title: Toxicological evaluation of realistic emission source aerosols (TERESA)--power plant studies: assessment of breathing pattern.
abstract: Our approach to study multi-pollutant aerosols isolates a single emissions source, evaluates the toxicity of primary and secondary particles derived from this source, and simulates chemical reactions that occur in the atmosphere after emission. Three U.S. coal-fired power plants utilizing different coals and with different emission controls were evaluated. Secondary organic aerosol (SOA) derived from α-pinene and/or ammonia was added in some experiments. Male Sprague-Dawley rats were exposed for 6 h to filtered air or different atmospheric mixtures. Scenarios studied at each plant included the following: primary particles (P); secondary (oxidized) particles (PO); oxidized particles + SOA (POS); and oxidized and neutralized particles + SOA (PONS); additional control scenarios were also studied. Continuous respiratory data were obtained during exposures using whole body plethysmography chambers. Of the 12 respiratory outcomes assessed, each had statistically significant changes at some plant and with some of the 4 scenarios. The most robust outcomes were found with exposure to the PO scenario (increased respiratory frequency with decreases in inspiratory and expiratory time); and the PONS scenario (decreased peak expiratory flow and expiratory flow at 50%). PONS findings were most strongly associated with ammonium, neutralized sulfate, and elemental carbon (EC) in univariate analyses, but only with EC in multivariate analyses. Control scenario O (oxidized without primary particles) had similar changes to PO. Adjusted R(2) analyses showed that scenario was a better predictor of respiratory responses than individual components, suggesting that the complex atmospheric mixture was responsible for respiratory effects.
authors.affiliation: Department of Environmental Health, Harvard School of Public Health, Boston, MA 02115, USA. eadiaz@hsph.harvard.edu
authors.forename: Edgar A
authors.initials: EA
authors.lastname: Diaz
authors.forename: Miriam
authors.initials: M
authors.lastname: Lemos
authors.forename: Brent
authors.initials: B
authors.lastname: Coull
authors.forename: Mark S
authors.initials: MS
authors.lastname: Long
authors.forename: Annette C
authors.initials: AC
authors.lastname: Rohr
authors.forename: Pablo
authors.initials: P
authors.lastname: Ruiz
authors.forename: Tarun
authors.initials: T
authors.lastname: Gupta
authors.forename: Choong-Min
authors.initials: CM
authors.lastname: Kang
authors.forename: John J
authors.initials: JJ
authors.lastname: Godleski
mesh_terms: D000393:Air Pollutants / Q000633:toxicity*; D000818:Animals; D003031:Coal; D004781:Environmental Exposure / Q000009:adverse effects*; D004784:Environmental Monitoring / Q000379:methods; D019570:Inhalation Exposure / Q000009:adverse effects*; D008297:Male; D008962:Models, Theoretical; D052638:Particulate Matter / Q000633:toxicity*; D010993:Plethysmography, Whole Body; D011210:Power Plants; D051381:Rats; D017207:Rats, Sprague-Dawley; D012119:Respiration / Q000187:drug effects*; D012129:Respiratory Function Tests; D018675:Toxicity Tests
chemical_list: D000393:Air Pollutants; D003031:Coal; D052638:Particulate Matter