PHYSIOLOGICAL REACTION TO WORK IN COLD MICROCLIMATE

Abstract Objectives: In Poland, occupational exposure to cold microclimate is quite common (5.1 workers/1000 occupationally active people). Reports on health effects of this exposure are rather scarce. The aim of the study was to evaluate the physiological reaction in workers occupationally exposed to cold microclimate. Materials and Methods: Examinations were performed in a group of 102 workers (41 women and 61 men) employed at cold storage units. The mean age in the group was 39.1 ± 9.9 years and the duration of employment under conditions of cold environment was over 12 years. The study population was divided into four groups, according to microclimate conditions (group I, ambient temperature -26°C; group II, 10-14°C; group III, 18-20°C, control group; and group IV, 0-10°C). The workers underwent the following procedures: general medical examinations, cold pressor test, ambulatory blood pressure monitoring, and heart rate variability (HRV) analysis (time-and frequency-domain parameters). Results: The results were adjusted for confounding factors (age, smoking and drinking habits). The analysis of HRV parameters did not reveal any significant differences between the study groups. However, systolic and diastolic blood pressure (BP) in the daytime and at night was significantly higher in group IV compared to group II. Mean heart rate (HR) in the daytime and at night and the BP and HR day/night ratio did not differ between the groups. The analysis of BP by gender revealed that in women, systolic BP during the day and at night was significantly higher in group IV than in group II. In the group of workers with hypertension (18 men and 5 women), men reacted to the cold pressor test either by increased or decreased BP while all the women reacted by the increased BP. Conclusions: Our findings indicated that in workers exposed to cold microclimate, the physiological reaction was dependent on gender and ambient temperature. Women seemed to be more sensitive to cold stress than men. However, this finding must be further investigated

Prevention of cardiovascular diseases – Prophylactic program in a selected enterprise

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):757–76

Work fatigue in urban bus drivers

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. Med Pr 2015;66(5):661–67

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

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):27–4

Effect of stress and intesity of mobile phone using on the health and subjective symptoms in GSM workers

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):617–62

Effect of stress and intesity of mobile phone using on the health and subjective symptoms in GSM workers

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):617–62

The reaction of the circulatory system to stress and electromagnetic fields emitted by mobile phones – 24-h monitoring of ECG and blood pressure

Wstęp W badaniach eksperymentalnych zaobserwowano wpływ korzystania z telefonu komórkowego na pracę serca, m.in. wydłużenie odstępu QTc oraz zmiany w wartościach ciśnienia tętniczego. Także stres może wywoływać zmiany w układzie krążenia. Brak jednak badań uwzględniających jednoczesne oddziaływanie stresu i pola elektromagnetycznego (PEM). Oba czynniki dotyczą m.in. pracowników sieci komórkowych. Materiał i metody Spośród 208 badanych we wcześniejszych etapach metodą ankietową 55 osób wyraziło zgodę na udział w dalszych badaniach [EKG spoczynkowe, 24-godzinna rejestracja EKG i ciśnienia tętniczego (ambulatory blood pressure monitoring − ABPM)]. Oceniono u nich także stan zdrowia, poziom stresu zawodowego i ogólnego oraz ekspozycję na PEM. Wyniki W przypadku osób rozmawiających przez telefon komórkowy ponad 60 min dziennie ciśnienie skurczowe w pomiarze jednorazowym i ciśnienie skurczowe z nocy w badaniu ABPM były istotnie wyższe niż u rozmawiających krócej (odpowiednio, p = 0,04 i p = 0,036). Badani, u których stwierdzono najwyższy poziom stresu zawodowego, charakteryzowali się istotnie wyższym ciśnieniem skurczowym w okresie doby (p = 0,007) i dnia (p = 0,002), zarówno w pracy (p = 0,010), jak i po niej (p = 0,005), oraz wyższym ciśnieniem rozkurczowym w okresie dnia (p = 0,028). Reakcja układu krążenia była istotnie zależna od płci. U mężczyzn dominowały zaburzenia ciśnienia tętniczego, a u kobiet – zaburzenia przewodzenia w EKG. Częstość skurczów serca w okresie doby z uwzględnieniem wpływu płci, stresu ogólnego i PEM była istotnie skorelowana z poziomem stresu zawodowego. Wnioski Uzyskane dotychczas wyniki wskazują na potrzebę dalszych badań w celu wyjaśnienia przyczyn różnej u kobiet i mężczyzn odpowiedzi układu krążenia na działanie stresu i PEM emitowanego przez telefony komórkowe. Med. Pr. 2019;70(4):411–424Background 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):411–2