Biomedical subjects

E Gadzicka

Publications and source records attributed to E Gadzicka.

10 recordsLinked to original sources

PubMed2001

Cardiovascular disturbances in workers exposed to carbon disulfide.

According to literature data myocardial infarction was often the first noticeable effect of CS2 on the cardiovascular system. Therefore, a question arises whether earlier circulatory lesions are absent in CS2-exposed people, or they are present but are not detectable by the diagnostic methods used. The aim of our study has been to determine whether electrocardiological disturbances do occur in exposed people, and their association, if any, with the level of CS2 exposure. Modern diagnostic methods (resting and 24-h ECG, heart rate variability, late ventricular potential analysis, and long-term blood pressure monitoring) were used to answer this question. The examination comprised 177 male workers aged 24-66 years (44+/-12), employed under conditions of the exposure for 5-38 years (14+/-9), and 93 male workers non-exposed to CS2 aged 23-65 years (41+/-12). Results of our studies show that abnormalities in resting and/or 24-h ECG recordings occur significantly more frequently in people exposed to CS2 than in the controls. ECG abnormalities were found primarily among the workers with a long, over 20-year, period of exposure. The considerable coincidence between the questionnaire and ECG results was found (87% reported complaints were confirmed by ECG data). Therefore it seems that all CS2-exposed people reporting heart symptoms should be subjected to a detailed examination. The frequency of late ventricular potentials in CS2-exposed people was not higher than in the controls. It may indicate that the ECG disturbances observed in those people were associated with functional rather than organic changes. Results of long-term ABP monitoring did not show increased incidence of elevated blood pressure in the exposed group. As the levels of the risk factors of ischemic heart disease in the exposed and control groups were similar, it seems that exposure to CS2 was responsible for the significant changes in the circulatory system.

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PubMed1998

Alteration of diurnal rhythms of blood pressure and heart rate to workers exposed to radiofrequency electromagnetic fields.

BACKGROUND: In previous studies we found measurable effects on variability of heart rate and on blood-pressure parameters of workers exposed to radiofrequency electromagnetic fields (EMF)compared with a control population, but none of the effects could be assigned clinical significance. In general, the obtained results strongly suggested that dysregulation of the autonomic control of the circulatory system was occurring. Therefore, it seemed logical that analysis of diurnal rhythms of blood pressure and heart rate, on the basis of data from 24 h recordings, might further support the above hypothesis. OBJECTIVE: The aim of this study was to determine the course of diurnal rhythms of blood pressure and heart rate in a group of workers exposed to various intensities of radiofrequency electromagnetic fields. METHODS: In the study we used 61 healthy workers (aged 30-50 years) who had been exposed to radiofrequency EMF of 0.738-1.503 Mhz and 42 healthy workers at radio-line stations (aged 28-49 years), who had not been exposed to EMF occupationally. The work patterns of these two groups were identical (12 h day working shift, 24 h interval, 12 h night shift and then 48 h rest). During the second day of the rest period 24 h ambulatory blood pressure (ABP) was recorded. For analysis of diurnal rhythms the group of exposed workers was divided into two subgroups: group A of 38 subjects exposed to low intensities of radiofrequency EMF (20-180 V/m) and group B of 23 subjects exposed to high intensities of radiofrequency EMF (200-550 V/m). Parameters of diurnal rhythms of blood pressure and heart rate (acrophase, amplitude and mean) were calculated by performing a least-square fit of a 24 h cosinor (single cosinor analysis) at P < 0.05. RESULTS: Healthy men aged 28-49 years, working on a pattern of 12-24-12-48 h, exhibited typical, well-preserved diurnal rhythms of blood pressure and heart rate with two maxima (at about 1400 and 1700-1800 h) and one minimum (at about 0200-0400 h). For workers exposed to radiofrequency EMF we noted a significant lowering of the amplitudes of rhythms of blood pressure and heart rate (P < 0.01) and a shift of the acrophase to an earlier time (1100-1200 h; P < 0.05). These changes were more pronounced among workers exposed to high intensities of radiofrequency EMF. CONCLUSIONS: Occupational exposure to radiofrequency EMF can result in changes of the diurnal rhythms of blood pressure and heart rate with lowering of their amplitudes and a shift of the acrophase. The clinical relevance of the present finding needs to be investigated in further studies.

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PubMed1998

[Exposure to electromagnetic fields with frequencies of 50 Hz and changes in the circulatory system in workers at electrical power stations].

Bearing in mind a great diffusion of electromagnetic fields (EMF) with power-line frequency (in Poland-50 Hz) both in the occupational and communal environments, it is not surprising that possible health effects related to this exposure evoke much interest. Electromagnetic fields may affect the circulatory and nervous systems because of theoretical probability that electric impulses, generated by external electric and magnetic fields, may disturb their functions. For this reason we have decided to evaluate the functioning of the circulatory system in persons occupationally exposed to power-line frequency electromagnetic fields by employing the most up-to-date methods facilitating the in-depth diagnosis of the circulatory system and neurovegetative mechanisms. The work presented focused on the evaluation of electrocardiographic changes. The study covered 63 workers of the transforming and distributing stations, aged 22-67 years (median 39 +/- 10), employed under exposure for 2-43 years (median 15 +/- 10). The control group consisted of 42 workers of radio link stations, aged 23-65 years (median 30 +/- 14), employed in the similar system but not exposed to EMF, with employment duration of 1-42 years (median 13 +/- 4). All persons were subject to general medical examinations, resting ECG, and 24 h Holter monitoring. In addition, the level of exposure in individual workplaces was estimated following the measurements of the intensity of electric and magnetic fields. In workers of electromagnetic stations an increased risk for electrocardiographic disturbances was revealed. Under conditions of exposure to electric fields, observed in stations where workers were employed, the risk was increased by 10%.

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PubMed1997

Heart rate variability in workers exposed to carbon disulfide.

It is assumed that the cardiovascular impairments resulting from CS2 exposure may be associated with some functional disturbances within the autonomic nervous system. We adopted the heart rate variability (HRV) analysis to investigate the sympathetic and parasympathetic functions of the autonomic nervous system in workers exposed to carbon disulfide. The studies were performed on 152 workers, aged 24-66, with the period of exposure ranging from 5-38 years and 93 age-matched, non-exposed, healthy individuals as the control group. The HRV analysis concerned time-domain (AVG R-R, SD R-R, modal, median, minimum and maximum values) and frequency-domain indices (power spectrum in the very low-VLF, low-LF and high-HF frequency bands) calculated using the fast Fourier transformation. In the exposed group, neurovegetative regulation impairments could be observed. They were expressed as increased heart rate at rest, reduced power spectrum: total (TPS) and within HF, LF and VLF frequency bands as well as the absence of the physiological dependence of HRV parameters on age. These abnormalities could be found even in the group of workers exposed to the lowest CS2 levels (0-10 mg/m3) and they concerned the VLF band. In workers under conditions of exposure to 10-18 mg/m3 the dysfunction of the autonomic control referred both to its sympathetic and parasympathetic part and was found to be more intense in workers exposed to the highest CS2 concentrations (over 18 mg/m3). In view of our findings we concluded that occupational exposure to carbon disulfide may bring about an impaired neurovegetative regulation of the cardiovascular function.

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PubMed1997

[Evaluation of selected functional circulation parameters of workers from various occupational groups exposed to electromagnetic fields of high frequency. III. 24-h monitoring of arterial blood pressure (ABP)].

The problem of blood pressure regulation in persons occupationally exposed to electromagnetic fields (EMF) has not as yet been elucidated, and most data come from studies carried out long time ago (1960-70) in the former Soviet Union. Our study was aimed at verifying the Soviet data by means of modern methods. Together with traditional methods, a 24-h monitoring of arterial blood pressure (ABP) using a Medilog ABP kit (Oxford) were employed. Measurements were taken automatically every 0.5 h during daily activities and every 1 h during the night rest (about 41 measurements/day). The mean systolic and diastolic blood pressure and heart rate were calculated over day (BPSDOver, BPDOver, HROver), during daily activities (HPDD, BPSD, HRD) and during the night rest (BPSN, BPDN, HRN). The subjective and objective examinations were carried out as well as resting ECG and a 24-h Holter were performed (the results have been published earlier). The study covered male workers of middlewave broadcast stations (71), radioservice (40) and radio line stations (42). The subjects were aged 21-60 years and the duration of their work with devices generating high frequency EMF ranged between 1 and 42 years. The first group of workers was exposed to EFM at the frequency of 1 Mhz, the second at about 150 Mhz and the third group, not exposed, served as the control group. The study revealed that the mean arterial blood pressure and the day/night blood pressure variability indicator showed no significant differences between the groups, whereas the daily heart rate was significantly lower in the workers of middlewave broadcast stations in comparison with the controls despite similar type of work as far as physical effort and psychic burden are concerned, and similar non-occupational activities. The day/night heart rate variability indicator was significantly lower in the groups exposed. The decreased value of this indicator may suggest the occurrence of disorders in the neurovegetative regulation. In persons employed at radioservice stations a higher incidence of the increased arterial blood pressure, in comparison with the control group, was observed.

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PubMed1996

Heart rate variability in workers exposed to medium-frequency electromagnetic fields.

This study was undertaken to evaluate the neurovegetative regulation of the heart in workers occupationally exposed to medium frequency (MF) electromagnetic (EM) fields. The subjects were 71 workers of MF broadcast stations, aged 20-68 (mean 47.1) with the duration of work under exposure ranging from 2-40 years and 22 workers of radio link stations, aged 21-65 (mean 46.9) who were not exposed to MF EM fields. The distribution of age and work tenure in both groups did not differ significantly. Heart rate variability (HRV) was analysed basing on 512 normal heart evolutions registered in resting, from the body surface, using the Medea-HRV system. The analysis concerned time-domain and frequency-domain parameters of HRV using fast fourier transformation. Power spectrum in the low (0.05-0.15 Hz) and high (0.15-0.35 Hz) frequency bands (LF and HF, respectively) was determined. Statistically insignificant differences found between exposed and non-exposed groups were found either in time- or in frequency-domain parameters of HRV. No correlation between the power spectrum and the subjects age was noted. Such a relationship, however, could be observed in the control group. In the study group a statistically significant negative correlation was found between the maximum intensity of EM fields and HF power spectrum. Thus it was concluded that occupational exposure to EM fields brings about impairments in the neurovegetative regulation of the cardiovascular function.

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PubMed1996

[Evaluation of selected parameters of circulatory system function in various occupational groups exposed to high frequency electromagnetic fields. II. Electrocardiographic changes].

The effect of electromagnetic fields (EMF) on the circulatory and nervous systems has been the subject of great interest for many years, since electric impulses generated in these systems by outer electric and magnetic fields can theoretically disturb their functions. The only data on chronic effect of weak EMFs on the human body come from the studies carried out in the Soviet Union between the fifties and the seventies. In view of a growing number of persons exposed to EMF, there is an urgent need for verifying those data by means of modern diagnostic methods. That is the reason why our study of the EMF effect on the circulatory system has been initiated. It covered 71 workers at four AM broadcast stations, 40 workers at ten radio link stations and 42 workers at three radioservices. Workers' exposure to EMF was evaluated (see part I). Subjective and objective medical examinations were performed in all workers in order to assess their state of health, then resting electrocardiogram, Holter measurements, and high intensity ECG were taken, and variation in cardiac rhythm was analysed by a long-term recording of blood pressure. The results of the analysis of the questionnaire survey as well as the Holter and resting ECG examinations are presented. The study indicated that exposure to EMF in parameters found in AM broadcast station increased risk for electrographic disturbances (detected by means of resting ECG and a 24-hour Holter recording) by six times in comparison with that in radio link station workers not exposed to medium wave EMF. In radioservice workers this risk was twice as high as that in link station workers. It seems that in AM broadcast station workers, resting ECG should be complemented by a 24-hour Holter measurements, particularly, if workers complain of the circulatory system disturbances.

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PubMed1988

[A method of evaluating physical exertion during work based on the assessment of work capacity].

A method of calculating the synthetic index of effort capability, based on results of submaximal effort test, has been presented. Examinations of people working at 4 workstations demonstrated that the reduced effort capability after work is proportional to work energetic expenditure. The usefulness of work fatigue analysis has been indicated, as its magnitude, when accompanied by evaluation of effort capability changes, points to static load as an additional disadvantageous factor.

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PubMed1987

[Physical work capacity of women performing light and moderate tasks].

The studies have been aimed at answering the question whether or not a slight difference in the energetic and physiologic expenditure of work performed for many years affects the level of workers' physical fitness. A hundred women performing light (seamstresses) and moderate (formers) work have been examined. The physical fitness has been determined by a submaximum effort test. It seems that a work that only slightly exceeds the moderate and light work limits when added to everyday non-occupational tasks, results in reduced fitness.

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PubMedDate not supplied

Ambulatory ECG monitoring in workers exposed to electromagnetic fields.

The aim of this study was to evaluate the function of the circulatory system in workers occupationally exposed to medium frequency electromagnetic fields. The subjects were 71 workers at four AM broadcast stations [0.738-1.503 MHz] aged 20-68 (mean 46.9 +/- 13.1) years and 22 workers at radio link stations aged 23-67 (mean 48.2 +/- 17.4) years. Workers at AM broadcast stations experienced 2-40 (mean 18.6 +/- 12.1) years' exposure to electromagnetic fields (average daily exposure dose about 115 Vh m-1, maximum exposure levels during shift about 165 V m-1), workers at radio link stations had no history of regular exposure to electromagnetic fields. In all the subjects a general medical examination, resting ECG and 24 h Holter monitoring were performed. The work organization, work period structure, age, lifestyle, nutritional habits and health status in both groups remained fairly similar. The electrocardiographic abnormalities detected in the resting and/ or 24 h ECG were significantly more frequent (p = 0.006) in workers exposed to electromagnetic fields than in non-exposed subjects (75% versus 25%). A clear tendency for a higher number of rhythm disturbances (mostly ExV) was observed in AM broadcast station workers.

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