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1.
Chemosphere ; 242: 125273, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31896195

RESUMO

Atmospheric processing may significantly increase solubility of iron in mineral dust, but the effects of heterogeneous reactions on iron solubility have been poorly understood. In this work, we investigated heterogeneous reaction of NO2 (15 ±â€¯1 and 2.5 ±â€¯0.1 ppmv, equal to ∼3.7 × 1014 and ∼6.2 × 1013 molecule cm-3) with hematite, magnetite and goethite at different relative humidities (RH, 0-90%), and changes in particulate nitrate and soluble iron due to heterogeneous reaction with NO2 were quantified as a function of time (up to 24 h). After reaction with 2.5 ±â€¯0.1 ppmv NO2 for 24 h (or less time), hematite and magnetite were fully saturated, while goethite was only partly deactivated. Nitrate yield was largest for goethite, and the mass ratio of formed nitrate to unreacted mineral only reached ∼1% or less after 24 h reaction. All the three minerals showed low reactivities towards NO2, and the average reactive uptake coefficients of NO2 in the first 3 h were found to be < 5 × 10-8. In addition, the increase in iron solubility was found to be small and in some cases even insignificant for the three minerals after heterogeneous reaction with NO2 for 24 h. Overall, the impacts of heterogeneous reaction of NO2 with hematite, magnetite and goethite on nitrate aerosol formation and iron solubility could be very limited.


Assuntos
Compostos Férricos/química , Óxido Ferroso-Férrico/química , Compostos de Ferro/química , Ferro/química , Minerais/química , Nitratos/análise , Óxidos de Nitrogênio/química , Aerossóis , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/química , Poeira/análise , Modelos Químicos , Solubilidade
2.
Sci Total Environ ; 700: 134502, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31693950

RESUMO

Organophosphate (OP) esters are emerging environmental contaminants, but little is known about their occurrence in dust. In this study, 19 OP triesters and their 11 diester degradation products were measured in indoor dust and outdoor dust collected from China. ∑OP triester concentrations in indoor dust (median: 2380 ng/g dry weight [dw]) were an order of magnitude higher than those in outdoor dust (446 ng/g dw). The median concentrations of ∑OP diesters in indoor and outdoor dust were 260 and 96.8 ng/g dw, respectively. Dust samples collected from eastern and southern China contained higher concentrations of ∑OP di- and tri-esters than those from the other regions. Dust from the most urbanized areas in China including Beijing, Shanghai, and Guangzhou exhibited the highest concentrations of ∑OP di- (>1000 ng/g dw) and triesters (>4000 ng/g dw). We also found notable concentrations of emerging aryl-OP triesters in dust (3.85-10.6 ng/g dw). Significant correlations existed between the concentrations of bis(2-ethylhexyl) phosphate (BEHP) and tris(2-ethylhexyl) phosphate (TEHP) (rho = 0.672-0.691, p < 0.01), as well as DPHP and triphenyl phosphate (TPHP) (rho = 0.537-0.766, p < 0.01) in dust samples, indicating that OP diesters originated from the degradation of triesters. High molar concentration ratios of DEP to triethyl phosphate (TEP) and DPHP to TPHP/ethylhexyl diphenyl phosphate (EHDPP) suggested that these OP triesters degrade readily. Significant correlations were found between the concentrations of ∑OP di- (R2 = 0.390, p < 0.05) and tri-esters (R2 = 0.475, p < 0.01) in paired indoor-outdoor dust samples, which suggested that indoor dust was the source of OP esters to the outdoor environment. The estimated daily intake (EDI) of ∑OP diesters through dust ingestion was 0.21 ng/kg bw/d for adults and 2.59 ng/kg bw/d for children. The exposure levels of OP diesters, DEP and DPHP, were comparable to those of their parent triester compounds.


Assuntos
Poeira/análise , Exposição Ambiental/estatística & dados numéricos , Ésteres/análise , Organofosfatos/análise , Poluição do Ar em Ambientes Fechados/análise , China , Monitoramento Ambiental , Retardadores de Chama , Humanos
3.
Sci Total Environ ; 701: 134755, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31704398

RESUMO

The objective of this study is to analyze the short-term effects of atmospheric pollutant concentrations (PM10, NO2 and O3) and heat and cold waves on the number of pre-term births and cases of low birth weight related to Saharan dust advection and biomass combustion. The dependent variables used in this analysis were the total number of births, births with low weight (>2.500 g) and pre-term births (<37 weeks), that occurred at the province level. Data provided by the NSI included: days with Saharan dust intrusion or biomass advection classified in terms of information provided by MITECO for each of the nine regions in Spain. A representative city was selected for reach region in which the registered average daily concentrations of PM10, NO2 and O3 (µg/m3) were used. These were also provided by MITECO. The daily maximum and daily minimum temperature (°C) used was those registered by the meteorological observatory station located in each province capital, provided by AEMET. Using Poisson log linear regression models, the associated relative risks (RR) were measured as well as the population attributable risk (PAR) corresponding to the variables that resulted statistically significant at p < 0.05 for days with and without intrusion of natural particulate matter. The results obtained show that the days with Saharan dust intrusion or advections due to biomass combustion- beyond the impact of PM10, primary pollutants such as NO2 (in Saharan intrusions), heat waves and O3 - are associated with the number of births, low birth weight and pre-term birth. The RR and percent PAR of the pollutants and the heat waves are greater than those obtained for PM10. The results of this study indicate that days with natural particulate matter due to biomass combustion or advection of Saharan dust put pregnant women at risk.


Assuntos
Poluição do Ar/estatística & dados numéricos , Poeira/análise , Exposição Materna/estatística & dados numéricos , Resultado da Gravidez/epidemiologia , África do Norte , Monitoramento Ambiental , Feminino , Humanos , Material Particulado/análise , Gravidez , Espanha
4.
Chemosphere ; 238: 124643, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31473532

RESUMO

Polychlorinated n-alkanes or chlorinated paraffins (CPs) contain a magnitude of structural isomers and are categorized as short-chain (SCCPs), medium-chain (MCCPs), and long-chain (LCCPs) CPs, according to the carbon chain lengths. In this study the Æ©SCCPs, Æ©MCCPs, and Æ©LCCP concentrations are reported for South African indoor dust and pet cat hair. The median concentrations of the Æ©CPs (C9-C37) ranged from 33 to 663 µg/g for freshly collected dust (FD), 36-488 µg/g for dust collected from household vacuum cleaner bags (VD), and 1.2-15 µg/g for cat hair (CH) samples. MCCPs were the dominant CP group, followed by SCCPs and LCCPs. The Æ©MCCP concentration ranged from 13 to 498 µg/g in dust and 0.6-6.5 µg/g in cat hair. SCCPs with shorter carbon chains and lower chlorine substitution were observed in cat hair. LCCPs with carbon chains > C20 were detected in dust and hair samples, possibly indicating the use of wax grade LCCP formulations. Non-traditional Kendrick mass defect plots were used to obtain information on the magnitude of CPs and provide evidence of possible interfering compounds. This is the first report on the occurrence of SCCPs, MCCPs, and LCCPs in the South African indoor environment.


Assuntos
Poeira/análise , Cabelo/química , Hidrocarbonetos Clorados/química , Parafina/química , Poluição do Ar em Ambientes Fechados , Animais , Gatos , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Parafina/análise , África do Sul
5.
Chemosphere ; 239: 124701, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31499316

RESUMO

Polybrominated diphenyl ethers, a class of flame retardants and endocrine disruptors, have been substituted in new products by organophosphate (OPFR) and replacement brominated flame retardants (RBFR). OPFRs and RBFRs readily migrate from consumer products into dust where humans are exposed via incidental ingestion and inhalation. We quantified concentrations and loadings of OPFRs and RBFRs in house dust samples (n = 317) collected from the homes of Cincinnati women between 2003 and 2006 and examined their associations with demographic and house characteristics. Tris-(1-chloro-2-propyl)-phosphate (TCIPP, geometric mean [GM]: 2140 ng g-1, range: 70.1-166,000 ng g-1), tris-(1,3-dichloro-2-propyl)-phosphate (TDCIPP, GM: 1840 ng g-1, range: 55.2-228,000 ng g-1), triphenyl phosphate (TPHP, GM: 1070 ng g-1, range: 34.1-62,100 ng g-1), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB, GM: 59.5 ng g-1, range: 2.82-7800 ng g-1), and bis-(2-ethylhexyl)-tetrabromophthalate (BEH-TEBP, GM: 121 ng g-1, range 2.17-13,600 ng g-1) were all detected in >90% of dust samples; tris-(2-chloroethyl)-phosphate (TCEP, GM: 669 ng g-1, range: 56.8-160,000 ng g-1) was detected in 80.1% of samples. Concentrations of EH-TBB and BEH-TEBP increased in house dust from 2003 to 2006. The number of people living in the home, race, education, floor type, and year of sample collection were associated with some OPFR and RBFR concentrations and loadings. This study suggests that OPFRs and RBFRs were ubiquitous in house dust during the PBDE phase-out and justifies more research on the consequences of exposure to these environmental chemicals.


Assuntos
Poeira/análise , Retardadores de Chama/análise , Éteres Difenil Halogenados/análise , Organofosfatos/análise , Adulto , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental , Poluentes Ambientais/análise , Feminino , Halogenação , Humanos , Ohio
6.
Ecotoxicol Environ Saf ; 187: 109838, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31677564

RESUMO

Due to population growth and the considerable increase in usage of the resources, Human environment quality has been highly threatened by pollutants in recent decades. Polycyclic aromatic hydrocarbons (PAHs) are widespread, persistent organic pollutants which are of great concern due to their carcinogenicity. The present study is the first investigation that assesses contamination, sources and cancer risk of 16 priority PAHs proposed by US EPA in urban dust samples (n = 80) taken in different land-uses of Tehran metropolis, the capital of Iran. Gas chromatography-mass spectrometry (GC-MS) is used to measure PAHs concentrations. The results showed that the average concentration of the total 16 PAHs and the average Benzo[a]pyrene total potency equivalency were 566 µg kg-1 dry weight and 36.4 µg kg-1, respectively. In the commercial and residential land-uses high molecular weight (HMW) PAHs were dominated, whereas in green lands, light molecular weight (LMW) PAHs showed maximum contribution. The highest concentration of total PAHs were observed in the commercial areas due to limited air circulation and heavy traffic loads. Incremental Lifetime Cancer Risk (ILCR) model was applied to evaluate the cancer risk of exposure to PAHs contaminated dust. Based on the results, Tehran's residents (children and adults) in various land-uses except for green lands, are in high potential cancer risk of PAHs via ingestion and dermal contact exposure routs. Ace, Chr, Pyr, and BghiP which are indicators of traffic emissions, were found to be predominant PAH contributors in urban dust of commercial areas. Also, Ace, Fl, Phe, and BghiP which are derived from fossil fuel combustion, were mainly observed in the industrial land-use. Based on the results of factor analysis and diagnostic ratios, Diesel/gasoline engine vehicular emissions and combustion were found to be the main sources of PAHs in urban dust of Tehran.


Assuntos
Poeira/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Neoplasias/epidemiologia , Hidrocarbonetos Policíclicos Aromáticos/análise , Adulto , Criança , Cidades , Gasolina/análise , Humanos , Indústrias , Irã (Geográfico) , Medição de Risco , Emissões de Veículos/análise
7.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 37(11): 823-826, 2019 Nov 20.
Artigo em Chinês | MEDLINE | ID: mdl-31826546

RESUMO

Objective: To understand the occupational hazard and distribution of silica dust (free SiO(2)≥10%) in the workplace environment of the enterprises in Fengxian District, and to provide scientific basis for improving the working environment and protecting the physical and mental health of the workers. Methods: Individual sampling monitoring and on-site labor hygiene investigation were conducted on 421 workers involved in 87 silicon dust enterprises in the jurisdiction from 2014 to 2018, and measured concentration-time weighted average (C(TWA)) . Results: The results showed that the range of the C(TWA) was (0.021~17.000) mg/m(3), the median was 1.600 mg/m(3), and the qualified rate of 30.88%. The difference of total dust concentration was statistically significant in different years (Z=38.831, P<0.05) . The qualified rate of small-scale enterprises is higher than that of medium-scale enterprises (χ(2)=9.472, P<0.05) . The qualified rate of other domestic enterprises is higher than that of private enterprises and foreign enterprises (χ(2)=10.089, P<0.05) . The acceptance rate of metal products manufacturing is lower than that of general equipment manufacturing and other manufacturing enterprises (χ(2)=64.626, P<0.05) . The qualification rate of natural ventilation is higher than that of mechanical ventilation (χ(2)=6.278, P<0.05) . Conclusion: The enterprises involved in silicon production in Fengxian District need to further strengthen the production process reform and improve the ventilation and dust removal protection measures. Widely carry out the publicity of occupational disease prevention and control law, conduct targeted pre-job training, improve workers' awareness of self-protection, and protect the occupational health of workers in many ways.


Assuntos
Poeira , Exposição Ocupacional , Dióxido de Silício , Local de Trabalho , Poeira/análise , Humanos , Exposição Ocupacional/análise , Saúde do Trabalhador , Dióxido de Silício/análise , Local de Trabalho/normas
8.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 37(11): 842-845, 2019 Nov 20.
Artigo em Chinês | MEDLINE | ID: mdl-31826551

RESUMO

Objective: Analyzes of the monitoring results of silicosis in key occupational disease monitoring in Tianjin in 2017, providing reference for continuous monitoring, and prevention and control work of silicosis. Methods: Monitor and analyze the current state of silica dust hazard enterprises, the health status of silica dust workers, and the characteristics of newly developed silicosis cases in accordance with the national 2017 work plan for key occupational disease monitoring and occupational health risk assessment. Results: In 2017, 210 enterprises have silica dust hazard in Tianjin, silica dust workplaces exceed the standard rate is 34.73%, 5 695 workers' health examination who contact with silica dust were collected. 2 were detected occupational contraindication, the abnormal detection rate of chest examination is 3.60%, the abnormal index of lung function mainly is FVC, the abnormal rate is 15.8%. The abnormal rate increases with working years. In 2017, 193 new cases of silicosis were reported most cases were developed after years of decontamination. Most enterprises with cases had already out of market, only 7 were still producing. Conclusion: The key prevention and control in Tianjin was enterprises with silica dust excess of standard, as well as older and longer working years workers, adopting effective measures to reduce the concentration of silica dust in workplace is a fundamental measure to reduce the risk of silicosis.


Assuntos
Doenças Profissionais , Exposição Ocupacional , Saúde do Trabalhador , Silicose , China/epidemiologia , Poeira/análise , Humanos , Doenças Profissionais/epidemiologia , Exposição Ocupacional/estatística & dados numéricos , Vigilância da População , Dióxido de Silício/análise , Silicose/epidemiologia
9.
Environ Health Prev Med ; 24(1): 72, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31805868

RESUMO

BACKGROUND: Lead is a toxic metal abundant in the environment. Consumption of food contaminated at low levels of lead, especially by small children and pregnant women, raises a health concern. METHODS: Duplicated food portions and drinking water were collected over 3 days from 88 children and 87 pregnant women in Shimotsuke, Tochigi, Japan. Participants were recruited in this study between January 2014 and October 2015. Dust was also collected from their homes. Lead concentrations were measured and consequent oral lead exposure levels were estimated for this population at high risk to environmental toxicants. Lead concentrations of peripheral and cord blood, taken from children and pregnant women, and were also analyzed. RESULTS: Lead concentrations in food, drinking water, and house dust were low in general. Oral lead exposure to lead was higher for children (Mean ± SEM; 5.21 ± 0.30 µg/kg BW/week) than in pregnant women (1.47 ± 0.13 µg/kg BW/week). Food and house dust were main sources of lead contamination, but the contribution of house dust widely varied. Means ± SEM of peripheral and cord blood lead concentrations were 0.69 ± 0.04 µg/dL and 0.54 ± 0.05 µg/dL, respectively for pregnant women and 1.30 ± 0.07 µg/dL (peripheral only) in children. We detect no correlation between smoking situations and blood lead concentration in pregnant women. CONCLUSION: We conclude that oral lead exposure levels for Japanese children and pregnant women were generally low, with higher concentrations and exposure for children than for pregnant women. More efforts are necessary to clarify the sources of lead contamination and reduce lead exposure of the population at high risk even in Japan.


Assuntos
Exposição Dietética/análise , Poeira/análise , Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Chumbo/análise , Adulto , Pré-Escolar , Água Potável/análise , Poluentes Ambientais/sangue , Feminino , Sangue Fetal/química , Humanos , Lactente , Japão , Chumbo/sangue , Masculino , Gravidez , Adulto Jovem
10.
J Environ Sci (China) ; 86: 107-119, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31787175

RESUMO

Phthalate esters (PAEs), typical pollutants widely used as plasticizers, are ubiquitous in various indoor and outdoor environments. PAEs exist in both gas and particle phases, posing risks to human health. In the present study, we chose four typical kinds of indoor and outdoor environments with the longest average human residence times to assess the human exposure in Hangzhou, including newly decorated residences, ordinary residences, offices and outdoor air. In order to analyze the pollution levels and characteristics of 15 gas- and particle-phase PAEs in indoor and outdoor environments, air and particulate samples were collected simultaneously. The total PAEs concentrations in the four types of environments were 25,396, 25,466.8, 15,388.8 and 3616.2 ng/m3, respectively. DEHP and DEP were the most abundant, and DMPP was at the lowest level. Distinct variations in the distributions of indoor/outdoor, gas/particle-phase and different molecular weights of PAEs were observed, showing that indoor environments were the main sources of PAEs pollution. While most PAEs tended to exsit in indoor sites and gas-phase, the high-molecular-weight chemicals tended to exist in the particle-phase and were mainly found in PM2.5. PAEs were more likely adsorbed by small particles, especially for the indoor environments. There existed a good correlation between the particle matter concentrations and the PAEs levels. In addition, neither temperature nor humidity had obvious effects on the distributions of the PAEs concentrations.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Ácidos Ftálicos/análise , Poluição do Ar em Ambientes Fechados/análise , China , Poeira/análise , Material Particulado/análise
11.
Ann Agric Environ Med ; 26(4): 644-655, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31885240

RESUMO

CASE DESCRIPTION: Five workers (2 males and 3 females) employed in a furniture factory located in eastern Poland developed hypersensitivity pneumonitis (HP) after the pine wood used for furniture production was replaced by birch wood. All of them reported onset of respiratory and general symptoms (cough, shortness of breath, general malaise) after inhalation exposure to birch dust, showed crackles at auscultation, ground-glass attenuations in HRCT examination, and lymphocytosis in the BAL examination. The diagnosis of acute HP was set in 4 persons and the diagnosis of subacute HP in one. IDENTIFICATION OF SPECIFIC ALLERGEN: Samples of birch wood associated with evoking disease symptoms were subjected to microbiological analysis with the conventional and molecular methods. Two bacterial isolates were found to occur in large quantities (of the order 108 CFU/g) in examined samples: Gram-negative bacterium of the species Pantoea agglomerans and a non-filamentous Gram-positive actinobacterium of the species Microbacterium barkeri. In the test for inhibition of leukocyte migration, 4 out of 5 examined patients showed a positive reaction in the presence of P. agglomerans and 2 in the presence of M. barkeri. Only one person showed the presence of precipitins to P. agglomerans and none to M. barkeri. In the inhalation challenge, which is the most relevant allergological test in the HP diagnostics, all patients reacted positively to P. agglomerans and only one to M. barkeri. The results indicate that P. agglomerans developing in birch wood was the main agent causing HP in the workers exposed to the inhalation of dust from this wood, while the etiologic role of M. barkeri is probably secondary. CONCLUSION: The results demonstrate that apart from fungi and filamentous actinobacteria, regarded until recently as causative agents of HP in woodworkers, Gram-negative bacteria and non-filamentous actinobacteria may also elicit disease symptoms in the workers processing wood infected with large amounts of these microorganisms. The results obtained also seem to indicate that cellular-mediated reactions are more significant for causing disease symptoms compared to those that are precipitin-mediated.


Assuntos
Actinobacteria/isolamento & purificação , Poluentes Ocupacionais do Ar/efeitos adversos , Alveolite Alérgica Extrínseca/microbiologia , Betula/microbiologia , Poeira/análise , Exposição por Inalação/efeitos adversos , Pantoea/isolamento & purificação , Actinobacteria/genética , Actinobacteria/fisiologia , Doença Aguda , Adulto , Poluentes Ocupacionais do Ar/análise , Alveolite Alérgica Extrínseca/etiologia , Feminino , Humanos , Exposição por Inalação/análise , Masculino , Pessoa de Meia-Idade , Pantoea/genética , Pantoea/fisiologia , Polônia , Madeira/microbiologia
12.
Environ Sci Pollut Res Int ; 26(34): 35082-35093, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31676940

RESUMO

The replacement of fossil-based fuels by renewable fuels (biofuels) was proposed in the IPCC report, as an alternative to reduce greenhouse gas emission and reach out to a low-carbon economy. On this perspective, the Brazilian government had implemented a renewable energy program based on the use of ethanol in the transport sector. This work evaluates the scenario of pollutant gas emissions and particulate material that comes from the biomass burning process involved in ethanol production cycle, in the city of Campos dos Goytacazes, Brazil. The gases and particulate material emitted by sugarcane and bagasse burning processes-the last one in energy co-generation mills-were analyzed. A laboratory-controlled burning of both samples was realized in an oven with temperature ramp from 250 to 400 °C, at a regular rate of 50 °C. The gas samples were collected directly from the oven's exhaust pipe. The particulates obtained were the residual material taken out of the burned samples: a powder with the aspect of soot. A photoacoustic spectroscopy system coupled with quantum cascade laser and electrochemical analyzers was used to measure the emission of polluting gases such as N2O, CO2, CO, NOx (NO, NO2), and SO2 in ppmv range. Fluorescent X-ray spectrometry was applied to evaluate the chemical composition of particulate material, enabling the identification of elements such as Si, Al, Ca, K, Fe, S, P, Ti, Mn, Cu, Zn, Sc, V, Cu, and Sr.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Etanol/análise , Biocombustíveis/análise , Biomassa , Brasil , Carbono/análise , Poeira/análise , Meio Ambiente , Combustíveis Fósseis/análise , Gases/análise , Fuligem/análise , Emissões de Veículos/análise
13.
Environ Pollut ; 255(Pt 3): 113350, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31671370

RESUMO

A study was undertaken to test the hypothesis that the presence of fly ash and other artifactual materials (AMs) significantly increases the toxicity of urban soil and street dust. AMs were distinguished as artifacts (artificial particles > 2 mm in size), and particulate artifacts (≤2 mm in size); street dust was the <63 µm fraction of street sediments. Reference artifacts, street dusts, and topsoils representing different land use types in Detroit, Michigan were analyzed for miscellaneous radionuclides, trace elements, magnetic susceptibility (MS), and acetic acid-extractable (leachable) Pb. Background levels were established using native glacial sediments. Street sediments were found to have a roadside provenance, hence street dusts inherited their contamination primarily from local soils. All soils and dusts had radionuclide concentrations similar to background levels, and radiological hazard indices within the safe range. Artifacts, fly ash-impacted soils and street dusts contained elevated concentrations of toxic trace elements, which varied with land use type, but none produced a significant amount of leachable Pb. It is inferred that toxic elements in AMs are not bioavailable because they are occluded within highly insoluble materials. Hence, these results do not support our hypothesis. Rather, AMs contribute to artificially-elevated total concentrations leading to an overestimation of toxicity. MS increased with increasing total concentration, hence proximal sensing can be used to map contamination level, but the weak correlation between total and leachable Pb suggests that such maps do not necessarily indicate the associated biohazard. Home site soils with total Pb concentrations >500 mg kg-1 were sporadically toxic. Thus, these results argue against street dust as the local cause of seasonally elevated blood-Pb levels in children. Lead-bearing home site soil tracked directly indoors to form house dust is an alternative exposure pathway.


Assuntos
Monitoramento Ambiental , Poluentes do Solo/toxicidade , Criança , Cidades , Poeira/análise , Humanos , Metais Pesados/análise , Michigan , Medição de Risco/métodos , Solo , Poluentes do Solo/análise , Urbanização
14.
Environ Monit Assess ; 191(12): 740, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31712911

RESUMO

The aim of this study was to assess the effects of stone crushing dust pollution on three commonly cultivated fruit plant species (Vitis vinifera L., Morus alba L., and Prunus armeniaca L.) and on the health of workers working at crushing plants. The trial was carried out on fruit plant species grown close to the stone crushing units located near the northwestern (Brewery) bypass of Quetta city, Pakistan, near National Highway NH-25. Plant materials were collected from three polluted sites at a distance of 500, 1000, and 1500 m, respectively, away from the stone crushing units and one locality of comparatively clean air considered a control at 4000 m away from these crushing components. To know the status of air disorder near the experimental sites, the suspended particulate matters and both oxides of sulfur and nitrogen were also noted during operating hours. Consequences of the study indicated that during the crushing process, a fine aerosol of stone dust is often generated which could cause a significant health hazard to workers and also affect plant productivity due to the smothering of plant stomata. Environmental data designated that the average highest evaluated total suspended particulate matter (TSPM), NOx, and SOx were 7400 µg/m3, 803.7 µg/m3, and 216 µg/m3, respectively, at 500-m distance which gradually decreases as the distance increases-all of these pose a health risk to operators. The maximum deposit dust washed from the plant leaf surface under study was found to be 8.2, 4.6, and 4.4 at the distance of 500 m in all the investigated plant species which was highly significantly higher than that of the control site (4000 m). Among the plant species, the maximum dust fall was noted on the leaves of Vitis vinifera L., and minimum was on the leaves of Prunus armeniaca. The locations affected by more stone dust pollution (500 m) were leading to a reduction in the yield and quality of fruits. The studied stone crushing units had high percentages of closed stomata both on the upper sides (Us) and lower sides (Ls) of leaves at 500-m distance from stone crushing installations. Data regarding workers' health indicated the maximum age distribution among the workers was between the age groups of 20-35 years (46.15%). Results also showed that stone crushing workers suffered from symptoms of respiratory diseases (82.17%), allergies (72.13%), headaches (75.09%), coughing (78.36%), and tiredness (92.31%).


Assuntos
Poluentes Ocupacionais do Ar/análise , Poeira/análise , Exposição Ambiental/análise , Plantas , Adulto , Aerossóis , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental/métodos , Poluição Ambiental , Humanos , Exposição Ocupacional , Paquistão , Material Particulado/análise , Desenvolvimento Vegetal , Adulto Jovem
15.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 37(10): 781-784, 2019 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-31726512

RESUMO

Objective: To discuss the difference between pyrophosphoric acid method and infrared spectrophotometry for the determination of silica content in dust. Methods: The content of silica in the laboratory comparison samples organized by CDC Occupational Health Institute in China in 2018, and purchased quality control samples were determined by pyrophosphate method. Meanwhile, the samples were qualitatively and quantitatively analyzed by infrared spectrophotometry, and the results obtained by the two methods were compared. Results: Four samples (062C1、062C2、GDOHZKTG012-1、GDOHZKTG012-2) were detected by pyrophosphate method and infrared spectrophotometry. The results of pyrophosphate method were 55.49%, 5.24%, 4.90% and 54.72%, respectively. The results of infrared spectrophotometry were 0.91%, 1.87%, 1.29% and 1.16% respectively. Conclusion: The content of silica in dust determined by pyrophosphate method is higher than that by infrared spectrophotometry.


Assuntos
Poluentes Ocupacionais do Ar/análise , Difosfatos , Poeira/análise , Dióxido de Silício/análise , Espectrofotometria Infravermelho , China
16.
Environ Health Perspect ; 127(11): 117003, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31724879

RESUMO

BACKGROUND: Atherosclerotic cardiovascular disease has become the leading cause of death worldwide, and environmental pollutants are increasingly recognized as risk factors for atherosclerosis. Liver X receptors (LXRs) play a central role in atherosclerosis; however, LXR activity of organic pollutants and associated potential risk of atherosclerosis have not yet been characterized. OBJECTIVES: This study aimed to explore whether LXR-antagonistic chemicals are present in indoor house dust and, if so, to characterize this activity in relation to changes in macrophages in vitro and cardiovascular disease indicators in vivo in an atherosclerosis ApoE-/- mouse model. METHODS: We used a His-LXRα-pull-down assay and a nontarget high-resolution mass spectrometry method to screen house dust collected from Chinese homes for LXRα- and LXRß-antagonist activity. A chemical identified in this manner was assessed for its ability to induce cholesterol efflux and foam cell formation in RAW264.7 macrophages, to down-regulate the expression of two LXR-dependent genes, ABCA1 and ABCG1, and finally to induce atherosclerotic lesions in vivo using an ApoE-/- mouse model. RESULTS: We identified the flame retardants triphenyl phosphate (TPHP) and 2-ethylhexyl diphenyl phosphate (EHDPP) in house dust samples and demonstrated their ability to antagonize LXRs. The potency of TPHP was similar to that of the LXR-antagonist SR9238. TPHP could also inhibit cholesterol efflux and promote foam cell formation in RAW264.7 macrophages and mouse peritoneal macrophages and significantly promoted atherosclerotic lesion formation in the ApoE-/- mouse model. CONCLUSIONS: We found LXR-antagonist chemicals in environmental samples of indoor dust from Chinese homes. One of the chemicals, TPHP, was able to promote the development of atherosclerotic lesions in the ApoE-/- mouse model. These results highlight the need to assess the LXR-antagonist activities of pollutants in future environmental management programs. https://doi.org/10.1289/EHP5039.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Poluição do Ar em Ambientes Fechados/análise , Aterosclerose/fisiopatologia , Poeira/análise , Animais , Aterosclerose/induzido quimicamente , China , Receptores X do Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Células RAW 264.7
17.
Environ Monit Assess ; 191(11): 668, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31650348

RESUMO

Microplastics (of size < 5 mm) pollution in our environment is of current concern by researchers, public media and non-governmental organizations. Implications by their presence in aquatic and soil ecosystems have been well studied and documented, but less attention has been paid on airborne microplastics (MPs). Studies concerning airborne microplastics started from 2016 and only a few (n = 13) have been published to date. Although, studies may increase in the following years, since air is very important for human survival. Microplastics have been observed in atmospheric fallouts in indoor and outdoor environments using a sampling or vacuum pump, rain sampler, and/or particulate fallout collector. Identification and quantification have been carried out by visual, spectroscopic, and spectrometric techniques. Factors such as meteorological, climatic, and anthropogenic influence the distribution and movement of airborne MP. Human exposure may be through inhalation, dermal, and open meal during fallout, with their potential biopersistence and translocation. Ingestion may cause localized inflammation and cancer due to responses by the immune cells, especially in individuals with compromised metabolism and poor clearance mechanisms. Ecological risks involve possible contamination of the ecosystem through a dynamic relationship of MPs in soil, water, and air forming a MP contamination cycle. The present review aimed at providing a comprehensive overview of current knowledge or information regarding microplastics in air, identifying gap in knowledge, and giving suggestions for future research.


Assuntos
Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Material Particulado/análise , Poeira/análise , Ecossistema , Humanos , Solo
18.
Wei Sheng Yan Jiu ; 48(4): 583-593, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31601339

RESUMO

OBJECTIVE: To understand the differences in the types and levels of antibiotic resistance genes contamination in the dust of air conditioning filters in hospital inpatient wards. METHODS: Wet cotton swabs were used to collect dust samples from air conditioning filters in 19 wards of 7 departments of a third-grade general hospital in Wuhan. The 24 antibiotic resistance genes related to 6 major antibiotics were qualitatively detected by PCR, and 6 typical resistance genes were detected by real-time PCR. RESULTS: Sulfonamides(sulI, sulII), ß-lactams(mecA, blaOXA-51, blaTEM, blaCTX-M, blaSHV, blaKPC, blaNDM-1, blaIMP, blaVIM), aminoglycosides(aac(6᾿-aph(2᾿, aacC2), macrolides(ermA, ermC, ereA), quinolones(qnrA, qnrB, qnrS), a total of five categories of 19 antibiotic resistance genes were detected in the dust of the filter. These include four carbapenem resistance genes(blaNDM-1, blaIMP, blaVIM, blaKPC). The average of absolute content(copies/g) of the six typical resistance genes from high to low was: sulI(1. 06×10~9)>sulII(1. 78×10~8)>blaNDM-1(3. 97×10~7)>aac(6᾿-aph(2᾿(3. 20×10~7)>blaTEM(1. 03×10~7)>aacC2(1. 13×10~6). Among the seven tested departments, traumatic surgery detected up to 18 resistant gene species and 6 typical genes with the highest absolute content. The absolute content of six typical genes in ICU and surgical wards was higher than medical wards. CONCLUSION: A variety of antibiotic resistance genes are detected in the dust of some hospital ward air conditioning filters, suggesting that there may be current or past pollution of resistant bacteria in the relevant environment.


Assuntos
Ar Condicionado , Microbiologia do Ar , Resistência Microbiana a Medicamentos/genética , Poeira/análise , Antibacterianos , Carbapenêmicos , China , Testes de Sensibilidade Microbiana , beta-Lactamases
19.
Environ Pollut ; 255(Pt 2): 113332, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31606663

RESUMO

Organophosphate esters (OPEs) in indoor dust were closely related to human health. However, OPE contamination in college library dust remained unknown at present. In this study, OPEs were first investigated in 78 indoor dust samples and 26 field blanks of 26 college libraries from 13 prefecture-level cities across China between October and December 2017. The total OPEs fell in the range of 8706-34872 ng/g, and were dominated by tris(2-chloroisopropyl) phosphate (TCIPP), tris(2-chloroethyl) phosphate (TCEP) and tris(2-butoxyethyl) phosphate (TBOEP). OPEs exhibited geography-specific distributions, with high levels in Beijing, Shanghai and Guangzhou. OPEs significantly correlated with population density and gross domestic product (p < 0.01), indicating the distinct effect of these two indicators on OPE pollution. Analysis of pollution source indicated volatilization and abrasion as main emission pathways of OPEs from OPEs-added products to dust. The daily exposure doses (DEDs) of OPEs via dust ingestion, inhalation and dermal contact were similar for male and female students, ranging from 1.35 to 5.92 ng/kg-bw/day during study time in libraries (25% of day). High DEDs were found in Beijing, shanghai and Guangzhou, indicating high exposure risk of OPEs to college students in large cities. The non-carcinogenic and carcinogenic risks of OPEs to college students were quantitatively evaluated based on the oral reference dose and cancer slope factor of OPEs recently updated by USEPA, and all much lower than the threshold risk values. However, the potential risk may occur if exposure to OPEs is high in other microenvironments over remaining hours of the day.


Assuntos
Poeira/análise , Exposição Ambiental/análise , Organofosfatos/análise , Universidades , Pequim , China , Cidades , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental , Ésteres/análise , Feminino , Retardadores de Chama/análise , Humanos , Estados Unidos , United States Environmental Protection Agency
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