organophosphate flame retardants (opfr) in municipal ... · potential risk to marine environment...

16th International EWA Symposium “Sustainable Wastewater Management – New solutions for new problems”

Munich, Germany, 8-9 May 2012

Prof. Dr.-Ing. Rita Hilliges

Wasserwirtschaft und Umwelttechnik

University of Applied Science

Hochschule Augsburg

NIVA – Norsk intitutt for vannforskning

Norwegian Institute for Water Research

Organophosphate flame retardants (OPFR)

in municipal wastewater treatment plants

http://www.niva.no/forsiden



Flame retarding mechanism of OPFRs

Skoog, 2010

Flame retardants: achieve flammability standard in

furniture, plastics, electronic equipment, textiles

Appr. 200 different types, classified after major constituents

Different mechanisms



History of flame retardants

Polychlorinated biphenyls (PCBs)

Banned late 1970ies

Toxic effects: endocrine disruption and neurotoxicity

Persistent: still found in sediment and aquatic foodweb!

1970

1980

1990

2000

2010



Histroy of flame retardents

Polychlorinated biphenyls (PCBs) 1970

1980

1990

2000

2010

Polybrominated diphenyl ethers (PBDEs)

hormone-disrupting effects, impaired neuro development

Persistent, bioaccumulative, toxic, highly lipophilic

long-range atmospheric transport ubiquitous

Banned 2004/2006: PentaBDE, OctaBDE

2008: DecaBDE

Mö

ller

et a

l., 2

01

2



Histroy of flame retardents

Polychlorinated biphenyls (PCBs) 1970

1980

1990

2000

2010

Polybrominated diphenyl ethers (PBDEs)

Organophosphate flame retardants (OPFRs)

High Production Volume chemicals HPVs

Consumption EU (2006): 91.000 to/a



Organophosphorus esters

TCEP

TCPP Known for 150 years as nerve gas and plant protective agent

Chlorinated OP: TCEP, TCPP, TDCP…

mainly used as flame retardant

Non-chlorinated OP: TBEP, TEHP, TnBP, TiBP…

mainly used as plasticizer, hydraulic fluids, flame retardant …

TCEP: carinogenic phased out, replaced by TCPP

TCPP and TDCPP: on 4th list of priority substances

EU commission

Suspected: neurotoxic and mutagenic potential

Suspected: persistent (at least chlorinated OP)



M

ölle

r e

t a

l., 2

01

2

OPFRs – Pacific and Indian Ocean air



OPFRs – Pacific and Indian Ocean air

global occurence:

marginal seas, open oceans and polar regions

concentrations up to 2 ng/m³

dominated by TCPP

and TCEP (carcirogenous)

1-3 magnitudes higher

than typical PBDE concentrations

heaviliy emitted into surface waters

Suspected sources: WWTPs



Screening of WWTPs in Norway

Eight municipal WWTPs

in south-east Norway

48.000 – 550.000 p.e.

Four WWTPs with chemical treatment only

Four WWTPs combined chem./bio. treatment

Six WWTPs discharge into marine water

OPFRs and other organic pollutants

Sludge samples

Flow proportional weekly composite samples



Sludge samples



Sludge samples Sludge samples (ng/g)

Median Min Max Other studies PNEC

TIBP 102 38.8 356 100a / 27-2,700b 640

TBP 94 26.4 304 39-850b 5,300

TCEP 128 30.4 276 70a / 6.6-110b 0.341 (wet weight)

TCPP 2,580 560 7,200 18,400a / 61-1,900b

1,300-2,200c 0.341 (wet weight)

DBPhP 3.9 0.8 20.8

DPhBP <LoD <LoD <LoD

TDCP 246 8.8 1040 90a / 3.0-260b 330

TBEP 3,660 236 23,600 <5.1-1,900b 810

TPhP 150 26.8 6,000 52-320b 95

EHDPP 2,300 21.2 12,800 320-4,600b

TEHP <LoD <LoD <LoD

ToCP 6 <LoD 20.8

TCP 460 10.8 12,000 8.9

LoD: Limit of Detection a) Bester, 2009 b) Marklund, 2005 c) Bester, 2005



Effluent samples



Effluent samples Effluent samples (ng/L)

Median Min Max Other studies

TIBP 168 104 308 29-2800c

TBP 41 <LoD 316 360-6,100a; 19-390c

TCEP 62 3.64 272 350-890a; 19-1800c

Mean: 350, Max: 410b

TCPP 600 14.4 1,160 Mean: 3,000, Max: 6,600b

1,500-24.000a

DBPhP 0.36 <LoD 4

DPhBP <LoD <LoD <LoD

TDCP 104 <LoD 276 130-450a; <8-820c

TBEP 158 <LoD 60,000 Mean: 440, Max: 790b

3,100-30,000a; 240-16,000c

TPhP 16.4 0.68 2,000 41-130a; 15-120c

EHDPP 7.6 1.04 48 9.2-69c

TEHP <LoD <LoD 5.6 <1.4a

ToCP <LoD <LoD 14.4

TCP 1.88 0.48 640

LoD: Limit of Detection a) Marklund, 2005 b) Bester, 2004



Effluent samples – risk assessment

PNEC PEC PEC/PNEC PEC PEC/PNEC

Marine ng/L effl., max ng/L Max effl., median ng/L median

TIBP 1,100 31 0.03 16.8 0.02

TBP 6,600 32 0.005 4.1 0.001

TCEP 6,500 (fresh water)

27 0.004 6.2 0.001

TCPP 640,000 (fresh water)

116 0.0002 60 0.0001

TDCP 1,300 28 0.02 10.4 0.008

TBEP 1,300 6,000 4.6 15.8 0.01

TPhP 16 200 12.5 16.4 1.03

TCP 3.2 64 20 0.19 0.06

Potential risk to the marine environment!

Calculated OPFR discharge WWPT H (550,000 p.e.): 100 kg/a



Fate of OPFRs in WWTPs

Mechanical treatment

Chemical treatment

Biological treatment

Removal rate % TBEP TiBP TBP TPhP TCEP TCPP TDCP

Mechanical 30 0 8 31 0 0 22

Mech.+Chemical 40 0 0 40 0 10 20

Mech.+Biological 50 90 60 60 0 0 10


Mechanical 30 0 8 31 0 0 22


Mechanical 30 0 8 31 0 0 22

Mech.+Chemical 40 0 0 40 0 10 20



Fate of OPFRs in WWTPs

Tunnel wash water experiements in Norway (Meland et al., 2011)

Sedimentation and filteration: peat filter / activated carbon filter

activated carbon: median elimination rate 84 %

Removal of chlorinated OPFRs > 70 %

Promising with regard to activated carbon filtration at WWTPs



Per capita esmissions PBDE

PBDE: brominated flame retardants (banned)

Per capita emissions between 0.01 and 1 µg/day/capita

Evenly distributed by population; independent from size / location



Per capita esmissions PFCs

PFCs: perflourinated compounds

High surface activity: hydrophobic and oil repelling

Stain resistant fabric protection, water proofing outdoor clothing,

non-stick products (e.g. Teflon)

Per capita emissions < 5 µg/day/capita

Evenly distributed by population; independent from size / location



Per capita esmissions OPFRs

Per capita emissions up to 245 µg/day/capita

Average ratio: 183

Large site-specific variations

Used in great variety of products

Traffic (road tunnels, airports) / handling of runoff important



Conclusions

OPFR “new flame retardants”

Concern about ecotoxicological potential

High volume chemicals ubiquitous (Arctic!)

1-2 magnitudes higher concentrations than PBDE

Screening Norway:

TCPP and TBEP dominating in sludge and effluent samples

WWTP effluent: 1 to 250 µg/day/capita

unevenly emitted by population

100 kgOPFRs/a emitted by Norway’s largest WWTP (550.000 p.e.)

Potential risk to marine environment (TBEP, TPhP, TCP)



Conclusions

Removal of OPFRs in WWTPs:

Very low removal rates for chlorinated OPFRs

Non-chlorinated OPFRs: removal mainly in aeration basins

No significant removal during mechanical treatment

Activated carbon filtration: successful with road runoff



Acknowledgements

Norwegian climate and pollution agency

Klif - Klima- og Forurensingsdirektoratet: for funding

Full title: “Occurrence of selected organic micropollutants and silver

at wastewater treatment plants in Norway” (report No. TA 2784)

NILU - Norwegian institute for air research: for analysis of samples

You: for your attention!



Prof. Dr.-Ing. Rita Hilliges

Wasserwirtschaft und Umwelttechnik

University of Applied Science

Hochschule Augsburg

NIVA – Norsk intitutt for vannforskning

Norwegian Institute for Water Research

Organophosphate flame retardants (OPFR)

in municipal wastewater treatment plants

http://www.niva.no/forsiden

organophosphate flame retardants (opfr) in municipal ... · potential risk to marine environment...

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