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BackgroundAlthough major concerns exist regarding the potential consequences of human exposures to nanoscale carbon black (CB) particles, limited human toxicological data is currently available. The purpose of this study was to evaluate if nanoscale CB particles could be responsible, at least partially, for the altered lung function and inflammation observed in CB workers exposed to nanoscale CB particles.MethodsScanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Brunauer-Emmett-Teller were used to characterize CB. Eighty-one CB-exposed male workers and 104 non-exposed male workers were recruited. The pulmonary function test was performed and pro-inflammatory cytokines were evaluated. To further assess the deposition and pulmonary damage induced by CB nanoparticles, male BALB/c mice were exposed to CB for 6 hours per day for 7 or 14 days. The deposition of CB and the pathological changes of the lung tissue in mice were evaluated by paraffin sections and TEM. The cytokines levels in serum and lung tissue of mice were evaluated by ELISA and immunohistochemical staining (IHC).ResultsSEM and TEM images showed that the CB particles were 30 to 50 nm in size. In the CB workplace, the concentration of CB was 14.90 mg/m3. Among these CB particles, 50.77% were less than 0.523 micrometer, and 99.55% were less than 2.5 micrometer in aerodynamic diameter. The reduction of lung function parameters including FEV1%, FEV/FVC, MMF%, and PEF% in CB workers was observed, and the IL-1β, IL-6, IL-8, MIP-1beta, and TNF- alpha had 2.86-, 6.85-, 1.49-, 3.35-, and 4.87-folds increase in serum of CB workers, respectively. In mice exposed to the aerosol CB, particles were deposited in the lung. The alveolar wall thickened and a large amount of inflammatory cells were observed in lung tissues after CB exposure. IL-6 and IL-8 levels were increased in both serum and lung homogenate.ConclusionsThe data strongly suggests that nanoscale CB particles could be responsible for the lung function reduction and pro-inflammatory cytokines secretion in CB workers. These results, therefore, provide the first evidence of a link between human exposure to CB and long-term pulmonary effects.Electronic supplementary materialThe online version of this article (doi:10.1186/s12989-014-0073-1) contains supplementary material, which is available to authorized users.

SummaryData were collected from managers in 24 nations/territories on work locus of control (LOC), individualism±collectivism (I±C), and well-being (job satisfaction, absence of psychological strain, and absence of physical strain). There were signi®cant mean differences across samples on all ®ve of these measures, and consistent with our hypothesis, at the ecological or sample mean level well-being was associated with an internal locus of control. However, contrary to our hypothesis, well-being was not associated with I±C, despite a strong correlation between I±C and LOC. Findings at the ecological level were consistent with the literature concerning the salutary effects of control on well-being.

La présente étude examine les effets directs et modérateurs des stratégies de défense (contrôle et support) et de la perception de contrôle au travail (extérieure) sur des relations stresseur-tension entre des gestionnaires de la grande Chine (la République populaire de Chine, Hong Kong, et Taiwan). Les données ont été recueillies, via un questionnaire autoadministré, auprès de 876 gestionnaires soit 249 (164 hommes, 85 femmes) en République populaire de Chine, 280 à Hong Kong (159 hommes, 120 femmes, 1 non classifié), et 347 (191 hommes, 151 femmes, 5 non classifiés) au Taiwan. Des effets directs et modérateurs pour les stratégies de défense et pour la perception de contrôle ont été démontrés pour quelques relations stresseur-tension dans les divers échantillons étudiés. self-administered survey method was employed to collect data from 249 (164 male, 85 female) managers in the PRC, 280 (159 male, 120 female, 1 unclassified) managers in Hong Kong, and 347 (191 male, 151 female, 5 unclassified) managers in Taiwan. The direct and moderator effects of control coping, support coping, and work locus of control on some stressor-strain relationships were demonstrated in the studied samples.

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