ABSTRACT
Background: Epidemiological studies indicate increased risk of leukemia, lymphoma, and brain tumor among electrical workers exposed to electromagnetic field (EMF). Other investigator reported that continuous exposure of four successive generations of mice to EMF in doses of 1 kV to 5 kV caused tumor formation in offspring. The objective of this study was to evaluate the effect of continuous exposure of three successive generations of mice (Mus musculus L) to EMF of 3 kV, 4 kV, and 5 kV and its implication of chromosomal breakage, as detected by double minute formation. Methods: Four couples of mice of Swiss Webster strain, 3-4 months of age, and 7-40 gram of body weight were exposed to EMF at the doses of 3 kV, 4 kV, and 5 kV, and one couple served as control. Double minute formation was examined in all offspring, except one couple of each group to be exposed with the same doses of EMF to get the F2 generation, and so forth until F3 generation. Twenty metaphases of chromosomes were examined and frequencies of double minute were calculated in the three generations of all group. Results: Frequencies of double minute in F1, F2, and F3 of mice exposed to EMF of 3 kV were respectively 0.78 ± 0.08; 0.83 ± 0.09; and 0.80 ± 0.05. In the 4 kV group were 0.083 ± 0.11; 0.73 ± 0.03; and 0.96 ± 0.15, and in the 5 kV group were 0.96 ± 0.25; 0.75 ± 0.05; and 0.99 ± 0.33, whereas no double minute chromosomes were noted in control group. Frequencies of the double minute in mice exposed to EMF were significantly higher than control group. Conclusions: Continuous exposure of mice during three successive generations to EMF at doses of 3 kV, 4 kV, and 5 kV causes increased chromosomal breakage as detected as double minute chromosome formation.
Subject(s)
Electromagnetic Fields , Chromosome Breakage , MiceABSTRACT
The objective of this study is to know the biobgical effects of electromagnetic field treatment on four successive generations of mice. Fourty eight male and female mice of Swiss Webster Strain, 3 months of old, and 35 - 40 g body weight, were kept in a controlled environment and fed a standard diet. Mice were divided into 6 groups of four couples each. The first group was exposed to electromagnetic field of I kV/10 cm, the second group to 2 kV/10 cm, and the third group to 3 kV/10 cm. The remaining 3 groups were served as untreated controls of the first, second, and third group, respectively. Each couple of mice was placed in a cage (26x20x11 cm) with wire metal cage tops. The cages of experimental groups with mice inside, were then put on the negative terminal plate of a pair of parallel aluminium plate electrodes. These cages were perpendicular to the positive electrode plate at a distance of I0 cm. Subsequently, the electrodes were connected to stepup transformer as an alternating current power supply. All mice belonging to experimental and untreated control groups were allowed to mate, gastate, and deliver the first up to fourth generations, During investigation, all generations of experimental groups were continuously treated to electromagnetic field, while generations of untreated control groups received no treatment to electromagnetic field, During the study, all mice were housed in a room having a temperature of 26ᵒ C and a light - dark cycle of 12:12 hours. The results of this study showed that exposure of mice to electromagnitic field results in reduced fertility with no change in sex ratio of the offspring. Exposure to electromagnetic field, however, were effective in inducing congenital anomalies, such as micropthalmy, white eyes, short hind legs, dwarf mice, and tumors in both sexes of the offspring which caused of death after 3 - 4 months of old. A large mortality rate were found, especially in the third and fourth generations. No congenital anomalies and tumors were noted in untreated controls. ln conclusion, we suggest that several facts which found in this study were the result of changes in genetic material of the sperm or eggs during spermatogenesis or oogenesis, respectively, i.e. a mutagenic effect. This interaction between electromagnetic field and the living cell, may then cause biological effects on cells, tissues, and organs, so that finally there are consequences for the whole organisms.