REMEDIATE

Practically implementing the use of Bioaccessibility testing to determine

risks to Human Health

Presenter: Tatiana Cocerva

19th of April 2018

Brownfield & Contaminated Land

I. Importance of Bioaccessibility testing in Human Health Risk Assessment

II. The Unified BARGE Method (UBM)

III. Factors affecting the contaminant bioaccessibility

IV. Generic Assessment Criteria (GAC)

V. Case Study: Oral Bioaccessibility of As, Cr, Ni, and Pbacross the metropolitan area of Belfast

VI. Quantifying the potential saving in remediation costs to be achieved through bioaccessibility testing

Presentation Outline:

Bioaccessibility testing is

used in Detailed

Quantitative Risk

Assessment (DQRA):

- refine the risks posed to

receptors

- better accounting for

uncertainties

- less conservative

- site-specific risk assessment

PreliminaryRisk

Assessment

Genericquantitative

riskassessment

Detailedquantitative

riskassessment

Identification of feasible

remediationoptions

Detailedevaluation of

options

Developing the remediation

strategy

Preparation of the

implementationplan

Design, implementation

& verification

Long-termmonitoring 1 maintenance

Implementation of remediation strategy

RiskAssessment

Options appraisal

Oral Bioaccessibility

The process of managing land contamination

CLR11 – developed by EA and Defra, 2004

I. Importance of bioaccessibility testing in Human Health Risk Assessment (HHRA)

- Soil ingestion scenario

Bioavailability 100%

soil soil

Bioaccessibility

Bioaccessible contaminants measured using the

Unified BARGE MethodContaminants available for

uptake

Non-bioaccessible metals are excreted with undigested soil.

Bioavailability vs Bioaccessibility

StomachPhaseEnd-over-end for 1h, 37°C.

• BARGE – BioAccessibility Research Group of Europe

• UBM is an in vitro method which simulatesthe human gastrointestinal environmentusing 4 synthetic digestive fluids:

- Saliva

- Gastric fluid

- Duodenal fluid

- Bile

Stomach+

Intestinal Phase

End-over-end 4h, 37⁰C

0.4g of soil mixed with 6ml of simulated saliva, pH 6.5 for 10s.

9ml of simulated gastric solution, pH 1.2.

18ml of simulated duodenal fluidand 6ml of simulated bile fluid, pH 6.3.

Soil

%Bioaccessible fraction(𝐁𝐀𝐅) =𝐶𝑜𝑛𝑐𝑒𝑛𝑡𝑟𝑎𝑡𝑖𝑜𝑛 𝑜𝑓 𝑏𝑖𝑜𝑎𝑐𝑐𝑒𝑠𝑠𝑖𝑏𝑙𝑒 𝑚𝑒𝑡𝑎𝑙 (

𝑚𝑔

𝑘𝑔)

𝐶𝑜𝑛𝑐𝑒𝑛𝑡𝑟𝑎𝑖𝑜𝑛 𝑜𝑓 𝑡𝑜𝑡𝑎𝑙 𝑚𝑒𝑡𝑎𝑙 𝑖𝑛 𝑠𝑎𝑚𝑝𝑙𝑒 (𝑚𝑔

𝑘𝑔)

x 100

II. The Unified BARGE Method

UBM - Available at Queen’s University Belfast

StomachPhaseEnd-over-end for 1h, 37°C.

Stomach+

Intestinal Phase

End-over-end 4h, 37⁰C

0.4g of soil mixed with 6ml of simulated saliva, pH 6.5 for 10s.

9ml of simulated gastric solution, pH 1.2.

18ml of simulated duodenal fluidand 6ml of simulated bile fluid, pH 6.3.

Bla

nk

*SG

M

S1 S1 D

up

Bla

nk

SGM

S1 S1 D

up

Bla

nk

SGM

S1 S1 D

up

• BARGE – BioAccessibility Research Group of Europe

• UBM is an in vitro method which simulatesthe human gastrointestinal environmentusing 4 synthetic digestive fluids:

- Saliva

- Gastric fluid

- Duodenal fluid

- Bile

%Bioaccessible fraction(𝐁𝐀𝐅) =𝐶𝑜𝑛𝑐𝑒𝑛𝑡𝑟𝑎𝑡𝑖𝑜𝑛 𝑜𝑓 𝑏𝑖𝑜𝑎𝑐𝑐𝑒𝑠𝑠𝑖𝑏𝑙𝑒 𝑚𝑒𝑡𝑎𝑙 (

𝑚𝑔

𝑘𝑔)

𝐶𝑜𝑛𝑐𝑒𝑛𝑡𝑟𝑎𝑖𝑜𝑛 𝑜𝑓 𝑡𝑜𝑡𝑎𝑙 𝑚𝑒𝑡𝑎𝑙 𝑖𝑛 𝑠𝑎𝑚𝑝𝑙𝑒 (𝑚𝑔

𝑘𝑔)

x 100

*SGM – Soil Guidance Material BGS102; Hamilton et al., 2015

II. The Unified BARGE Method

UBM - Available at Queen’s University Belfast

• The UBM has been calibrated against in vivo data and validated for As, Cd, Pb.

• The UBM will be turned into a full International Standard.

• The last DIS (Draft International Standard) has been published on the 15th of June 2016.

In vitro

In vivo

(Denys et al. 2012)

Why the UBM?

III. Factors affecting the contaminant bioaccessibility

Cave et al., 2011

• Mineralogy

• Particle size

• Encapsulation

• Chemical

Species

• pH

• SOM

IV. Generic Assessment Criteria (GAC)How are derived?

• Derived (in the UK) using the CLEA model and guidance (Environment Agency)

• Default CLEA model assumes 100% (1.0*) for the relative bioavailability (RBA soil, tox) for soil and

for airborne dust.

* C4SL for Pb assumes 60% BAF, Category 4 Screening Level published by Defra, 2014

Basic Setting

Advanced Setting(amend the database)

Database Management(Add info to

database

IV. Generic Assessment Criteria (GAC)S4ULs

Suitable for Use Levels “S4ULs” have been derived and published by the Land Quality

Management (LQM)/ Chartered Institute of Environmental Health (CIEH) 2015.

• Based on Health Criteria Values

• Designed for 6 land use scenarios:

− Residential with homegrown produce

− Residential without homegrown produce

− Allotments

− Commercial

− Public Open spaces near residential housing

− Public Parks

What does exceedance of a soil GAC mean?

• An exceedance means there may be an unacceptable risk to human health, and should

trigger further assessment or remedial action.

• Bioaccessibility testing should be considered.

• Industrial history in linen

production (from early 18th

Century) and shipbuilding

(late 18th Century)

• Varied bedrock geology known to control Potentially Toxic Elements (PTEs) concentrations:

• Basalts to the north

• Sherwood sandstone

• Greywacke to the south

• 100 Tellus samples selected for bioaccessibility testing:

• Shallow samples: 5-20cm

• Include different: land uses,

geology, development zones

V. Case study: Metropolitan area of Belfast

V. Case Study: Oral Bioaccessibility of As across metropolitan area of Belfast

UBM

S4ULs As:• Residential with homegrown produce: 37mg/kg• Residential without homegrown produce: 40mg/kg

V. Case Study: Oral Bioaccessibility of Cr across metropolitan area of Belfast

UBM

S4ULs Cr (III):• Residential with homegrown produce: 910 mg/kg• Residential without homegrown produce: 910 mg/kg

V. Case Study: Oral Bioaccessibility of Ni across metropolitan area of Belfast

UBM

S4ULs Ni:• Residential with homegrown produce: 130 mg/kg• Residential without homegrown produce: 180 mg/kg

V. Case Study: Oral Bioaccessibility of Pb across metropolitan area of Belfast

UBM

C4SL Pb:• Residential with homegrown produce: 200 mg/kg• Residential without homegrown produce: 315mg/kg

V. Case Study: Metropolitan area of BelfastHow is GAC affected?

37 mg/kg

40 mg/kg

UBM

How is GAC

affected?

QUB deriving graphs of GACs for

varying BAF for a variety of

contaminants & land uses based

on S4ULs Methodology adapted

from Scott and Nathanail, 2011

V. Case study: Metropolitan area of Belfast

• Bioaccessibility data for As, Cr, Ni, and Pb present the situation on a large scale in the Metropolitan area of Belfast.

• Site specific risk assessment must be undertaken in the areas of concern.

• Who can potentially use these results?

❖ decision makers

❖ urban planners

❖ regulators

❖ developers of urban areas

VI. Quantifying the potential saving in remediation costs to be achieved through bioaccessibility testing

British Geological Survey has undertaken bioaccessibility testing on two former coal mining sites and one residential area in the UK.

The savings in remediation cost are the following:

Advantages:- Avoid unnecessary remediations- Redevelopment of the brownfields sites -- Remove uncertainties regarding the Human Health Risks from contaminated land

Full report: https://www.bgs.ac.uk/downloads/start.cfm?id=2935

1. CISED sequential extraction for

15 Tellus samples. (Work completed in collaboration with Cranfield University)

2. Develop a sampling technique for bioaccessibility testing using a contaminated site in Denmark. (Work completed in collaboration with University of Copenhagen)

13.

Work in progress:

Remediate: Improved decision-making in contaminated land site investigation and risk assessment

• Marie Skłodowska-Curie Initial Training

Network funded by European Union’s

Horizon 2020 programme

• 13 researchers hosted in UK, Ireland,

Germany, Denmark, and Italy

• Coordinated by the QUESTOR Centre at

Queen’s University Belfast

Oral Bioaccessibility of Potentially Toxic Elements (PTEs) in urban area of Belfast

Belfast Conference in September 2018

Belfast Conference in September 2018

Registration: Public sector / Academic rate

• Early bird : £75 for both days (dinner included)

£50 single day (dinner £25 extra)

• Standard: £100 for both days (dinner included)

£60 single day (dinner £25 extra)

Industry rate

• Early bird: £125 for both days (dinner included)

£75 single day (dinner £25 extra)

• Standard: £200 for both days (dinner included)

£125 single day (dinner £25 extra)

• Science of the Total Environment - Virtual Special Issue

• Top Environmental Journal CiteScore: 5.09 IF: 4.900 SNIP: 1.849 ℹSJR: 1.621

• Submission opens Mid May closes end of June

REMEDIATE Special Issue in STOTEN

Thanks For Listening!

REMEDIATE

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 643087

Project coordinated by the QUESTOR Centre at Queen’s University Belfast www.qub.ac.uk/questor

AcknowledgementsBritish Geological Survey

- Especially Dr. Mark Cave, Dr. Joanna Wragg

Geological Survey of Northern Ireland

- Especially Dr. Robert James Raine, Mr. Alexander Donald, Dr. Marie Cowan

The Institute for Global Food Security, QUB

- Especially Mr. Manus Carey, Prof. Andrew Meharg

QUESTOR CENTER

- Especially Dr. Julie-Anne, Mr. David Parker

RSK

- Especially Lucy Thomas, Joanna Wilding and Frances Gregory

Cranfield University, University of Copenhagen

This work was completed as part of the REMEDIATE (Improved decision-making in contaminated land site investigation and risk assessment) Marie-Curie Innovation Training Network. The network has received funding from the European Union’s Horizon 2020 Programme for research, technological development and demonstration under grant agreement n. 643087. REMEDIATE is coordinated by the QUESTOR Centre at Queen’s University Belfast http://questor.qub.ac.uk/REMEDIATE/

• Cave, M.R., Wragg, J., Denys, S., Jondreville, C., Feidt, C., 2011. Oral Bioavailability, in: Swartjes, F.A. (Ed.), Dealing with Contaminated Sites. Springer Netherlands, pp. 287–324. doi:10.1007/978-90-481-9757-6_7

• Chartered Institute of Environmental Health (CIEH), 2009. Professional Practice Note: Reviewing human health risk assessment reports invoking contaminant oral bioavailability measurements or estimates.

• Denys, S. et al., 2012. In vivo validation of the unified BARGE method to assess the bioaccessibility of arsenic, antimony, cadmium, and lead in soils. Environmental Science and Technology, 46(11), pp.6252–6260.

• Hamilton, E.M. et al., 2015. Bioaccessibility performance data for fifty-seven elements in guidance material BGS 102. Microchemical Journal, 123, pp.131–138. Available at: http://www.sciencedirect.com/science/article/pii/S0026265X1500123X.

• McIlwaine, R., Doherty, R., Cox, S.F., Cave M. R. (2017) The relationship between historical development and potentially toxic element concentrations in urban soils. Environmental Pollution, 220(B): 1036-1049 http://dx.doi.org/10.1016/j.envpol.2016.11.040

• Nathanail, C.P. et al. 2015. The LQM/CIEH S4ULs for Human Health Risk Assessment. Land Quality Press, Nottingham.

• Nelson, C.M. et al., 2013. Evaluation of a low-cost commercially available extraction device for assessing lead bioaccessibility in contaminated soils. Environ Sci Process Impacts, 15, pp.573–578. Available at: http://www.ncbi.nlm.nih.gov/pubmed/23738355.

• Palmer, S., Cox, S.F., McKinley, J.M., Ofterdinger, U., 2014. Soil-geochemical factors controlling the distribution and oral bioaccessibility of nickel, vanadium and chromium in soil. Appl. Geochemistry 51, 255–267. doi:10.1016/j.apgeochem.2014.10.010

• Scott DI & Nathanail CP, 2011. Generic human-health assessment criteria for arsenic at former coking works sites. CL:AIRE Research Bulletin RB14. CL:AIRE, London, UK. ISSN 2047-6450

• Wragg, J. et al., 2011. An inter-laboratory trial of the unified BARGE bioaccessibility method for arsenic, cadmium and lead in soil. Science of the Total Environment, 409(19), pp.4016–4030. Available at: http://dx.doi.org/10.1016/j.scitotenv.2011.05.019

• BGS report: Reducing Land Remediation Costs by applying bioaccessibility testing https://www.bgs.ac.uk/downloads/start.cfm?id=2935

•CLEA Software available to download from: https://www.gov.uk/government/publications/contaminated-land-exposure-assessment-clea-tool

References: