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Background and aims Dentists are occupationally exposed to elemental mercury from placements of mercury-containing amalgam. Although many studies have been conducted on mercury intoxication, there is still widespread concern about possible ill effects of chronic low-level mercury exposure on dentists. The present study examined the effects of occupational exposure to low levels of mercury by a group of dentists. Methods In this historical cohort study, subjects consisted of 106 dentists and 94 general practitioners (referent group), from private and public clinics in Shiraz city. Subjects were requested to complete a questionnaire on demographic variables, symptoms experienced and work practices. Additionally, using standard methods, atmospheric and urinary concentrations of mercury were measured. The data were analyzed by appropriate statistical tests. In univariat analysis, Chi-Square test was used to compare the prevalence of symptoms among both groups. Independent sample t-test and Mann-Whitney’s U-test were used to compare the mean and median of quantitative data of both groups. Multivariate logistic regression analysis was used to adjust for potential confounders. Results Both groups were similar as far as most demographic and socioeconomic variables, but age and number of personal amalgam fillings, were concerned. Median of atmospheric concentration of mercury was found to be 3.35 μg/m3. Likewise, the urinary concentration of mercury in dentists was estimated to be 3.22 μg /g.creatinine. This value was significantly higher than that of the referent group. Additionally, analysis of the data revealed that subclinical symptoms of intoxication were more prevalent in dentists. Conclusion Our findings indicate that occupational exposure to mercury by dentists, even at low levels, is associated with a significant increase in the prevalence of subclinical symptoms of intoxication.

Background and Aims Ethylene oxide is used as a sterilizing agent in health care industries. The present study aimed to assess and recognize the nature of pulmonary reactions, if any, associated with occupational exposure to ethylene oxide and to investigate the prevalence of dermal, visual, neurologic, reproductive, hematologic, hepatic and renal disorders . Methods Forty exposed and 47 unexposed employees were evaluated . Subjects were interviewed and standard respiratory symptom questionnaire as well as a questionnaire pertaining to symptoms of intoxication with this chemical were administered to them. Furthermore, parameters of pulmonary function were measured during exposure and a few days after exposure ceased Additionally, blood samples were taken for CBC, liver and kidney function tests . Moreover, atmospheric concentrations of ethylene oxide were determined by gas detector tubes . Results Respiratory symptoms such as cough and phlegm as well as dermal, visual and neurologic symptoms in exposed workers were significantly more prevalent P≤0.05 . Furthermore, significant decrements in some parameters of pulmonary function during exposure as compared with the values measured after exposure ceased, were noted . Results of biochemical tests were similar in both groups. Mean atmospheric concentration of ethylene oxide was evaluated to be 1.24±1.5 ppm. Conclusion The findings of this study indicate that exposure to ethylene oxide even at low concentrations is associated with significant decreases in pulmonary parameters. However, this effect is acute, temporary and reversible. Conversely, exposure to ethylene oxide was not associated with hematotoxic, hepatotoxic and nephrotoxic response, although, dermal, visual and neurologic symptoms were observed.

This study was carried out to assess possible toxic response(s) associated with occupational exposure to ethylene oxide (EO) in a local plant, producing disposable syringes, where the chemical was used as a sterilant. A total of 40 exposed and 47 unexposed employees were interviewed and standard respiratory symptom questionnaire as well as a questionnaire pertaining to symptoms of intoxication with EO was administered to them. Furthermore, atmospheric concentration of EO was measured by grab sampling using gas detector tubes. Additionally, parameters of pulmonary function were measured and blood chemistry test was performed. Average atmospheric concentration of EO was calculated to be 2.2 mgm−3 (1.24 ppm). Respiratory, dermal, visual, and neurologic symptoms in exposed workers were significantly more prevalent and reversible decrements were noted in some parameters of their pulmonary function. Conversely, results of biochemical tests were similar in both groups. Our findings indicate that exposure to EO results in significant decreases in some parameters of pulmonary function. However, this effect is acute, temporary, and reversible. Additionally, hematotoxic, hepatotoxic, and nephrotoxic outcomes were not evident, although, dermal, visual, and neurologic symptoms were observed. [ABSTRACT FROM AUTHOR]

Background and aim: Dentists are occupationally exposed to elemental mercury from placements of mercury-containing amalgam. Although many studies have been conducted on mercury intoxication, there is still widespread concern about possible ill effects of chronic low-level mercury exposure on dentists. The present study examined the effects of occupational exposure to low levels of mercury by a group of dentists. Method: In this historical cohort study, subjects consisted of 106 dentists and 94 general practitioners (referent group), from private and public clinics in Shiraz city. Subjects were requested to complete a questionnaire on demographic variables, symptoms experienced and work practices. Additionally, using standard methods, atmospheric and urinary concentrations of mercury were measured. The data were analyzed by appropriate statistical tests. In univariate analysis, Chi-Square test was used to compare the prevalence of symptoms among both groups. Independent sample t-test and Mann-Whitney's U-test were used to compare the mean and median of quantitative data of both groups. Multivariate logistic regression analysis was used to adjust for potential confounders. Results: Both groups were similar as far as most demographic and socioeconomic variables, but age and number of personal amalgam fillings, were concerned. Median of atmospheric concentration of mercury was found to be 3.35 μg/m³. Likewise, the urinary concentration of mercury in dentists was estimated to be 3.22 μg /g.creatinine. This value was significantly higher than that of the referent group. Additionally, analysis of the data revealed that subclinical symptoms of intoxication were more prevalent in dentists. Conclusions: Our findings indicate that occupational exposure to mercury by dentists, even at low levels, is associated with a significant increase in the prevalence of subclinical symptoms of intoxication. [ABSTRACT FROM AUTHOR]

The article discusses the risk of toxicity in the dentists exposed to low levels of mercury. According to the authors questionnaires were used to collect data relating demography and work practices from the dentists across Shiraz, Iran and concentration of mercury was measured by Atomic Absorption Spectroscopy technique. According to the results risk level is high for the dentists in the mercury exposed working area.