Chemical Mass Balance Source Apportionment of Indoor PM15 in Brazilian Corporate Offices and Restaurants

Abstract

We have applied the chemical mass balance air quality receptor model (CMB) to particulate matter samples collected indoors during regular working hours at six locations in and around the cities of São Paulo and Campinas, São Paulo state, Brazil. Source profiles were used to apportion indoor PM 15 to urban dust, residual oil, soft wood, natural gas, diesel emissions, charbroiled meat, brake dust, sodium chloride, and potassium nitrate. At all sites, diesels con tributed a significant fraction, ranging from 10 to 45 % of the PM₁₅ mass. In a steak house and a pizzeria, soft wood burning contributed 23 and 26% of the mass, respectively. Except for an office located in a rural area, charbroiled meat emissions comprised a significant fraction of the PM₁₅ mass, ranging from 7% in a pizzeria to 29% in a hotel which houses a steak house and other restaurants. Natural gas contribution at the hotel was 31 % of the mass, the highest of all sites. The lowest urban dust contribution (6%) was found at the steak house and the highest (16%) in a rural area.