IBRACS. Integrating Bioavailability in Risk Assessment of Contaminated Soils: opportunities and feasibilities

Transcription

1 IBRACS Integrating Bioavailability in Risk Assessment of Contaminated Soils: opportunities and feasibilities Period: Oct 2011-Sep 2014; Total founding: National founders: Formas & SGI (Sweden), ADEME & INRA (France), OVAM (Flanders), DGARNE (Wallonia) Dan Berggren Kleja (coordinator), Swedish Geotechnical Institute (SGI) / (IVL on subcontract) Jurate Kumpiene, Luleå University of Technology (LTU) Gerard Cornelissen, Stockholm University (SU) / (NGI on subcontract) Erik Smolders, Katholieke Universiteit Leuven (KUL) Philippe Sonnet, Université Catholique de Louvain (UCL) Thibault Sterkeman, Institut National de la Recherche Agronomique (INRA) Titel

2 Why account for bioavailability? To improve accuracy in risk assessments giving more reliable decisions on how much soil that needs to be remediated. To open up for management options based on immobilization of contaminants (reducing bioavailability). More cost effective site management?

3 Aims IBRACS The overall aim of IBRACS is to provide policymakers, other authorities and service providers with guidelines on how bioavailability tests can be used for risk-based management decisions on contaminated land.

4 Major deliverable IBRACS A handbook on how to use chemical bioavailability tests in risk assessment models for contaminated land Example

5 Project structure IBRACS WP1. Project management SGI WP3. Comparison of SGI existing risk assessment models for soil with focus on bioavailability WP4. KUL Ecotoxicity and bioavailability testing WP5. Uptake of pollutants by plant and bioavailability INRA metals, PAH Zn, Cu, Ni, PAH PAH WP6. Incorporating soil LTU chemical tests in a unified risk assessment framework WP6. Application of unified risk assessment framework on some contaminated sites cost benefit analysis PAHs - Enchytraeidae test Metals - plant test WP2. Dissemination and Exploitation SGI

6 Results

7 Existing RA models (WP3) Country Flanders Wallonia France Sweden Is the option of soil property correction incorporated into the existing soil quality criteria (SQC)? Are there any official guidelines regarding the use of bioavailability methods in site specific ERA? Organic Metals Organic Regression with Regression with No No organic matter clay, organic (1-10% ) matter and ph (only Cu and Zn) No No No No No No No No No No No No Metals The Netherlands Regression with organic matter Regression with clay and organic matter (13 metals). Derived for background sites. Two approaches: 1) pore water concentration; 2) "potential" concentration in soil No

8 Toxicity and plant uptake of PAHs (WP4&5) 4 coking plants, 3 gaswork plants, one old tar factory Site Organic C (%) Black C (%) PAH16 (mg/kg) Experiment(s) France Tox / plant uppt. France Tox / plant uppt. France Tox / plant uppt. France Tox / plant uppt. France Tox / plant uppt. Belgium Tox / plant uppt. Karlstad x Tox / plant uppt. Riksten x Tox Collaboration with PACMAN on France4, Karlstad and Riksten sites Oxy-PAHs analyzed in all ecotoxicity experiments.

9 Method for porewater determination of PAHs equilibration with polyoxymethylene membrane (POM) Anal. Chem. 2011;83(17): Advantages: 1. Cheaper and easier than measuring soil concentrations 2. Measures porewater concentration (better measure?) 3. Disadvantage: longer shaking time Simple method! 2 g soil g POM + 30 ml 0.01 M CaCl 2 + NaN 3 Shake for 1 month, extract POM (membrane) C pw = K POM * C POM

10 The theory behind the method - equilibrium partition theory Will it hold for soils? Cell membrane Pore water Soil organic matter K LIPID K TOC Mineral

11 Biouptake experiments with Enchytraeus crypticus (4 weeks exposure) Results indicate equilibrium between soil, porewater and worms

12 Future work on ecotoxicity Results will be compared with other toxicity data for E. Crypticus evaluate the equilibrium partition theory and the toxic unit approach (paper) Recommendations on how to use the POM method in RA. Draw on previous recommendations; US EPA (EPA-600-R /2003), RIVM (reports /2012, /2012) (handbook)

13 Total PAH root concentration (µg/g) Plant uptake of PAHs by Zea mays (5 weeks growth) 1.E+04 1.E+03 Root uptake FR BE01 SW 1.E+02 1.E+01 1.E+00 1.E-04 1.E-03 1.E-02 1.E-01 1.E+00 Total PAH pore water concentration (POM) (µg/ml) Uptake cannot be desribed as a simple partitioning POM method does not work

14 Plant uptake of PAHs by Zea mays (5 weeks growth) Root uptake Total concentration works better!

15 Future work on plant uptake PAH analysis of shoots Tenax extraction of PAHs in soils Common existing empirical models for plant uptake of PAHs will be evaluated Publication of results (paper) Recommendations on how to use soil tests to predict plant uptake of PAHs; based on this study and literature (handbook)

16 Toxicity of metals to plants (WP4) <1999: Total metal concentrations in soil poorly predict toxic effects : bioavailability models validated for ecotoxicity of Zn, Cu, Ni, Co, Pb in soil; accepted for REACH and included in Flanders for clean up standards of Cu, Zn and Ni. Smolders et al. ET&C 2009

17 Objectives: test toxicity of metals in field contaminated soils and verify which extraction method determines the available metals 10 field contaminated soils 10 corresponding metal salt spiked soils 6 extraction methods on the 20 soils Former mining and smelting sites Wood impregnation site One geogenically enriched site 17

18 field contaminated spiked mg Zn/kg dm g Zn/kg dm

19 Relative yield (%) Aqua Regia Zn (mg/kg dm) EC50 Zn (field) = mg/kg dm EC50 Zn (spiked) = 1665 mg/kg dm Total zinc in spiked soil 22-fold more toxic and available than that in field contaminated soils 19 19

20 Default factor in REACH methods Soil Principal metal EC50 spiked EC50 field contaminated Field/spiked factor * Ba S Zn LC S Zn Pl S Zn 1400 $ 8140 $ 6.0 Scl S Zn Pr S Zn Mo S Zn Au S Zn Bj S Cu Lo S Cu Be S Ni $ EC20 * EC50 field contaminated/ec50 spiked

21 Soil extractions Extractant Extraction-mechanism So called fraction Reference Boiling aqua regia 1:60 Dissolution of oxyhydroxide & carbonates Mineralisation OM Desorption of metals pseudo-total metals (silcates not dissolved) - Cold HNO 3 (0.43 M) 1:10 Dissolution of oxyhydroxide & carbonates Desorption of metals reactive metals (precipitated + exchangeable) Houba, 1998 Cobalithexamine* (0.016M) 1:10 Cation-exchange reactions exchangeable metals Ciesielski & Sterckeman, 1997 NH 4 NO 3 (1M) 1:2.5 Cation-exchange reactions exchangeable metals ISO 19730:2008. EDTA (0.05 M) 1:10 Ligand complexation labile sorbed metals Quevauviller, 1998 Ca(NO 3 ) M 1:10 with 70 Zn, 62 Ni and 65 Cu * Cobaltihexamine: further called Cohex Isotopic Exchange reactive metals Marzouk et al

22 Soil Principal metal EC50 spiked EC50 field contaminated Field/spiked factor * Ratio: Total metal: labile metal Ba S Zn LC S Zn Pl S Zn 1400 $ 8140 $ Scl S Zn Pr S Zn Mo S Zn Au S Zn Bj S Cu Lo S Cu Be S Ni $ EC20 * EC50 field contaminated/ec50 spiked Isotopically exchangeable Zn explains the F/S factor for Zn 22

23 Thus: labile metals rather than total metals can be advocated to enter in soil limits and can be combined with PNEC calculator $ Proposal for implementation Accept models $ developed for REACH except for the default field-spike factor Enter labile metal instead of total metal, labile determined isotopic exchangeable metal Requires: ICP-MS and stable isotopes ( 70 Zn, 65 Cu and 62 Ni) $ Software+ data free at 23

24 Does it pay to account for bioavailablity? (WP6) A cost-benefit analysis of including bioavailability tests in site specific risk assessment will be performed. One site will be Karlstad, Sweden, contaminated with PAHs. On-going collaboration with Karlstad municipality. Other sites are being discussed.

25 Budget, resources Budget of IBRACS (total ): Budget INRA SGI LTU SU/NGI KUL UCL Snowman Total budget Remaining budget

26 Communication and dissemination

27 Communication, internal - actions realised Project kick-off, Stockholm, Oct All-projects kick-off meeting, Paris, Nov Video conference, Oct Project meeting, Nancy, June 2013 All-projects mid-term meeting, Paris, Nov ( , telephone)

28 Communication, dissemination - actions realised Poster presentation of IBRACS on AquaConSoil, April 2013 (SGI) Oral presentation of metal toxicity work on ICOPTE, June 2013 (KUL, UCL) Report on metal toxicity work to the Walloon regulator, October 2013 (in French) (UCL, KUL) A review on methods to assess soil-plant transfer of metals, sent project board March 2013 (INRA) Annual reports to project board members

29 Communication, dissemination - actions planned Two meetings/workshops are going to be held with Walloon and Flemish regulators (UCL, KUL) On national levels, one-day workshop/seminar with (all) stakeholders will be organised by IBRACS members. A final international workshop with (all) stakeholders, likely as a webinar, will be organised early autumn Handbook, 3 papers, conferences Final project report, 30 September 2014