisis
10.
Adv Ther ; 39(5): 1976-1992, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35246820

RESUMEN

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.


Asunto(s)
Mieloma Múltiple , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Bortezomib/uso terapéutico , Dexametasona/uso terapéutico , Humanos , Lenalidomida/uso terapéutico , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/tratamiento farmacológico , Metaanálisis en Red , Resultado del Tratamiento
11.
Chemosphere ; 296: 134020, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35216981

RESUMEN

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.


Asunto(s)
Hidrocarburos Clorados , Plaguicidas , Contaminantes Químicos del Agua , China , DDT/análisis , Monitoreo del Ambiente , Sedimentos Geológicos/química , Hidrocarburos Clorados/análisis , Plaguicidas/análisis , Ríos/química , Suelo , Contaminantes Químicos del Agua/análisis
12.
Water Environ Res ; 93(11): 2795-2806, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34486191

RESUMEN

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.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente , Sedimentos Geológicos , Lagos , Metales Pesados/análisis , Medición de Riesgo , Contaminantes Químicos del Agua/análisis
13.
Ecotoxicol Environ Saf ; 214: 112095, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33667735

RESUMEN

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.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Químicos del Agua/análisis , China , Carbón Mineral/análisis , Monitoreo del Ambiente , Sedimentos Geológicos , Industrias , Medición de Riesgo , Ríos , Emisiones de Vehículos/análisis
14.
Bull Environ Contam Toxicol ; 105(2): 230-236, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32671410

RESUMEN

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.


Asunto(s)
Minas de Carbón , Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Hidrocarburos/análisis , Petróleo/análisis , Alcanos/análisis , China , Diterpenos/análisis , Cromatografía de Gases y Espectrometría de Masas , Hidrocarburos Policíclicos Aromáticos/análisis , Análisis de Componente Principal , Terpenos/análisis , Contaminantes Químicos del Agua/análisis
15.
Chemosphere ; 258: 127359, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32544807

RESUMEN

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.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Hidrocarburos Clorados/análisis , Plaguicidas/análisis , Bifenilos Policlorados/análisis , Movimientos del Aire , Regiones Antárticas , Océano Índico , Australia del Sur
16.
Environ Sci Pollut Res Int ; 26(34): 35094-35106, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31679141

RESUMEN

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.


Asunto(s)
Arsénico/análisis , Monitoreo del Ambiente , Mercurio/análisis , Contaminantes del Suelo/análisis , China , Humanos , Medición de Riesgo , Ríos , Suelo
17.
Arch Environ Contam Toxicol ; 77(4): 594-604, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31388704

RESUMEN

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.


Asunto(s)
Éteres Difenilos Halogenados/análisis , Contaminantes del Suelo/análisis , Carcinógenos Ambientales/análisis , Carcinógenos Ambientales/toxicidad , China , Conservación de los Recursos Naturales , Monitoreo del Ambiente , Retardadores de Llama/análisis , Éteres Difenilos Halogenados/toxicidad , Humanos , Medición de Riesgo , Contaminantes del Suelo/toxicidad
18.
Bull Environ Contam Toxicol ; 102(6): 843-847, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30993357

RESUMEN

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.


Asunto(s)
Bifenilos Policlorados/análisis , Ríos/química , Contaminantes del Suelo/análisis , Suelo/química , China , Monitoreo del Ambiente/métodos , Cromatografía de Gases y Espectrometría de Masas , Bifenilos Policlorados/química , Medición de Riesgo , Contaminantes del Suelo/química
19.
Mar Pollut Bull ; 140: 388-394, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30803658

RESUMEN

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.


Asunto(s)
Organismos Acuáticos/efectos de los fármacos , Bahías/química , Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , Animales , China , Metales Pesados/toxicidad , Medición de Riesgo , Mariscos/análisis , Contaminantes Químicos del Agua/toxicidad
20.
Mar Pollut Bull ; 135: 47-54, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30301061

RESUMEN

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.


Asunto(s)
Sedimentos Geológicos/análisis , Mercurio/análisis , Contaminantes Químicos del Agua/análisis , Disponibilidad Biológica , Fraccionamiento Químico , China , Monitoreo del Ambiente/métodos , Estuarios , Mercurio/farmacocinética , Ríos , Contaminantes Químicos del Agua/farmacocinética
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