Exposure assessment

When assessing effects or risks from environmental pollution, it is not enough to know contamination levels. We also need to take into account how an individual– or other animal or physical “receptor” – comes into contact with the pollutant. This is what is known as exposure assessment.

For example, people spend some 90 % of their time indoors. While outdoor pollutants are often a main source of indoor pollution, factors related to buildings and occupants may also govern resulting exposures.

Measures taken to reduce pollutant emissions are mostly driven by health concerns. Human behaviour and biological, sociological or technological factors need to be taken into account to ensure the maximum possible protection of human health. Our aim is to support authorities in their efforts to provide maximum health protection for all population groups, and to employ the most effective measures to reduce environmental health risks.

Exposure assessment at NILU is based on in-house atmospheric dispersion models, operated mainly in urban areas, extensive expertise in pollutant analysis and lately, our ability to analyse important human biomarkers of exposure such as oxidative stress. Our main interest is outdoor and indoor air pollution.

Exposure scenarios

Our latest approach is the development of exposure scenarios, a concept well known from risk assessment procedures. Atmospheric dispersion models allow us to estimate exposure for receptor points (e.g., homes or schools) with high spatial and temporal resolution. The exposure estimations are followed by questionnaires or statistical data that provide insight into time activity patterns. To further zero in on individual human exposure, we can employ personal sampling devices and time activity data.

Since the 1980s, NILU has developed models for exposure to outdoor air for a number of epidemiological and health risk assessment studies. The models target human exposures from industrial sources, traffic or domestic energy production in Norway, Europe and elsewhere. The institute has also developed human exposure models for exposure to particulate matter or PAHs from the air, and models that allow exposure patterns for selected population groups to be accounted for on a European level. We often extend our capabilities through collaboration with other researchers in Norway and abroad.