How Nature Is Recovering After The Chernobyl Disaster
On April 26th 1986, reactor no. 4 in the Chernobyl Nuclear Power Plant exploded and released radioactive materials into the atmosphere. Major quantities of plutonium, strontium-90, caesium-137 and iodine-131 escaped. Over 200000 square km was contaminated, with 70% of the area comprising the countries of Ukraine, Russia and Belarus.
In areas where it was raining at that time and for the next 10 days, deposits of contaminants were higher. Plutonium will remain in the environment for hundreds of thousands of years; but, at a lower level, followed by strontium-90 and caesium-137 that will be present for decades to come.
Large amounts of radioactive materials were deposited in urban areas around the plant. Other urban areas were also contaminated but at varying levels. Up to date the residents of these areas are still exposed to some external radiation. Building roofs, roads, parks and lawns were contaminated, but there has been a reduction because of the effects of cleanup, street washing, traffic, rain and wind. Apart from some undisturbed soils in parks and gardens, levels of radiation are back to normal in Ukraine, Russia and Belarus.
Agricultural areas also suffered a great deal. The land and crops were contaminated. Dairy cows grazing on contaminated pasture produced iodine contaminated milk in Ukraine, Russia and Belarus. Due to factors such as weather and decay, levels of radioactive materials in plants and animals decreased quickly in the following years. For example, the caesium-137 levels are now lower than international levels. However, where dairy cows are grazing in the former Soviet Union and the soil is uncultivated, the levels of radiation are still of concern. High levels of caesium-137 may still be contained in the milks produced in Ukraine, Russia and Belarus.
The animals and vegetation in affected forests and mountains are still highly contaminated. Food products derived from the environment including game, berries and mushrooms contain high levels of caesium-137. Arctic and sub-Arctic areas have become victims because reindeer feed on lichens that easily take up radioactive caesium-137, which is then passed on to humans through reindeer meat.
Caesium-137 and strontium-90 are being carried off to aquatic bodies through rain. Lakes without outlets will be contaminated for longer periods.
In areas that were within 30 km, the immediate effect of radiation was death and mutation. But over time, animals and plants have recovered due to new migrations into the affected areas and decomposition of radioactive materials. Animals like horses sent in to live within the exclusion zone on an experimental basis have adapted to the environment without difficulty.