Bioaccumulation of PBDEs,

their replacement products

(TBB, TBPH, BTBPE) and

HBCD in freshwater mollusks

from the Yadkin River

(North Carolina, USA)

Mark J. La Guardia* and Robert C. Hale

Virginia Institute of Marine Science

College of William & Mary

Gloucester Point, Virginia

*markl@vims.edu

PBDEs, environment and human health

• Polybrominated diphenyl ethers (PBDEs)

• additive brominated flame-retardants (BFRs)

• formulations: Penta-, Octa-, Deca-BDEs

• uses: polyurethane foam, electronics (e.g. casings, wires) and textiles

• ubiquitous, persistent and bioaccumulative

• endocrine disrupters

• Penta- & Octa-BDEs

• 2004, production ended US, ban by EU

• 2009, listed POP Stockholm Convention

• Deca-BDE

• phased-out in Europe, 2008

• to be phased-out in US, 2013

BrBr

O

BrBr

O

Br

Br Br

Br

Br

Br

Br

Br Br

Br

Penta- and Octa-BDE replacement products

O

Br

Br

Br

O Br

Br

Br

BTBPE• TBB, TBPH and BTBPE

• additive brominated flame-retardants (BFRs)

• TBB, TBPH: detected in sewage sludge1, household dust2 and marine mammals3 (DNA damage exposed laboratory minnows4)

• BTBPE: detected in sewage sludge1, dust2, air5, sediment5, 6, aquatic species6 and bird eggs7

O

Br

Br

Br

Br

O

O

CH3

CH3

OCH3

CH3

Br

Br

Br

Br

O

O

CH3

CH3

TBB

TBPH

1La Guardia et al., ES&T 2010 2Stapleton et al., ES&T 2009 3Lam et al., ES&T 2009 4Bearr et al., Environ.. Tox. Chem 2010 5Hoh et al., ES&T 2005 6Wu et al., ES&T 2010 7Gauthier et al., ES&T 2009

• Penta- replacement

• Firemaster 550 and BZ-54 (Chemtura Corp. CT. USA)

• TBB (2-ethylhexyl 2,3,4,5-tetrabromobenozate)

• TBPH (di (2-ethylhexyl)-2,3,4,5-tetrabromophthalate)

• Octa- replacement

• FF-680 (Chemtura Corp. CT. USA)

• BTBPE (1,2-bis (2,4,6-tribromophenoxy) ethane)

• additive brominated flame-retardant (BFR)

• polystyrene foam, electronics, textiles

• 2001: 16,700 MT global demand

• Technical product: α-, β-HBCD (~20%), γ-HBCD (~80%)

• environmental exposure

• ubiquitous contaminant

• detected in sewage sludge1, house dust2, marine mammals3 and birds4,5

• human: breast milk6 and blood7

• considered an endocrine disruptor

• mimic thyroid hormone

• developmental neurotoxin8

• usage/review

• EU, phased-out by 2015

• US, EPA action plan 2010

• finalized by the end of 2011

-HBCD

-HBCD

-HBCD

Br

Br

Br

BrBr

Br

Br

Br

Br

BrBr

Br

Br

Br

Br

BrBr

Br

Hexabromocyclododecane (HBCD)

1La Guardia et al., ES&T 2010 2Stapleton et al., ES&T 2009 3Lam et al., ES&T 2009 4He et al., ES&T 20105Fernie et al., ES&T 2010 6Shi et al., ES&T 2009 7Meijer et al., ES&T 2008 8van der Ven et al., Tox Letters 2009

Yadkin River – outfall - samples

• Yadkin-Pee Dee River

• 690 km/430 miles, Blue Ridge Mountains North Carolina, South Carolina to the Atlantic Ocean

• Elkin, NC (textile outfall)

• 4MGD, wastewater treatment facility serves textile mills

• US EPA’s Toxics Release Inventory (TRI) 2001-2004 5350 kg/ 11,800 lbs deca-BDE released to surface water

• Sample Sites (collected 2009)

• sediments and mollusks

• 4-sites, Elkin (outfall) to Pilot Mountain State Park, NC

• 45 km/28 river miles

North Carolina

South Carolina

Atlantic Ocean

Boone, NC

Gastropod: Elimia proxima

Native range: North America (Virginia to Georgia)

Life span: several years

Feeding: grazer, algae (attached) and detritus

Reproduction: egg layers, mate yearly

Movement: <20m yr-1

Predators: fish, crayfish, birds…

Bivalve: Corbicula fluminea (Asian clam)

Native range: Asia and Africa

Nonindigenous specie: North and South America and Europe

Life span: 1-4 years

Feeding: filter-feeder, phytoplankton

Reproduction: hermaphrodite, several yearly broods

Movement: relatively sessile

Predators: fish, birds, raccoons…

Mollusk samples - bivalves and gastropods

Size Exclusion ChromatographyEnvirosep-ABC, 350 x 21.1 mm

(Phenomenex)

Enhanced Solvent ExtractionASE 200 (Dionex)

Solid Phase ExtractionGlass column, 2 gm silica

Freeze-dry

exchange to hexane

Fraction #13.5mL (hexane)

reduce volumeGC/ECNI-SIM MS

PBDEs, TBB, TBPH, BTBPE

Samples

(sediment and mollusks)

Fraction #26.5mL (hexane/DCM, 60:40)

Fraction #38mL (DCM)

Fraction #45mL (DCM/Ace, 50:50)

BFR extraction and analysis

Solvent exchange

UPLC/ESI-NI MS/MS (-, -, -HBCD)

0

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

4,500

Outfall 17Km (11miles) 25Km (16miles) 45Km (28miles)

Penta- & Octa- BDEs

Deca-BDEs

TBB, TBPH, BTBPE

α-, β-, γ-HBCD

BFRs – river sediments

River flow

Conc.

ng/g

(ppb)

dry

wt.

BFRs – sediment and mollusks (outfall)

(TOC or lipid normalized)

Penta- & Octa-BDEs

0

2,000

4,000

6,000

8,000

10,000

12,000

Co

nc.

ng

/g (

pp

b),

%T

OC

or

% l

ipid

BDE-47

BDE-100

BDE-99

BDE-85

BDE-154

BDE-153

BDE-183

Sediment Corbicula (clam) Elimia (snail)

Deca-BDEs

0

50,000

100,000

150,000

200,000

250,000

300,000

Co

nc.

ng

/g (

pp

b),

%T

OC

or

% l

ipid

BDE-209

BDE-206

BDE-208

BDE-207

Sediment Corbicula (clam) Elimia (snail)

TBB, TBPH & BTBPE

0

2,500

5,000

7,500

10,000

12,500

15,000

17,500

20,000

Co

nc.

ng

/g (

pp

b),

%T

OC

or

% l

ipid

TBB

TBPH

BTBPE

Sediment Corbicula (clam) Elimia (snail)

HBCD

0

50,000

100,000

150,000

200,000

250,000

300,000

350,000

Co

nc. n

g/g

(p

pb

), %

TO

C o

r %

lip

id

γ-HBCD

β-HBCD

α-HBCD

Sediment Corbicula (clam) Elimia (snail)

Penta- & Octa-BDEs

0%

20%

40%

60%

80%

100%

% C

on

trib

uti

on

BDE-183

BDE-153

BDE-154

BDE-85

BDE-99

BDE-100

BDE-47

Sediment Corbicula (clam) Elimia (snail)

BFRs – sediment and mollusks (outfall)

(TOC or lipid normalized)

Penta- & Octa-BDEs

0

2,000

4,000

6,000

8,000

10,000

12,000

Co

nc.

ng

/g (

pp

b),

%T

OC

or

% l

ipid

BDE-47

BDE-100

BDE-99

BDE-85

BDE-154

BDE-153

BDE-183

Sediment Corbicula (clam) Elimia (snail)

Deca-BDEs

0

50,000

100,000

150,000

200,000

250,000

300,000

Co

nc.

ng

/g (

pp

b),

%T

OC

or

% l

ipid

BDE-209

BDE-206

BDE-208

BDE-207

Sediment Corbicula (clam) Elimia (snail)

TBB, TBPH & BTBPE

0

2,500

5,000

7,500

10,000

12,500

15,000

17,500

20,000

Co

nc.

ng

/g (

pp

b),

%T

OC

or

% l

ipid

TBB

TBPH

BTBPE

Sediment Corbicula (clam) Elimia (snail)

HBCD

0

50,000

100,000

150,000

200,000

250,000

300,000

350,000

Co

nc. n

g/g

(p

pb

), %

TO

C o

r %

lip

id

γ-HBCD

β-HBCD

α-HBCD

Sediment Corbicula (clam) Elimia (snail)

Deca-BDEs

0%

20%

40%

60%

80%

100%

% C

on

trib

uti

on

BDE-207

BDE-208

BDE-206

BDE-209

Sediment Corbicula (clam) Elimia (snail)

BFRs – sediment and mollusks (outfall)

(TOC or lipid normalized)

Penta- & Octa-BDEs

0

2,000

4,000

6,000

8,000

10,000

12,000

Co

nc.

ng

/g (

pp

b),

%T

OC

or

% l

ipid

BDE-47

BDE-100

BDE-99

BDE-85

BDE-154

BDE-153

BDE-183

Sediment Corbicula (clam) Elimia (snail)

Deca-BDEs

0

50,000

100,000

150,000

200,000

250,000

300,000

Co

nc.

ng

/g (

pp

b),

%T

OC

or

% l

ipid

BDE-209

BDE-206

BDE-208

BDE-207

Sediment Corbicula (clam) Elimia (snail)

TBB, TBPH & BTBPE

0

2,500

5,000

7,500

10,000

12,500

15,000

17,500

20,000

Co

nc.

ng

/g (

pp

b),

%T

OC

or

% l

ipid

TBB

TBPH

BTBPE

Sediment Corbicula (clam) Elimia (snail)

HBCD

0

50,000

100,000

150,000

200,000

250,000

300,000

350,000

Co

nc. n

g/g

(p

pb

), %

TO

C o

r %

lip

id

γ-HBCD

β-HBCD

α-HBCD

Sediment Corbicula (clam) Elimia (snail)

TBB, TBPH & BTBPE

0%

20%

40%

60%

80%

100%

% C

on

trib

uti

on

BTBPE

TBPH

TBB

Sediment Corbicula (clam) Elimia (snail)

BFRs – sediment and mollusks (outfall)

(TOC or lipid normalized)

Penta- & Octa-BDEs

0

2,000

4,000

6,000

8,000

10,000

12,000

Co

nc.

ng

/g (

pp

b),

%T

OC

or

% l

ipid

BDE-47

BDE-100

BDE-99

BDE-85

BDE-154

BDE-153

BDE-183

Sediment Corbicula (clam) Elimia (snail)

Deca-BDEs

0

50,000

100,000

150,000

200,000

250,000

300,000

Co

nc.

ng

/g (

pp

b),

%T

OC

or

% l

ipid

BDE-209

BDE-206

BDE-208

BDE-207

Sediment Corbicula (clam) Elimia (snail)

TBB, TBPH & BTBPE

0

2,500

5,000

7,500

10,000

12,500

15,000

17,500

20,000

Co

nc.

ng

/g (

pp

b),

%T

OC

or

% l

ipid

TBB

TBPH

BTBPE

Sediment Corbicula (clam) Elimia (snail)

HBCD

0

50,000

100,000

150,000

200,000

250,000

300,000

350,000

Co

nc. n

g/g

(p

pb

), %

TO

C o

r %

lip

id

γ-HBCD

β-HBCD

α-HBCD

Sediment Corbicula (clam) Elimia (snail)

HBCD

0%

20%

40%

60%

80%

100%

% C

on

trib

uti

on

α-HBCD

β-HBCD

γ-HBCD

Sediment Corbicula (clam) Elimia (snail)

0.0

0.5

1.0

1.5

2.0

2 4 6 8 10 12

Biota Sediment Accumulation Factors (BSAFs)

(Cs/foc)

(Ct/fl)BSAF =

log Kow

(Bioaccumulation at BSAF >1, BSAF = lipid normalized tissue conc./organic carbon normalized sediment conc.)

0

1

2

3

4

5

6

7

5 6 7 8 9 10 11 12

log Kow

BS

AF

Corbicula (clam)

Elimia (snail)

BFRs BSAFs – Corbicula and Elimia

(Cs/foc)

(Ct/fl)BSAF =

BDE-154

octa-, nona-BDEs

BDE-47

α-, β-HBCD

γ-HBCD

BDE-100

BDE-209, TBB

BTBPE TBPH

BDE-99

BDE-153, -154

-HBCD

-HBCD

-HBCD

Br

Br

Br

BrBr

Br

Br

Br

Br

BrBr

Br

Br

Br

Br

BrBr

Br

0

0.5

1

1.5

2

2.5

3

3.5

BS

AF

α-HBCD, log Kow 5.07

β-HBCD, log Kow 5.12

γ-HBCD, log Kow 5.47

Bioaccumulation or bioisomerization*

(*Law et al., Environ. Tox. Chem. 2006)

Corbicula (clam) Elimia (snail)

• PBDEs, TBB, TBPH, BTBPE and HBCD

• enter the aquatic environment (via treated effluent)

• persistent, all detected 45Km (28 miles) downstream from outfall

• bioavailable, detected in Corbicula and Elimia

• BSAFs: TBB, TBPH and BTBPE (Penta- & Octa-replacement products)

• < Penta- & Octa-BDEs

• BDE-209 TBB, TBPH, BTBPE

• HBCD

• α-, β-HBCD BSAFs Penta-BDEs

• α-, β-HBCD BSAFs 3 to 6-times γ-HBCD

• indicates bioisomerization in low tropic organisms

• Transformation products

• methoxy and hydroxy-BDEs

• debrominate

• deca-BDE to more toxic lower brominated PBDEs

• TBB and TBPH

• TBPH to DEHP (di(2-ethylhexyl) phthalate)

• isomerization of γ-HBCD

Conclusions

OO

O

CH3

CH3

OCH3

CH3

DEHP

O

Br

Br

Br

Br

O

O

CH3

CH3

OCH3

CH3

TBPH