Emerging Chemicals of Concern for the Environment by SPE coupled with HPLC and HPLC/MS/MS Detection
The USGS has identified 95 organic wastewater contaminants (OWC’s) of concern (Kolpin et al. 2002). In this study, 80 percent of streams sampled contained measurable levels of OWC’s. This list consists of many new classes of organic compounds not amenable to the more common EPA GC and GC/MS standard analytical methods. These new classes of compounds include veterinary and human antibiotics, human drugs, industrial and household hazardous wastewater and multiple classes of hormones, which are generally larger and less volatile than analytes found on current EPA method lists. Reversed phase HPLC analysis with a polar mobile phase is particularly suitable to analyzing large molecules that exhibit low volatility. HPLC methods have been developed by Columbia Analytical Services in Kelso for the analysis of a wide range of these compounds utilizing UV and fluorescence detectors. Methods already developed include a number of estrogens and caffeine and its metabolites.
Solid phase extraction (SPE) allows concentration of analytes of interest with minimal use of organic solvent and decreased co-extraction of background components due to its selectivity. By utilizing SPE and clean-up techniques coupled with conventional HPLC detectors, sub ppb detection limits have been obtained (i.e. estrogens 0.2 μg/L). CAS has recently ordered a Thermo Electron TSQ Quantum HPLC/MS/MS for analysis of pharmaceutical and environmental samples, including the emerging chemicals of concern. As methods are transferred from conventional HPLC detectors to HPLC/ MS/MS significant reduction in background will lead to decreased detection limits ranging from 10-100 times lower than conventional HPLC detectors.
Reference: Kolpin, D., Furlong, E., Meyer, M., Thurman, E., Zaugg, S., Barber, L., Buxton, H. 2002. Pharmaceuticals, Hormones, and other Organic Wastewater Contaminants in U.S. Streams, 1999-2000: A National R e c o n n a i s s a n c e . Environmental Science and Technology 36:1202-1211.