Peculiarities of influence of welding aerosols on the respiratory system

Abstract

Introduction. Respiratory diseases of electric welders are a common occupational disease. The cause of these diseases is associated with the effects of welding aerosols on the respiratory system. One of the important properties of aerosols, on which depends the peculiarity of their effect on the respiratory system, is their dispersion. Therefore, the study of the dispersed composition of welding aerosols entering the respiratory system is an important point for understanding the peculiarities of the formation of pneumoconiosis. Purpose of research. To investigate the aerodynamic features of welding aerosols and their permeability to the respiratory system. Materials and methods of research. The particle size of welded aerosols was studied by means of optical and electron microscopy. Sampling from the air of the working area was carried out with the patented «Method of determining dust air pollution in the premises». Sampling of inhaled and exhaled aerosol was performed with the device for determining the absorbed dose of aerosol. Results. Dust particles of different sizes both in quantitative terms and by weight are distributed on separate sites of respiratory organs as follows. Fractions up to 0.5 μm in size are mostly represented in the alveoli, fractions from 0.5 to 8.6 μm in size are mostly delayed in the larynx, trachea, bronchi, and particles larger than 8.6 μm are found in the mouth cavity and nasopharynx. Aerosol fractions with a sedimentation radius (Rs) of 10.4-12.3 μm make up the largest part of the total mass of dust deposited in the oral cavity and pharynx, fractions with Rs of 4.6-6.5 μm -in the larynx, trachea, bronchi, and fractions with Rs 0.3-0.6 μm -in the alveoli. Conclusions. Under conditions of use in the production of air recirculation system, the total weight concentrations of the welding aerosol do not reflect the actual effect of dust on the respiratory system. It would be more correct under these conditions to evaluate the effect of the aerosol on the respiratory system by the size of its respirable fraction.