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Assessing effects of metals to freshwater and marine systemsKatrien Delbeke

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Setting environmental quality standards … the Water Framework Directive ….

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EU Water Framework DirectivePrinciples for compliance checking

CHEMICAL STATUS

Annex X + 8 other pollutants (EQS)

Pass

Background

Fail

Biological quality

Physico-chemical quality

Annex VIII pollutants (EQS)

Pass/fail

High

Good

Mod

Poor

Bad

Ecology

Chemical

Lowest

ECOLOGICAL STATUS

Lowest

Pass/fail

Lowest

CLASSIFICATION

EC EQS guidance

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Environmental compartmentWater Sediment Biota

Receptor(s) at risk

Humans X (consumption of

fish products)

Benthic biota X X

Pelagic biota X (secondary poisoning)

Top predators

(birds, mammals)

X (secondary poisoning)

Setting environmental quality standards (EC EQS guidance and Norway EQS proposal)

EC EQS guidance

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EU Water Framework Directive Setting environmental quality standards (EQS)

Some important documents

- Common Implementation Strategy for the Water Framework Directive

(2000/60/EC) - Guidance Document No. 27: Technical Guidance For

Deriving Environmental Quality Standards Technical Report - 2011 –

055 …..= EC EQS guidance

- Draft Norwegian background document on environmental quality

standards (Feb 2013) ….= Norway EQS proposal

- Questions/Comments submitted by industry on the Norwegian

…= industry comments

- REACH dossiers submitted to ECHA

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Metal- specific characteristics- Metals are naturally occurring … varying background

- Some metals are essential

… Organisms have adapted mechanisms to cope against variability in

metal concentrations (regulated uptake/elimination; internal binding)

… Bioconcentration factors are NOT constant but depending on

background values = Biota standard NOT relevant for Cu/Zn

- Metals/metal compounds toxicity driven by Me-ions.

… NOT Total or dissolved metals BUT Bio-availability of metal ions

… Metal ions need to be released from sparingly soluble metal

materials (eg ore bodies, slags, tailing) to be bio-available

Setting environmental quality standards

(EC EQS guidance and industry comments to Norway EQS proposal

EC EQS guidance

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Metal Freshwater AA EQS (µg/l)

remarks

Hg and its compounds 0.05 Consider also biota

Cd and its compounds ≤ 0.08 If hardness < 40mg CaCO3/l

0.08 H: 40 - ≤ 50

0.09 H: 50 - ≤ 100

0.15 H: 100 - ≤ 200

0.25 H: ≥ 200

0.20 generic

Pb and its compounds 1.2 bio-available directive 2013/39/EU

Ni and its compounds 4 bio-available directive 2013/39/EU

Environmental quality standards for EU priority substances

(EC EQS guidance -12 August 2013)

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Norway EQS setting – background document …industry assessment…

Risk assessment data used

Statistical evaluation for data-rich assessments used

Missing : metal-specific aspects of the EC EQS guidanceo Incorporation of bio-availability into the compliance settingo Incorporating background levels into the compliance setting

Missing : Reach updates o Copper and zinc marine mesocosm study = now from REACH

Uncertainty around Sediment EQSo Freshwater versus marine partitioning coefficient (Kd) values…?

How the different classes were assigned….

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Setting a Freshwater EQS

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Setting environmental quality standards (Metal- specific EC EQS guidance)

Bio-availability models available?(BLM, regression, speciation)

Evaluate/compile ecotox data. If possible, express data on dissolved basis (water) or dry weight basis (sediment)

Is between-species extrapolation possible?

STEP 2 - full bioavailability correctionQS reference

STEP 2- baseline bioavailability correction

QS genericBio-availability correction – option 2 – BioF approach

Is the QS reference < background level?

Keep TRA - no background correction QS generic or QS reference, TRA

STEP 3 - use ARA – Background correctionQS generic or QS reference, ARA

Keep QS generic

No bio-availability correction – option 1

no

yes

yesno

yesno

STEP 1 : Generate a QS generic

Bio-availability correction – option 2 or 3

Step 1 : Generic EQS

Step 2: Bio-availability

Step 3 : Background

Norway- EQS application

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Importance of bioavailability - freshwater

Factor 30 difference EC50 D. magna

same species, same strain, different waters

0

100

200

300

400

01 02 03 05 06 07 07 08 09 10 11

48

h-E

C5

0 in

µg

Cu/

L

648

Evidence on site-specific toxicity for Cd, Ni, Pb, Cu, Zn, ….related to DOC, pH, Ca, Na, ….

Can we quantify the bio-availability effect?

0

100

200

300

400

500

600

1 2 3 4 5 6 7 8

Location

NO

EC

(µg

Zn/L

)

Bioavailability – freshwater

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Predict Metal bio-availability - freshwaterThe BIOTIC LIGAND MODEL for fish & invertebrates

Cu2+DOCToxicity

Inorganic complexes (E.g. carbonates, hydroxides)

CaMgNaH

2+

2+

+

+

Competition

Organic complexes

toxic action or transport sites

= biotic ligand

(BL)

Cu2+

organism-water interface

Gill Site Interaction Model(Pagenkopf, 1983)

WHAM(Tipping, 1994)

Cu2+

Toxicity

Di Toro et al., 2001 Bioavailability – freshwater

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Validation of bio-availability models - Freshwater (Metal- specific EC EQS guidance)

10

100

1000

10000

10 100 1000 10000

observed EC50 (µg/L)

pre

dic

ted

EC

50 (

µg

/L) Daphnia - acute - Cu

Daphnia - chronic -Cu

Daphnia -acute -Zn

Daphnia - chronic -Zn

Daphnia - acute - Ni

Field cladocerans -acute - CuRainbow trout -chronic - Zn

Metal pH Ca, mg L-1 DOC, mg L-1

Cu 6.0-8.5 3.1-93 (160) UnlimitedNi 6.5-8.2 (8.7) 3.8-88 UnlimitedZn 6.0-8. 2 (8.5) 5.0-160 Unlimited

Boundaries for the Biotic Ligand Model (BLM)

BLM applications to chronic freshwater EQS

Site-specific Cu EQSIf info on pH, DOC and

hardness

User-friendly tool : http://bio-met.net

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Bioavailability – freshwater

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Conclusion long term water EQS values Cu and Zn examples

AA- EQS freshwater

Norway EQS proposal

Comment

Cu 7.8 7.8+ Bio-availability correction (BLM)

Zn 10.9 10.9+Bio-availability correction (BLM)Background correction

Bio-availability : BLM

Background correction

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Setting the marine EQS

Marine EQS setting

Zinc

- NOECS for >40 species

- marine mesocosm = NEW

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Copper

-NOECs for 24 species

- marine mesocosm =NEW

- bio-availability correction

Marine EQS

Marine bio-availability correction(Metal- specific EC EQS guidance)

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Freshwater and marine organisms face very different iono- and osmoregulatory issues related to living in either a very dilute or concentrated salt environment. = freshwater BLMs can NOT be used for marine environments

Marine fish do also suffer from osmoregulatory disturbances under metal exposure and, therefore, similar toxicity mechanisms may apply

= assess marine bio-availabilty corrections

Marine EQS- bioavailability

Scientific evidence for marine bio-availability correction

…copper example

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1

10

100

0.1 1 10

(active) Dissolved Organic Carbon (mg/l)

No

rma

lise

d E

C5

0 (

μg

/l)

Fucus vesiculosis

Crassostreas gigas

M. galloprivincialis

Mytilus edulis

D. excentricus

S. purpuratus

y = 16.715x0.6136

R2 = 0.7662

Marine EQS- bioavailability

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Conclusion long term water EQS values Cu and Zn examples

AA- EQS marine water

Norway EQS proposal

Comment

Cu 2.6 5.2 + Mesocoms study+ DOC correction

Zn 3.4 6.9+ Mesocoms study+ background correction

New research data : mesocosm

Bio-availability : OC correction

Background correction

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Setting the sediment EQS

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Sediment EQS setting (Metal- specific EC EQS guidance

1. Freshwater EQS and Kd values…copper example

- Freshwater suspended matter   30,246 l/kg

- Estuarine suspended matter        56,234 l/kg

- marine suspended matter           131,826 l/kg

2. Sediment EQS and SSD …. zinc example

- Updated data-set – sediment toxicity

- Kd zinc under revision

Sediment bio-availability(Metal- specific EC EQS guidance)

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Sediment bioavailability corrections :

- Organic carbon normalization (cfr organic substances)- Insoluble MeS are formed in anaerobic conditions =

correction for metal-sulfides, measured as “Metals bound to Acid Volatile Sulfides -AVS”

for Zn, Cd, Pb, Cu, Ag, Hg Metal sulphide solubility products Log K(a) Log K(b)

MnS (s) -19.15 - 13.50

(amorphic) -21.80 -

(s) -22.39 -18.10

(s) -27.98 -

ZnS (s) -28.39 -24.70

CdS (s) -32.85 -27.00

PbS (s) -33.42 -27.50

CuS (s) -40.94 -36.10

Ag2S (s) -50.10

HgS -57.25 -52.70 Bioavailability – sediments

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Conclusion sediment EQS values Cu and Zn examples

EQS freshwater sediments EQS marine sediments

EQS Norway proposal

Comment EQS Comment

Cu 210 87+SSD and Bio-availability correction : OC and AVS

84 676+Mesocosm, Kd marine and Bio-availability correction : OC and AVS

Zn 139 147+Updated data-setBio-availability correction : OC and AVS

340 159+Mesocosm, Kd marine and Bio-availability correction : OC and AVS

Revised databases; Kd value marine; Bio-availability : OC and AVS Background correction

Summary and conclusions

Thanks

Most up to data information needed for WFD compliance checking

Bio-availability is important to reduce uncertainty

Evidence to be provided

• by metal

• by species

• by compartment

Practically

• Freshwater : http://bio-met.net

• Marine water : DOC

• Sediment : OC and AVS

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1. Comparison with generic EQS

2. Use of screening tool

3. Consideration of local ambient background concentrations

4. Remedial measures

Pass

Pass

Pass

2. Use of user-friendly BLM

EXCEEDANCE

EXCEEDANCE

EXCEEDANCE

No further action necessary

Prog

ram

mes

of

mea

sure

sCl

assifi

catio

n

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THANKS

For more information, please contact

Katrien. delbeke@copperalliance .eu