Idly levels of radiation in order to secure the facility from further radiation leaks.

The prevailing winds at the time of the accident were from the south and east, so much of the radiation plume traveled northwest toward Belarus. Nonetheless, Soviet authorities were slow to release information about the severity of the disaster to the outside world. But when radiation alarms began to go off at a nuclear plant in Sweden, authorities were forced to reveal the full extent of the crisis.

Within three months of the Chernobyl accident, a total of 31 people died from radiation exposure or other direct effects of the disaster, according to the NRC, UNSCEAR and other sources. More than 6,000 cases of thyroid cancer may eventually be linked to radiation exposure in Ukraine, Belarus and Russia, though the precise number of cases that are directly caused by the Chernobyl accident is difficult (if not impossible) to ascertain.

Surprisingly, the overall rate of cancer deaths and other health effects related to Chernobyl's radiation leak is lower than was initially feared. "The majority of the five million residents living in contaminated areas … received very small radiation doses comparable to natural background levels (0.1 rem per year)," according to an NRC report. "Today the available evidence does not strongly connect the accident to radiation-induced increases of leukemia or solid cancer, other than thyroid cancer."

Some experts have claimed that unsubstantiated fear of radiation poisoning led to greater suffering than the actual disaster. For example, many doctors throughout Eastern Europe and the Soviet Union advised pregnant women to undergo abortions to avoid bearing children with birth defects or other disorders, though the actual level of radiation exposure these women experienced were too low to cause any problems. Even the United Nations published a report on the effects of the Chernobyl accident that was so "full of unsubstantiated statements that have no support in scientific assessments," according to the chairman of UNSCEAR, that it was eventually dismissed by most authorities.
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[Pin It] Dead forest at the Chernobyl site.
Credit: dreamstime
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Environmental impacts

Shortly after the radiation leaks from Chernobyl occurred, the trees in the woodlands surrounding the plant were killed by high levels of radiation. This region came to be known as the "Red Forest" because the dead trees turned a bright ginger color. The trees were eventually bulldozed and buried in trenches.

The damaged reactor was hastily sealed in a concrete sarcophagus intended to contain the remaining radiation: How effective this sarcophagus has been — and will continue to be into the future — is a subject of intense scientific debate. Plans to construct a safer and more permanent containment structure around the reactor have yet to be implemented.

Despite the contamination of the site — and the inherent risks in operating a reactor with serious design flaws — the Chernobyl nuclear plant continued operation for many years, until its last reactor was shut down in December of 2000. The plant, the ghost towns of Pripyat and Chernobyl, and a large area surrounding the plant known as the "zone of alienation" are largely off-limits to humans.

There are, however, exceptions: A few hundred former residents of the area have returned to their former homes, despite the risks of radiation exposure. Scientists, government officials and other personnel are allowed on the site for inspections and other purposes. And in 2011, Ukraine opened up the area to tourists who want to see firsthand the after-effects of the disaster.
Chernobyl today

The region today is widely known as one of the world's most unique wildlife sanctuaries. Thriving populations of wolves, deer, lynx, beaver, eagles, boar, elk, bears and other animals have been documented in the dense woodlands that now surround the silent plant. Only a handful of radiation effects, such as stunted trees growing in the zone of highest radiation and animals with high levels of cesium-137 in their bodies, are known to occur. [Infographic: Chernobyl Nuclear Disaster 25 Years Later]

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.