tics by state-of-the-art solid phase extraction: mining
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TICs by State-of-the-Art SolidPhase Extraction: Mining the
Preliminary Results
ByR. Lee Lippincott Ph.D.
Judith Louis Ph.D., Gail Carter, Julia Barringer, Jessica Hopple,Robert Stiles, Brian Buckley Ph.D.
Field Study: Sites of Thirty-one WellsSampled
All 593Public CommunitySupply Wells in theCoastal Plain, withVOC SusceptibilityScores
The 16 pairs ofHigh/Low WellsSelected for Samplingin Year 2 of the Study
The 16 High/LowPairs of WellsSelected forSampling
FinalSusceptibilityRank shown foreach well
Public Community Water Supply Systems in the Coastal Plainwith both High and Low Final Susceptibility Ranks
An example of 2 pairs of High/Low Wells
950 feet
875 feet
NJDEP Source Water AssessmentProgram (SWAP)
Model Developed by NJDEP and USGS RelatingGroundwater Quality to Land Use Patterns
2337 Community Water Supply Wells in NewJersey
Wells Given a Score and Rating Based onSensitivity and Intensity of Use Factors
Goals of Study
1. Evaluate Analytical Methods for the Optimizationof Compound Recovery
2. Gather Data on the Contamination of the WellsSampled by NJDEP so that SWAP Model can beValidated
Previous Work
EPA 8270 and 525.2 Analyzes Water for Semi volatileOrganic Contaminants (SVOCs) by SPE-GC/ITMSMethod Detection Limits (MDLs) Lowered for PAHs,PCBs and Pesticides using Modified EPA 525.2 MethodField Tested Method on Water Treatment Plants in NewJerseyDetection of a Number of Unregulated Contaminants
C-18
DVB
Solid Phase Materials
Discovery Polymer
Analytical Instrumentation
Solid Phase Microextraction (SPME)
J. Chromatography A, 1996, 733, 143-157
FiberAgitationSalinityExtraction TimeExtraction TemperaturepHSampling Mode
Parameters to Optimize for SPME
Optimized SPME DirectExtraction Conditions
Fiber – 70μm CW/DVBSalinity – 10% NaClExtraction Time – 50 MinutesExtraction Temp – 45°CpH - Neutral
3 Fibers - 3 Methods
100μm PDMSpolydimethylsiloxane
70μm CW/DVBCarbowax-divinylbenzene
85μm PApolyacrylate
Phthalates
General SVOCs
Phenols
MethodsFibers
Absorption Vs. AdsorptionAdsorption: Surface Phenomena
Absorption: Diffusion PhenomenaSPME FiberSPME Fiber
Criteria for Selectingan Extraction
Method (SPE vs.SPME)
Cost/Time of Analysis
Background ContaminantsSample ConsumptionMethod Detection LimitsField Test
Background Contaminants:BreakingMethods into Components
SolventsGlasswareSPE Column HousingsSPE Sorbent Materialand Frits
FiberSampling VialsWaterSalt
SPE SPME
Most Frequently Detected SPMEArtifacts
Compound Source(s)1,9-Nonanediol Carbowax Phase of SPME FiberBis Substituted Compounds Epoxy Glue of SPME NeedleCyclodecanol SPME Vial or Crimp TopDibutyl Phthalate SPME Vial or Crimp TopIsopropyl Myristate SPME Vial or Crimp Top (Leached by Water)Isopropyl Palmitate SPME Vial or Crimp Top (Leached by Water(Z)-. 6,10-dimethyl-5,9-Undecadien-2-one SPME Vial or Crimp Top
1 0 1 5 2 0 2 5 3 0 3 5 4 0m i n u t e s
0
5
1 0
1 5
2 0
M C o u n t s
0
5
1 0
1 5
2 0
M C o u n t s
R I C a l l w a t e r b l a n k . s m s
R I C a l l w a t e r b l a n k . s m s
SPE Water Blank
SPME Water Blank
Relative Intensity of Blanks
Background Contaminants(Summary)
SPE – Artifacts are Mostly PlasticizersOriginating from Sorbent Material and Frits
SPME – Artifacts have a Wide Range of Sourcesand are Fiber Dependent
SPE has a Greater Number of Artifacts but inLower Concentrations
Method Detection Limits: SPME vs.USGS
CW/DVB MDLs (ppb) USGS RLs (ppb)bis (2-ethylhexyl) adipate 1.0 2000.0carbaryl 10.0 60.0butylated hydroxy toluene 1.0 80.0bisphenol A 1.0 90.0N,N-diethyltoluamide 1.0 40.0dieldrin 0.1 80.0cis-chlordane 0.1 40.0lindane 0.1 50.0tetrachloroethylene n.d. 30.0diazinon 1.0 30.0chlorpyrifos 1.0 20.0triphenyl phosphate 1.0 100.0methyl parathion n.d. 60.01,4-dichlorobenzene 0.5 30.0acetophenone n.d. 150.0bis (2-ethylhexyl) phthalate 0.5 2500.0diethyl phthalate 0.5 250.04-methylphenol 0.5 40.0
Environmental Science and Technology, 2002, 36, 1202
Compound Class Direct SPME SPEBrominated 35 1
Chlorinated 6 14
Phenols 14 12
Benzenes 11 3
PAHs 5 0
Phthalates 5 3
Alcohols 10 11
Ketones 17 8
Aldehydes 4 1
Number of Unique Analytes Detectedin Wells
Future Directions
Field Sampling of Wells In the Coastal Plain
Development of SPME-LC/MS Method
Investigation of Fibers that can Extract Analyteswith Extremely High or Low Log Kow Values
Data Mining ProcessEvaluate Blank Data for repetitive blankcontaminantsSort Blank Data and Sample Data setsCompare Levels of Method Blank Contaminationwith Sample ContaminantsEliminate Blank Constituents from SamplePreliminary Data
Data Prioritization ProcessLook for recurring contaminants in the wells
Evaluate the quality of the Mass Spectrometry
Determine Structure and plausibility of existencein the water column
Determine if you are observing a weathered orhydrolyzed product of another contaminant
O
Br
Br
Br
Br
Br
BrBr
Br
BrBr
O
Br
Br2,6-dibromo-4-methoxytoluene
O Br
1-bromo-4-ethoxy-benzene
FRAGMENTS OF PBDE’s ?
OR BROMINATED DBP’s ?
Br
2-bromo-m-xyleneBr
2-bromo-1,4-dimethyl Benzene
Br
2-bromo-1,3,5-trimethylbenzene
NH
N
Br
Br
Br3,4,5-tribromo-1H-Pyrazole
Br
Br
1,2-dibromo-1-methyl-cyclohexane
U.S. Environmental Protection AgencyPolybrominated Diphenyl Ethers (PBDEs) Project Plan
March 2006
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