An agent-based model to simulate SARS-CoV-2 contamination of surfaces and meat cuts in processing plants

At the beginning of the COVID-19 pandemic, several contamination clusters were reported in food-processing plants in France and several countries worldwide. Therefore, a need arose to better understand viral transmission in such occupational environments from multiple perspectives: the protection of workers in hotspots of viral circulation; the prevention of supply disruption due to the closure of plants; and the prevention of cluster expansion due to exports of food products contaminated by the virus to other locations. This paper outlines a simulation-based approach (using agent-based models) to study the effects of measures taken to prevent the contamination of workers, surfaces, and food products. The model includes user-defined parameters to integrate characteristics relating to SARS-CoV-2 (variant of concern to be considered, symptom onset…), food-processing plants (dimensions, ventilation…), and other sociodemographic transmission factors based on laboratory experiments as well as industrial and epidemiological investigations. Simulations were performed for a typical meat-processing plant in different scenarios for illustration purposes. The results suggested that increasing the mask-wearing ratio led to great reductions in the probability of observing clusters of more than 25 infections. In the case of clusters, masks being worn by all workers limited the presence of contamination (defined as levels of at least 5 log10 viral RNA copies) on meat cuts at less than 0.05 % and maintained the production capacity of the plant at optimal levels. Increasing the average distance between two workers from less than 1 m to more than 2 m decreased the cluster-occurrence probability by up to 15 % as well as contamination of food products during cluster situations. The developed approach can open up several perspectives in terms of potential communication-support tools for the agri-food sector and further reuses or adaptations for other hazards and occupational environments.

Dysregulation of butyrylcholinesterase, BCHE gene SNP rs1803274, and pro-inflammatory cytokines in occupational workers

BACKGROUND

People in different occupations are exposed to a variety of xenobiotics which affect the health and physiological processes of the body. Butyrylcholinesterase (BChE), has been reported to play neuronal and non-neuronal roles, though its exact function is yet to be established. This study aimed to find the status and role of BChE in seven different occupational groups; gasoline fillers, auto-mechanics, carpenters, textile shop workers, furniture shop workers, electricians, and office workers.

METHODS

A total of 400 samples were screened. BChE activity was determined by Worek et al. method based on Ellman's principle. Pro-inflammatory cytokines were determined by ELISA. Genotypic analysis of the K-variant of BCHE gene SNP was carried out by standard molecular methods. Among seven groups, office workers were taken as a control to compare the results with all other occupational groups.

RESULTS

The results revealed a significant decrease in BChE activity in gasoline fillers (79.52%) followed by carpenters (73.49%), auto mechanics (39.76%), textile shop workers (18.07%), electricians (10.84%), and furniture shop workers (7.23%). TNF-α, IL-6, and IL1-β were elevated in all groups. IL-6 and IL1-β in gasoline fillers, and electricians were not statistically significantly increased. Binomial regression to determine the odd ratio was found to be significant (p < 0.05) in all groups. However, correlation (Pearson) did not reveal significance between different biochemical parameters. Genotypic analysis of the K-variant SNP of the BCHE gene showed a significant association with occupational groups when compared with control which indicates a possible association with xenobiotics exposure and the physiological role of K-variant in understudied occupational groups.

CONCLUSION

The study concluded that BChE and its gene SNP rs 1803274 and proinflammatory cytokines significantly dysregulates under the exposure to cumulative multiple xenobiotics in different occupational groups which may lead to pathophysiological conditions.

[The method of determination for sulfur dioxide in the air of workplace by ion chromatography without derivatization]

Objective: To establish a method for the determination of sulfur dioxide (SO₂) in the air of workplace, which including the process of collection by absorption in triethanolamine aqueous solution and the process of analysis and detection by iron chromatography directly without derivatization. Methods: SO₂ in the air of workplace was collected at a flow rate of 0.5 L/min for 15 min through 10 ml of 3% triethanolamine aqueous solution filled in a porous glass plate absorption tube. The absorption solution passed through IonPacAS14A analytical column (4 mm×250 mm) and IonPacAG14 protective column (4 mm×50 mm) at a column temperature of 30 ℃, using Na₂CO₃ (3.0 mmol/L) -NaHCO₃ (1.0 mmol/L) as mobile phase with the flow rate of 1.2 ml/min, and was detected by conductivity detector. Results: It showed that SO₂ in triethanolamine solution could be stored for at least 7 d at room temperature (25 ℃) and 37 ℃. There was a linear relationship within the determination range of 0-8.00 μg/ml, the linear correlation coefficient was 0.9999. The sampling absorption efficiency was 98.1%-100.0%, the detection limit of the method was 0.018 μg/ml, the minimum detection concentration was 0.024 mg/m³ (based on V₀=7.5 L) . The recovery rate was 99.22%-101.69%, the intra batch precision was 0.41%-1.34%, and the inter batch precision was 0.73%-1.77%. Conclusion: The method has the advantages of simple operation, high sensitivity and good accuracy. It can prevent SO₂ from being oxidized and realize the direct detection of SO₂ in the air of workplace without derivation.

[Current status of depression among workers in a petrochemical enterprise in Liaoning Province, China and related influencing factors]

Objective: To investigate the influencing factors for depression among workers in a petrochemical enterprise and the association of occupational stress and occupational environment with depression, and to provide a scientific basis for the improvement of mental health and the prevention and treatment of depression among workers in petrochemical enterprises. Methods: A cross-sectional study was performed in March 2018, and cluster sampling was used to select 1888 workers from a petrochemical enterprise in Liaoning Province, China for a questionnaire survey. A total of 1888 questionnaires were collected, among which there were 1521 usable questionnaires, with an effective recovery rate of 80.56%. The general status of the workers in this petrochemical enterprise was investigated, and Center for Epidemiologic Studies Depression Scale (CES-D) , Effort-Reward Imbalance (ERI) , and Perceived Work Environment (PWE) were used to evaluate depression, occupational stress, and occupational environment. Constituent ratio was used to describe the distribution of different demographic features, work conditions, and lifestyles among the workers in this petrochemical enterprise. One-way analysis of variance and the t-test were used to compare the scores of depressive tendency between the workers with different features. Pearson correlation analysis was used to investigate the correlation of occupational stress and occupational environment with depression. Multivariate hierarchical regression analysis was used to investigate the influencing factors for depression. Results: The score of depression tendency was 18.94±9.21 in the workers in this petrochemical enterprise, and the incidence rate of depression symptoms was 59.8% (909/1521) . The workers who were aged <35 years, lived alone or in widowhood, or had an income of ≤4000 yuan tended to have a high score of depression tendency. And ordinary workers, oil-refining workers, workers with night shift and non-fixed shift, and workers with a lack of physical exercise and low sleep quality tended to have a high score of depression tendency (P<0.05) . The dimensions of extrinsic and intrinsic efforts of occupational stress and severity of occupational environment were positively correlated with depression (r=0.254, 0.242, 0.274, P<0.01) . And the dimension of reward was negatively correlated with depression (r=-0.348, P<0.01) . The multivariate hierarchical regression analysis showed that occupational stress and occupational environment had a marked predictive effects on depression, with an explained variance of 18.4% and 12.1%, respectively. Conclusion: There is a high level of depression tendency among workers in petrochemical enterprises, and demographic features, work conditions, lifestyle, occupational stressors, and occupational environment factors are influencing factors for depression.

An overview of compensated work-related injuries among Korean firefighters from 2010 to 2015

Background

Although one in two firefighters in South Korea have experienced work-related injuries, there are few studies which show the overview description on work-related injuries and its analysis regarding such causes. Therefore, we aimed to show the overview of compensated work-related injuries in order to serve fundamental data for establishing prevention policies on work-related injuries for Korean firefighters.

Methods

We requested the all claimed work-related injury data of Korean firefighters from 2010 to 2015 to the Korean National Fire Agency (NFA). The data from NFA including 2457 claimed cases was analyzed and we confirmed, 2154 approved work-related injuries for the kinds of job activities, cause of accident and type of injuries. Among 2154 approved cases, we analyzed more variables for the sex, age, and job duration of 1344 compensated cases through served text file on summary of accident.

Results

The Government Employees Pension Service (GEPS) recognized 2154 (87.7%) approved work-related injuries among 2457 claimed cases. The incidence of work-related injuries per 1000 firefighters was 9.8 persons. By region, the incidence of work-related injuries per 1000 firefighters ranged from a maximum of 14.5 to a minimum of 4.0. The most common job activity caused the accident was fire suppression (18.0%), followed by Emergency medical services (EMS) (17.5%) and training (10.7%). The most common cause of these accident was movement imbalance (30.3%), followed by falls (18.9%) and traffic accident (13.4%). In these work-related injuries, sprains and bruises were the most common type of injury (27.2%), and the most commonly injured body site was the upper and lower back (25.3%). Data from identified 1344 firefighters showed that 1264 (94.0%) were male and 80 (6.0%) were female. Age group was the highest in the 40s with 623 cases (46.4%), and job duration was the highest with 650 cases in 5-10 years (48.4%).

Conclusion

In this study, we could obtain the preliminary data necessary to establish preventive measures, including the cause of accident and region with high accident rates. However, the number of applications for compensated injuries was very small compared to the frequency of injuries found in previous studies. The lack of appropriate treatment suggested that many firefighter injuries can become chronic. In this study, we suggest that it is necessary to introduce an injury monitoring system and improve the accessibility of compensated injuries.

Trial registration

CR318031. Registered 20 June 2018.

Expansion of effective wet bulb globe temperature for vapor impermeable protective clothing

The wet bulb globe temperature (WBGT) is an effective measure for risk screening to prevent heat dISOrders. However, a heat risk evaluation by WBGT requires adjustments depending on the clothing. In this study, we proposed a new effective WBGT (WBGT_eff^*) for general vapor permeable clothing ensembles and vapor impermeable protective clothing that is applicable to occupants engaged in moderate intensity work with a metabolic heat production value of around 174W/m². WBGT_eff^* enables the conversion of heat stress into the scale experienced by the occupant dressed in the basic clothing ensemble (work clothes) based on the heat balances for a human body. We confirmed that WBGT_eff^* was effective for expressing the critical thermal environments for the prescriptive zones for occupants wearing vapor impermeable protective clothing. Based on WBGT_eff^*, we succeeded in clarifying how the weights for natural wet bulb, globe, and air temperatures and the intercept changed depending on clothing properties and the surrounding environmental factors when heat stress is expressed by the weighted sum of natural wet bulb, globe, and air temperatures and the intercept. The weight of environmental temperatures (globe and air temperatures) for WBGT_eff^* for vapor impermeable protective clothing increased compared with that for general vapor permeable clothing, whereas that of the natural wet bulb temperature decreased. For WBGT_eff^* in outdoor conditions with a solar load, the weighting ratio of globe temperature increased and that of air temperature decreased with air velocity. Approximation equations of WBGT_eff^* were proposed for both general vapor permeable clothing ensembles and for vapor impermeable protective clothing.

Urinary incontinence in women in relation to occupational status

Through this cross-sectional study the authors explore urinary incontinence in women in relation to occupational status and environment. Data from the fourth Korea National Health and Nutrition Examination Survey (2008-2009) were used (n = 5,928) excluding those aged under 19 or over 65 years, male, with renal disease, and with missing data. Urinary incontinence was prevalent in working women. Compared to unemployed women, the adjusted odds ratio (95% confidence intervals) for women working in services/sales was 1.62 (1.21-2.19); for paid workers was 1.81 (1.20-2.73); and for self-employed workers was 1.46 (1.05-2.03). Compared to unemployed women, the adjusted odds ratio for working women with a daytime work schedule was 2.14 (1.18-3.87), while for those with evening work schedules, it was 1.35 (1.05-1.74). Urinary incontinence was significantly associated with various occupational environments: an unclean and uncomfortable workplace, dangerous job and probability of accidents, feeling pressed for time, awkward position for long periods, and carrying heavy weights. These findings suggest that urinary incontinence was prevalent in working women and was associated with occupational status and working environment. Therefore, improving occupational status and environment for working women-such as modifying the working schedule, posture, and workplace atmosphere-are needed to prevent urinary incontinence.

Study the epidemiological profile of taxi drivers in the background of occupational environment, stress and personality characteristics

Background:

Work hazards have been a major cause of concern in driving industry especially in taxi drivers. This study integrates the various factors that influence physical and emotional well-being of taxi drivers into the theoretical model that shows that the work environment, stress and personality characteristics directly influence taxi drivers’ health.

Objective:

The aim of the following study is to study the relative and combined influence of work environment, personality characteristics and stress on the health of taxi drivers.

Meterials and Methods:

The present study is cross-sectional (descriptive) study taxi drivers in Mumbai. They are selected using multistage random sampling method. Calculated sample size is 508. Data produced after the survey is analyzed using IBM SPSS 16.0 software.

Results:

Nearly 65% of taxi drivers belonged to middle-age group of 21-40 years of age. Majority (59%) of taxi drivers belonged to the lower upper socio-economic class. 70% of taxi drivers worked for more than 8 h daily. 63% gave the history of one or more addictions. 52% taxi drivers had type B1 personality, only 6% had stress prone and aggressive type A1 personality. Traffic congestion (67.1%) was reported as the leading stressor followed by narrow bottle neck roads (43%), too many speed breakers (41%), rude gestures and behavior by other drivers (42%) and bad weather (36%). Nearly 86% taxi drivers had one or more symptoms of morbidities. Gastrointestinal symptoms predominated followed by musculoskeletal symptoms and depression.

Conclusion:

Socio-demographic attributes, work environment, stress and personality significantly influence physical and psychological morbidities in taxi drivers.

Construct validity of a work environment impact scale

This study examined the construct validity and the internal consistency of a newly developed assessment, the Work Environment Impact Scale (WEIS). After administration to 20 individuals with psychiatric disabilities, Rasch analysis was utilized to scrutinize the data. For this study, criteria for determining unexpected person/item responses were based on the following criteria: MNSQ > 1.3 and <formula>$\underline{t}>2.0$</formula>. Persons/items with MNSQ < 0.7 and <formula>$\underline{t}<-2.0$</formula> were examined to enhance instrument precision but were not considered misfit. Results suggest that the WEIS is an appropriate and valid instrument to utilize with workers who have psychiatric disabilities. Overall, the items appeared to match the worker's need for performance, satisfaction, and well-being as the mean of persons measure is 0.30 ± 0.49 logits more than the mean of items measured. In addition the hierarchical order of items is consistent with literature identifying environmental press and affordance for workers with psychiatric disabilities. WEIS items constitute a uni-dimensional construct given that the summary statistics for both item and person had a MNSQ of 1.00 and 1.02 respectively and both <formula>$\underline{t}$</formula> values were -0.2. However, three items exceeded the established criterion for being too informative given the MNSQ < 0.7 and a <formula>$\underline{t}<-2.0$</formula>., suggesting these needed to be revised to enhance the quality measurement of the instrument. One hundred percent of the workers fit the expected response pattern of the Rasch model suggesting that workers with greater satisfaction, performance and health had a higher degree of match with his/her occupational environment. In summary, anecdotal data suggested that the WEIS provided clinically relevant information useful for planning of work-related interventions or reasonable accommodations.