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Valutazione della genotossicità dei Campi Magnetici a Frequenza Estremamente Bassa (ELF- MF) in lavoratori esposti per ragioni professionali [Evaluation of the genotoxicity of the extremely low frequency-magnetic fields (ELF-MF) in workers exposed for professional reasons]
No full textWhether or not ELF-MF has genotoxic potential is a controversial issue. In the present study, we investigated the genotoxic effect using cytogenetic assays (CA - SCE - MN), in 109 workers exposed to ELF-MF. The mean value of occupational exposure in the whole group was 0.35 microT. According to the exposure level the workers were stratified in two different groups: low exposed (n. 39, TWA < or = 0.2 microT) and higher exposed (n. 70; TWA > 0.2 microT): the groups did not significantly differ for the examined variables. Due to these results we decided to re-evaluate the effect only considering the highest exposed workers: we selected 31 workers exposed to TWA levels exceeding 1 microT, and compared vs. the low exposed subjects: again, the difference in the groups examined were not significant. At multivariate regression analysis was also applied: no correlation was observed with cytogenetic biomarkers. The results of this study does not support the hypothesis of any direct genotoxic effect of ELF-MF, at least at the environmental levels currently found in an occupational settings
Genotoxicity of occupational exposure to EMF: comparison of workers exposed to different levels of extremely low frequency-magnetic fields (ELF-MF) and co-exposed to ELF-MF and VLF-MF.
No full textNatural killer activity in peripheral blood Lymphocytes of workers exposed to different levels of ELF-MF
No full textNo association between occupational exposure to ELF magnetic field and urinary 6-sulfatoximelatonin in workers
No full textA suppression in melatonin secretion is one of the mechanisms proposed to explain the possible adverse effects of extremely low frequency magnetic fields (ELF-MF), but the results of research are inconclusive. This study investigated the effect of occupational ELF-MF exposure on 6-sulfatoximelatonin (6-OHMS). Exposure was monitored for three complete work shifts in 59 workers using personal exposure meters. Environmental exposure was also evaluated. Urinary 6-OHMS in morning samples, an indicator of night-time melatonin production, was measured. Urine was collected twice on Friday and the following Monday. Workers were classified according to ELF exposure as low exposed (≤0.2 μT) or higher exposed (>0.2 μT): 6-OHMS did not differ between groups (P > .05) in either Friday or Monday urine samples. In addition, 6-OHMS was not related to exposure under multivariate analysis. The ratio between 6-OHMS in Monday versus Friday samples was also calculated to test the hypothesis of a possible variation in pineal function after 2 days, interruption of occupational ELF-MF exposure: again no exposure-related difference was observed. Our results do not support the hypothesis that occupational exposure to ELF-MF significantly influences melatonin secretion
ELF-MF occupational exposure: repeated measures on workers.
No full textThe aim of our study was to estimate occupational exposure to Extremely Low Frequency-Magnetic Fields (ELF-MF). Using personal dosimeters we evaluated occupational exposure in 543 workers employed in 9 occupational settings (about 150 jobs), representative of the main occupational activities in Emilia-Romagna region. In the whole sample, the median Time-Weighted Average (TWA) exposure resulted 0.14 microT (5 degrees - 95 degrees percentiles: 0.04 - 2.50 microT); Tile production presented the highest occupational setting TWA (0.46 +/- 1.83 microT), while the lower job TWA was Stock Clerk in Tile Production and Stock Clerk in Garment Production. After 6-9 months we repeated measurement in about 10% of the original sample (about 48 subjects) to verify the resulted obtained. At repeated measurement analysis with SPSS 12.0 no variation was found compared the previous monitoring. Individual occupational exposure to ELF-MF evaluated in a relatively large group of workers engaged in the main occupational activities proved low values compared to the proposed occupational limit
Personal exposure to ELF magnetic fields in workers engaged in various occupations.
No full textUsing personal dosimeters worn during two complete work-shifts, we measured occupational exposure to Extremely Low Frequency-Magnetic Fields (ELF-MF) in 290 workers employed in 56 jobs, representative of the main occupational activities in the area of Modena and Reggio Emilia (Italy). Environmental nonoccupational exposure was also monitored. In the whole sample, the mean Time-Weighted Average (TWA) exposure during work resulted 0.59 microT (SD 3.2), while the median was 0.13 microT. Exposure was lower than 1 microT in more than 90% of the workers. In one job only exposure was greater than 1 microT (job-related median TWA); in other 8 exposure was between 1 and 0.4 microT, while about 84% of the jobs presented a median TWA lower than 0.4 microT. A high variability among workers engaged in the same job resulted in various occupational tasks. Non-occupational exposure was lower than 0.4 microT in more than 98% of the examined workers. Our results show a low to moderate occupational exposure to ELF-MF in the greatest part of the workers and working activities. Also the non-occupational exposure resulted low in the large majority of the subjects. The high variability observed among workers engaged in some occupations may represent a problem in exposure evaluation. Personal monitoring is particularly useful in such a situations
Extremely Low Frequency-Magnetic Fields (ELF-EMF) occupational exposure and natural killer activity in peripheral blood lymphocytes
No full textExtremely Low Frequency-Magnetic Fields (ELF-MF) are possible carcinogens to humans and some data suggest that they can act as promoters or progressors. Since NK cells play a major role in the control of cancer development, an adverse effect on ELF-MF on NK function has been hypothesized. We examined NK activity in 52 workers exposed to different levels of ELF-MF in various activities. Individual exposure was monitored during 3 complete work-shifts using personal dosimeters. Environmental exposure was also monitored. ELF-MF levels in the workers were expressed as Time-Weighted Average (TWA) values. NK activity was measured in peripheral blood lymphocytes (PBL). In the whole group the median occupational TWA was 0.21 μT. According to the TWA levels, workers were classified as low exposed (26 subjects, TWA ≤ 0.2 μT) and higher exposed workers (26 subjects; TWA > 0.2 μT). In higher exposed workers, we observed a trend to reduce NK activity compared to low exposed, but the difference was not significant. Then we selected a subgroup of highest exposed workers (12 subjects; TWA > 1 μT); no difference was observed between low and highest exposed subjects in the main personal variables. Considering both E:T ratios from 12:1 to 50:1 and Lytic Units, a significant reduction in NK activity was observed in the highest exposed workers compared to the low exposed. Multivariate analysis showed a significant negative correlation between exposure and LU, while no correlation was evidenced with other personal characteristics. ELF-MF are considered possible carcinogens, and existing data suggest that they can act as promoters. Due to the role of NK activity in host defence against cancer, the results obtained in this study in workers exposed to ELF-MF levels exceeding 1 μT are in agreement with this hypothesis, and support the need for further investigation in this field
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