Distributions of Indoor and Outdoor Air Pollutants in Rio de Janeiro, Brazil:  Implications to Indoor Air Quality in Bayside Offices

Abstract

An indoor air quality survey was conducted on selected floors in an office building in Rio de Janeiro, Brazil. The sampling sites comprised four offices located along the same vertical column of the building. Measurements were made on alternate days at the same time of day during working hours. Indoor and outdoor samples were collected for volatile organic compounds (VOC), formaldehyde, total suspended particles (TSP), nicotine, and ultraviolet respirable suspended particles (UV-RSP). Compared with formaldehyde, acetaldehyde was found in higher concentrations outdoors because of the use of ethanol or ethanol/gasoline blends as alternative fuels for automobiles in Brazil. The TVOC concentration ranged from 304.3 to 1679.9 μg/m 3 indoors and 22 to 643.2 μg/m 3 outdoors. The indoor level of total volatile organic compounds (TVOC) was especially high in the 13th floor office. A minor contribution from environmental tobacco smoke was found. TSP values exceed the Brazilian Legislation (80 μg/m 3 ) in both outdoor and indoor air in the office located near the street traffic. For all pollutants evaluated I/O ratios appeared to be higher in offices located on the top of the building. The characterization of indoor air pollutants allowed the suggestion of several remediation measures to improve air quality in the offices.