Biomonitoring of Human Exposure to Biomass Burning -- A Proposed Collaboration with GA Tech Zheng (Jane) Li, Courtney D Sandau PAH and Combustion Exposure Biomarker Section Organic Analytical Toxicology Branch Division of Laboratory Sciences National Center for Environmental Health Centers for Disease Control and Prevention Atlanta, GA 30341

What is Biomarker? Biomarkers of exposure refer to cellular, biochemical, analytical, or molecular measures that are obtained from biological media such as tissues, cells, or fluids and are indicative of exposure to an agent.

What is Biomonitoring? A Assessment of internal dose exposure by measuring a toxicant, or its metabolite or reaction product (biomarker) in human blood, urine, saliva, adipose, or other tissue

Exposure and health effects pathway External dose: air, water, food, soil Internal dose: blood, serum, urine, tissue Biologically effective dose: blood, tissue Health effect inhalation ingestion skin absorption Exposure assessment Health effects assessment Location: nearness to source

Predicting levels of toxicants in people using environmental monitoring is very difficult and includes many assumptions Mathematical Modeling Air levels Water levels Soil/dust levels Food levels Lifestyle factors Personal habits Nutritional status Genetic factors Lung, intestine and skin absorption coefficients MANY OTHER FACTORS Predicted levels of toxicants in people Instead of predicting, we measure levels of chemicals in people

Biomonitoring provides unique information for -- The public health response to a known or suspected excessive exposure to a toxicant(s) or a pollutant(s). Health research to determine what toxicants and what internal dose levels cause disease or death Human data significantly decrease uncertainty in assessing human risk

National Report on Human Exposure to Environmental Chemicals (NHANES) st NHANES report released 27 chemicals 2003 – 2 nd NHANES report 116 Chemicals 14 OH-PAHs: 1-OH-pyrene 3-OH-fluoranthene 2/3-OH-fluorene 1/2/3-OH-phenanthrene 3/6-OH chrysene 1/3-OH-benz[a]anthracene 1/2/3-OH-benzo[c] phenanthrene

PAH & Combustion Exposure Biomarker Laboratory CDC currently monitors Group A (2-4 aromatic ring) PAH-OH metabolites, conducted in our laboratory CDC currently monitors Group A (2-4 aromatic ring) PAH-OH metabolites, conducted in our laboratory Newly developed method has LOD for most of 23 OH- PAHs at low ppt Newly developed method has LOD for most of 23 OH- PAHs at low ppt Expanding to include metabolites of Group B (5 and more aromatic ring, e.g. OH-benzo[a]pyrene), and amino-PAHs, metabolites of NO 2 -PAH. Expanding to include metabolites of Group B (5 and more aromatic ring, e.g. OH-benzo[a]pyrene), and amino-PAHs, metabolites of NO 2 -PAH. Initializing and developing methods to monitor human exposure to biomass burning Initializing and developing methods to monitor human exposure to biomass burning

Exposure Study on Biomass Burning – a Challenge Large emissions Large emissions Numerous classes and uncountable chemicals released in biomass fires Numerous classes and uncountable chemicals released in biomass fires Various emission profiles from different burning sources Various emission profiles from different burning sources Particles and aerosols with organic compounds condensed on the surface can be transported over long distance Particles and aerosols with organic compounds condensed on the surface can be transported over long distance

Emissions From Biomass Burning CO, NO X, SO 2, O 3 Particulate Matter Resin acids PAHs and alkyl PAHs Anhydrosugars, e.g. levoglucosan Methoxyphenols PCDD and PCDF Many others… Alkyl amides and nitriles

One major group of compounds studied as biomarkers One major group of compounds studied as biomarkers Softwood guaiacyl compds Softwood guaiacyl compds Hardwood syringyl compds Hardwood syringyl compds A urinary assay of methoxyphenols for biomonitoring wood smoke exposure has been developed A urinary assay of methoxyphenols for biomonitoring wood smoke exposure has been developed Potential Markers for Biomass Burning -- Methoxyphenols

A major group of organic pollutants formed during incomplete combustion A major group of organic pollutants formed during incomplete combustion Mutagenic and carcinogenic Mutagenic and carcinogenic Most abundant ones are pyrene, phenanthrene, fluoranthene, benzo(a/e)pyrene, chrysene, etc. Most abundant ones are pyrene, phenanthrene, fluoranthene, benzo(a/e)pyrene, chrysene, etc. Alkyl-PAHs, e.g. pimanthrene and retene, suggested to be the major source specific biomarkers in pine smoke Alkyl-PAHs, e.g. pimanthrene and retene, suggested to be the major source specific biomarkers in pine smoke Potential Markers for Biomass Burning -- PAHs

Relative amounts of alkyl-PAHs to the parent PAHs – petrogenic source vs. combustion source Relative amounts of alkyl-PAHs to the parent PAHs – petrogenic source vs. combustion source Relative amounts of unstable or kinetic PAHs to the more stable or thermodynamic PAHs – combustion or anthropogenic input Relative amounts of unstable or kinetic PAHs to the more stable or thermodynamic PAHs – combustion or anthropogenic input Acenaphthene and acenaphthylene – combustion source; cadalene and retene – plant source Acenaphthene and acenaphthylene – combustion source; cadalene and retene – plant source PAHs, Source-specific Markers

Analytical Techniques Extraction Extraction Solid phase extraction (SPE) or silica/florisil column for further sample clean up Solid phase extraction (SPE) or silica/florisil column for further sample clean up Gas chromatography/mass spectrometry Gas chromatography/mass spectrometry –GC/Time-of-flight (TOF) MS –GC x GC/TOFMS –GC/high-resolution MS Isotope dilution for precise and accurate measurements Isotope dilution for precise and accurate measurements

Identification of Unknown Markers -- GC/TOFMS 19 OH-PAH mix 6 minutes 1-nap 2-nap 9-fluo 3-fluo 2-fluo 1-,2-,3-,4-,9-phen 1-bcp 2-bcp 1-baa 6-chry 3-bcp 3-chry 3-baa 3-flran 1-pyr LECO Pegasus III Fast GC/TOFMS Separation Full Scan Extensive library search Unknown peak identification De-convolution

Identification of Unknowns -- GC x GC/TOFMS 4-Dimensional GC x GC-TOFMS 4-Dimensional GC x GC-TOFMS Two distinctive separation mechanisms, such as polar and non-polar Two distinctive separation mechanisms, such as polar and non-polar Improving resolution, reducing chromatographic co-elution – more accurate analyte identifications Improving resolution, reducing chromatographic co-elution – more accurate analyte identifications Ideal for obtaining maximum information from complex samples Ideal for obtaining maximum information from complex samples

GC x GC/TOFMS Contour plot Mixture of 58 compds: 37 PCBs 11 PPs 1 BB 8 BDEs Courtesy slide from Jef Focant

GC x GC/TOFMS Contour plotShade surface plot Courtesy slide from Jef Focant

Quantitation – GC/HRMS Finnigan MAT95 GC/HRMS High resolution (10,000) High sensitivity ( times more sensitive than other common GC/MS) 37 PAH mixture

Objectives Identify source-specific markers for biomass combustions Identify source-specific markers for biomass combustions –Verify and confirm reported markers –Search for new ones Identify optimal metabolites in human body for biomonitoring Identify optimal metabolites in human body for biomonitoring –Parent compounds or metabolites –Urine or blood Perform studies on populations exposed to biomass burning Perform studies on populations exposed to biomass burning

Possible Population/Field Studies Exposure assessment to indoor air pollution caused by domestic biomass burning in developing countries, e.g. China, India, etc. Exposure assessment to indoor air pollution caused by domestic biomass burning in developing countries, e.g. China, India, etc. Occupational and residential exposure to forest fires Occupational and residential exposure to forest fires Exposure study on large scale agricultural burning, e.g. sugarcane burning in Brazil and Costa Rica Exposure study on large scale agricultural burning, e.g. sugarcane burning in Brazil and Costa Rica