Influence of free radicals on cardiovascular risk due to occupational exposure to mercury.

This study was designed to investigate the relation between occupational exposure to mercury and cardiovascular risk, as well as free radicals. The study subjects included 30 male workers exposed to mercury from a fluorescent lamp plant in Alexandria after exclusion of 12 workers with conditions that may bias the results. A matched control group of 20 male subjects were selected from a food industrial plant. The participants were subjected to interview, clinical examination, electrocardiography and R-R deep breathing variability test as a measure of cardiac autonomic function. Spot urine and venous blood samples were collected to measure mercury levels. Free radicals related markers were measured in serum namely lipid peroxide, superoxide dismutase (SOD) activity, catalase activity and glutathione S-transferase. Results showed significant longer electrocardiographic Q-Tc interval, which is corrected to heart rate, in exposed workers than in controls (p=0.002). The R-R deep breathing variability indices were significantly increased among exposed workers in comparison to controls (maximal variation (MV) ratio, p=0.024 & MV rate, p=0.019). The mercury levels in both urine and blood of exposed workers were significantly higher than controls (p<0.0001), with mean levels exceeding the permissible limits. Free radicals related markers revealed significant higher level of lipid peroxide, as well as significant lower levels of SOD activity, catalase activity and glutathione S-transferase among exposed workers than among controls (p<0.0001 for all). Independent relations were observed between Q-Tc and lipid peroxide, and between MV rate and SOD and catalase activities among exposed workers after adjustment for the confounders by multivariate regression analyses. These findings may suspect a cardiac autonomic dysfunction probably related to free radicals in mercury exposed workers. Also, it may through light on some preventive implications.

Study of some biological markers of stress in nail industry.

The aim of this study was to investigate the different markers of stress in nail industry. Blood and urine biological samples were collected from 30 exposed workers and 30 age and sex matched control subjects from the administrative department of the same factory. The total antioxidant activity (Dmax) and lipid peroxidation was analyzed in blood. The level of catecholamines in the urine was also determined The median level of Dmaxwas significantly lower in the exposed workers (87.12) compared with that of the control (115.85) (p < 0.01). Also the level of lipid peroxidation was significantly lower in the exposed workers (44.5) compared with that of the control (74.0) (p < 0.01). The median level of urinary catecholamines was significantly higher in the exposed workers (295) compared with that of controls (37.5). Attention should be paid to the necessity of the application of the different biological markers of stress in different sectors of industry especially in nail industry.

Respiratory enzymatic changes among workers in glue industries.

The aim of this study was to investigate the respiratory enzymatic changes among workers in glue industries. Blood and urine samples were collected from 30 exposed workers and 30 age and sex matched control subject from the administrative department of the same factory. Different respiratory enzymes were analyzed in blood. The level of urinary phenol was also determined. The median level of different respiratory enzymes (catalase, glutathione peroxidase, glutathione reductase and carbonic unhydrase) were significantly higher in the exposed workers compared to control subjects. Also the median level of urinary phenol was significantly higher in exposed workers compared with that of controls. Attention should be paid to the different occupational health hazard, existing in different types of glue industries.

Assessment of antisperm antibody in sera of mercury and lead exposed workers.

Occupational exposure to lead or mercury was found to make protein better antigens. The production of autoantibodies to nervous system protein is one example of such effect. The present study aims to detect the possibility of induction of antisperm autoantibodies due to occupational exposure to lead or mercury. Male workers exposed to lead (n = 50) or to mercury (n = 39) were selected for this purpose and compared to a matched control group (n = 39). A negative control consisting of 17 females was also included. All subjects had two or more children. Blood samples were collected and the ELISA technique was applied to detect antisperm antibodies. Also, the levels of lead in blood and mercury in urine were determined as biological indices of exposure. Antisperm antibodies were detected in 90% of workers exposed to lead with the predominance of the IgG type and 84.6% of workers exposed to mercury with the predominance of the IgM type. Although the results did not correlate with the biological indices of exposure, it seems advisable to use the detection of sperm antibodies of sera of workers exposed to metals as a biological monitoring tool.

Biological monitoring of occupational exposure to benzene and toluene.

This study was carried out to evaluate the biological monitoring of occupational exposure to benzene and toluene in a total number of 31 male exposed workers and 30 control subjects. The present study showed a statistically significant higher level of biological indices of exposure (p < 0.01) of phenol and hippuric acid in urine of workers exposed to benzene and toluene than control subjects. Significant changes (p < 0.05, 0.01) in the levels of hematological and biochemical findings have been observed among exposed workers and control group. In addition, statistically significant higher levels of Mg, Mn and Ca were found among workers exposed to benzene and toluene while statistically significant lower levels of serum iron (p < 0.05) have been observed. No significant variations could be detected in the level of Zn and Cu between exposed and control subjects.

Teratogenic effect of diphenylhydantoin and/or fluphenazine in mice.

Diphenylhydantoin and fluphenazine are two drugs that act on the central nervous system. Many patients are taking these two drugs together and sometimes during pregnancy. Therefore, this study was conducted to determine the safety or the teratogenic effect of these two drugs alone or in combination. Pregnant mice were administered diphenylhydantoin at 50 mg kg-1 body wt. and/or fluphenazine at 1 mg kg-1 body wt. by gavage. The control group was administered the vehicle of diphenylhydantoin (water containing 0.6% alcohol). All pregnant animals were treated from day 6 to day 15 of gestation. The females were sacrificed on day 18. A significant reduction of fetal weight and length was found in all treatment groups when compared to the control. As regards to skeletal anomalies, it was found that the incidence of incomplete ossification of sternebrae and skull bones was significantly increased in the combination group when compared to the control group. Examination of visceral anomalies showed that dilated cerebral ventricles were observed in the fluphenazine-treated group, with the incidence of these malformations increasing significantly when diphenylhydantoin was administered in combination with fluphenazine. In summary, the administration of diphenylhydantoin and fluphenazine in combination was shown to be more teratogenic than each drug alone.