Emission characteristics of VOCs from athletic tracks

Dynamic and flow-through flux chambers are convenient tools for field measu rements of gas or VOC emission flux from solid surfaces in the field. This study was undertaken to collect on site and quantify the emissions of volat ile organic compounds (VOCs) released from athletic running tracks. Three t ypical types of tracks, one synthetic rubber and two tracks (types I and Ui ) consisting mainly of polyurethane, were studied. They were all installed with adhesives and backings, both of which contributed significant amount o f VOCs. VOCs released from the track surface were collected with a flux cha mber and subsequently analyzed by a gas chromatograph/mass spectrometer (GC /MS). Also, for each track and at each selected time the emission flux and mass emission were measured on site under outdoor conditions over a period of 40 min. GC/MS analyses show that the VOCs emitted include 2-methyl furan , butanal, methyl ethyl ketone, benzene, heptane, methyl isobutyl ketone, t oluene + octane, hexanal, nonane + ethylbenzene, xylenes + styrene, propyl benzene, decane, 1,3,5-trimetlhyl benzene, 1,2,4-trimethyl benzene, 1,2,3-t rimethyl benzene and undecane. Of these, hexanal was the common and princip al compound for all three types of tracks. 2-Methyl :Furan and methyl isobu tyl ketone were the characteristic compounds for the synthetic rubber and t he type II of polyurethane tracks, respectively. In the field studies, no u nique compounds were found in the type I of polyurethane tracks. For each o f these three types of tracks the total-VOCs emission flux was correlated t o the track age and track surface temperature. The results of multiple regr ession analysis showed good correlation. The type II polyurethane track had the highest decay rate, while the synthetic rubber track had the lowest de cay rate. Two years after the track installation, the VOC concentrations me asured at 1.5 m above the track, the breathing height of school children, w ere not significantly higher than the background levels. (C) 1999 Elsevier Science B.V. All rights reserved.