PBDEs: Will Our Sludge Burn

Karin Didriksen North

City of Palo Alto

650-494-7629

Karin.North@cityofpaloalto.org

Polybrominated Diphenyl Ethers

• What are PBDEs?

• Why are we concerned?

• Palo Alto’s sampling results

Polybrominated Diphenyl Ethers

• 209 congeners• 1 to 10 bromines• Mono smallest congener• Deca largest congener• Similar to PCBs and

Dioxins in regards to number of congeners

Background

• Added to many consumer products

• Chemical fire retardant

• Saves lives

• On the Regional Board’s “watch list”

Commercial Uses

High-impact plastic; other plastics, rubbers

and resins 1 to 10 % by weight of TV and computer

casings Polyurethane foam (30% by weight)

(furniture) Textile coatings (drapes, carpet backings)

Plastic materials that contain PBDEs– ABS– polyacrylonitrile (PAN)– polyamide (PA) – polybutylene terephthalate

(PBT)– polyethylene (PE)– polyvinyl chloride (PVC) – polyurethane (PUR) (foam)– unsaturated polyester

(UPE).

– cross-linked polyethylene (XPE)

– polyethylene terephthalate (PET)

– polypropylene (PP)– polystyrene (PS) – high-impact

polystyrene (HIPS)

Commercial Mixtures of PBDEs

• Penta-BDE (used in foam)

– Polyurethane foam in seat

cushions and carpet padding

– Printed circuit boards

– All congeners highly

bioaccumulative

– 86 to 99% of congeners

found in human tissues

Commercial Mixtures of PBDEs (cont)

• Octa-BDE (used in plastics, textiles)

– Electrical connectors

– Automotive interior parts

• Deca-BDE (plastics, textiles)

– Computer cases

– Carpet backing and textiles

PBDE Use in the Americas

PBDE Technical Mixture

Million lbs/yr (2001)

% of World’s

UseProduct Uses

Penta-BDE†

15.7 95 Furniture (foam cushions)

Octa-BDE 3.3 40 Electronics (ABS plastic, cable)

Deca-BDE 54.0 44 Electronics (HIPS plastic) and textiles

† Highly bioaccumulative BSEF, 2003

Environmental Concerns• Endocrine Disruption

• Persistent Organic Pollutants (POP)/ Persistent Bioaccumulative Toxicants (PBT)– Structurally similar to PCBs and DDT

– Lower brominated congeners bioaccumulate

• Emerging Environmental Challenge

• High Production Volume (HPV) Chemical

Structural Similarity of PBDEs, Their Metabolites and Environmental Derivatives

to T4 and PCBs

O

O

I

I

I

I

OH

NH2

OH

Br

Br Br

Br Br

O

Thyroxine (T4)

2,2',4,4',6-pentabromodiphenylether (PBDE-100)

4-(2',4',6'-tribromophenoxy)-2,6-dibromophenol (hydroxy-PBDE)

2-(2',4'-dibromophenoxy)-4,6-dibromoanisol (methoxy-PBDE)

CH3

BrO

O

Br Br Br

Br

Br

O

Br

Br

Br

OH

Cl

Cl

Cl

Cl

Cl

Cl

2,2',4,4',5,5'-hexachlorobiphenyl (PCB-153)

Br

O

Br

BrBr

Br

2,3,4,7,8-pentabromodibenzofuran (PBDF)

PBDE concentrations on the rise… Organohalogen Compounds in Human Milk in Sweden

(Norén and Mieronyté, 1998)

C o m p a r i s o n B e t w e e n C o n c e n t r a t i o n s o f P B D E s i n B r e a s t M i l k f r o m N o r t h A m e r i c a a n d E u r o p e

S a m p l i n g Y e a r

1 9 7 5 1 9 8 0 1 9 8 5 1 9 9 0 1 9 9 5 2 0 0 0

Co

ncn

etra

tio

n (n

g/g

lip

id w

eig

ht)

0

5 0

1 0 0

1 5 0

2 0 0N o r t h A m e r i c aS w e d e nF i n l a n d

S a m p l e s c o l l e c t e d i n A u s t i n & D e n v e r

S a m p l e s c o l l e c t e d i n N e w Y o r k S t a t e

C a n a d i a n M i l k B a n k

C a n a d i a n M i l k B a n k

4

C a n a d i a n M i l k B a n k a n d N e w Y o r k S t a t e f r o m R y a n a n d P a t r y 2 0 0 0 , D e n v e r a n d A u s t i n r e s u l t s f r o m P a p k e e t a l

2 0 0 1 ; S w e d i s h d a t a f r o m M e i r o n y t e G u v e r n i u s a n d N o r e n 2 0 0 1 , F i n n i s h d a t a f r o m S t r a n d m a n e t a l . 2 0 0 0

Figure courtesy of Dr. John Ryan of Health Canada and Dr. Mehran Alaee of Environment Canada:

Time-trend: PBDEs in Blubber of California Seals

0100020003000400050006000700080009000

01/01

/89

01/01

/91

12/31

/92

12/31

/94

12/30

/96

12/30

/98

PB

DE

(ng

/g li

pid)

N=11 (She et al., 2002)

PBDEs in Columbia River Whitefish

0

10

20

30

40

50

60

70

80

1992 1995 2000

Sum PBDE (ng/gfresh weight)

From Genelle, British Columbia

Rayne et al. (2003) Environ Sci Technol 37(13):2847-54.

PBDEs Have Become Ubiquitous Environment Contaminants

PBDEs are measured in – Indoor and outdoor air– Remote Arctic regions (i.e., long-range transport)– House and office dust– Rivers and lakes and sediments– Sewage sludge– Foods– Biota (terrestrial and marine mammals, fish,

humans)

PBDE Life CyclePenta-BDE Deca-BDE

Consumer productsPolybrominated Dioxins and Furans

Air/ Dust Waste

Food (penta)

(Urban runoff; Sewage sludge;E-waste)

Biota (fish)

Hydroxy-PBDEsMethoxy-PBDEs

Cross- media issue

(Indoor/ outdoor)

Palo Alto’s Study

• August 2002

• 3 days of sampling, composite samples

• Effluent and biosolids tested for 41 PBDE congeners

• Incinerator emissions tested for brominated furans and brominated dioxins

• Concentration levels at ppt (ng/L or ng/kg)

Palo Alto’s Loading Data

• 96% of PBDEs sorb onto biosolids

• 4% of PBDEs are discharged to Bay

• Incinerator transforms PBDEs to brominated

furans and brominated dioxins

• Air pollution control device destroys 99.9%

of dioxins and furans

Fate of PBDEs(wastewater treatment plant)

Influent (~ 50 lbs/year)

Stack emissions (PBDF /PBDD) <6.1 x 10-7 lbs/yr

Effluent 2 lbs/yr

Sludge 48 lbs/yr

Incinerator

Ash(not analyzed)

Penta Formulation

Accounts for >90 % of the PBDEs in most humans. However, minor congeners may be important.

Br

Br Br

Br Br

O

2,2',4,4',6-pentaBDE (PBDE-100)

2,2',4,4'-tetraBDE (PBDE-47)

2,2',4,4',5-pentaBDE (PBDE-99)

2,2',4,4',5',5-hexaBDE (PBDE-153)

2,2',4,4',5,6'-hexaBDE (PBDE-154)

Br Br

Br Br

Br Br

O

Br

Br Br

Br Br

O

Br

Br

Br Br

Br Br

O

Br

Br Br

Br

O

Mass of PBDEs in Effluent and Biosolids

11

13

2

1 1

17

0.73 0.780.14 0.07 0.05 0.12

02468

1012141618

BDE-47 BDE-99 BDE-100

BDE-153

BDE-154

BDE-209

lbs/

year

Biosolid Effluent

Penta-Formulation Deca-BDE

Comparison of Sludge Results (ug/kg dry weight)

SourcePenta

Formulation*Deca- BDE

City of Palo Alto 1,918-2,086 1,010-1,440

Hale’s study (Throughout U.S.)

1,100-2,290 85-4,890

European Studies 0.4-239 140-350

*sum of “penta-like” congeners

Correlation of PBDF with PBDE in German Sewage Sludge Used on Crops

• .

Hagenmaier et al. (1992) Chemosphere 25:1457-62

PBDE levels in U.S. sludge are 10- to 100-fold higher than European samples (Hale et al., 2001 Nature 412:140-1).

Overview of Results

• PBDE concentration in US Sludge is 10 to 100x greater than Europe

• Deca-BDE largest concentration in biosolids (~1,183 ppb)– Renewed concern over Deca (new data on

debromination by UV and biota)

• BDE-99 (part of penta-formulation) largest concentration in effluent (~0.01 ppb)

Potential Sources to POTW

• Unclear direct source since it is found

everywhere in the environment

• Some possible sources include:

– Rinsing of cleaning rags

– Carpet cleaning

– Laundry and shower gray water

– Human waste

Penta and Octa-BDE are now Banned

• Banned in California starting 2008

– AB302 (Chan et al.) signed into law August, 2002

• US manufacturer announced it will

voluntarily cease production by end of 2004

• Banned in European Union starting 2005

• Already voluntarily phased out in Japan

Text of California Ban (AB302)

“ On and after January 1, 2008, a person may

not manufacture, process, or distribute in

commerce a product, or a flame-retarded part

of a product, containing more than one-tenth

of 1 percent of pentaBDE or octaBDE, by

mass.”

Summary• 96% of PBDEs that enter the plant end up in

the sludge

• High concentration of PBDEs in sewage sludge

• US PBDE sludge concentrations 10 to 100x

greater than Europe

• Unclear if 2 lbs/year is a significant

contribution to the Bay

General Summary

• PBDEs in consumer products are escaping

into the environment – now everywhere

• PBDE levels rising rapidly in fish, other

wildlife and people in North America

• Penta- and Octa-PBDE banned in CA and

the EU; not used in Japan.

Key Sources for PBDEs

• “Tracking the Fate of Polybrominated Diphenyl

Ethers (PBDEs) at the Regional Water Quality

Control Plant, Palo Alto, Ca http://www.city.palo-

alto.ca.us/cleanbay/pdf/PBDE04.pdf

• Brominated Flame Retardants Information

Clearinghouse funded by CalEPA

http://www.greenstart.org/efc9/