Electrical wiring configurations and childhood leukemia in Rhode Island

The study of the relationship between childhood leukemia and electric power line configurations in the greater Denver, Colorado, area by Wertheimer and Leeper (Am J Epidemiol 109:273-284, 1979) was repeated in Rhode Island, focusing on leukemia (age at onset, 0-20 years; year of onset, 1964-1978). The addresses of 119 leukemia patients and 240 controls were studied by mapping power lines within 50 yards (45.72 m) of each residence. The shortest distance between each power line and the point of the residence closest to it was found; the number and types of wires in each power line were noted. Exposure weights were assigned each type of wire using Wertheimer and Leeper's median field strength reading for each. Assuming that the strength of the field decreases with the square of the distance from its source, and that fields generated by different wires grouped in the same power line are simply additive, a summary value of relative exposure was calculated for each address. Quartile exposure values for controls were used to group patient exposures. Contrary to Wertheimer and Leeper's results, no relationship was found between leukemia and electric power line configurations.