Carcinogenicity test in B6C3F1 XXXX after parental and prenatal exposure to 50 Hz magnetic fields.

@entity5 @entity19
Some epidemiological studies suggest association of @entity5 with occupational exposure of the parents to magnetic fields. To test this relationship, 50 each of C57BL/6J female and C3H/HeJ male @entity19 were exposed for 2 and 9 weeks, respectively, to 50 Hz sham (group A), 0.5 (group B), and 5 mT (group C) sinusoidal alternating magnetic fields. They were mated under the exposure for up to 2 weeks, and the exposure was continued until parturition. All the B6C3F1 offspring, without adjusting numbers of animals, were clinically observed without exposure to magnetic field for a nominal 78 weeks from 6-8 weeks of age after weaning and then euthanized for pathological examination according to a routine carcinogenicity test. 540 pups entered the test, and the survival rate was 96.7%. No F1 @entity19 died of @entity5 before a male in A group died of @entity5 at 43 weeks of age. The first animal death in the exposed groups due to @entity5 occurred at 71 weeks of age. Eighteen animals died before necropsy at 84-86 weeks of age. No significant difference was detected in the final number of survivors and incidence of @entity5 between groups A and B, or A and C. Concerning reproduction total implants in group B were less than in group A and the difference was on the borderline of significance (P=.05). This difference was not reproduced in a later duplicate experiment.
