title: Personal exposure to ultrafine particles: Two-level statistical modeling of background exposure and time-activity patterns during three seasons.
abstract: Personal exposure to air pollution is associated with time- and location-specific factors including indoor and outdoor air pollution, meteorology and time activities. Our investigation aims at the description and identification of factors determining personal exposure to particle number concentration (PNC) in everyday situations. Ten volunteers recorded their personal exposure to PNC and kept an activity diary in three different seasons besides stationary measurements of ambient air pollution and meteorology. Background exposure to PNC was modelled using the most predictive variables. In a second step, the effects of the activities were calculated adjusted for the background exposure. The average personal PNC level was highest in winter and was three times higher than the mean stationary PNC level while staying indoors and two times higher while staying outdoors. Personal indoor PNC levels were significantly increased during the use of candles, cooking and the occurrence of smell of food. High stationary outdoor PNC levels and low dew point temperatures were associated with increased personal outdoor PNC levels. Times spent in public transport were associated with lower personal PNC levels than other times spent in transportation. Personal PNC levels in everyday situations exhibited a large variability because of seasonal, microenvironment-specific and activity-specific influences.
authors.affiliation: Statistical Consulting Unit, Department of Statistics, Ludwig-Maximilians-Universität, Munich, Germany.
authors.forename: Veronika
authors.initials: V
authors.lastname: Deffner
authors.affiliation: Statistical Consulting Unit, Department of Statistics, Ludwig-Maximilians-Universität, Munich, Germany.
authors.forename: Helmut
authors.initials: H
authors.lastname: Küchenhoff
authors.affiliation: Statistical Consulting Unit, Department of Statistics, Ludwig-Maximilians-Universität, Munich, Germany.
authors.forename: Verena
authors.initials: V
authors.lastname: Maier
authors.affiliation: Bavarian Environment Agency (LfU), Augsburg, Germany.
authors.forename: Mike
authors.initials: M
authors.lastname: Pitz
authors.affiliation: Helmholtz Zentrum München, Institute of Epidemiology II, Neuherberg, Germany.|Environment Science Center, Universität Augsburg, Augsburg, Germany.
authors.forename: Josef
authors.initials: J
authors.lastname: Cyrys
authors.affiliation: Helmholtz Zentrum München, Institute of Epidemiology II, Neuherberg, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Breitner
authors.affiliation: Helmholtz Zentrum München, Institute of Epidemiology II, Neuherberg, Germany.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Schneider
authors.affiliation: Helmholtz Zentrum München, Institute of Epidemiology II, Neuherberg, Germany.|Environment Science Center, Universität Augsburg, Augsburg, Germany.
authors.forename: Jianwei
authors.initials: J
authors.lastname: Gu
authors.affiliation: Helmholtz Zentrum München, Institute of Epidemiology II, Neuherberg, Germany.
authors.forename: Uta
authors.initials: U
authors.lastname: Geruschkat
authors.affiliation: Helmholtz Zentrum München, Institute of Epidemiology II, Neuherberg, Germany.
authors.forename: Annette
authors.initials: A
authors.lastname: Peters
mesh_terms: D000203:Activities of Daily Living; D000393:Air Pollutants / Q000032:analysis*; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D004784:Environmental Monitoring; D005858:Germany; D006801:Humans; D008685:Meteorological Concepts; D015233:Models, Statistical; D008962:Models, Theoretical; D010316:Particle Size; D052638:Particulate Matter / Q000032:analysis*; D012621:Seasons; D012828:Silicones / Q000032:analysis*; D013997:Time Factors
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter; D012828:Silicones