When cesium is absorbed by the body, it is excreted in a relatively short time—approximately one year. Strontium, on the other hand, is quickly absorbed by a growing embryo, fetus, and child, and is bound to structures that normally bind calcium, such as bone and teeth, where it can remain for a lifetime.
We determined that an average pregnant woman in Polissia ingests 268 becquerels daily, which is above the upper daily limit of 210 becquerels set for adults by the Soviet Union. The cumulative upper total body count of becquerels for adults was set at 14,800 and for individuals under fifteen was set at 3,700. It is well established that growing organisms are more sensitive to ionizing radiation damage. The upper limit for the rapidly developing human embryo-fetus has yet to be determined.
To simplify the process of estimating radiation exposure and to enhance the accuracy of the estimates, we opted to directly measure whole-body counts of becquerels, which reflect the quantity of cesium-137 incorporated by pregnant women. (Detecting strontium is much harder.) The whole-body count of cesium-137 incorporated by 48 percent of 1,156 pregnant women in Distant Polissia (the three counties farthest north) was above the 3,700-becquerel limit set for individuals under fifteen. Among 6,026 pregnant women investigated, only those from Polissia accumulated significant levels of cesium-137.
The most significant negative impact of radiation on a developing embryo includes anencephaly, which is a developmental deficiency in the skull and in the brain, and microcephaly, which, according to our strict definition, is a reduction in head circumference of three standard deviations below the norm. We found that the frequency of microcephaly was statistically significantly higher in Polissia. We measured the head circumferences of all newborns at birth in one county in Polissia as well as in Rivne City outside Polissia. The head circumferences of the newborns in Polissia were statistically significantly smaller than in Rivne City. We then measured the head circumferences of newborns in another Polissia county and compared these with the head circumferences measured in every county outside Polissia. The results again indicated that head circumferences were statistically significantly reduced in Polissia.
A teratogen is any environmental factor that can cause malformations or developmental alterations. In Ukraine, common teratogens are radiation and alcohol. Both can cause similar congenital anomalies, such as severe or minimal microcephaly. Our program studied not only radiation but also alcohol teratogenicity, partnering with the Collaborative Initiative on Fetal Alcohol Spectrum Disorders (CIFASD), which monitored alcohol use in pregnant women in Rivne and assessed its potential developmental impact on their children. We concluded that alcohol was not a likely cause of higher rates of microcephaly or reduced at-birth head circumferences in Polissia. An analysis of alcohol use by pregnant women clearly shows that alcohol consumption in Polissia is statistically significantly less frequent than outside Polissia.
The range of human congenital anomalies is vast. In Rivne, the rates of sentinel anomalies, such as Down syndrome and cleft lip (with or without associated cleft palate), are well established. The rates of these anomalies in Polissia are similar to the rest of Rivne and to those reported across Europe. On the other hand, the rates of conjoined twins, teratomas, and neural tube defects are elevated in Rivne and even more so in Polissia. The rates of these anomalies in Polissia are among the highest in Europe. Many experts believe that the anomalies are blastopathies, which are anomalies evident in a fertilized ovum (blastula) before it develops into an embryo and it implants in the womb. Recent studies in molecular embryology suggest that any factors that delay the development of a fertilized egg—for instance, radiation damage—may result in the duplication of the axis of an embryo, causing twinning or other blastopathies such as anencephaly. Recent studies also show that female embryos reach developmental stages at a slower pace, which may render them more vulnerable to the kind of blastopathies observed in Rivne.
The Chornobyl accident turned into a catastrophic disaster in great part because of the inadequate response by the Soviet authorities and their chosen experts. These experts, for example, claimed that people in Ukraine who were impacted by the radiation suffered merely from radiophobia—an abnormal fear of ionizing radiation. Yet evidence of the profound impact of the Chornobyl disaster on Ukrainians can be found in the dramatic drop in the birthrate, which persists even now. The Soviet Union ignored the severe impact of radiation pollution on the population in Polissia—a mistake corrected only in 1991 after Ukraine became independent.
We are aware that reports of elevated rates of congenital anomalies in regions impacted by radiation from Chornobyl are greeted with skepticism and often dismissed. There are many reasons for this, among them the persistent denials by organizations such as the International Atomic Energy Agency (IAEA), the World Health Organization (WHO), and the United Nations Development Programme (UNDP). The IAEA asserts that “because of the relatively low doses to residents of contaminated territories, [there is] no evidence or likelihood of decreased fertility… no evidence of any effect on the number of stillbirths, adverse pregnancy outcomes, delivery complications or overall health of children…. A modest but steady increase in reported congenital malformations… appears related to better reporting, not radiation.”
This assertion is not based on actual investigations in areas impacted by Chornobyl but mostly on the results of previous investigations in Hiroshima and Nagasaki, which were sponsored by the Atomic Bomb Casualty Commission (ABCC). A critical difference between the Hiroshima-Nagasaki and Chornobyl radiation impacts is that radiation exposure from the atomic bombs was external, intense, and short. There was virtually no residual radiation. In contrast, the radiation exposure from Chornobyl was internal, low, and continuous. The impact of radiation on health is cumulative. The average pregnant woman in Polissia absorbs at least 250 becquerels per day, which by the age of twenty-five is equivalent to over 2,200,000 becquerels. A growing number of parents have been exposed to radiation since their own conception.
For the most part, ABCC-sponsored studies were performed before the establishment of the American and later Japanese and European teratology societies, which developed the current criteria for scientific investigations into the human environmental causes of congenital malformations. Launched nearly five years after the bomb blasts, the studies were not based on the exposed population. They were based on children who had not been exposed to radiation but whose parents had been irradiated by the blasts and had survived the explosions and famine that followed.