Daniel B. Cardin and Victoria L. Noad

The need for accurate monitoring of SVOCs in water samples using methods such as US EPA Method 8270 continues to grow in importance as the com- prehension of their adverse effects on human health evolves. Improvements in analytical technology for accurate determination down to sub-PPB levels is critical to obtain the most comprehensive monitoring possible. Current techniques for extraction of base/neutral/acid SVOCs include solvent extraction and separatory funnel extraction, however these methods require many steps and environmentally unfriendly solvents. Additionally, there are many analytical challenges due to matrix interferences, contamination, and the broad range of chemical properties. A new solvent-free automated technique for extracting SVOCs in water using Vacuum Assisted Sorbent Extraction (VASE) paired with GCMS is presented. VASE allows reliable extraction with minimal matrix effects due to the high phase ratio and surface area of the adsorbent. VASE is a powerful extraction technique which places a sample vial under vacuum in the presence of a 70mg adsorbent cartridge (Sorbent Pen) to effect near exhaustive extractions of GC compatible compounds. After the vacuum source is removed, the vial remains under vacuum causing transfer to the adsorbent faster than at atmospheric or higher pressures. Repeated heating and cooling of the sample creates a boiling action in a closed system which effectively transfers even the heaviest SVOCs and recovery surrogate standards into the adsorbent. Sample injection is performed with a thermal desorption unit fitted into a GC injection port. Extracted compounds remain near the front of the adsorbent ensuring their quantitative recovery. Calibration curves for SVOCs such as phthalates, pesticides, PCBs, and PAHs out to 6-rings and results from surface and waste water samples are presented. Data reveals both the reproducibility and lack of carryover achieved by this new technique resulting in accurate analysis of SVOCs.

Chairs: Manuel Miró and Emanuela Gionfriddo

Thursday, June 21st
12:45-1pm