Environmental contamination and human exposure to airborne total and respirable manganese in Montreal.
Methylcyclopentadienyl manganese tricarbonyl (MMT) is an organometallic compound used as an octane improver in unleaded gasoline.
The combustion of MMT leads to the formation of manganese (Mn) oxides, mainly Mn3O4.
The objective of this study is to assess the variations over time and space of respirable (MnR) and total (MnT) Mn in the urban atmosphere and to evaluate human exposure by inhalation.
Two sampling sites were selected on the island of Montreal based on their local traffic density (municipal botanical garden, C-10000-15000 vehicles/d ; Montreal Waterworks, C+100000-130000 vehicles/d).
Air samplings were made during the day at stations located 10 m from the road using portable pumps, some of which were equipped with a cyclone.
MnR and MnT and other metals were measured on Teflon filters by neutron activation.
Mn exposure doses by inhalation were calculated using Monte-Carlo simulations.
MnR and MnT average concentrations were significantly higher at site C+ (MnR=0.024 mug/m3 ; MnT=0.050 mug/m3) than at site C- (MnR=0.015 mug/m3 ; MnT=0.027 mug/m3).
Temporal profiles at sites C+and site C-were similar, with a coefficient of correlation of 0.24 for MnR and 0.26 for MnT.
Trend analyses (ARIMA) also showed that the period of the week (work days vs. off days) was significantly related to MnR and MnT variations at both sites.
The average exposure dose by inhalation to MnR and MnT ranged from 0.001 to 0.030 mug/kg. day and 0.001 to 0.05 mug/kg. day. (...)
Mots-clés Pascal : Canada, Amérique du Nord, Amérique, Zone urbaine, Pollution air, Source pollution, Trafic routier, Essence, Antidétonant, Manganèse Carbonyle Complexe, Métal lourd, Manganèse, Qualité air, Teneur air, Variation spatiale, Variation temporelle, Toxicité, Exposition risque environnement, Inhalation, Simulation numérique, Méthode Monte Carlo
Mots-clés Pascal anglais : Canada, North America, America, Urban area, Air pollution, Pollution source, Road traffic, Gasoline, Antiknock additive, Manganese Carbonyl Complexes, Heavy metal, Manganese, Air quality, Air content, Spatial variation, Time variation, Toxicity, Environmental exposure, Inhalation, Numerical simulation, Monte Carlo method
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 97-0536684
Code Inist : 001D16C02. Création : 24/03/1998.