Measuring PCBs in Lake Ontario Surface Water Using

Full-Scan Congener Methods

Frederick Luckey

U.S. Environmental Protection Agency, Region 2

Simon Litten

New York State Dept. of Environmental Conservation

Brian Fowler

AXYS Analytical Services (Currently with Waters)

Implications for designing environmental assessment programs

Objectives

• Support the information needs of the Lake Ontario

Lakewide Management Plan by measuring surface water

concentrations of:

PCBs

Pesticides

Dioxins / Furans

Mercury

PBDEs

• Identify contaminants exceeding water quality criteria.

Mono- chlorinated biphenyl 1 Chlorine

Di - chlorinated biphenyl 2 Chlorines

Tri- chlorinated biphenyl 3 Chlorines

Tetra - chlorinated biphenyl 4 Chlorines

Penta - chlorinated biphenyl 5 Chlorines

Hexa- chlorinated biphenyl 6 Chlorines

Hepta- chlorinated biphenyl 7 Chlorines

Octa- chlorinated biphenyl 8 Chlorines

Nona- chlorinated biphenyl 9 Chlorines

Deca - chlorinated biphenyl 10 Chlorines

Polychlorinated Biphenyl (PCB) Terminology

Congener – One of 209 possible configurations of the

number and position of chlorines on the two phenyl rings.

Homolog – Set of congeners having the same number of

chlorines / molecular weight.

10 PCB

Homolog

Groups

PCB Homolog Group

01020304050

mon

o di tri

tetra

penta

hexa

hepta

octa

nona

deca

Commercial PCB Formulation: Aroclor 1248

Us=

Polychlorinated Biphenyl (PCB) Terminology

Using Homologs to Simplify Data Analysis

%

Total

PCB

2’ 3’

5’

2

4

3

6 6’

4’

5

2,2’,4,4’- tetrachlorobiphenyl

IUPAC # PCB- 47

Polychlorinated Biphenyl (PCB) Terminology

Great Lakes Basin

• Spatially, temporally integrated

large volume water samples

• 24 hour continuous sampling

• Sampled from ~1 m depth

Lake Ontario Open Water Sampling

• Sampling in water depths >75 m

Fall 1999

Research Vessel Lake Guardian

EPA Great Lakes National Program

Office

Lake Ontario Surface Water Large Volume Sampling

Western / Central / Eastern Basin Sampling Grids

Province of Ontario

New York State

Nytex Netting

XAD Resin #1

Glass Fiber

Cartridge Filter

Surface Water Intake

1 um

Total Organics Platform Sampler (TOPS)

XAD Resin #2

~I m deep

filter out large

zooplankton

& debris

capture solids

capture dissolved

Lake

Large Volume Sampler

capture any break thru

Lake Ontario Surface Water Large Volume Sampling

• XAD Resin Columns 35 grams each

flow rate 300 – 600 ml / min

sample volumes ~800 L

• Glass Fiber Cartridge Filters 2.5” diameter x 4”

flow rate 3 L / min

1 micron nominal pore size

sample volumes ~5000 L

Dissolved Phase

Solids Phase

Calculating PCB Water Concentrations

PCB mass (picograms)

TOPS Sample Volume (L)

= Water Conc. (pg/L)

is inversely proportional to Sample

Specific

Detection

Limit

Sample

Volume

PCB Analytical Method

EPA Method 1668A

• High resolution gas chromatography & mass spectrometry

• Solvent extracted & cleaned with liquid chromatography

• Samples spiked with 13C12-labelled PCB congeners

• Selected ion method

• EI mode at 10,000 resolution

• Identifies 160 congeners / coeluting congener groups

Data Handling

• Lab results corrected based on 19 13C12-labelled PCB

congener surrogate recoveries

• Values <3X Lab or Field Blank Reject.

• Values >3X and <5X Lab or Field Blank Flag

• Non-detects = Zero

Data Handling

Lake Ontario Surface Water PCBs (pg/l)

Picograms/ Liter

(parts per quadrillion)

New York Water Quality Criteria

0 10 20 30 40 50

Central

Eastern

Western-1

Western-2

Solids

Dissolved

Can You Believe These Numbers?

Importance of Quality Control

Field Sampling QA Checks

• XAD capture efficiency

• Suspended Solids capture efficiency

• Check on XAD “wash-out” effect - 13C12 PCB surrogates

• Duplicate Samples & Field Blanks

• Manual Check on Flow Meter Accuracy

Lab QA Checks

• Samples spiked with internal 13C12 PCB surrogates

• Lab Blanks

XAD Resin – Use of “Washout” Field Surrogates

13C12-Labelled PCB-31, PCB-95 PCB-153

Picogram / sample

13C12-labelled PCB-153

0

50000

100000

150000

Lab

Blank

Field

Blank

XAD #1 XAD #2 XAD #3 XAD #4 XAD #5

Spike Conc.

Measured Conc.

Lake Ontario Surface Water PCBs – Raw pg/sample

Field & Lab Blank Issues

Picogram / sample

0 10000 20000 30000 40000

Blank

Blank

Blank

Filter

XAD

Filter

Filter

Filter

Filter

XAD

XAD

XAD

XAD

Field Sample

Lab Blank

Field Blanks

Lake Ontario Surface Water PCBs

XAD Resin Field Blank Issues

Picogram / sample

0 2000 4000 6000 8000 10000 12000

Sample - 1

Sample - 2

Sample - 3

Sample - 4

Sample - 5

Field Blank

BZ-44

BZ-45

BZ-68

XAD Column #1

Checking XAD Field Extraction Efficiency

XAD Column #2

( Divinylbenzene-styrene copolymer resin )

• Ideally all contaminants will be captured on 1st XAD column

XAD Resin Capture Efficiency

Percent of Congeners Captured on First XAD Column

• 100% of congener mass captured on the first column

Except for:

% Captured on 1st XAD Column

PCB

Congener

IUPAC ID

0 20 40 60 80 100

3

16

22

26 + 29

37

42

48

60

84

105

135 + 151 + 154

187

Duplicate Results

Comparison of PCB Homolog Total Concentrations

Pg / l

Pg / l

Dissolved Phase

XAD Resin

Solids Phase

Glass Fiber

Cartridge Filter

PCB Homolog Group

0

2

4

6

8

10

12

14

Mono Di Tri Tetra Penta Hexa Hepta Octa Nona Deca

West #1

West #2

0

2

4

6

8

10

12

14

Mono Di Tri Tetra Penta Hexa Hepta Octa Nona Deca

West #1

West #2

Lake Ontario Total PCBs

Homolog Percent Relative Abundance

%

Total

PCB

PCB Homolog Group

0

10

20

30

Mono Di Tri Tetra Penta Hexa Hepta Octa Nona

Central

Eastern

Western #1

Western #2

PCB Homolog Patterns in Field Blanks

%

Total

PCB

PCB Homolog Group

0

20

40

60

80

100

Mono Di Tri Tetra Penta Hexa Hepta Octa Nona Deca

Filter

XAD

Lake Ontario Surface Water PCBs

Suspended Solids

%

Total

PCB

PCB Homolog Group

0

10

20

30

Mono Di Tri Tetra Penta Hexa Hepta Octa Nona Deca

Central

Eastern

Western #1

Western #2

Average Lake Ontario Surface Water Total PCBs

Congeners > 1% of Total PCBs

PCB

Congener

IUPAC ID

0 2 4 6 8

147 + 149

3

56

129 + 138 + 160 + 163

153 + 168

83 + 99

118

37

86 + 87 + 97 + 119 + 125

64

26 + 29

49 + 69

40 + 41 + 71

66

22

1

110 + 115

90 + 101 + 113

15

21+ 33

16

93 + 95 + 98 + 100 + 102

17

4

61 + 70 + 74 + 76

8

18 + 30

52

31

20 + 28

11

% of Total PCB

Lake Ontario Surface Water Total PCBs Fall 1999

Relative Abundance of Dominant PCB Congeners

% of Total PCBs

Di

Tetra

Tri

Penta

0 2 4 6

4

8

11

18 + 30

20 + 28

31

52

61 + 70 + 74 + 76

93 + 95 + 98 + 100 + 102Eastern

Central

West #1

West #2

1242 1016 1248

4 4 4.5

8 9 10

11 0 0

18 + 30 9 11 10

20 + 28 3.6 4

31 4.5 4.7 9.3

52 4 4.3 8.3

61 + 70 + 74 + 76 5.6 3.75 6.64

93 + 95 + 98 + 100 + 102 0.66 0.22

% of PCB Aroclor Mixture

Dominant Lake Ontario PCB Congeners and Commercial PCB Formulations

PCB

Congener

IUPAC ID

Important Great Lakes Monitoring Programs

Understanding Contaminant Sources & Loadings

Niagara River Upstream-

Downstream Monitoring Program

International Atmospheric

Deposition Network

(IADN)

Sources of Lake Ontario

PCB Loadings (Kg/Year)

-400 -300 -200 -100 0 100 200

St. Lawrence R. Outflows

Atmospheric Volatiliz.

Atmospheric Deposition

Point Sources

Lake Ontario Basin Tribs.

Niagara R. Basin

Other Great Lakes

Kilograms Per Year

Net Change -283 Kg/Year

0 2 4 6 8

147 + 149

3

56

129 + 138 + 160 + 163

153 + 168

83 + 99

118

37

86 + 87 + 97 + 119 + 125

64

26 + 29

49 + 69

40 + 41 + 71

66

22

1

110 + 115

90 + 101 + 113

15

21+ 33

16

93 + 95 + 98 + 100 + 102

17

4

61 + 70 + 74 + 76

8

18 + 30

52

31

20 + 28

11

PCB Congeners Not Included in IADN & US/DS

PCB

Congener

IUPAC ID

PCB-11

IADN & US/DS

PCB-1

IADN

PCB-37

US/DS

% of Lake Ontario Surface Water PCBs

PCB-11 as % Total PCB

PCB-11 in Selected Surface Waters

0 2 4 6 8 10 12

Hudson River

Upstrm

Hudson River

Dwnstrm

Newark Bay

Lake Ontario

Long Island

Sound

Known Sources of PCB-11

Diarylide Yellow Pigment Manufacturing

• Associated with 3,3’-dichlorobenzidine salts

• Intermediates in the manufacture of diarylide yellow

• Loss of distal ammonia groups produces PCB-11

Designing Environmental Assessments

Selecting a PCB Analytical Method

• Financial resources

• Available Analytical equipment / labs / staff

• Regulatory data requirements

• Historical data sets

• Expected levels of contamination / interferences

• Detection limit requirements

Factors to Consider:

• Use full-scan congener methods on some samples to ensure

that all environmentally significant congeners are recognized.

• Ensure that detection limits are low enough to determine if

water quality criteria are being met.

• Evaluate full-scan results to determine if selected analytical

approach will adequately characterize target area.

Recommendations for Designing PCB Surface Water

Environmental Assessment Monitoring Strategies

Lake Ontario Surface Water PCBs Fall

1999

• Total PCBs are ~ 40 pg/L in open waters

• Tri- & Tetrachlorobiphenyls dominant homologs

• > 90% of PCBs in dissolved phase

• Similar congener & homolog patterns across lake

• Dominant congener, PCB-11, not included in routine

monitoring, unrelated to commercial PCB mixtures

Acknowledgemen

ts

Thanks for the support provided by:

USEPA Great Lakes National Program Office

Captain & Crew of the R/V Lake Guardian