Interlaboratory Study of Polychlorinated Biphenyl Congeners from Sediment Samples with High-Resolution and Low-Resolution Mass Spectrometry
Wayne J. Whipple, U.S. Environmental Protection Agency, Chicago, IL
Jaana M.H. Pietari, Exponent Inc., Bellevue, WA
Amanda T. Wroble, U.S. Environmental Protection Agency, Chicago, IL  

Maximizing Biodegradation Information of Oil Contamination in Soils using a 3 Dimensional Chromatography Approach
Debin Mao, Flemish Institute for Technological Research (VITO), Mol, Belgium
Richard Lookman, Flemish Institute for Technological Research (VITO), Mol, Belgium
Hendrik Van De Weghe, Flemish Institute for Technological Research (VITO), Mol, Belgium
Nicole De Brucker, Flemish Institute for Technological Research (VITO), Mol, Belgium
Ludo Diels, Flemish Institute for Technological Research (VITO), Mol, Belgium 

Arsenic and Thallium Data in Environmental Samples: Fact or Fiction?
Susan D. Chapnick, New Environmental Horizons, Inc., Arlington, MA
Leonard C. Pitts, Ph.D., Alpha Analytical, Mansfield, MA
Nancy C. Rothman, Ph.D., New Environmental Horizons, Inc., Skillman, NJ

Interlaboratory Study of Polychlorinated Biphenyl Congeners from Sediment Samples with High-Resolution and Low-Resolution Mass Spectrometry
Wayne J. Whipple, Ph.D.,  U.S. Environmental Protection Agency, Region 5 Chicago Regional Laboratory, 536 S. Clark St., ML-10C, Chicago, IL 60605, Tel: 312-353-9063, Fax: 312-582-5168, Email: whipple.wayne@epa.gov
Jaana M.H. Pietari, Exponent Inc., 15375 SE 30th Place, Bellevue, WA 98007, Tel: 425-519-8703, Email: jpietari@exponent.com
Amanda T. Wroble Ph.D., U.S. Environmental Protection Agency, Region 5 Chicago Regional Laboratory, 536 S. Clark St., ML-10C, Chicago, IL 60605, Tel: 312-353-9063, Fax: 312-582-5168, Email: wroble.amanda@epa.gov

The applicability of the performance based measurement (PBM) approach to the analysis of polychlorinated biphenyl (PCB) congeners was examined by an interlaboratory study that compared the performance of several determinative methods on a set of extracts from sediment samples contaminated with PCBs.  In this study, three extracts containing high, medium, and low levels of PCBs, and quality control samples were distributed to various laboratories for clean-up and analysis of 28 target PCB congeners by gas chromatography combined with high or low resolution mass spectrometric detection (HRMS or LRMS) based on each individual laboratory’s approved standard operating procedure.  Overall, comparable performance was observed for HRMS and LRMS analyses of PCB congeners present above 0.5 μg/kg in the quality control samples with most interlaboratory congener-specific relative standard deviations less than 25%.  Relatively consistent reporting was also observed for congeners present above 2.5 μg/kg in the PCB contaminated sediments, exhibiting similar interlaboratory, LRMS, and HRMS precision of 43-57%.  These results suggest the validity of the PBM approach for the determination of PCB congeners in medium to high level PCB contaminated samples.  Below the sample-specific thresholds, HRMS instrumentation is necessary to detect these lower concentrated congeners, although poor interlaboratory agreement of the reported concentrations is observed at this level.  

Maximizing Biodegradation Information of Oil Contamination in Soils using a 3 Dimensional Chromatography Approach

Student Presenter

Debin Mao, Flemish Institute for Technological Research (VITO), Boeretang 200, B-2400 Mol, Belgium, Dept. of Biology, University of Antwerpen, Universiteitsplein 1, B-2610 Wilrijk, Belgium, Tel: 0032(0)14335015, Fax: 0032(0)14319472, Email: debin.mao@vito.be
Richard Lookman, Flemish Institute for Technological Research (VITO), Boeretang 200, B-2400 Mol, Belgium, Tel: 0032(0)14335850, Fax: 0032(0)14321185 Email: richard.lookman@vito.be
Hendrik Van De Weghe, Flemish Institute for Technological Research (VITO), Boeretang 200, B-2400 Mol, Belgium, Tel: 0032(0)14335032, Email: hendrik.vandeweghe@vito.be
Nicole De Brucker, Flemish Institute for Technological Research (VITO), Boeretang 200, B-2400 Mol, Belgium, Tel: 0032(0)14335014, Email: nicole.debrucker@vito.be
Ludo Diels, Flemish Institute for Technological Research (VITO), Boeretang 200, B-2400 Mol, Belgium. Dept. of Biology, University of Antwerpen, Universiteitsplein 1, B-2610 Wilrijk, Belgium, Tel: 0032(0)14336924, Email: ludo.diels@vito.be 

GC/FID and/or GC/MS are commonly used for petroleum hydrocarbon analysis in soils. However, these techniques only provide limited information due to their insufficient separation power. Recently, we developed a new analytical method for detailed monitoring of petroleum hydrocarbon biodegradation in soils based on HPLC-GCXGC/FID^1,2,3,4. The new method (VITO-SOILCARE^TM) demonstrated its superiority to conventional GC-based methods with respect to predication of water solubility/migration risks, biodegradability and toxicological risks of oil contaminants.

We recently implemented HPLC-GCXGC/FID and GCXGC/ToF-MS as a "3D+3D" analytical technique for studying the aerobic biodegradation of (diesel) oil contamination in soils. The information obtained by the above analysis includes the biodegradability of each defined oil fraction, the effect of biodegradation on leaching potential of the remaining oil contamination, and the evolution of (eco)toxicological risk during and after biodegradation. A 20-week biodegradation experiment was conducted with both fresh and weathered oil contaminated soils. With HPLC-GCXGC/FID, the biodegradability of 10 hydrocarbon groups plus 15 representative individual hydrocarbons was obtained. We found that although nutrient amendment may increase TPH removal, it can pose an adverse effect on the reduction of toxicological risks and leaching potential. GCXGC/ToF-MS analysis results of the soil leaching water showed that various oxygenated hydrocarbons are produced during bioremediation. These compounds are observed in the leaching water together with low boiling point aromatic hydrocarbons at the early stages of biodegradation. The intermediate biodegradation metabolites were then further degraded at later stages of the experiment. In general, the leached compounds moved upward and rightward on the GCXGC color plots upon increasing biodegradation time, indicating that more polar and heavier compounds were formed as biodegradation proceeded. Acute ecotoxicity tests (plant seed germination and Microtox^®) were performed over time to give a direct indication of toxicological risk evolution and to assist interpretation of the chemical analysis results.

In conclusion, the "3D+3D" analysis technique provided comprehensive information regarding oil biodegradation in soils that can not be obtained by any other existing analytical technique. The information obtained can be vital not only for better understanding of oil aerobic biodegradation but also for developing environmentally acceptable concentration levels of petroleum hydrocarbons in bioremediated soils.

Reference

1. Mao D. et al., 2008. Journal of Chromatography A, 1179, 33-40.
2. Mao D. et al., 2009. Fuel, 88, 312-318.
3. Mao D. et al., 2009. Journal of Chromatography A, 1216, 1542-1527.
4. Mao D. et al., 2009. Journal of Chromatography A, 1216, 2873-2880. 

Arsenic and Thallium Data in Environmental Samples: Fact or Fiction?
Susan D. Chapnick, M.S., New Environmental Horizons, Inc., 2 Farmers Circle, Arlington, MA 02474, Tel: 781-643-4294, Email: s.chapnick@comcast.net
Leonard C. Pitts, Ph.D., Alpha Analytical, 320 Forbes Blvd, Mansfield, MA 02048, Tel: 508-822-9300, Email: lpitts@alphalab.com
Nancy C. Rothman, Ph.D., New Environmental Horizons, Inc., 34 Pheasant Run Drive, Skillman, NJ 08558, Tel: 908-874-5686, Email: nrothman_neh@comcast.net

Using case studies we present data in groundwater, soil, and sediment that demonstrate severe matrix effects on the accuracy of metals results with a focus on Arsenic and Thallium. An EPA Office of Technical Standards Alert estimated that environmental data reported using Inductively Coupled Plasma Spectrometry (ICP-AES, EPA Method 6010B) has a false positive rate for Arsenic of 25-50% and that 99.9% of Thallium detected results were false positives.  Though this does not seem to be widely known in the environmental community, we have corroborated false positive and high biased results for these metals.  Soil analyses for a site assessment in New York showed detected metals concentrations that approached or exceeded the applicable regulatory soil cleanup objectives of 13 mg/Kg for Arsenic and 2 mg/Kg for Thallium.  Based on site history, these results were not expected.  Re-analysis using ICP coupled with a mass spectrometer as the detector (ICP-MS, EPA Method 6020A), confirmed all Thallium results were false positives and all Arsenic results were significantly below the soil cleanup criteria; concluding no action was required for soil remediation for these two metals.  At a Superfund site in Massachusetts, Thallium was detected in groundwater up to 21.6 µg/L using ICP-AES.  Re-analysis by ICP-MS for all samples reported Thallium as non-detect below the applicable regulatory level.  ICP-MS is usually a more definitive, sensitive, and accurate method of analysis compared to ICP-AES; however, this is not always the case as we will show using data from a Superfund site where interferences of non-metallic elements in the samples caused biased high results for Arsenic using ICP-MS.  We provide information on causes of these effects and recommendations to obtain accurate metals data for site assessment, risk characterization, and remedy selection.

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