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Given the results of experimental studies, occupational or environmental exposures to manufactured nanoparticles or to unintentionally produced ultrafine particles may result in health effects or diseases in humans. In this review, we synthesize published data of experimental studies on the distribution of inhaled nanoparticles and the first case reports to discuss the potential usefulness of their biological monitoring for clinical purposes. Toxicokinetic studies suggest that nanoparticles may be absorbed predominantly by respiratory and oral routes with possible systemic translocation, leading to accumulation in the peripheral organs or excretion in feces or urine. Some methods used in these studies may be applied successfully in retrospective evaluation of exposure or in follow-up of occupational exposure in the workplace. Biological monitoring of nanoparticles should be based on imaging methods that are essential to confirm their presence and to characterize them in tissue associated with analytical quantitative methods. The first case reports reviewed emphasize the urgent need for the development of standardized procedures for the preparation and analysis of biological samples with a view to characterizing and quantifying nanoparticles.

The aim of this study was to investigate the hypothesis of an increased risk of pleural mesothelioma due to co-exposure to asbestos and refractory ceramic fibres (RCF) compared to asbestos exposure alone. Males were selected from a French case-control study conducted in 1987-1993 and from the French National Mesothelioma Surveillance Program in 1998-2006. Two population controls were frequency matched to each case by year of birth. Complete job histories were collected and occupational asbestos and RCF exposures were assessed using job exposure matrices. The dose-response relationships for asbestos exposure were estimated from an unconditional logistic regression model in subjects exposed to asbestos only (group 1) and subjects exposed to both asbestos and RCF (group 2). A total of 988 cases and 1125 controls ever-exposed to asbestos were included. A dose-response relationship was observed in both groups but it was stronger in group 2. In comparison with subjects exposed at the minimum value of the cumulative index of exposure, the odds ratio was 2.6 (95% CI 1.9-3.4) for subjects exposed to 75 fibres · mL(-1) · year(-1) in group 1 increasing to 12.4 (95% CI 4.6-33.7) in group 2. Our results suggest that the pleural carcinogenic effect of occupational asbestos exposure may be modified by additional exposure to RCF.

Background The association between pleural plaques and pleural mesothelioma remains controversial. The present study was designed to examine the association between pleural plaques on computed tomography (CT) scan and the risk of pleural mesothelioma in a follow-up study of asbestos-exposed workers. Methods Retired or unemployed workers previously occupationally exposed to asbestos were invited to participate in a screening program for asbestos-related diseases, including CT scan, organized between October 2003 and December 2005 in four regions in France. Randomized, independent, double reading of CT scans by a panel of seven chest radiologists focused on benign asbestos-related abnormalities. A 7-year follow-up study was conducted in the 5287 male subjects for whom chest CT scan was available. Annual determination of the number of subjects eligible for free medical care because of pleural mesothelioma was carried out. Diagnosis certification was obtained from the French mesothelioma panel of pathologists. Survival regression based on the Cox model was used to estimate the risk of pleural mesothelioma associated with pleural plaques, with age as the main time variable and time-varying exposure variables, namely duration of exposure, time since first exposure, and cumulative exposure index to asbestos. All statistical tests were two-sided. Results A total of 17 incident cases of pleural mesothelioma were diagnosed. A statistically significant association was observed between mesothelioma and pleural plaques (unadjusted hazard ratio (HR) = 8.9, 95% confidence interval [CI] = 3.0 to 26.5; adjusted HR = 6.8, 95% CI = 2.2 to 21.4 after adjustment for time since first exposure and cumulative exposure index to asbestos). Conclusion The presence of pleural plaques may be an independent risk factor for pleural mesothelioma.

Objectifs Les etudes experimentales ou epidemiologiques realisees sur les expositions aux nanoparticules ou sur la pollution particulaire ultrafine indiquent que ces expositions peuvent induire des effets deleteres sur la sante. Notre objectif est de synthetiser les donnees sur la biodistribution des nanoparticules inhalees et sur les methodes utilisees dans les etudes toxicologiques qui pourraient etre utilisees dans la surveillance des travailleurs exposes a ce type de particules. Methode Revue de la litterature portant sur les etudes de toxicocinetiques des nanoparticules et sur les case reports lies a des expositions professionnelles ou environnementales a ces particules. Resultats Les etudes toxicokinetiques suggerent que les nanoparticules sont preferentiellement absorbees par les voies respiratoires et orales avec une translocation systemique possible pouvant conduire a une accumulation dans les tissus peripheriques ou une excretion fecale et/ou urinaire. Certaines methodes utilisees dans ces etudes pourraient etre utilisees dans l’evaluation retrospective des expositions lors de la recherche d’une origine professionnelle ou environnementale d’une maladie ou dans le suivi des expositions professionnelles. Les premiers case reports publies soulignent l’importance de developper rapidement des methodes standardisees de preparation et d’analyse des echantillons afin de pouvoir caracteriser et quantifier les nanoparticules dans les echantillons biologiques. Conclusion La biometrologie des nanoparticules devrait associer des methodes d’imagerie (ex.: microscopie electronique) indispensables pour confirmer leur presence et les caracteriser dans les tissus a des methodes analytiques (ex.: ICP/MS) permettant de les quantifier et d’etablir des valeurs limites.

Although asbestos is a well-known lung carcinogen, the pleural plaque-lung cancer link remains controversial.This study was designed to examine this link in asbestos-exposed workers.A 6-year follow-up was conducted to study lung cancer mortality in the 5,402 male subjects participating in an asbestos-related disease screening program conducted from October 2003 to December 2005 in four French regions. Chest computed tomography (CT) scan was performed in all subjects with randomized, independent, double reading of CT scans focusing on benign asbestos-related abnormalities. Cox model survival regression analysis was used to model lung cancer mortality according to the presence of pleural plaques, with age as the main time variable, adjusting for smoking and asbestos cumulative exposure index. All statistical tests were two-sided.Thirty-six deaths from lung cancer were recorded. Lung cancer mortality was significantly associated with pleural plaques in the follow-up study in terms of both the unadjusted hazard ratio of 2.91 (95% confidence interval = 1.49-5.70) and the adjusted hazard ratio of 2.41 (95% confidence interval = 1.21-4.85) after adjustment for smoking and asbestos cumulative exposure index.Pleural plaques may be an independent risk factor for lung cancer death in asbestos-exposed workers and could be used as an additional criterion in the definition of high-risk populations eligible for CT screening.

Background More than 80% of mesothelioma cases in men are attributable to occupational asbestos exposure compared to only 40% in women. The objective of the study was to characterize a series of female pleural mesotheliomas according to known and suspected risk factors. Methods From the exhaustive recording of 318 female mesothelioma cases in the French National Mesothelioma Surveillance Program between 1998 and 2009, multiple correspondence analysis and hybrid clustering were performed to characterize these cases according to expert assessed occupational and non-occupational exposure to asbestos and man-made vitreous fibers, X-ray exposure, and history of cancer and non-malignant respiratory diseases. Results Four clusters were identified: (1) occupational exposure to asbestos and man-made vitreous fibers (7.9% of subjects); (2) radiation exposure during radiotherapy (12.9%); (3) increased asbestos exposure (19.8%); and (4) “non-exposure” characteristics (59.4%). Conclusion These results will allow hypotheses to be generated about associations between mesothelioma and non-occupational asbestos exposure, X-ray exposure and history of respiratory disease. Am. J. Ind. Med. 56:1307–1316, 2013. © 2013 Wiley Periodicals, Inc.

More than 80% of mesothelioma cases in men are attributable to occupational asbestos exposure compared to only 40% in women. The objective of the study was to characterize a series of female pleural mesotheliomas according to known and suspected risk factors.From the exhaustive recording of 318 female mesothelioma cases in the French National Mesothelioma Surveillance Program between 1998 and 2009, multiple correspondence analysis and hybrid clustering were performed to characterize these cases according to expert assessed occupational and non-occupational exposure to asbestos and man-made vitreous fibers, X-ray exposure, and history of cancer and non-malignant respiratory diseases.Four clusters were identified: (1) occupational exposure to asbestos and man-made vitreous fibers (7.9% of subjects); (2) radiation exposure during radiotherapy (12.9%); (3) increased asbestos exposure (19.8%); and (4) "non-exposure" characteristics (59.4%).These results will allow hypotheses to be generated about associations between mesothelioma and non-occupational asbestos exposure, X-ray exposure and history of respiratory disease.

International audience; OBJECTIVES: Whereas accumulating evidence indicates close associations between rhinitis and asthma, little is known about the relationships between occupational rhinitis (OR) and occupational asthma (OA). This study analyses the prevalence of OR associated with OA, globally and according to the various causal agents, and investigates the temporal relationships between these two conditions. METHODS: Data on incident cases of OA (2008-2010) were collected through the French national occupational disease surveillance and prevention network, using a standardised form including information on occupation, causal agents, presence of OR, and respective dates of occurrence of rhinitis and asthma. RESULTS: Among the 596 reported OA cases with latency period, 555 could be attributed to identified agents: high molecular weight (HMW) agents (n=174); low molecular weight (LMW) agents (n=381). Overall, OR was associated with OA in 324 (58.4%) cases. The frequency of association was significantly higher for HMW agents than for LMW agents (72.2% vs 51.5%, p