Static magnetic field measurements in residences in relation to resonance hypotheses of interactions between power‐frequency magnetic fields and humans

Abstract

Bowman et al. used epidemiologic data to test a model in which subjects were classified as being "in-resonance" or "not-in-resonance" for 60-Hz magnetic-field exposures depending on single static magnetic-field measurements at the centers of their bedrooms. A second paper by Swanson concluded that a single static magnetic-field measurement is insufficient to meaningfully characterize a residential environment. The main objective of this study was to investigate exposure-related questions raised by these two papers in two U.S. data sets, one containing single spot measurements of static magnetic fields at two locations in homes located in eight states, and the other repeated spot measurements (seven times during the course of one year) of the static magnetic fields at the centers of bedrooms and family rooms and on the surfaces of beds in 51 single-family homes in two metropolitan areas. Using Bowman's criterion, bedrooms were first classified as being in-resonance or not-in-resonance based on the average of repeated measurements of the static magnetic field measured on the bed where the presumed important exposure actually occurred. Bedrooms were then classified a second time using single spot measurements taken at the centers of bedrooms, centers of family rooms, or on the surfaces of beds, as would be done in the typical epidemiologic study. The kappa statistics characterizing the degree of concordance between the first (on-bed averages) and second (spot measurements) methods of assessing resonance status were 0.44, 0.33, and 0.67, respectively. This level of misclassification could significantly affect the results of studies involving the determination of resonance status.

Could Magnetic Fields Affect the Circadian Clock Function of Cryptochromes? Testing the Basic Premise of the Cryptochrome Hypothesis (ELF Magnetic Fields)

“…Induced magnetization in steel (μr ∼ 2,000) indeed locally modifies Earth's MF intensity (decrease of the perturbation in 1/R 3 ). Near common large artifacts (radiator, steel beam), variations of Earth's MF intensity can reach ± 50% (Kaune et al 2001). In the case that such intensity changes affect the CRY clock function, they would thus constitute a confounder factor under the CRY hypothesis.…”

Study of high‐ and low‐current‐configuration homes from the 1988 Denver childhood cancer study

“…This means that a static magnetic ®eld measurement made in one room in a home does not characterize to a high degree the static magnetic ®eld in any other room in the house. Low correlations between static ®elds measured in different rooms have also been observed by Swanson [1994] and Kaune et al [2001].…”

“…However, in our view the likelihood that Bowman's model is correct is reduced somewhat by our failure to observe any substantial evidence of the predicted resonance effect. In addition, our as well as other's [Swanson, 1994;Kaune et al, 2001] observations of very low correlations between static magnetic ®eld measurements made in different rooms, or even at two points in the bedroom, of the same home, raise doubts about the very feasibility of testing this model using simple static magnetic ®eld measurements at a few points in homes.…”

“…Since geomagnetic ®elds are measures of the earth's magnetic ®eld with the perturbing in¯uences of local materials, e.g., steel used in the construction of buildings, removed, the BTD results suggest that Colorado residences may be slightly shielded (&3%) by their roofs, walls, and/or internal furnishings. Residential shielding has been reported in another study [Kaune et al, 2001].…”

Advances in Residential Design Related to the Influence of Geomagnetism

“…The intensity of the magnetic flux increases or decreases within local limits, and terrestrial radiation is also altered by other artificial factors related to the design and construction of buildings [ 54 ]. In turn, the general buffering effect of a resistant structure that occurs in all buildings [ 55 ] must be taken into account to adequately establish the comparison values of this study.…”