W11 AM Environmental Chemical Forensics
Wednesday, 16 November 2005: 8:00 AM - 11:40 AM in 343-344

(JOH-1117-822088) Distinguishing Between Two Types of Aroclor 1254: Considerations for Environmental Forensics Investigations.

Johnson, G¹, Hansen, L², Hamilton, M³, Hermanson, M⁴, Horsak, R⁵, O'Keefe, P⁶, ¹ University of Utah, Salt Lake City, UT, USA² University of Illinois, Urbana, IL, USA³ Axys Analytical Services, Ltd., Sidney, BC, Canada⁴ University of Pennsylvania, Philadelphia, PA, USA⁵ 3TM International, Inc., Houston, TX, USA⁶ NY State Dept. Health, Albany, NY, USA

ABSTRACT- Two distinct variants of Arolcor 1254 (A1254) were produced by Monsanto. The "typical" variant was produced through the early 1970s and accounts for the vast majority of A1254 production. It has been reported in the literature that the "late-production" variant was sold from 1974 through 1976. In this paper, we present information that pushes that estimated production start-date back to at least 1972. It may predate 1972, but if so, it is unlikely to have been produced before 1971 because its production was linked to the Aroclor 1016 production process which began that year. Late production A1254 is also notable because it has higher proportions of both coplanar (dioxin-like) PCBs and polychlorinated dibenzofurans, as compared to the more typical A1254 variant. The congener patterns of the two A1254 variants are distinct, and are readily recognizable when encountered in environmental media. While late-production A1254 accounts for a small percentage of total production, it can be and has been encountered in environmental forensics field investigations. We present a litigation related case study where the late-production variant was recognized in industrial site soils, residential soil, and tree bark.

Key words: Aroclor 1254, Polychlorinatd Biphenyls, Environmental Forensics