Grantee Research Project Results
2005 Progress Report: Validation of Diesel Exhaust Biomarkers
EPA Grant Number: R832097Title: Validation of Diesel Exhaust Biomarkers
Investigators: Zhang, Junfeng , Lioy, Paul J. , Stern, Alan , Kipen, Howard , Zhang, Lin , Fiedler, Nancy , Ohman-Strickland, Pamela , Laumbach, Robert
Institution: University of Medicine and Dentistry of New Jersey , New Jersey Department of Environmental Protection
Current Institution: Environmental and Occupational Health Sciences Institute , New Jersey Department of Environmental Protection , University of Medicine and Dentistry of New Jersey
EPA Project Officer: Aja, Hayley
Project Period: May 1, 2005 through April 30, 2008
Project Period Covered by this Report: May 1, 2005 through April 30, 2006
Project Amount: $572,497
RFA: Application of Biomarkers to Environmental Health and Risk Assessment (2004) RFA Text | Recipients Lists
Research Category: Air Toxics , Air Quality and Air Toxics , Air
Objective:
The objective of this research project is to examine whether urinary amino-polycyclic aromatic hydrocarbons (PAHs) can serve as biomarkers of diesel exhaust exposure, as amino-PAHs are metabolites of nitro-PAHs, a group of chemical compounds that are emitted specifically by diesel engines. The target amino-PAHs are 1-aminopyrene, 1-aminonaphthalene, 2-aminonaphthalene, and 3-aminobenzanthrone. The study is being carried out in 50 healthy nonsmoking men and women during two 1-hour controlled exposure sessions to a diluted diesel exhaust (DE), and to clean air. The specific objectives of this research project are to: (1) optimize an amino-PAH analysis method to increase the sensitivities and recoveries and reduce the cost of sample analysis; (2) determine how long after DE exposure urinary amino-PAH concentrations reach maximum levels; (3) quantify inhalation exposure to the parent nitro-PAHs of each of the target biomarkers during the entire time window of urinary monitoring and minimize potential interferences from exposures that may occur before and after the controlled exposure session; (4) estimate the fraction of inhaled nitro-PAHs converted into amino-PAH metabolites and excreted in the urine; and (5) assess interindividual biomarker variability with respect to several physiological factors, such as gender, age, and body mass index.
Progress Summary:
During Year 1 of the project, we have optimized all the laboratory analysis conditions and finalized standard operating procedures. The final methods have sensitivities, precisions, and recoveries similar to or better than the published methods. The methods include a high-performance liquid chromatography(HPLC)/fluorescence technique for analyzing amino-PAHs in human urine samples and a gas chromatography/electron capture detection technique for analyzing nitro-PAHs in the air. We have characterized an atmosphere containing diluted DE (at a nominal PM10 concentration of 300 μg/m3) for nitro-PAHs, a group of compounds that are considered to be uniquely emitted from diesel-powered engines. In this atmosphere, mean concentrations of nitronaphthalenes, 1-nitropyrene, and 3-nitrobenzanthrone were 0.73, 1.40, and 0.73 ng/m3, respectively.
At the end of Year 1 of the project, 20 subjects have completed the experiments. The majority of target compounds in the urine samples were above method detection limits: 100 percent for 1-hydroxypyrene, approximately 90 percent for 1-aminonaphthalene, approximately 87 percent for 2-aminonaphthalene, approximately 75 percent for 1-aminopyrene, and approximately 78 percent for 3-aminobenzanthrone. Proper statistical analyses have not been conducted at this stage of the project. A quick review of the data, however, shows that 1-hour exposure to the diluted DE led to an increase in urinary concentration of 1-aminopyrene and 3-aminobenzanthrone. The exposure also led to an increase in urinary 1-hydroxypyrene concentration. A metabolite of pyrene, 1-hydroxypyrene, which is released from combustion of diesel and other fuels as well as tobacco, however, is less diesel specific than amino-PAHs.
Future Activities:
We will continue to conduct experiments and perform data analyses to examine whether urinary amino-PAHs can serve as biomarkers of exposure to DE.
Journal Articles:
No journal articles submitted with this report: View all 4 publications for this projectSupplemental Keywords:
urinary metabolites, exposure, biomonitoring, air toxics, amino-PAHs, nitro-PAHs, 1-hydroxypyrene,, Health, RFA, Air, Scientific Discipline, Health Risk Assessment, Risk Assessments, particulate matter, Environmental Chemistry, Environmental Monitoring, diesel exhaust, inner city, chemical characteristics, aerosol composition, airborne particulate matter, human exposure, ambient air monitoring, environmental risks, atmospheric particles, atmospheric aerosol particles, particulates, atmospheric particulate matter, biomarker, ambient air quality, air pollution, human health risk, PAHProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.