Comparative characteristics of cytotoxicity of solid component of welding fumes, depending on the hexavalent chromium content

Leather made with soybean phospholipid fatliquors is prone to problems such as yellowing, elevated hexavalent chromium content, and undesirable odor. In this study, the aforementioned typical defects of soybean phospholipid fatliquors were investigated in respect to the main components, the antioxidants and the unsaturation degree of the natural soybean phospholipid. The results showed that the oxidation of soybean phospholipid is the primary source for its yellowing, elevated hexavalent chromium content, and undesirable odor. The volatile aldehydes produced by lipid oxidative rancidity are the main components of the undesirable odor. The purification of natural soybean phospholipid through removing the non-phospholipid components cannot solve the problems caused by oxidation of phospholipid. Furthermore, as a typical natural antioxidant existing in natural soybean phospholipid, tocopherols can restrain the oxidation of phospholipid to a certain degree, however, the dissolving out and destruction of tocopherols at high temperature in the phospholipid purification process can lead to more obviously oxidation of phospholipids. Additionally, the oxidation defects of phospholipid cannot be completely resolved by adding extra tocopherols, even at high dosages. The research finds that the defects of soybean phospholipid fatliquors can be thoroughly solved by increasing the saturation degree of lipid through addition reaction, the suggested iodine value of phospholipid products is lower than 20 g I2/100 g.

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Exposure to Welding Fumes, Hexavalent Chromium, or Nickel and Risk of Lung Cancer

American Journal of Epidemiology ◽

10.1093/aje/kwz187 ◽

2019 ◽

Vol 188 (11) ◽

pp. 1984-1993 ◽

Cited By ~ 6

Author(s):

Beate Pesch ◽

Benjamin Kendzia ◽

Hermann Pohlabeln ◽

Wolfgang Ahrens ◽

Heinz-Erich Wichmann ◽

...

Keyword(s):

Lung Cancer ◽

Hexavalent Chromium ◽

Regression Models ◽

Welding Process ◽

Cumulative Exposure ◽

Welding Fumes ◽

Odds Ratios ◽

Case Control Studies ◽

High Exposure ◽

Logistic Regression Models

Abstract To investigate the risk of lung cancer after exposure to welding fumes, hexavalent chromium (Cr(VI)), and nickel, we analyzed 3,418 lung cancer cases and 3,488 controls among men from 2 German case-control studies (1988–1996). We developed a welding-process exposure matrix from measurements of these agents, and this was linked with welding histories from a job-specific questionnaire to calculate cumulative exposure variables. Logistic regression models were fitted to estimate odds ratios with confidence intervals conditional on study, and they adjusted for age, smoking, and working in other at-risk occupations. Additionally, we mutually adjusted for the other exposure variables under study. Overall, 800 cases and 645 controls ever worked as regular or occasional welders. Odds ratios for lung cancer with high exposure were 1.55 (95% confidence interval (CI): 1.17, 2.05; median, 1.8 mg/m3 × years) for welding fumes, 1.85 (95% CI: 1.35, 2.54; median, 1.4 μg/m3 × years) for Cr(VI), and 1.60 (95% CI: 1.21, 2.12; median, 9 μg/m3 × years) for nickel. Risk estimates increased with increasing cumulative exposure to welding fumes and with increasing exposure duration for Cr(VI) and nickel. Our results showed that welding fumes, Cr(VI), and nickel might contribute independently to the excess lung cancer risk associated with welding. However, quantitative exposure assessment remains challenging.

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