# Prioritisation of soil Contaminants of Emerging Concerns (CECs).

Amélie Cavelan, Aline Coftier

► To cite this version:

Amélie Cavelan, Aline Coftier. Prioritisation of soil Contaminants of Emerging Concerns (CECs). REMTECH Europe 2025, Sep 2025, Ferrara, Italy. hal-05408525

HAL Id: hal-05408525

https://brgm.hal.science/hal-05408525v1

Submitted on 10 Dec 2025

HAL is a multi-disciplinary open access
archive for the deposit and dissemination of sci-
entific research documents, whether they are pub-
lished or not. The documents may come from
teaching and research institutions in France or
abroad, or from public or private research centers.

L'archive ouverte pluridisciplinaire HAL, est
destinée au dépôt et à la diffusion de documents
scientifiques de niveau recherche, publiés ou non,
émanant des établissements d'enseignement et de
recherche français ou étrangers, des laboratoires
publics ou privés.

<figure><img src="image_1.png" /></figure>

Distributed under a Creative Commons Attribution 4.0 International License
<figure><img src="image_2.png" /></figure>

REMTECH
Europe

# Prioritisation of soil contaminants of Emerging Concerns (CECs)

15th of September 2025 at REMTECH EUROPE

Amélie Cavelan, Aline Coftier (BRGM)

<figure><img src="image_3.png" /></figure>

Funded by
the European Union

<figure><img src="image_4.png" /></figure>

Géosciences pour une Terre durable
brgm

Deltares

<figure><img src="image_5.png" /></figure>

GreenDecision

<figure><img src="image_6.png" /></figure>

Syke
## Key objectives

* Provide a EUSO-compatible metadata catalogue of available data and a Roadmap to EUSO-compatible data

* Establish risk-based S-P-R conceptual models in terms of contaminant migration and exposure risks

* Propose methods for remediation objectives with stakeholders

* Propose financial models to promote remediation action

* Propose spatial planning models to prioritize and promote remediation action and reuse of land and soil

* Implementation of ISLANDR outcomes into policy and practice

* Develop a risk-based decision-making framework for both point source and diffuse land contamination

* Provide a long-term platform for the ISLANDR data

## Information-based Strategies for LAND Remediation

Horizon Europe Project ISLANDR | 1 May 2023 - 30 April 2026

<figure><img src="image_7.png" /></figure>

Remediates polluted soils

<figure><img src="image_8.png" /></figure>

Enhances restoration

<figure><img src="image_9.png" /></figure>

Promotes transition of contaminated sites

## Work packages (WP)

<figure><img src="image_10.png" /></figure>
# WHY THIS PRIORITISATION ATTEMPT?

## Main goals and limitations

### BACKGROUND

<figure><img src="image_11.png" /></figure>

* Identifying contaminants of emerging concern (CECs) is needed to support mitigation, regulatory, and monitoring efforts and contribute to the development of an EU priority list for soil.

<figure><img src="image_12.png" /></figure>

→ Prioritisation is needed

### MAIN CHALLENGES

<figure><img src="image_13.png" /></figure>

* **No harmonised list of CECs for soil.**

* **Significant discrepancies in the available dataset of CECs: incomplete or non-existent knowledge.**

* **The few previous prioritisation attempts for soil CECs are often based on **very few substances, prediction models** (black box) that may lead to incomplete or inaccurate risk assessments.**

### AIM & STRATEGY

<figure><img src="image_14.png" /></figure>

* **Use a multi-criteria risk-based procedure using a Source (S) - Pathways (P) -Receptors (R).**

* **Propose a straightforward, reproducible, and easily updatable procedure.**

* **Integrate the assessment of the uncertainty associated with prioritisation due to knowledge gaps and data inconsistencies,**

* **Recommend actions to address these uncertainties.**

<figure><img src="image_15.png" /></figure>
# PRIORITIZATION STRATEGY

## Scoring systems

### Pathways-P

**Mobility risk score (P):**
Risk of soil CEC reaching receptors, impacting environments ubiquitously over the long term

### Source-S

**Soil emission risk score (S):**
Probability of the CEC reaching the soil

Which uses? Which sources?

<figure><img src="image_16.png" /></figure>

1

How much? (REACH tonnage)

<figure><img src="image_17.png" /></figure>

What is the probability of occurrence in soil?

What is the environmental fate? The mobility? The bioaccumulation potential? The persistence?

Soil contaminant?

<figure><img src="image_18.png" /></figure>

<figure><img src="image_19.png" /></figure>

2

Solubility?

Bioaccumulation factors?

Volatility?

<figure><img src="image_20.png" /></figure>

Soil half-life?

Partitioning coefficient?

What are the risks of transfer to other compartments? of reaching potential targets?

### Receptor-R

**Toxicity score (R):**
Probability of CEC creating environmental and health issues

What is the toxicity to humans and the environment?

<figure><img src="image_21.png" /></figure>

3

Classified as PBT?

<figure><img src="image_22.png" /></figure>

<figure><img src="image_23.png" /></figure>

CMR properties?

Environmental toxicity?

What's the risk to create environmental or health issues? Are there any targets to protect?

**Semi-automatic prioritisation and uncertainty assessment in the Excel tool**

<figure><img src="image_24.png" /></figure>

Calculation of the final risk scores

<figure><img src="image_25.png" /></figure>

Risk-based prioritisation: Production of a soil CEC priority list

<figure><img src="image_26.png" /></figure>

**Targets:** Government institutions / decision-makers, and researchers.

**Scale:** National/ European scale => inclusion of diffuse pollution

1. Each parameter used is segmented into classes with risk scores ranging from 0 (no risk) to 1 (maximum risk).

Ex for one parameter used to assess the persistence: Soil half-life (T₁/₂):

<table><thead><tr><td>Soil half-life (T1/2) (days)</td><td>Risk score</td><td>Comments</td></tr></thead><tbody><tr><td>&lt;20</td><td>0</td><td>Very degradable</td></tr><tr><td>20 to 60</td><td>0.25</td><td>Degradable</td></tr><tr><td>60 to 180</td><td>0.5</td><td>Moderately persistent</td></tr><tr><td>≥ 180</td><td>1</td><td>Very persistent</td></tr></tbody></table>

2. The scores of all parameters are combined to obtain the score for each indicator (average scores, maximum score, etc., depending on the indicator).

3. The final priority score is calculated:

<figure><img src="image_27.png" /></figure>

Final priority score = S score * P score * R score
# PRIORITIZATION STRATEGY
## Confidence indicator calculation

### Why?

* Estimate substances with insufficient knowledge to be prioritised,

* Identified the action to be taken to improve our knowledge and prioritisation strategies

### How?

* Calculation of confidence indicators from 0 to 1 to:

* Assess the consistency of the data set for each substance and each parameter: **comparison of different indicators and of data from different sources, when possible** (models, field, experimental data points),

* Counting the **number of missing data points** for each substance.

### One example :

<table><thead><tr><th>Carcinogenicity categories (C&L classification)</th><th>Meaning</th><th colspan="2">Confidence indicator (CI)</th></tr></thead><tbody><tr><td>Recognized: Category 1A</td><td>Proven</td><td>1</td><td>High</td></tr><tr><td>Recognized: Category 1B</td><td>Supposed</td><td>0.8</td><td>High</td></tr><tr><td>Potential (Category 2)/under assessment</td><td>Suspected/ under assessment</td><td>0.5</td><td>Medium</td></tr><tr><td>Broad agreement</td><td>&gt;= 50% of the data submitters providing the same concern</td><td>0.4</td><td>Low</td></tr><tr><td>Minority position</td><td>Between 5 and 50% of the data submitters have provided the concerns</td><td>0.25</td><td>Low</td></tr><tr><td>Not classified</td><td>No risk</td><td>1</td><td>High</td></tr><tr><td>No data</td><td>No information</td><td>0</td><td>Low</td></tr></tbody></table>

Final level of confidence for Toxicity score = average CI of parameters used to assess the risk of toxicity
# PRIORITIZATION STRATEGY
## Confidence indicator calculation

More complex when several parameters and data sources are compared for the same indicator,

For example, the following parameters are used to assess the persistence in soil :

- Biowin3 score (predicted by the US EPI)

- Soil half-life (experimental)

These parameters could:

- agree on whether or not the risk exists

- disagree

- not available (no data)

<figure><img src="image_28.png" /></figure>
# PRIORITIZATION STRATEGY
## Which substances? How to find them?

<figure><img src="image_29.png" /></figure>

To harmonise with the CECs identified and considered priorities in aquatic environments, we chose to start from a **common list** from the NORMAN project. But thousands of CECs...

A limited amount of time to complete this work means a limited number of substances to consider => therefore, preselection **was needed.**

### What about the other CECs and soil-specific pollutants that have not been included in the NORMAN list?

Regular updates of the list until the end of the project, with new substances added from:

* calls for contributions within the ISLANDR project,

* results and publications from ongoing other research projects.

## CECs preselection procedure

### 1. Exclusion of metals and metalloids

<figure><img src="image_30.png" /></figure>

### 3. Clusterisation of retained CECs according to their environmental fate.

50 groups created

<figure><img src="image_31.png" /></figure>

### 2. Automatic search in databases of the physicochemical properties of each CEC and selection of substances that may be soil pollutants.

Thousands of CECs retained.

<figure><img src="image_32.png" /></figure>

Can be a soil pollutant ?

<figure><img src="image_33.png" /></figure>

<figure><img src="image_34.png" /></figure>

### 4. Selection of the most used and most toxic CECs in each group

Start with 74 CECs

<figure><img src="image_35.png" /></figure>
# RESULTS OBTAINED

* Production of an Excel tool used for the prioritisation => will be freely available online on the ISLANDR website

* Production of a prioritised list of soil CECs with the greatest concerns

* Production of a list of CECs for which current knowledge is insufficient for prioritisation and requires further action.

<table><caption>Table 1: Top 15 of the priority list on the 2nd of September 2025.</caption><thead><tr><td>Rank</td><td>CECs</td><td>CAS_RN</td><td>Final priority score</td><td>Confidence indicator</td></tr></thead><tbody><tr><td>1</td><td>Octamethylcyclotetrasiloxane (D4)</td><td>556-67-2</td><td>0.83</td><td>Medium</td></tr><tr><td>2</td><td>Bisphenol A</td><td>80-05-7</td><td>0.56</td><td>Medium</td></tr><tr><td>3</td><td>Galaxolide</td><td>1222-05-5</td><td>0.54</td><td>Medium</td></tr><tr><td>4</td><td>4-tert-Butylphenol</td><td>98-54-4</td><td>0.49</td><td>Medium</td></tr><tr><td>5</td><td>Dibutyl phthalate (DBP)</td><td>84-74-2</td><td>0.38</td><td>Medium</td></tr><tr><td>6</td><td>Tetrabromobisphenol A (TBBPA)</td><td>79-94-7</td><td>0.38</td><td>Medium</td></tr><tr><td>7</td><td>Carbendazim</td><td>10605-21-7</td><td>0.37</td><td>Medium</td></tr><tr><td>8</td><td>Thiacloprid</td><td>111988-49-9</td><td>0.36</td><td>Medium</td></tr><tr><td>9</td><td>Triclosan</td><td>3380-34-5</td><td>0.35</td><td>Medium</td></tr><tr><td>10</td><td>Bromadiolone</td><td>28772-56-7</td><td>0.34</td><td>Medium</td></tr><tr><td>11</td><td>p-t-Bucinal (Lilial)</td><td>80-54-6</td><td>0.32</td><td>Medium</td></tr><tr><td>12</td><td>Difethialone</td><td>104653-34-1</td><td>0.31</td><td>Medium</td></tr><tr><td>13</td><td>PFOA / Acide perfluorooctanoïque</td><td>335-67-1</td><td>0.30</td><td>Medium</td></tr><tr><td>14</td><td>Brodifacoum</td><td>56073-10-0</td><td>0.29</td><td>Medium</td></tr><tr><td>15</td><td>Tonalide / AHTN</td><td>1506-02-1</td><td>0.28</td><td>Medium</td></tr></tbody></table>

<table><caption>Table 2: List of CECs with insufficient knowledge for prioritisation on the 2nd of September 2025.</caption><thead><tr><td>CECs</td><td>CAS_RN</td><td>Final priority score</td><td>Confidence indicator</td><td>Needed data</td></tr></thead><tbody><tr><td>Tolyltriazole</td><td>29385-43-1</td><td>0.42</td><td>Low</td><td>Mobility</td></tr><tr><td>Chlorfenapyr</td><td>122453-73-0</td><td>0.31</td><td>Low</td><td>Emission/Use</td></tr><tr><td>Fenoxycarb</td><td>72490-01-8</td><td>0.31</td><td>Low</td><td>Emission/Use</td></tr><tr><td>Octabromodiphenyl ethers / OctaBDE</td><td>32536-52-0</td><td>0.23</td><td>Low</td><td>Emission/Use, Toxicity</td></tr><tr><td>6:2 FtTAoS</td><td>755698-73-8</td><td>0.18</td><td>Low</td><td>Emission/Use, Toxicity, Mobility</td></tr><tr><td>17-alpha-Ethinylestradiol/ EE2</td><td>57-63-6</td><td>0.17</td><td>Low</td><td>Emission, Toxicity</td></tr><tr><td>Butylated hydroxytoluene / BHT</td><td>128-37-0</td><td>0.15</td><td>Low</td><td>Toxicity, Mobility</td></tr><tr><td>Tetrachlorophthalic anhydride / TECP-Anh</td><td>117-08-8</td><td>0.12</td><td>Low</td><td>Emission/Use</td></tr><tr><td>4-Nonylphenol mono-ethoxylate / NPE10</td><td>104-35-8</td><td>0.11</td><td>Low</td><td>Emission/Use, Toxicity</td></tr><tr><td>OPE10</td><td>2315-67-5</td><td>0.09</td><td>Low</td><td>Emission/Use, Toxicity</td></tr></tbody></table>
* Continuous additions of new substances and updating of data until the end of the project in 2026.

* Expansion of the parameters and amount of data considered for calculating prioritisation scores and level of uncertainty.

<figure><img src="image_36.png" /></figure>

## Example of last updates:

New in!

<figure><img src="image_37.png" /></figure>

* Addition of more than 200 substances since June 2025 in the Excel tool

* Revision of the method for calculating the **Source (Emission) score** to take into account three new parameters:

* **Max range of use index (RoU)** in EU(SPIN database): maximum estimated quantity of the substance used annually,

* **Max use index for soil** in EU (UI) for soil (SPIN database): risk of the substance being released to the soils during use,

* **REACH tonnage of parent products** for substances not directly used, produced or imported in Europe but released in the environment during the degradation of other chemicals,

* Revision of the **Pathways score calculation**:

* Addition of a score indicating whether a substance is **known to degrade into metabolites** that pose a risk (mobile, persistent, toxic, etc.).
# Funding Acknowledgement

Funded by the European Union. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union. Neither the European Union nor the granting authority can be held responsible for them.

<figure><img src="image_38.png" /></figure>

Funded by
the European Union

UK partner in ISLANDR is supported by UKRI grant. Swiss partner in ISLANDR is supported by Swiss grant.

<figure><img src="image_39.png" /></figure>

UK Research
and Innovation

Project funded by

<figure><img src="image_40.png" /></figure>

Schweizerische Eidgenossenschaft
Confédération suisse
Confederazione Svizzera
Confederaziun svizra

Swiss Confederation

Federal Department of Economic Affairs,
Education and Research EAER
State Secretariat for Education,
Research and Innovation SERI

<figure><img src="image_41.png" /></figure>

<figure><img src="image_42.png" /></figure>
<figure><img src="image_43.png" /></figure>

a.cavelan@brgm.fr

a.coftier@brgm.fr

THANK YOU

<figure><img src="image_44.png" /></figure>

contact@islandr-project.eu

<figure><img src="image_45.png" /></figure>

<figure><img src="image_46.png" /></figure>

@islandr-project

<figure><img src="image_47.png" /></figure>

islandr-project.eu