Anencephalus, drinking water, geomagnetism and cosmic radiation.
Am J Epidemiol 1979; 109(1):88-97
The rates of anencephalus in 36 Canadian cities and the province of New Brunswick from 1950 through 1969 were reviewed with regard to the horizontal geomagnetic flux, city growth, and the magnesium (7439954) concentration of tap water. High geomagnetic flux was considered as inversely related to levels of cosmic radiation. Data were screened by a bipartite stratification of the variables for associations with anencephalus. Preliminary screening indicated an association between mortality rates due to anencephaly and city growth factors, geomagnetic flux, and water magnesium levels. Statistical analysis indicated a linear relationship between anencephaly and the horizontal geomagnetic flux in the presence of low city growth rates, with an inverse relationship between city growth rate and anencephaly that was independent of the geomagnetic flux. City size alone was not related to incidence of deaths from anencephaly. The relationship between cosmic radiation and geomagnetic flux was discussed in terms of possible genetic effects which could be related to anencephaly. The authors conclude that background radiation has biological effects on human life.
Environmental-health-monitoring; Water-analysis; Central-nervous-system; Neuropathology; Toxic-effects; Developmental-disorders; Geophysics; Ionizing-radiation; Environmental-contamination; Physiological-response; Exposure-levels
American Journal of Epidemiology