Organic solvents pathology

After the determination of organ weights and macroscopic examinations the tissues are processed for histo-pathological evaluations. For this they are fixed in formalin or equivalent solutions, or they are frozen (important for the diagnosis of increased fat content in a tissue, e.g. in the liver, organic solvents would dissolved the fat) trimmed to small parts, put into paraffin blocks, cut with a microtome, and stained (hematoxylin-eosin, or special staining for fat and/or collagen etc.). 

The major pathologic presentation of solvent associated nephropathy is that of anti-glomerular basement membrane disease [39] but epimembraneous and subacute proliferative glomerulonephritis have also been demonstrated. In addition, Narvarte et al. [40] reported on a patient with ulcerative colitis in which chronic interstitial nephritis developed that later was attributed to long-term exposure to organic solvents. 

The complexity of the immune system renders it readily attacked by many chemicals. Such attack may result, for example, in organ damage in the thymus, bone, and lymph nodes as well as in cellular pathology in immunocompetent cells. More than 350 different compounds have been identified as immunotoxinsJ5 6 Table 25.1 contains a representative list of these. This list includes heavy metals, chlorinated and organophosphorus pesticides, aromatic hydrocarbons, polynuclear aromatic hydrocarbons, organic solvents, and many widely used chemicals. Many lipophilic and hydrophilic chemicals are immunotoxins and the immunotoxicity of these compounds is manifest via multiple mechanisms. 

The toxic effects of organic solvent compounds on the liver are dependent on the intensity and duration of exposure, route of exposure, the intrinsic toxicity of the specific compound, as well as individual susceptibility factors. There are a number of pathologic manifestations of solvent induced hepatotoxicity, including inflammation, fat accumulation in the liver (steatosis), hepatocellular necrosis and carcinogenesis. Functional disturbances in liver physiology have also been associated with solvent exposure. 

Kronevi T, Wahlberg JE, Holmberg B (1981) Skin pathology following epicutaneous exposure to seven organic solvents. Int J Tissue React 3 21-30... 

Water should not be regarded as an irritant like anionic surfactants or lipid solvents, such as acetone. Unlike these, it is not cytotoxic but exerts its pathologic effects indirectly by markedly altering the structural organization of the horny layer, releasing pre-formed products that are stored therein. With this background, we can briefly review the abnormal clinical states in which hydration is a prominent element in pathogenesis. 

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