doi
Kiev Research Institute of Occupational Hygiene and Occupational Diseases
The biological activity of metal compounds included in welding aerosols (SA) depends on their ability to bind with proteins of blood and tissues, increase the permeability of cell membranes or damage them, block many intra- and extracellular enzyme systems, which ultimately leads to the development of pathological changes in organism. Currently, it is customary to distinguish two universal mechanisms of cell damage: irreversible covalent binding of harmful substances to biomacromolecules and oxidative stress, ie, lipid peroxidation, accompanied by the activation of lipid peroxidation (LPO) [1, 3]. In the latter case, the leading factors in the disorganization of cell metabolism are the degradation of structural lipoproteins of cell membranes, inactivation of enzymes built into the membrane, uncoupling of oxidative phosphorylation in mitochondria, activation of lysosomal enzymes, and accumulation of inert polymers - products of crosslinking and polymerization, dependent on the activation of LPO process [5]. In this regard, in the pathogenesis of intoxication at the cell level, the loss of the specificity of the damaging effect is possible, and organ specificity can be largely determined only by differences in the number of affected cells, which together leads to disorders in the structure and function of the organ [3].
It was determined that, based on the totality of the revealed changes, all studied CAs had a significant damaging effect on the lungs, liver and blood of experimental animals. On the 30th day of the experiment, these shifts increased, which manifested itself in lung homogenates by a significant decrease in resistance to LPO, a pronounced accumulation of MDA and an increase in the rate of its formation; in liver homogenates - damage to biological membranes of hepatocytes, increased production of LPO products and increased intake of cytoplasmic and lysosomal enzymes into the blood. In this case, the amount of enzymes entering the blood was determined by the degree of membrane disruption, while their spectrum (cytoplasmic, lysosomal enzymes) depended on the strength of the damaging effect. Therefore, it can be argued that the studied CAs have membranotoxic effects.
In general, the studies carried out made it possible to establish a high informativeness of using indicators of the functional state of the SRO system as a criterion for assessing the biological effect of SA, the change in which was mainly in direct correspondence with changes in other indicators of hazardousness of SA. This also indicates that the concept of "nonspecificity" of toxicity is promising in particular toxicological studies, confirms the criterion significance of primary disorders of cellular and tissue homeostasis in assessing the biological effect of CA.