Methane is a colourless and oderless gas often used for heating and light. It is formed naturally by the decay of natural materials and is common in landfills, sewers, septic systems and marshes. Methane is also a component of intestinal gas in people. In low concentrations, the health effects of methane gas are minimal, but it can create dangerous health issues in high concentrations and can be dangerous because it is highly flammable.
Methane is Highly Flammable
The "rotten egg" smell associated with methane, the principal component of natural gas, does not actually occur naturally. Commercial gas companies add hydrogen sulphide to natural gas so the smell will be noticed in the event of a leak. The primary reason for this is if there is a leak and any type of spark or fire is introduced, the methane will ignite and can cause an explosion large enough to be life-threatening.
Methane Can Cause Asphyxiation
In high concentrations, methane can deprive the body of oxygen and cause asphyxiation. According to the Canadian Center for Occupational Health, oxygen must be at a minimum of 18 per cent or asphyxiation will occur. Exposure to lower levels of methane may cause dizziness, headache, or a general feeling of fatigue. These symptoms will subside once exposure to methane has ended.
Along with oxygen, nitrogen, hydrogen, and carbon dioxide, methane is produced by the body during digestion, creating intestinal gas. This can cause intense but usually brief pain until the gas is expelled from the body. Methane produced as a result of intestinal gas is not generally considered a serious, long-term health issue.
Long-term Health Effects of Methane Exposoure
There is no evidence of any health issues caused by long-term exposure to methane gas. The Wisconsin Department of Health noted no evidence that cancer, damage to reproductive organs, or damage to internal organs occurs as a result of exposure to methane.