[Physiological cost of wearing protective masks - a narrative review of the literature]. / Koszt fizjologiczny noszenia masek ochronnych ­ narracyjny przeglad literatury.

Due to the controversy related to the necessity to wear protective masks and the negative perceptions of users, an attempt was made to analyze the available scientific research on the physiological consequences of wearing various types of masks. The literature review includes publications available in the PubMed bibliographic database, describing symptoms and complaints of mask users (e.g., the feeling of discomfort, fatigue, headaches), different physiological reactions depending on the type of mask (surgical masks, masks with an exhalation valve, with air flow, etc.) as well as the influence of air composition, temperature and humidity in the space under the mask. The impact of using the mask on the ability to exercise (maximal effort, moderate effort) and mental work was outlined. The consequences of wearing masks by people in a different physiological state (pregnancy) were discussed. Proposals for the organization of work were also presented in order to minimize the negative consequences for people wearing masks. The analysis of the presented studies shows that, regardless of the type of masks worn, they can intensify the body's reactions to a varying degree, increasing the physiological cost of work and worsening the ability to make both physical and mental effort. In addition, the mask can contribute, among others, to more frequent headaches, symptoms of fatigue or the subjective feeling of discomfort. However, despite these adverse effects, the use of masks is important to protect people against harmful factors in the work and communal environments, and during the current SARS-CoV-2 pandemic, it has become a necessity. The discomfort of wearing a mask can be reduced by taking appropriate breaks. It should be emphasized that the rhythm of work and breaks in wearing the mask should take into account the individual limitations of the employee. Med Pr. 2021;72(5):569-89.

[Aggravating factors in teachers' work and fatigue]. / Czynniki obciazajace w pracy nauczycieli a zmeczenie.

BACKGROUND: Teachers are a occupational group in which, due to the type and specificity of work, it can be expected that the feeling of fatigue will be very intense. However, there has been little research into this problem. The aim of the research was to assess the level of fatigue after work and chronic fatigue in teachers, and to determine whether and to what extent it depends on occupational and non-occupational loads. MATERIAL AND METHODS: The stratified sampling model was used to select the sample, where the layers were the type of school and its location (size of a town/city). All teachers from selected schools were invited to participate. Overall, 650 questionnaires were distributed and 403 teachers returned completed questionnaires. Fatigue after work was assessed on the basis of answers to the following question: "Do you feel tired after work?" and chronic fatigue using the Fatigue Assessment Scale. A special questionnaire was developed to assess other factors that might affect the level of fatigue. The Subjective Stress Assessment at Work Questionnaire, Cohen's Perceived Stress Scale, a part of the Questionnaire of Professional Loads of the Teacher and a list of additional factors disturbing the work were used. RESULTS: The study involved 70 men aged 35-63 years and 333 women (24-64 years). The groups did not differ significantly in terms of mean age. The level of fatigue, regardless of gender, was mostly influenced by time pressure, rush, mismanagement of the pace of work to individual abilities, increasing workload, an excess of responsible tasks, a lack of support from superiors, a low prestige of the profession, a lack of pedagogical successes, a sense of the lack of meaning in work, and the negative impact of work on family life, as well as non-occupational loads and insufficient rest. CONCLUSIONS: The conducted study allowed for determining the profile and frequency of occupational and non-occupational factors affecting the level of fatigue in teachers. Med Pr. 2021;72(3):283-303.

The effect of occupational exposure to noise on ischaemic heart disease, stroke and hypertension: A systematic review and meta-analysis from the WHO/ILO Joint Estimates of the Work-Related Burden of Disease and Injury.

BACKGROUND: The World Health Organization (WHO) and the International Labour Organization (ILO) are developing joint estimates of the work-related burden of disease and injury (WHO/ILO Joint Estimates), with contributions from a large number of individual experts. Evidence from mechanistic data suggests that occupational exposure to noise may cause cardiovascular disease (CVD). In this paper, we present a systematic review and meta-analysis of parameters for estimating the number of deaths and disability-adjusted life years from CVD that are attributable to occupational exposure to noise, for the development of the WHO/ILO Joint Estimates. OBJECTIVES: We aimed to systematically review and meta-analyse estimates of the effect of any (high) occupational exposure to noise (≥85 dBA), compared with no (low) occupational exposure to noise (<85 dBA), on the prevalence, incidence and mortality of ischaemic heart disease (IHD), stroke, and hypertension. DATA SOURCES: A protocol was developed and published, applying the Navigation Guide as an organizing systematic review framework where feasible. We searched electronic academic databases for potentially relevant records from published and unpublished studies up to 1 April 2019, including International Trials Register, Ovid MEDLINE, PubMed, Embase, Lilacs, Scopus, Web of Science, and CISDOC. The MEDLINE and Pubmed searches were updated on 31 January 2020. We also searched grey literature databases, Internet search engines and organizational websites; hand-searched reference lists of previous systematic reviews and included study records; and consulted additional experts. STUDY ELIGIBILITY AND CRITERIA: We included working-age (≥15 years) workers in the formal and informal economy in any WHO and/or ILO Member State but excluded children (<15 years) and unpaid domestic workers. We included randomized controlled trials, cohort studies, case-control studies and other non-randomized intervention studies with an estimate of the effect of any occupational exposure to noise on CVD prevalence, incidence or mortality, compared with the theoretical minimum risk exposure level (<85 dBA). STUDY APPRAISAL AND SYNTHESIS METHODS: At least two review authors independently screened titles and abstracts against the eligibility criteria at a first stage and full texts of potentially eligible records at a second stage, followed by extraction of data from qualifying studies. We prioritized evidence from cohort studies and combined relative risk estimates using random-effect meta-analysis. To assess the robustness of findings, we conducted sensitivity analyses (leave-one-out meta-analysis and used as alternative fixed effects and inverse-variance heterogeneity estimators). At least two review authors assessed the risk of bias, quality of evidence and strength of evidence, using Navigation Guide tools and approaches adapted to this project. RESULTS: Seventeen studies (11 cohort studies, six case-control studies) met the inclusion criteria, comprising a total of 534,688 participants (39,947 or 7.47% females) in 11 countries in three WHO regions (the Americas, Europe, and the Western Pacific). The exposure was generally assessed with dosimetry, sound level meter and/or official or company records. The outcome was most commonly assessed using health records. We are very uncertain (low quality of evidence) about the effect of occupational exposure to noise (≥85 dBA), compared with no occupational exposure to noise (<85 dBA), on: having IHD (0 studies); acquiring IHD (relative risk (RR) 1.29, 95% confidence interval (95% CI) 1.15 to 1.43, two studies, 11,758 participants, I2 0%); dying from IHD (RR 1.03, 95% CI 0.93-1.14, four studies, 198,926 participants, I2 26%); having stroke (0 studies); acquiring stroke (RR 1.11, 95% CI 0.82-1.65, two studies, 170,000 participants, I2 0%); dying from stroke (RR 1.02, 95% CI 0.93-1.12, three studies, 195,539 participants, I2 0%); having hypertension (0 studies); acquiring hypertension (RR 1.07, 95% CI 0.90-1.28, three studies, four estimates, 147,820 participants, I2 52%); and dying from hypertension (0 studies). Data for subgroup analyses were missing. Sensitivity analyses supported the main analyses. CONCLUSIONS: For acquiring IHD, we judged the existing body of evidence from human data to provide "limited evidence of harmfulness"; a positive relationship is observed between exposure and outcome where chance, bias, and confounding cannot be ruled out with reasonable confidence. For all other included outcomes, the bodies of evidence were judged as "inadequate evidence of harmfulness". Producing estimates for the burden of CVD attributable to occupational exposure to noise appears to not be evidence-based at this time. PROTOCOL IDENTIFIER: 10.1016/j.envint.2018.09.040. PROSPERO REGISTRATION NUMBER: CRD42018092272.

[Selected chronic diseases and their risk factors in teachers]. / Wybrane choroby przewlekle i ich czynniki ryzyka u nauczycieli.

Chronic diseases (ChDs) pose an essential problem from an individual, social and economic point of view. It is estimated that they account for 60% of all deaths worldwide, and this share is expected to rise to 72% by 2020. The most prevalent are cardiovascular diseases (30%), cancers (13%), respiratory diseases (7%), and diabetes (2%). Their major risk factors include unhealthy diet, the lack of physical activity, and tobacco smoking. Of significance are also occupational and environmental hazards. Among teachers, the factor with the highest impact is noise, reported by 25% of male and 38% of female teachers. In Poland, there are no databases on ChDs or risk factors in teachers; only voice disorders are well-recognized as an occupational disease. Only a few studies of health and lifestyle were conducted among teachers in Poland, but they cannot be generalized because they were carried out with different methods, in small groups of people and in various regions in the country. A representative study carried out by Statistics Poland (GUS) among education employees (with no separate data for teachers) revealed that the most prevalent were musculoskeletal disorders, including back-pain (21.9%), as well as painfulness of the neck, shoulder, hand, hip and leg (10% in each case). Headaches and eye fatigue were found in 14.6%; stress, anxiety and depression in 7.3%; and cardiovascular disorders in 4.6% of the study population. Defining health problems in this professional group is an important public health issue which should enable reducing the prevalence and adverse health effects of ChDs. Med Pr. 2020;71(2):221-31.

[Using of the ROSA method to assess the musculoskeletal load on computer workstations]. / Zastosowanie metody ROSA do oceny obciazenia ukladu miesniowo-szkieletowego na komputerowych stanowiskach pracy.

BACKGROUND: The aim of the study was to compare the musculoskeletal system load assessed using the rapid office strain assessment (ROSA) and rapid upper limb assessment (RULA) methods in computer operators, and to determine the correlation of the obtained results with the occurrence and intensity of musculoskeletal complaints (MSCs) in these individuals. MATERIAL AND METHODS: In a group of 72 persons (38 women and 34 men) working with a computer for > 4 h/day, the ROSA and RULA methods were used to assess the load, while a questionnaire modeled on the Standardized Nordic Questionnary was used to assess the frequency and severity of MSCs. RESULTS: Musculoskeletal complaints occurred in about 66% of the investigated women and 62% of the investigated men within the previous year. The results of the ROSA and RULA methods were not convergent. The final result of the ROSA method (scale 1-10 pts) was 2-6 pts (M = 3.51±1.09), while the final result of the RULA method (scale 1-7 pts) ranged 2-4 pts (3.00±0.17). The values of partial and final scores in the ROSA method were correlated with the number of concurrent ailments and intensity of complaints in various regions of the musculoskeletal system. The assessment of the position of particular parts of the body during work, performed using the RULA method, in people with or without MSCs was almost identical. CONCLUSIONS: The use of the ROSA method has shown that it is a useful and easy-to-use tool for assessing computer workstations and can be successfully disseminated. Med Pr. 2019;70(6):675-99.

Dietary habits and myocardial infarction in occupationally active men.

OBJECTIVES: Only a few studies have been undertaken to analyze the dietary habits of people with cardiovascular diseases. The aim of this study was to evaluate the dietary behaviors of working people who were hospitalized due to experiencing the first acute cardiovascular incident. MATERIAL AND METHODS: In the study, the Functional Activity Questionnaire was used. The study was conducted in 2 groups. The first group included all the men hospitalized during 1 year (January-December 2009) in 2 clinics of cardiology, who were professionally active until the first myocardial infarction (MI). It comprised 243 men aged 26-70 years. The reference group consisted of 403 men, blue- and white-collar workers, aged 35-65 years. RESULTS: The body mass index of the MI patients was significantly higher (p = 0.006). The frequency of consumption of particular products in the MI group and in the reference group differed significantly for 11 of 21 products. The MI patients significantly less frequently reported the daily consumption of fruit, raw vegetables, cheese, vegetable oils and fish. In this group, the consumption of salty (p = 0.0226) or fatty (p < 0.0001) foods was significantly higher. It was shown that, after adjusting for age, education and the type of work, the daily consumption of fish, salads and cooked vegetables, as well as fruit and vegetable oils, significantly reduced the risk of myocardial infarction. An increased MI risk was, in turn, associated with obesity and preference for fatty foods. CONCLUSIONS: The authors found that diet significantly modified the MI risk in the examined workers. This indicates that an important aspect of prevention activities among working people should involve education about proper dietary habits. Int J Occup Med Environ Health. 2019;32(6):853-63.

[The reaction of the circulatory system to stress and electromagnetic fields emitted by mobile phones - 24-h monitoring of ECG and blood pressure]. / Reakcja ukladu krazenia na stres i pole elektromagnetyczne emitowane przez telefony komórkowe ­ 24-godzinne monitorowanie EKG i cisnienia tetniczego.

BACKGROUND: Experimental studies have shown cardiovascular effects of electromagnetic fields (EMF) emitted by mobile phones (e.g., prolonged QTc interval and abnormal blood pressure [BP] values). Also, stress may have an impact on the cardiovascular function. However, there are practically no data regarding the joint effect of exposure to stress and EMF, with both factors pertaining, e.g., to employees of mobile network operators. MATERIAL AND METHODS: Out of 208 subjects who had taken part in survey research, 55 workers agreed to undergo resting ECG, 24-h ECG and ambulatory blood pressure monitoring (ABPM). Their health condition, occupational and life-stress levels and EMF exposure were also assessed. RESULTS: Among the workers using mobile phones for more than 60 min daily, the systolic BP values in office measurement and at night-time in ABPM were significantly higher than among the workers spending less time talking on mobile phones (p = 0.04 and p = 0.036, respectively). The workers with the highest level of occupational stress showed significantly higher systolic 24-h BP (p = 0.007) and at day-time (p = 0.002), both during work (p = 0.010) and after work (p = 0.005), and higher diastolic BP values at day-time (p = 0.028). Cardiovascular response was strongly gender-related: males showed more BP abnormalities while females displayed more impairments in ECG records. The heart rate from 24 h was significantly correlated with the level of occupational stress, after adjusting for gender, life-stress and EMF. CONCLUSIONS: The findings obtained thus far have indicated the need to conduct in-depth studies on the impact of stress and EMF emitted by mobile phones on the health effects, in order to clarify the observed gender-related differences in cardiovascular response to the combined exposure to stress and EMF. Med Pr. 2019;70(4):411-24.

WHO/ILO work-related burden of disease and injury: Protocol for systematic reviews of exposure to occupational noise and of the effect of exposure to occupational noise on cardiovascular disease.

BACKGROUND: The World Health Organization (WHO) and the International Labour Organization (ILO) are developing a joint methodology for estimating the national and global work-related burden of disease and injury (WHO/ILO joint methodology), with contributions from a large network of experts. In this paper, we present the protocol for two systematic reviews of parameters for estimating the number of deaths and disability-adjusted life years from cardiovascular disease attributable to exposure to occupational noise, to inform the development of the WHO/ILO joint methodology. OBJECTIVES: We aim to systematically review studies on exposure to occupational noise (Systematic Review 1) and systematically review and meta-analyse estimates of the effect of occupational noise on cardiovascular diseases (Systematic Review 2), applying the Navigation Guide systematic review methodology as an organizing framework, conducting both systematic reviews in tandem and in a harmonized way. DATA SOURCES: Separately for Systematic Reviews 1 and 2, we will search electronic academic databases for potentially relevant records from published and unpublished studies, including Medline, EMBASE, Web of Science and CISDOC. We will also search electronic grey literature databases, Internet search engines and organizational websites; hand search reference list of previous systematic reviews and included study records; and consult additional experts. STUDY ELIGIBILITY AND CRITERIA: We will include working-age (≥15 years) workers in the formal and informal economy in any WHO and/or ILO Member State, but exclude children (<15 years) and unpaid domestic workers. The eligible risk factor will be occupational noise. Eligible outcomes will be hypertensive heart disease, ischaemic heart disease, stroke, cardiomyopathy, myocarditis, endocarditis and other circulatory diseases. For Systematic Review 1, we will include quantitative prevalence studies of exposure to occupational noise (i.e., low: <85 dB(A) and high: ≥85 dB(A)) stratified by country, sex, age and industrial sector or occupation. For Systematic Review 2, we will include randomized controlled trials, cohort studies, case-control studies and other non-randomized intervention studies with an estimate of the relative effect of high exposure to occupational noise on the prevalence of, incidence of or mortality due to cardiovascular disease, compared with the theoretical minimum risk exposure level (i.e., low exposure). STUDY APPRAISAL AND SYNTHESIS METHODS: At least two review authors will independently screen titles and abstracts against the eligibility criteria at a first stage and full texts of potentially eligible records at a second stage, followed by extraction of data from qualifying studies. At least two review authors will assess risk of bias and the quality of evidence, using the most suited tools currently available. For Systematic Review 2, if feasible, we will combine relative risks using meta-analysis. We will report results using the guidelines for accurate and transparent health estimates reporting (GATHER) for Systematic Review 1 and the preferred reporting items for systematic reviews and meta-analyses guidelines (PRISMA) for Systematic Review 2. PROSPERO registration number: CRD42018092272.

Climate conditions and work-related fatigue among professional drivers.

The possible associations between climate parameters and drivers' fatigue have not been subject to specific studies thus far. We have undertaken a study to investigate whether the particular climate parameters are related to fatigue perception by motor vehicle drivers. The study was performed from July to October. Each driver was surveyed four times: before and after workshift on a monotonous route outside the city center (MR), and on a heavy traffic route in the city center (HTR). The study was conducted among 45 city bus drivers aged 31-58 years (43.7 ± 7.9), seniority as driver 3-34 years (14.7 ± 8.6). Data on climate conditions (ambient temperature, air pressure, humidity, wind speed, precipitations) on particular study days was obtained from the Institute of Meteorology and Water Management, National Research Institute Warsaw, Poland. Fatigue was assessed using the Fatigue Assessment Questionnaire, developed at Nofer Institute of Occupational Medicine (Lodz, Poland). The total level of fatigue was significantly (p = 0.045) higher after driving on HTR than on MR. The number of symptoms was also significantly higher (p < 0.05) among drivers working on HTR. After MR, significant correlations were found between wind speed and heavy eyelid feeling, being prone to forgetting, eye strain, frequent blinking, and between ambient temperature and feeling thirsty. After HTR feeling thirsty, tiredness and difficulty in making decisions correlated with ambient temperature and feeling thirsty with wind speed. Climate conditions can modify the drivers fatigue; therefore, we should be aware of their impact on well-being.

Analysis of bus drivers reaction to simulated traffic collision situations - eye-tracking studies.

OBJECTIVES: The aim of the study was to establish whether the driver's visual strategy may influence a driver's behavior to avoid a crash in a high-risk situation. Any published papers on drivers' visual strategies just before a crash were not found. MATERIAL AND METHODS: Tests were performed using a high-tech driving bus simulator. Participants comprised 45 men drivers, aged 43.5±7.9 years old, seniority as a bus driver of 13.3±8.6 years. The tests were preceded by medical examinations: general, neurological and ophthalmological. Each participant drove the same city route for approximately 40 min (entire route - ER). In the final phase, a collision situation was simulated (a phantom car blocked the participant's right of way). Driver's visual strategy was analyzed using the FaceLab device with 2 cameras during ER and just before collision. The field-of-view covered by camera 1 was divided into 8 regions, by camera 2 into 10 regions. The distribution of gazes in regions was a criterion of visual strategy. RESULTS: Thirty-five drivers completed the simulated driving test, 14 escaped the collision, 21 crashed. These groups differed only in resting systolic blood pressure before the test. The analysis of covariance, after adjusting to this factor, indicated that during the ER visual strategy recorded by camera 1 did not differ between groups, in camera 2 the drivers in the crash group fixed their gaze more frequently (p = 0.049) in region 3 (close part of the road in front of the windshield). Just before the collision drivers who escaped the collision fixed their gaze significantly more often in region 6 (left side of the road) in camera 1 and in region 6 (in front of the windshield,) and region 10 (right side) in camera 2. CONCLUSIONS: The visual strategy has an impact on the road safety. The analysis of visual strategies may be a useful tool for the training of drivers. Int J Occup Med Environ Health. 2019;32(2):161-74.

Electromagnetic fields exposure assessment among workers at broadcast centers in Poland.

BACKGROUND: In the studies investigating the potential health effects of occupational exposure to electromagnetic fields (EMF), the key problem is the assessment of workers' exposure. Electromagnetic fields exposure assessment requires determining maximum EMF levels, for the acute effect, and the dose absorbed, for the cumulative effect. A study was undertaken to determine EMF exposure in workers at broadcasting centers (BCs) in Poland. It was the first part of a comprehensive project on health effects of occupational exposure to EMF. MATERIAL AND METHODS: The study was conducted in 4 selected BCs. Spot measurements of electric field strength (E), and the results of E measurements that were made in the past for occupational hygiene assessments, were used for determining workers' exposure to electric field. The parameters considered were the maximum E value (Emax), the weighted average E value (Eavg) and the E lifetime dose (Elifetime dose). RESULTS: In the group of workers examined, the E values did not exceed 16.7 V/m for Emax (the occupational exposure limit (OEL) for work shift in Poland is 20 V/m), 2.9 V/m for Eavg and 1 500 000 (V/m)2×h for Elifetime dose. CONCLUSIONS: In view of the lack of dosimetry data, a retrospective assessment of BC workers' exposure to very high frequency and ultra-high frequency EMF was conducted, which made it possible to estimate EMF lifetime dose for the workers. Since the EMF exposure levels at BCs did not exceed the admissible values, they can be considered safe to the workers' health, according to the approach used for developing OELs for EMF exposure. Med Pr 2018;69(5):477-482.

[Prevention of cardiovascular diseases - Prophylactic program in a selected enterprise]. / Zapobieganie chorobom ukladu krazenia ­ program profilaktyczny wdrozony w wybranym przedsiebiorstwie.

BACKGROUND: In Poland cardiovascular diseases (CVD), classified as work-related diseases, are responsible for 25% of disability and cause 50% of all deaths, including 26.9% of deaths in people aged under 65 years. The aim of the study was to analyze employee expectations regarding CVD- oriented prophylactic activities in the selected enterprise. MATERIAL AND METHODS: A questionnaire, developed for this study, consists of: socio-demographic data, job characteristics, occupational factors, and questions about the respondents' expectations concerning the prevention program. The study group comprised 407 multi-profile company employees aged (mean) 46.7 years (standard deviation (SD) = 9.1), including 330 men (81.1%), mean age = 46.9 (SD = 9.2) and 77 women (18.9%), mean age = 45.9 (SD = 8.2) The study was performed using the method of auditorium survey. RESULTS: Employees declared the need for actions related to physical activity: use of gym, swimming pool, tennis (56.5%), smoking habits - education sessions on quitting smoking (24.6%). A few people were interested in activities related to healthy diet. According to the majority of the study group, the scope of preventive examinations should be expanded. Based on our own findings and literature data CVD- -oriented preventive program, addressed to the analyzed enterprise was prepared. The program will be presented in another paper. CONCLUSIONS: The results showed significant quantitative and qualitative differences in the classic and occupational CVD risk factors between men and women, as well as in preferences for participation in prevention programs. Therefore, gender differences should be taken into account when planning prevention programs. Med Pr 2017;68(6):757-769.

[Effect of stress and intesity of mobile phone using on the health and subjective symptoms in GSM workers]. / Wplyw stresu i intensywnosci rozmów przez telefon komórkowy na stan zdrowia i dolegliwosci subiektywne pracowników sieci GSM.

BACKGROUND: There are no available data on the health consequences that may result from the synergistic effects of electromagnetic fields (EMF) and stress. Understanding the mechanisms of the simultaneous exposure will make it possible to develop procedures to minimize adverse health effects in professionals using mobile phones. MATERIAL AND METHODS: A questionnaire survey was conducted in 600 randomly selected people to obtain data on their health status and the prevalence of subjective symptoms related to the mobile phones using. Among them, there were 208 GSM Network employees, to whom the Perceived Stress Scale and Assessment of Stress at Work Questionnaire were sent. Eighty-nine completed questionnaires were returned (response rate - 42.8%). RESULTS: The mean age of respondents was 30.3 years (standard deviation (SD) = 7.7), time of occupational use of mobile phone - 4.1 years (SD = 1.7), the level of occupational stress - 95.3 (SD = 19.1). A significant percentage of people (62.8%) complained of the frequent difficulties in coping with problems of everyday life, and 57.4% had a fairly frequent problems with managing their own affairs. Significant differences in the life stress were detected between groups with different time of phone use (p = 0.03), and in occupational stress level, significant differences were noted between the 2 groups differing in the length of the conversation (p = 0.05). The risk of headache, associated (odds ratio (OR) = 4.2, p = 0.008) or not associated (OR = 2.97, p = 0.04) with calls on mobile phone, adjusted for stress, was significantly higher in people speaking via mobile more than 60 min/day than in those talking less. CONCLUSIONS: The study indicates that both stressors acting at the same time (EMF from cell phone and stress) adversely affect the well-being of workers and increase the risk of subjective symptoms. Med Pr 2017;68(5):617-628.

Mobile phone use and risk for intracranial tumors and salivary gland tumors - A meta-analysis.

Results of epidemiological studies on the association between use of mobile phone and brain cancer are ambiguous, as well as the results of 5 meta-analysis studies published to date. Since the last meta-analysis (2009), new case-control studies have been published, which theoretically could affect the conclusions on this relationship. Therefore, we decided to perform a new meta-analysis. We conducted a systematic review of multiple electronic data bases for relevant publications. The inclusion criteria were: original papers, case-control studies, published till the end of March 2014, measures of association (point estimates as odds ratio and confidence interval of the effect measured), data on individual exposure. Twenty four studies (26 846 cases, 50 013 controls) were included into the meta-analysis. A significantly higher risk of an intracranial tumor (all types) was noted for the period of mobile phone use over 10 years (odds ratio (OR) = 1.324, 95% confidence interval (CI): 1.028-1.704), and for the ipsilateral location (OR = 1.249, 95% CI: 1.022-1.526). The results support the hypothesis that long-term use of mobile phone increases risk of intracranial tumors, especially in the case of ipsilateral exposure. Further studies are needed to confirm this relationship. Int J Occup Med Environ Health 2017;30(1)27-43.

[Work fatigue in urban bus drivers]. / Zmeczenie praca u kierowców autobusów miejskich.

BACKGROUND: Bus drivers are a special group of professional drivers who are at a very high risk of fatigue. The aim of the study was to examine whether the driver's subjective assessment of fatigue allows for the determination of its level and identification of its causes. MATERIAL AND METHODS: The study group comprised 45 randomly selected bus drivers (mean age - 43.7 ± 7.9 years, period of employment as drivers - 14.7 ± 8.6 years). Examinations were performed in all subjects four times - before and after work on the "easy" route (outside the city center, small traffic intensity) and before and after work on the "difficult" route (city center, heavy traffic). The fatigue test questionnaire, based on the list of symptoms of fatigue prepared by the Japan Research Committee of Fatigue, was used in the study. RESULTS: The rating of fatigue after the work was significantly higher than that before the work. The profile of fatigue after work was not influenced by the type of route, but the assessment of most symptoms of fatigue reached a higher level after the "difficult" routes and the differences were statistically significant for 7 symptoms. Only the ratings of leg fatigue, feeling of heaviness, and the necessity to squint eyes and gaze with effort reached the higher levels after driving the "easy" routes. It has been found that the level of fatigue was significantly correlated with the job characteristics (driving time, the length of the route, number of stops, etc.) and with the abundance of food ingested and type of beverage (coffee vs. others) drunk prior to driving. CONCLUSIONS: The questionnaire used in our study to assess the subjective feeling of fatigue has proved to be a sensitive and useful tool for indicating the level and causes of fatigue. The relationship between the symptoms of fatigue and the characteristics of job and lifestyle shows that actions must be taken by both the employers and employees to prevent fatigue in bus drivers.

[Neurological symptoms and syndromes in municipal transport drivers]. / Objawy i zespoly neurologiczne u kierowców pojazdów komunikacji miejskiej.

BACKGROUND: The way the municipal transport drivers perform their job contributes to varied burdens linked with the body posture at work, stress, shift work, vibration, noise and exposure to chemical agents. The aim of the study was to assess the condition of the nervous system (NS) in municipal transport drivers. MATERIAL AND METHODS: The study covered 42 men, aged 43.4 years (standard deviation (SD): 8.3), employed as bus drivers in the municipal transport enterprise. The duration of employment was 11.8 years on average (SD: 8.6). The condition of the nervous system was assessed on the basis of clinical neurological examinations. RESULTS: Chronic lumbosacral syndrome was found in 54.8% of the subjects. A significant relationship between the incidence of lumbosacral syndrome and the duration of employment (p=0.032) was observed; significantly higher in drivers employed for 11-15 years (90.9%) in comparison to the remaining groups. Nervous system functional disorders were characterized by the increased emotional irritability (47.6%), sleep disorders manifested by excessive sleepiness (33.3%) or insomnia (28.6%) and headaches (3%), mostly tension headaches. Excessive daytime sleepiness was significantly age-dependent (p=0.038). CONCLUSIONS: The evidenced NS disorders indicate the need to undertake preventive measures tailored for the occupational group of bus drivers.

The risk of subjective symptoms in mobile phone users in Poland--an epidemiological study.

OBJECTIVES: To assess the type and incidence of subjective symptoms related to the use of mobile phones in Polish users. MATERIAL AND METHODS: The study was conducted in 2005 using a questionnaire survey. Although it has been quite a long time, up to now, no such data have been published for Poland. The questionnaire consisted of 53 questions concerning sex, age, education, general health, characteristics of a mobile phone (hand-held, loud-speaking unit) as well as the habits associated with its use (frequency and duration of calls, text messages, etc.) and complaints associated with using a mobile phone. RESULTS: As many as 1800 questionnaires were sent. The response was obtained from 587 subjects aged 32.6 ± 11.3 (48.9% women, 51.1% men); the age did not differ significantly between men and women. The subjects owned a cell phone for an average of 3 years. Majority of the respondents used the phone intensively, i.e. daily (74%) or almost daily (20%). Headaches were reported significantly more often by the people who talked frequently and long in comparison with other users (63.2% of the subjects, p = 0.0029), just like the symptoms of fatigue (45%, p = 0.013). Also, the feeling of warmth around the ear and directly to the auricle was reported significantly more frequently by the intensive mobile phone users, compared with other mobile phone users (47.3%, p = 0.00004 vs. 44.6%, p = 0.00063, respectively). Most symptoms appeared during or immediately after a call and disappeared within 2 h after the call. Continuous headache, persisting for longer than 6 h since the end of a call, was reported by 26% of the subjects. CONCLUSIONS: Our results show that the mobile phone users may experience subjective symptoms, the intensity of which depends on the intensity of use of mobile phones.

Cardiovascular changes in workers exposed to fine particulate dust.

OBJECTIVES: Epidemiological studies provide evidence that airborne particulate matter may contribute to the increased incidence and mortality rates due to pulmonary and cardiovascular diseases. Only some of them address the problem of occupational exposure to particulate air pollution. The aim of our study was to assess cardiovascular reaction and autonomic regulation in workers exposed to fine particles. MATERIALS AND METHODS: All workers had medical examination, resting ECG with heart rate variability analysis (HRV), 24-h ECG, and ambulatory blood pressure monitoring (ABPM) performed. The subjects were 20 male workers (mean age: 32.14.0 year) of a ceramic ware factory exposed to the dust and 20 workers who were not exposed (mean age: 39.4±7.8 year). The period of employment under exposure amounted to 5.6±2.1 year. Dust exposure was measured using individual dosimeters. RESULTS: The geometric mean total dust concentration was 44±1.5 mg/m(3) and the FPD (fine particulate dust) concentration amounted to 11.5±1.6 mg/m(3). No abnormalities were noted in the resting ECG in both groups, in 24-h ECG 2 subjects, both from exposed and control groups, had ventricular heart rhythm and repolarization disturbances. Blood pressure in ABPM, both systolic as well as diastolic, was normal and did not differ between the groups. Resting heart rate in the exposed group was significantly lower (p = 0.038) than in the control group. In the exposed group STD R-R from short-term records was significantly higher (p = 0.01). Fast Fourier Transform (FFT) analysis showed that the low frequency power spectrum (LF) did not differ in the exposed and the control group, while high frequency (HF) was significantly higher in the exposed group. LF/HF ratio was significantly lower in the exposed in comparison with the control group. CONCLUSIONS: Although we did not reveal significant abnormalities in ECG as well as in ABPM in the exposed group, it seems that neurovegetative disturbances (parasympathetic predominance) may serve as an early indicator of fine particulate dust effect on cardiovascular system.

Heart rate variability (HRV) analysis in radio and TV broadcasting stations workers.

OBJECTIVES: The aim of the study was to assess the mechanism of cardiovascular impairments in workers exposed to UHF-VHF radio frequency electromagnetic fields (EMF). MATERIALS AND METHODS: Heart rate variability (HRV) was analysed using 512 normal heart beats registered at rest. The analysis concerned time-domain (STD R-R) and frequency-domain (VLF, LF, HF) parameters of HRV. Fifty nine workers (group I) with low-level and 12 workers (group II) with high-level exposure were examined. The mean age of the subjects was 47 ± 9 years and 41 ± 14 years, and mean exposure duration 19.1 ± 8.8 years and 13 ± 4 years, in groups I and II, respectively. The groups were divided according to: E(max), E(dose), E(mean) for frequencies UHF, VHF and UHF+VHF: The control group consisted of 42 non-exposed subjects, aged 49 ± 8 years. Statistical analysis comprised one-way analysis of variance, covariance analysis and logistic regression models. RESULTS: In the exposed groups, the heart rate was higher than in the control one. Standard deviation of R-R intervals (STD R-R) was found to be significantly (p = 0.0285) lower in group I (42.5 ± 24.7 ms) compared to the control group (62.9 ± 53.5 ms). The risk of lowered STD R-R was significantly increased (OR = 2.37, p = 0.023) in group II. Both exposed groups presented significantly higher VLF and LF values than the control group (p = 0.005 and p = 0.0025, respectively). The EMF-exposed groups were characterised by the dominance of the sympathetic system (LF/HF 1.3 ± 0.35). CONCLUSIONS: The results indicate that exposure to radiofrequency EMF may affect the neurovegetative regulation.

Changes in tympanic temperature during the exposure to electromagnetic fields emitted by mobile phone.

OBJECTIVE: Mobile phones generate microwave radiation which is absorbed by exposed tissue and converted into heat. It may cause detrimental health effects. The aim of the experiment was to check if exposure to EMF emitted by mobile phone influenced the tympanic temperature. MATERIAL AND METHODS: Human volunteer study was performed on ten healthy young men, aged 22.1±4.7 years, examined three times: 1. on a day with 2×60 min of no exposure (sham day), 2. on a day with continuous, 60 min exposure and 60 min of no exposure, 3. on a day with intermittent exposure (4×15 min "on" and 4×15 min "off"). Exposure was generated by mobile phone (frequency 900 MHz, SAR 1.23 W/kg). The study was double-blind, performed under controlled conditions (at 24°C and 70% humidity). The tympanic temperature (T(ty)) was monitored every 10 sec by a thermistor probe placed close to the aural canal membrane in the ear opposite the one in contact with mobile phone (contralateral position). Multivariate repeated-measures analysis of variance was used to calculate the results. RESULTS: The mean T(ty) in the whole group during continuous exposure was significantly higher than during sham exposure (p = 0.0001). During intermittent exposure the temperature was lower than during sham day (difference was up to 0.11°C). Within an hour after continuous exposure, T(ty) was higher by 0.03°C and after intermittent exposure T(ty) was lower by 0.18°C in comparison with sham day. Two hours after exposure T(ty) was significantly lower (p = 0.0001) than after sham exposure (0.06°C and 0.26°C respectively). The trends in T(ty) during experiment differed significantly in relation to exposure conditions (p < 0.05). CONCLUSIONS: The results of this analysis indicate that the physiological response to EMF exposure from mobile phone was mostly related to type of exposure (continuous or intermittent).