The 130th Annual Meeting of APHA

5022.0: Wednesday, November 13, 2002 - Board 6

Abstract #49808

Uncertainties surrounding the risk assessment of diesel particulate matter

Susan M. Chemerynski, MPH, Jonathan Borak & Company, 234 Church St., New Haven, CT 06510, 2037776611, susan@jborak.com, Jonathan B Borak, MD, DABT, School of Medicine, Yale University, 234 Church ST, Suite 1100, New Haven, CT 06510, Greg Sirianni, MS, Industrial Hygiene, Jonathan Borak & Company INC., 234 Church Street, Suite 1100, New Haven, CT 06510, and Howard J Cohen, PhD, CIH, University of New Haven, West Haven, CT, 300 Orange Avenue, West Haven, CT 06516.

Exposure to diesel particulate matter (DPM) has been a primary focus of public health concern, as potential cancer risk has been posed. Various risk assessments have been performed in order to quantify risk, however no definitive estimate of risk has been validated. Quantifying DPM exposure is difficult because it is a complex mixture of carbonaceous particulate coated by complex organic compounds. Analytical methods can quantify total DPM or its components, however the mix of components can vary for technical or ambient reasons and different analytical methods may yield differing results. There is also uncertainty about which DPM component is carcinogenic in humans. To better understand relationships among DPM components, we analyzed the results of >1000 personal air samples obtained from DPM-exposed underground and surface miners. Samples were analyzed by NIOSH Method 5040 which measures carbonaceous carbon (“elemental carbon”, EC), organic carbon (OC), and total carbon (TC). Mean EC varied from 59-402 ug/m3 underground and 2-6 ug/m3 above ground, while mean OC varied from 27-122 ug/m3 underground and 28-92 ug/m3 above ground. The EC:TC ratio varied from 2% to 75%, and there was no consistent relationship among EC, OC and TC. These findings indicate that EC, OC and TC are not interchangeable for cancer risk assessment and, because the mechanism of DPM-induced human cancer is unknown, it is not obvious which DPM component should be measured. Until these issues are addressed, risk assessments on DPM will remain inconclusive and the public health risks of DPM will remain uncertain.

Learning Objectives: At the conclusion of the session, the participant (learner) in this session will be able to

Keywords: Risk Assessment, Environmental Exposures

Presenting author's disclosure statement:
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.

Emerging Issues in Environmental Toxics and Infrastructure Development

The 130th Annual Meeting of APHA