How radiation affected the Ukrainian gene pool
Medical research shows that the incidence of diseases among children has doubled, and infertility among women has become more prevalent
The Chornobyl accident is now a hot topic, even more so than ever before. This is so not just because we will soon commemorate the 25th anniversary of the tragedy, but also because a similar disaster in Japan is now making itself felt all over the world. The explosions at the Fukushima 1 nuclear reactor have already been dubbed a “second Chornobyl,” and this comparison implies consequences for human health, too. Recently, an international conference “25 Years after the Chornobyl Disaster: Implications for Health and Ecology” was held in Berlin. It was attended by doctors and biologists from Germany, Ukraine, Russia, the United Kingdom, Switzerland and Japan. The experts’ attention was turned to the impact of the Chornobyl accident on people’s health and the lessons Japan could learn from this experience. The results of medical studies conducted by Ukrainian scientists from the Academy of Medical Sciences are seen as particularly relevant here, since they studied the health of women and children starting from the first day of the Chornobyl disaster. Although the data was not presented at the Berlin conference, the Ukrainian specialists are ready to share these results any time.
At the time of the Chornobyl accident, 501 pregnant women were registered as living in the 30-kilometer exclusion zone. Back then there were no radiation centers in Ukraine, so women from this region gave birth at the Institute of Pediatrics, Obstetrics and Gynecology. Since then, its staff has monitored the women and their children.
Experts have concluded that radioactive contamination had the strongest effect on the female reproductive function. The number of births in Ukraine has decreased by 40 percent (compared with data for 1986), with frequent cases of infertility due to increased prevalence of genital inflammation. However, doctors say the causes of infertility for many couples include not only the Chornobyl disaster, but also the environmental and socio-economic conditions.
“We also have recorded an increased number of cases of various complications during pregnancy and childbirth in women who lived in areas under a radiation control regime,” says Director of the Academy of Medical Sciences’ Institute of Pediatrics, Obstetrics and Gynecology Yurii Antypkin. “A significant number of spontaneous abortions and miscarriages were observed in women living in areas with the highest level of radionuclide contamination (the so-called second zone). The spike in such cases was recorded in the second and third year after the accident. The number of complications during pregnancy was significantly higher than that in women not exposed to radionuclides. The reason is that the placenta, where the child grows while still in the womb, also accumulates radionuclides and transfers them from the mother’s body to the fetus. This is undesirable, because the child must develop in the womb without harmful influences. But it happened so that the radionuclides were transported into the fetus’s little organs, and this led to development of placental deficiency or placental dysfunction syndrome during pregnancy. The aggregate effect of all this were cases of intrauterine death of the fetus.”
The echo of Chornobyl is still felt today, especially among those women who live in contaminated areas. According to the doctors, it primarily relates to the increased number of pregnant women with thyroid diseases. According to Yulia Davydova, doctor and research fellow at the institute, to prevent this, pregnant women of Ukraine’s seven iodine-deficient regions are prescribed iodine drugs, such as iodomarin, or vitamin-mineral complex with adequate iodine content, and doctors advise them to stick to seafood-heavy diets.
The doctors are concerned that thyroid diseases have also affected children. Prevalence of malignant neoplasms increased sharply after the disaster: while Ukrainians had heard predictions of an increase in thyroid cancer coming after the eighth year of tragedy, Ukraine was already experiencing this increase in the fourth year after the accident. “The Institute of Endocrinology monitors the category of under-18-year-olds suffering from thyroid cancer. Currently, the registry includes about 6,000 people. By the way of comparison, until 1986, thyroid cancer was rarely diagnosed in children and adolescents,” Davydova explains. “It is dangerous because the more the child was exposed to radioactive iodine, the more it suffers from somatic diseases, because its endocrine and immune systems are compromised. Since these systems are responsible for the resistance and security of the child’s entire body, other diseases become more prevalent against this background, too.”
How many more people may be afflicted with thyroid diseases, in what direction will the situation in Ukraine develop, will the number of cases increase or decrease — all these questions are yet to be answered. Right now scientists are developing forecasts on the trends in this field.
The doctors also stress the importance of another pathology, namely damage to the immune system. “Children who were exposed to radiation and then removed from the 30-kilometer zone (now they are adults), and children who are born and live in radiation-contaminated areas, are more prone to infectious diseases,” Antypkin continues. “Although these illnesses are not major, still, their share has increased. I mean acute respiratory diseases, digestive system disorders, cardiovascular system diseases... and this group of children suffers from various complications after contracting these infectious diseases. Before the Chornobyl disaster, we recorded 500-600 diseases per 1,000 children, while today the number has doubled, and a child may have two or three diseases simultaneously.”
On the bright side the studies reveal that the Chornobyl accident did not increase the number of hematological malignancies. “Today, the prevalence of cancer in children is no higher than it was before. The only change is that leukemia cases have been redistributed. Previously, it affected mostly children under 12 years, while now, 12-year-old and older children are most endangered. Fortunately, there was no growth of hematological diseases,” the director says. “Immediately after the accident, we were worried about inherited mutations that could affect the children of the liquidators. Again, fortunately, the number of inherited mutations has not increased. But if these children are divided into groups depending on when they were conceived, we see the following pattern: if the parents conceived the child during the first month after the father stopped working as a liquidator, then these children are at almost twice the risk of inherited mutations, compared to the national average. That is, radiation’s effect on mature male sex cells is the strongest in the first month after exposure. Later on, this effect levels off. There can be various mutations at the genetic level, but we are speaking now about those that can be transmitted from generation to generation. What they will bring in terms of health status, only time will tell.”
This survey’s results show that the Chornobyl disaster influenced the health of the Ukrainian people in one way or another. Although the accident is now a quarter-century old, experts say that only the health consequences are obvious as of today. What other sinister surprises will the April 1986 event bring to us, doctors still do not know.
