Air Toxics: The HEI Research Program

1
Air ToxicsThe HEI Research Program

• Debra A. Kaden
• Health Effects Institute
• 2004 Air Quality Symposium Air Toxics
• Endicott House
• Dedham, MA
• August 4-5, 2004

2
Outline

• HEI Air Toxics research program
• Completed studies
• Current studies
• Looking ahead
• Future research
• Air Toxics Review effort

3
HEI Air Toxics ResearchThe Three Bs

• Benzene, Butadiene, and Biomarkers
• Research planning efforts pointed towards
  benzene, 1,3-butadiene, POM, and aldehydes
• Issues identified included extrapolation across
  exposures and extrapolation across species

4
HEI Air Toxics ResearchBenzene and 1,3-Butadiene

• Benzene
• Metabolites as biomarkers (Melikian)
• Low dose metabolism (Turteltaub)
• Chromosomal markers and mechanism (Eastmond)
• Biomarker validation in human population (Qu)

From Qu et al 2003. HEI Research Report Number
115
5
HEI Air Toxics ResearchBenzene and 1,3-Butadiene

• 1,3-Butadiene
• Development of biomarkers for exposure to
  1,3-butadiene
• - DNA adducts (Blair)
• - mutation spectra (Recio, Walker)
• - hemoglobin adducts (Swenberg)
• Biomarker validation in human population
  (Albertini)
• Mechanism (Henderson)

From Albertini et al 2003. HEI Research Report
Number 116
6
HEI Air Toxics ResearchAldehydes

• Assessing exposure to aldehydes
• Real-world automotive exposure tunnel study
  (Grosjean)
• Personal exposure monitors (Zhang)
• Relationship among indoor, outdoor, and personal
  exposures (RIOPA)
• The RIOPA study also included evaluation of
  exposure to particulate matter and volatile
  organic compounds, and was co-funded with the
  Mickey Leland National Urban Air Toxics Research
  Center

7
HEI Air Toxics ResearchPOM

• Ad hoc
• Toxicity of atmospheric transformation products
  (Arey)
• Chemical and toxicity characterization of
  atmospheric transformation products from diesel
  emissions (Zielinska) - ongoing

8
Current HEI ResearchReal-world exposures

• How to evaluate health risks? C x T
• Animal studies at high exposures
• Extrapolation across species and concentrations
• Epidemiology studies in occupationally exposed
  groups
• Usually exposure to single chemical, in healthy
  worker population
• One-at-a-time versus mixtures
• Other air toxics, other pollutants, other
  variables (weather, topography)

9
Current HEI Research RFA 03-1 the Hotspots RFA

• Asks how high exposures are in upper end
  ambient settings
• How hot is hot?

10
Current HEI Research RFA 03-1 the Hotspots RFA

• The Hotspots
• In and around idling trucks near industrial park
  (Smith)
• Near the Buffalo/Ontario port of entry across
  U.S./Canadian border (Spengler)
• Around the Southern California air basin (Fujita)
• In a residential neighborhood that has both heavy
  mobile sources and a high concentration of
  industrial facilities (Lioy)
• Around homes close to roadways (Harrison)

11
Current HEI ResearchTargeted air toxics
Diesel exhaust organic gases are a complex
mixture, containing many of the other air toxics
included on this list.
12
The Hotspot studiesFujita

• Exposure to Air Toxics in Mobile Source Dominated
  Microenvironments
• Measurements made during the summer and winter
• Microenvironments representative of in-cabin
  exposures of commuters and residents living
  adjacent to busy roadways
• Use various monitors with temporal and spatial
  resolution
• Determine gradients in concentrations from
  roadways to fixed sites
• Characterize and estimate contributions of
  gasoline- and diesel-powered vehicles to exposures

13
The Hotspot studiesSpengler

• Air Toxics Exposure from Vehicular Emissions at a
  US Border Crossing
• Peace Bridge Exposure Study
• Will characterize impact of vehicular emissions
  at the Buffalo, New York Border Crossing on
  adjacent communities
• Particles and gasses measured at fixed locations
  upwind and adjacent to the Peace Bridge Plaza
• Additional fixed sites in the neighborhoods of
  West Buffalo
• Mobile sampling systems with GPS locators

14
The Hotspot studiesSmith

• Air Toxics Hotspots in Industrial Parks and
  Traffic
• Add vapor and aldehyde collectors to particle
  sampling system in ongoing PM study in industrial
  parks, downwind neighborhoods, and in-vehicle
  locations
• Characterize exposure intensity and variation of
  VOC components by location characteristics
• Examine relationships between VOC exposures and
  the levels and composition of particles

15
The Hotspot studiesLioy

• Personal and Ambient Exposures to Air Toxics in
  Camden, New Jersey
• Measure ambient, personal exposures for people
  living in hotspot (Waterfront South area) and
  control (Copewood/Davis Sts.) neighborhoods of
  Camden, New Jersey
• Examine relationship between measured personal
  exposures and neighborhood concentrations
• Assess impact of industrial and mobile sources on
  measured neighborhood concentrations and
  personal exposures

16

The Hotspot studiesHarrison

• Measurement and modelling of exposure to air
  toxics and verification by biomarker
• Direct measurements of personal exposures of
  non-smoking volunteer subjects from a wide range
  of residential locations
• Measurement of microenvironment concentrations of
  air toxics
• Optimization and verification of a model of
  personal exposures estimated from
  microenvironment measurements and time-activity
  diaries
• Comparison of measured personal exposures to
  benzene with urinary excretion of the biomarker
  S-phenylmercapturic acid
• Produce a scheme for categorizing exposure (by
  compound) according to location of residence and
  other lifestyle and exposure factors for use in
  epidemiological studies

17
Looking ahead Getting to Health Effects

• Follow up to Hotspots RFA studies
• Hotspot investigators had begun to identify
  potential affected populations
• If suspected hotspot areas are high, issue RFA to
  follow up with health effects studies in exposed
  populations

18
Mobile Source Air Toxics Research and
ReviewDriving influences

• Its time!!
• Upcoming EPA Mobile Source Air Toxics rulemaking
• Southern California Mobile Air Toxics Exposure
  study (MATES III)
• Air toxics challenges in highway lawsuits

19
Looking ahead

• Mobile Source Air Toxics Review
• Assemble panel of experts
• HEI Research Committee, HEI Review Committee,
  other experts
• Review exposure and toxicity literature (from
  peer-reviewed literature)

20
Looking ahead

• Mobile Source Air Toxics Review (cont.)
• Identify highest priority mobile source air
  toxics
• Identify research gaps
• Timeline
• Launch early this fall
• Disseminate findings during and at end (18 months)

21
HEI Air Toxics Research

• Thank you!
• dkaden_at_healtheffects.org