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1.
Ecotoxicol Environ Saf ; 211: 111959, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33486383

RESUMEN

Indoor biomass burning produces large amounts of small particles and hazardous contaminants leading to severe air pollution and potentially high health risks associated with inhalation exposure. Personal samplers provide more accurate estimates of inhalation exposure. In this study, inhalation exposure to size-segregated particles and particulate polycyclic aromatic hydrocarbons (PAHs) for the biomass user was studied by deploying personal samplers. The study found that daily PM2.5 inhalation exposure level was as high as 121 ± 96 µg/m3, and over 84% was finer PM1.0. For PAHs, the exposure level was 113 ± 188 ng/m3, with over 77% in PM1.0. High molecular weight PAHs with larger toxic potentials enriched in smaller particles resulting in much high risks associated with PAHs inhalation exposure. Indoor exposure contributed to ~80% of the total inhalation exposure as a result of high indoor air pollution and longer residence spent indoor. The highest exposure risk was found for the male smoker who conducted cooking activities at home.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Monitoreo del Ambiente , Exposición por Inhalación/estadística & datos numéricos , Material Particulado/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminación del Aire/análisis , Contaminación del Aire Interior/análisis , Biomasa , Carbón Mineral/análisis , Culinaria , Polvo , Vivienda , Humanos , Exposición por Inhalación/análisis , Tamaño de la Partícula , Población Rural , Tibet
2.
Chemosphere ; 267: 129181, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33340883

RESUMEN

The bioaccessibility of metal(loid)s in ambient particulate matter (PM) has been recently used to represent the risk of inhalation exposure. Nevertheless, different methodological factors affect the bioaccessibility values; among these, the type and composition of surrogate biological fluids and the liquid to solid ratio have been revealed to be the most important. To better understand how these methodological aspects affect the bioaccessibility, a reference material corresponding to urban dust (SRM1648a) was contacted with synthetic biological fluids commonly used in the literature representing surrogate fluids that may interact with fine (Gamble's solutions, artificial lysosomal fluid (ALF)) and coarse particles (gastric fluid), for liquid to solid (L/S) ratios ranging from 500 to 20,000. Visual MINTEQ 3.1. was used to enhance the discussion on how the solubility of metals in the leaching solution depends on the composition of the simulated fluids and the speciation of metals. The results obtained indicate that a small change in the composition of Gamble's solution (the presence of glycine) may increase significantly the bioaccessibility at a L/S ratio of 5,000. The highest bioaccessibility of most of the studied metal(loid)s at a L/S ratio of 5,000 was found for ALF fluid. The study of the effect of the L/S ratio showed that metal(loid)s bioaccessibility in Gamble's fluid increased logarithmically with increasing L/S ratio, while it remained practically constant in ALF and gastric fluid. This different behavior is explained assuming that the leaching of metal(loid)s in Gamble's solution is solubility-controlled, while in ALF and gastric fluid is availability-controlled.


Asunto(s)
Polvo , Oligoelementos , Exposición por Inhalación/análisis , Metales , Material Particulado
3.
J Occup Environ Hyg ; 18(2): 72-83, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33315526

RESUMEN

Simple plastic face shields have numerous practical advantages over regular surgical masks. In light of the spreading COVID-19 pandemic, the potential of face shields as a substitution for surgical masks was investigated. In order to determine the efficacy of the protective equipment we used a cough simulator. The protective equipment considered was placed on a manikin head that simulated human breathing. Concentration and size distribution of small particles that reached the manikin respiration pathways during the few tens of seconds following the cough event were monitored. Additionally, water sensitive papers were taped on the tested protective equipment and the manikin face. In the case of frontal exposure, for droplet diameter larger than 3 µm, the shield efficiency in blocking cough droplets was found to be comparable to that of regular surgical masks, with enhanced protection for portions of the face that the mask does not cover. Additionally, for finer particles, down to 0.3 µm diameter, a shield blocked about 10 times more fine particles than the surgical mask. When exposure from the side was considered, the performance of the shield was found to depend dramatically on its geometry. While a narrow shield allowed more droplets and aerosol to penetrate in comparison to a mask under the same configuration, a slightly wider shield significantly improved the performance. The source control potential of shields was also investigated. A shield, and alternatively, a surgical mask, were placed on the cough simulator, while the breathing simulator, situated 60 cm away in the jet direction, remained totally exposed. In both cases, no droplets or particles were found in the vicinity of the breathing simulator. Conducted experiments were limited to short time periods after expiratory events, and do not include longer time ranges associated with exposure to suspended aerosol. Thus, additional evidence regarding the risk posed by floating aerosol is needed to establish practical conclusions regarding actual transmittance reduction potential of face shields and surgical face masks.


Asunto(s)
/prevención & control , Exposición por Inhalación/análisis , Máscaras/normas , Equipo de Protección Personal/normas , /aislamiento & purificación , Aerosoles/análisis , Microbiología del Aire , Tos/virología , Monitoreo del Ambiente , Humanos , Transmisión de Enfermedad Infecciosa de Paciente a Profesional/prevención & control , Exposición por Inhalación/prevención & control , Ensayo de Materiales , Exposición Profesional/análisis , Exposición Profesional/prevención & control
4.
Ecotoxicol Environ Saf ; 205: 111365, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-32977286

RESUMEN

Work in wastewater treatment plants (WWTPs) can be associated with respiratory symptoms and diarrhea. The aim of this study was to obtain knowledge about WWTP workers' exposure to airborne bacteria and endotoxin, and the inflammatory potential (TIP) of their exposure, and to evaluate the risk posed by the exposure by 1) calculating a hazard index and relating the exposure to suggested occupational exposure limits (OELs), 2) estimating the potential deposition of bacteria in the airways, 3) relating it to the risk group classification of bacteria by the European Union, and 4) estimating the TIP of the personal exposure. A cohort of 14 workers were followed over one year. Bioaerosols were collected using personal and stationary samplers in a grid chamber house and an aeration tank area. Airborne bacteria were identified using (MALDI-TOF MS), and TIP of exposure was measured using HL-60 cells. A significant effect of season, work task, and person was found on the personal exposure. A hazard index based on exposure levels indicates that the risk caused by inhalation is low. In relation to suggested OELs, 14% and 34% of the personal exposure were exceeded for endotoxin (≥50 EU/m3) and bacteria (≥500 CFU/m3). At least 70% of the airborne bacteria in the grid chamber house and the aeration tank area could potentially deposit in the lower respiratory tract. From the personal samples, three of 131 bacterial species, Enterobacter cloacae, Staphylococcus aureus, and Yersinia enterocolitica are classified within Risk Group 2. Seven additional bacteria from the stationary samples belong to Risk Group 2. The bacterial species composition was affected significantly by season (p = 0.014) and by sampling type/area (p = 0.001). The TIP of WWTP workers' exposure was higher than of a reference sample, and the highest TIP was measured in autumn. TIP of personal exposure correlated with bacterial exposure. Based on the geometric average exposures to endotoxin (9.2 EU/m3) and bacteria (299 CFU/m3) and based on the calculated hazard index, the risk associated with exposure is low. However, since 43 of 106 exposure levels exceed suggested OELs, the TIP of exposure was elevated and associated with bacterial exposure, and WWTP workers were exposed to pathogenic bacteria, a continued focus on preventive measures is important. The identification of bacteria to species level in personal samples was necessary in the risk assessment, and measurement of the microbial composition made the source tracking possible.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Exposición Profesional/análisis , Instalaciones de Eliminación de Residuos , Eliminación de Residuos Líquidos , Microbiología del Aire , Bacterias , Endotoxinas/análisis , Monitoreo del Ambiente/métodos , Humanos , Exposición por Inhalación/análisis , Exposición Profesional/estadística & datos numéricos , Estaciones del Año , Aguas Residuales/microbiología
5.
PLoS One ; 15(9): e0239010, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32925951

RESUMEN

Enclosed underground excavation worksite has an environment with poor ventilation and exposure to hazardous substances from diesel engine exhaust and construction materials. The objective of this study was to evaluate the exposure level of elemental carbon (EC), organic carbon (OC), total carbon (TC), polycyclic aromatic hydrocarbons (PAHs), dust and crystalline silica (CS) during underground excavation work for top down construction buildings. Active local air sampling for EC, OC, and TC (n = 105), PAHs (n = 50), dust (n = 34) and CS (n = 34) was conducted from inside and outside the excavator at underground excavation workshop in four different construction sites. EC, OC, TC and CS were sampled with each respirable and total particulates. EC, OC, and TC were collected on quartz-filter and analyzed using the thermal optical transmittance method. PAHs was collected on polytetrafluorethylene filter with XAD-2 and analyzed using liquid chromatography with fluorescence detector. CS and particulates were collected on poly vinyl chloride filter and analyzed using fourier-transform infrared spectroscopy. The geometric mean of respirable EC, OC, TC, total PAHs, respirable dust and respirable CS were 8.69 µg/m3, 34.32 µg/m3, 44.96 µg/m3, 6.818 µg/m3 0.13 mg/m3 and 0.02 mg/m3 from inside the excavator and 33.20 µg/m3, 46.53 µg/m3, 78.21 µg/m3, 3.934 µg/m3, 0.9 mg/m3 and 0.08 mg/m3 from outside the excavator (underground excavation workshop), respectively. The EC and RCS concentration from outside the excavator is significantly higher than that of inside the excavator (p<0.01). The worksite with rock ground, higher vehicle density, blasting and enclosed environments had higher exposure to EC than other sites (p<0.05). There was no significant difference of EC concentration between total and respirable particulates. In top down construction sites, EC concentrations during underground excavation work exceeded recommended exposure limits as 20 µg/m3, accounted for about 50% of the total sample, and the level of concentration of RCS exceeded 1.5 times of occupational exposure limit, 0.05 mg/m3. Efforts are needed to minimize exposure to diesel engine exhaust and silica in underground excavation sites. Management of diesel engine vehicle, supply of fresh air and ventilation and introducing water facilities to create wet environment in underground worksites are strongly suggested.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Exposición a Riesgos Ambientales/efectos adversos , Monitoreo del Ambiente/métodos , Carbono/análisis , Polvo/análisis , Exposición a Riesgos Ambientales/análisis , Humanos , Exposición por Inhalación/análisis , Exposición Profesional/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , República de Corea , Dióxido de Silicio/análisis , Emisiones de Vehículos/análisis , Lugar de Trabajo
6.
Artículo en Inglés | MEDLINE | ID: mdl-32858967

RESUMEN

As part of the assessment and management of chemical risk and occupational hygiene, retrospective exposure assessment (REA) to chemical agents can be defined as the estimate of exposure associated with a person's work history. The fundamental problem underlying the reconstruction of the exposure is that of transforming this type of information in quantitative terms to obtain an accurate estimate. REA can follow various approaches, some of which are technically complicated and both time and resource consuming. The aim of this systematic review is to present the techniques mainly used for occupational REA. In order to carry out this evaluation, a systematic review of the scientific literature was conducted. Forty-four studies were identified (published from 2010 to date) and analyzed. In exposure reconstruction studies, quantitative approaches should be preferable, especially when estimates will be used in the context of health impact assessment or epidemiology, although it is important to stress how, ideally, the experimental data available for the considered scenario should be used whenever possible as the main starting information base for further processing. To date, there is no single approach capable of providing an accurate estimate of exposure for each reasonably foreseeable condition and situation and the best approach generally depends on the level of information available for the specific case. The use of a combination of different reconstruction techniques can, therefore, represent a powerful tool for weighting and integrating data obtained through qualitative and quantitative approaches, in order to obtain the best possible estimate.


Asunto(s)
Exposición por Inhalación/análisis , Exposición Profesional/efectos adversos , Salud Laboral , Medición de Riesgo/métodos , Asbestos/efectos adversos , Monitoreo del Ambiente , Humanos
7.
Environ Pollut ; 265(Pt B): 115070, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32806460

RESUMEN

Particle-bound pollutants can pose a health risk to humans. Inhalation exposure evaluated by total contaminant concentrations significantly overestimates the potential risk. To assess the risk more accurately, bioavailability, which is the fraction that enters into the systemic circulation, should be considered. Researchers have replaced bioavailability by bioaccessibility due to the rapid and cost-efficient measurement for the latter, especially for assessment by oral ingestion. However, contaminants in particulates have different behavior when inhaled than when orally ingested. Some of the contaminants are exhaled along with exhalation, and others are deposited in the lung with the particulates. In addition, a fraction of the contaminants is released into the lung fluid and absorbed by the lung, and another fraction enters systemic circulation under the action of cell phagocytosis on particulates. Even if the release fraction, i.e., release bioaccessibility, is considered, the measurement faces many challenges. The present study highlights the factors influencing release bioaccessibility and the incorporation of inhalation bioaccessibility into the risk assessment of inhaled contaminants. Currently, there are three types of extraction techniques for simulated human lung fluids, including simple chemical solutions, sequential extraction techniques, and physiologically based techniques. The last technique generally uses three kinds of solution: Gamble's solution, Hatch's solution, and artificial lysosomal fluid, which are the most widely used physiologically based simulated human lung fluids. External factors such as simulated lung fluid composition, pH, extraction time, and sorption sinks can affect release bioaccessibility, whereas particle size and contaminant properties are important internal factors. Overall, release bioaccessibility is less used than bioaccessibility considering the deposition fraction when assessing the risk of contaminants in inhaled particulates. The release bioaccessibility measurement poses two main challenges: developing a unified, accurate, stable, simple, and systematic biologically based method, and validating the method through in-vivo assays.


Asunto(s)
Polvo , Material Particulado , Humanos , Exposición por Inhalación/análisis , Pulmón , Metales
8.
Artículo en Inglés | MEDLINE | ID: mdl-32784623

RESUMEN

BACKGROUND: Sugarcane workers in Central America experience a heavy burden of chronic kidney disease of unknown origin. We conducted a pilot study among worker proxies in Guatemala to characterize exposures to particulate matter, silica, heavy metals, and glyphosate, as well as to examine potential nephrotoxic exposures. METHODS: Air, soil, and ash samples were collected and analyzed using scanning electron microscopy, X-ray diffraction, inductively coupled plasma mass spectrometry, and an enzyme-linked immunosorbent assay. RESULTS: The average mass concentration for particulate matter (PM)2.5 and PM100 exposures were 360 µg/m3 (range: 32 to 1500 µg/m3) and 555 µg/m3 (range: 229 to 1170 µg/m3), respectively. The elemental composition of particles was largely silicon. The amount of crystalline silica was below 5 µg, yet the percentage of total silica was ~17% by weight. Putatively, the silica was in the amorphous form. Concentrations of aluminum and calcium ranged from 2-7 µg/m3. Glyphosate was not detectable in analyzed air samples but was detectable at concentrations ranging from 81-165 ppb in soil samples. CONCLUSION: Sugarcane workers are exposed to high concentrations of particulate matter. Future studies should investigate the potential role of silica, heavy metals, and agrochemicals in the etiology of chronic kidney disease in this population.


Asunto(s)
Enfermedades de los Trabajadores Agrícolas/epidemiología , Contaminantes Atmosféricos/efectos adversos , Monitoreo del Ambiente , Exposición por Inhalación/análisis , Saccharum , Enfermedades de los Trabajadores Agrícolas/inducido químicamente , Contaminantes Atmosféricos/análisis , Guatemala/epidemiología , Humanos , Exposición por Inhalación/efectos adversos , Material Particulado/análisis , Proyectos Piloto , Insuficiencia Renal Crónica/inducido químicamente , Insuficiencia Renal Crónica/epidemiología
9.
Artículo en Inglés | MEDLINE | ID: mdl-32615056

RESUMEN

Over the past decades, air pollution has become one of the critical environmental health issues in China. The present study aimed to evaluate links between ambient air pollution and the prevalence of type 2 diabetes mellitus (T2DM) and the levels of glycosylated hemoglobin (HbA1c). A multilevel linear and logistic regression was used to assess these associations among 7,770 participants aged ≥50 years from the WHO Study on global AGEing and adult health (SAGE) in China in 2007-2010. The average exposure to each of pollutants (particulate matter with an aerodynamic diameter of ≤10 µm/≤2.5 µm/≤1 µm [PM10/PM2.5/PM1] and nitrogen dioxide [NO2]) was estimated using a satellite-based spatial statistical model. In logistic models, a 10 µg/m3 increase in PM10 and PM2.5 was associated with increased T2DM prevalence (Prevalence Odds Ratio, POR: 1.27; 95% CI: 1.11, 1.45 and POR: 1.23; 95% CI: 1.03, 1.46). Similar increments in PM10, PM2.5, PM1 and NO2 were associated with increase in HbA1c levels of 1.8% (95% CI: 1.3, 2.3), 1.3% (95% CI: 1.1, 1.5), 0.7% (95% CI: 0.1, 1.3), and 0.8% (95% CI: 0.4, 1.2), respectively. In a large cohort of older Chinese adults, air pollution was liked to both higher T2DM prevalence and elevated HbA1c levels.


Asunto(s)
Envejecimiento/sangre , Contaminantes Atmosféricos/análisis , Diabetes Mellitus Tipo 2/epidemiología , Hemoglobina A Glucada/análisis , Exposición por Inhalación/análisis , Material Particulado/análisis , Adulto , Anciano , China/epidemiología , Estudios Transversales , Diabetes Mellitus Tipo 2/sangre , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Prevalencia , Organización Mundial de la Salud
10.
Artículo en Inglés | MEDLINE | ID: mdl-32610702

RESUMEN

Inflammatory allergic and nonallergic respiratory disorders are spreading worldwide and often coexist. The root cause is not clear. This review demonstrates that, from a biochemical point of view, it is ascribable to protons (H+) released into cells by exogenous and endogenous acids. The hypothesis of acids as the common cause stems from two considerations: (a) it has long been known that exogenous acids present in air pollutants can induce the irritation of epithelial surfaces, particularly the airways, inflammation, and bronchospasm; (b) according to recent articles, endogenous acids, generated in cells by phospholipases, play a key role in the biochemical mechanisms of initiation and progression of allergic-type reactions. Therefore, the intracellular acidification and consequent Ca2+ increase, induced by protons generated by either acid pollutants or endogenous phospholipases, may constitute the basic mechanism of the multimorbidity of these disorders, and environmental acidity may contribute to their spread.


Asunto(s)
Contaminantes Atmosféricos , Hipersensibilidad , Exposición por Inhalación/análisis , Enfermedades Respiratorias , Contaminantes Ambientales , Humanos , Exposición por Inhalación/estadística & datos numéricos
11.
Artículo en Inglés | MEDLINE | ID: mdl-32709123

RESUMEN

The adverse effects associated with exposure to flour dust have been known since the 1700s. The aim of the study was to assess the occupational exposure to flour dust in Italian facilities, identify the activities characterized by the highest exposure, and provide information to reduce workers' exposure. The study was performed in different facilities such as flourmills (n = 2), confectioneries (n = 2), bakeries (n = 24), and pizzerias (n = 2). Inhalable flour dust was assessed by personal and area samplings (n = 250) using IOM (Institute of Occupational Medicine) samplers. The results showed personal occupational exposure to flour dust over the American Conference of Governmental Industrial Hygiene (ACGIH) and the Scientific Committee on Occupational Exposure Limit (SCOEL) occupational limits (mean 1.987 mg/m3; range 0.093-14.055 mg/m3). The levels were significantly higher for dough makers in comparison to the dough formers and packaging area subjects. In four bakeries the industrial hygiene surveys were re-performed after some control measures, such as installation of a sleeve to the end of pipeline, a lid on the mixer tub or local exhaust ventilation system, were installed. The exposure levels were significantly lower than those measured before the introduction of control measures. The exposure level reduction was observed not only in the dough making area but also in all bakeries locals.


Asunto(s)
Contaminantes Ocupacionales del Aire , Polvo , Harina , Exposición Profesional , Salud Laboral , Contaminantes Ocupacionales del Aire/efectos adversos , Contaminantes Ocupacionales del Aire/análisis , Polvo/análisis , Harina/análisis , Humanos , Exposición por Inhalación/análisis , Exposición Profesional/análisis
12.
Chemosphere ; 260: 127451, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32673876

RESUMEN

This study aims to calculate deposition of PM2.5 -bound hazardous metals in different organs after inhalation of particulate matter for the Delhi (India), and to estimate risks to organs following inhalation. Bio-accessible fractions of three PM-associated carcinogenic metals (As, Pb &Cd) were calculated using the metal values in simulated lung fluids. Depositions of metals in different organs were calculated using an integrated model consists of HRT and PBPK models. The calculation indicates that the major or significant deposition of metal Pb occurs in tissues, such as bone, muscle and blood. Most of the depositions of Cd happens in lung whereas most of the depositions of As happens in lung, muscle and skin. Most of the deposition of studied metals was found in lung (45% for arsenic and 70% for cadmium of their bio -dissolved contents). The following order of depositions of metals in different tissues were found (from highest deposition to smallest deposition): As: Lung > muscle = liver; Pb: bone > blood > muscle; Cd: lung > intestine. The combined exposures of PM2.5 and its associated metals were found to give interaction-based hazard index greater than 1 for several months of the year, indicating a chance of health risk. Hazard quotient (HQ) <1 was seen for ingestion and dermal pathways, indicating no cause of concern. Findings indicate the need for doing periodic monitoring and estimating deposition doses and exposure risks of PM-associated metals to lungs and other organs for protecting human health.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Exposición por Inhalación/estadística & datos numéricos , Metales/análisis , Material Particulado/análisis , Arsénico/análisis , Fenómenos Biofísicos , Cadmio , Humanos , India , Exposición por Inhalación/análisis , Pulmón/metabolismo , Metales Pesados/análisis , Medición de Riesgo , Estaciones del Año
13.
Environ Pollut ; 266(Pt 2): 115209, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32688075

RESUMEN

In everyday life, people are exposed to different concentrations of airborne particles depending on the microenvironment where they perform their different activities. Such exposure can lead to high sub-micron particle doses. The received dose depends on particle concentration to which people are exposed (typically expressed in terms of number or surface area), time spent in each activity or microenvironment (time activity pattern) and amount of air inhaled (inhalation rate). To estimate an actual value of the received dose, all these parameters should be measured under real-life conditions; in fact, the concentrations should be measured on a personal scale (i.e. through a direct exposure assessment), whereas time activity patterns and inhalation rates specific to the activity performed should be considered. The difficulties in obtaining direct measurements of these parameters usually lead to adopt time activity patterns and inhalation rates already available in scientific literature for typical populations, and local outdoor particle concentrations measured with fixed monitoring stations and extrapolated for all the other microenvironments. To overcome these limitations, we propose a full-field method for estimating the received dose of a population sample, in which all the parameters (concentration levels, time activity patterns and inhalation rates) are measured under real-life conditions (also including the inhalation rates, that were evaluated on the basis of the measured heart rates). Specifically, 34 volunteers were continuously monitored for seven days and the data of sub-micron particle concentrations, activities performed, and inhalation rates were recorded. The received dose was calculated with the proposed method and compared with those obtained from different simplified methodologies that consider typical data of particle concentrations, time activity patterns and inhalation rates obtained from literature. The results show that, depending on the methodology used, the differences in the received daily dose can be significant, with a general underestimation of the most simplified method.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Humanos , Exposición por Inhalación/análisis , Tamaño de la Partícula , Material Particulado/análisis
14.
J Environ Public Health ; 2020: 7591263, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32508936

RESUMEN

Background: A few studies related to pediatric behavior have measured secondhand smoke exposure in children using valid objective biochemical markers. We aimed at investigating the associations between current and cumulative exposure to tobacco smoke, measured both subjectively and objectively, and behavioral problems in children. Methods: Subjects were 437 Japanese children, aged 3-6 years in 2006. Exposure to tobacco smoke was evaluated from a parent-administered questionnaire and urinary cotinine concentrations. The cotinine concentrations were measured using first-void morning urine by liquid chromatography-tandem mass spectrometry. Children's behaviors were assessed by the parent-completed Strengths and Difficulties Questionnaire. Results: After multiple adjustments for covariates, higher total difficulty scores of children were significantly associated with the larger number of cigarettes parents smoke, more smokers among cohabiters, and more pack-years of exposure to tobacco smoke from parents and cohabiters. The total difficulty scores were 8.72, 9.09, and 10.52, respectively, for children in the low, middle, and high tertiles of creatinine-corrected cotinine concentrations in urine (p=0.002, trend p=0.005). There was no substantial sex difference in the positive associations between passive smoking and the SDQ scores. Conclusions: Exposure to tobacco smoke in early childhood may be involved in the development of pediatric behavioral problems. The importance of reducing the exposure of children to tobacco smoke, particularly in the home, was further emphasized for the prevention of psychological and behavioral problems in childhood.


Asunto(s)
Exposición por Inhalación/efectos adversos , Problema de Conducta , Contaminación por Humo de Tabaco/efectos adversos , Biomarcadores/orina , Niño , Desarrollo Infantil , Preescolar , Cotinina/orina , Femenino , Humanos , Exposición por Inhalación/análisis , Japón/epidemiología , Masculino , Factores de Riesgo , Encuestas y Cuestionarios , Contaminación por Humo de Tabaco/análisis
15.
J Vis Exp ; (159)2020 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-32478724

RESUMEN

For toxicity testing of airborne particles, air-liquid interface (ALI) exposure systems have been developed for in vitro tests in order to mimic realistic exposure conditions. This puts specific demands on the cell culture models. Many cell types are negatively affected by exposure to air (e.g., drying out) and only remain viable for a few days. This limits the exposure conditions that can be used in these models: usually relatively high concentrations are applied as a cloud (i.e., droplets containing particles, which settle down rapidly) within a short period of time. Such experimental conditions do not reflect realistic long-term exposure to low concentrations of particles. To overcome these limitations the use of a human bronchial epithelial cell line, Calu-3 was investigated. These cells can be cultured at ALI conditions for several weeks while retaining a healthy morphology and a stable monolayer with tight junctions. In addition, this bronchial model is suitable for testing the effects of repeated exposures to low, realistic concentrations of airborne particles using an ALI exposure system. This system uses a continuous airflow in contrast to other ALI exposure systems that use a single nebulization producing a cloud. Therefore, the continuous flow system is suitable for repeated and prolonged exposure to airborne particles while continuously monitoring the particle characteristics, exposure concentration, and delivered dose. Taken together, this bronchial model, in combination with the continuous flow exposure system, is able to mimic realistic, repeated inhalation exposure conditions that can be used for toxicity testing.


Asunto(s)
Aire , Bronquios/patología , Células Epiteliales/patología , Exposición por Inhalación/análisis , Modelos Biológicos , Material Particulado/toxicidad , Pruebas de Toxicidad , Automatización , Técnicas de Cultivo de Célula , Línea Celular , Impedancia Eléctrica , Células Epiteliales/efectos de los fármacos , Humanos , L-Lactato Deshidrogenasa/metabolismo , Nanoestructuras/toxicidad
16.
J Environ Public Health ; 2020: 1561823, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32351580

RESUMEN

Particulate matter with an aerodynamic diameter of 10 µm or less (PM10) pollution poses a considerable threat to human health, and the first step in quantifying health impacts of human exposure to PM10 pollution is exposure assessment. Population-weighted exposure level (PWEL) estimation is one of the methods that provide a more refined exposure assessment as it includes the spatiotemporal distribution of the population into the pollution concentration estimation. This study assessed the population weighting effects on the estimated PM10 concentrations in Malaysia for years 2000, 2008, and 2013. Estimated PM10 annual mean concentrations with a spatial resolution of 5 kilometres retrieved from satellite data and population count obtained from the Gridded Population of the World version 4 (GPWv4) from the Centre for International Earth Science Information Network (CIESIN) were overlaid to generate the PWEL of PM10 for each state. The calculated PWEL of PM10 concentrations were then classified based on the World Health Organization (WHO) and the national Air Quality Guidelines (AQG) and interim targets (IT) for comparison. Results revealed that the annual mean PM10 concentrations in Malaysia ranged from 31 to 73 µg/m3 but became generally lower, ranging from 20 to 72 µg/m3 after population weighting, suggesting that the PM10 population exposure in Malaysia might have been overestimated. PWEL of PM10 distribution showed that the majority of the population lived in areas that complied with the national AQG, but were vulnerable to exposure level 3 according to the WHO AQG and IT, indicating that the population was nevertheless potentially exposed to significant health effects from long-term exposure to PM10 pollution.


Asunto(s)
Contaminantes Atmosféricos/análisis , Exposición por Inhalación/análisis , Material Particulado/análisis , Contaminación del Aire/análisis , Monitoreo del Ambiente , Humanos , Exposición por Inhalación/normas , Malasia , Tamaño de la Partícula , Material Particulado/química , Análisis Espacio-Temporal
17.
Toxicol Appl Pharmacol ; 400: 115041, 2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32428593

RESUMEN

Respiratory ailments have plagued occupational and public health communities exposed to World Trade Center (WTC) dust since the September 11, 2001 attack on the Twin Towers in Lower Manhattan. We proposed that these ailments were proposed to be induced by inhalation exposure to WTC particulate matter (WTCPM), that was released during the collapse of the buildings and its subsequent resuspension during cleanup. We investigated this hypothesis using both an in vitro and an in vivo mouse intranasal (IN) exposure models to identify the inflammatory potential of WTCPM with specific emphasis on respiratory and endothelial tissue responses. The in vitro exposure studies found WTCPM exposure to be positively correlated with cytotoxicity and increased NO2- production in both BEAS-2B pulmonary epithelial cells and THP-1 macrophage cells. The in vivo C57BL/6 mouse studies found significant increases in inflammatory markers including increases in polymorphonuclear neutrophil (PMN) influx into nasal and bronchoalveolar lavage fluids (NLF and BALF), as well as increased levels of total protein and cytokine/chemokines levels. Concurrently, NLF, BALF, and serum NO2- levels exhibited significant homeostatic temporal deviations as well as temporal myograohic aortic dysfunction in myography studies. Respiratory exposure to- and evidence -based retention of- WTCPM may have contributed to chronic systemic effects in exposed mice that r resembled to observed effects in WTCPM-exposed human populations. Collectively, these findings are reflective of WTCPM exposure and its effect(s) on respiratory and aortic tissues, highlighting potential dysfunctional pathways that may precipitate inflammatory events, while simultaneously altering homeostatic balances. The tight interplay between these balances, when chronically altered, may contribute to- or result in- chronically diseased pathological states.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Materiales de Construcción/toxicidad , Polvo/análisis , Endotelio Vascular/efectos de los fármacos , Exposición por Inhalación/efectos adversos , Neumonía/inducido químicamente , Contaminantes Atmosféricos/análisis , Animales , Aorta/efectos de los fármacos , Aorta/fisiopatología , Biomarcadores/sangre , Líquido del Lavado Bronquioalveolar/química , Líquido del Lavado Bronquioalveolar/citología , Líquido del Lavado Bronquioalveolar/inmunología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Materiales de Construcción/análisis , Endotelio Vascular/fisiopatología , Humanos , Exposición por Inhalación/análisis , Pulmón/efectos de los fármacos , Pulmón/inmunología , Ratones Endogámicos C57BL , Cavidad Nasal/efectos de los fármacos , Cavidad Nasal/inmunología , Ciudad de Nueva York , Ataques Terroristas del 11 de Septiembre , Células THP-1
18.
Ecotoxicol Environ Saf ; 200: 110774, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32460055

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants in atmosphere, which attracted more attentions due to their influence on human health. In this study, a national scale cancer risk (CR) assessment with atmospheric PAHs were conducted based on one year monitoring program at 11 cities across China. The annual mean concentrations of benzo[a]pyrene (BaP) and BaP equivalency (BaPeq) were 4.56 ± 7.78 ng/m3 and 8.45 ± 14.1 ng/m3, respectively, which were both higher than the new ambient air quality standards of China (GB 3095-2012, 1 ng/m3). Concentrations of BaP and BaPeq in northern Chinese cities were almost 2 times higher than those in southern Chinese cities. The CR values induced by the dermal contact exposure were two orders of magnitude higher than that by the inhalation exposure. Children and adults were the most sensitive age groups with the dermal contact exposure and the inhalation exposure to atmospheric PAHs, respectively. For the total CR values, 99.7% of its values were higher than the reference level of 10-6. No significant difference of the total CR values was observed between northern Chinese and southern Chinese cities for children and adults. In order to quantify the uncertainties of CR assessment, Monte Carlo Simulation was applied based on the specific distributions of the exposure factors cited from the Exposure Factors Handbook of Chinese Population. The results indicated that almost 90% probability of the total CR values were higher than 10-6, indicating potential cancer risk. Sensitive analysis indicated that atmospheric concentration, outdoor exposure fraction, particle amount adhered to skin, and cancer slope factor should be carefully considered in order to increase the accuracy of CR assessment with PAHs in atmosphere.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Atmósfera/química , Monitoreo del Ambiente/métodos , Exposición por Inhalación/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Adolescente , Adulto , Niño , China , Ciudades , Humanos , Exposición por Inhalación/efectos adversos , Método de Montecarlo , Neoplasias/epidemiología , Probabilidad , Medición de Riesgo
19.
Artículo en Inglés | MEDLINE | ID: mdl-32452753

RESUMEN

The large number of vehicles plying in roads is the main cause of traffic jam and air pollution in Hanoi. In this study, the vehicle density and shares of different vehicle types, the traffic flow velocity and roadside air pollutants concentrations were monitored in Chua Boc street, a typical arterial road in the city. The shares of the motorcycle, car and bus fleets in the total on-road traffic in the street were 78.4-87.3, 12.3-20.2 and 0.4-1.4%, respectively. The high density of vehicles caused traffic jam during rush hours and considerably reduced the vehicle speed. The traffic flow velocity during non-rush and rush hours was found to vary from 26.4-34.5 and 10.3-12.1 km/h, respectively. The average concentrations of PM10, PM2.5, SO2, NO2, CO and NMVOC during the rush hours were the following: 117.1 ± 8.5, 65.2 ± 10.6, 113.5 ± 10.9, 138.5 ± 16.0, 6792 ± 998 and 451 ± 71 µg/m3, respectively, which were about 1.9-2.6 times above the levels during non-rush hours. The decrease in vehicle speed during rush hours were strongly correlated with the increase in concentration of PM10 (R2 = 0.732), PM2.5 (R2 = 0.685), SO2 (R2 = 0.578), NO2 (R2 = 0.738), CO (R2 = 0.689) and NMVOC (R2 = 0.747). High levels of these toxic air pollutants in Hanoi city posed a high health risk to humans. Facemask use was more popular among the motorcycle commuters and pedestrians, especially during rush hours, than among the people working for extended time period alongside of the street.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Exposición por Inhalación/análisis , Material Particulado/análisis , Emisiones de Vehículos/análisis , Ciudades , Humanos , Medición de Riesgo , Vietnam
20.
Toxicol Lett ; 328: 52-60, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32320776

RESUMEN

Ambient PM2.5 was collected during the winter season from Taiyuan, Shanxi, China; Jinan, Shandong, China; and Sacramento, California, USA, and used to create PMSX, PMSD, and PMCA extracts, respectively. Time-lag experiments were performed to explore the in vivo and in vitro toxicity of the PM extracts. In vivo inflammatory lung responses were assessed in BALB/c mice using a single oropharyngeal aspiration (OPA) of PM extract or vehicle (CTRL) on Day 0. Necropsies were performed on Days 1, 2, and 4 post-OPA, and pulmonary effects were determined using bronchoalveolar lavage (BAL) and histopathology. On Day 1, BAL neutrophils were significantly elevated in all PM- versus CTRL-exposed mice, with PMCA producing the strongest response. However, histopathological scoring showed greater alveolar and perivascular effects in PMSX-exposed mice compared to all three other groups. By Day 4, BAL neutrophilia and tissue inflammation were resolved, similar across all groups. In vitro effects were examined in human HepG2 hepatocytes, and U937 cells following 6, 24, or 48 h of exposure to PM extract or DMSO (control). Luciferase reporter and quantitative polymerase chain reaction assays were used to determine in vitro effects on aryl hydrocarbon receptor (AhR) activation and gene transcription, respectively. Though all three PM extracts activated AhR, PMSX produced the greatest increases in AhR activation, and mRNA levels of cyclooxygenase-2, cytochrome P450, interleukin (IL)-8, and interleukin (IL)-1ß. These effects were assumed to result from a greater abundance of polycyclic aromatic hydrocarbons (PAHs) in PMSX compared to PMSD and PMCA.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Monitoreo del Ambiente/métodos , Pulmón/efectos de los fármacos , Pulmón/inmunología , Material Particulado/toxicidad , Receptores de Hidrocarburo de Aril/metabolismo , Animales , Líquido del Lavado Bronquioalveolar/citología , Líquido del Lavado Bronquioalveolar/inmunología , California , China , Citocinas/metabolismo , Células Hep G2 , Humanos , Exposición por Inhalación/efectos adversos , Exposición por Inhalación/análisis , Pulmón/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Tamaño de la Partícula , Receptores de Hidrocarburo de Aril/genética , Transcripción Genética/efectos de los fármacos , Células U937
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