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PCBs in Older Buildings: Measuring PCB Levels in Caulk and Window Glazing Materials in Older Buildings
Lantis I Osemwengie1, Jade Morgan1
1US Environmental Protection Agency, National Exposure Research Laboratory, Exposure Methods and Measurement Division, P.O. Box 93478, Las Vegas, NV 89193-3478, USA.
Abstract:
A method for the determination of polychlorinated biphenyls (PCBs) in caulk and glazing materials was developed and evaluated by application to a combination of 36 samples of caulk and glazing materials, from four schools in the northeastern area of the United States. Quality control analysis showed a range of 45 to 170% for spike recovery from the various samples and a range of 10.9 to 20.1% difference in precision among replicates. The result for the samples analyzed showed that three of the four schools sampled contained caulking and glazing materials with levels of PCBs >50 microg/g (range 54.6 microg/g to 445,000 microg/g). Across the four schools, 24% of collected caulk and glazing samples contained elevated PCB levels relative to the U.S. Environmental Protection Agency's (EPA) bulk product waste criterion of 50 microg/g under "The Frank R. Lautenberg Chemical Safety for the 21st Century Act." The PCBs determined in the samples, exhibited characteristic chromatographic patterns similar to those of Aroclors 1242, 1248, 1254, 1260, 1262, and a 1016/1254 mix.
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