Poison gases can cause injury more easily than solid or liquid poisons because they diffuse (move) in the air, exposing skin, and are easily breathed in. Immediate contact with corrosive gas leads to chemical burns of the skin and lungs. When absorbed into the inside of the human body and into the blood, either by breathing in or through skin, several poison gases cause a poisoning. In a poisoning, medical help is often necessary; simply removing the victim from the gas is not enough to prevent symptoms.