499>80 499>99

2.18

313>119 313>269

363>169 363>319

413>169 413>369

463>219 463>419

513>269 513>469

299>80 299>99

399>80 399>99

Transitions

1.28

1.63

1.91

Retention Time

2.15

2.36

1.02

1.70

Structure

PFOA

PFNA

PFDA

L-PFBS

L-PFHxS

L-PFOS

Perfluoro-n-nonanoic acid

Perfluoro-n-decanoic acid

K Perfluoro-n-butanesulfonate

Na Perfluoro-n-hexanesulfonate

Na Perfluoro-n-octanesulfonate

Abbreviation

PFHxA

PFHpA

Name

Perfluoro-n-hexanoic acid

Perfluoro-n-heptanoic acid

Perfluoro-n-octanoic acid

Rapid Quanti�cation of Per�uorinated Compounds in Drinking and Surface Water Using LC-MS/MS Jeremy Post, Christopher Gilles, William LippsShimadzu Scienti�c Instruments, Columbia, MD

For Research Use Only. Not for use in diagnostic procedures.

Creating an environment suitable for measuring PFCs required several adjustments to the stan-dard LCMS work�ow in both the way samples were prepared and data was acquired. Iterative modi�cations started with tubing replacements and LC hardware recon�guration, which was fol-lowed by using glass and metal only for sample preparation. Even a seemingly minor adjust-ment such as inverting the autosampler vial septa proved important to reducing the PFC chemi-cal background. Following these modi�cations the background reduced signi�cantly making possible the acquisition of calibration curves measuring down to 2.5 fg on column. The low stan-dard %RSD value for PFOA was 4.1 and for PFOS, 5.6. Seven of the eight compounds were de-tected in surface waters across central Maryland whereas four were found in drinking water, though in reduced amounts relative to surface water.

Though nearly ubiquitous, per�uorinated compounds can be e�ectively and quickly measured directly from surface and drinking water using a modi�ed con�guration of the LCMS-8050. This method can be used for routine monitoring of PFCs in water samples requiring only minimal sample preparation.

Per�uorinated compounds (PFCs) are synthetic molecules with carbon chains to which �uorine is bound by high strength carbon-�uorine covalent bonds. Useful due to their surfactant and hydro-phobic physicochemical properties these materials are used broadly since the 1950s in industrial applications such as the conveyance of stain and stick resistance to a wide variety of materials and products including clothing, cookware, carpet, and food containers. These molecules, now classi-�ed as persistent organic pollutants, are highly stable and resistant to biological degredation, therefore they persist in the environment, bioaccumulate, and due to their ready transport by water are found even in remote regions of Earth. As contaminants of emerging concern, research on PFCs is ongoing to determine the impacts of these materials on human health and the envi-ronment. A CDC study detected four of these analytes in >98% of serum samples representative of the general US population above age twelve. Low level analysis of these compounds is chal-lenging due to their ubiquitous presence in the laboratory and analytical instrumentation com-ponents.

PFOS25 fg

Figure 3: PFC calibration curves demonstrating excellent linearity at low analyte concentration matched with spectra showing the analyte LOQ and a chromatogram with 60 fg on column .

Novel Aspect

Introduction

Method Results

Discussion

Conclusions

Fast, low chemical background, high sensitivity measurement of per�uorinated com-pounds in water.

Surface water samples were collected and stored according to document SOP #EH-01 Sur-face Water Collection using the Direct Method. As the mobile phase transfer lines, degasser membrane, pump inlet block, and sample vial septa all utilize PTFE, made from a prominent PFC, per�uorooctanoic acid (PFOA), these components were either exchanged or bypassed to eliminate all sources of extraneous analyte from the instrumentation. The calibration curve solutions were prepared in glass vials using glass syringes with a metal plunger. PFC standards were purchased from Wellington Laboratories. A Shimadzu LCMS-8050 was used for analyte separation and mass spectrometry. Analytes were ionized using negative mode electrospray ionization. All samples were passed through 0.2 um glass �ber �lter prior to analysis. The method required only 3.15 minutes. Table 1 provides optimized transitions and retention times for the PFCs measured in this method. Chromatography Parameters

Flow Rate: 0.35 mL/min Mobile Phase A: 10 mM ammonium acetate in waterColumn oven: 35°C Mobile Phase B: 10 mM ammonium acetate in 80:20 MeOH:ACNInjection volume: 20 μL Column: Supelco Titan C18 (50 x 2.1mm 1.9 um) Gradient: Linear 45% - 97% B 0-2.6 minutes

Mass Spectrometry Parameters

Nebulizing Gas 2.2 L/min Interface Temperature 230 CHeating Gas 8 L/min Desolvation Line Temperature 95 CDrying Gas 10 L/min Heat Block Temperature 225 C Column Oven 35 C

Liberty Reservoir

Centennial Lake

Little Patuxent River

Middle Patuxent River

Figure 1: Central Maryland surface water source locations

Figure 2: Direct method surface water sampling collection technique.

Table 1: Method information for the perfluorinated compounds measured in surface and drinkingwater

0.0 25.0 50.0 75.0 100.0 125.0 Conc.0

250000

500000

750000

1000000

1250000

Area

0.0 25.0 50.0 75.0 100.0 125.0 Conc.0

250000

500000

750000

1000000

1250000

1500000

Area

0.0 25.0 50.0 75.0 100.0 125.0 Conc.0

250000

500000

750000

1000000

1250000

1500000

Area

0.0 25.0 50.0 75.0 100.0 125.0 Conc.0

250000

500000

750000

1000000

1250000Area

0.0 25.0 50.0 75.0Conc.0

100000

200000

300000

400000

500000

600000

700000

Area

0.0 25.0 50.0 75.0 100.0 125.0 Conc.0

50000

100000

150000

200000

250000

300000

Area

0.0 25.0 50.0 75.0 100.0 125.0 Conc.0

25000

50000

75000

100000

125000

150000

175000

200000

225000

250000Area

0.0 25.0 50.0 75.0 100.0 125.0 Conc.0

25000

50000

75000

100000

125000

150000

175000

Area

PFNA5-3200 fg

PFOA25-3200 fg

PFHpA5-3200 fg

PFHxA2.5-3200 fg

PFDA25-1600 fg

L-PFBS2.5-3200 fg

L-PFHxS5-3200 fg

PFOS25-3200 fg

R2 = 0.999 R2 = 0.998 R2 = 0.998 R2 = 0.996

R2 = 0.997 R2 = 0.998 R2 = 0.999 R2 = 0.991

1.15 1.20 1.25 1.30 1.35 1.40

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

5500

6000313.00>119.10(-)313.00>268.90(-)

1.50 1.55 1.60 1.65 1.70 1.75

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

5500

363.00>169.10(-)363.00>319.10(-)

1.85 1.90 1.95 2.00 2.05

0

2500

5000

7500

10000

12500

15000

17500

20000

22500

25000

27500

30000

413.00>169.00(-)413.00>369.00(-)

2.10 2.15 2.20 2.25

0

2500

5000

7500

10000

12500

15000 463.00>219.00(-)463.00>419.00(-)

2.30 2.35 2.40 2.45 2.50 2.55

0

2500

5000

7500

10000

12500

15000

17500

20000

22500

25000

27500 513.00>269.00(-)513.00>469.00(-)

0.90 0.95 1.00 1.05 1.10

0

50

100

150

200

250

300

350298.90>98.90(-)298.90>79.80(-)

1.60 1.65 1.70 1.75 1.80

0

50

100

150

200

250

300

350

400

450

500

550

600

650

399.00>98.90(-)399.00>79.80(-)

2.10 2.15 2.20 2.25

0

250

500

750

1000

1250

1500

1750

2000

2250

2500

2750

3000

499.00>98.95(-)499.00>79.95(-)

PFNA5 fg

L-PFHxS5 fg

PFOA25 fg

PFHpA5 fg

L-PFBS2.5 fg

PFDA25 fg

PFHxA2.5 fg

0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.3 2.4 2.5 min

0

5000

10000

15000

20000

25000

30000

35000

40000

45000

50000

PFHx

A

PFDA

PFHp

A

L-PF

BS

PFOA

L-PF

HxS

PFOS

PFNA

Per�uorinated compounds60 fg on column

0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.3 2.4 2.5 min

0

25000

50000

75000

100000

125000

150000

0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.3 2.4 2.5 min

0

10000

20000

30000

40000

50000

60000

70000

80000

90000

100000

110000

120000

0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.3 2.4 2.5 min

0

10000

20000

30000

40000

50000

60000

70000

0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.3 2.4 2.5 min

0

10000

20000

30000

40000

50000

60000

70000

80000

90000

100000

110000

120000

130000

140000

0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.3 2.4 2.5 min

0

25000

50000

75000

100000

125000

150000

175000

0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.3 2.4 2.5 min

0

25000

50000

75000

100000

125000

150000

175000

Lab Blank

Centennial Lake

Liberty Lake

Little Patuxent River

Middle Patuxent River

Drinking (Tap) Water

PFHxA 0.34 1.19 0.59 0.68 1.17 0.51PFHpA 0.1 0.36 0.33 0.33 0.33 0.16PFOA 0.79 1.09 0.92 1.04 1.05 0.37PFNA 0.22 0.24 0.24 0.25 0.26 0PFDA 0.71 0.43 0.16 0.07 0.08 0L-PFBS 0 0 0 0 0 0L-PFHxS 0 0 0 0.06 0.06 0.05PFOS 0 0 0.13 0.19 0.1 0

Middle Patuxent

River

Drinking Water

Lab BlankCentennial

LakeLiberty

Lake

Little Patuxent

River

Table 2 : Calculated amounts of PFC materials in the surface and drinking water samples. The measured amounts were averaged (n=4) and re-duced by the amount of each analyte detected in the Lab Blank (18MOhm purified water). These values were then divided by the injection volume to determine the final concentration in ng/L.

Figure 4: Representative PFC LC Chromatograms from 20uL injections of surface and drinking water.