9 man-made disasters that had a big impact on our world

Volodymyr Repik/AP

Humans have had a huge impact on our environment.
Some of the deadliest disasters in world history were caused by human activity.
Chernobyl was considered the world’s worst nuclear power accident.
The Union Carbide Cyanide gas leak caused a death toll in the thousands.
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You may hear about natural disasters often, but some of the deadliest disasters in world history have been anthropogenic hazards (environmental disasters caused by human activity).

For this list, we’re focusing on incidents (and accidents) involving nature that were caused or worsened by people and their machines. From oil spills and explosions to nuclear testing fallout, these are some ecological disasters that changed our world forever.

Many believe that The Dust Bowl was caused by ignorance about farming practices.

Flickr/USDAgov

Before World War I, the land on the American Great Plains had mostly been used to raise cattle and other stock animals. Then, millions of acres were put under plow so that farmers could grow wheat.

After a decade of healthy rainfall and intense plowing of virgin soil by people with little to no knowledge of the land or the environmental conditions, a severe drought hit the American plains. Dry eroded topsoil turned to dust, and when high winds went sweeping through it, created devastating storms. The worst of it occurred on April 14, 1935, a day nicknamed Black Sunday because of a "black blizzard" — or dust storm — hundreds of miles wide and thousands of feet high that seemed to turn day into night and lasted for several hours.

Caused by a combination of nature and human error, the Dust Bowl is thought to have left an estimated 500,000 people homeless and caused an estimated 2.5 million to pack up and move elsewhere. Dust pneumonia, also called "brown plague," is also thought to have killed hundreds of people, many of whom were infants or elderly.

Chernobyl was considered the world’s worst nuclear power accident.

REUTERS/Gleb Garanich/Files

On April 26, 1986, an accident at the Chernobyl nuclear power plant near Kiev, Ukraine, caused high levels of radiation in the area. The information around the accident is still fairly hazy because, at the time, Ukraine was part of the Soviet Union and the government initially tried to keep the explosion under wraps.

Likely because of their downplay and the lack of knowledge, many plant workers and firefighters were exposed to radiation. Within three months, 30 people died of acute radiation sickness but thousands were affected, including the hundreds of thousands who were evacuated from nearby cities Kiev and Pripyat.

Early nuclear testing in the United States had environmental and health impacts for those who lived near the sites.

AP Photo/File

The United States government conducted 200 nuclear tests at sites in several states in the American south and west including Nevada, Arizona, Washington, and New Mexico from 1945 to 1962.

It was later discovered that fallout from the tests severely compromised the health of those who worked directly with the hazardous materials, others who worked on-site, and even those who just lived in areas "downwind," later referred to as "downwinders."

Exposure from radiation from the tests was linked to thyroid cancer and leukemia and it’s hard to know exactly how many people died as a result of the fallout from the tests.

Some early estimates had the death toll in the thousands, but one recent estimate by University of Arizona economist Keith Meyers put the number at 340,000 to 690,000. Eltona Henderson, with Idaho Downwinders, told the Salt Lake City Tribune that she saw entire families "wiped out by cancer" believed to be linked to these tests.

In 1990, Congress passed the Radiation Exposure Compensation Act to pay tens of thousands of sick Americans and their families between $50,000 and $100,000 each.

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