A new study suggests that most people inhale substantially more organic contaminants, including cancer-causing benzene, than is indicated by standard environmental risk assessments based on outdoor measurements.
"Ambient measurements at central sites aren't good predictors of [personal] exposure," says John Adgate of the University of Minnesota in Minneapolis. "Actual exposures are higher."
To monitor urban air quality, environmental agencies typically measure pollutant concentrations in samples collected at centralized outdoor locations and extrapolate individuals' average exposures from those measurements. That's a reasonable approach for studying ozone and other pollutants that form out-