Global evidence on occupational sun exposure and keratinocyte cancers: a systematic review.

Individual studies have suggested that the association between occupational exposure to solar ultraviolet radiation (UVR) and the development of keratinocyte cancers (KCs) may only be valid in populations of European ancestry living in certain geographical regions. Comparative global data are scarce and so this review aimed to summarize current evidence on the association between occupational exposure to solar UVR and the development of KCs, with a specific focus on geographical location and skin colour. Ovid MEDLINE, PubMed, Embase and Web of Science were searched for potentially relevant records. Extracted data were summarized by study, country and region. We included one prospective cohort study and 18 case-control studies (n = 15 233) from 12 countries in regions where the majority of the population is white skinned (Americas, Europe and Oceania). Eighteen of the 19 studies reported effect estimates suggesting an increased risk of basal cell carcinoma (BCC) and/or squamous cell carcinoma (SCC) among outdoor workers. Only 11 studies found a significantly increased risk and many had imprecise estimates. There was a significantly increased risk of BCC and SCC in individual studies in North America, Latin America and the Caribbean, Western Europe and Southern Europe, but not across regions or countries. Overall, 95% of studies reported higher risks among outdoor workers, although the increases in risk were statistically significant in just over half of the studies. Well-designed and sufficiently powered occupational case-control and cohort studies with adequate adjustment for confounding factors and other risk factors are required to provide more accurate risk estimates for occupational KC.

Personal solar ultraviolet radiation dosimetry in an occupational setting across Europe.

BACKGROUND: Work-related solar ultraviolet radiation (UVR) is an important factor in the pathogenesis of non-melanoma skin cancer (NMSC). The World Health Organization, through the International Agency for Research on Cancer, has classified solar UVR as a group 1 carcinogen since 2012. The main problems encountered so far in the study of occupationally induced skin cancer include the lack of accurate occupational UVR dosimetry as well as insufficient distinction between occupational and leisure UVR exposure and underreporting of NMSC. OBJECTIVES: The aim of this study was to collect long-term individual UVR measurements in outdoor workers across European countries. METHODS: A prospective study was initiated through the European Academy of Dermatology and Venereology, Healthy Skin@Work Campaign, measuring UVR exposure doses at occupational settings of masons from five European countries. Measurements were performed for several consecutive months using the GENESIS-UV measurement system. RESULTS: The results identified alarming UVR exposure data. Average daily UVR doses ranged 148.40-680.48 J/m2 in Romania, 342.4-640.8 J/m2 in Italy, 165.5-466.2 J/m2 in Croatia, 41.8-473.8 J/m2 in Denmark and 88.15-400.22 J/m2 in Germany. Results showed an expected latitude dependence with increasing UVR yearly dosage from the north to the south of Europe. CONCLUSIONS: This study shows that outdoor workers from EU countries included in this study are exposed to high levels of occupational solar UVR, vastly exceeding the occupational exposure limits for solar UVR exposure, considered to be 1-1.33 SED/day in the period from May to September. This finding may serve as an evidence-based recommendation to authorities on implementing occupational skin cancer prevention strategies.

Skin cancer in outdoor workers exposed to solar radiation: a largely underreported occupational disease in Italy.

BACKGROUND: Solar UV radiation (sUVR) is one of the main carcinogen exposures in occupational settings, and UV-induced skin cancers are the most frequent tumours in fair-skinned individuals worldwide. OBJECTIVES: According to this premise, we should expect a high number of occupational skin cancers reported to the national workers' compensation authorities each year, also considering that the incidence of skin cancers has been constantly increased in recent years METHODS: We examined the data on reported non-melanoma skin cancers (NMSC) and actinic keratoses (AK) to the Italian National Workers Compensation Authority (INAIL) from 2012 to 2017, and we compared the number of reported skin cancers for outdoor workers with the expected numbers, obtained from currently available NMSC incidence rates for the Italian population applied to the occupational sUVR-exposed workers estimated with the CAREX methodology in Italy in 2005. RESULTS: The cases of NMSC reported each year to INAIL in Italy are 34 per year on average, while for AK the mean number of reported cases is of only 15/year. We estimated a number of expected NMSC cases in Italy for solar UV-exposed workers ranging between 432 and 983, representing a proportion between reported vs. expected skin cancers of only 3.5-6.2%. CONCLUSIONS: Our study clearly shows that occupational skin cancers in Italy are largely underreported, and, accordingly, urgent initiatives should be taken to raise appropriate awareness to the problem of occupational sUVR-induced skin cancers, so that adequate preventive measures can be implemented rapidly.

Questionnaire-based evaluation of occupational and non-occupational solar radiation exposure in a sample of Italian patients treated for actinic keratosis and other non-melanoma skin cancers.

BACKGROUND: An adequate evaluation of the ultraviolet (UV) cumulative exposure is a major problem in epidemiological studies on chronic skin damage. Questionnaires may be applied as useful tools. OBJECTIVE: We developed an original questionnaire to evaluate individual cumulative exposure to solar radiation (SR) in patients affected by actinic keratosis (AK), basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). METHOD: The questionnaire, considering both working and leisure exposure, was applied to evaluate the whole life history of solar UV radiation exposure in a group of patients of the Dermatologic Clinic of UNIMORE. RESULTS: In outdoor workers (OW), the co-presence of AK/in situ SCC and invasive non-melanoma skin cancers (NMSCs) was increased compared to indoor workers (IW), as was the frequency of multiple skin lesions. The prevalence of skin lesions of the face was significantly higher in OW. Work 'sometimes' or 'often' in the shades was associated with an absence of skin lesions on the shoulders and neck, while workers adopting 'sometimes' or 'often' a downward bent position were more likely to develop lesions on the top of the head. Considering leisure activities, the use of tanning beds was associated to the presence of skin lesions on the shoulders, neck and chest. Considering vacation periods, subjects spending at least 2 h outdoor in the period 11 am to 1 pm presented earlier diagnoses of skin cancers. CONCLUSION: Results of the original questionnaire developed are coherent with current knowledge and confirm the important role of UV exposure, both occupational and recreational, in the development of AK and NMSCs. Data support the hypothesis that this questionnaire can be applied as useful tool for the evaluation of cumulative UV exposure in future epidemiological studies.

The European Status Quo in legal recognition and patient-care services of occupational skin cancer.

BACKGROUND: Skin cancer is the most common malignancy in Caucasian populations worldwide and ultraviolet radiation (UVR) is known for being the number one carcinogen. As, especially in outdoor workers, UVR is an inevitable carcinogen, the prevention and management of UVR-related skin cancers in these at-risk populations represent a collective challenge for dermatologists and healthcare policymakers likewise. OBJECTIVE: To provide an overview on the current regulations on the acknowledgement and management of work-related skin cancer in 11 European countries. METHODS: Dermatologists from 11 countries networking within the EU Horizon 2020 COST Action TD1206 'StanDerm' contributed to a standardized survey regarding current national regulations, implemented for the recognition, prevention and management as well as possible compensation regulations in their individual country of residence. RESULTS: Ten of 11 participating countries in this survey reported the existence of an established programme available on certain occupational diseases; work-related skin diseases were only specifically recognized in eight countries. Seven of 11 countries recognize cutaneous squamous cell carcinoma in outdoor workers as 'occupational skin cancer'. Basal cell carcinoma (6 of 11), actinic keratosis (5 of 11), Bowen's disease (5 of 11) and malignant melanoma (5 of 11) are not as regularly approved as potentially 'work-induced'. Only a few of the countries included into this survey established a general documentation system (national registry) on occupational skin diseases. So far, representatives of only three countries of this survey referred to a specific established national programme for the prevention, management or compensation of occupational skin cancers acquired during work-related UVR exposure. CONCLUSION: This survey highlights the need for mandatory regulations on the prevention, management and potential compensation of work-related UV-induced skin cancer across Europe. Against the background of a joint European domestic market, equal standards of occupational safety across Europe should include binding regulations for the protection and management of work-related skin cancer. The design of a common regulation to meet the increasing incidence of skin cancers in outdoor workers should become part of the European agenda, ensuring equal working and living conditions in the member states.

Subjective symptoms and their evolution in a small group of magnetic resonance imaging (MRI) operators recently engaged.

Using a specific questionnaire, we examined subjective symptoms in a group of 17 physicians (9 males and 8 females, mean age 32.9 ± 3.71), attending a Postgraduate Medical School in Radiology and engaged in MRI for less than 1 year. Sixteen subjects (94%) reported the presence of at least one of the investigated symptoms during the period of MRI activity. The main symptoms were: unusual drowsiness/tiredness (88%), concentration problems (82%), headaches (76%), sleep disorders (47%), nausea (47%), illusion of movement (47%) and dizziness/vertigo (35%); the former two were subjectively related to MRI by the majority of the operators. These symptoms appeared (or worsened) in more than 15 min and, in the vast majority disappeared 30 min, or more, after the end of exposure. In 13 subjects (81%), the symptom (or some symptoms) appeared at least weekly. In this small group of health care workers recently exposed to MRI, the prevalence of subjective symptoms was higher than reported in other similar studies but, notably, the majority of subjects (77%) reported a regression within 4-8 weeks, suggesting some form of adaptation.

[Solar radiation exposure in agriculture: an underestimated risk]. / Esposizione a radiazione solare in agricoltura: un rischio sottovalutato.

Solar Radiation (SR) is a major occupational risk in agriculture, mainly related to its ultraviolet (UV) component. Available data show that UV occupational limits are frequently exceeded in these workers, resulting in an increased occupational risk of various acute and chronic effects, mainly to skin and to the eye. One of the foremost is the carcinogenic effect: SR is indeed included in Group 1 IARC (carcinogenic to humans). UV exposure is related to an increase of the incidence of basal cell carcinoma and squamous cell carcinoma of the skin, and cutaneous malignant melanoma (CMM). The incidence of these tumors, especially CMM, is constantly increasing in Caucasians in the last 50 years. As a conclusion, an adequate evaluation of the occupational risk related to SR, and adequate preventive measures are essential in agriculture. The role of the Occupational Physician in prevention is fundamental.

[Occupational risk related to optical radiation exposure in construction workers]. / Rischio da radiazione ottica in edilizia.

Optical Radiation is a relevant occupational risk in construction workers, mainly as a consequence of the exposure to the ultraviolet (UV) component of solar radiation (SR). Available data show that UV occupational limits are frequently exceeded in these workers, resulting in an increased occupational risk of various acute and chronic effects, mainly to skin and to the eye. One of the foremost is the carcinogenic effect: SR is indeed included in Group 1 IARC (carcinogenic to humans). UV exposure is related to an increase of the incidence of basal cell carcinoma, squamous cell carcinoma of the skin and cutaneous malignant melanoma (CMM). The incidence of these tumors, especially CMM, is constantly increasing in Caucasians in the last 50 years. As a conclusion, an adequate evaluation of the occupational risk related to SR, and adequate preventive measures are essential in construction workers. The role of occupational physicians in prevention is fundamental.

[Possible consequence on measures for the protection of electromagnetic fields exposed workers]. / Implicazioni per la tutela della salute dei lavoratori esposti ai campi elettromagnetici.

In this paper are discussed the possible consequences of the recent classification of Radiofrequencies as Group 2B IARC, and of the revision of the European Directive 2004/40/CE currently in progress, on measures for the protection of workers exposed to electromagnetic fields in Italy. No conclusion is possible regarding the revision of 2004/40/CE, until the definitive text is approved, and implemented in Italy. Balanced information on 2B IARC classification of RF (but also of ELF) should be included in information of workers on the occupational risk; furthermore, unnecessary exposure should be avoided, and exposure minimized, as part of general measures for protection.

[Heat stroke in the workplace: description of a case with fatal outcome]. / Colpo di calore in ambito lavorativo: descrizione di un caso con esito fatale.

BACKGROUND: Heat exposure represents an occupational risk factor in various work settings. Adverse effects may range from mild symptoms, like muscular cramps, to life threatening conditions, like heat stroke. Data on the occurrence of work-related adverse effects of heat exposure in Italy are lacking. OBJECTIVES: To highlight the risk of heat stroke in a common working activity. METHODS: The case of a fatal heat stroke in a 19-year-old worker, in apparently good health, employed in maintenance of open park spaces is presented. After working 7 hours outdoors on a sunny day he was found unconscious. He was immediately taken to the local Emergency Department, where he arrived in hyperthermic and comatose conditions, and died due to multiple organ failure after 36 hours. After excluding other main causes of hyperthermia, heatstroke was identified as the initial cause of death. RESULTS: The case presented describes the possible extreme consequences of an underestimation of the risk related to occupational heat exposure, even in young and apparently healthy workers. Heat-related adverse effects may occur in a number of common activities, not necessarily involving heavy workload or extreme temperatures. Different methods, including simplified methods, are available for heat stress risk evaluation. The main preventive measures include adequate acclimatization, periodic interruption of exposure, sufficient fluid intake, adequate clothing and appropriate Personal Protective Equipment. Adequate training and workers' health surveillance are also essential. CONCLUSIONS: Heat exposure may be a significant occupational risk, potentially inducing life-threatening conditions, in a number of common activities but is frequently underestimated. An example of undervaluation of the risk and of the possible consequences, are presented and discussed in this case report.

Natural killer cell activity decreases in workers occupationally exposed to extremely low frequency magnetic fields exceeding 1 microT.

In a preliminary study a reduction in natural killer (NK) cell activity in peripheral blood lymphocytes (PBL) was observed in a group of workers exposed to levels of extremely low frequency-magnetic fields (ELF-MF) exceeding 1 microT. This study was performed to confirm the results. In 121 workers engaged in various occupational activities, individual ELF-MF exposure was monitored for 2 work shifts. Exposure levels were calculated as time-weighted average (TWA). Subjects were classified as Low exposure (TWA < or = 0.2 microT), Medium exposure (TWA 0.21-0.99 microT), or Higher exposure (TWA > or = 1 microT). In higher exposure workers NK activity proved significantly reduced compared to low exposure,(p<0.01). In medium exposure a reduction was also observed, but the difference was not significant. Multivariate analysis also confirmed the relation between exposure and NK activity. It has been suggested that ELF might affect tumour progression by inducing changes in the immune system: due to the role played by NK activity in host defence against cancer, the interference with the NK cell activity observed in this study is in agreement with this hypothesis. Furthermore, an increased risk for some neurodegenerative disorders has been reported in some epidemiological studies in ELF-MF-exposed workers: changes in NK function were also described in these diseases. Our results, showing the effect on NK activity of exposure exceeding 1 microT, suggest a possible mechanism for ELF-MF effects. This could open new horizons regarding the adverse long-term effects of these fields.

[Italian translation and validation of the Nordic IRSST standardized questionnaire for the analysis of musculoskeletal symptoms]. / Traduzione in lingua italiana e validazione del questionario standardizzato Nordic IRSST per la rilevazione di disturbi muscoloscheletrici.

BACKGROUND: Data on self-reported symptoms and/or functional impairments are important in research on work-related musculoskeletal disorders (WRMSDs). In such cases the availability of international standardized questionnaires is extremely important since they permit comparison of studies performed in different Countries. OBJECTIVES: Translation into Italian and validation of the Nordic Musculoskeletal Questionnaire (NMQ), a tool which is widely used in studies on WRMSDs in the international scientific literature. METHODS: The extended Canadian version of the NMQ was translated into Italian. As per the current guidelines, the cross-cultural adaptation was performed by translation of the items from French, back-translation by independent mother-tongue translators and committee review. The resulting version of the questionnaire underwent pre-testing in 3 independent groups of subjects. The comprehensibility, reliability (internal consistency and reproducibility) and sensitivity were evaluated. RESULTS: After translation/back-translation and review of the items the comprehensibility of the Italian version of the questionnaire was judged good in a group of 40 workers. The internal consistency was evaluated using the Cronbach's Alpha test in the same group and in another 98 engineering workers: the results were on the whole acceptable. The reproducibility, which was tested with Cohen's Kappa test in the 40 workers, was good/excellent. In a preliminary evaluation, performed in 30 outpatients of a of Rehabilitation Service, sensitivity was very good. CONCLUSIONS: The results show that the Italian version of the Nordic Musculoskeletal Questionnaire is valid for self-administration and can be applied in 'field" studies on self-reported musculoskeletal symptoms and functional impairments in group of workers.

[Evaluation of the genotoxicity of the extremely low frequency-magnetic fields (ELF-MF) in workers exposed for professional reasons]. / Valutazione della genotossicità dei campi magnetici a frequenza estremamente bassa (ELF-MF) in lavoratori esposti per ragioni professionali.

Whether 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.

[ELF-MF occupational exposure: repeated measures on workers]. / Campi magnetici ELF ed esposizione professionale: misure ripetute della esposizione individuale in lavoratori addetti a varie mansioni.

The 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.

[The Italian version of Nordic Musculoskeletal Standardized Questionnaire]. / Versione in lingua Italiana del questionario standardizzato autocompilabile Nordic IRSST per la rile vazione di disturbi muscoloscheletrici .

We translated into Italian the Nordic musculoskelethal questionnaire, as completed by Canadian IRSST with Authors' agreement in 2001, according to OMS recommendations. This translation involved the following items: aches and troubles of neck, dorsal region, low back, shoulders, elbows, hands and wrists, hips and thighs, ankles and feet in the last 12 months. The questionnaire was then submitted to reliability and stability tests. The Italian version of the questionnaire, already used in different languages, proved to be suitable and reliable also for self administration.

[Evaluation of the occupational risk related to exposure to electromagnetic fields according to the EC Directive 2004/40 EC: exposure during pregnancy]. / La valutazione del rischio da campi elettromagnetici al sensi della Direttiva Comunitaria 2004/40 CE: esposizione professionale in corso di gravidanza.

The EU Directive 2004/40/EC on the minimum health and safety requirements regarding the exposure of workers to the risks arising from physical agents (electromagnetic fields) will introduce the need of an evaluation of the risk related to EMF occupational exposure in pregnancy. Nevertheless, data from research in this field are scarcely conclusive to date. Furthermore knowledge on this risk seems insufficient among OH physicians in Italy. Accordingly, there is an urgent need for further research, and for a diffusion of knowledge among OH physicians on possible risk to pregnancy due to occupational exposure to EMF.

[Assessment of the risk of occupational biomechanical overload: comparison of methods currently used]. / La valutazione del rischio da sovraccarico biomeccanico occupazionale: confronto tra metodi di corrente utilizzo.

Some of the most common methods for the evaluation of the ergonomic risk of Work-Related Musculo Skeletal Disorders were applied to different workplaces. The results show that an evaluation of the single components of the synthetic risk-indices given by the methods is needed to evidence the specific critical aspects.

[Personal exposure to ELF magnetic fields in workers engaged in various occupations]. / Esposizione personale a campi magnetici a frequenza estremamente bassa in lavoratori addetti a varie mansioni.

Using 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.

[Occupational exposure to 50 Hz magnetic fields in workers employed in various jobs]. / Esposizione professionale a campi magnetici a 50 Hz in lavoratori addetti a varie mansioni.

BACKGROUND: Information on occupational exposure to ELF magnetic fields (MF) in workers is largely insufficient, and is mostly based on results obtained in Scandinavian countries and North America. Accordingly, the collection of further data is needed, especially in workers exposed in other countries, including in Italy. METHODS: One hundred and fifty workers (84 males and 66 females) employed in 28 different jobs in the Emilia-Romagna Region of Italy were examined. Individual exposure was measured using personal monitors worn on the hip in a belted pouch during three whole work-shifts (8 hours each) of a normal working week. A sampling interval of 10 seconds was adopted, resulting in the collection of more than 8600 measurements for each worker. The individual Time-Weighted Average (TWA) occupational exposure of workers was calculated as the arithmetic mean of all measurements during each work-shift. Environmental non-occupational exposure was also measured. RESULTS: The 50 degrees percentile of individual TWA in the whole group was 0.15 microT, and the 5 degrees - 95 degrees percentile was respectively 0.02-1.45 microT. Job-related exposure (expressed as the mean of the TWA measured in all workers engaged in that job) was highest in substation electric power plant workers (1.12 microT) and in sewing machine workers (0.84 microT), but was lower than 0.2 microT in more than the 70% of the examined jobs. Considering the geometric mean of individual TWA are 27 out of 28 the jobs inducing an exposure lower than 0.2 microT. The lowest exposure was observed in infant school teachers. A high variability was observed among different workers engaged in the same occupation, mainly in substation electric power plant workers, machine testers and grinders in the engineering industry and in sewing machine workers and quality control in garment production. A marked variability of the pattern of exposure during the work-shift was also observed The overall environmental (non-occupational) exposure was 0.044 microT, and individual exposure was lower than 0.2 microT in about 97% of the examined subjects. Occupational exposure was usually higher and was not correlated with environmental exposure. CONCLUSIONS: The results show that the occupational component of overall exposure must be considered in studies on the biological effects of ELF-MF in populations. The high variability observed among workers engaged in the same occupation and the variability of the pattern of exposure certainly constitute major problems and could be a cause of the scarce coherence of the results of epidemiological studies on biological effects of ELF-MF to date. An improvement in protocols for the evaluation of exposure in workers, including the use of personal monitoring, is certainly needed.

[Sister chromatid exchange (SCE)and high-frequency cells in workers professionally exposed to extremely low-frequency magnetic fields (ELF)]. / Scambi tra cromatidi fratelli (SCE) e high-frequency cells in lavoratori professionalmente esposti a campi magnetici a frequenza estremamente bassa (ELF).

BACKGROUND: Up now no firm conclusions can be drawn on the genotoxicity of Extremely Low Frequency (ELF) Magnetic Fields (MF) in exposed workers: both an increase in chromosomal aberrations (CA) and micronuclei (MN) or no effects were observed in substation workers, while a slight increase in CA, but not in sister chromatid exchanges (SCE) or MN was reported in linesman; an increase in CA was observed in cable splicers and, more recently, in train engine drivers, but results have not been replicated. OBJECTIVES: Objective of the study was an evaluation of possible genotoxicity of occupational exposure to ELF-MF. METHODS: SCE, high-frequency cells (HFC) and SCE in HFC were measured in peripheral blood lymphocytes from 70 workers exposed to various levels of ELF-MF in different occupations, not involving exposure to known mutagens or carcinogens. In all participants, individual ELF-MF exposure was measured throughout the whole work-shift for 3 consecutive days by personal monitoring. RESULTS: Time Weighted Average (TWA) values of ELF-MF in the whole group ranged from 0.01 to 3.48 microT; the geometric mean was 0.19 mT, and only 3 subjects exceeded 2 microT. According to the individual TWA exposure, subjects were divided into two groups: low exposed (< or = 0.2 microT) and highly exposed (> 0.2 microT). The mean values of SCE, HFC and SCE in HFC were compared between low and highly exposed: no significant differences were observed. The result was further tested by selection and comparison of workers exposed up to 0.1 microT vs. exposed > 0.4 microT only, i.e. excluding intermediate exposures: again no difference in genotoxicity indices was observed. Also multivariate analysis did not show any correlation between individual ELF-MF exposure and genotoxicity indices. CONCLUSIONS: The results of our study do not give any support to the hypothesis that occupational exposure to ELF-MF up to about 2 microT, i.e. at the levels currently found in most workplaces, can exert a genotoxic effect in workers.