Which gas is a known contributor to indoor air pollution?

Each of the gases listed contributes to indoor air pollution in different ways.

Carbon dioxide is a common byproduct of human respiration and combustion processes. High levels of carbon dioxide can be a concern in poorly ventilated spaces, as it can lead to decreased air quality and may cause discomfort or health issues.

Ammonia, which can be released from various household products such as cleaners and fertilizers, can contribute to respiratory issues, particularly in individuals with preexisting conditions. It is also commonly found in tobacco smoke and agricultural settings, adding to its role as an indoor pollutant.

Carbon monoxide is particularly dangerous because it is a colorless, odorless gas that can result from faulty heating systems, gas appliances, and vehicle exhaust. It can lead to serious health effects, including poisoning, if levels become elevated in indoor environments.

Each of these gases poses health risks and contributes to the overall problem of indoor air quality, making it appropriate to conclude that all of them are known contributors to indoor air pollution.