NO INDUCTION OF CHROMOSOME-ABERRATIONS IN HUMAN SPERMATOZOA EXPOSED TO EXTREMELY-LOW-FREQUENCY ELECTROMAGNETIC-FIELDS

Clastogenic effects of extremely low frequency electromagnetic fields (ELF-EMFs) on human sperm chromosomes were studied using an interspeci fic in vitro fertilization system with zona-free golden hamster oocyte s. Semen samples from healthy men were exposed to ELF-EMFs (50 Hz, 20 mT) for 2 h at 37 degrees C under 5% CO2 in air. The samples were then cryopreserved in liquid nitrogen for shipment to a cytogenetic labora tory. After thawing the samples, motile spermatozoa were collected usi ng a continuous Percoll density gradient centrifugation and then capac itated for in vitro fertilization with hamster oocytes, Sperm-derived chromosomes were analyzed at first cleavage metaphase, The present exp eriment was performed twice using semen samples from two different don ors. In test-1, incidence of spermatozoa that displayed structural chr omosome aberrations was 17.0% (35/206) in the exposed group and 20.8% (55/264) in the control group. In test-2, structural chromosome aberra tions were observed in 11.1% (13/117) of exposed spermatozoa and 13.8% (13/94) of spermatozoa in the control group. In both tests, then was no significant difference in the incidence of chromosomally abnormal s permatozoa between the exposed group and the control group. Types of a berrations observed and their incidences per spermatozoon in the expos ed group were similar to those of the control group. Despite the small sample size, the present results suggest that ELF-EMFs have no clasto genic effect on human sperm chromosomes. (C) 1998 Elsevier Science B.V . All rights reserved.