Biomarkers for Air Pollutants: Development of Hemoglobin Adduct Methodology for Assessment of Exposure to Butadienes and Polycyclic Aromatic Hydrocarbons, SEER project of SIP: Experimental Program To Stimulate Competitive Research (EPSCoR) From The Commonwealth Of KentuckyEPA Grant Number: R829419E02
Title: Biomarkers for Air Pollutants: Development of Hemoglobin Adduct Methodology for Assessment of Exposure to Butadienes and Polycyclic Aromatic Hydrocarbons, SEER project of SIP: Experimental Program To Stimulate Competitive Research (EPSCoR) From The Commonwealth Of Kentucky
Investigators: Hurst, Harrell E. , Myers, Steven R.
Institution: University of Louisville
EPA Project Officer: Hunt, Sherri
Project Period: October 1, 2002 through September 30, 2004 (Extended to September 30, 2005)
Project Amount: $219,287
RFA: EPSCoR (Experimental Program to Stimulate Competitive Research) (2000) RFA Text | Recipients Lists
Research Category: EPSCoR (The Experimental Program to Stimulate Competitive Research)
These include development of methodology that will measure systemic exposures to chloroprene (2-Cl-1,3-butadiene CAS-126-99-8) and selected polycyclic aromatic hydrocarbons (PAH: fluoranthene, CAS# 205-44-0; benzo(a)pyrene, CAS# 50-32-8). Covalent adducts to the abundant blood protein hemoglobin formed by electrophilic pollutant metabolites will be investigated as quantitative biomarkers of exposure.
This project will extend methods for detection of exposure to carcinogenic electrophiles by measurement of covalent adducts formed in Hb by epoxide metabolites. This involves analysis of derivatives following Edman cleavage of globin N-terminal valine adducts. Quantification will be accomplished by selected ion monitoring gas chromatography/mass spectrometry (SIM-GC/MS) using stable isotope internal standards. Adducts from PAH exposure will be analyzed after acid hydrolysis of labile PAH-Hb carboxylate adducts, and analyzed at specific sites. Nucleophilic residues in Hb, such as cysteine sulfhydryl and histidine imidazole groups, will be examined following proteolytic cleavage of Hb with trypsin. Analysis of cleaved peptides containing adducts will be accomplished by electrospray ionization (ESI) LC/MS and matrix assisted laser desorption ionization time of flight (MALDI-TOF) MS. Tandem MS studies using triple quadrupole or ion trap instruments will monitor selected ion decomposition pathways to provide additional analytical specificity and sensitivity. High-resolution accurate mass GC/MS may be used as necessary to define adduct identities.
These studies will provide capability to assess potential, alleged, or systemic exposures through use of Hb adduct assay methodology for chloroprene and selected PAHs. We will determine sensitivity and reproducibility of adduct assay methods, and assess biomarker suitability for application to industrial and ambient air toxicant monitoring in limited animal studies. Such preliminary studies will provide a methodological basis for future public health studies to assess toxicant exposure in air.