The 1986 Chernobyl nuclear plant catastrophe in Ukraine was the most significant uncontrolled radioactive release recorded in history. The accident occurred on the 26^th of April 1986 when hydrogen and steam explosions at the Chernobyl plant’s Unit 4 resulted in a rupture in the reactor vessel and a fire that carried on for ten days.

The fire and explosions in the plant released large amounts of radioactive iodine and cesium into the atmosphere, especially around the plant. The wind carried the radioactive release over Belarus, the Russian Federation, Ukraine, and some parts of Europe. This caused severe economic and social disruption for Belarus, Russia, and Ukraine populations.

Source

Reports and health assessments on the incident in Chernobyl were published in the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR)- Health Effects Due To Radiation From The Chernobyl Accident 2008 and Evaluation Of Data On Thyroid Cancer In Regions Affected By The Chernobyl Accident 2018. The data in these assessments are based on 30 years of research on the health effects of radiation exposure.

The public and the workers from the plant were exposed to three kinds of radionuclides: Iodine-131, cesium-134, and cesium-137. Of the three radionuclides, cesium-137 and iodine-131 contributed significantly to the radiation dose delivered to the public.

There were 600 workers onsite the day of the accident. Around 134 suffered from radiation sickness, while 28 died in the first three months. Recovery took a long time for workers that survived the radiation sickness.

115,000 people that were evacuated from the area near the plant received a radiation dose of 30 mSv. As of 2015, around 20,000 cases were reported of thyroid cancer among the residents of Ukraine, Russia, and Belarus. 5,000 thyroid cancer cases were associated with children drinking milk contaminated with iodine from cows who had ingested contaminated grass following the accident. The other 15,000 thyroid cancer cases were due to other factors like increased incidence rate with the aging of the population, awareness about thyroid cancer, and efficient methods to detect the sickness.

According to several studies and assessments, people exposed to the radiation also had high anxiety levels, poor health, and unexplained physical/mental symptoms. There were no reported birth defects or decreased fertility cases in women and men.

The accident at Chernobyl became a massive health hazard for the regions around the plant. Fortunately, there were no global effects of the Chernobyl accident in North America and Asia.