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1.
Scand J Work Environ Health ; 22(2): 85-93, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8738885

RESUMO

Health risks of power-frequency electric and magnetic fields (EMF) in the generation and transmission of electric power were investigated in a program comprising nine separate projects. The central objectives were to assess the practical importance of electric and magnetic field exposure as a health risk, to produce data applicable to field management measures at a major power company, and to support and spur research activities on electric and magnetic fields as environmental agents. Electric and magnetic fields seemed to be weak environmental factors, but the findings were uncertain and controversial as to the health risks except that, electric field strengths (about 1.5 kV.m-1) found even in the vicinity of 110 kV power lines may cause interference with cardiac pacemakers. There is still a need, however, for further basic research focused on the interaction mechanisms of electric and magnetic fields and biological tissue.


Assuntos
Fontes de Energia Elétrica/efeitos adversos , Campos Eletromagnéticos/efeitos adversos , Encéfalo/efeitos da radiação , Sistema Cardiovascular/efeitos da radiação , Criança , Cromátides/efeitos da radiação , Fontes de Energia Elétrica/normas , Instalação Elétrica/normas , Exposição Ambiental/efeitos adversos , Finlândia/epidemiologia , Humanos , Neoplasias Induzidas por Radiação/epidemiologia , Exposição Ocupacional/efeitos adversos , Marca-Passo Artificial , Características de Residência , Medição de Risco , Gestão da Segurança
2.
Bioelectromagnetics ; 16(6): 365-76, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8789067

RESUMO

In a specific case, the magnetic field generated in a building by a nearby power line is usually easy to calculate, although the accuracy of these calculations is sensitive to the quality of source information. To be able to study public health dimensions of magnetic field exposure (e.g., risk of cancer), it is necessary to evaluate the size and exposure of the population at risk. Relatively little quantitative information on public exposure to power-frequency magnetic fields of high-voltage power lines is available. This report describes residential exposure to magnetic fields from 110 kV, 220 kV, and 400 kV power lines in Finland at the national level, including 90% of the total line length in 1989. A geographical information system (GIS) was used to identify the buildings located near the power lines. After determining the distances between the lines and the buildings, historical data on load currents of these lines were used to calculate the magnetic fields. The residential magnetic field histories were then linked to the residents by means of a computerized central population register. The data obtained on personal exposure have also been utilized in a nationwide epidemiological study on magnetic field exposure of power lines and risk of cancer. The methods of exposure assessment and results of the number of buildings near 110 kV, 220 kV, and 400 kV power lines, their average annual magnetic fields, and personal exposure to magnetic fields from these lines are described. We found that 15,600 residents lived in an average residential magnetic field > or = 0.1 microT caused by power lines in 1989. The number of these residents increased fivefold during 1970-1989. We estimated that 0.3% of the population was exposed in their residences to an annual average magnetic flux density from 110 kV, 220 kV, and 400 kV power lines higher than 0.1 microT, the level that the background magnetic flux density in general does not exceed in Finnish homes. Thus, the problem of magnetic field exposure generated by high-voltage lines concerns only a relatively small fraction of the total population in Finland. However, the size and exposure of the population at risk remain somewhat arbitrary in practical multisource situations, as the biological interaction mechanism, the concept of harmful dose, and, in particular, the significance of the duration of exposure are unknown.


Assuntos
Magnetismo/efeitos adversos , Criança , Exposição Ambiental , Finlândia/epidemiologia , Habitação , Humanos , Neoplasias/epidemiologia , Neoplasias/etiologia , Medição de Risco
3.
BMJ ; 307(6909): 895-9, 1993 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-8241851

RESUMO

OBJECTIVE: To investigate the risk of cancer in children living close to overhead power lines with magnetic fields of > or = 0.01 microteslas (microT). DESIGN: Cohort study. SETTING: The whole of Finland. SUBJECTS: 68,300 boys and 66,500 girls aged 0-19 years living during 1970-89 within 500 m of overhead power lines of 110-400 kV in magnetic fields calculated to be > or = 0.01 microT. Subjects were identified by record linkages of nationwide registers. MAIN OUTCOME MEASURES: Numbers of observed cases in follow up for cancer and standardised incidence ratios for all cancers and particularly for nervous system tumours, leukaemia, and lymphoma. RESULTS: In the whole cohort 140 cases of cancer were observed (145 expected; standardised incidence ratio 0.97, 95% confidence interval 0.81 to 1.1). No statistically significant increases in all cancers and in leukaemia and lymphoma were found in children at any exposure level. A statistically significant excess of nervous system tumours was found in boys (but not in girls) who were exposed to magnetic fields of > or = 0.20 microT or cumulative exposure of > or = 0.40 microT years. CONCLUSIONS: Residentia magnetic fields of transmission power lines do not constitute a major public health problem regarding childhood cancer. The small numbers do not allow further conclusions about the risk of cancer in stronger magnetic fields.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Habitação , Neoplasias/etiologia , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Exposição Ambiental , Feminino , Finlândia/epidemiologia , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Neoplasias/epidemiologia , Características de Residência , Fatores de Risco
4.
Radiat Environ Biophys ; 32(4): 325-36, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8310127

RESUMO

Chromosomal aberrations, sister chromatid exchanges (SCEs), replication indices and micronuclei in peripheral blood lymphocytes were analysed among 27 nonsmoking power linesmen with considerable long-term exposure to 50-Hz electromagnetic (EM) fields, and among 27 nonsmoking telephone linesmen serving as a reference group, pairwise matched with the exposed workers for age and geographical region. Blood samples from the two groups were collected, cultured and analysed in parallel. No differences between the groups were observed on analysis of SCEs, replication indices or micronuclei. However, the mean rate of lymphocytes with chromatid-type breaks was higher among the power linesmen (0.96% gaps excluded, 1.41% gaps included) than among the reference group (0.44% and 0.70%, respectively). The excess of aberrant cells was concentrated among those power linesmen who had worked earlier in their life. Although the interpretation is somewhat complicated by the confounding effect of previous smoking, these results suggest that exposure to 50-Hz EM fields is associated with a slight increase in chromatid breaks.


Assuntos
Aberrações Cromossômicas , Campos Eletromagnéticos , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Exposição Ocupacional , Troca de Cromátide Irmã , Adulto , Humanos , Pessoa de Meia-Idade , Fumar
5.
Pacing Clin Electrophysiol ; 14(12): 2114-22, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1723194

RESUMO

The influence of the electromagnetic interference (EMI) on performance of 15 implanted cardiac pacemakers (12 generator models) was tested during exposure at a high voltage substation. All patients had an adequate spontaneous heart rate during the study. Tests were performed in the ventricular inhibited mode with unipolar sensing in all pacemakers and repeated with bipolar sensing in four pacemakers. The sensitivity was set to a regular, functionally proper level and then to the highest available level. Exposure was done to moderate (1.2-1.7 kV/m) and strong (7.0-8.0 kV/m) electric fields, which correspond to the immediate vicinity of 110 and 400 kV power lines, respectively. In moderate electric fields the output was inhibited in one pacemaker at regular sensitivity (1.7-3.0 mV) and in five pacemakers at the highest sensitivity (0.5-1.25 mV). In strong electric fields the output was inhibited in five pacemakers at regular sensitivity and several pacemakers converted to noise reversion mode at the highest sensitivity. In bipolar mode only one of four pacemakers at high sensitivity (0.5-1.0 mV) was inhibited in the strongest electric field, whereas all four did so in the unipolar mode. One pacemaker with unipolar sensitivity at 0.5 mV was interfered by 63 microT magnetic field. The results confirm that the programmed sensitivity level and the lead configuration markedly influence pacemakers' vulnerability to EMI. Bipolar sensing mode is rather safe in the presence of EMI, which is encountered in public environments. The programmable features of today's pacemakers permit individualized, less stringent safety measures to avoid electromagnetic hazards.


Assuntos
Campos Eletromagnéticos , Marca-Passo Artificial , Adulto , Eletricidade , Eletrocardiografia , Feminino , Frequência Cardíaca , Humanos , Magnetismo , Masculino , Pessoa de Meia-Idade
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