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Today, cancer is one of the main health issues faced in the workplace, with asbestos an important carcinogen in the occupational environment. Among the asbestos minerals, chrysotile is the main species of socio-economic and industrial relevance. Although chrysotile asbestos is classified as a “carcinogenic substance” by the International Agency for Research on Cancer (IARC), this fiber is still mined and used in Russia. The effective health hazard posed by the Russian commercial chrysotile has not been quantitatively assessed to date. In this work, the potential toxicity/pathogenicity of Russian chrysotile was quantitatively determined using the fiber potential toxicity index (FPTI) model. This model was applied to a representative commercial chrysotile from the Orenburg region, Russia, whose morphometric, crystal-chemical, surface activity, and biodurability related parameters were determined. We have quantitatively assessed that the toxicity/pathogenicity potential of Russian chrysotile (FPTI = 2.4) is lower than that of amphibole asbestos species but higher than the threshold limit set for “safe” mineral fibers (FPTI = 2.0), although it does not contain impurities of amphibole asbestos. Differences with other chrysotile samples were discussed, and it was found that the investigated Russian commercial chrysotile shares several features with the Italian Balangero chrysotile, indicating that widespread concern on commercial Russian chrysotile is justified.

Covered by ultrabasic units for more than a third of its surface, the New Caledonia (South West Pacific) is one of the largest world producers of Ni-ore from lateritic deposits. Almost all outcrops of geological units and open mines contain serpentine and amphibole, also as asbestos varieties. In this geological context, in which weathering processes had a great contribution in the production and dispersion of mineral fibres into the environment, the development of a routinely analytical strategy, able to discriminate an asbestiform fibre from a non-harmful particle, is a pivotal requisite. However, the acquisition of all these parameters is necessary for determining the risk associated to fibres exposition. A multidisciplinary routinely approach, based on the use of complementary simply-to-use but reliable analytical methods is the only possible strategy. In addition, the instrumental apparatus must be easily transportable on the field, directly on the mining site. The employment of specialized tools such as Polarized Light Microscopy associated to Dispersion Staining method (PLM/DS) and portable Raman spectroscopy for identification of environmental asbestos, are proved extremely effective in the improvement of the performance and rapidity of data acquisition and interpretation. Both PLM/DS and handheld Raman devices confirmed to be discriminant in the detection and characterization of asbestos fibres for both serpentine and amphibole. Furthermore, these techniques proved extremely effective even in the presence of strongly fibrous and altered samples. Keywords: Asbestos, Fibrous antigorite, In situ monitoring, Dispersion staining, Portable Raman, New Caledonia

IntroductionExposure to asbestos increases the risk of lung cancer and mesothelioma. Few studies quantified the premature occurrence of these diseases in asbestos-exposed workers. Focus on premature disease onset (rate advancement or acceleration) can be useful in risk communication and for the evaluation of exposure impact. We estimated rate advancement for total mortality, lung cancer and pleural mesothelioma deaths, by classes of cumulative asbestos exposure in a pooled cohort of asbestos cement (AC) workers in Italy.MethodThe cohort study included 12 578 workers from 21 cohorts, with 6626 deaths in total, 858 deaths from lung cancer and 394 from pleural malignant neoplasm (MN). Rate advancement was estimated by fitting a competitive mortality Weibull model to the hazard of death over time since first exposure (TSFE).ResultAcceleration time (AT) was estimated at different TSFE values. The highest level of cumulative exposure compared with the lowest, for pleural MN AT was 16.9 (95% CI 14.9 to 19.2) and 33.8 (95% CI 29.8 to 38.4) years at TSFE of 20 and 40 years, respectively. For lung cancer, it was 13.3 (95% CI 12.0 to 14.7) and 26.6 (95% CI 23.9 to 29.4) years, respectively. As for total mortality, AT was 3.35 (95% CI 2.98 to 3.71) years at 20 years TSFE, and 6.70 (95% CI 5.95 to 7.41) at 40 years TSFE.ConclusionThe current study observed marked rate advancement after asbestos exposure for lung cancer and pleural mesothelioma, as well as for total mortality.

The SIML Position Paper dedicated to asbestos (PPA) is addressed (mainly) to competent practitioners (CP) for the purposes to provide a guidance about a set of items classified as markedly interesting: the actuality of asbestos exposure and the evaluation of the related risk; the diagnosis of the asbestos related diseases; the shape of the risk functions (namely about mesotheliomas); the causal relationship between exposure and disease; the medical surveillance of the workers currently and previously exposed. The scientific literature doesn't acknowledge the idea that nowadays in Italy the frequency of pleural mesotheliomas deriving from environmental asbestos from outdoor sources exposures is really a relevant item. Inside the SIML PPA the chapter concerning industrial hygiene and environmental monitoring themes shows inaccuracies and deficiencies, so resulting of scarce utility for the CPs that should be called for a more cooperative role in front of the employers. The arguments of the diagnosis of the asbestos related diseases is developed with an undue emphasis upon the differential histological diagnosis of asbestosis and, especially, of pleural mesothelioma: nosographic aspects that hardly are posed to the attention of the CP. A similar emphasis is posed towards the shape of the risk function for pleural mesothelioma, a theme absent from the current practice of the CP such as of other occupational practitioners. In conclusion, next to themes of undoubted interest for the PC, the SIML PPA dwells on the scrutiny of some topics representing critical elements of the current contrast between consultants and valuers in the context of criminal prosecutions: subjects having forensic relevance but far from the "application actuality" for the CP invoked in the PPA. A greater transparency, last but not least, was to have been posed, inside the SIML PPA, in the disclosure of the conflict of interests (COIs) of some Authors, declaring their consultancy in favour of companies.

This work describes the nature of the potentially hazardous fibrous amphibole found in the Orani’s feldspar mine (Sardinia, Italy). To identify its nature, a protocol of analysis including morphometric, chemical and crystallographic characterizations was applied. Thanks to this approach, it was possible to classify the observed fibres as tremolite after comparing chemical data, SEM/TEM observations, FTIR/ Raman spectra and X-ray diffraction data with those reported for a standard sample. The unit cell parameters of the investigated tremolite phase are a = 9.82(1) A, b = 18.08(3) A, c = 5.27(1) A, and the angle β corresponds to 104.4(1)°. The mean concentration of asbestos tremolite in the Orani’s feldspar is 0.28 wt%. Most of the fibres (0.26 wt%) are respirable ‘regulated’ fibres, representing a potential hazard. Because the total amount of tremolite in the sample is 0.6 wt%, a large fraction of it has a crystal habit other than fibrous-asbestiform or acicular. The obtained results allowed us to suggest possible solutions for a safe exploitation and mineral processing of the Orani’s mine. The procedure proposed herein may be a general tool suitable to identify the mineralogical nature of fibrous minerals in raw materials and assess if they may represent a potential health/environmental hazard.

Objective Asbestos is a known human carcinogen, with evidence for malignant mesothelioma (MM), cancers of lung, ovary, larynx and possibly other organs. MM rates are predicted to increase with a power of time since first exposure (TSFE), but the possible long-term attenuation of the trend is debated. The asbestos ban enforced in Italy in 1992 gives an opportunity to measure long-term cancer risk in formerly exposed workers. Methods Pool of 43 previously studied Italian asbestos cohorts (asbestos cement, rolling stock, shipbuilding), with mortality follow-up updated to 2010. SMRs were computed for the 1970–2010 period, for the major causes, with consideration of duration and TSFE, using reference rates by age, sex, region and calendar period. Results The study included 51 801 subjects (5741 women): 55.9% alive, 42.6% died (cause known for 95%) and 1.5% lost to follow-up. Mortality was significantly increased for all deaths (SMR: men: 1.05, 95% CI 1.03 to 1.06; women: 1.17, 95% CI to 1.12 to 1.22), all malignancies combined (SMR: men: 1.17, 95% CI to 1.14 to 1.20; women: 1.33, 95% CI 1.24 to 1.43), pleural and peritoneal malignancies (SMR: men: 13.28 and 4.77, 95% CI 12.24 to 14.37 and 4.00 to 5.64; women: 28.44 and 6.75, 95% CI 23.83 to 33.69 and 4.70 to 9.39), lung (SMR: men: 1.26, 95% CI 1.21 to 1.31; women: 1.43, 95% CI 1.13 to 1.78) and ovarian cancer (SMR=1.38, 95% CI 1.00 to 1.87) and asbestosis (SMR: men: 300.7, 95% CI 270.7 to 333.2; women: 389.6, 95% CI 290.1 to 512.3). Pleural cancer rate increased during the first 40 years of TSFE and reached a plateau after. Discussion The study confirmed the increased risk for cancer of the lung, ovary, pleura and peritoneum but not of the larynx and the digestive tract. Pleural cancer mortality reached a plateau at long TSFE, coherently with recent reports.

For the first time, this work reports concentration maps of asbestos minerals in contaminated mine tailings drawn using the results of Rietveld quantitative phase analysis (QPA). The investigated sites are located in the Valle d’Aosta region (Italy): Cretaz, the most important Italian magnetite mine, active until 1979 and Emarese, one the most important chrysotile asbestos mines in Italy, active until 1968. The results of the study permit to draw the spatial distribution of the asbestos (chrysotile and tremolite in this specific case) concentration, useful to plan reclamation of the sites, with priority given to the areas with the highest asbestos concentration. Because of the complexity of the mineral assemblage, which includes, among the others, antigorite, chlorite, talc, and tremolite, the concentration of chrysotile was cross-checked using different experimental techniques such as X-ray powder diffraction (XRPD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), polarized light optical microscopy (PCOM), and differential thermal analysis (DTA). The accuracy of the results was validated by analyzing standard samples with known concentrations of chrysotile and tremolite. The comparison allowed to point out the advantages and disadvantages of each experimental method. At Cretaz, chrysotile ranges from 4.4 to 22.8 wt% and tremolite from 1.0 to 10.3 wt%, whereas at Emarese the concentration of chrysotile varies from 3.3 to 39.5 wt% and tremolite from 5.9 to 12.4 wt%. Antigorite and chlorite are the major accompanying phases with variable amounts of other accessory minerals including magnetite, carbonates, talc, olivine, pyroxene, talc, and brucite. The results of our study are of key importance for the local environmental policies as the knowledge of the spatial distribution of the asbestos concentration allows to plan a detailed reclamation agenda of the contaminated sites. The spots with the highest surface contamination of both chrysotile and tremolite were identified and classified as priority areas in the reclamation plan.

One of the open questions regarding the asbestos problem is the fate of the mineral fibres in the body once inhaled and deposited in the deep respiratory system. In this context, the present paper reports the results of an electron microscopy study of both mineral fibres and asbestos bodies found in the lung tissue of a patient who died of malignant mesothelioma due to past occupational exposure. In concert with previous in vivo animal studies, our data provide evidence that amphibole asbestos fibres are durable in the lungs, whereas chrysotile fibres are transformed into a silica‐rich product, which can be easily cleared. Amphibole fibres recovered from samples of tissue of the deceased display a high degree of crystallinity but also show a very thin amorphous layer on their surface, 31% of the fibres are coated with asbestos bodies consisting of a mixture of ferroproteins (mainly ferritin). Here, we propose an improved model for the coating process. Formation of a coating on the fibres is a defence mechanism against fibres that are longer than 10 &micro, m and thinner than 0.5 &micro, m, which macrophages cannot engulf. The mature asbestos bodies show signs of degradation, and the iron stored in ferritin may be released and potentially increase oxidative stress in the lung tissue.

Objective Asbestos causes mesothelioma (MM) and cancer of lung, ovary, larynx and possibly other organs. Risk reduction after cessation of exposure and at long latency is debated. For MM, the predicted increase of rates with time since first exposure (TSFE) might be attenuated by fibre clearance. The ban of asbestos use in Italy gives an opportunity to measure long term risk in formerly exposed workers. Methods In a pool of 43 Italian asbestos cohorts (asbestos-cement, rolling stock, shipbuilding and other industries), standardised mortality ratios (SMRs) were computed for the major causes, with consideration of time factors (period, duration, latency). The functional relation between pleural cancer mortality rates and TSFE was evaluated using Poisson regression, including a term for fibre clearance. Results The study includes 54,409 subjects (6,054 women): 55.3% alive, 43.0% died (cause known for 94%; 789 pleural cancers), and 1.7% lost to follow-up. Mortality was increased for all causes (SMR = 1.06; p Discussion Our results provide information on the risk after asbestos exposure, even for rarer diseases. Increased risk for ovarian cancer is confirmed. Results agree with the hypothesis that pleural cancer risk, rather than increasing indefinitely, reaches a plateau at long latency, coherently with asbestos clearance from the lungs. As a consequence, early exposures to asbestos cannot be considered to be the exclusive determinant of the long term development of pleural cancer, with implications also for the risk related to non occupational exposure and for asbestos removal.

Objective. Asbestos causes mesothelioma (MM) and cancer of lung, ovary, larynx and possibly other organs. Risk reduction after cessation of exposure is debated. For MM, the predicted increase of ra...

This study aims at investigating, in asbestos exposed workers, the time trend of their risk of mesothelioma and of other neoplasm after very long latency and after the cessation of asbestos exposure. We pooled a large number of Italian cohorts of asbestos workers and updated mortality follow-up. The pool of data for statistical analyses includes 51,988 workers, of which 6,058 women: 54.2% was alive at follow-up, 42.6% was dead, and 2.8%was lost. Cause of death is known for 94.3%: 2,548 deaths from lung cancer, 748 frompleural cancer, 173 fromperitoneal cancer, and 434 from asbestosis. An exposure index is being developed to compare the different cohorts. Data analysis is in progress. This study will have the size for analysing not only time trends in mesothelioma, but also the occurrence of rarer diseases and cancer specific mortality in women.

Feed mill workers may handle or process maize contaminated with aflatoxins (AFs). This condition may lead to an unacceptable intake of toxins deriving from occupational exposure. This study assessed the serological and urinary levels of AFs in workers exposed to potentially contaminated dusts in two mills. From March to April 2014, blood and urine samples were collected, on Monday and Friday morning of the same working week from 29 exposed workers and 30 non-exposed controls. AFs (M1, G2, G1, B1, B2) and aflatoxicol (AFOH) A were analyzed. Each subject filled in a questionnaire to evaluate potential food-borne exposures to mycotoxins. AFs contamination in environmental dust was measured in both plants. No serum sample was found to be positive. Seventy four percent of urine samples (73.7%) revealed AFM1 presence. AFM1 mean concentration was 0.035 and 0.027 ng/mL in exposed and non-exposed workers, respectively (p = 0.432); the concentration was slightly higher in Friday’s than in Monday’s samples, in exposed workers, 0.040 versus (vs.) 0.031 and non-exposed controls (0.030 vs. 0.024, p = 0.437). Environmental AFs contamination ranged from 7.2 to 125.4 µg/kg. The findings of this study reveal the presence of higher AFs concentration in exposed workers than in non-exposed controls, although these differences are to be considered consistent with random fluctuations.