[Occupational exposure to a mixture of organic solvents and prevalence of hypertension in workers of a car manufacturing company]

Hypertension [HTN] is a common disease with various complications for health. A number of studies suggested that some organic solvents can affect blood pressure and usually workers in work environments expose to mixtures of solvents. We decided to survey the effects of a mixture of organic solvents on blood pressure in workers of a car manufacturing company. In a cross-sectional study, systolic and diastolic blood pressure [SBP and DBP] of 179 workers of a car manufacturing plant was measured. Workers in the repair location as non-exposure group and workers in the paint location as exposure group were compared in terms of systolic and diastolic blood pressure [SBP and DBP] and prevalence of hypertension and pre-hypertension. There were no statistically significant differences between groups in the variables, age, employment duration, smoking and other confounding factors [p>0.05]. The mean values of SBP and DBP was significantly higher in exposure group than non-exposure group [p<0.001]. After logistic regression analysis with adjustment of confounding variables, prevalence of pre-hypertension and hypertension was significantly higher in exposure group than non-exposure group [p<0.05]. Further, in this study there was a significant association between hypertension and variables such as age, smoking, body mass index, regular exercise and shift work [p<0.05]. Our results suggested that, exposure to mixture of organic solvents can increase prevalence of hypertension in car manufacture workers. Therefore, more attention should be paid to such workers by prevention and periodic monitoring of blood pressure.

[Assessment of relationship between spontaneous abortion and occupational exposure to organic solvents]

Nowadays, some studies indicate the adverse effects of exposure to chemicals, especially organic solvents on the reproductive system of females. This study aimed to assess the relationship between spontaneous abortion with occupational exposure to organic solvents in pharmaceutical industry. This is a cross-sectional and descriptive-analytical study which was carried out in 2010 in one of the pharmaceutical factories located in the suburbs of Tehran. During the study, married women who were working in the factory laboratory units and were exposed to mixed organic solvents were compared with married women who were working in the packing units of the factory without occupational exposure to organic solvents. Frequency of spontaneous abortion and duration of pregnancy were assessed in both two groups. Collected data were analyzed with the SPSS software using t-test, logistic regression, and chi-square test. In the present study, the frequency of spontaneous abortion in employees with exposure to organic solvents mixture was 10.7%. This study showed that even after adjustment for confounding factors, there was a significant correlation between spontaneous abortion and occupational exposure to organic solvents mixture and this correlation increased with increasing levels of exposure to organic solvents. Moreover, a significant correlation was observed between occupational exposure to mixed organic solvents and waiting time to become pregnant [TTP]. Furthermore, this study showed that even after adjustment for confounding variables, shift workers were significantly more affected by spontaneous abortion compared to daytime workers [P<0.001]. According to the results of this study, since there is probability of spontaneous abortion resulting from occupational exposure to various chemicals including organic solvents, review of the status of occupational exposure of workers can be helpful in improving the reproductive health of female workers

[Assessment of ischemic heart diseases and related risk factors in professional drivers]

Nowadays cardiovascular disorders are the most common cause of death in worldwide. Several studies have shown that ischemic cardiovascular diseases are more common in drivers, especially professional drivers, but underlying causes have not been completely understood. This study was a cross sectional, descriptive-analytic study. 1120 professional divers who worked with heavy vehicles and referred for periodic examinations to one of the centers of drivers examinations in city of Yazd with simple random sampling included in the study. The study findings showed that age, overweight, cigarette smoking, duration of driving, chronic diseases known as a risk factor for ischemic heart disease, such as diabetes mellitus, hypertension, hyperlipidemia, had a significant relationship with ischemic heart diseases [p <0.05], and second job, family history of ischemic heart diseases risk factors, vehicle type and regular exercise had not a significant relationship with ischemic heart diseases [p>0.05]. Because of high prevalence of cardiovascular diseases and their risk factors in drivers and lack of a concentrated system for driver's education, it seems that decreasing of these risk factors requires occupational medicine examination centers educate them too

Assessment of hearing standard threshold shift based on audiometric findings in steel company workers

Exposure of workers to excessive noise and its complications including hearing loss as one of the most important health problems in industries. Standard Threshold Shift [STS] is considered as an indicator for monitoring of the effectiveness of hearing conservation program [HCP] implemented in the industries. This study was designed to determine the frequency of STS and hearing loss in steel industry workers. 310 steel workers with sound level exposure to unauthorized noise [85 dBA or higher] that had at least 3 years work experience were enrolled. Required data were recorded in a questionnaire through direct interview. STS was investigated using baseline audiogram and audiometric evaluations. 22.3% of workers in 2008 and 41.3% of workers in 2009 had STS in both ears. There was a significant relationship between the sound exposure level and work experience with STS, while the relationship between age and STS was not significant. High frequency of STS in workers indicates unsuccessful hearing conservation program in the factory and careful implementation and reassessment of HCP seem necessary

[Effects of occupational exposure with mixture of aromatic organic solvents on liver enzymes in workers of an automobile plant]

Organic solvents have a broad range of application in industry. Hepatotoxicity of different organic halogenated solvents like carbon tetrachloride has been verified in numerous studies; however, studies investigating the association between the occupational exposure with aromatic organic solvents like benzene, toluene and xylene and hepatic toxicity are limited. The goal of this study was to review the long term effects of exposure with mixture of aromatic organic solvents, in higher amounts of permissible level, on hepatic system. This is a cross sectional study which was conducted in an automobile plant. Workers employed in the painting saloon were considered as cases and workers in assembly as controls. A questionnaire, containing demographic data like age and years of employment, was completed for each of 349 workers. After considering exclusion criteria, liver enzyme level [AST, ALT and ALP] of 163 case workers was compared with 186 controls. Concentration of mixture of organic solvents in painting saloon was twice and a half as much of the permissible level. The collected data was analyzed by the SPSS software, using T score, K2 and Linear Regression. The Mean level of ALP in case group was significantly higher than the control group [P<0.001]. For AST and ALT the mean was higher in the case group but this difference was not statistically significant. Increase in ALP level had a significant association with BMI [P<0.001] and smoking [P=0.007]; yet, no significant relation was seen with age and years of employment. Our study suggested that exposure with mixture of aromatic organic solvents, in higher amounts of permissible level, can cause mild functional liver damage [cholestatic type]. So, it is recommended to use liver function tests, especially ALP, for screening of workers exposed to mixture of aromatic organic solvents, for preliminary detection of hepatic dysfunction

Effect of exposure to low levels of organic solvent mixtures On color vision

Color vision deficiency has a relatively high prevalence in working population and cause difficulties in everyday tasks. Occupational exposure to various neurotoxic chemicals has been shown to be associated with acquired color vision impairment. This study was undertaken to determine the effect of occupational exposure to mixed organic solvents at low levels on color perception. A cross sectional study was conducted in an automobile plant. Workers employed in painting saloon, were considered as cases and workers employed in assembly saloon were considered as controls, as well. We administered a questionnaire, containing age, years of employment, histories of congenital color vision impairment or eye injuries, alcohol consumption and for workers. After considering exclusion criteria, Color vision of 121 case workers compared with 157 controls. The LD-15 test showed that 31.4% of case group had an acquired color vision defect .Most defects were of the blue-yellow type in the case group. Also the prevalence of acquired color vision defect was 3.8% in the control group. The prevalence of acquired color vision defect of exposed employees were statistically significantly higher than those of the control subjects [OR = 11.52, CI = 4.67- 28.38] [P<0.001]. Besides mean of the color-confusion index [CCI] derived from the LD-15 test for exposed employees were statistically significantly higher than those of the control subjects [1.14 and 1.03 respectively and P<0.001].The logistic regression for color confusion index [CCI] showed that it was positively related to exposure to mixed organic solvents [P<0.001]. The results of this study suggest that, chronic occupational exposure to mixed organic solvents even at lower concentrations than permissible levels can cause acquired color vision impairment. Also acquired color vision impairment seems to be a sensitive indicator which can detect solvent-induced neurotoxicity in car painters. Finally we propose that the color confusion index [CCI] may be used as an appropriate indicator of early neurotoxic effects in workers exposed to low concentrations of mixture of organic solvents

[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