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1.
Undersea Hyperb Med ; 46(4): 447-459, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31509901

RESUMO

Introduction: The mining and tunneling industries are historically associated with hazardous exposures that result in significant occupational health concerns. Occupational respiratory exposures causing pneumoconiosis and silicosis are of great concern, silicosis being non-curable. This work demonstrates that compressed-air workers (CAWs) performing tunnel hyperbaric interventions (HIs) may be at risk for hazards related to bentonite exposure, increasing the likelihood of developing harmful illnesses including cancer. Bentonite dust inhalation may result in respiratory levels of silica exceeding acceptable industrial hygiene standards. Methods: A qualitative observational exposure assessment was conducted on CAWs while they were performing their HI duties. This was followed by quantitative data collection using personal and area air sample techniques. The results were analyzed and interpreted using standard industrial hygiene principles and guidelines from NIOSH and OSHA. Results: Our work suggests bentonite dust exposure may be an emerging particulate matter concern among CAWs in the tunneling industry. Aerosolized bentonite particles may have potential deleterious effects that include pneumoconiosis and silicosis. Silicosis can result in the development of pulmonary carcinoma. Conclusions: The modern tunneling industry and required hyperbaric interventional tasks represent a potential public health and occupational concern for CAWs. This paper introduces the modern tunneling industry and the duties of CAWs, the hazardous environment in which they perform their duties, and describes the risks and potential harmful health effects associated with these hazardous exposures.


Assuntos
Bentonita/toxicidade , Ar Comprimido , Materiais de Construção/toxicidade , Poeira , Arquitetura de Instituições de Saúde , Exposição Ocupacional/efeitos adversos , Poluentes Ocupacionais do Ar/química , Poluentes Ocupacionais do Ar/toxicidade , Bentonita/química , Indústria da Construção , Materiais de Construção/análise , Segurança de Equipamentos , Filtração/instrumentação , Humanos , Pressão , Pesquisa Qualitativa , Dispositivos de Proteção Respiratória , Estados Unidos , United States Occupational Safety and Health Administration/normas
2.
J Perinat Med ; 47(7): 765-770, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31348763

RESUMO

Background Bisphenol A (BPA) is an estrogenic, endocrine-disrupting compound widely used in the industry. It is also a ubiquitous environmental pollutant. Its presence was confirmed in human fetuses, which results from maternal exposure during pregnancy. The mechanisms behind maternal-fetal transfer, and relationships between pregnant women and fetal exposures remain unclear. The aim of this study was to assess the impact of maternal exposure to BPA on the exposure of the fetus. Methods Maternal plasma and amniotic fluid samples were collected from 52 pregnant women undergoing amniocentesis for prenatal diagnosis of chromosomal abnormalities. BPA was measured by gas chromatography-mass spectrometry (GC-MS). The permeability factor - a ratio of fetal-to-maternal BPA concentration - was used as a measure delineating the transplacental transfer of BPA. Results The median concentration of maternal plasma BPA was 8 times higher than the total BPA concentration in the amniotic fluid (8.69 ng/mL, range: 4.3 ng/mL-55.3 ng/mL vs. median 1.03 ng/mL, range: 0.3 ng/mL-10.1 ng/mL). There was no direct relationship between the levels of BPA in maternal plasma and amniotic fluid levels. The permeability factor, in turn, negatively correlated with fetal development (birth weight) (R = -0.54, P < 0.001). Conclusion Our results suggest that the risk of fetal BPA exposure depends on placental BPA permeability rather than the levels of maternal BPA plasma concentration and support general recommendations to become aware and avoid BPA-containing products.


Assuntos
Líquido Amniótico/química , Compostos Benzidrílicos , Peso ao Nascer/efeitos dos fármacos , Troca Materno-Fetal , Fenóis , Placenta , Adulto , Poluentes Ocupacionais do Ar/efeitos adversos , Poluentes Ocupacionais do Ar/sangue , Poluentes Ocupacionais do Ar/química , Compostos Benzidrílicos/efeitos adversos , Compostos Benzidrílicos/sangue , Compostos Benzidrílicos/química , Exposição Ambiental/prevenção & controle , Estrogênios não Esteroides/efeitos adversos , Estrogênios não Esteroides/sangue , Estrogênios não Esteroides/química , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Exposição Materna/prevenção & controle , Permeabilidade , Fenóis/efeitos adversos , Fenóis/sangue , Fenóis/química , Placenta/metabolismo , Placenta/fisiopatologia , Gravidez , Segundo Trimestre da Gravidez
3.
Chemosphere ; 222: 549-555, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30721814

RESUMO

The present study focused on the enhanced biodegradation and mineralization of bisphenol A (BPA) as a toxic endocrine disrupting compound using peroxidase-mediated bioprocess under H2O2-infusion. The complete biodegradation of 100 mg/L BPA was achieved within 54 h reaction time at the optimum H2O2:BPA molar ratio of 10. BPA concentrations up to 100 mg/L had no inhibitory effect on the bacterial biomass at which a dehydrogenase activity of 9.1 µg TF/gbiomass and a peroxidase activity of 1.4 U/mL was obtained. The increase in biomass concentration from 90 to 450 mg/L improved the BPA biodegradation from 70.3% to 97.8% and its mineralization from 11.5% to 71.2% at the reaction time of 36 h. The highest BPA biodegradation rate was found to be 10.8 mg BPA/gbiomass. h. Accordingly, infusing H2O2 into the bioreactor stimulated the bacteria to produce peroxidase and allowed peroxidase-mediated enhanced biodegradation of BPA.


Assuntos
Poluentes Ocupacionais do Ar/química , Bactérias/enzimologia , Compostos Benzidrílicos/química , Biodegradação Ambiental , Reatores Biológicos/microbiologia , Minerais/química , Peroxidase/metabolismo , Fenóis/química
4.
Environ Sci Process Impacts ; 21(3): 497-505, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30788473

RESUMO

The bio-accessibility of 14 elements in welding fume particulate matter was investigated in 325 personal air samples collected during welding in two shipyards and one factory producing heavy machinery. The apparent solubility in a synthetic lung lining fluid (Hatch's solution) was used as proxy for the bio-accessibility. The Hatch solubility of the different elements was highly variable with a median < 1% for Al, Fe, Pb, Ti, between 4 and 6% for Co, Cr, Ni, V, W, between 13 and 27% for Cd, Cu, Mn, Zn, and 41% for Mo. For many elements, the solubility varied over a wide range of several tens of percent. The welding techniques used influenced the solubility of Co, Cr, Cu, Mn and V significantly. The plants investigated (i.e., the welded materials and used electrodes) had a significant influence on the solubility of Co, Cr, Cu, Mn, Mo, V and W. According to principal component analysis (PCA), the variation in solubility can be described by four components, which explain 69% of the variance. The first principal component mostly comprises elements that can predominantly occur as divalent cations, the second principal component elements often forming oxyanions. The principal components are independent of the absolute value of the Hatch solubility. The results of PCA indicate that the co-variation of Hatch solubility is mainly controlled by the most soluble compounds in contrast to the absolute value of apparent solubility, which is strongly influenced by the distribution of the elements between compounds with different equilibrium solubilities. The observed large variability and the significant differences between welding techniques and plants clearly show that the bio-accessibility cannot be obtained from the literature but has to be studied experimentally at each location of interest.


Assuntos
Poluentes Ocupacionais do Ar/análise , Gases/análise , Exposição Ocupacional/análise , Material Particulado/análise , Soldagem , Poluentes Ocupacionais do Ar/química , Disponibilidade Biológica , Gases/química , Humanos , Masculino , Metalurgia , Material Particulado/química , Federação Russa , Solubilidade
5.
Toxicol Appl Pharmacol ; 362: 67-76, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30393145

RESUMO

Calcium carbonate rock dust (RD) is used in mining to reduce the explosivity of aerosolized coal. During the dusting procedures, potential for human exposure occurs, raising health concerns. To improve RD aerosolization, several types of anti-caking surface treatments exist. The aim of the study was to evaluate cytotoxicity of four respirable RD samples: untreated/treated limestone (UL/TL), untreated/treated marble (UM/TM), and crystalline silica (SiO2) as a positive control in A549 and THP-1 transformed human cell lines. Respirable fractions were generated and collected using FSP10 high flow-rate cyclone samplers. THP-1 cells were differentiated with phorbol-12-myristate-13-acetate (20 ng/ml, 48 h). Cells were exposed to seven different concentrations of RD and SiO2 (0-0.2 mg/ml). RD caused a slight decrease in viability at 24 or 72 h post-exposure and were able to induce inflammatory cytokine production in A549 cells, however, with considerably less potency than SiO2. In THP-1 cells at 24 h, there was significant dose-dependent lactate dehydrogenase, inflammatory cytokine and chemokine release. Caspase-1 activity was increased in SiO2- and, on a lesser scale, in TM- exposed cells. To test if the increased toxicity of TM was uptake-related, THP-1 cells were pretreated with Cytochalasin D (CytD) or Bafilomycin A (BafA), followed by exposure to RD or SiO2 for 6 h. CytD blocked the uptake and significantly decreased cytotoxicity of all particles, while BafA prevented caspase-1 activation but not cytotoxic effects of TM. Only TM was able to induce an inflammatory response in THP-1 cells, however it was much less pronounced compared to silica.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Carbonato de Cálcio/toxicidade , Poeira , Ácidos Esteáricos/toxicidade , Células A549 , Poluentes Ocupacionais do Ar/química , Carbonato de Cálcio/química , Sobrevivência Celular/efeitos dos fármacos , Humanos , Ácidos Esteáricos/química , Células THP-1
6.
Chem Res Toxicol ; 31(11): 1172-1184, 2018 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-30362728

RESUMO

Epidemiological studies in chromate production have established hexavalent chromium as a potent lung carcinogen. Inhalation of chromium(VI) most often occurs in mixtures with other metals as among stainless steel welders, which is the largest occupational group with Cr(VI) exposure. Surprisingly, carcinogenicity of Cr(VI)-containing welding fumes is moderate and not consistently higher than that of Cr-free welding. Here, we investigated interactions between chromate and three other metal ions [Fe(III), Mn(II), Ni(II)] that are typically released from stainless steel welding particles. In human lung epithelial cells with physiological levels of ascorbate and glutathione, Cr(VI) was by far the most cytotoxic metal in single exposures. Coexposure with Fe(III) suppressed cytotoxicity and genotoxicity of Cr(VI), which resulted from a severe inhibition of Cr uptake by cells and required extracellular ascorbate/glutathione. Chemically, detoxification of Cr(VI) occurred via its rapid extracellular reduction by Fe(II) that primarily originated from ascorbate-reduced Fe(III). Glutathione was a significant contributor to reduction of Cr(VI) by Fe only in the presence of ascorbate. We further found that variability in Cr(VI) metabolism among common cell culture media was caused by their different Fe content. Ni(II) and Mn(II) had no detectable effects on metabolism, cellular uptake or cytotoxicity of Cr(VI). The main biological findings were confirmed in three human lung cell lines, including stem cell-like and primary cells. We discovered extracellular detoxification of carcinogenic chromate in coexposures with Fe(III) ions and identified the underlying chemical mechanism. Our findings established an important case when exposure to mixtures causes inactivation of a potent human carcinogen.


Assuntos
Cromo/química , Gases/química , Ferro/química , Metais/química , Soldagem , Poluentes Ocupacionais do Ar/química , Poluentes Ocupacionais do Ar/toxicidade , Ácido Ascórbico/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cromo/metabolismo , Cromo/toxicidade , Dano ao DNA/efeitos dos fármacos , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Glutationa/química , Humanos , Oxirredução
7.
Artigo em Inglês | MEDLINE | ID: mdl-29875328

RESUMO

BACKGROUND: The characteristics of aerosol, in particular particle size and chemical composition, can have an impact on human health. Particle size distribution and chemical composition is a necessary parameter in occupational exposure assessment conducted in order to understand possible health effects. The aim of this study was to characterize workplace airborne particulate matter in a metallurgical setting by synergistically using two different approaches; Methodology: Analysis of inhalable fraction concentrations through traditional sampling equipment and ultrafine particles (UFP) concentrations and size distribution was conducted by an Electric Low-Pressure Impactor (ELPI+™). The determination of metallic elements (ME) in particles was carried out by inductively coupled plasma mass spectrometry; Results: Inhalable fraction and ME concentrations were below the limits set by Italian legislation and the American Conference of Governmental Industrial Hygienists (ACGIH, 2017). The median of UFP was between 4.00 × 104 and 2.92 × 105 particles/cm³. ME concentrations determined in the particles collected by ELPI show differences in size range distribution; Conclusions: The adopted synergistic approach enabled a qualitative and quantitative assessment of the particles in steelmaking factories. The results could lead to a better knowledge of occupational exposure characterization, in turn affording a better understanding of occupational health issues due to metal fumes exposure.


Assuntos
Poluentes Ocupacionais do Ar , Monitoramento Ambiental , Metais/química , Exposição Ocupacional/análise , Tamanho da Partícula , Material Particulado , Aerossóis/análise , Poluentes Ocupacionais do Ar/análise , Poluentes Ocupacionais do Ar/química , Humanos , Itália , Metalurgia , Metais/análise , Exposição Ocupacional/normas , Material Particulado/análise , Material Particulado/química
8.
Ann Agric Environ Med ; 25(2): 262-267, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29936814

RESUMO

OBJECTIVE: The aim of the study was to assess the impact of a fattening season on the level of airborne chemical and microbial pollutants in the pig fattening house. MATERIAL AND METHODS: Evaluation of the air composition as well as the microbiological air quality were made during 2 series, i.e. in the summer and winter period of fattening. Airborne gaseous pollutants were analyzed by gas (organic compounds) and liquid (inorganic compounds) chromatography methods. Air microbial contamination was determined in compliance with the Polish Standard PN-EN 13098:2007. RESULTS: The air/gas composition in the pig unit showed that irrespective of the fattening season, the level of determined pollutants - especially ammonia, volatile organic compounds (VOCs), including methanethiol and total dust - could have an adverse effect on the health of swine facility workers. The investigated pig building was found to be a source of chemical pollutants as well as biological agents. The total bacterial count in 1 m3 of air was 3.6×106 and 4.6×106 cfu, during the winter and summer periods of fattening, respectively. Gram-positive cocci predominated in both seasons. In the winter, fungi of the Trichoderma genus were represented equally often. In the summer period, up to 90% of the isolated fungus was Aspergillus spp. CONCLUSIONS: Workers engaged in swine rearing and production are occupationally exposed not only to a high concentration of microbial contamination, but also to irritating and odorogenous volatile compounds. Thus, activities directed at the promotion of health prevention strategies, as well as effective guidelines for safe and hygienic animal housing, should be implemented.


Assuntos
Microbiologia do Ar , Poluentes Ocupacionais do Ar/química , Criação de Animais Domésticos , Poluentes Ambientais/química , Exposição Ocupacional/análise , Adulto , Doenças dos Trabalhadores Agrícolas/etiologia , Poluentes Ocupacionais do Ar/efeitos adversos , Animais , Poluentes Ambientais/efeitos adversos , Fazendeiros , Feminino , Abrigo para Animais , Humanos , Masculino , Exposição Ocupacional/efeitos adversos , Estações do Ano , Suínos/crescimento & desenvolvimento , Recursos Humanos , Adulto Jovem
9.
J Vis Exp ; (135)2018 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-29782003

RESUMO

Traditional methods of identifying fungal exposures in occupational environments, such as culture and microscopy-based approaches, have several limitations that have resulted in the exclusion of many species. Advances in the field over the last two decades have led occupational health researchers to turn to molecular-based approaches for identifying fungal hazards. These methods have resulted in the detection of many species within indoor and occupational environments that have not been detected using traditional methods. This protocol details an approach for determining fungal diversity within air samples through genomic DNA extraction, amplification, sequencing, and taxonomic identification of fungal internal transcribed spacer (ITS) regions. ITS sequencing results in the detection of many fungal species that are either not detected or difficult to identify to species level using culture or microscopy. While these methods do not provide quantitative measures of fungal burden, they offer a new approach to hazard identification and can be used to determine overall species richness and diversity within an occupational environment.


Assuntos
Poluentes Ocupacionais do Ar/química , DNA Fúngico/genética , Análise de Sequência de DNA/métodos
10.
Surg Endosc ; 32(10): 4290-4298, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29770884

RESUMO

BACKGROUND: Generation of smoke is inevitable during surgical procedures. Some volatile organic compounds (VOCs) in surgical smoke are known to be strong carcinogens. We used a prototype of a multi-layered complex filter in an attempt to eliminate VOCs. METHODS: From June 2015 to July 2015, 20 patients underwent transperitoneal laparoscopic nephrectomy for renal cell carcinoma. Smoke (pre-filter) was collected 20 min after the electrocautery device was first used during the surgery, by the direct collection method, with a 5-L Tedlar® gas-sampling bag. Twenty and 120 min after the filter was applied, smoke (post-filter) was again collected using the same method. The sample was analyzed by gas chromatography and mass spectrography. The cancer risk and hazard quotient were analyzed based on US Environmental Protection Agency guidelines. RESULTS: Twenty patients with a median age of 54.5 (30-80) years were enrolled in the study. Eighteen VOCs were detected using the Japanese indoor air standards mix analysis. The total elimination rate of the VOCs was 86.49 ± 2.83%. The post-filter (120 min) cancer risk (mean ± standard deviation) reduced to a negligible level for benzene, ethylbenzene, and styrene except 1,2-dichloroethane. The post-filter (120 min) hazard quotient for each compound decreased to levels posing a negligible risk for acetone, hexane, benzene, toluene, p-xylene, o-xylene, and styrene. CONCLUSION: Strong carcinogens, such as 1,2-dichloroethane, benzene, and ethylbenzene, were eliminated by more than 85% by using this activated carbon fiber filter and the risks from these compounds decreased to an almost negligible level. We suggest using every measure, including these filters, to protect the health of operating room personnel.


Assuntos
Poluentes Ocupacionais do Ar/química , Fibra de Carbono , Carcinógenos , Filtração/instrumentação , Laparoscopia/efeitos adversos , Exposição Ocupacional/prevenção & controle , Fumaça/prevenção & controle , Compostos Orgânicos Voláteis , Adulto , Idoso , Idoso de 80 Anos ou mais , Eletrocoagulação , Humanos , Laparoscopia/instrumentação , Pessoa de Meia-Idade , Exposição Ocupacional/análise , Fumaça/análise
12.
J Anal Toxicol ; 42(5): 360-364, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29462320

RESUMO

Storage of drug-based evidence inside sealed safes may allow chemical vapors to accumulate, creating concerns of drug exposure by inhalation, or the possibility of cross-contamination of drug evidence. Air samples were taken from inside eight drug safes and one small storage room at nine city and country police stations, as well as a large centralized drug evidence storage vault, in New South Wales (NSW), Australia. Sorbent tubes containing charcoal were used to determine whether any drug residues could be detected in the air, and to identify the types of chemicals present. Carbon traps were extracted and analyzed by LC-MS-MS for a suite of 22 licit and illicit drug residues and 2 metabolites. Carbon traps and SPME fibers were also analyzed by GC-MS for general volatile organic compound (VOC) residues. No detectable drug residues, either as airborne dust or vapor, were found in the safes, the storage room or the large central repository vault. No drugs were detected in any of the 34 urine samples collected at 8 of the 10 sampling locations, while only one of the five hair samples was positive for cocaine (9 pg/mg) provided by police exhibit officers at 3 of the 10 sampling locations. VOC analysis identified a variety of solvents associated with drug manufacture, plasticisers, personal care products and volatiles associated with plants such as cannabis. The results indicate that strong chemical odours emanating from drug safes are unlikely to be drug residues due to low volatility of drugs, and are more likely VOCs associated with their manufacture or from plant growing operations. Consideration should be given to the quality of air flow in rooms in which safes are housed and the use of air filtering inside safes to reduce the likelihood of VOC accumulation, and therefore the risk of human exposure.


Assuntos
Poluentes Ocupacionais do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Polícia , Medidas de Segurança , Compostos Orgânicos Voláteis/análise , Local de Trabalho , Adulto , Poluentes Ocupacionais do Ar/química , Poluentes Ocupacionais do Ar/toxicidade , Poluentes Ocupacionais do Ar/urina , Poluição do Ar em Ambientes Fechados/efeitos adversos , Cromatografia Líquida de Alta Pressão , Armazenamento de Medicamentos , Monitoramento Ambiental , Cabelo/química , Humanos , /toxicidade , Exposição por Inalação/efeitos adversos , Exposição por Inalação/prevenção & controle , New South Wales , Plastificantes/análise , Plastificantes/química , Plastificantes/toxicidade , Medição de Risco , Microextração em Fase Sólida , Solventes/análise , Solventes/química , Solventes/toxicidade , Espectrometria de Massas em Tandem , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/toxicidade , Compostos Orgânicos Voláteis/urina , Volatilização
13.
Regul Toxicol Pharmacol ; 92: 251-267, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29233769

RESUMO

Talc has been used historically in a wide range of industrial applications and consumer products. The composition and purity of talc used for industrial purposes can vary greatly depending on the source and may contain asbestos minerals. The developing science associated with the health risks of asbestos had an effect on the talc industry throughout the 20th century. This review presents a detailed analysis of the evolution of regulatory standards impacting the use of industrial talc in the U.S. from the early 20th century through the 1990s. While it was recognized by the 1930s that airborne exposures to talc dust at high concentrations could cause lung disease, it was not until later that concerns were raised about the health risks associated with potential occupational exposures to asbestos from industrial talc. Regulatory agencies adopted occupational standards for industrial talc in the early 1970s, but the terminology used to define and characterize talc and other associated minerals varied between agencies. In addition, the complex and varying mineralogy of industrial talc led to inconsistent and imprecise interpretation of studies concerning health risk and occupational health standards among individual agencies.


Assuntos
Exposição Ocupacional/análise , Talco/efeitos adversos , Talco/química , Poluentes Ocupacionais do Ar/química , Animais , Asbestos/efeitos adversos , Asbestos/química , Poeira/análise , Humanos , Indústrias , Saúde do Trabalhador
14.
J Occup Environ Hyg ; 15(2): 152-156, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29157175

RESUMO

There is interest in the bioaccessible metal components of aerosols, but this has been minimally studied because standardized sampling and analytical methods have not yet been developed. An interlaboratory study (ILS) has been carried out to evaluate a method for determining the water-soluble component of realistic welding fume (WF) air samples. Replicate samples were generated in the laboratory and distributed to participating laboratories to be analyzed according to a standardized procedure. Within-laboratory precision of replicate sample analysis (repeatability) was very good. Reproducibility between laboratories was not as good, but within limits of acceptability for the analysis of typical aerosol samples. These results can be used to support the development of a standardized test method.


Assuntos
Aerossóis/análise , Poluentes Ocupacionais do Ar/análise , Metais/análise , Soldagem , Poluentes Ocupacionais do Ar/química , Monitoramento Ambiental/métodos , Metais/química , Reprodutibilidade dos Testes
15.
Toxicol Sci ; 160(1): 47-56, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29036659

RESUMO

Many substances in workplace do not have occupational exposure limits. The threshold of toxicological concern (TTC) principle is part of the hierarchy of approaches useful in occupational health risk assessment. The aim of this study was to derive occupational TTCs (OTTCs) reflecting the airborne concentrations below which no significant risk to workers would be anticipated. A reference dataset consisting of the 8-h threshold limit values-Time-Weighted Average for 280 organic substances was compiled. Each substance was classified into low (class I), intermediate (class II), or high (class III) hazard categories as per Cramer rules. For each chemical, n-octanol:water partition coefficient and vapor pressure along with the molecular weight were used to predict the blood:air partition coefficient. The blood:air partition coefficient along with data on water solubility and ventilation rate allowed the prediction of pulmonary retention factor and absorbed dose in workers. For each Cramer class, the distribution of the predicted doses was analyzed to identify the various percentile values corresponding to the OTTC. Accordingly, for Cramer classes I-III, the OTTCs derived in this study correspond to 0.15, 0.0085, and 0.006 mmol/d, respectively, at the 10th percentile level, while these values were 1.5, 0.09 and 0.03 mmol/d at the 25th percentile level. The proposed OTTCs are not meant to replace the traditional occupational exposure limits, but can be used in data-poor situations along with exposure estimates to support screening level risk assessment and prioritization.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Exposição por Inalação/efeitos adversos , Doenças Profissionais/induzido quimicamente , Exposição Ocupacional/efeitos adversos , Saúde do Trabalhador , Compostos Orgânicos/efeitos adversos , Poluentes Ocupacionais do Ar/química , Poluentes Ocupacionais do Ar/classificação , Bases de Dados Factuais , Relação Dose-Resposta a Droga , Humanos , Nível de Efeito Adverso não Observado , Compostos Orgânicos/química , Compostos Orgânicos/classificação , Medição de Risco , Níveis Máximos Permitidos , Local de Trabalho
16.
Ecotoxicol Environ Saf ; 144: 445-449, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28666218

RESUMO

The aim of this study was to evaluate benzene, toluene, ethylbenzene, and xylene (BTEX) exposure among workers at four stations of a major oil distribution company. Personal BTEX exposure samples were collected over working shift (8h) for 50 workers at four stations of a major oil distribution company in Iran. Measured mean values for workers across four sites were benzene (2437, 992, 584, and 2788µg/m3 respectively), toluene (4415, 2830, 1289, and 9407µg/m3), ethylbenzene (781, 522, 187, and 533µg/m3), and xylene (1134, 678, 322, and 525µg/m3). The maximum mean concentration measured across sites for benzene was 2788µg/m3 (Station 4), toluene was 9407µg/m3 (Station 4), ethylbenzene was 781µg/m3 (Station 1) and xylene was 1134µg/m3 (Station 1). The 8h averaged personal exposure benzene concentration exceeded the recommended value of 1600µg/m3 established by the Iranian Committee for Review and Collection of Occupational Exposure Limit and American Conference of Governmental Industrial Hygienists. Mean values for excess lifetime cancer risk for exposure to benzene were then calculated across workers at each site. Estimates of excess risk ranged from 1.74 ± 4.05 (Station 4) to 8.31 ± 25.81 (Station 3). Risk was assessed by calculation of hazard quotients and hazard indexes, which indicated that xylene and particularly benzene were the strongest contributors. Tanker loading was the highest risk occupation at these facilties. Risk management approaches to reducing exposures to BTEX compounds, especially benzene, will be important to the health of workers in Iran.


Assuntos
Poluentes Ocupacionais do Ar/análise , Monitoramento Ambiental/métodos , Exposição Ocupacional/análise , Petróleo/análise , Poluentes Ocupacionais do Ar/química , Humanos , Irã (Geográfico) , Neoplasias/induzido quimicamente , Exposição Ocupacional/efeitos adversos , Medição de Risco , Local de Trabalho/normas
17.
Inhal Toxicol ; 29(5): 227-238, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28722486

RESUMO

Manganese (Mn) is a toxic heavy metal exposing workers in various occupational settings and causing, among others, nervous system damage. Metal fumes of welding, a typical source of Mn exposure, contain a complex mixture of metal oxides partly in nanoparticle form. As toxic effects of complex substances cannot be sufficiently understood by examining its components separately, general toxicity and functional neurotoxicity of a main pathogenic welding fume metal, Mn, was examined alone and combined with iron (Fe) and chromium (Cr), also frequently found in fumes. Oxide nanoparticles of Mn, Mn + Fe, Mn + Cr and the triple combination were applied, in aqueous suspension, to the trachea of young adult Wistar rats for 4 weeks. The decrease of body weight gain during treatment, caused by Mn, was counteracted by Fe, but not Cr. At the end of treatment, spontaneous and evoked cortical electrical activity was recorded. Mn caused a shift to higher frequencies, and lengthened evoked potential latency, which were also strongly diminished by co-application of Fe only. The interaction of the metals seen in body weight gain and cortical activity were not related to the measured blood and brain metal levels. Fe might have initiated protective, e.g. antioxidant, mechanisms with a more general effect.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Intoxicação do Sistema Nervoso por Metais Pesados/patologia , Manganês/toxicidade , Nanopartículas Metálicas/toxicidade , Soldagem , Administração por Inalação , Poluentes Ocupacionais do Ar/química , Animais , Esquema de Medicação , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Traqueia/citologia , Ganho de Peso
18.
J Occup Environ Hyg ; 14(7): 510-522, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28406371

RESUMO

Nano-enabled construction products have entered into commerce. There are concerns about the safety of manufactured nanomaterials, and exposure assessments are needed for a more complete understanding of risk. This study assessed potential inhalation exposure to ZnO nanoparticles during spray application and power sanding of a commercially available wood sealant and evaluated the effectiveness of local exhaust ventilation in reducing exposure. A tradesperson performed the spraying and sanding inside an environmentally-controlled chamber. Dust control methods during sanding were compared. Filter-based sampling, electron microscopy, and real-time particle counters provided measures of exposure. Airborne nanoparticles above background levels were detected by particle counters for all exposure scenarios. Nanoparticle number concentrations and particle size distributions were similar for sanding of treated versus untreated wood. Very few unbound nanoparticles were detected in aerosol samples via electron microscopy, rather nano-sized ZnO was contained within, or on the surface of larger airborne particles. Whether the presence of nanoscale ZnO in these aerosols affects toxicity merits further investigation. Mass-based exposure measurements were below the NIOSH Recommended Exposure Limit for Zn, although there are no established exposure limits for nanoscale ZnO. Local exhaust ventilation was effective, reducing airborne nanoparticle number concentrations by up to 92% and reducing personal exposure to total dust by at least 80% in terms of mass. Given the discrepancies between the particle count data and electron microscopy observations, the chemical identity of the airborne nanoparticles detected by the particle counters remains uncertain. Prior studies attributed the main source of nanoparticle emissions during sanding to copper nanoparticles generated from electric sander motors. Potentially contrary results are presented suggesting the sander motor may not have been the primary source of nanoparticle emissions in this study. Further research is needed to understand potential risks faced by construction workers exposed to mixed aerosols containing manufactured nanomaterials. Until these risks are better understood, this study demonstrates that engineering controls can reduce exposure to manufactured nanomaterials; doing so may be prudent for protecting worker health.


Assuntos
Poluentes Ocupacionais do Ar/análise , Nanopartículas/análise , Exposição Ocupacional/análise , Óxido de Zinco/análise , Poluentes Ocupacionais do Ar/química , Materiais de Construção , Monitoramento Ambiental/métodos , Humanos , Exposição por Inalação/análise , Microscopia Eletrônica de Varredura , Nanopartículas/química , Nanopartículas/ultraestrutura , Tamanho da Partícula , Ventilação/métodos , Madeira
19.
Toxicol Pathol ; 45(3): 389-401, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28136187

RESUMO

This review analyzes the published data on cases of pulmonary alveolar proteinosis (PAP) in workers inhaling crystalline aluminum, indium, silicon, and titanium particles and possible sequelae, that is, inflammation and fibrosis, and compares these findings with those from animal experiments. In inhalation studies in rodents using crystalline indium and gallium compounds, pronounced PAP followed by inflammation and fibrosis down to very low concentration ranges have been reported. Crystalline aluminum, silicon, and titanium compounds also induced comparable pulmonary changes in animals, though at higher exposure levels. Laboratory animal species appear to react to the induction of PAP with varying degrees of sensitivity. The sensitivity of humans to environmental causes of PAP seems to be relatively low. Up to now, no cases of PAP, or other pulmonary diseases in humans, have been described for gallium compounds. However, a hazard potential can be assumed based on the results of animal studies. Specific particle properties, responsible for the induction of PAP and its sequelae, have not been identified. This review provides indications that, both in animal studies and in humans, PAP is not often recognized due to the absence of properly directed investigation or is concealed behind other forms of lung pathology.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Doenças Profissionais/induzido quimicamente , Material Particulado/toxicidade , Proteinose Alveolar Pulmonar/induzido quimicamente , Fibrose Pulmonar/induzido quimicamente , Poluentes Ocupacionais do Ar/química , Animais , Humanos , Exposição por Inalação/efeitos adversos , Exposição por Inalação/análise , Doenças Profissionais/patologia , Tamanho da Partícula , Material Particulado/química , Proteinose Alveolar Pulmonar/patologia , Fibrose Pulmonar/patologia , Especificidade da Espécie
20.
Gig Sanit ; 96(2): 155-7, 2017.
Artigo em Russo | MEDLINE | ID: mdl-29446602

RESUMO

The toxic properties of 2-formylphenoxyethane acid for hygienic standardization in the air of working zone were studied. The substance in the dose equal of DL introduced into the stomach for male rats, male and female mice accounted for 5354, 3698 and 4322 mg/kg. It refers to moderately hazardous substances. No significant differences in species and gender sensitivity of animals to the substance were noted. It possesses a strong ability to cumulation: C is 2.9. It has a marked irritating effect to the mucous membranes of eyes and the moderate one - to the skin. Ithas a toxic effect on the liver, kidneys, central nervous system. The threshold of acute inhalation effect (Lim) is 120.3 mg/m. At Lim level it has no irritating effect on the respiratory tract. The tentative safe exposure level of 2-formylphenoxyethane acid in the air of working zone is 1 mg/m.


Assuntos
Poluentes Ocupacionais do Ar , Amiodarona/química , Doenças Profissionais , Exposição Ocupacional , Tecnologia Farmacêutica , Poluentes Ocupacionais do Ar/análise , Poluentes Ocupacionais do Ar/química , Animais , Antiarrítmicos/química , Modelos Animais de Doenças , Indústria Farmacêutica/normas , Humanos , Concentração Máxima Permitida , Doenças Profissionais/induzido quimicamente , Doenças Profissionais/prevenção & controle , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Exposição Ocupacional/normas , Ratos , Padrões de Referência , Tecnologia Farmacêutica/métodos , Tecnologia Farmacêutica/normas , Testes de Toxicidade/métodos
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