Oklahoma plans to start using nitrogen gas for executions, officials said Wednesday, in what will be the first such method of capital punishment in the United States.

The state is turning to nitrogen after it and other states became unable to acquire drugs required for lethal injections because of opposition from manufacturers to their products being used for capital punishment.

Nitrogen is an odorless and tasteless gas that makes up about 78 percent of the air humans breathe but causes death when inhaled without any oxygen.