A Backpack's Worth of Data: Elevated Teen Cancer Risks Linked to Air Pollution

Article excerpt

It is difficult to assess the cancer risks associated with exposures to air pollutants because much of the health focus has been on the major outdoor pollutants; far less is known about exposures inside homes and buildings, where pollutants may be far more concentrated. Better assessments would measure personal exposures to inhaled pollutants, but such measurements are both costly and challenging to collect. Now a research team has developed an effective method to monitor personal exposures to air pollution with the goal of estimating cancer risks for indoor and outdoor exposures in urban areas [EHP 114:1558-1566; Sax et al.].

The team recruited 87 high school students from Los Angeles and New York City. Three types of measurements were obtained: indoor home samples, outdoor home samples, and personal exposure samples. To obtain personal exposure samples, each teenager wore a regular backpack modified to carry sampling equipment and various types of samplers for aldehydes, particles, and volatile organic compounds (VOCs). This enabled sampling of air wherever the teenager spent time over a 48-hour period, providing an integrated measurement of the air exposures from all indoor and outdoor environments. The personal, ambient, and modeled concentrations were used together with EPA data and other toxicological information to determine excess cancer risks associated with the exposure levels.

In both cities, median cancer risks from personal VOC exposures were much greater than from ambient exposures. Of the VOCs measured, formaldehyde carried the greatest cancer risk (more than 1 in 1 million, based on current EPA data), despite the decline of indoor levels since the banning of formaldehyde foam insulation. …