Occupational Medicine in the time of COVID-19.

Editorial.

Smart working and tele-conferences during the lockdown caused by COVID-19 bring new editorial guidelines.

At the time of writing, the COVID-19 pandemic is assuming a distinct shape as do healthcare systems around the world. Some countries resisted to the tsunami and are now re-opening their industrial and commercial activities while re-organizing to face a possible new wave. Others are still struggling not to be overwhelmed by the most significant public health challenge of the last century. In Italy, after a strict lockdown, almost all activities are re-opening, trying to navigate between Scylla (epidemics and its economic consequences) and Cariddi (economic recession and its adverse health effects) bearing in mind that there is collinearity between the circulation of money and spreading of the virus and that there is a serious risk of a vicious spiral which could affect the society. The prolonged lockdown deemed to prevent the spreading of the virus also reduced the circulation of money, and hence tax revenues, thus it will ultimately result in fewer finances available for social security and Public Health (3). The main political issue will then be the definition of a right point of equilibrium between risks and benefits, between action and precaution. As scientists, we are called to distinguish between what we know and what is unknown, between data and opinions, between facts and beliefs. [...].

Subchronic exposure to titanium dioxide nanoparticles modifies cardiac structure and performance in spontaneously hypertensive rats.

BACKGROUND: Non-communicable diseases, intended as the results of a combination of inherited, environmental and biological factors, kill 40 million people each year, equivalent to roughly 70% of all premature deaths globally. The possibility that manufactured nanoparticles (NPs) may affect cardiac performance, has led to recognize NPs-exposure not only as a major Public Health concern, but also as an occupational hazard. In volunteers, NPs-exposure is problematic to quantify. We recently found that inhaled titanium dioxide NPs, one of the most produced engineered nanomaterials, acutely increased cardiac excitability and promoted arrhythmogenesis in normotensive rats by a direct interaction with cardiac cells. We hypothesized that such scenario can be exacerbated by latent cardiovascular disorders such as hypertension. RESULTS: We monitored cardiac electromechanical performance in spontaneously hypertensive rats (SHRs) exposed to titanium dioxide NPs for 6 weeks using a combination of cardiac functional measurements associated with toxicological, immunological, physical and genetic assays. Longitudinal radio-telemetry ECG recordings and multiple-lead epicardial potential mapping revealed that atrial activation times significantly increased as well as proneness to arrhythmia. At the third week of nanoparticles administration, the lung and cardiac tissue encountered a maladaptive irreversible structural remodelling starting with increased pro-inflammatory cytokines levels and lipid peroxidation, resulting in upregulation of the main pro-fibrotic cardiac genes. At the end of the exposure, the majority of spontaneous arrhythmic events terminated, while cardiac hemodynamic deteriorated and a significant accumulation of fibrotic tissue occurred as compared to control untreated SHRs. Titanium dioxide nanoparticles were quantified in the heart tissue although without definite accumulation as revealed by particle-induced X-ray emission and ultrastructural analysis. CONCLUSIONS: The co-morbidity of hypertension and inhaled nanoparticles induces irreversible hemodynamic impairment associated with cardiac structural damage potentially leading to heart failure. The time-dependence of exposure indicates a non-return point that needs to be taken into account in hypertensive subjects daily exposed to nanoparticles.

Non-invasive techniques to assess restrictive lung disease in workers exposed to free crystalline silica.

OBJECTIVES: To compare the reliability of spirometry and body plethysmography in detecting restrictive lung disease in clay excavation workers exposed to free crystalline silica (FCS). The exhaled breath condensate (EBC) biomarkers of oxidative stress were also assessed in order to evaluate early lung damage. METHODS: The study involved 62 workers (58 males and 4 females) at a company that extracts and processes clay. RESULTS: Body plethysmography (total lung capacity below the lower normal limit) and spirometry respectively indicated restrictive pattern prevalence rates of 22.6% and 1.6%. EBC 4-hydroxynonenale levels were not sufficiently sensitive to highlight a restrictive deficit, but did distinguish low and high rates of occupational exposure. There was no correlation between plethysmography values and the intensity or duration of exposure. CONCLUSIONS: Only one out of 14 cases of restrictive deficit diagnosed on the basis of body plethysmography values was also identified by means of spirometry. This finding supports the need to use body plethysmography in the health surveillance of clay workers exposed to FCS.