Chick Embryo Development Can Be Irreversibly Altered by Early Exposure to Weak Extremely-Low-Frequency Magnetic Fields

Bioelectromagnetics. 1994;15(5):385-98. doi: 10.1002/bem.2250150503.

Abstract

Several reports have shown that weak, extremely-low-frequency (ELF), pulsed magnetic fields (PMFs) can adversely affect the early embryonic development of the chick. In this study, freshly fertilized chicken eggs were exposed during the first 48 h of postlaying incubation to PMFs with 100 Hz repetition rate, 1.0 microT peak-to-peak amplitude, and 500 microseconds pulse duration. Two different pulse waveforms were used, having rise and fall times of 85 microseconds (PMF-A) or 2.1 microseconds (PMF-B). It has been reported that, with 2 day exposure, these fields significantly increase the proportion of developmental abnormalities. In the present study, following exposure, the eggs were allowed to incubate for an additional 9 days in the absence of the PMFs. The embryos were taken out of the eggs and studied blind. Each of the two PMF-exposed groups showed an excess in the percentage of developmental anomalies compared with the respective sham-exposed samples. This excess of anomalies was not significant for the PMF-A-treated embryos (P = 0.173), whereas it was significant for the PMF-B-exposed group (P = 0.007), which showed a particularly high rate of early embryonic death. These results reveal that PMFs can induce irreversible developmental alterations and confirm that the pulse waveform can be a determinant factor in the embryonic response to ELF magnetic fields. The data also validate previous work based on the study of PMFs' effects at day 2 of embryonic development under field exposure.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abnormalities, Radiation-Induced / etiology*
  • Animals
  • Bone and Bones / abnormalities
  • Bone and Bones / embryology
  • Bone and Bones / radiation effects
  • Chick Embryo
  • Congenital Abnormalities / etiology*
  • Death
  • Electromagnetic Fields / adverse effects*
  • Hot Temperature
  • Magnetics / adverse effects*
  • Magnetics / classification
  • Reproducibility of Results
  • Single-Blind Method
  • Time Factors