Investigation of three different UV-C irradiation schemes for bacterial decontamination of FFP2 masks to make them reusable

The effect of FFP2 masks for infection prevention is essential in healthcare systems, however, depending on supply chains. Efficient methods to reprocess FFP2 masks may be needed in disasters. Therefore, different UV-C irradiation schemes for bacterial decontamination of used FFP2 masks were investigated.78 masks were irradiated with UV-light for durations between three and 120 seconds and subsequently analysed for the presence of viable bacteria on the inside. 10 masks served as control group. Irradiation on the inside of the masks reduced bacteria in proportion to the dose, with an almost complete decontamination after 30 seconds. Outside irradiation reduced the quantity of colonies without time dependent effects. Both side irradiation for cumulated 30 seconds or more showed almost complete decontamination.Overall, this study suggests that standardized UV irradiation schemes with treatment to both sides might be an efficient and effective method for FFP2 mask decontamination in times of insufficient supplies.

Environmental and Occupational Exposures and Prognosis in Patients with Non-Muscle Invasive Bladder Cancer in the Be-Well Study

Bladder cancer is primarily diagnosed as non-muscle invasive bladder cancer (NMIBC) with high recurrence and progression rates. Environmental and occupational exposures to carcinogens are well-known risk factors for developing bladder cancer, yet their effects on prognosis remain unknown. In the Be-Well Study, a population-based prospective cohort study of 1,472 patient with newly diagnosed NMIBC from 2015 to 2019, we examined history of environmental and occupational exposures in relation to tumor stage and grade at initial diagnosis by multivariable logistic regression, and subsequent recurrence and progression by Cox proportional hazards regression. Exposure to environmental and occupational carcinogens was significantly associated with increased risk of progression (HR = 1.79; 95% CI: 1.04, 3.09), specifically increased progression into muscle-invasive disease (HR = 2.28; 95% CI: 1.16, 4.50). Exposure to asbestos and arsenic were associated with increased odds of advanced stage at diagnosis (asbestos: OR = 1.43; 95% CI: 1.11, 1.84; arsenic, OR = 1.27; 95% CI: 1.01, 1.63), and formaldehyde exposure was associated with increased risk of recurrence (HR = 1.38; 95% CI: 1.12, 1.69). Our findings suggest that history of these exposures may benefit current risk stratification systems to tailor clinical care and improve prognosis in patients with NMIBC.

[Occupational disease by COVID-19 in healthcare workers]

Background

1 out of 5 cases of COVID-19 in Mexico occurred in health workers, and the high risk of contagion in these workers caused absenteeism due to temporary leave from work (TLfW), as well as the need to establish qualification criteria for COVID-19 as an occupational disease (OD). There are no quantitative data about the labor population to whom this benefit has been provided, nor on the economic impact of not being qualified as OD.

Objective

To estimate the prevalence of qualification of OD by COVID-19 in health workers from a tertiary care hospital (TCH).

Material and methods

Descriptive, cross-sectional, and retrospective study carried out from March 2020 to April 2021, which included health workers from a TCH who had TLfW due to COVID-19 and were working 14 days before it was issued. Variables such as OD, days of TLfW, category, among others, were analyzed, as well as the economic income lost by remaining as a general disease (GD). It was used descriptive statistics.

Results

A total of 654 health workers had TLfW due to COVID-19, with a prevalence of OD of 18.5%; 17 days of TLfW were granted on average. Nurses were classified with the high number of OD, and the category with the highest prevalence was cleaning and hygiene assistant (36%). 5310 days of TLfW were subsidized as GD, equivalent to $510,385.60 (Mexican pesos) that were not granted as an economic benefit to the population that did not have an OD qualification due to COVID-19.

Conclusions

The prevalence of recognition of COVID-19 as OD was low; most of TLfWs were subsidized as GDs.

[Noise pollution in the working environment]

NOISE POLLUTION IN THE WORKING ENVIRONMENT. Hearing damage due to exposure to noise in the workplace has been recognised as a professional disease since 1963. It first manifests itself as auditory fatigue, which can be assessed by Echoscan and which requires preventive measures, before bilateral hearing loss sets in, usually symmetrical, initially producing a very characteristic auditory scotoma centred on the 4000 Hz frequency. This irreversible hearing loss may be accompanied by tinnitus, more rarely by hyperacusis, as well as other extra-auditory manifestations: stress, high blood pressure or sleep disorders. The regulations aimed at protecting workers against noise trauma impose collective measures, the wearing of individual protectors and, above all, hearing monitoring every two years. Recognition as a professional disease of hearing damage resulting from professional exposure to noise damage enables the worker to be compensated and to be helped in the acquisition of hearing aids, if prescribed.

Evaluation of Temporal Trends of Lead Exposure in Korean Workers Using Workplace Monitoring Data

BACKGROUND

Lead, which is widely used in various industrial settings, is a major health hazard for manufacturing workers. Therefore, control of lead exposure has been implemented in an effort to prevent lead-related health problems. In this study, our aim was to evaluate temporal trends in occupational lead exposure in Korean lead workers using data from monitoring of workplace exposure.

METHODS

A nationwide work environment monitoring database, data from a work environment monitoring institution, and data extracted from a review paper were utilized. Different versions of standard industrial classification codes were aligned with the 10th Korean Standard Industrial Classification, which is generally consistent with the 4th revision of the International Standard Industrial Classification. The multiple data sources were combined and temporal trends over the period from 1994-2021 were estimated. In addition, separate estimation of temporal trends in the storage battery manufacturing industry over the period from 1987-2021 was also performed.

RESULTS

A total of 444,296 personal airborne lead measurements were used for the estimation process. The temporal trends in occupational exposure to lead declined by -6% annually over the study period. In particular, levels of lead exposure in the storage battery manufacturing industry showed a steeper decline of -12% annually.

CONCLUSIONS

Findings of our study showed that occupational exposure to lead declined over the period from 1994 to 2021 in Korea. However, adverse effects of exposure to lead on health should be regarded with caution. The results will be useful in conduct of epidemiological studies examining lead-related effects on health.

Identification of Asymptomatic Severe Acute Respiratory Syndrome Coronavirus 2 Infections Among Healthcare Workers at Sultan Qaboos University Hospital, Oman

Objectives

This study aimed to describe the incidence and features of asymptomatic COVID-19 infections among healthcare workers (HCWs) at a tertiary hospital in Oman.

Methods

This cross-sectional study was conducted between August 2020 and February 2021 among HCWs with no history of COVID-19 infection. An online questionnaire collected sociodemographic and clinical data. COVID-19 infection was diagnosed using nasopharyngeal/throat swabs, which were tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Analyses were performed using the Chi-squared test, Fisher's exact test or univariate ordinary least squares regression, as appropriate.

Results

A total of 583 HCWs participated in the study, most of whom were female (56.6%), and the mean age was 35 ± 8 years. Only 9.6% (95% confidence interval [CI]: 7.3-12.3%) of the HCWs were at high exposure risk as they were directly involved in the care of COVID-19-infected patients. Overall, 4.1% (95% CI: 2.7-6.1%) of the HCWs screened positive for SARS-CoV-2, of which 20.8% developed symptoms within two weeks. The frequency of SARS-CoV-2 positivity among HCWs working in high-, intermediate-, low- and miscellaneous-risk areas was 1.8% (95% CI: <0.1-9.6%), 2.6% (95% CI: <0.1-6.5%), 5.3% (95% CI: 0.3-9.3%) and 4.8% (95% CI: <0.1-69.3%), respectively. Working in high-risk areas was associated with increased compliance with various infection control strategies (P <0.001).

Conclusion

There was a greater frequency of SARS-CoV-2 positivity among HCWs working in low-risk areas, whereas HCWs who worked in high-risk areas were significantly more likely to report increased compliance with infection control strategies.

Effect of Occupational Noise Exposure on the Prevalence of Benign Vocal Fold Lesions: A Nationwide Population-Based Study

OBJECTIVES

Voice abuse in noisy environments can result in voice disorders. However, insufficient studies have sought to differentiate vocal cord lesions through laryngoscopic examinations among workers in noisy environments. This study investigated the relationship between a history of noise exposure in the workplace and benign vocal fold lesions (BVFLs).

METHODS

We used Korea National Health and Nutrition Examination Survey data from 2010 to 2012. The chi-square test was used to compare characteristics between two groups according to the presence or absence of BVFLs. To investigate the association between BVFLs and noise exposure in the workplace, we calculated adjusted odds ratios and 95% confidence intervals (CIs) using multiple logistic regression analysis.

RESULTS

In total, 10,170 participants with available laryngoscopy.

RESULTS

were enrolled. Smoking history, hypertension, diabetes, and exposure to noise for more than 3 months at the workplace were significantly more common in participants with BVFLs. After adjusting for age, sex, smoking, drinking, obesity, hypertension, diabetes, income, education, and occupation as confounders, we confirmed that BVFLs were 1.52 times more likely (95% CI, 1.157-1.990) to occur in individuals with occupational noise exposure.

CONCLUSION

Working in a noisy environment could induce BVFLs in workers through voice abuse. Social recognition that a noisy environment is a risk factor for BVFLs needs to be improved, and preventive measures should be implemented.

Evaluation of general health, exposure to workplace violence, and predicting its consequences in health care employees in Iran

BACKGROUND

Workplace violence is an important event that affects the safety of healthcare employees, and diagnosing it in hospitals is an immediate occupational concern.

OBJECTIVE

The present study was conducted to investigate general health and the prevalence of occupational violence and to predict its consequences among nurses and paramedics as the main body in medical settings.

METHODS

This cross-sectional study was performed in 2020 in a selected hospital in Tehran, Iran. A total of 208 healthcare workers participated in the study. To study general health, exposure to workplace violence, job burnout, and productivity, the general health questionnaire (GHQ), the workplace violence questionnaire, the Maslach burnout questionnaire, and the workforce productivity questionnaire were provided to healthcare workers, respectively. Then, a multiple linear regression model was used to predict violence and its consequences.

RESULTS

The results revealed that 34.1% of the participants have psychological disorders, and 74.5% have experienced one type of violence in their workplace at least once during the past year. The multiple linear regression model results indicated that workplace violence prevalence proved the ability to predict the increase in burnout and decrease in job productivity.

CONCLUSION

Exposure to violence in the workplace significantly increases the risk of mental disorders associated with the risk of mental illness. Therefore, managing exposure to violence in the workplace is a practical step in improving general and mental health and ultimately increasing job productivity in medical settings.

[Analysis of occupational health examination status of people exposed to vinyl chloride]

Objective: To investigate the detection of occupational health for vinyl chloride workers in Tianjin. Methods: In this study, we have collected data from 7 companies with vinyl chloride hazards in 16 districts of Tianjin. Finally, the occupational health surveillance data of 478 vinyl chloride-exposed workers were included in the analysis. Quantitative data was tested for normality. If the data conforms to the normal distribution, using the Mean±SD for statistical description, and t test for statistical analysis. If the data does not conform to the normal distribution, using Median (Q(1), Q(100)) for statistical description, rank sum test for statistical analysis. The qualitative data was described by composition ratio, and the chi-square test was used for statistical analysis. The logistic regression was used to assess the impact on suspected occupational disease and occupational contraindication from personal general conditions, occupational history, company information. Results: The abnormal detection rate of vinyl chloride monomer workers in Binhai New Area was higher than that in other areas (χ(2)=5.20, P=0.023). The abnormal detection rate of vinyl chloride monomer workers in non manufacturing industries was higher than that in manufacturing industries (χ(2)=7.74, P=0.005). The abnormal detection rate of vinyl chloride monomer workers in domestic enterprises was higher than that in foreign invested enterprises (χ(2)=22.38, P<0.01). Compared with the normal group of vinyl chloride monomer workers, the abnormal group of workers was older and had longer working years, The difference was statistically significant (Z=-3.32, -3.54, P=0.001, <0.01). The employer of vinyl chloride monomer workers is in Binhai New Area, the economic type is domestic funded enterprise, the industry is classified as non manufacturing industry, the age is more than 40 years old, and the length of service is more than 20 years old, which is the influencing factor for workers to detect abnormalities (OR=1.875, 95%CI: 1.279~2.749; OR=1.657, 95%CI: 1.071~2.563; OR=3.562, 95%CI: 2.057~6.170; OR=2.166, 95%CI: 1.245~3.768; OR=1.968, 95%CI: 1.345~2.879, all P<0.05) . Conclusion: To protect the health of workers and prevent occupational diseases, the management of vinyl chloride exposure on production process, especially in domestic enterprise, should be improved. Also, better occupational health surveillance should be provided to female workers.

The Association between Duration of Noise Exposure in the Workplace and Glucose Metabolism Status: Evidence from the Korea National Health and Nutrition Examination Survey

BACKGROUND

This study aimed to evaluate the association between the duration of workplace noise exposure and glucose metabolism status in a nationally representative Korean sample.

METHODS

This cross-sectional study included 3,534 participants aged ≥40 years without tinnitus or hearing loss from the Korea National Health and Nutrition Examination Survey (2018). The primary exposure was noise in the workplace and its duration. We divided the noise exposure group into four groups according to the duration of noise exposure (<3 years, 3-10 years, 10-20 years, and ≥20 years). The primary outcomes were fasting blood sugar (FBS), hemoglobin A1c (HbA1c), and pre-diabetes and diabetes diagnosed using FBS. Logistic and linear regression analyses were used to test the association between noise exposure and glycemic status.

RESULTS

After adjustment, HbA1c levels were significantly higher in the noise exposure than in the non-noise exposure group. HbA1c levels were significantly higher in those exposed to occupational noise for more than 20 years than in others. In the subgroup analysis among those who had been exposed to noise for >20 years, the non-aerobic physical activity group had significantly higher HbA1c levels than the physical activity group. Furthermore, among those who had been exposed to noise for >20 years, the without hearing protection group had significantly higher HbA1c levels than those using hearing protection.

CONCLUSION

The association between noise exposure and the prevalence of diabetes is unclear. However, our study clearly suggests that there is a relationship between elevated HbA1c levels and workplace noise exposure and that a long period of workplace noise exposure, no physical activity, and not wearing a hearing protection device could increase the risk of diabetes.

[End of career and end of exposure visits]

END-OF-CAREER AND END-OF-EXPOSURE VISITS Many legislative changes have been introduced in recent months concerning the activity of occupational physicians. Particular emphasis has been placed on the traceability of exposure and the resulting medical follow-up with the creation of end-of-career and end-of-exposure visits. These new features imply changes in terms of post-occupational monitoring in particular, but other appointments are obviously possible for workers in conjunction with their prevention and occupational health service.

Nitrous oxide occupational exposure in conscious sedation procedures in endoscopic ambulatories: a pilot retrospective observational study in an Italian hospital

SUMMARY

Introduction. Nitrous oxide (N2O) is widely used to induce sedation also outside of operating rooms; there is a chance of workplace exposures for the operators engaged in the outpatient use of nitrous oxide. The aim of this research is to assess nitrous oxide exposure in gastroenterology outpatient settings. Methods. We performed an observational study marked by N2O environmental testing in a gastroenterology outpatient care; environmental research was supported by biological monitoring with urinary N2O analysis in exposed operators. The research was conducted both without and using a collective security device (NIKI mask). Results. The study was rolled out in 10 sessions of day shift procedures, totaling 4105 samples. The average N2O concentration in the environment was 27.58 (SD 1.76) and 449.59 (SD 35.29), respectively with and without NIKI Mask; the distribution of gases in the environment under investigation was not homogeneous (Anovatest P=0.001). Biological testing revealed a substantial rise in urinary concentration of 8.97 (p=0.001) between the start and the end of the shift, and the use of the NIKI-mask was effective (p=.003). Discussion. The exposure levels reported exceed the limits of 50 ppm (Italy operating rooms threshold value) as well as the value of 25 ppm (NIOSH threshold-value), indicating a significant issue in the outpatient use of N2O. Technical measures are needed to contain the occupational risk from N2O exposure outside of operating rooms; for the exposure results detected in this research, it is also evident that workers exposed to N2O must be subject to adequate health surveillance accounting for this occupational risk.

Occupational cold exposure and symptoms of carpal tunnel syndrome - a population-based study

BACKGROUND

Cold exposure is an underrecognized occupational hazard that may increase the risk of peripheral nerve entrapment. The aim of this study was to determine if self-reported occupational exposure to contact and ambient cooling was associated with symptoms of carpal tunnel syndrome (CTS).

METHODS

In this mainly cross-sectional study, surveys were conducted on a population-based sample of men and women between 18 and 70 years of age, living in northern Sweden. Cold exposure and presence of symptoms suggestive of CTS were subjectively reported. Associations between exposure and outcome were evaluated using logistic regression.

RESULTS

The study included 2,703 women and 2,314 men, with a median age of 60 years (interquartile range 19). Symptoms of CTS were reported by 453 (9.2%). Being highly occupationally exposed (almost always) to contact cooling of the hands was associated with reporting CTS (OR 3.20; 95% CI 1.62-6.33), as was ambient cooling (OR 2.00; 95% CI 1.03-3.88) and severe ambient cooling (OR 4.02 95% CI 2.09-7.71), after adjusting for age, gender, body mass index, current daily smoking, diabetes mellitus, joint disease, and hand-arm vibration exposure. The point estimates increased with longer daily exposure duration. For workers exposed to severe ambient cooling for more than half of their working hours, in addition to performing heavy manual handling every day, the OR for reporting CTS was 7.25 (95% CI 3.88-13.53), with a positive additive interaction effect (expressed as relative excess risk due to interaction) of 4.67.

CONCLUSIONS

Self-reported occupational exposure to contact and ambient cooling was associated with symptoms suggestive of CTS. There were statistically significant positive exposure-response patterns for time spent exposed to contact and ambient cooling at work in relation to reporting symptoms of CTS. Positive additive interaction effects between cold exposure and heavy manual handling were also found. Since there was important potential uncontrolled confounding regarding repetitive wrist movements and forceful gripping, the results need to be confirmed by other studies, preferably with longitudinal design and more detailed exposure assessment.

Identifying non-hazardous substances in pharmaceutical manufacturing and setting default Health-Based Exposure Limits (HBELs)

Contract Development and Manufacturing Organizations (CDMOs) that manufacture large, diverse portfolio of chemical and pharmaceutical substances require pragmatic risk-based decisions with respect to the safe carry-over between different chemical entities, as well as for worker protection. Additionally, CDMOs may not have access to primary study data or data is generally lacking for a specific substance. While pharmaceuticals require the establishment of health-based exposure limits (HBELs) (e.g., occupational exposure limits, permitted daily exposure limits), the limits for non-hazardous substances could be set in a protective and pragmatic way by using default values, when internally required. Since there is no aligned definition provided by authorities, nor agreed default values for non-hazardous substances, we provide a decision tree in order to help qualified experts (such as qualified toxicologists) to identify the group of non-hazardous substances and to assign default HBEL values for specific routes of exposure. The non-hazardous substances discussed within this publication are part of the following subgroups: (I) inactive pharmaceutical ingredients, (II) pharmaceutical excipients or cosmetic ingredients, (III) substances Generally Recognized as Safe (GRAS), and (IV) food ingredients, additives and contact materials. The proposed default limit values are 1 mg/m³ for the OEL, and 50 mg/day for the PDE oral and IV (intravenous) route.

Prevalence of Occupational Exposure to HIV and Factors Associated with Compliance with Post-Exposure Prophylaxis Among Health Workers of the Biyem-Assi, Buea, and Limbe Health Districts of Cameroon Maternal and Child Health and AIDS

BACKGROUND

Although a few studies have assessed occupational exposure and knowledge on post-exposure prophylaxis (PEP) for HIV among health care workers (HCWs), limited information is available on the factors that influence the use of HIV PEP among HCWs after occupational exposure in Cameroon. This study aimed to assess the prevalence and determinants of occupational exposure to HIV infection and identify factors (knowledge, attitudes, and practices) that influence compliance to the use of HIV PEP among HCWs in the Biyem-Assi, Buea, and Limbe health districts.

METHODS

A stratified cross-sectional study was carried out among health care workers from the Biyem-Assi, Buea, and Limbe health districts of Cameroon. A structured questionnaire adapted from previous studies was administered on the socio-demographic status, occupational exposure to biological agents as well as information on knowledge, awareness of PEP guidelines, attitude, and practice of the HCWs towards HIV PEP.

RESULTS

Of the 312 participants, 198 (63.5%) experienced an occupational injury, and 240 (76.9%) had a good attitude towards HIV PEP. Age, place of work, and inadequate knowledge were determinants of occupational exposure. Whereas, awareness of PEP guidelines and being a medical doctor influenced compliance with HIV PEP, with 158 (51.0%) having adequate knowledge of the guidelines. Out of the 198 who experienced occupational injury, 114 (57.6%) adopted the good practice and 60 (30.3%) made use of HIV PEP.

CONCLUSION AND GLOBAL HEALTH IMPLICATIONS

Over half of health care workers had occupational exposure to HIV with poor utilization of post-exposure prophylaxis though they were aware and knowledgeable of PEP guidelines and exhibited good practice. Compliance with HIV PEP utilization was influenced by gender, awareness of PEP guidelines, and specialty of the health care worker.

Aflatoxin B1: metabolism, toxicology, and its involvement in oxidative stress and cancer development

Aflatoxins are a class of carcinogenic mycotoxins produced by Aspergillus fungi, which are widely distributed in nature. Aflatoxin B1 (AFB1) is the most toxic of these compounds and its metabolites have a variety of biological activities, including acute toxicity, teratogenicity, mutagenicity and carcinogenicity, which has been well-characterized to lead to the development of hepatocellular carcinoma (HCC) in humans and animals. This review focuses on the metabolism of AFB1, including epoxidation and DNA adduction, as it concerns the initiation of cancer and the underlying mechanisms. In addition to DNA adduction, inflammation and oxidative stress caused by AFB1 can also participate in the occurrence of cancer. Therefore, the main carcinogenic mechanism of AFB1 related ROS is summarized. This review also describes recent reports of AFB1 exposures in occupational settings. It is hoped that people will pay more attention to occupational health, in order to reduce the incidence of cancer caused by occupational exposure.

Ergonomic Stressors Among Pregnant Healthcare Workers: Impact on pregnancy outcomes and recommended safety practices

Workplace environment can have a considerable impact on the physical, psychological and maternal health of pregnant healthcare workers. This article aimed to summarise the impact of work-related ergonomic stressors on pregnancy outcomes for healthcare workers, along with potential interventions to resolve these stressors. A narrative review analysis using the Pearl Growing Strategy was conducted between February 2019 and June 2020 to identify English-language articles published between 2000 and 2020. A total of 89 studies were identified from the SCOPUS (Elsevier, Amsterdam, Netherlands), MEDLINE® (National Library of Medicine, Bethesda, Maryland, USA) databases and Google Scholar (Google LLC, Menlo Park, California, USA). The results indicated that poor work-related ergonomics had detrimental effects on pregnancy outcomes, resulting in spontaneous abortions, preterm delivery, low birth weight babies and infertility. Policymakers and employers should conduct ergonomic assessments and implement appropriate practices to ensure the safety of pregnant healthcare workers.

Prevalence of Lyme Disease Attributable to Military Service at the USMA, West Point NY: FY2016-2018

INTRODUCTION

Lyme disease incidence rates have steadily increased since its official recognition in 1975. Since exposure to Lyme is associated with activities conducted in and around tick-habitats including tall grass, shrubs, deciduous forest, and leaf litter, it has been suggested that service members, who are thought to spend higher amounts of time in these habitats due to training requirements, may have higher risk for exposure. Specifically, this study looks at service member and family member exposure to Ixodes scapularis, the vector for Lyme in the Northeastern and Midwestern United States. While literature pertaining to occupational and military specific exposures to Lyme vectors have attempted to quantify the possible elevated risk of Lyme disease for service members, thus far, studies have not consistently confirmed that service members are at a greater risk than family members.

MATERIALS AND METHODS

This cross-sectional study looks at cases of Lyme disease at Keller Army Community Hospital (KACH) on the West Point Military Reservation in New York during Fiscal Year (FY) 2016 through FY2018. Lyme cases were pulled from Military Health System Mart using current ICD-10-CM codes for Lyme related conditions (A69.20 and A69.29). In total, 144 cases were considered for the analysis. Totaling all service members and family members enrolled at KACH over the three-year period account for 35,526 person-years. Period prevalence, attributable risk percentage, population attributable risk percentage, and corresponding 95% confidence intervals were calculated for service members and family member categories. This study was conducted on human subject research according to 32CFR219 and meets the requirements of exempt status under 32CFR219.101(b)(4) because it is a cross-sectional study on existing de-identified patient data.

RESULTS

During FY2016-2018, service members accounted for 63 cases of Lyme totaling 21,595 person-years with a period prevalence of 292 cases per 100,000 (219.8, 363.7). Family members accounted for 81 cases with a total of 13,931 person-years with a period prevalence of 581 cases per 100,000 (455.2, 707.7). The percentage of attributable risk during the three-year period credited to military status is -99.30% (-145.69%, -52.91%). The population attributable risk percentage is -43.4%.

CONCLUSIONS

While this study was unable to capture the military specific occupational exposure to I. scapularis, it does show a difference in period prevalence between service members and family members with the family members being at higher risk to contract Lyme instead of service members as is commonly suggested in the literature. Additional studies may be conducted to see if this holds true across service member Military Occupational Specialties as a proxy for occupational exposure. Similar studies should be conducted at military installations situated in Lyme endemic areas to determine if these results are comparable across the military or specific to West Point. Future research should attempt to identify all the service member protective factors against Lyme with attribution to permethrin-treated uniforms and other military interventions designed to defend soldiers against vector-borne diseases.

[Predictors of Blood and Body Fluid Exposure and Mediating Effects of Infection Prevention Behavior in Shift-Working Nurses: Application of Analysis Method for Zero-Inflated Count Data]

PURPOSE

This study aimed to identify the predictors of blood and body fluid exposure (BBFE) in multifaceted individual (sleep disturbance and fatigue), occupational (occupational stress), and organizational (hospital safety climate) factors, as well as infection prevention behavior. We also aimed to test the mediating effect of infection prevention behavior in relation to multifaceted factors and the frequency of BBFE.

METHODS

This study was based on a secondary data analysis, using data of 246 nurses from the Shift Work Nurses' Health and Turnover study. Based on the characteristics of zero-inflated and over-dispersed count data of frequencies of BBFE, the data were analyzed to calculate zero-inflated negative binomial regression within a generalized linear model and to test the mediating effect using SPSS 25.0, Stata 14.1, and PROCESS macro.

RESULTS

We found that the frequency of BBFE increased in subjects with disturbed sleep (IRR = 1.87, p = .049), and the probability of non-BBFE increased in subjects showing higher infection prevention behavior (IRR = 15.05, p = .006) and a hospital safety climate (IRR = 28.46, p = .018). We also found that infection prevention behavior had mediating effects on the occupational stress-BBFE and hospital safety climate-BBFE relationships.

CONCLUSION

Sleep disturbance is an important risk factor related to frequency of BBFE, whereas preventive factors are infection prevention behavior and hospital safety climate. We suggest individual and systemic efforts to improve sleep, occupational stress, and hospital safety climate to prevent BBFE occurrence.

PCDD/Fs in paired hair and serum of workers from a municipal solid waste incinerator plant in South China: Concentrations, correlations, and source identification

Human hair has been widely used to evaluate the exposure to drugs and organic pollutants. However, reports on the relationship between polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzo-p-furans (PCDFs) in hair and the body burden of PCDD/Fs are limited. In this study, the association between PCDD/Fs in paired hair and serum samples from workers was examined in a municipal solid waste incinerator (MSWI) plant in South China. Fly ash and flue gas from the MSWI plant were also analyzed to determine the source apportionment of PCDD/Fs in the hair. The median international toxic equivalents (I-TEQs) of ΣPCDD/F in serum and hair were 28.0 pg TEQ/g (lipid weight) and 0.30 pg TEQ/g (dry weight), respectively. The indicator congener of PCDD/Fs for the TEQ levels was 2,3,4,7,8-pentachlorodibenzofuran (PeCDF) in both hair and serum, the concentrations of which both exhibited significant and strong linear dependence on the total TEQ levels (p < 0.01, R² = 0.966 and R² = 0.670, respectively). Significant positive correlations were found in the 1,2,3,6,7,8-hexachlorodibenzo-p-dioxin (HxCDD) and octachlorodibenzo-p-dioxin (OCDD) levels between the hair and serum samples (p < 0.05). Flue gas (which is an external source) was identified as the primary source of PCDD/Fs in human hair. Blood and flue gas were accountable for, on average, 37% and 61% of the PCDD/Fs in hair, respectively.

[Occupational accidents by biological risk in clinical laboratory workers. Yopal, Colombia]

BACKGROUND

Clinical laboratory workers are at permanent risk of suffering an occupational accident due to exposure to biohazard. These accidents may cause severe diseases, such as HIV, HBV or HCV.

OBJECTIVE

To describe the behavior of accidents due to occupational exposure to biohazard agents, and the characteristics of reports of occupational accidents in clinical laboratories in Yopal, Colombia.

MATERIAL AND METHODS

Observational descriptive study with exploratory component and retrospective analysis of incident report forms of presumed occupational accidents.

RESULTS

For the period between January 1, 2016, to December 31, 2018, an occupational accident percentage of 24.6 (95% confidence interval [95% CI], 16.7-32.5) was estimated, and an underreporting percentage of 39.3 (95% CI, 21.3-57.3). The main reasons for not reporting were a perceived lack of time (45.4%), and a diminished perception of risk exposure (36.4%). In contrast, factors associated with the probability of having less occupational accidents included being hired for service time (prevalence ratio [PR] = 0.19; 95% CI, 0.04-0.89; p = 0.034), and the permanent use of personal protective equipment (PR = 0.14; 95% IC, 0.02-0.88; p =0.036).

CONCLUSION

Accident statistics in clinical laboratories prove the necessity to systematically reorganize risk management strategies that take into account human factor, organizational culture and control mechanisms.

Respiratory Symptoms and Diminished Lung Functions Associated with Occupational Dust Exposure Among Iron Ore Mine Workers in Iran

Background:

Dust exposure at quarry mines is inevitable and can result in poor air quality. This research aimed to assess pulmonary symptoms and lung functions of dust-exposed workers at an iron-ore mine in eastern Iran.

Methods:

An environmental cross-sectional study sampled 174 dust-exposed mine workers and 93 unexposed administrative employees as the reference group. A standardized questionnaire on respiratory symptoms was completed in accordance with recommendations of the American Thoracic Society(ATS). Calibrated spirometer measured Pulmonary Function Tests (PFTs). Data were analyzed via SPSS-21, integrating independent samples t-test, Chi-square and linear or logistic-regression models.

Results:

There was no significant variation between dust-exposed and reference groups in terms of age, weight, height, work experience and the number of smokers (P>0.05). Mean levels of exposure to inhalable and respirable mineral-dust were 15.09±2.34 and 3.45±2.57 mg/m³ respectively. Pulmonary capacities of dust-exposed group were considerably decreased as compared to others (Forced Vital Capacity [FVC] 86.55±13.77 vs. 105.05±21.5; Forced Expiratory Volume in 1 second [FEV1] 88.06±16.8 vs. 105.81±21.55; FEV1/FVC 103.03±18.17 vs. 93.3±12.49; and Peak Expiratory Flow [PEF] 89.82±22.58 vs. 98.09±20.60) (P<0.001); with a higher prevalence of cough (P=0.041), wheezing (P=0.032), and dyspnea (P=0.035) among formers. Age along with exposure to respirable-dust significantly reduced FVC, FEV1 and FEV1/FVC. Cigarette consumption attenuated FVC and FEV1 on an average of 5 to 9 units.

Conclusion:

Controlled occupational dust-exposure is a definitive pre-requisite to reduce respiratory problems among quarry workers, with an explicit consideration towards mineral- mine workers. Modifiable accomplices like smoking and non-compliance of PPEs usage should be amicably resolved.

Assessment of Adaptive Response of Gamma Radiation in the Operating Room Personnel Exposed to Anesthetic Gases by Measuring the Relative Gene Expression Changes Ku80, Ligase1 and P53

Background

Some operating room personnel are occupationally exposed to genotoxic agents such as anesthetic gases and ionizing radiation. Adaptive response, as a defense mechanism, will occur when cells become exposed to a low dose of factors harming DNA (priming dose), which in the subsequent exposure to higher dose of those factors (challenging dose), show more resistance and sensibility.

Objective

The aim of this study was to investigate adaptive response or synergy of ionizing radiation in the operating room personnel exposed to anesthetic gases by evaluation of the relative gene expression changes of effective genes for DNA repair such as Ku80, Ligase1 and P53.

Material and Methods

In this case-control study, 20 operating room personnel and 20 nurses (who were not present in the operating room) as controls were studied. Venous blood samples were drawn from participants. In order to evaluate the adaptive response, a challenging dose of 2Gy gamma radiation was applied to blood samples. Moreover, RNA extraction and cDNA synthesis were performed. Gene expression level was studied by RT-qPCR and compared with the control group.

Results

Ligase1 and P53 expression in the operating room personnel was significantly higher than that of the control group before irradiation (P˂0.001). Statistically, there was no significant difference in the Ku80 and P53 expression in the operating room personnel before and after irradiation.

Conclusion

Given the findings of this study, exposure to challenging dose of gamma radiation can induce adaptive response in expression of Ku80 and P53 genes in operating room personnel.

Gender differences in respiratory health outcomes among farming cohorts around the globe: findings from the AGRICOH consortium

Purpose: Respiratory hazards of farming have been identified for centuries, with little focus on gender differences. We used data from the AGRICOH consortium, a collective of prospective cohorts of agricultural workers, to assess respiratory disease prevalence among adults in 18 cohorts representing over 200,000 farmers, farm workers, and their spouses from six continents.Methods: Cohorts collected data between 1992 and 2016 and ranged in size from 200 to >128,000 individuals; 44% of participants were female. Farming practices varied from subsistence farming to large-scale industrial agriculture. All cohorts provided respiratory outcome information for their cohort based on their study definitions. The majority of outcomes were based on self-report using standard respiratory questionnaires; the greatest variability in assessment methods was associated with chronic obstructive pulmonary disease (COPD).Results: For all three respiratory symptoms (cough, phlegm, and wheeze), the median prevalence in men was higher than in women, with the greatest difference for phlegm (17% vs. 10%). For asthma, women had a higher prevalence (7.8% vs 6.5%), with the difference associated with allergic asthma. The relative proportion of allergic asthma varied among cohorts. In two of eight cohorts for women and two of seven cohorts for men, allergic asthma was more common than non-allergic asthma.Conclusions: These findings indicate that respiratory outcomes are common among farmers around the world despite differences in agricultural production. As women in the general population are at higher risk of asthma, exploring gender differences in occupational studies is critical for a deeper understanding of respiratory disease among agricultural workers.

[Diffuse Intraparenchymal Mesothelioma: An Atypical Presentation]

Pleural mesothelioma is a disease associated with exposure to asbestos. Although rare, it is the most common malignant pleural neoplasm. It is difficult to diagnose and it has a poor prognosis. We report the case of a 62-year-old male patient with a history of prolonged occupational exposure to asbestos, with dyspnea for minor exertion and productive cough, for several months. Imaging studies revealed extensive interstitial involvement with marked thickening of the interlobular and centrilobular septa and tenuous pleural involvement. Several differential diagnoses were considered such as, asbestosis, cryptogenic organizing pneumonia, desquamative interstitial pneumonia, pleuropulmonary metastases, and/or bronchopulmonary infection, but the histological and immunohistochemical results were compatible with pleural mesothelioma - a rare malignant neoplasm, with pleural origin, with a high mortality rate.

Dosimetry of Occupational Radiation around Panoramic X-ray Apparatus

Background:

Panoramic imaging is one of the most common imaging methods in dentistry. Regarding the side-effects of ionizing radiation, it is necessary to survey different aspects and details of panoramic imaging. In this study, we compared the absorbed x-ray dose around two panoramic x-ray units: PM 2002 CC Proline (Planmeca, Helsinki, Finland) and Cranex Tome (Soredex, Helsinki, Finland).

Materials and Methods:

In this cross-sectional study, 15 thermoluminescet dosemeters (TLD-100) were placed in 3 semi-circles of 40cm, 80cm and 120cm radii in order to estimate x-ray dose. Around each unit, the number of TLDs in each semi-circle was 5 with equal intervals. The center of semicircles accords with the patient’s position. Each TLD was exposed 40 times. These dosemeters were read out with a Harshaw Model 4000 TLD Reader (USA). The calibration processing and the reading of dosemeters were performed by the Atomic Energy Organization of Iran.

Results:

The mean absorbed dose in three lines of PM 2002 CC Proline was 123.2±15.1, 118.0±11.0 and 108.0±9.1 µSv, (p=0.013). The results were 140.4±15.2, 120.2±10.4 and 111.6±11.2 µSv in Cranex Tome (p=0.208), which reveals no significant difference between two systems.

Conclusion:

There are no significant differences between the mean absorbed dose of surveyed models in panoramic imaging by two units (PM 2002 CC Proline and Cranex Tome). These results were less than occupational exposure recommended by ICRP, even at the highest calculated doses.

Feasibility study for interspecialistic collaboration in active research of urothelial neoplasms of professional origin

INTRODUCTION

In Italy only a small fraction of cancer is reported to the supervisory body and recognised as professional by the insurance institution. Among the causes of this sub-notification, especially for lowgrade etiologic fractional cancers such as bladder cancers are the lack of knowledge of carcinogenicity in the occupational field and the consequent incomplete medical history collections.

OBJECTIVES

Diagnosis of occupational bladder neoplasms and activation of systematic surveillance of tumors of professional origin through an "active research" program.

METHODS

From July 2010 to July 2017, all patients diagnosed with Bladder Cancer in the departments of Urology of Area Vasta 3 ASUR Marche underwent a first interview and a further anamnestic study in selected cases.When an occupational exposure was recognised, more information for preventive, social security and criminal justice has been acquired.

RESULTS

The study highlighted 18 cases of bladder tumors due to occupational exposure to aromatic amines and polycyclic aromatic hydrocarbons, which are the most important risk factor for BC after tobacco smoking.

CONCLUSIONS

Our study confirmed that active research is an useful tool both for the activation of epidemiological surveillance and for the regional registration of professional tumors. In addition active research of occupational exposure allow obtaining information that can be used for preventive purposes, for criminal justice and for the initiation of medico-legal actions and improvement of working conditions aimed at guaranteeing workers' rights.

Implementation of Hospital Policy for Healthcare Workers and Patients Exposed to Varicella-Zoster Virus

Varicella-zoster virus (VZV) causes a highly contagious and generally benign, self-limited disease. However, in high-risk populations including immunocompromised patients, pregnant women, and neonates, VZV infection can be associated with significant morbidity and mortality. Healthcare-associated transmission of VZV occurs among healthcare workers (HCWs) and patients by airborne transmission or by direct contact with the index case. To minimize the risk of transmission in healthcare settings, all VZV-susceptible HCWs should be encouraged strongly to be immunized with the varicella vaccine. For post-exposure management, active immunization (varicella vaccine), passive immunization (varicella-zoster immune globulin) and/or antiviral agents, and isolation could be used in specific situations. To prevent the transmission of VZV infection in the hospital settings, the development and implementation of hospital policies for appropriate infection control is also warranted. This article reviews the general information and healthcare-associated transmission of VZV and summarizes the recommendations for the pre- and post-exposure management of HCWs and patients, in hospital settings.

Exposure to airborne endotoxin in Italian greenhouses: environmental analyses

The peculiar characteristics of the greenhouses as confined spaces, microclimate and poor air exchange with the outside environment, encourage the development of a large number of biological agents. Endotoxin, is probably a major causative agent of occupational health problems. The objective of this study was to measure the concentrations of airborne endotoxin in greenhouses with different cultures. The influence of microclimate was studied in correlation with endotoxin levels and type of cultured vegetables. The data indicate that workers employed greenhouses are exposed to low levels of inhalable endotoxins; endotoxin concentrations do not correlate with the temperature and relative humidity values. A strong correlation between the leaf size and endotoxin concentration was observed. The mean concentration of endotoxins in the air of greenhouses is relatively low, however, there could be peaks of exposure during harvesting and eradication of broadleaf plants.

Occupational Risk of Latent Tuberculosis Infection in Health Workers of 14 Military Hospitals

Tuberculosis (TB) is a known occupational risk to health workers. Identifying risk factors in health care settings is critical to the prevention of TB for health workers and patients. In 2014, we carried out a TB screening and survey for 902 health workers from 14 selected military hospitals to determine the prevalence rate of latent tuberculosis infection (LTBI) as well as occupational risk factors. Of all subjects, 19.5% reported having provided TB patient care for 1 year or more (176/902), and 26.9% (243/902) were positive for the tuberculin skin test (TST) (10 mm or more of induration). Additionally, 21.4% (52/243) of those who tested positive were also positive for the interferon-gamma release assay (IGRA). The proportion of LTBI in the study population was 5.8% (52/902). In a multivariate logistic regression analysis, providing TB patient care for one year or more was the only significant occupational risk factor (adjusted odds ratio [aOR], 2.27; 95% confidence interval [CI], 1.13-4.56). This study suggests that military health workers working with TB patients should be regularly examined by chest radiography, TST and IGRA to detect LTBI in the early stage and control nosocomial infection of TB.

[Characteristics of communication systems of suspected occupational disease in the Autonomous Communities, Spain]

BACKGROUND

There are several initiatives to develop systems for the notification of suspected occupational disease (OD) in different autonomous communities. The objective was to describe the status of development and characteristics of these systems implemented by the health authorities.

METHODS

A cross-sectional descriptive study was carried out on the existence of systems for the information and surveillance of suspected OD, their legal framework, responsible institution and availability of information. A specific meeting was held and a survey was designed and sent to all autonomous communities and autonomous cities (AACC). Information was collected on the existence of a regulatory standard, assigned human resources, notifiers, coverage and number of suspected OD received, processed and recognized.

RESULTS

18 of 19 AACC responded. 10 have developed a suspected OD notification system, 3 of them supported by specific autonomic law. The notifiers were physicians of the public health services, physicians of the occupational health services and, in 2 cases, medical inspectors. 7 AACC had specific software to support the system. The OD recognition rate of suspected cases was 53% in the Basque Country; 41% in Castilla-La Mancha; 36% in Murcia; 32.6% in the Valencian Community and 31% in La Rioja.

CONCLUSIONS

The study has revealed an heterogeneous development of suspected OD reporting systems in Spain. Although the trend is positive, only 55% of the AACC have some type of development and 39% have specific software supporting it. Therefore unequal OD recognition rates have been obtained depending on the territory.

[Differences in the recognition of occupational diseases by sex, occupation and business activity in Spain (1990-2009)]

BACKGROUND

According to official statistics, men suffer more occupational diseases (OD) than women. Nevertheless, the unequal distribution and participation in the labor markets between men and women should be kept in mind. The purpose was to assess the gender impact in the recognition of OD in Spain, examining interaction and confounding factors.

METHODS

An incidence study of the occupational diseases declared through the official OD reporting forms from 1999 to 2009, provided by the General Subdirectorate of Social and Labor Statistics of the Ministry of Employment and Social Security, was conducted. The variables included were: reporting year, sex, age, occupation and economic activity of the company. Rates and crude relative risks (cRR) by these variables were calculated. Adjusted RR were also computed by using multivariate Poisson regression.

RESULTS

During the study period a total of 243,310 OD were reported in Spain, with a sex ratio of men to women of 1.07. Correlation existed between occupation and business activity, thus the OD rates and RR were computed by these variables separately. By occupation, men had a crude RR of 1.067 (95%CI:1.058 to 1.076) versus women, while wen the analysis was adjusted by all the variables, the RR was 0.507 (95%CI:0.502 to 0.512). By economic activity of the company, the sense of risk was reversed too in the adjusted analysis (cRR=1.065, 95%CI:1.056 to 1.074 versus 0.632, 95%CI:0.626 to 0.638).

CONCLUSIONS

Although crude OD rates were lower in women than in men during the period 1999-2009 in Spain, when these rates were adjusted by company activity or worker occupation, age and year of OD declaration, RRs become almost 50% higher in women than in men for the majority of occupations and types of company activity.

The Effect of Wood Aerosols and Bioaerosols on the Respiratory Systems of Wood Manufacturing Industry Workers in Golestan Province

BACKGROUND

Occupational exposure to dust leads to acute and chronic respiratory diseases, occupational asthma, and depressed lung function. In the light of a lack of comprehensive studies on the exposure of Iranian workers to wood dusts, the objective of this study was to monitor the occupational exposure to wood dust and bioaerosol, and their correlation with the lung function parameters in chipboard manufacturing industry workers.

MATERIALS AND METHODS

A cross-sectional study was conducted on chipboard workers in Golestan Province; a total of 150 men (100 exposed cases and 50 controls) were assessed. Workers were monitored for inhalable wood dust and lung function parameters, i.e., FVC, FEV1, FEV1/FVC, and FEF25-75%. The workers' exposure to bioaerosols was measured using a bacterial sampler; a total of 68 area samples were collected. The analysis was performed using the Mann-Whitney, Kruskal-Wallis, and regression statistical tests.

RESULTS

The geometric mean value and geometric standard deviation of inhalable wood dust for the exposed and control groups were 19 ± 2.00 mg/m3 and 0.008 ± 0.001 mg/m3, respectively. A statistically significant correlation was observed between the lung parameters and cumulative exposure to inhalable wood dust, whereas a statistically significant correlation was not observed between the lung parameters and bioaerosol exposure. However, the exposure of Iranian workers to bioaerosols was higher, compared to their foreign coworkers.

CONCLUSION

Considering the high level of exposure among workers in this study along with their lung function results, long-term exposure to wood dust may be detrimental to the workers' health and steps to limit their exposure should be considered seriously.

Facing Complaining Customer and Suppressed Emotion at Worksite Related to Sleep Disturbance in Korea

This study aimed to investigate the effect of facing complaining customer and suppressed emotion at worksite on sleep disturbance among working population. We enrolled 13,066 paid workers (male = 6,839, female = 6,227, age < 65 years) in the 3rd Korean Working Condition Survey (2011). The odds ratio (OR) and 95% confidence intervals (CI) for sleep disturbance occurrence were calculated using multiple logistic regression models. Among workers in working environments where they always engage complaining customers had a significantly higher risk for sleep disturbance than rarely group (The OR [95% CI]; 5.46 [3.43-8.68] in male, 5.59 [3.30-9.46] in female workers). The OR (95% CI) for sleep disturbance was 1.78 (1.16-2.73) and 1.63 (1.02-2.63), for the male and female groups always suppressing their emotions at the workplace compared with those rarely group. Compared to those who both rarely engaged complaining customers and rarely suppressed their emotions at work, the OR (CI) for sleep disturbance was 9.66 (4.34-20.80) and 10.17 (4.46-22.07), for men and women always exposed to both factors. Sleep disturbance was affected by interactions of both emotional demands (engaging complaining customers and suppressing emotions at the workplace). The level of emotional demand, including engaging complaining customers and suppressing emotions at the workplace is significantly associated with sleep disturbance among Korean working population.

Occupational Exposure and Health Impairments of Formaldehyde on Employees of a Wood Industry

Background: Occupational exposure to formaldehyde may decrease white blood cell counts and change blood concentration. In this study, the influences of occupational exposure to formaldehyde on the number of white blood cells and blood concentrations were studied.

Methods: This case-control study was conducted in June of 2012 at North Wood Factory, Golestan Province, Iran. The US-NIOSH method No. 2541 was used to determine the occupational exposure of 30 workers of the production line (case group) and 30 administrative staffs (control group) to formalde­hyde. The number of white blood cells and blood concentration were determined using the normal blood count method and related indices. Demographic features as well as the symptoms of being exposed to formaldehyde were collected using a standard questionnaire.

Results: The occupational exposure of case group ranged from 0.50 ppm to 1.52 ppm. The prevalence of all studied symptoms from formaldehyde exposure in workers (2<median<5; range 1 to 5) was signifi­cantly different (P<0.001) towards the administrative staffs (median 1; range 1 to 4). The number of white blood cells in production line workers was not significantly different from those in administra­tive staff. The average blood concentration in the case group was significantly different from the con­trol group (mean difference= 0.9 [95% CI: 0.40-1.39];P=0.007).

Conclusion: Occupational exposure to formaldehyde changed the blood concentration of the studied workers but did not change the number of their white blood cells.

Short-term metal particulate exposures decrease cardiac acceleration and deceleration capacities in welders: a repeated-measures panel study

OBJECTIVE

Acceleration (AC) and deceleration (DC) capacities measure heart rate variability during speeding up and slowing down of the heart, respectively. We investigated associations between AC and DC with occupational short-term metal PM2.5 exposures.

METHODS

A panel of 48 male welders had particulate matter less than 2.5 microns in diameter (PM2.5) exposure measurements over 4-6 h repeated over 5 sampling periods between January 2010 and June 2012. We simultaneously obtained continuous recordings of digital ECG using a Holter monitor. We analysed ECG data in the time domain to obtain hourly AC and DC. Linear mixed models were used to assess the associations between hourly PM2.5 exposure and each of hourly AC and DC, controlling for age, smoking status, active smoking, exposure to secondhand smoke, season/time of day when ECG reading was obtained and baseline AC or DC. We also ran lagged exposure response models for each successive hour up to 3 h after onset of exposure.

RESULTS

Mean (SD) shift PM2.5 exposure during welding was 0.47 (0.43) mg/m(3). Significant exposure-response associations were found for AC and DC with increased PM2.5 exposure. In our adjusted models without any lag between exposure and response, a 1 mg/m(3) increase of PM2.5 was associated with a decrease of 1.46 (95% CI 1.00 to 1.92) ms in AC and a decrease of 1.00 (95% CI 0.53 to 1.46) ms in DC. The effect of PM2.5 on AC and DC was maximal immediately postexposure and lasted 1 h following exposure.

CONCLUSIONS

There are short-term effects of metal particulates on AC and DC.

Does Occupational Exposure of Shahid Dastghieb International Airport Workers to Radiofrequency Radiation Affect Their Short Term Memory and Reaction Time?

BACKGROUND

Airport workers are continuously exposed to different levels of radiofrequency microwave (RF/MW) radiation emitted by radar equipments. Radars are extensively used in military and aviation industries. Over the past several years, our lab has focused on the health effects of exposure to different sources of electromagnetic fields such as cellular phones, mobile base stations, mobile phone jammers, laptop computers, radars, dentistry cavitrons and MRI. The main goal of this study was to investigate if occupational exposure of Shahid Dastghieb international airport workers to radiofrequency radiation affects their short term memory and reaction time.

METHODS

Thirty two airport workers involved in duties at control and approach tower (21 males and 11 females), with the age range of 27-67 years old (mean age of 37.38), participated voluntary in this study. On the other hand, 29 workers (13 males, and 16 females) whose offices were in the city with no exposure history to radar systems were also participated in this study as the control group. The employees' reaction time and short term memory were analyzed using a standard visual reaction time (VRT) test software and the modified Wechsler memory scale test, respectively.

RESULTS

The mean± SD values for the reaction times of the airport employees (N=32) and the control group (N=29) were 0.45±0.12 sec and 0.46±0.17 sec, respectively.  Moreover, in the four subset tests; i.e. paired words, forward digit span, backward digit span and word recognition, the following points were obtained for the airport employees and the control group, respectively: (i) pair words test: 28.00±13.13 and 32.07±11.65, (ii) forward digit span: 8.38±1.40 and 9.03±1.32, (iii) backward digit span: 5.54±1.87 and 6.31±1.46, and (iv) word recognition: 5.73±2.36 and 6.50±1.93. These differences were not statistically significant.

CONCLUSION

The occupational exposure of the employees to the RF radiation in Shahid Dastghieb international airport does not have any significant detrimental effect on their reaction time as well as short term memory.

Occupational Exposure of Shiraz Dental Students to Patients' Blood and Body Fluid

STATEMENT OF THE PROBLEM

Exposure to patients' blood and body fluids would prone the dental students to the risk of blood borne infections. Several studies have shown a high prevalence of these exposures in dental settings particularly in developing countries. However, few studies have evaluated the epidemiology of these exposures in dental students in Iran.

PURPOSE

To assess the epidemiology of occupational exposures among dental students and consequently designing the appropriate interventions in order to prevent these exposures.

MATERIALS AND METHOD

In this cross-sectional study performed during March to June 2011, all 191 Shiraz clinical dental students were asked to complete a self-administered questionnaire. This questionnaire included demographic information and experience of sharp injuries and mucocutaneous contaminations. Chi square and t-test were employed to evaluate the risk factors of exposure.

RESULTS

80%of the participants were exposed to the patients' blood or body fluids during their clinical course. No association was found between the exposure and demographic factors. Injection needle and recapping were the most common causes of these injuries. The most common sites that were injured and caused mucocutaneous contamination were finger and face, respectively. The most frequent activity causing contamination was using high-speed rotary instruments. Only 6.4% of the exposures had been reported to the related authorities and the remains were underreported.

CONCLUSION

Blood and body fluid exposure in dental setting is common and a lot of them are not reported. To reduce the hazards of these exposures, infection control authorities should design interventions especially for mentioned high-risk conditions. They should change dental students' behavior especially regarding not recapping injection needles and using eyewear. Dental schools seem to need a management center and a standard protocol for following up the exposures.

Evaluation of Genomic Damage in Peripheral Lymphocytes from Occupationally Exposed Anesthetists: Assessment of the Effects of Age, Sex, and GSTT1 Gene Polymorphism

Occupational exposure to anaesthetic gases is one of the major hazards to healthcare personnel. We evaluated the cytogenetic effects of chronic exposure to low concentrations of anaesthetic gases in operating theatres. The study included 21 anesthetists and 21 control subjects who matched in age and gender. Chromosome aberrations (CAs) and sister chromatid exchanges (SCEs) assays were performed. All subjects were also genotyped for glutathione S-transferase T1 (GSTT1) gene polymorphisms. Significant differences were found between exposed and controls in terms of SCEs frequency (P = 0.001) and replication index value (P = 0.005), but not in terms of CAs (P = 0.201) and aberrant cells (P = 0.227) frequencies. Regression analyses indicated that age and the years of employment did not influence the level of chromosomal damage in both groups. Finally, among anesthetists, GSTT1 null individuals showed a significant higher frequency of SCE with respect to GSTT1-positive subjects.

Effect of Ventilation on Occupational Exposure to Airborne Biological Contaminants in an Isolation Room

BACKGROUND

Airborne pathogens play an important role in a hospital air quality. Respiratory infections are the most common occupational disease among the health care staff. The aim of this study was to determine the effect of ventilation system parameters and patient bed arrangements on concentration of airborne pathogens in indoor air of an isolation room.

MATERIALS AND METHODS

A single-bed room was considered in which a patient diagnosed with tuberculosis had been admitted. Five different ventilation types, each at four different capacities were installed in the room while two different locations for the patient's bed were assessed. A direct-impact sampling method (blood agar plate) was used in order to determine the intensity of the bio-aerosols in indoor air of the isolation room.

RESULTS

The results showed that when the air was supplied through a circular vent located on the northern wall and the vented air was exhausted via a linear vent located on the southern wall, the average concentration of the bio-aerosols in the air, (with 12 air changes per hour) was reduced to 25 colonies per cubic meter (cfu/m(3)) (in the range of 25-88 cfu/m(3) and a 95 percent confidence interval). In accordance with the analysis applied upon the two different locations of the bed, no significant difference was observed (P>0.05).

CONCLUSION

Installation of ventilation systems as determined by the study is recommended for tuberculosis isolation rooms.

Occupational asthma in a cable manufacturing company

Background:

During the past decade, incidence of asthma has increased, which might have been due to environmental exposures.

Objectives:

Considering the expansion of cable manufacturing industry in Iran, the present study was conducted to evaluate the prevalence of occupational asthma in a cable manufacturing company in Iran as well as its related factors.

Patients and Methods:

This study was conducted on employees of a cable manufacturing company in Yazd, Iran, in 2012. The workers were divided into two groups of exposure (to toluene diisocyanate, polyvinyl chloride, polyethylene or polypropylene) and without exposure. Diagnosis of occupational asthma was made based on the subjects’ medical history, spirometry and peak flowmetry, and its frequency was compared between the two groups.

Results:

The overall prevalence of occupational asthma was 9.7%. This rate was 13.8% in the exposed group. Logistic regression analysis showed that even after adjustment for confounding factors, a significant correlation existed between the frequency of occupational asthma and exposure to the produced dust particles (P < 0.05). In addition, age, work experience, body mass index, cigarette smoking and shift work had significant correlations with the prevalence of occupational asthma (P < 0.05).

Conclusions:

Considering the high prevalence of occupational asthma among cable manufacturing company workers in Iran, this issue needs to be addressed immediately in addition to reduction of exposure among subjects. Reduction in work shift duration, implementation of tobacco control and cessation programs for the personnel, and performing spirometry tests and respiratory examinations in shorter periods may be among effective measures for reducing the incidence of occupational asthma in this industry.

Influence of environmental exposures on patients with chronic obstructive pulmonary disease in Korea

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation and results from environmental factors and genetic factors. Although cigarette smoking is a major risk factor, other environmental exposures can influence COPD. The purpose of this study is to investigate the clinical characteristics of COPD according to the history of environmental exposure.

METHODS

The study population comprised of 347 subjects with COPD who were recruited from the pulmonary clinics of 14 hospitals within the Korean Obstructive Lung Disease Study Group. We classified environmental exposures according to history of living near factory, and direct exposure history to firewood or briquette. According to living environmental exposures, we compared the frequency of respiratory symptoms, pulmonary function, quality of life, exercise capacity, and computed tomography phenotypes.

RESULTS

Thirty-one subjects (8.9%) had history of living near factory, 271 (78.3%) had exposure history to briquette, and 184 (53.3%) had exposure history to firewood. Patients with history of living near a factory had a significantly longer duration of sputum, while patients with exposure to firewood tended to have lower forced expiratory volume in one second, and patients with exposure to briquette tended to have lower six minute walk distance.

CONCLUSION

COPD subjects with the history of living near factory had more frequent respiratory symptoms such as sputum. Our data suggest that environmental exposure may influence clinical phenotype of COPD.

A case of occupational hypersensitivity pneumonitis associated with trichloroethylene

Trichloroethylene (TCE) is a toxic chemical commonly used as a degreasing agent, and it is usually found in a colorless or blue liquid form. TCE has a sweet, chloroform-like odor, and this volatile chlorinated organic chemical can cause toxic hepatitis, neurophysiological disorders, skin disorders, and hypersensitivity syndromes. However, the hypersensitivity pneumonitis (HP) attributed to TCE has rarely been reported. We hereby describe a case of HP associated with TCE in a 29-year-old man who was employed as a lead welder at a computer repair center. He was installing the capacitors on computer chip boards and had been wiped down with TCE. He was admitted to our hospital with complaints of dry coughs, night sweats, and weight losses for the past two months. HP due to TCE exposure was being suspected due to his occupational history, and the results of a video-associated thoracoscopic biopsy confirmed the suspicions. Symptoms have resolved after the steroid pulse therapy and his occupational change. TCE should be taken into consideration as a potential trigger of HP. Early recognition and avoidance of the TCE exposure in the future is important for the treatment of TCE induced HP.

Severe Cognitive Dysfunction and Occupational Extremely Low Frequency Magnetic Field Exposure among Elderly Mexican Americans

Aims

This report is the first study of the possible relationship between extremely low frequency (50–60 Hz, ELF) magnetic field (MF) exposure and severe cognitive dysfunction. Earlier studies investigated the relationships between MF occupational exposure and Alzheimer’s disease (AD) or dementia. These studies had mixed results, depending upon whether the diagnosis of AD or dementia was performed by experts and upon the methodology used to classify MF exposure.

Study Design

Population-based case-control.

Place and Duration of Study

Neurology and Preventive Medicine, Keck School of Medicine, University of Southern California, 2 years.

Methodology

The study population consisted of 3050 Mexican Americans, aged 65+, enrolled in Phase 1 of the Hispanic Established Population for the Epidemiologic Study of the Elderly (H-EPESE) study. Mini-Mental State Exam (MMSE) results, primary occupational history, and other data were collected. Severe cognitive dysfunction was defined as an MMSE score below 10. The MF exposure methodology developed and used in earlier studies was used.

Results

Univariate odds ratios (OR) were 3.4 (P< .03; 95% CI: 1.3–8.9) for high and 1.7 (P=.27; 95% CI: 0.7–4.1) for medium or high (M/H) MF occupations. In multivariate main effects models, the results were similar. When interaction terms were allowed in the models, the interactions between M/H or high occupational MF exposure and smoking history or age group were statistically significant, depending upon whether two (65–74, 75+) or three (65–74, 75–84, 85+) age groups were considered, respectively. When the analyses were limited to subjects aged 75+, the interactions between M/H or high MF occupations and a positive smoking history were statistically significant.

Conclusion

The results of this study indicate that working in an occupation with high or M/H MF exposure may increase the risk of severe cognitive dysfunction. Smoking and older age may increase the deleterious effect of MF exposure.

Risk of hepatocellular carcinoma in workers exposed to chemicals

CONTEXT

Studies on experimental animals have shown liver is a common target of chemical carcinogens; this might suggest that occupational exposure to chemicals is another risk factor for HCC. However, the relationship between occupation and liver cancer has not been extensively studied, with the exception of the known association between vinyl chloride and angiosarcoma of the liver.

EVIDENCE ACQUISITION

A MEDLINE and conventional search of the past 50 years of the medical literature was performed to identify relevant articles on incidence and mechanisms of HCC due to occupational exposure to chemicals. Several important edited books and monographs were also identified and reviewed.

RESULTS

While laboratory data clearly indicate that the liver is an important target of chemical carcinogenesis, epidemiological studies provide very limited evidence on occupational risk factors for HCC. Nevertheless, we found some case reports and epidemiological data showing a moderately increased risk of HCC development in people exposed to vinyl chloride, organic solvents, pesticides, polychlorinated biphenyls, and arsenic.

CONCLUSIONS

Occupational exposure to chemicals may be another risk factor for HCC development, but the interpretation of currently available findings is limited by the small number of studies, questionable accuracy of the diagnosis of liver cancer, and potential confounding or modifying factors such as chronic hepatitis virus infection and alcohol consumption. Further relevant investigations are required for clarifying the actual contribution of occupational exposure to chemicals in HCC development.

The relationship between occupational radiation exposure and thyroid nodules

BACKGROUND

Considering that thyroid nodules and thyroid cancer occur more frequently in people chronically exposed to radiation, the aim of this study was to evaluate the prevalence of thyroid nodules in a population occupationally exposed to radiation in hospitals of Isfahan, Iran.

MATERIALS AND METHODS

In this case-control study, the prevalence of thyroid nodules in staff members occupationally exposed to radiation was determined by ultrasonography. The results were compared with the results of another study among the adult population of Isfahan which selected by cluster random sampling method. The 2 studied groups were matched according to sex and age.

RESULTS

The case and control groups included 124 and 471 persons, respectively. The prevalence of thyroid nodules in the case and control groups was 22.6% and 24.6%, respectively (p > 0.05). Although thyroid nodules were significantly more prevalent in females in the control group, no such difference was observed between females and males of the case group (p > 0.05). The number of thyroid nodules (single or multiple) and calcification were not different between the two groups (p > 0.05). In addition, hypoechogenicity of thyroid nodules was not different between the two groups for (p > 0.05).

CONCLUSION

In our study, there was not any correlation between chronic occupational exposure to low dose of radiation and the risk of developing thyroid nodules. Further studies with larger sample sizes, at different doses of radiation, and considering iodine status and thyroid function are thus required.

Effect of the amount of battery charge on tube voltage in different hand-held dental x-ray systems

Purpose

Hand-held dental x-ray system is a self contained x-ray machine designed to perform intraoral radiography with one or two hands. The issue about its usage as general dental radiography is still in dispute. The aim of the present study was to assess the relationship between the amount of battery charge and the tube voltage in different hand-held dental x-ray systems.

Materials and Methods

Seven hand-held dental x-ray units were used for the study. Tube voltage was measured with Unfors ThinX RAD (Unfors Instruments AB, Billdal, Sweden) for 3 consecutive exposures at the different amount of battery charge of each unit. The average and the deviation percentage of measured kV from indicated kV of each unit were calculated.

Results

Tube voltage of only 1 unit was 70 kV (indicated by manufacturer) and those of the others were 60 kV. Tube voltage deviation percentage from the indicated kV at the fully charged battery was from 2.5% to -5.5% and from -0.8% to -10.0% at the lowest charged battery.

Conclusion

Tube voltages of all units decreased as the residual amount of the battery charge decreased. It is suggested that the performance test for hand-held x-ray system should be performed for the minimum residual charged battery as well as the full charged one. Persistent battery charging is suggested to maintain the proper tube voltage of the hand-held portable x-ray system.

Effects of occupational exposure to lead on left ventricular echocardio graphic variables

BACKGROUND

Lead contamination can affect many body organs including the heart. This study assessed a number of echocardiographic indices to clarify the effects of lead on cardiac function among battery factory workers who are in constant exposure to lead.

METHODS

In a cross-sectional study, 142 male battery factory workers who had been exposed to lead for at least 1 year were evaluated. The subjects aged 25-55 years old and were excluded if they had hypertension, diabetes, or cardiovascular diseases. Demographic characteristics, professional profile, lead exposure, history of respiratory diseases, drugs intake, and lifestyle information of the participants were collected. Height, weight and blood pressure measurements were then performed. Blood tests were also ordered to determine blood lead levels. The subjects finally underwent M-mode and Doppler echocardiography. Linear regression analysis was used to establish the effects of lead on the target indices. All statistical analyses were conducted in SPSS18.

RESULTS

The mean age and mean duration of lead exposure of the subjects were 41.78 ± 13.58 and 23.54 ± 14.44 years, respectively. The mean blood lead level was 7.59 ± 2.75 µg/dl. Left ventricular hypertrophy was detected in 12% of the participants. Blood lead levels were not significantly related with echocardiographic indices in the crude model or after adjustments for age alone or for age and other risk factors.

CONCLUSION

Blood lead levels of our participants were below standard values. In addition, no significant relation was found between left ventricular function indices and blood lead levels. The absence of such relations could have been caused by the exclusion of individuals with hypertension or cardiovascular diseases. Structural modifications in battery factories following legislations in Iran might have been responsible for low blood lead levels among the subjects.

The Relationship between Occupation and Semen Quality

BACKGROUND

Infertility can be a major concern for couples trying to conceive, and occupational hazards may constitute a main cause of infertility in men. Studies conducted throughout the world indicate that physical and chemical hazards in the workplace can have a negative impact on male fertility. The main objective of this study was to determine the frequency of occupational categories of men who attended an infertility clinic, and to evaluate the differences in the semen quality parameters among occupational categories.

MATERIALS AND METHODS

This cross-sectional study was conducted on 1164 males who were referred to the Infertility Research Center in Tehran for treatment of infertility in order to evaluate the effects of certain occupations on infertility. The participants were divided into several categories according to their occupations and evaluated by means of a questionnaire for duration of infertility, BMI, sperm count, percentage of normal sperm morphology and percentages of sperm with class A and class B motilities. Descriptive statistics, analysis of variance, and correlations were conducted using SPSS 16.0 for Windows.

RESULTS

There were no statistically significant differences in the mean sperm count or sperm morphology between occupational categories. Assessment of the differences in the frequency of sperm motility classes between occupational categories revealed a significant difference only in the frequency of sperm with class B motility. The lowest mean percentages of sperm with class B motility were seen in those involved in the transportation industry, a finding in agreement with a number of other researches.

CONCLUSION

Our findings revealed an association between occupation and sperm motility. Since our study population was relatively small and in many cases exposures to work hazards were brief, a larger study group must be evaluated in order to support the preliminary results of this study.

Ionizing radiation-induced diseases in Korea

Radiation risk has become well known through epidemiological studies of clinically or occupationally exposed populations, animal experiments, and in vitro studies; however, the study of radiation related or induced disease has been limited in Korea. This study is to find the level of occupational radiation exposure for various kinds of accidents, compensated occupational diseases, related studies, and estimations on future occupational disease risks. Research data of related institutions were additionally investigated. About 67% of 62,553 radiation workers had no exposure or less than 1.2 mSv per year. The 5 reported cases on radiation accident patients in Korea occurred during nondestructive testing. According to the recent rapid increase in the number of workers exposed to radiation, a higher social recognition of cancer, and an increasing cancer mortality rate, it is expected that occupational disease compensation will rapidly increase as well. Therefore, it is important to develop scientific and objective decision methods, such as probability of causation and screening dose in the establishment of an exposure and health surveillance system.