Mucsculoskeletal disorders among municipal solid waste workers

Waste collection is a necessary activity all around the world and the removal of municipal solid waste is a job associated with a variety of biological, chemical, mechanical, physical, and psychosocial hazards. In our country, like many developing countries, municipal solid waste is collected manually and collection of household waste is also a job which requires repeated heavy physical activity such as lifting, carrying, pulling, and pushing. We performed this study to evaluate musculoskeletal disorders among municipal solid waste workers. We designed a cross sectional study. Our survey instrument for measurement of musculoskeletal symptoms was adapted from the Standardized Nordic Questionnaire that translated into Farsi language. A total of 65% [n=142] of participants reported that they had been troubled with musculoskeletal symptoms in one or more of the 9 defined body regions during the last 12 months. Prevalence of symptoms in low back, knees, shoulders, upper back and neck were 45, 29, 24, 23 and 22% respectively. Foreign workers reported more musculoskeletal symptoms in all body parts than Iranian workers. The differences between prevalence of symptoms between two groups were significant in all parts of body except knees. The study found that solid waste workers have more musculoskeletal disorders than general population. Meanwhile these symptoms were more common among foreign workers. The risk of disease was increased with the increasing years of working as solid waste worker and smoking. We didn't find relationship between musculoskeletal disorders and education or marriage status of workers

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

[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

[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

[Surveying liver enzymes in workers exposed to vinyl chloride vapors]

Polyvinyl chloride [PVC] is used primarily to produce home appliances however, its production without vinyl chloride [VCM] is not reproducible. VCM has harmful effects on liver when is exposed during a long term duration. We surveyed long term liver effects with exposure of mild to moderate amounts of VCM. In this case-control study, liver enzymes levels of 52 workers were compared with 48 staff employees using t-test analysis. Case group was composed of all occupied workers in PVC production unit [one of the petrochemical complex], while, the control group was chosen form administrative staff of the same petrochemical complex. The mean level of alkaline phosphatase [ALP] and gamma glutamine trans peptidase [GGT] were shown to be significantly differed between the two groups. Other measures such as AST, ALT, and direct and indirect billirubin were revealed to be higher in case group, however, their difference did not reach a statistically significant level. Results revealed that exposure to even low levels of VCM may lead to mild liver cholestatic damage, therefore, use of tests for liver cholestasis such as GGT and ALP for individuals working in PVC production units should be kept in mind periodically

[Comparing helicobacter pylori infection between dentistry and pharmacy students in Tehran]

The route of person-to-person transmission of helicobacter pylori may be either fecal-oral or oral-oral, because the bacterium is found in both dental plaque and feces. We assessed the prevalence of H. pylori, which reflects present or past infection in dental students exposed occupationally to dental plaque. We examined the sera of 68 dental students and residents [24 residents and 44 students] and 69 age-matched controls by using quantitative ELISA for antibodies of lgG class to H. pylori. The proportion of dental group seropositive for H. pylori was [39 of 68] 57.4%, the proportion of control group seropositive for H. pylori was [40 of 69] 58%. There was no significant difference between groups. We conclude that dental practice in dental students does not increase the risk of H.pylori infection