Is natural gas poisonous?

Natural gas in its pure form is primarily composed of methane, which is not toxic to humans at low concentrations. It is generally considered non-poisonous and is often used safely for heating, cooking, and generating electricity. However, while the gas itself is not poisonous, it can lead to dangerous situations if not handled properly, such as the risks associated with explosive mixtures in the air or suffocation in enclosed spaces due to oxygen displacement.

The other options suggest scenarios where natural gas could be poisonous or hazardous, but they misinterpret the nature of methane. The suggestion that it is only poisonous in large quantities lacks specificity, as natural gas can displace oxygen in confined spaces, leading to a potential asphyxiation hazard rather than a toxicological one. The statement regarding combustion refers to the byproducts produced when natural gas is burned, such as carbon monoxide, which can indeed be hazardous. However, that does not pertain to the toxicity of natural gas itself in its unburned state. Overall, the classification of natural gas as non-poisonous is accurate under standard conditions.