The world’s most poisonous lake once killed 1700 people.

5-7

8-10

11-13

14-15

So you’ve probably heard of poisonous snakes and spiders — but an entire lake? Yes, it’s true. Lake Nyos in the African country of Cameroon which sits inside the crater of a volcano was once a regular, large blue lake. But one mysterious day in 1986, that was about to change…

It was evening when nearby famers heard a strange rumbling sound and saw a giant jet of water shoot out of the lake and form into a giant, white cloud above it. But when the farmers walked over to investigate, they fell to the floor. The cloud contained poisonous gas and hovered over the lake for two days. When it finally disappeared, some of the people who had collapsed actually woke up but 1,700 people and many animals for miles around had died. Meanwhile, the lake had turned a muddy, orange color.

What caused the toxic cloud?

It turned out that the cloud was made up of carbon dioxide gas which is dangerous in big amounts. Scientists weren’t sure how this came to be in the lake but later agreed that it must have leaked into the water over a period of time and sunk to the bottom. Then a landslide disturbed the calm waters and set about a chain of events that caused the lake to shoot out water and all the gas at once which made the poisonous cloud. Strangely enough, the same thing happened at a smaller lake in Cameroon just a couple of years earlier. Authorities have since put pipes into both lakes which lets the water bubble up to the surface so that carbon dioxide is released into the air in small amounts but the entire area is still too unsafe for people to live in.

What is carbon dioxide used for?

Carbon dioxide is kind of like oxygen to plants! They use it to make their food during the photosynthesis process. But the gas, sometimes known as CO2 is also used in small amounts within man-made products, such as the bubbles in fizzy soda!

By Deborah L. Caine (Whyzz writer)