Evaluation of the Developmental Toxicity of 60 Hz Magnetic Fields and Harmonic Frequencies in Sprague-Dawley Rats

Abstract Ryan, B. M., Polen, M., Gauger, J. R., Mallett, B., Jr., Kearns, M. E., Bryan, T. E. and McCormick, D. L. Evaluation of the Developmental Toxicity of 60 Hz Magnetic Fields and Harmonic Frequencies in Sprague-Dawley Rats. Experimental data suggest that exposure to the 50 and 60 Hz sinusoidal components of power-frequency magnetic fields (MFs) does not have an adverse impact on fetal development. However, the possible developmental toxicity of MF harmonics has not been investigated. This study was designed to determine whether exposure to 180 Hz MFs (third harmonic), alone or in combination with 60 Hz MFs, induces birth defects in Sprague-Dawley rats. Groups of sperm-positive dams (≥20/group) were exposed for 18.5 h per day from gestation days 6 through 19 to (1) ambient MFs only (<0.0001 mT; sham controls); (2) 60 Hz MFs at 0.2 mT; (3) 180 Hz MFs at 0.2 mT; or (4) 60 Hz + 180 Hz MFs (10% third harmonic; total field strength = 0.2 mT). Litter size, litter weight, percentage live births, sex ratio, ...