Radiocesium and congenital malformations
Y.I. Bandazhevsky
"Health effects of the Chernobyl accident : results of 15-years follow-up studies",
Abstract submitted for the plenary session, Wednesday, June 6th, 2001
"Genetic consequences of the Chernobyl accident"
After Chernobyl, the incidence
of congenital malformations increased : those of the central nervous system, the
heart, the face, the limbs and the fingers increased in Belarus. This increase
was significantly higher in more than in less contaminated zones (Botshkov et
al. 1996).
Clinical and experimental work performed by research teams at the Medical
Institute in Gomel, showed the negative impact of even low levels of
incorporated Cs137 on the human organism : Levels of Cs137 above 50 Bq/kg
body-weight impair the cellular metabolism, especially the synthesis of
proteins. This occurs also during pregnancy, with high levels of incorporated
CS137 in the maternal organism.
Fetuses with central nervous system malformations show higher average levels of
Cs137 in the placenta compared with fetuses with other deformities.
Levels of CS137 superior to 200 Bq/kg Body-weight induce hormonal disorders in
mother and fetus, with imbalances of the thyroid, the sexual and adrenal
hormones : the cortisone values triple.
To complement these findings, laboratory experiments were conducted in pregnant
Syrian hamsters, a species with a short gestation period. The hamster genome has
similarities with that of human. It has also a predisposition to multifactorial
congenital malformations.
Method
1 ml of pure Cs137 solution (100 Bq/ml) was injected intraperitoneally on days 6
and 8 of the pregnancy.
The control group received likewise 1 ml of physiological saline solution.
Results
On day 10, the average Cs137 level was of 246(+-20.1) Bq/kg body-weight in the
treated females, compared with 12.4(+-1.7) Bq/kg in the controls. The cereals of
the standard feed is not totally free of Cs137 in Gomel.
Fetuses were examined for congenital deformities on day 15, i.e. shortly before
birth.
Cs137 levels of more than 200 Bq/kg body-weight in females induce either
teratogenic or even embryolethal effects (death of all fetuses of a female).
59% of the surviving fetuses in the Cs137 treated group show malformations of
multifactorial origin, compared with 20% in the control group, which shows in no
case any total embryolethal effect at all.
These differences are statistically significant.
Our results show the role played by Cs137 in the pathogenesis of congenital
malformations, in the presence of a genetic predisposition.
Source W.T.