Humoral immune system alterations in silica exposed workers

Crystalline silica may act as an immune adjuvant to increase inflammation and antibody production. The highest exposures to silica are known to occur in the dusty trades industries such as stone- cutting. We undertook this population based study to examine the association between occupational silica exposure and humoral immune system. In this historical cohort study, 47 workers from 10 stone-cutting factories in Rey City, south of Tehran, Iran that had more than 10 years exposure to silica were included in case group and 45 individual without any exposure to silica were selected for control group. We measured serum immunoglobulins [IgM, IgG, and IgA] of participants with ELISA method and compared the results between exposed workers and control groups. The mean concentrations of two immunoglobulines [IgG, IgA] and IgM in case group in comparison with control group were higher and lower respectively but both were in normal range. IgA concentration between two groups was statistically significant [P< 0.05]. Crystalline silica exposure may promote the humoral immune system in some individuals. Additional research is recommended in other population, using study design that minimize potential selection bias and maximize the quality of exposure assessment

An unusual form of silicosis in a stone-cutter

Silicon dioxide or silica is the earth's most abundant mineral. The primary pulmonary illness attributable to silica exposure is silicosis, which is observed in three forms: classic, accelerated and acute. A case of silicosis is presented in this article who has been working in a stone-cutting plant. He had suffered from symptoms of silicosis one year after employment in this plant [acute form], but his radiologic findings were compatible with accelerated or chronic silicosis. One of the important occupational diseases is silicosis, which is not treatable but is preventable. However, because of lack of appropriate engineering controls or personal protective devices in some workplaces we observe cases of silicosis yet

[Anesthetic gases and spontaneous abortion: a historical cohort study]

There are different opinions about the relationship between spontaneous abortion and women's occupational exposure to anesthetic gases. This study and other similar studies about women's occupational exposure seems necessary as more than 50 percent of women experience pregnancy during their working life. The aim of our study was to determine the association between rate of spontaneous abortion and maternal occupational exposure to anesthetic gases. Our study was a historical cohort. Two groups of married women were studied: exposed group [women who worked in operating rooms] and unexposed group [women who worked in emergency department, ICU or CCU]. Data was collected through questionnaire and interview, and exclusion and inclusion criteria were applied. Pregnant personnel were followed till the end of 20[th] week of pregnancy. Data was analyzed using SPSS 11.5 software with frequency distribution tables, cross-tabulation tables, chisquared test, and t-test, and p<0.05 was set as significance. Findings: Spontaneous abortion rate in the exposed group was 15.7% and in the unexposed group was 13.4%. Chi-squared test showed no significant difference [p=0.529]. Odds ratio was 1.196 with a confidence interval of 0.685-2.090. Our study did not find a significant relationship between spontaneous abortion and occupational exposure to anesthetic gases, but avoidance of unreasonable exposure is rational using scavenging systems

[Alterations of hepatic enzymes in industrial painters exposed to organic solvents in Tehran]

Organic solvents are widely used in different industries and occupations. They have a central role in production and use of paints. This study was carried out to evaluate the hepatic damage due to solvent exposure. In this cross-sectional study 62 painters were selected as cases with at least one year exposure to solvents and 54 employees as controls with no exposure. Demographic and clinical information collected via questionnaire and physical examination and the results of liver function tests, [ALT, AST, ALP], were compared in the two groups. The mean levels of ALT, AST, and ALP were not significantly different between cases and controls; however the mean levels of ALT and AST in individuals with high exposure were significantly more elevated than in persons with low exposures, [subgroups of cases]. We concluded that routine hepatic enzyme tests are not suitable for early detection of hepatic damage in workers exposed to solvents and the use of more sensitive tests should be considered