How can scientists determine whether indoor air pollutants pose a health risk?
To determine whether pollutants may cause health effects, it is necessary to consider four aspects: • Toxicity of pollutants and their concentrations in indoor air. Indoor air can for instance contain organic compounds, particles, or microbes that may cause allergies or other health effects. • Exposure. People are mainly exposed to air pollutants when breathing but may also be exposed via other routes, such as dust ingestion. Since exposures can vary, even very low and very high exposures should be considered and not only average ones. • Exposure-response relationships. To assess the risk posed by a given pollutant, it is important to know how the body responds to different concentrations in air. Health effects observed in people who have been exposed to pollutants at work are valuable in determining the risks posed by a particular pollutant. However, such findings may not be directly applicable to the general public. • Risk characterisation. In the final step of the risk assessment pr
