2006 Progress Report: Air Toxics Exposures Among Teenagers in New York City and Los Angeles—A Columbia-Harvard Study (TEACH)

EPA Grant Number: R828678C001
Subproject: this is subproject number 001 , established and managed by the Center Director under grant R824834
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: Mickey Leland National Urban Air Toxics Research Center (NUATRC)
Center Director: Beskid, Craig
Title: Air Toxics Exposures Among Teenagers in New York City and Los Angeles—A Columbia-Harvard Study (TEACH)
Investigators: Kinney, Patrick L. , Pederson, Dee C. , Spengler, John D. , Ross, James M. , Johnson, Dave , Aggarwal, Maneesha , Ramstrom, Sonja , Chillrud, Steven
Current Investigators: Kinney, Patrick L. , Spengler, John D. , Ramstrom, Sonja , Chillrud, Steven
Institution: Columbia University - Mailman School of Public Health , Harvard T.H. Chan School of Public Health , Lamont Doherty Earth Observatory of Columbia University
Current Institution: Columbia University - Mailman School of Public Health , Harvard T.H. Chan School of Public Health
EPA Project Officer: Chung, Serena
Project Period: January 1, 1997 through January 31, 2005
Project Period Covered by this Report: January 1, 2005 through January 31, 2006
RFA: Mickey Leland National Urban Air Toxics Research Center (NUATRC) (1997) RFA Text |  Recipients Lists
Research Category: Air Quality and Air Toxics , Targeted Research

Objective:

The New York City TEACH Study

The Toxics Exposure Assessment: A Columbia Harvard Project (TEACH) study, funded by the National Urban Air Toxics Research Center (NUATRC), was designed to collect and analyze data on personal exposures to urban air toxics among inner city youths in New York City (NYC) and Los Angeles (LA) and to investigate factors that influence those exposures. This is a report on the NYC portion of the TEACH study.

Air monitoring was carried out two seasons per city. Simultaneous personal, home indoor, and home outdoor data were collected over six to nine weeks on high school students from non-smoking homes among a population of largely inner city Black and Hispanic teenagers. Simultaneous monitoring was carried out at upwind and urban ambient fixed sites. Every sampling event involved integrated 48-hour sampling for PM2.5, black carbon, up to 28 elements of particulate matter (PM), and a suite of 15 volatile organic compounds (VOCs) and two aldehydes. The multi-elements, mass soot, and VOC concentrations along with critical ancillary information, allow the partitioning of risk by season, gender, outdoor sources, indoor sources and mode of transportation, among other factors of interest.

For the NYC portion of the study, 46 students participated in the monitoring, 33 of whom participated in both seasons. These participants ranged in age from 14 to 19 were predominantly Black and/or Hispanic, lived in relatively small rental apartments in multi-floor apartment buildings, and lived in neighborhoods with relatively high levels of self-reported motor vehicle traffic.

The overall objective of the study was to characterize levels of and factors influencing personal exposures to urban air toxics among high school students living in inner city neighborhoods. The study had five principal aims:

Aim 1: To describe and compare weekday personal exposures to urban air toxics in two representative groups of 30 high school students (NYC and LA) and analyze seasonal changes in exposures and activity patterns.

Aim 2: To evaluate the contributions of indoor and outdoor air toxics concentrations to personal exposures in winter and summer. In addition, to evaluate the influence of time-activity patterns and home ventilation rates on those relationships.

Aim 3: To assess the contributions of a range of source categories of personal, outdoor, and/or indoor exposures using data on individual VOCs, aldehydes, and particulate components.

Aim 4: To characterize home indoor and outdoor exposures to the soluble fraction of selected metals and to correlate these measurements with simultaneous fixed-site outdoor measurements.

Aim 5: To develop and design a methodology for a nationwide study addressing personal exposures to urban air toxic pollutants.

The Los Angeles TEACH Study

This report is the Los Angeles portion of the TEACH study. The New York City portion of the study has been published. A draft final report for the LA portion was received on December 14, 2004. The report was reviewed by external peer-review. To complete the revisions and scientific editing for the report, the study was granted a no-cost extension through June 2005. The comments of the external reviewers and the SAP have been communicated to Dr Kinney. The NUATRC is waiting for a revised report from Dr Kinney.

The purpose of this research effort was to study the personal exposures to urban air toxics experienced by a group of students living in New York City (NYC) and in Los Angeles (LA). The study would provide information on the roles of seasons and days of the week, different meteorological conditions and daily activities on exposures to selected volatile organic compounds (VOC), aldehydes, and metals on particles (<2.5μ) present in the environment. Soluble fractions of selected metals were also assayed for correlations with source measurements. Exposure measurements were made in indoor, outdoor and personal environ­ments. The investigators related these exposures to the apportionment of air toxics among area, point, and mobile sources, as well as non-anthropogenic sources.

The specific aims were:

Aim 1: Describe the distributions of air toxics measured on personal, home indoor, home outdoor, and ambient fixed site locations in LA. Compare these data with concentrations measured in NYC.

Approach: Distributions of measured air concentrations are presented for each compound stratified by sample location and season. Results for NYC are presented and compared for selected air toxics.

Aim 2: Distinguish the roles of season and the impact of urban areas on ambient concentrations of air toxics in LA.

Approach: Concentrations of air pollutants were compared across seasons and “urban” contributions were determined by comparing concentrations between the urban fixed-site and a background site.

Aim 3: Analyze the relationship between home indoor and home outdoor air toxic concentrations in LA and assess source strengths for VOCs indoors.

Approach: Rank pollutants by indoor/outdoor ratios. Compare I/O ratios across seasons and across levels of individual home air exchange rates. Distinguish between pollutants for which indoor levels appear to be driven by indoor sources vs. those driven by outdoor concentrations. Calculate the source strengths for VOCs driven by indoor sources.

Progress Summary:

The New York City TEACH Study

Subject and Home Characteristics
Time-activity patterns were similar to previous surveys of urban young people, except that commuting by cars was uncommon in this population. Subway and bus commuting were common.

Personal Air Toxic Exposures
For pollutants with significant indoor sources, including most of the VOCs, personal exposures showed little relationship to outdoor concentrations. For those pollutants lacking significant indoor sources, including most PM associated elements and a few VOCs, both personal and indoor exposures were associated with outdoor levels. Strong temporal correlations were observed between central site ambient data and mean personal exposures for PM2.5, sulfate, and black carbon. In addition, a significant spatial correlation was found between home outdoor and personal black carbon levels, with a stronger correlation in winter. Neither PM2.5 nor sulfate exhibited spatial correlations between outdoor and personal levels. Personal exposures were significantly higher than home indoor and ambient samples for several elements, including iron, manganese and chromium. The iron/manganese and chromium chromium/manganese ratios, as well as strong correlations among these elements, suggested steel dust as the source of thee metals for a large subset of the personal samples. Furthermore, time-activity data suggested the NYC subway system to be a possible source of these elevated personal metals. The levels and ratios of iron, manganese, and chromium in a single set of duplicate PM2.5 samples integrated over eight hours of underground subway exposure are consistent with the subway system being the predominant source of these metals to subway-riding subjects.

Indoor Air Toxic Concentrations
Indoor VOC levels were generally much higher than outdoors, and thus indoor/outdoor (I/O) ratios were above 1.0 for most compounds. However, I/O ratios closer to 1.0 were observed for a few VOCs, including methyl tertiary butyl either (MTBE), benzene, ethylbenzene, toluene, and xylenes (BETX). Indoor/outdoor ratios were also lower in summer than in winter, reflecting, and an increased air exchange during summer as compared to winter. The I/O ratios for PM-associated elements were typically close to or below 1.0, reflecting the role played by outdoor sources in driving indoor levels. For a few elements, including cadmium potassium, and tin in winter and chromium and tin in summer, I/O rations greater than 1.0 were observed. For analytes with I/O ratios appreciably greater than 1.0 those ratios showed consistent declines at higher air exchange rates.

During the winter season, indoor and personal black carbon concentrations can be useful as an alternative to sulfate for tracing PM2.5 of ambient origin. In contrast sulfate, black carbon measurements are far more related to local urban particle emissions than to regional air masses. Hence, black carbon may be a useful ambient tracer in future studies addressing the health impacts of traffic-related particulate matter.

Outdoor Air Toxic Concentrations
Ambient concentrations of most VOCs were lower than levels measured indoors or as personal samples. Because of the relatively low concentrations measured in ambient air, median outdoor concentrations at the urban fixed site were below the respective limits of detection for six of 17 VOCs. Better detection results were obtained for the indoor and personal samples. With the exception of chromium, all median concentrations of ambient PM2.5 and associated elements exceeded limits of detection.

Analysis of spatial and temporal variations in ambient concentrations revealed two distinct groups of air toxics: those related to regional air masses (for example sulfur, selenium, arsenic, and formaldehyde) and those related to local sources for (example, black carbon, cobalt, lanthanum, nickel, MTBE, other BTEX, and VOCs). Concentration variations for compounds of the former group were greater over time than space, whereas the latter group showed greater variability across locations that across time. A large urban influence was seen for the BETX VOCs, as well as many particle components, especially those associated with combustion of heating oil and diesel fuel. The urban effect was generally larger in winter than in summer. A statistical variance components analysis using a mixed effects model confirmed many of these observations.

Patterns of elemental and VOC concentrations across sites and seasons strongly suggest that outdoor transportation and heating fuel combustion represent the two most significant sources of urban air toxics in NYC. A preliminary source apportionment analysis of ambient VOC and aldehyde data showed that primary emissions from motor vehicles were the dominant source category, followed by formation of secondary compounds and specific point sources.

The Los Angeles TEACH Study

The TEACH study monitored personal, home indoor and outdoor, and fixed-site outdoor air toxics concentrations in two groups of high school students, one in NYC and the other in LA. The study provided extensive descriptive data on exposures to a wide range of air pollutants experienced by youth living in the disadvantaged urban cores of America’s two largest cities. The sampling design (see below and Table 1 of section 2.1) enabled the examination of a wide range of factors that may influence personal exposures to urban air toxics, including home air exchange rate, indoor and outdoor sources, and individual activity patterns. In addition, the design captured information on several important sources of variability that may drive personal exposures: variability across days, subjects, seasons, and cities.

A large data set comprised of 17 VOCs, 2 aldehydes, particle mass PM2.5, soot fraction as well as 29 elements was assembled and quality assured for all the LA samples collected outdoors, indoors, and as personal samples. In addition, home and personal characteristics, air exchange rates, and other variables comprise the analysis data set available for assessing air toxic exposures and subsequent risk.

Key Findings:

The Los Angeles TEACH Study

Subject and Home Characteristics
Air toxics exposure data were for 40 inner city LA youth ranging in age from 13 to 17. Subjects were predominantly Hispanic, lived predominantly in attached or detached single family homes, and in neighborhoods with medium to low self-reported motor vehicle traffic. Time-activity patterns were similar to previous surveys of urban youth.

Personal Exposures to Air Toxics
Personal exposures showed the impacts of both indoor and outdoor concentrations, as well as sources that are encountered in unmeasured microenvironments. For pollutants with significant indoor sources, including many of the VOCs, personal exposures showed minimal to moderate relationships to outdoor concentrations. For other pollutants lacking significant indoor sources, including most PM-associated elements and a few VOCs, personal (and indoor) exposures showed strong associations with outdoor levels.

Indoor Air Toxic Concentrations
Indoor VOC levels were generally much higher than outdoors, and thus indoor/outdoor ratios were above 1.0 for most compounds. However, I/O ratios closer to 1.0 were observed for a few VOCs, including MTBE and some of the other BETX VOCs (benzene, ethylbenzene, toluene and xylenes). I/O ratios tended to be lower in fall than in winter, reflecting increased air exchange during fall compared to winter. Using the indoor and outdoor concentration data, along with air exchange measurements, we estimated indoor source strengths for selected VOCs. Median I/O ratios for PM associated elements were typically close to or below 1.0, reflecting the role played by outdoor sources in driving indoor levels. For analytes with I/O ratios greater than 1.0, I/O ratios decreased with increasing air exchange. For analytes with I/O ratios less than 1, the ratios consistently increased with increasing AER. These results were similar to the NYC results.

Outdoor Air Toxic Concentrations
As expected, ambient concentrations of most VOCs were lower than levels measured indoors or on personal samples. Because of the relatively low concentrations measured in ambient air, median outdoor concentrations at the urban fixed site were below the respective limits of detection for several VOCs. Better detection results were obtained for the indoor and personal samples. All median ambient PM2.5 and associated elemental concentrations exceeded limits of detection. A preliminary source apportionment analysis suggested that motor vehicles represented the dominant source of ambient VOC concentrations in both Los Angeles and New York.

Conclusions:

The New York City TEACH Study

The study provided extensive descriptive data on exposures to a wide range of air pollutants encountered by youths living in the urban cores of America’s two largest cities. In addition, the design captured information on several important sources of variability that may drive personal exposures: variability across days, variability across subjects, variability across seasons, and, finally, variability across cities. The design facilitates analyses of the relationships among simultaneously collected personal, home indoor and outdoor measurements, and urban fixed site data and the exploration of factors that may influence these relationships, such as air exchange rate, indoor and outdoor sources, and activity patterns.

Future Activities:

The Los Angeles TEACH Study

  • NUATRC is expecting the revised LA report from Dr Kinney.
  • Following receipt of the report, it will be edited by technical editors and published as a NUATRC report.


Journal Articles on this Report : 4 Displayed | Download in RIS Format

Other subproject views: All 15 publications 5 publications in selected types All 5 journal articles
Other center views: All 144 publications 62 publications in selected types All 53 journal articles
Type Citation Sub Project Document Sources
Journal Article Chillrud SN, Epstein D, Ross JM, Sax SN, Pederson D, Spengler JD, Kinney PL. Elevated airborne exposures of teenagers to manganese, chromium, and iron from steel dust in New York City's subway system. Environmental Science & Technology 2004;38(3):732-737. R828678C001 (2004)
R828678C001 (2006)
R828678C001 (2007)
R828678C001 (Final)
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  • Abstract from PubMed
  • Associated PubMed link
  • Abstract: ES&T-Abstract
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  • Journal Article Chillrud SN, Grass D, Ross JM, Coulibaly D, Slavkovich V, Epstein D, Sax SN, Pederson D, Johnson D, Spengler JD, Kinney PL, Simpson HJ, Brandt-Rauf P. Steel dust in the New York City subway system as a source of manganese, chromium, and iron exposures for transit workers. Journal of Urban Health 2005;82(1):33-42. R828678C001 (2005)
    R828678C001 (2006)
    R828678C001 (2007)
    R828678C001 (Final)
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  • Abstract: Springer-Abstract
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  • Journal Article Kinney PL, Chillrud SN, Ramstrom S, Ross J, Spengler JD. Exposures to multiple air toxics in New York City. Environmental Health Perspectives 2002;110(Suppl 4):539-546. R828678C001 (2002)
    R828678C001 (2003)
    R828678C001 (2004)
    R828678C001 (2006)
    R828678C001 (2007)
    R828678C001 (Final)
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  • Abstract from PubMed
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  • Journal Article Sax SN, Bennett DH, Chillrud SN, Kinney PL, Spengler JD. Differences in source emission rates of volatile organic compounds in inner-city residences of New York City and Los Angeles. Journal of Exposure Analysis and Environmental Epidemiology 2004;14(Suppl 1):S95-S109. R828678C001 (2004)
    R828678C001 (2006)
    R828678C001 (2007)
    R828678C001 (Final)
    R827027 (2002)
    R832141 (2006)
    R832141 (2007)
    R832141 (Final)
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  • Abstract: Nature-Abstract & Full Text HTML
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  • Supplemental Keywords:

    RFA, Health, Scientific Discipline, PHYSICAL ASPECTS, Air, INTERNATIONAL COOPERATION, POLLUTANTS/TOXICS, HUMAN HEALTH, particulate matter, air toxics, Environmental Chemistry, Health Risk Assessment, Exposure, Chemicals, Risk Assessments, Susceptibility/Sensitive Population/Genetic Susceptibility, Physical Processes, Children's Health, genetic susceptability, Atmospheric Sciences, Environmental Policy, Biology, copollutant exposures, health effects, sensitive populations, urban air, atmospheric particulate matter, aldehydes, fine particles, PM 2.5, long term exposure, inhaled pollutants, acute lung injury, acute cardiovascular effects, airway disease, VOCs, air pollution, children, susceptible subpopulations, cardiac arrest, New York, cardiopulmonary response, chronic health effects, human exposure, Los Angeles, lung inflammation, particulate exposure, assessment of exposure, Acute health effects, indoor air, inhaled, human susceptibility, children's environmental health, Volatile Organic Compounds (VOCs), acute exposure, air quality, human health risk, toxics, environmental hazard exposures, air contaminant exposure, co-pollutants

    Relevant Websites:

    http://www.sph.uth.tmc.edu/mleland/ Exit

    Progress and Final Reports:

    Original Abstract
  • 1997
  • 1998
  • 1999
  • 2000
  • 2001 Progress Report
  • 2002 Progress Report
  • 2003 Progress Report
  • 2004 Progress Report
  • Final Report

  • Main Center Abstract and Reports:

    R824834    Mickey Leland National Urban Air Toxics Research Center (NUATRC)

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R824834C001 Air Toxics Exposures Among Teenagers in New York City and Los Angeles - A Columbia-Harvard Study (TEACH)
    R824834C002 Cardiopulmonary Response to Particulate Exposure
    R824834C003 VOC Exposure in an Industry Impacted Community
    R824834C004 A Study of Personal Exposure to Air Toxics Among a Subset of the Residential U.S. Population (VOC Project)
    R824834C005 Methods Development Project for a Study of Personal Exposures to Toxic Air Pollutants
    R824834C006 Relationship Between Indoor, Outdoor and Personal Air (RIOPA)
    R824834C007 Development of the "Leland Legacy" Air Sampling Pump
    R824834C008 Source Apportionment of Indoor Polycyclic Aromatic Hydrocarbons (PAHs) in Urban Residences
    R824834C009 Development of a Personal Cascade Impactor Sampler (PCIS)
    R824834C010 Testing the Metals Hypothesis in Spokane
    R828678C001 Air Toxics Exposures Among Teenagers in New York City and Los Angeles—A Columbia-Harvard Study (TEACH)
    R828678C002 Cardiopulmonary Effects of Metal-Containing Particulate Exposure
    R828678C003 VOC Exposure in an Industry Impacted Community
    R828678C004 A Study of Personal Exposure to Air Toxics Among a Subset of the Residential U.S. Population (VOC Project)
    R828678C005 Oxygenated Urban Air Toxics and Asthma Variability in Middle School Children: A Panel Study (ATAC–Air Toxics and Asthma in Children)
    R828678C006 Relationship between Indoor, Outdoor and Personal Air (RIOPA). Part II: Analyses of Concentrations of Particulate Matter Species
    R828678C007 Development of the “Leland Legacy” Air Sampling Pump
    R828678C008 Source Apportionment of Indoor PAHs in Urban Residences 98-03B
    R828678C009 Development of a Personal Cascade Impactor Sampler (PCIS)
    R828678C010 Testing the Metals Hypothesis in Spokane
    R828678C011 A Pilot Geospatial Analysis of Exposure to Air Pollutants (with Special Attention to Air Toxics) and Hospital Admissions in Harris County, Texas
    R828678C012 Impact of Exposure to Urban Air Toxics on Asthma Utilization for the Pediatric Medicaid Population in Dearborn, Michigan
    R828678C013 Field Validation of the Sioutas Sampler and Leland Legacy Pump – Joint Project with EPA’s Environmental Technology Validation Program (ETV)
    R828678C014 Performance Evaluation of the 3M Charcoal Vapor Monitor for Monitor Low Ambient Concentrations of VOCs
    R828678C015 RIOPA Database Development
    R828678C016 Contributions of Outdoor PM Sources to Indoor and Personal Exposures: Analysis of PM Species Concentrations” Focused on the PM Speciation and Apportioning of Sources
    R828678C017 The Short and Long-Term Respiratory Effects of Exposure to PAHs from Traffic in a Cohort of Asthmatic Children