Activity Patterns Applied to Pollutant Exposure Assessment: Data from a Personal Monitoring Study in Los Angeles

There have been many recent advances in exposure assessment methods. Studies of the spatial and temporal distribution of pollutants (Ott and Eliassen 1973; Wright et al. 1975; Cortese and Spengler 1976) and the contribution of indoor sources (NAS 1980; Spengler and Sexton 1983; Yocum 1982) have led us away from models that predict exposure solely on the basis of concentrations recorded by regional fixed-site monitors to those that incorporate concentrations recorded in various indoor and outdoor environments. Most recently, emphasis has focused on the concept of total human exposure. If exposure is defined as the intersection between a person and a pollutant concentration (Ott 1982), total exposure can be conceptualized as a function of the time spent in contact with various pollutant concentrations. A basic supposition underlying this concept of total human exposure is that people's activity patterns (the locations they visit, when they visit them, and what they do there) influence their exposure to pollutants.