Aryl Hydrocarbon Receptor-Mediated Activity of Particulate Organic Matter from the Paso del Norte Airshed along the U.S.-Mexico Border

• Published in: Environmental health perspectives Vol. 111; no. 10; pp. 1299 - 1305
• Main Authors: Arrieta, Daniel E., Ontiveros, Cynthia C., Li, Wen-Whai, Garcia, Jose H., Denison, Michael S., McDonald, Jacob D., Burchiel, Scott W., Washburn, Barbara Shayne
• Format: Journal Article
• Language: English
• Published: United States National Institute of Environmental Health Sciences. National Institutes of Health. Department of Health, Education and Welfare 01-08-2003; National Institute of Environmental Health Sciences
• Subjects: Air pollutants; Air Pollutants - adverse effects; Air Pollutants - analysis; Air pollution; Animals; Biomarkers; Cell culture techniques; Chemical hazards; Environmental agencies; Environmental Exposure - adverse effects; Environmental Exposure - analysis; Environmental health; Environmental Monitoring; Humans; Hydrocarbons, Chlorinated - adverse effects; Hydrocarbons, Chlorinated - analysis; Mexico; Mice; Mixing height; Mutagenesis; Mutagenicity; Particulate matter; Polychlorinated Biphenyls - adverse effects; Polychlorinated Biphenyls - analysis; Polycyclic aromatic hydrocarbons; Receptors, Aryl Hydrocarbon - drug effects; Risk; Tumor Cells, Cultured; United States; Vehicle Emissions - adverse effects; Vehicle Emissions - analysis; United States; Mexico; USA, Texas; USA, New Mexico; Mexico, Chihuahua
• ISSN: 0091-6765; 1552-9924
• DOI: 10.1289/ehp.6058

In this study, we determined the biologic activity of dichloromethane-extracted particulate matter < 10 μm in aerodynamic diameter ( PM10) obtained from filters at three sites in the Paso del Norte airshed, which includes El Paso, Texas, USA; Juarez, Chihuahua, Mexico, and Sunland Park, New Mexico, USA. The extracts were rich in polycyclic aromatic hydrocarbons (PAHs) and had significant biologic activity, measured using two in vitro assay systems: ethoxyresorufin-O-deethylase (EROD) induction and the aryl hydrocarbon-receptor luciferase reporter system. In most cases, both EROD (5.25 pmol/min/mg protein) and luciferase activities (994 relative light units/mg) were highest in extracts from the Advance site located in an industrial neighborhood in Juarez. These values represented 58% and 55%, respectively, of induction associated with 1 μM β-naphthoflavone exposures. In contrast, little activity was observed at the Northeast Clinic site in El Paso, the reference site. In most cases, luciferase and EROD activity from extracts collected from the Tillman Health Center site, situated in downtown El Paso, fell between those observed at the other two sites. Overall, a statistically significant correlation existed between PM10and EROD and luciferase activities. Chemical analysis of extracts collected from the Advance site demonstrated that concentrations of most PAHs were higher than those reported in most other metropolitan areas in the United States. Calculations made with these data suggest a cancer risk of 5-12 cases per 100,000 people. This risk estimate, as well as comparisons with the work of other investigators, raises concern regarding the potential for adverse health effects to the residents of this airshed. Further work is needed to understand the sources, exposure, and effects of PM10and particulate organic material in the Paso del Norte airshed.