Electromagnetic fields and breast cancer on Long Island: a case-control study.

The EMF and Breast Cancer on Long Island Study (EBCLIS) was a case-control study designed to evaluate the possible association between exposure to electromagnetic fields (EMFs) and breast cancer. Eligible women were participants in the population-based Long Island Breast Cancer Study Project, were under 75 years of age at enrollment, were residentially stable, and were identified between August 1, 1996, and June 20, 1997. Of those eligible, 576 cases and 585 controls participated in EBCLIS (87% and 83%, respectively). In-home data collection included various spot and 24-hour EMF measurements, ground-current magnetic field measurements, wire mapping of overhead power lines servicing the home, and an interview. Odds ratios and 95% confidence intervals were based on multivariate logistic regression analyses. All odds ratios were close to 1 and nonsignificant. For the highest quartile of 24-hour EMF measurements, the odds ratio was 0.97 (95% confidence interval (CI): 0.69, 1.37) in the bedroom and 1.09 (95% CI: 0.78, 1.51) in the most lived-in room. For the highest exposure category of ground-current measurements, the odds ratio was 1.13 (95% CI: 0.88, 1.44) in the bedroom and 1.08 (95% CI: 0.85, 1.38) in the most lived-in room. These and other EBCLIS results agree with other recent reports of no association between breast cancer and residential EMF exposures.

Breast cancer and electromagnetic fields--a review.

PURPOSE: Several statements have been issued to the effect that no consistent, significant link has been demonstrated between cancer and electromagnetic fields (EMF). However, there continues to be much interest in a possible association with breast cancer, in part because breast cancer risk is substantially higher in industrialized countries than in other areas, and electric power generation and consumption is one of the hallmarks of industrialized societies. In 1987, Stevens proposed a biological mechanism whereby two products of electric power generation, EMF and light at night, might contribute to mammary carcinogenesis through inhibition of melatonin. METHODS: We conducted a comprehensive review of the epidemiologic literature and hypothesized mechanisms pertaining to EMF exposure and the risk of breast cancer, in order to assess whether or not there was evidence to suggest a link between EMF and breast cancer. RESULTS: Some occupational epidemiological studies have demonstrated an increased incidence of breast cancer among mainly male electrical workers. It has been difficult to study women, as few are employed in these types of occupations. In all, there have been eleven occupational studies related to breast cancer in women, and statistically significant risk ratios have been observed: 1.98 for pre-menopausal women in occupations with high EMF exposure in one study, 2.17 in all women who worked as telephone installers, repairers, and line workers in another study, and 1.65 for system analysts/ programmers, 1.40 for telegraph and radio operators, and 1.27 for telephone operators in a third study. However, six of the studies did not find any significant effects and two found effects only in subgroups. The results of the eight studies of residential exposure and four electric blanket studies have been inconsistent, with most not demonstrating any significant association. However, this might be attributed, at least to some extent, to difficulties in assessing residential exposure in these studies, as well as other methodological considerations. CONCLUSIONS: The biologic plausibility of an association between EMF and breast cancer, coupled with suggestive data from occupational studies and unexplained high incidence rates of breast cancer, suggests that further investigation of this possible association is warranted.

Social network disturbances and psychological distress following earthquake evacuation.

The relationship between social network disturbances following earthquake evacuation and self-reported psychological distress (reduced version of the SCL-90-R) 3 to 4 years later was studied among 817 Italian male factory workers. Increased distress was reported by permanently relocated men, while those who were evacuated, but returned to their original homes, reported distress levels comparable to their nonevacuated co-workers. Additionally, among evacuated men, only those whose relocation placed them at an increased distance from family and/or friends reported distress levels higher than the nonevacuated. Change in visiting frequency with family and/or friends following evacuation was not related to distress. Although these data are correlational and cross-sectional, they are consistent with the hypothesis that disaster related distress is, in part, a function of resulting social network disruption.

Long-term psychological effects of natural disasters.

Relationships between self-reported psychological distress (Symptom Checklist) and experience with two earthquakes are presented for a group of male factor workers (N = 772) from Naples, Italy, participating in the 1987 follow-up of the Olivetti Heart Study. Although all were exposed to the 1980 earthquake that racked southern Italy, only men residing in the Naples suburb of Pozzuoli experienced the continuing swarm of earthquakes ("bradyseism") of 1983-1984, allowing for the observation of a "natural experiment" of sorts. Levels of psychological distress were found to be higher 7 years after the first earthquake for those men who reported damage from that earthquake. Overall, findings were similar for those who were evacuated, or suffered financial loss from the 1983-1984 bradyseism earthquakes. Stratification by 1980 earthquake damage revealed that 1983-1984 evacuation or financial loss was associated with increased distress reporting only for those men who had not reported damage from the 1980 earthquake. Overall, however, distress scores tended to be higher for men evacuated in 1983-1984 if they had also reported damage from the prior earthquake (only the F ratio for anxiety reached criterion for statistical significance). These findings suggest that the psychological consequences of earthquake exposure are long lasting and seem to be related to the consequences of the earthquake in terms of damage/loss.