Respiratory health disorders among workers in some Egyptian welding enterprises.

Welding fumes contain a complex mixture of metallic oxides that pose a risk to welders' respiratory systems. This study aimed to evaluate respiratory health disorders among workers in some Egyptian welding enterprises and their relationship to the workplace environment. This research was performed from January 1st, 2019 to February 28th, 2021 in welding enterprises in Birket El-Sabaa, a randomly selected district of Menoufia governorate, Egypt. A cross-sectional comparative study was conducted on 110 welders and 110 non-occupationally exposed subjects. Environmental studies were carried out for total welding fumes, respirable dust, and manganese air levels. Spirometric measures and manganese levels in whole blood were applied. Analysis of the personal air samples revealed that the mean values of welding fumes, respirable dust, and manganese air levels were higher than the international permissible levels. Welders had a higher significant prevalence of respiratory manifestations (rhinitis, cough, expectoration, wheezes, dyspnea, and chronic bronchitis) as well as decreased spirometric measures (FVC%, FEV1%, FEV1/FVC%, and FEF25-75%) than controls. The mean value of whole blood manganese level was statistically significantly higher among welders than that of the controls (3.35 ± 0.5 and 1.81 ± 0.79 ng/mL; respectively). A significant relationship was reported between longer work time and the prevalence of respiratory manifestations and decreased spirometric measurements. The use of masks/respirators was associated with a reduced prevalence of respiratory manifestations. Finally, welders that are exposed to welding fumes at concentrations higher than the permissible levels in welding establishments suffer from adverse respiratory problems, as shown by increased prevalence of respiratory manifestations and lower spirometric measurements. Regular use of high-quality personal protective equipment, especially masks, as well as periodic medical examinations for welders, is highly urged.

Altered tumor suppressor genes expression in Egyptian pesticide applicators exposed to organophosphate insecticides.

Occupational exposure in spraying and application of non-arsenical insecticides has been classified as a probable human carcinogen. The fundamental molecular mechanisms involved the tumor-related genes. This study aimed to investigate the carcinogenesis effects related to chronic exposure to organophosphate (OP) pesticides in pesticide applicators. This was a cross-sectional study conducted on 27 pesticide applicators and 24 matched controls through the period from June to December 2018. The level of acetylcholinesterase (AChE) was determined and the effects of OPs exposure on messenger RNA (mRNA) expression of the DNA-damage responsive genes P53, P21, GADD45a, and MDM2 were determined using real-time quantitative polymerase chain reaction. A significant reduction of serum AChE enzyme activities was observed in chronically exposed subjects in comparison with the control group (p = 0.001). The expression of P53, P21 mRNA was significantly downregulated in the exposed group compared with the healthy nonexposed control group (p < 0.05). Conversely, the expression of MDM2 and GADD45a did not significantly differ between the exposed subjects and the control group (p > 0.05). No significant differences were noted between the exposed and control groups regarding the genotype or allele distributions of P53 Arg72Pro polymorphism. These results suggested that chronic exposure to OP insecticides may have mitogenic and carcinogenicity activity for the exposed cases due to downregulation of P53 and P21 but did not demonstrate any DNA damage properties for the exposed cases, and finally, a regular follow-up of the exposed cases for tumor markers is recommended.