Abstract

This study investigated the polybrominated diphenyl ether, PBDE, congeners present in the indoor atmosphere of computer classrooms with differing exposure sources. A total of six air samples were obtained from three classrooms. These samples were analyzed by high-resolution gas chromatography and high-resolution mass spectrometry, and the total PBDE concentration ranged from 34.4 - 488.7 pg/m³. In one classroom without decoration, measurements were taken with the computers on in one day (one sample) and with the computers off in another day (one sample). When computers were switched on, the indoor total PBDE concentration was 10-fold that when they were switched off. When the computer power was on, the majority of the PBDE congeners found in two classrooms without decoration were of high molecular weight, i.e., on average, BDE209 (24.8%), BDE203 (12.8%), BDE183 (9.2%), BDE196 (7.4%) and BDE207 (6.3%); however, when the power was off in one classroom without decoration, the majority were of low molecular weight, i.e., BDE47 (18.2%), BDE17 (12.9%), BDE15 (11.3%), BDE28 (11.1%) and BDE99 (6.4%). The five most abundant PBDE congeners found in one decorated classroom where all computers were switched on (two samples) were BDE15 (30.7%), BDE7 (13.2%), BDE209 (10.1%), BDE28 (8.1%) and BDE17 (5.5%), indicating that materials used for decoration and PUF-containing chairs are a major source of di-BDE and tri-BDE. These two homologs constituted 57.4% of the total PBDE concentrations. This study confirmed that computer equipment, interior decoration and PUF-containing chairs, and whether the power is switched on or off, significantly affects the PBDE concentration.

Key words: Polybrominated diphenyl ethers, indoor, PBDE congeners.