title: Intermediate frequency magnetic field and chick embryotoxicity.
abstract: Intermediate frequency magnetic fields (MFs) have widely been used in industrial machines and home appliances, such as induction heating cookers, although toxicity studies to evaluate the potential health risks of such fields are insufficient. In induction heating cookers, the MF source (i.e. hobs), is located near the abdominal position of a person cooking. Hence, developmental effects on the fetus may be a concern in case the person is a pregnant woman. Fertile White Leghorn eggs (60/group) were either exposed to 20 kHz, 1.1 mT(rms) or 60 kHz, 0.11 mT(rms) sinusoidal MFs for 19 days during embryogenesis. The same number of eggs served as a control group. In addition, a sham-sham experiment was conducted to validate the equality between exposure and control facilities. After exposure, embryos were examined for mortality rate and stage. Live embryos were evaluated for developmental stage and gross and skeletal anomalies. Length of upper beak and leg digits was also measured. Examinations were conducted in a blinded fashion to ensure quality assurance; experiments were triplicated for each frequency to confirm the outcome reproducibility. Mortality rate and stage, incidence of malformed embryos, and developmental variables in live embryos were found to be similar between the MF-exposed and corresponding control group. Incidence of gross anomalies such as mandibular edema and skeletal anomalies such as coccyx defects were low across the experiments, and no significant group differences were noted. In conclusion, exposure to 20 kHz or 60 kHz MF did not produce any significant teratogenic developmental effects in chick embryos.
authors.affiliation: Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry, Abiko, Chiba, Japan. inishi@criepi.denken.or.jp
authors.forename: Izumi
authors.initials: I
authors.lastname: Nishimura
authors.forename: Keiko
authors.initials: K
authors.lastname: Tanaka
authors.forename: Tadashi
authors.initials: T
authors.lastname: Negishi
mesh_terms: D000818:Animals; D002642:Chick Embryo; D002645:Chickens; D000013:Congenital Abnormalities / Q000209:etiology; D047108:Embryonic Development / Q000528:radiation effects*; D005313:Fetal Death / Q000209:etiology; D060526:Magnetic Fields / Q000009:adverse effects*; D013997:Time Factors
keywords: 20 kHz; 60 kHz; developmental toxicity; embryogenesis; intermediate frequency