Application of an Ir tracer to determine soot exposure to students commuting to school on Baltimore public buses.
An important component of urban aerosol, diesel soot is a known respiratory irritant and contains mutagenic and carcinogenic organic compounds.
To estimate student exposures to soot emitted from public diesel buses during commutes to city high schools, a portion of the Baltimore municipal fuel supply was tagged with an iridium tracer and exposure was monitored during commutes with personal aerosol monitors as a part of an Environmental Justice Project.
A total of 68.2 g of Ir as iridium (III) - 2,4-pentanedionate were used to induce a concentration of 48.5 mug Ir/l of fuel.
Twenty samples were collected over 10 days while four students commuted on regularly scheduled buses and a fifth student commuted by private car.
Individual samples integrated from 1 to 4 round trips.
Iridium analyses were performed instrumentally after neutron activation with a detection limit (DL) of about 500 fg.
For students commuting by bus and following protocols, Ir tracer concentrations ranged from 53±38 to>1980±49 fg/m3.
Concentrations up to 3530±220 fg/m3 were observed for student 5, who sampled only when boarding and disembarking.
Exposure were greatest for students commuting through the heavily trafficked central business district.
Corresponding estimates of exposures to soot emitted from municipal buses ranged from <=3 to 82 ng soot/m3 (<=145 ng/m3 for student 5) (...)
Mots-clés Pascal : Maryland, Etats Unis, Amérique du Nord, Amérique, Zone urbaine, Trafic routier, Véhicule à moteur, Autobus, Carburant diesel, Pollution air, Particule en suspension, Aérosol, Suie, Qualité air, Inventaire source pollution, Technique traceur, Iridium, Echantillonnage, Analyse activation neutronique, Exposition, Homme, Epidémiologie
Mots-clés Pascal anglais : Maryland, United States, North America, America, Urban area, Road traffic, Motor vehicle, Bus, Diesel fuel, Air pollution, Suspended particle, Aerosols, Soot, Air quality, Pollution source inventory, Tracer technique, Iridium, Sampling, Neutron activation analysis, Exposure, Human, Epidemiology
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 98-0366922
Code Inist : 001D16C04C. Création : 25/01/1999.