CHILDHOOD EXPOSURE TO MAGNETIC-FIELDS - RESIDENTIAL AREA MEASUREMENTSCOMPARED TO PERSONAL DOSIMETRY

We examined the relation between area measurements of residential magn etic fields and personal dosimetry measurements among 64 control child ren age 2-14 years from the National Cancer Institute-Children's Cance r Group's nine state case-control study of childhood leukemia. During a typical weekday, an activity diary was completed, and a 24-hour meas urement was obtained in each child's bedroom. According to the activit y diaries, children spent more than 40% of the 24 hours in their bedro oms, and 68% of their time at home. We found that at-home personal dos imetry levels were highly correlated with total personal dosimetry lev els in children under 9 years (Spearman correlation coefficient, R = 0 .94), whereas the correlation was lower in older children (R = 0.59). For all children combined, bedroom 24-hour measurements correlated wel l with at-home personal dosimetry levels (R = 0.76). The 24-hour bedro om measurement was a useful predictor of both at-home and total person al dosimetry measurements. Particularly for younger children, our data suggest that in-home area measurements predict both current residenti al and current total magnetic field exposures. This information will b e valuable for assessing the validity of exposure assessment in previo us and ongoing studies and for developing measurement protocols for fu ture studies.