Сборник материалов международной научной конференции студентов, магистрантов, аспирантов

Я.С. Дмитрук, К.С. Савчук

Республика Беларусь, Горки, БГСХА

Научный руководитель – И.П. Макаренко

THE CONSEQUENCES OF THE CHERNOBYL ACCIDENT

On April 26, 1986 the world’s worst nuclear accident took place at the Chernobyl Nuclear Power Plant. This tragic event claimed the lives of thousands of people, brought enormous damage to the environment and, ultimately changed the course of history. Even after many years of scientific research and government investigation, there are still many unanswered questions about the Chernobyl accident – especially regarding the long-term health impacts that the massive radiation leak will have on those who were exposed.

Located about 130 km north of the city of Kiev, Ukraine, and about 20 km south of the border with Belarus, the four reactors at the Chernobyl Nuclear Power Plant were designed and built during the 1970s and 1980s. A manmade reservoir, roughly 22 square kilometers in size and fed by the Pripyat River, was created to provide cooling water for the reactor. This design is now universally recognized as inherently flawed [1].

The nearest town to the power plant was the newly built city of Pripyat, which housed almost 50,000 people in 1986. A smaller town, Chernobyl, was home to about 12,000 residents. The remainder of the region was primarily farms and woodland.

The accident occurred when operators of the power plant ran a test on an electric control system of one of the reactors. The accident happened because of a combination of basic engineering deficiencies in the reactor and faulty actions of the operators: the safety systems had been switched off, and the reactor was being operated under improper, unstable conditions, a situation which allowed an uncontrollable power surge to occur.

This led to a cascade of events resulting in a series of explosions and consequent fires that severely damaged the reactor building, completely destroyed the reactor, and caused the release of massive amounts of radioactive materials over a ten-day period.

Soviet scientists reported that the Chernobyl 4 reactor contained about 190 metric tons of uranium dioxide fuel and fission products. An estimated 13 percent to 30 percent of this escaped into the atmosphere. Contamination from the accident scattered irregularly, depending on weather conditions. Reports from Soviet and western scientists indicate that Belarus received about 60 percent of the contamination that fell on the former Soviet Union. A large area in the Russian Federation south of Bryansk also was contaminated, as were parts of northwestern Ukraine.

Since the accident, some 600 000 people have been involved in emergency, containment, cleaning, and recovery operations. Those who received the highest doses of radiation were the emergency workers and personnel that were on-site during the first days of the accident (approximately 1000 people). The area closest to the reactor site was most heavily contaminated and people who lived there were evacuated soon after the accident [2, р. 10].

After the accident, people were exposed to radiation both directly from the radioactive cloud and the radioactive materials deposited on the ground, and through consuming contaminated food or breathing contaminated air. Because of contaminated milk, the thyroids of many children were heavily exposed to radioactive iodine.

Thousands of those who were children and adolescents at the time of the accident have developed thyroid cancer as a result of exposure to radioactive iodine. The majority of those cancers have been treated successfully. Among workers who were exposed to higher dose of radiation this exposure has contributed to an increase in the number of cases of certain types of leukemia and solid cancers, and possibly of cardiovascular diseases and cataracts.

The urban areas near the reactor were heavily contaminated and rapidly evacuated. Since the accident, surface contamination has decreased and levels of radiation measured in the air are now the same as before the accident in most of these areas. But many people were traumatized by the accident and the rapid relocation that followed. Lacking reliable information, they were fearful and anxious about their current and future health and often perceived themselves as weak and helpless victims rather than as survivors.

Regarding agriculture, the contamination of crops, meat, and milk with short-lived radioactive iodine was a major concern in the early months after the accident. Now and for decades to come, contamination with longer-lived radioactive cesium is the main concern in some rural areas.

Forest food products such as berries, mushrooms, and game contain particularly high levels of long-lived radioactive cesium and this contamination is expected to remain high for several decades.

As a result of the accident, water bodies and fish became contaminated with radioactive materials. The contamination soon decreased as a result of dilution and decay but some of the materials remained trapped in the soils around contaminated rivers and lakes. Today, most water bodies and fish have low radioactivity levels, although the levels in some closed lakes remain high.

The accident immediately affected many plants and animals living within 30 km of the site. There was an increase in mortality and a decrease in reproduction and some genetic anomalies in plants and animals are still reported today [2, р. 11]. Over the years, as the radioactivity levels decreased, the biological populations started to recover and the area has become a unique sanctuary for biodiversity. But that's not to suggest that the area has returned to normal, or will at any point in the near future. Because of the long-lived radiation in the region surrounding the former Chernobyl Nuclear Power Plant, the area won't be safe for human habitation for at least 20,000 years.

1. 
   Chernobyl [Electronic resource]. – Mode of access: http://www.live science.com/39961-chernobyl.html. – Date of access: 17.03.2015.
   
2. 
   Chernobyl’s Legacy: Health, Environmental and Socio-Economic Impacts and Recommendations to the Governments of Belarus, the Russian Federation and Ukraine // The Chernobyl Forum: 2003–2005. – 55 p.
   

В статье анализируются проблемы, возникшие в результате взрыва на Чернобыльской атомной электростанции. Авторы описывают медицинские, экологические, экономические и психологические последствия аварии. Также рассматриваются изменения, которые произошли на зараженных территориях с течением времени, и перспективы этих территорий.