Source identification of trichloroacetic acid with preparative capillary gas chromatography and accelerator mass spectrometry
For Paweł
Acknowledgements
S S S S S S S
Contents O S S S S S S O
S S S O S O O S S S S S O S
O O S S S
List of abbreviations
S
S
N,N’
S S S
O
S
S
S
S
S
S S
S S S
S
S
S
t
S
O
O
O
o
S S
S S
S S
S S
SO
O
O O S
Introduction
1. Introduction …den Menschen und die Umwelt vor schädlichen Einwirkungen gefährlicher Stoffe und Zubereitungen zu schützen, insbesondere sie erkennbar zu ma- chen, sie abzuwenden und ihrem Entstehen vorzubeugen.“
S S O Introduction
S
µ O
Objectives of the thesis
2. Objectives of the thesis S S
µ
µ µ S S
TCA in the environment
3. TCA in the environment 3.1 Application and sources of TCA O S O O
•
• • • O • O
TCA in the environment
•
S
3.1.1 Formation of TCA from tetrachloroethene µ µ O O O
TCA in the environment
OO O O O O
O O O O
Fig. 1: Formation of TCA from tetrachloroethene in the atmosphere.
3.1.2 Formation of TCA from 1,1,1-trichloroethane µ O O O O TCA in the environment
O
O O
O O
OO O O O
O O O O O O O O
Fig. 2: Formation of TCA from 1,1,1-trichloroethane in the atmosphere.
3.1.3 Suggested natural formation of TCA
± S Caldariomyces fumago S
TCA in the environment
O
O
O
Fig. 3: Biotic formation of TCA.
O O O O O O O O O O
O O O O O
Fig. 4: Speculative formation of TCA and chloroform from resorcinolic substances (Hoekstra et al., 1999b).
O
O O → O O
TCA in the environment
Methylocystis S
O O O O O
Fig. 5: Hypothetical pathways of trichloroethene degradation by Methylocystis sp. (Saeki et al., 1999).
S 3.2 Environmental concentrations of TCA O TCA in the environment
O S
Environmental compartment Concentrations
S
µ
µ
S S S µ
µ
S µ
µ
Tab. 1: TCA concentrations in environmental compartments.
TCA in the environment
3.3 Physico-chemical properties of TCA
Property Trichloroacetic acid
S
O
O S S S
O
Tab. 2: Physico-chemical properties of TCA.
TCA in the environment
3.4 Toxicity of TCA 3.4.1 Ecotoxicology S S S S Chlorella pyrenoidosa O µ Pinus sylvestris
µ µ O
TCA in the environment
3.4.2 Mammalian toxicity O O O S S
≥ O
TCA in the environment
O 3.5 Analytical methods for haloacetate analysis in the environ- ment 3.5.1 Gas chromatography/electron capture detection (GC/ECD) O
µ
µ o
µ
µ TCA in the environment
O 3.5.2 Gas chromatography/mass spectrometry (GC/MS) S S S
S µ S µ S O S
µ S µ S 3.5.3 Capillary electrophoresis (CE) S
TCA in the environment
µ S S t 3.5.4 Liquid chromatography/mass spectrometry (LC/MS) S S S S S
µ S
µ
µ S S S S S S
TCA in the environment
S S 3.5.5 Supported-liquid-membrane micro-extraction/high-performance liquid chromatography/UV detection (SLMME/HPLC/UV) S
µ S 3.5.6 Ion chromatography (IC)
µ
µ
S µ
S µ
TCA in the environment
S 3.5.7 Sensor based on molecularly imprinted polymer (MIP) membrane
µ S 3.6 Derivatization methods 3.6.1 1-Pentafluorophenyl-diazoethane (PFPDE) S O
TCA in the environment
O O O O O O
O O
Fig. 6: Derivatization of haloacetates with PFPDE and fragmentation in GC/NCI/MS (Hofmann et al., 1990). R = X 3C, X 2HC, XH 2C; X = Cl, Br, I.
3.6.2 2,4-Difluoroaniline (DFA) N,N’
µ O O 3.6.3 Acidified methanol O S
TCA in the environment
O
O O O O O O O O O O O O O
O
O O O O O O O O
Fig. 7: Derivatization of haloacetates with acidic methanol (Urbansky, 2000). R = X 3C, X 2HC, XH 2C; X = Cl, Br, I.
3.6.4 Diazomethane S O O S
O O O
O O O O
Fig. 8: Derivatization of trichloroacetate with diazomethane.
TCA in the environment
3.6.5 Dimethylsulfate
O SO
O SO
SO O S
µ 3.6.6 Pentafluorobenzyl bromide (PFBBr)
O S S
O O O
Fig. 9: Derivatization of trichloroacetate with PFBBr (Sinkonnen et al., 2000).
14 C isotope (radiocarbon)
4. 14 C isotope (radiocarbon) 4.1 Origin and distribution of radiocarbon O → O → → γ → O O O → O O ˙ ˙ O O → O S
14 C isotope (radiocarbon)
O
Fig. 10: Long-term atmospheric 14 C observations in the northern (solid lines) and southern (dashed lines) hemispheres (Manning et al., 1990).
→ β
14 C isotope (radiocarbon)
4.2 Environmental science application of the radiocarbon method
•
• • • • • • 4.3 Equipment used for radiocarbon measurement 4.3.1 Gas proportional counting 14 C isotope (radiocarbon)
S 4.3.2 Liquid scintillation (LS) counting S O
14 C isotope (radiocarbon)
4.3.3 Accelerator mass spectrometry (AMS) S S O
• • • •
S O S
S O OO O O O O O O S S
O
14 C isotope (radiocarbon)
O S
Fig. 11: Schematic diagram of an AMS gas ion source: a) pumping and cryogenic transfer of CO 2 to reservoir; b) measurement; V1, V2: valves, LN: liquid nitrogen (Kretschmer et al. 2004).
O
O
µ µ S S S
14 C isotope (radiocarbon)
S
S S
Fig. 12: Scheme of MS and AMS (M-mass, E-energy, q-charge, kV-kilovolt, MV-megavolt) (Tuniz et al., 1998).
S
• • • •
•
• • S S S S S 14 C isotope (radiocarbon)
S S S S S S S O S O S O S O S S
Kovats retention index
5. Kovats retention index
log t ' − log t ' I st. ph. (T) = 100 Rs Rz +100z s ' − ' log tR(z+ )1 log tRz
Kovats retention index
t − t I st. ph. =100n Rs Rz +100z TPGC,s − tR(z+n) tRz
O O
Experimental work
6. Experimental work 6.1 Chemicals and equipment 6.1.1 Chemicals
• S • S • ≥ • • S
• ≥ • ≥ • • ≥ S • ≥ S • • • S S • • • • • ≥ • -t S • •
• ≥ • • S Experimental work
• S • ≥ • S • ≥ • S • ≥ • S • S 6.1.2 Equipment S S S
Experimental work
Fig. 13: Gas chromatograph with large volume injector and cold injection system: 1 - autosampler, 2 - cold injection system, 3 - gas chromatograph, 4 - capillary column, 5 - flame ionization detector, 6 - preparative fraction collector, 7 - analyte traps, 8 - cooling medium (liquid nitrogen), 9 - waste trap.
µ
µ µ
Experimental work
S S S S S S
Fig. 14: Schematic diagram of an AMS facility.
S
Experimental work
O O
• S • S • S • • • S • • S • O S • • S • • S • S 6.2 Sampling site selection O S O
µ O µ Experimental work
The Netherlands, October 1999 Scandinavia, October/November 1999
0.5 0.7
g/kg] 0.6 µ µ µ µ g/kg] 0.4 Göteborg, Sweden µ µ µ µ 0.5 Utrecht Oslo, Norway 0.3 Rotterdam 0.4 0.3 0.2 0.2 0.1 0.1 TCA-concentration [ [ TCA-concentration 0.0 TCA-concentration [ 0.0 0.1 0.3 1.0 0.1 0.3 0.7 Depth [m] Depth [m]
Italy, November 1999 United Kingdom, November 1999
0.7 1.4
g/kg] 1.2
0.6 g/kg] µ µ µ µ µ µ Venice µ µ 0.5 1.0 Rome Notthingam 0.4 0.8 Glasgow 0.3 0.6 0.2 0.4 0.1 0.2 TCA-concentration[
TCA-concentration[ 0.0 0.0 0.1 0.3 0.7 0.1 0.3 0.8 Depth [m] Depth [m] Germany, October 1999
14
g/kg] 12 µ µ µ µ 10 Freudenstadt 8 Kiel 6 4 2
TCA-concentration [ [ TCA-concentration 0 0.1 0.3 0.6 Depth [m]
Fig. 15: TCA-concentrations in forest soil in different sampling places in Europe: the Netherlands, Scandinavia, Italy, United Kingdom and Germany in 1999 (data from Peters, 2000).
Experimental work
µ µ µ µ
O S S S
Fig. 16: TCA concentrations in spruce needles in LfU-observational network from 1992 to 1995 (Frank et al., 1997).
O
µ µ S O O O O
Experimental work
O
µ µ S ⋅ = mC M TCA mB 2 ⋅ cTCA ⋅ M C
S µ
µ
O O
Experimental work
Maria-Bildhausen Oberthulba
Altmugel
Fig. 17: Sampling sites and meteorological station Maria-Bildhausen .
Fig. 18: Rainfall during the month prior to sampling (Maria-Bildhausen, www.stmlf- design2.bayern.de).
Experimental work
6.3 Cleaning of glassware and PP-equipment, removal of con- taminants
O SO
O O 6.4 Quantitative determination of TCA in soil
S S
Experimental work
S
S S O
S
S O
SO
SO
Fig. 19: Sample preparation for GC/NCI/MS analysis.
O S
µ
O S
O S
SO
Experimental work
µ SO
µ µ
SO S S
µ
O µ
SO
Experimental work
Gas chromatography
µ S S
µ
Mass spectrometry
µ S S S
Tab. 3: Gas chromatographic and mass spectrometric conditions for quantitative de- termination of TCA in soil.
6.5 Optimization of soil extraction process
6.5.1 Selection of extraction agent
O Experimental work
O
O
O
SO 6.5.2 Optimization of extraction time
O
O O
O
SO
Experimental work
6.5.3 Optimization of the number of extraction steps
O
O
O
SO 6.6 Calculation of Kovats index O S
O O µ µ O
Experimental work
Gas chromatography
S
µ S
Tab. 4: Gas chromatographic conditions for Kovats index determination.
µ 6.6.1 Soil sample preparation O
O
O
O SO
O
O
O
SO
Experimental work
O SO
SO
O
O O µ 6.7 Identification of co-eluting compounds O S
Experimental work
Gas chromatography
µ S S
µ
Mass spectrometry
µ S S S O
Tab. 5: Gas chromatographic and mass spectrometric conditions for identification of co-eluting compounds.
6.8 Isolation of TCA from soil 6.8.1 Soil sample preparation O
O
O
Experimental work
S S
O SO
O O
SO O
O
O SO
O
SO
SO
Experimental work
S
S S O
O SO
O SO
O O
O O
SO
O SO
O
O
O
Fig. 20: Sample preparation for preparative gas chromatography.
Experimental work
6.8.2 Blank sample preparation
O 6.9 Preparative capillary-gas chromatography (PC-GC) S O 6.9.1 PC-GC separation O
µ S
µ
O
µ S
O Experimental work
O
Gas chromatography
S
µ S S
µ S
Cold injection system
µ S S S
Preparative fraction collector
Tab. 6: Gas chromatographic conditions for preparative separation. Experimental work
6.9.2 Purification of TCA in soil extracts
O µ O
O µ µ
O µ 6.10 Sample preparation for AMS O O
O
Fig. 21: A modified quartz U-trap with one constriction on the shorter arm and two constrictions on the longer one.
Experimental work
O
O
O
O
O O
O
Fig. 22: High vacuum system used for CO 2 recovery and measurement after combustion: C1 - samlpe trap cracker, DIA - dry ice/acetone slurry, EM - electronic manometer, LN - liquid nitrogen, T1-T3: traps, T4: gas-tight cold-finger, V1-V6: valves (Hasan, 2002). Experimental work
Fig. 23: Sample trap cracker (Hasan, 2002).
O S
O S
Results and discussion
7. Results and discussion 7.1 Quality assurance 7.1.1 Limit of detection, limit of quantification, precision S
µ µ µ µ 7.1.2 Total error calculation Results and discussion
7.1.3 Repeatability S
µ S
µ S 7.1.4 Sample trapping efficiency
µ S S
O O µ
Results and discussion
14
12
10
8 y = 0.623x - 0.320 R2 = 0.9989
6 arbitrary units arbitrary
4
2
0 0 5 10 15 20 25 TCA-OMe [ µµµg]
Fig. 24: Calibration curve for TCA-OMe on a semi-polar column coated with 1.0 µm d f 50 %-methyl-50 %-phenyl-polysiloxane, CP-Sil 24 CB, 30 m x 0.53 mm i.d.; 40 °C, 2.3 min isotherm; 10 °C min -1 to 240 °C; 26 min isotherm.
µ µ
O O O
µ µ O µ µ
µ O µ µ
µ S O
Results and discussion
O 7.1.5 Combustion efficiency
µ O
O O
O
Sample Temperature [°C] Recovery [%]
Tab. 7: Sample recoveries applying a combustion temperature of 600 °C and 900 °C, respectively.
S
Results and discussion
7.2 Quantitative determination of TCA in soil O
TCA concentration Water content Soil pH [ g/kg dw] [%] µµµ mean value, n = 3 O O
Tab. 8: Water content, pH values, and TCA concentration in soil samples taken in Oberthulba and Altmugel on 5 June 2002 and 11 June 2002, respectively; n - number of analyses.
O
µ
Results and discussion
OO OO
Fig. 25: GC/NCI/MS (SIM) chromatogram of a soil extract with a content of 2.6 pg TCA and 6.1 pg 2,3-DCPA in one injection; 60 °C, 1.5 min isotherm; 25 °C min -1 to 240 °C; 1.3 min isotherm.
7.3 Optimization of soil extraction process 7.3.1 Selection of extraction agent
O S
O µ µ 7.3.2 Optimization of extraction time S
Results and discussion
Extraction time TCA concentration [ µµµg/kg] [h] mean value, n = 3
Tab. 9: TCA concentrations in samples extracted for 1, 2, and 3 hours, respectively (n - number of analysis).
7.3.3 Optimization of the number of extraction steps
TCA [ng] in extract Extraction step % of TCA extracted from 20 g soil sample
Tab. 10: TCA content obtained in consecutive extraction steps.
Results and discussion
7.4 Calculation of Kovats index O
O
Fig. 26: Chromatogram of 100 µL of a standard solution of 10.7 mg/L commercial TCA-OMe in Et 2O and 13.0 mg/L commercial n-paraffins C9 - C12, mixed in a ratio 1:1 and separated on an apolar column coated with 1.5 µm d f 95 %- methyl-5 %-phenyl-polysiloxane, CP-Sil 8 CB, 60 m x 0.53 mm i.d.; 80 °C, 70 min isotherm.
µ O
Retention time Retention value ’ Compound ’ log (t R) tR [s] t R = t R – t 0 O
Tab. 11: Retention times, retention values and their logarithms of some n-paraffins ’ and TCA-OMe; t R - retention time, t R - retention value, t 0 - dead time of the column.
O
Results and discussion
3 − .2 93 I − 80°C =100 +100 ⋅9 TCA OMe () .3 25 − .2 93 ° = ITCA−OMe (80 C) 922 O
O
O
Fig. 27: Chromatogram of 100 µL soil sample mixed in a ratio 10:1 with a 1:1 solution of 10.7 mg/L commercial TCA-OMe in Et 2O and 13.0 mg/L commercial n-paraffins C9 - C12 separated on an apolar column coated with 1.5 µm d f 95 %-methyl-5 %-phenyl-polysiloxane, CP-Sil 8 CB, 60 m x 0.53 mm i.d.; 80 °C, 70 min isotherm.
O S 7.5 Identification of co-eluting compounds O S
Results and discussion
Fig. 28: GC/EI/MS (TIC) chromatogram of soil sample; 30 °C, 3 min isotherm; 3 °C min -1 to 100 °C; 10 °C min -1 to 240 °C; 10 min isotherm.
O S O
O
Fig. 29: GC/EI/MS (SIM) chromatogram of soil sample, ions with m/z ratio of 117 and 119 are monitored; 30 °C, 3 min isotherm; 3 °C min -1 to 100 °C; 10 °C min -1 to 240 °C; 10 min isotherm.
O O O Results and discussion
S 7.6 Sample preparation for preparative isolation S
Bag Water content Bag Water content TCA pH TCA [ µµµg/kg] pH number [%] number [%] [µµµg/kg]
Tab. 12: Water content, pH values, and TCA concentration in soil samples taken in Oberthulba on 25 July 2002.
µ S Results and discussion
7.7 Preparative capillary-gas chromatography 7.7.1 PC-GC separation
Fig. 30: Chromatogram of 75 µL of soil extract separated on a column coated with 1.5 µm df 95 %-methyl-5 %-phenyl-polysiloxane, CP-Sil 8 CB, 60 m x 0.53 mm i.d.; 40 °C, 2.3 min isotherm; 7 °C min -1 to 260 °C; 45 min isotherm; fraction between 16.6 and 17.2 minutes is collected for the second preparative separation (figure 31).
O
Results and discussion
O ↓↓↓
Fig. 31: Chromatogram of a fraction containing TCA-OMe collected on an apolar column, re-injected and separated on a semi-polar column coated with 1.0 µm df 50 %-methyl-50 %-phenyl-polysiloxane, CP-Sil 24 CB, 30 m x 0.53 mm i.d.; 40 °C, 2.3 min isotherm; 10 °C min -1 to 240 °C; 26 min isotherm.
O
O
Results and discussion
Fig. 32: Chromatogram of 75 µL of soil extract separated on a column coated with 1.0 µm df 50 %-methyl-50 %-phenyl-polysiloxane, CP-Sil 24 CB, 30 m x 0.53 mm i.d.; 40 °C, 2.3 min isotherm; 10 °C min -1 to 240 °C; 26 min isotherm; fraction between 8.2 and 8.7 minutes is collected for the second preparative separation (figure 33).
O ↓↓↓
Fig. 33: Chromatogram of a fraction containing TCA-OMe collected on a semi-polar column, re-injected and separated on an apolar column coated with 1.5 µm df 95 %-methyl-5 %-phenyl-polysiloxane, CP-Sil 8 CB, 60 m x 0.53 mm i.d.; 40 °C, 2.3 min isotherm; 7 °C min -1 to 260 °C; 45 min isotherm.
Results and discussion
7.7.2 Purification of TCA in soil extracts O ↓↓↓
O ↓↓↓
Fig. 34: a) Chromatogram of 75 µL soil extract injected on 95 %-methyl-5 %-phenyl- polysiloxane, 60 m x 0.53 mm i.d., 1.5 µm df; 40 °C, 2.3 min isotherm; -1 7 °C min to 260 °C; 45 min isotherm; b) Chromatogram of 125 µL of a fraction separated on an apolar column, re-injected on 50 %-methyl-50 %- phenyl-polysiloxane, 30 m x 0.53 mm i.d., 1.0 µm df; 40 °C, 2.3 min isotherm; 10 °C min -1 to 240 °C; 26 min isotherm. In both chromatograms lines indicate the collected fractions.
O
Results and discussion
O
O
O O
µ µ
• S
• • •
• • O 7.7.3 Blank sample O
O
Results and discussion
O ↓↓↓
Fig. 35: a) Chromatogram of 75 µL blank sample injected on 95 %-methyl-5 %- phenyl-polysiloxane, 60 m x 0.53 mm i.d., 1.5 µm df; 40 °C, 2.3 min isotherm; -1 7 °C min to 260 °C; 45 min isotherm; b) Chromatogram of 125 µL of a fraction separated on an apolar column, re-injected on 50 %-methyl-50 %- phenyl-polysiloxane, 30 m x 0.53 mm i.d., 1.0 µm df; 40 °C, 2.3 min isotherm; 10 °C min -1 to 240 °C; 26 min isotherm. In both chromatograms lines indicate the collected fractions.
7.8 AMS analysis
O ⋅ pCO V m = .4 951 mg 2 c 104 mbar ⋅ mL
O
Results and discussion
O
14C 14C 14C = − 13 13 13 C Corr C Sample / S tan dard C Graphite
PMC
mass [mg]
Fig. 36: PMC values for 14 C-free carbon depending on the sample mass (Uhl, 2004).
Results and discussion
O δ 13C 13C − 12 12 C C δ 13 Sample PDB 0 CSample = ⋅ 1000 00 13C 12 C PDB δ O δ δ δ
14C 14C = 1− δ 13C + .0 025 13 13 []()Sample C CorrSample C Sample
14C 14C = .0 746 1− δ 13C + .0 025 13 13 []()S tan dard C CorrS tan dard C S tan dard O δ Results and discussion
14C/13C PMC = ( )CorrSample ⋅100 0 14C/13C 0 ()CorrS tan dard O
O
Results and discussion
13 Sample name Notes PMC PMC error [%] δδδ C Mass [ µµµg]
O
O
O
S O
O
Tab. 13: PMC values of calibration standards, 14 C-free graphite, and those of sam- ples determined in the present thesis, all obtained by AMS measurement (Ox II - oxalic acid with PMC mean value of 134.06, Ox 50 % - oxalic acid with PMC value of 49.58, IAEA-C5 - International Atomic Energy Agency wood standard).
O O Results and discussion
O S
Results and discussion
S
Conclusions
8. Conclusions
O S S
µ
µ
µ µ S
µ µ Conclusions
O S S O O S O O S O O O
Conclusions
O
Summary
9. Summary S S
µ S O
µ S Summary
µ S O S S O O
Zusammenfassung
10. Zusammenfassung S S
µ O S S S S S
µ S Zusammenfassung
µ S S O O S S S S S O O
References
11. References Chemosphere 52 Fresenius Journal of Analytical Chemistry 365 S Journal of Chromatography 101 Soil Biology and Biochemistry 25 S Environmental Science & Technology 37 Journal of Chromatography A 1047 S S S O
± Chemical Physics Letters 221 S References
S Water Research 32 S S S Environmental Science & Technology 34 Handbook of derivatives for chromatography S Water, Air, and Soil Pollution 101 Trichloroacetic acid / Sodium trichloroacetate S n Journal of Chromatography A 842 S The Journal of Chemical Physics 66 Atmospheric Environment 32 Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 123
References
Pestizide im Boden Chromatographia 54 Analytical Chemistry 68 S S S Analytical Chemistry 72 Trichloroacetic acid in the environment: Science dossier S Chemosphere 52 Environmental Pollution 124 Nachrichten aus Chemie, Technik und Laboratorium 36
Atmospheric environment 23
References
O Fresenius Journal of Analytical Chemistry 333
Atmospheric environment 24A S Zeitschrift für Umweltchemie und Ökotoxikologie 2 S Journal of High Resolution Chromatography 13 Ambio 20
Zeitschrift für Umweltchemie und Ökotoxikologie 3 Chemosphere 23 S S S Annales Botanici Fennici 29 S Environmental Science & Pollution Research 1
References
S Journal of High Resolution Chromatography 18 Monitoring des prioritären Altstoffs Trichloressigsäure (TCA) und anderer Halogenessigsäuren in Nadelproben aus dem Standortfichtenmeßnetz des LfU. S Analytical Chemistry 75 S S S S Radiocarbon after four decades, an interdisciplinary perspective S S Bestimmung von Halogenacetaten mittels LC-ESI-MS/MS S Environmental Science & Pollution Research 3 S Chemosphere 33 S Journal of Chromatography 219
References
S Environmental Pollution 130 Radiocarbon analysis of trace environmental chloroacetates by preparative capillary gas chromatography and accelerator mass spectrometry S O Environmental Toxicology and Chemistry 17 S O S Journal of High Resolution Chromatography 21 S Environmental Science & Technology 37 Chemisches Zentralblatt Journal of Chromatography A 997 Method 552:0: Determination of haloacetic acids in drinking water by liquid-liquid extraction, derivatization, and gas chromatography with electron capture detection S Chemosphere 38
References
Chemosphere 38 Chemosphere 52 S O Journal of Chromatography A 508 S S Atmospheric Environment 33 S Chemosphere 30 S The Science of the Total Environment 180 S Atmospheric Environment 32 Environmental Science & Technology 5 Halogenierte Essigsäuren in der Umwelt
References
Ullman’s Encyclopedia of Industrial Chemistry S O Journal of Chromatography 244 S S Journal of Chromatography A 1055 S S Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 123 Acta Physica Polonica B 31 S S Investigation of the origin of environmental compounds by AMS Measurements
O O Radiocarbon after four decades, an interdisciplinary perspective S S Analytical Chemistry 74
References
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References
S Radiocarbon 32 Journal of Chromatography A 827 Chemosphere 44 Chemosphere 47 O S Liebigs Annalen der Chemie 2 O Analytical Chemistry Kirk-Othmer Encyclopedia of Chemical Technology 1 S S S O S Environmental Toxicology and Chemistry 15 Method 552.2: Determination of haloacetic acids and dalapon in drinking water by liquid-liquid extraction, derivatization, and gas chromatography with electron capture detection S
References
S Journal of Chromatography A 671 S Fresenius Journal of Analytical Chemistry 361 Annales Botanici Fennici 30 S The Science of the Total Environment 160/161 O Screening Information Data Set for High Production Volume Chemicals 6 O Analytical Chemistry 59 O Analyst 115 A study of the presence of di- and trichloroacetic acid in European soils O O S O O Journal of Photochemistry and Photobiology A 112
References
O S S Environmental Science & Technology 38 S Environmental Science & Technology 30 Before civilization Phytotoxische Photooxidationsprodukte leichtflüchtiger organischer Verbindungen O Environmental Science & Technology 35 S S S O Methylocystis Bioanalysis and Biotransformation 17 S S S Journal of Chromatography A 859 S S Analytical Chemistry 72 S The Handbook of Environmental Chemistry 3 S
References
S Chemosphere 52 S S Haloacetic acids in the freshwater and marine environment S S S S S Journal of Chromatography A 718 S S S Analytica Chimica Acta 504 S S S S Journal of Experimental Botany 46 S S S S Annales Botanici Fennici 34 S Chemosphere 39 S Environmental Science & Technology 34
References
S Analyst 125 Radiocarbon after four decades, an interdisciplinary perspective S S Accelerator Mass Spectrometry S S S Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 172 Aufbau einer Hybridionenquelle und Entwicklung eines Gashandlingsystems zur Radiocarbondatierung von Mikrogrammproben Journal of Environmental Monitoring 2 O Water Research 37 Monitoring TCA in forest soils and deposition. Phase IIa/b - TCA mass balance study The pesticide manual
References
S Journal of American Water Works Association 90 Water Research 35 S Geophysical Research Letters 7
Appendix 1: Raw data from AMS measurement
Appendix 1: Raw data from AMS measurement V13/12 V13/12 V14/13 V14/13 C12[nA] C13[nA]
C14 [countingrates] O O O O O O O O O O O O O O O O O Targetname Run
Appendix 1: Raw data from AMS measurement V13/12 V13/12 V14/13 V14/13 C12[nA] C13[nA] C14 [countingrates] O O O O O O O O O O O O O Targetname Run
Appendix 1: Raw data from AMS measurement V13/12 V13/12 V14/13 V14/13 C12[nA] C13[nA]
C14 [countingrates] Targetname Run
Appendix 1: Raw data from AMS measurement V13/12 V13/12 V14/13 V14/13 C12[nA] C13[nA] C14 [countingrates] O O O O O O O O O O O O O O O O O O O O O Targetname Run
Appendix 1: Raw data from AMS measurement V13/12 V13/12 V14/13 V14/13 C12[nA] C13[nA]
C14 [countingrates] Targetname Run
Appendix 1: Raw data from AMS measurement V13/12 V13/12 V14/13 V14/13 C12[nA] C13[nA] C14 [countingrates] O O O O O O O Targetname Run
Appendix 1: Raw data from AMS measurement V13/12 V13/12 V14/13 V14/13 C12[nA] C13[nA]
C14 [countingrates] O O Targetname Run