Advancing Exposure Science and Its Applications

The mission of most environmental organizations around the world is to safeguard human health and the environment. In the United States, air quality management practice relies on the ambient concentrations of pollutants of concern and the success of a regulatory strategy is assessed by determining whether pollutant emissions have been reduced and ambient concentration levels have decreased. Some countries (e.g. United Kingdom) assess the success of their regulatory strategy by determining whether exposure reduction have occured. Exposure is defined as the contact of a stressor with a receptor for a given duration of time. It is now well-recognized that ambient concentrations and human exposure levels are not the same. Hence, it is important to better understand exposure levels since exposure is the link between environmental pollution and human and ecosystem health. Exposure science deals with comprehensive understanding of the relationship among pollutant emissions, pollutant transport and fate, pollutant levels that people breathe in and stressor levels to sensitive ecosystems, and associates health effects. Given the increasing complexity of current and emerging environmental problems, exposure science must play a pivotal role in developing and implementing most meaningfull and cost-effective emission control policies. Theis paper provides exposure framework to identify and minimize exposures to harmful pollutants, thereby better protectinf human ecosystem health.