سال:1397 | دوره: | شماره: |تعداد مقالات:7

Background: Dental staff may be at increased risk of adverse pregnancy outcome secondary to their chronic exposure to mercury.Objective: To investigate obstetric outcome among dental staff and explore the oxidative stress induced by mercury exposure.Methods: A cohort of 64 pregnant dental staff (exposed group) and 60 pregnant employees (non-exposed group) were studied. Urinary mercury level and blood antioxidant activity were measured. Participants were followed to assess their obstetric outcome.Results: The exposed group had a higher mean urinary mercury level and a lower blood antioxidant activity during the three trimesters compared to non-exposed group (p<0.001). Women in the exposed group were experienced more frequently spontaneous abortion and pre-eclampsia (p<0.05). Babies born to the women in the exposed group tended to be smaller for gestational age compared to those of non-exposed group (p<0.001).Conclusion: Pregnant dental staff suffered higher odds of developing spontaneous abortion and pre-eclampsia and giving birth to babies smaller for gestational age. This may be linked to oxidative stress induced by exposure to mercury.

Background: Cotton dust exposure among textile mill workers lead to impaired lung function. However, only few studies have investigated the dose-response relationship between cotton dust and lung function.Objective: To determine the dose-response relationship between cotton dust exposure and lung function among textile workers.Methods: This cross-sectional survey was conducted from January to March 2016 and included 303 adult male textile workers from spinning and weaving sections of 5 mills in Karachi, Pakistan. We collected data through a translated version of the American Thoracic Society respiratory questionnaire (ATS-DLD-78A) and using spirometry. Mill-level airborne cotton dust was measured over an 8–12-hour shift through UCB-PATS (University of California, Berkeley- Particle, and Temperature Monitoring System). Multiple linear regression was used to determine the association between cotton dust exposure and lung function assessed through the 3 indices: forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), and their ratio (FEV1/FVC).Results: The mean age of the workers was 32.5 (SD 10.5) years. The mean spirometry indices expressed in percent predicted values were FEV1 82.6 (SD 14.0); FVC 90.3 (14.7), and FEV1/FVC 94.9 (10.5). The median cotton dust concentration was 0.61 (IQR 0.2 to 1.3) mg/ m3. The frequency of respiratory symptoms was 15% for cough, 20% for phlegm, and 20% for wheezing. After adjustment for covariates, every mg/m3 increase in dust concentration was associated with 5.4% decline in FEV1.Conclusion: This study quantifies the exposure-dependent relationship between cotton dust and lung function; which has implications for regulations and standards in the textile industry in Pakistan and similar cotton-processing countries.

Background: Obesity and overweight are associated with work absenteeism of medical cause. However, there is little knowledge on the relationship between incremental body mass index (BMI) and absenteeism.Objective: To assess the effect of annual increase in BMI on amount of prolonged absenteeism.Methods: Data from a longitudinal historical cohort of workers of a mining camp in Peru between 2006 and 2014 were used for the analysis. Prolonged absenteeism of 30 days or more in one year was chosen as the dependent variable; annual increase in BMI was considered as the explanatory variable. Regression analysis with generalized estimating equation was used to determine the relative risk adjusted for age, sex and type of work.Results: There were 1347 cases of medical leave reported with a median of 6 days. Of all cases of medical leave, 11% of those who had an annual increase in BMI and 6% of those who maintained their BMI were cases of prolonged absenteeism. Prolonged absenteeism significantly increased in workers who had an annual increment in BMI (adj RR 1.16, 95% CI 1.05 to 1.29).Conclusion: The annual increase in BMI was marginally associated with prolonged absenteeism. Temporal increment in BMI, regardless of the baseline BMI, may be an independent determinant of the work absenteeism of medical cause.

Background: Children living in agricultural areas are at risk of exposure to pesticides due to their involvement in agricultural activities. Pesticides are one of the chemicals classified as endocrine disrupting chemicals.Objective: To examine the association between exposure to organophosphate pesticides and the occurrence of thyroid dysfunction in children.Methods: This cross-sectional study was conducted on 66 children in two elementary schools located in an agricultural area in Brebes District, Indonesia, in 2015. To determine the pesticide exposure history, we analyzed urine samples and completed a questionnaire. Meanwhile, thyroid function tests were performed.Results: Organophosphate pesticide metabolites were detected in urine samples of 15 (23%) of 66 children. Thyroid stimulating hormone (TSH) levels>4.5 mIU/mL were detected in 24 (36%) children. Free thyroxine (FT4) levels of all participants were normal. The mean TSH level in children with positive urinary organophosphate pesticide metabolites (7.74 mIU/ mL) was significantly (p=0.005) higher than that in those who were negative (4.34 mIU/mL). The prevalence of hypothyroidism in children with positive urinary organophosphate pesticide metabolites (67%) was significantly higher than that in those who were negative (27%; PR 2.4, 95% CI 1.4 to 4.3).Conclusion: A history of pesticide exposure could be used as a risk factor for the occurrence of thyroid dysfunction in children living in agricultural areas.

Background: Exposure to benzene would be associated with many diseases including leukemia. Epigenetic alterations seem to be among the main mechanisms involved.Objective: To determine if chronic occupational exposure to low level of benzene would be associated with DNA methylation.Methods: Global DNA methylation and promoter-specific methylation of the two tumor suppressor genes, p14ARF and p15INK4b, were assessed employing methylation-specific PCR using the DNA extracted from 40 petrochemical workers exposed to ambient benzene levels of<1 ppm, and 31 office workers not exposed to benzene or its derivatives.Results: While an increase in global DNA methylation of 5% in p14ARF (p=0.501) and 28% in p15INK4b (p=0.02) genes was observed in the exposed group, no hyper methylation in either of the studied genes was observed in the unexposed group. No significant association was found between the frequency of aberrant methylation and either of age, work experience, and smoking habit in the exposed group.Conclusion: Chronic occupational exposure to lower than the permissible exposure limit of benzene may still result in DNA methylation of tumor suppressor genes that may ultimately lead to development of cancer.

From April 28 to May 28, 2018, more than 1200 patients with impression of mushroom poisoning were referred to hospital emergency departments in 13 west and northwestern provinces, Iran; 112 (8.9%) patients were hospitalized and 19 were expired (ie, a fatality rate of 1.5%). The outbreak began in Kermanshah province with increasing number of patients presenting with severe abdominal pain, nausea, vomiting, and diarrhea soon after consumption of wild mushrooms. Lepiota brunneioncarnata, Hypholoma fascicalare, and Coprinopsis atramentaria have been involved in this outbreak. To prevent similar outbreaks, raising public awareness about risky behaviors of collecting and consuming wild self-picked mushrooms is of paramount importance. Herein, we present our experience with this outbreak.

Dear Editor: We read with interest the article on the measurement of lung cancer tumor markers in a group of workers exposed to respirable synthetic vitreous fiber (SVF) and dust, recently published in the IJOEM...