ssd's, soil quality triad and...

1 November 2019

The Soil Quality Triad as an ecological risk assessment tool for supporting soil management at contaminated sites

[email protected]

[email protected]

SESSS 14, November 2019

RIVM National institute for Public Health and the Environment

We advice ministries:

● Health (Health Welfare and Sport; VWS)

● Environment (Infrastructure and Water Management; IenW)

● Agriculture (Agriculture, Nature and Food quality; LNV)

We advice regional governments:

– Provinces

– Municipalities

– Waterboards

We:

o RIVM employees: ~ 1450

o RIVM professors: ~ 28

National Institute for Public Health and the Environment2

3 SSD's, Soil Quality Triad and beyond | November 2019

Content

1. History and background

2. Ecological risk assessment in soil policy

3. WoE with the TRIAD – Scaling and weighing

– 3x LoE

– Tables, tiers and decisions

– Example Brasil

– Spatial aspects

4. Current status

4

Milestones in Dutch soil protection policy

1979: ‘LEKKERKERK’

first case of soil remediation

1987: Soil Protection Act (SPA)

Art 1: soil organisms need to be protected

because of functional role in soil quality

1994: Revision SPA: Target + Intervention Values

Remediation priority system for contaminated sites

2006: Maximum values

2006: Remediation criterion for contaminated sites

2021: End of SPA

→ Environment and Planning Act

http://www.google.nl/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=M6NUre3F8-d4LM&tbnid=4giGmBhwh0b6pM:&ved=0CAUQjRw&url=http%3A%2F%2Fwww.anp-archief.nl%2Fpage%2F92824%2Fnl&ei=rZkUUpGOAeyZ0QWIpoGoCw&bvm=bv.50952593,d.d2k&psig=AFQjCNGeWEEntZd9-oQgx1Q245ppqMcsiw&ust=1377168156136762

5

Potentially

425,000 sites

seriously-contaminated

1518 ‘urgent’ sites (2014)

www.compendiumvoordeleefomgeving.nl

Contaminated sites

6

maximum

value *intervention

value

0

‘suitable quality’

related to land use

(slightly)

polluted

seriously

polluted

Overview current framework

background

value

Remediation

criterion

* Maximum values are depending on land-use

7

‘Remediation Criterion’ for contaminated sites

Separate focus on three different ‘risks’:

• human risks

• ecological risks

• potency for dispersion and migration of contaminants

There are risks, unless…... (precautionary principle)

Tiered procedure:

1. Intervention Value is the threshold

2. Standard site-specific risk assessment (generic set of tools)

3. Tailored site-specific risk assessment

8

Tier 1: Ecotoxicological fundament to protect soil

0

0.2

0.4

0.6

0.8

1

Concentration in soil (mg/kg)

PA

F (

po

ten

tia

lly a

ffec

ted

fra

cti

on

)

1 10 100 1000HC 50HC5

NOEC-

values

HC50HC50

0.2

0.4

0.6

0.8

1


PA

F (

po

ten

tia

lly a

ffec

ted

fra

cti

on

)

1 10 100 1000HC 50HC5

NOEC-

values

0

0.2

0.4

0.6

0.8

1

Concentration in soil (mg/kg)Concentration in soil (mg/kg)

PA

F (

po

ten

tia

lly a

ffec

ted

fra

cti

on

)

1 10 100 1000HC 50HC5

NOEC-

values

HC50HC5

Soil biodiversity model:

SSD integrates

multiple ecosystem

attributes into a

single risk number

HCx key tool in SPA

Van Straalen, Denneman (1989)

Ecotox Env Saf 18: 241-251

Posthuma, Suter, Traas (2002) Species

sensitivity distributions in ecotoxicology

(book).

9

Tier 2: standard site-specific risk assessment‘multi-substance risk assessment’

Criteria:

• Toxic Pressure of mixture (TP)*: 0.25 or 0.65 msPAF

• Surface area: 50, 500, 5000, 50000 m2 *

• Ecological sensitivity: classes: 1, 2 or 3

Assessment:

0.25 or 0.65 msPAF contour exceeds specified surface area

(1.nature, 2.residential/agriculture/parks, 3.industrial/infra).

* Examples of TP calculations in RIVM report 711701072

10

Decision criteria tier 2 Remediation Criterion

Land use type Unsealed surface area

TP > 0.25

Unsealed surface area

TP > 0.65

1.Nature, incl areas in the

Ecological Main Structure

and Natura-2000 areas500 m2 50 m2

2. Agriculture, garden,

residential with garden,

allotments, vegetable

gardens, green areas with

nature values (e.g. park)

5000 m2 500 m2

3. Other green areas,

urban areas, industry,

infrastructure50.000 m2 5000 m2

11

Drawing contours in tier 2

12

Tier 3: generic → site-specific tools

Tier 1 and 2: substance orientation (bioavailability is not considered)

Technical issues:

• Specific land-use, ecosystem services, type of ecosystem, soil type, more impacts, ….

• additional tools: exposure models, specific SSD, bioassays, biomarkers, field surveys, omics, …..

Policy issues:

• shift of responsibility to local government

• site-specific aspects: approval by national and local authorities

→ Negotiation required / policy decisions !

13

What is risk assessment ?

Technical scientific support for

decision-making under uncertainty

• implies a decision (yes or no)

• implies goals

• implies alternative possible outcomes

Suter et al. 2000. Ecological risk assessment forcontaminated sites. CRC press

http://www.google.nl/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=QJv_lEsrFL_hmM&tbnid=BNvEvXlfxa19lM:&ved=0CAUQjRw&url=http%3A%2F%2Fayay.co.uk%2Fart%2Foptical_illusion%2Fscott_kim%2Ftrue-false%2F&ei=uHYTUtWIFcLb0QXRlIDgBw&bvm=bv.50952593,d.d2k&psig=AFQjCNHyF-XYm5wpm8TtkLz5mWvn4GGMlA&ust=1377093683370000

14

1. Uncertainty from variation and lacking data

• Spatial

• Temporal

• Reliability, confidence

2. Uncertainty from ignorance (model uncertainty)

– Unknown effects

– Undefined endpoints, criteria

– Imperfection of indicators

– System’s complexity

Uncertainty in ecological risk assessment

chemistry

risk

toxicity ecology

TRIAD (history)

1985: Edward Long and Peter Chapman introduced the

Sediment Quality TRIAD

1995: Piet den Besten (RIZA) published TRIAD protocol for

sediments in the Netherlands

1999: RIVM publication of Soil Quality TRIAD

2009: TRIAD in Soil Protection Act chemistry

risk

toxicity ecology

https://www.google.nl/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&ved=0ahUKEwizka2ql-bMAhVMtBQKHXx4AZgQjRwIBw&url=https%3A%2F%2Fwww.researchgate.net%2Fpublication%2F240520070_Weight-of-Evidence_Issues_and_Frameworks_for_Sediment_Quality_And_Other_Assessments&bvm=bv.122448493,d.ZGg&psig=AFQjCNGxkIGUs6QEPOfboFO3QgYFpNQjnA&ust=1463748791254417

16

2010: NEN 57372017: ISO 19204

TRIAD standards

https://www.iso.org/standard/63989.html.

decision:

yes or no

ERA

Step 4: determine relevant land use

(current and future land use)

Step 5a: determine ecological requirements

Step 5b: construct conceptual model

Stap 5c: determine assessment endpoints

Step 5e: assessment: testing, evaluation,

data integration, discussion, conclusions

Step 5f: iteration: modification principles,

next tier (steering committee’s consultations)

Step 6: consequence analysis,

recommendations (measures, monitoring)

decision:

yes or no

measures

Step 7: judgment steering committee

Step 8: Design and implementing measures,

after care, communication, monitoring

Step 1: inventory of

environmental issues

at contaminated site

Step 2: selection of

relevant parties

(stakeholders)Step 3: erection of

steering committee for

contaminated site

✓

&

✓

✓

✓

✓

✓

✓

&

✓

✓

✓

&

✓ = input is common and required & = input not essential, but warmly acknowledged

✓

Step 5d:

determine

criteria +

thresholds

references

scaling

weighting

uncertainty

Contribution of

stakeholders

authorities,

land users,

land managers,

proprietor

Contribution of

risk assessors

researchers,

experts,

consultants

decision:

yes or no

ERA












decision:

yes or no

measures








relevant parties



contaminated site

✓

&

✓

✓

✓

✓

✓

✓

&

✓

✓

✓

&


✓

Step 5d:

determine

criteria +

thresholds

references

scaling

weighting

uncertainty

Contribution of

stakeholders

authorities,

land users,

land managers,

proprietor

Contribution of

risk assessors

researchers,

experts,

consultants

decision:

yes or no

ERA












decision:

yes or no

measures








relevant parties



contaminated site

✓✓

&&

✓✓

✓✓

✓✓

✓✓

✓✓

✓✓

&&

✓✓

✓✓

✓✓

&&


✓✓

Step 5d:

determine

criteria +

thresholds

references

scaling

weighting

uncertainty

Contribution of

stakeholders

authorities,

land users,

land managers,

proprietor

Contribution of

risk assessors

researchers,

experts,

consultants

17

Fit for use in decision support

• Quantitative (…… for decision support)

• Tiered approach (…… cost effective: each step adds new info)

• Ecological relevant (…… for the land use: → antropocentric)

Ingredients

• Standard scale: 0 – 1 (no effect - maximum effect)

• integration per TRIAD LoE individually (weight issues)

• Decision after sufficient reduction of uncertainty

TRIAD requirements

chemistry

risk

toxicity ecology

Scaling

● Process of putting information on an ‘effect’ ruler

● Ruler runs from 0 (no effect) tot 1 (maximum effect level)

● 0.5 level is orientation for all TRIAD legs

SSD's, Soil Quality Triad and beyond | November 2019

18

chemistry

risk

toxicity ecology

Scaling





19

chemistry

risk

toxicity ecology

Log [contaminant]

eff

ect

0

1

Scaling





20

chemistry

risk

toxicity ecology

% inhibition in Microtox

eff

ect

0

1

100

Scaling





21

chemistry

risk

toxicity ecology

eff

ect

0

1

% induction of stress genes % survival

max00 100

Adaptationof scaling with SSD

SpeciesSensitivity Distribution

chemistry

0

0.2

0.4

0.6

0.8

1


PA

F (

po

ten

tia

lly a

ffe

cte

d f

rac

tio

n)

1 10 100 1000HC 50

SSDEC50

SSDNOEC

NOEC → EC50

SpeciesSensitivityDistribution

Use of SSD inmulti-substancemodelling

chemistry

23

msPAFEC50

Toxic Pressure calculation of mixture at EC50-level:

= 1 - ((1 - PAF1)(1 - PAF2)…..(1 - PAF n))

0

0.2

0.4

0.6

0.8

1


PA

F (

po

ten

tia

lly a

ffe

cte

d f

rac

tio

n)

1 10 100 1000HC 50

Cu-SSDEC50

Cd-SSDEC50

24

Scaling bioassay information

• Assay with whole organisms → fraction of reduction, inhibition, etc

• Multi-species test, microcosm, model ecosystems, → follow ecology for scaling in multi-attribute systems

• Scaling depends on the level of the response: whole organism versus sub-cellular

• > 5 test results: SSD approach is possible(described in Posthuma et al. (2002)

toxicity

25

ecology

Scaling ecological observations

Often multiple attributes are determined: for instance species composition

All responses determine the overall effect

species 2

total numbers 1+2

[stress]

26

Opt 1: Biological quality index*

All effects (+ and -) are considered as an impact

BQX = 1 – 10

| log Xn |

n

observation X10

0

1

_(REF = 1)

effect

*Schouten et al. 2002

RIVM report 607604003

ecology

27

Opt 2. Multivariate space

ED = k(yki - ykj)2

Distance:

7 km

20 km

28 km

100 km

200 km

-0.6 0.8

-0.6

1.0

70.179

80.19090.171

160.187

170.208

180.202

25.10.18

260.206

270.179

340.141

350.203

360.159

430.185

440.149

450.192

Euclidean Distance between

community compositions of

contaminated and reference site*

ecology

* Data from transect Cu-Ni smelter (Kola

peninsula, Russia; Naumova et al. 2004)

Weighing:

● Process of giving a relative importance to different sources of information: necessary for preparing a decision

● Example: Intervention value based on SSD:

Each species exhibitsa different sensitivity for a contaminant, …..but is equally important for the risk assessment

(Posthuma, Suter and Traas. 2002)


chemistry

risk

toxicity ecology

29

The issue of weighing

Between TRIAD LoEs

• (default) equal weights: chemistry = bioassays = ecology

• (alt) with highly disturbed sites give ecology a lower weight

Within a TRIAD LoE

• (default) all organisms are un-equal, but equally important’ (cf. SSD)

• (+) high weights for specific groups (functional, taxonomic)

• (+) high weights for target species (protected species)

• (+/-) low weights for untrustworthy results, high weights for clear results (provide arguments)

→ Using information(data) = (implicitly) weighing information

30

risk 0 - 0.2

risk 0.2 - 0.5

risk 0.5 - 1

Triadaspect Parameter Sample

A B C

Chemistry SumTP metals 0.00 0.49 0.77

Toxicology Microtox 0.00 0.95 0.95

Ecology nematods biomass 0.00 0.00 0.68

Integrated risk 0.00 0.70 0.83

deviation 0.00 0.82 0.27

TRIAD: tiers and tables (basic level; tier 3a)

Deviation factor is go/no-go trigger

Bornia site; RIVM-report 711701026 (2001)

31

TRIADTier 3c

Triad Aspect Parameter A B CChemistry TP bioavailable 0.00 0.54 0.71


Bait lamina test 0.00 0.42 0.64

Worms growth 0.00 0.02 0.06

Worms survival 0.07 0.15 0.67

Worms reproduction 0.00 0.93 0.97

Lettuce germination 0.00 0.52 0.09

Lettuce growth 0.00 0.26 0.60

integration 0.01 0.65 0.75

Ecology Arthropods asex. reprod. 0.00 0.64 0.50

Arthropods fungiv. grazers 0.00 0.86

Arthropods predators 0.00 0.28 0.82

MO thymidine incorp. 0.00 0.72 0.99

MO biomass 0.00 0.81 0.78

MO nitrification 0.00 0.50 0.00

protozoans 0.00 0.00 0.00

nematods biomass 0.00 0.00 0.68

nematods MI 0.00 0.00 0.65


chemical risk: 0.00 0.54 0.71

toxicity risk: 0.01 0.65 0.75

ecology risk: 0.00 0.42 0.76


deviation 0.01 0.20 0.04

Triad Aspect Parameter A B CChemistry TP bioavailable 0.00 0.54 0.71


Bait lamina test 0.00 0.42 0.64

Worms growth 0.00 0.02 0.06

Worms survival 0.07 0.15 0.67

Worms reproduction 0.00 0.93 0.97

Lettuce germination 0.00 0.52 0.09

Lettuce growth 0.00 0.26 0.60


Ecology Arthropods asex. reprod. 0.00 0.64 0.50

Arthropods fungiv. grazers 0.00 0.86

Arthropods predators 0.00 0.28 0.82

MO thymidine incorp. 0.00 0.72 0.99

MO biomass 0.00 0.81 0.78

MO nitrification 0.00 0.50 0.00

protozoans 0.00 0.00 0.00

nematods biomass 0.00 0.00 0.68

nematods MI 0.00 0.00 0.65


chemical risk: 0.00 0.54 0.71

toxicity risk: 0.01 0.65 0.75

ecology risk: 0.00 0.42 0.76


deviation 0.01 0.20 0.04

Images courtesy Prof. Fernando Carvalho

Metal smelter,

lead and other metals

Santo Amaro,

Bahia, Brazil

● Tier 1: Niemeyer et al. 2010. J Soils Sediments 10:1557–1571

● Tier 2: Niemeyer et al. 2015. PLoS ONE 10(11): e0141772

Example from Brazil

The study site: location and history

Images courtesy Prof. Fernando Carvalho

Smelter area, 1990

“Encapsulated” taillings, 2002

Failed attempt to encapsulate the residues

500.000 metric tons ofresidues with 2-3% Pb

How the site looks todayEvidence of transport of

contaminants

Images: Júlia Niemeyer

35

Sampling scheme

Tests tier 1:

Chemistry:

● Total concentrations

● Mixture modelling

36

Toxicology:

● Avoidance test Folsomia candida

● Avoidance test Eisenia andrei

● Daphnia Magna lethal test

● Vibrio fischeri(Microtox)

Ecology:

● Vegetation cover

● Bait lamina

● Basal soilrespiration

chemistry

risk

toxicity ecology

Risk calculations and results tier 1


Results tier 1 (infographics)


Tier 2, additional tests

39

Chemistry:

● Total concentrations

● Mixture modelling

● Extractable metal concentrations

Toxicology:

● Reproduction test Folsomia candida

● Reproduction test Eisenia andrei

● Reproduction test Enchytraeus

● Daphnia magmareproduction test

● Microalgeagrowth test

● Plant growth test (Avena)

Ecology:

● Surface dwellinginvertebrates

● Microbial biomassC and N

● Enzyme activities

● Litter bags

chemistry

risk

toxicity ecology

Risk calculation and results tier 2

Chem LoE

(total metals)

Chem LoE

(Extractable

metals)

Combined

Ecotox LoE

(retention

function)

IR

(Retention

Function)

Combined

Ecotox LoE

(habitat

function)

Combined

Ecol LoE

(habitat

function)

Group 1

1000T1 0.00 0.99 0.91 0.96 0.63 0.37

20T3 0.23 0.00 0.00 0.00 0.32 0.46

400T3 0.05 0.00 0.00 0.00 0.28 0.44

Group 2

P0 0.85 0.00 0.06 0.03 0.12 0.69

20T1 0.25 0.00 0.12 0.06 0.16 0.63

150T1 1.00 1.00 0.32 0.99 0.71 0.69

50T3 1.00 0.44 0.04 0.27 0.29 0.62

Group 3

50T1 0.19 0.00 0.10 0.05 0.17 0.67

400T1 0.49 0.00 0.07 0.03 0.02 0.37

150T3 0.72 0.00 0.04 0.02 0.41 0.47

1000T3 0.06 0.00 0.02 0.01 0.21 0.38

40

Metal rich tailingsFailed

encapsulation

Impact on establishment of

vegetation

Simplification of habitat structure

Impact on organic matter

input

Lack of favorable conditions for

microorganisms and soil invertebrates

Impairment of soil processes

Ecological risk inside the smelter area

Direct toxicity

Conclusions Santo Amaro

● Uncertainty reduction through Weight of Evidence (WoE)

confirmed for Santo Amaro site

● Many tests are applicable:

no inherent difference between Europe (NL) and Brazil !

● TRIAD approach substantiates risk assessment:

→ ecotoxicological and ecological observations

more convincing for stakeholders

→ clues to better solutions

42

Spatial extrapolation of TRIAD response dataPrecautionary principle less stringent


44

Current status of soil quality TRIAD

● NL: TRIAD is part of the Remediation criterion in the SPA

● NL: 55 TRIADs performed in the Netherlands (until 2008)

85% were useful for decision support

60% of the sites had unacceptable ecological effects

● Many scientific improvements, e.g.:

– Chen et al. 2014. ET&C 33: 900-909

– Sorvari et al. 2013. Risk Anal 33: 203-219

– Gutiérrez, et. al. 2015. STOTEN 514: 49-59

– Ribe et al. 2012. JHazMat 207/208: 15-20

– Dagnino et al. 2008. IEAM 4(3): 314-326

● Technical guidance document (RIVM report 607711003)

● ISO and NEN process standards for TRIAD *SKB 2009 report PTS 808

“Ignorance is inevitable, continuous learning is key” (Aristoteles)

Thanks to our contributors !

NL

● Herman Eijsackers

● Jack Faber

● Jaap Postma

● Dick de Zwart

● Ton Schouten

● Jaap Bogte

● Liesbet Dirven

● Marlea Wagelmans

Contact: [email protected]


Abroad

● John Jensen

● Antonio Marcomini

● Andrea Critto

● Elena Semenzin

● Júlia Niemeyer

● José Paulo Sousa

● Jörg Römbke

47

HC50

Data from 38 sites: Van Wezel et al. (2007) report 500122002 (www.rivm.nl)

chemistry bioassays field observations

serio

us

so

me

cle

an

HC50

AW2000 AW2000

TP (msPAF) effect in bioassays ecological effect

ssd's, soil quality triad and...

Documents