Measurements of personal exposure to NO2 and modelling using ambient concentrations and activity data

Abstract This study was undertaken with the aim of estimating true personal exposures from data that are less costly and more easily obtained than in detailed measurement programs. We present an evaluation of simple methodologies for estimating true personal exposure to nitrogen dioxide (NO 2 ) that take into account spatiotemporal variability in ambient concentrations across urban areas and which link the latter to personal exposure through indoor/outdoor (I/O) ratios determined from time-activity diaries. To allow us to both develop and evaluate the methods, we designed a measurement program involving volunteers across Melbourne wearing personal passive samplers. Three methods of estimating indoor–outdoor ratios and three approaches to calculating ambient exposure, including network monitors and the complex air quality model TAPM-CTM, were evaluated. All methods except one produced good agreement with the measured values. Importantly, the percentile statistics and standard deviations predicted by these spatial-variation techniques matched well the distribution seen in the measurements. For the best estimates of personal exposure to NO 2 , it is recommended that the I/O ratio be calculated using a mass balance method, requiring participants to record daily gas cooking periods and approximate house age. The recommended method for calculating the required ambient outdoor concentration is to use values from the network monitor nearest to a person’s microenvironment. Our research has identified a simple exposure methodology that could be widely applied for epidemiological cohort studies and population exposure estimates in urban areas with fixed monitoring networks, with only minimum information from respondents.

[1]  Erik Lebret,et al.  Small area variations in ambient NO2 concentrations in four European areas , 2000 .

[2]  Naresh Kumar,et al.  An Optimal Spatial Sampling Design for Intra-Urban Population Exposure Assessment. , 2009, Atmospheric environment.

[3]  S. Bartell,et al.  Interpersonal and daily variability of personal exposures to nitrogen dioxide and sulfur dioxide , 2004, Journal of Exposure Analysis and Environmental Epidemiology.

[4]  James A Mulholland,et al.  An examination of exposure measurement error from air pollutant spatial variability in time-series studies , 2010, Journal of Exposure Science and Environmental Epidemiology.

[5]  P. Koutrakis,et al.  Ozone exposure assessment in a southern California community. , 1997, Environmental health perspectives.

[6]  Ranjeet S. Sokhi,et al.  Performance characteristics of MM5-SMOKE-CMAQ for a summer photochemical episode in southeast England, United Kingdom , 2008 .

[7]  Peter J Hurley,et al.  An approach for estimating exposure to ambient concentrations , 2007, Journal of Exposure Science and Environmental Epidemiology.

[8]  John Carras,et al.  The Australian Air Quality Forecasting System. Part I: Project Description and Early Outcomes , 2004 .

[9]  R. Burnett,et al.  Spatial Analysis of Air Pollution and Mortality in Los Angeles , 2005, Epidemiology.

[10]  C. Dimitroulopoulou,et al.  Personal exposure of children to air pollution , 2009 .

[11]  Peter J. Hurley,et al.  TAPM: a practical approach to prognostic meteorological and air pollution modelling , 2005, Environ. Model. Softw..

[12]  J. Sarnat,et al.  Development of a personal multi-pollutant exposure sampler for particulate matter and criteria gases , 1999 .

[13]  M. Jerrett,et al.  Spatial sampling for intra-urban population exposure assessment: Response to a comment by Dr. Naresh Kumar☆ , 2009 .

[14]  Luc Int Panis,et al.  Disaggregation of nation-wide dynamic population exposure estimates in The Netherlands: Applications of activity-based transport models , 2009 .

[15]  P. Zawar-Reza,et al.  Intraurban-scale dispersion modelling of particulate matter concentrations : Applications for exposure estimates in cohort studies , 2006 .

[16]  Altaf Arain,et al.  A review and evaluation of intraurban air pollution exposure models , 2005, Journal of Exposure Analysis and Environmental Epidemiology.

[17]  Davy Janssens,et al.  The contribution of activity-based transport models to air quality modelling: a validation of the ALBATROSS-AURORA model chain. , 2009, The Science of the total environment.

[18]  D. Zmirou,et al.  Relationships between Nitrogen Dioxide Personal Exposure and Ambient Air Monitoring Measurements among Children in Three French Metropolitan Areas: VESTA Study , 2001, Archives of environmental health.

[19]  Bert Brunekreef,et al.  Modeling the intra-urban variability of outdoor traffic pollution in Oslo, Norway—A GA2LEN project , 2007 .

[20]  Ari Karppinen,et al.  A model for evaluating the population exposure to ambient air pollution in an urban area , 2002 .

[21]  S. Alm,et al.  Nitrogen Dioxide Exposure Assessment and Cough among Preschool Children , 2000, Archives of environmental health.

[22]  W. Mcdonnell,et al.  Long-term inhalable particles and other air pollutants related to mortality in nonsmokers. , 1999, American journal of respiratory and critical care medicine.

[23]  J. Brook,et al.  Associations between personal exposures and fixed-site ambient measurements of fine particulate matter, nitrogen dioxide, and carbon monoxide in Toronto, Canada , 2006, Journal of Exposure Science and Environmental Epidemiology.

[24]  Michelle L Bell,et al.  The use of ambient air quality modeling to estimate individual and population exposure for human health research: a case study of ozone in the Northern Georgia Region of the United States. , 2006, Environment international.

[25]  Pavlos S. Kanaroglou,et al.  Establishing an air pollution monitoring network for intra-urban population exposure assessment: A location-allocation approach , 2005 .