Sub-group on Prioritisation of Emerging Contaminants in Groundwater 1 st meeting - Discussion Dr. Benjamin Lopez (Fr. Geo. Survey) UBA - Bismarckplatz, Berlin-Charlottenburg – Thursday 21 st of April 2015 –

Possible links with EU WG-C activities > Aim of the watch(ed) list: To identify substances those pose a “potential risk to bodies of groundwater”. Whether a substance poses a risk depends on different criteria. Important are the toxicological properties, the persistence of a substance, and the ability to bioaccumulate and so on. Other important criteria are the source or origin of the substances and the amount of a substance that is released to the environment.  May corresponds to Category 1 “Priority for Regular Monitoring” of the NORMAN Prioritisation scheme > What is the role of the NORMAN GW prioritisation group as regards the definition of the GW watch(ed) list? mardi 8 décembre 2015 > 2

Existing prioritisation schemes > The candidate substances are sorted by action categories and then they are ranked within each action category: Cat. 1: Substances for which there is sufficient evidence of exposure and adverse effects at environmental concentration Cat. 2: Substances for which hazard assessment is based on experimental data BUT few monitoring data are available Cat. 3: Substances for which there is evidence of exposure BUT hazard assessment is based on predicted toxicity (P-PNEC) Cat 4: Substances for which hazard assessment is based on experimental data BUT analytical capabilities are not yet satisfactory Cat. 5: Substances for which no or few monitoring data are available AND hazard assessment is based on predicted toxicity (P-PNEC) Cat. 6: Substances for which toxicity data are sufficient for the derivation of an EQS and there is evidence that the exposure does not pose a hazard to ecosystems. mardi 8 décembre 2015 > 3

> Do we agree that a similar approach (prioritisation by action category) could be applied for prioritisation of emerging contaminants in groundwater? Or should we develop a completely different approach? > If we agree on this approach, what are the relevant action categories for CECs on GW? mardi 8 décembre 2015 > 4 Existing prioritisation scheme

Data sources > Data needed: 1) General information on substances and their uses (point sources or diffuse contamination?) 2) Fate in soil and in GW (adsorption constants, DT50, solubility, metabolites etc…) 3) Toxicity and ecotoxicity of substances 4) Current and past regulatory status, period of use, use restrictions, date of withdrawn from the market 5) Raw data on occurrence of CECs in GW 6) … and others? mardi 8 décembre 2015 > 5

> The NORMAN EMPODAT database is a geo-referenced monitoring / occurrence database on emerging substances. EMPODAT contains already datasets on GW but for a limited number of countries. > EMPODAT can be used as a repository tool for datasets of CECs in GW. A reporting data template already exists for GW but it can be reviewed / improved, where needed by the GW Sub-group. > Are there other open access databases available in Europe? 1.1. Does the group agree to share datasets (published data) on CECs in GW to NORMAN EMPODAT? 1.2. Who is willing and can provide datasets on CECs in GW? mardi 8 décembre 2015 > 6 Data sources

Critical issues for GW substances categorisation Assuming that the concept of the existing NORMAN categorisation and prioritisation scheme is adopted, adaptation of this scheme to GW poses several questions: mardi 8 décembre 2015 > 7

What is the universe of chemicals? > As time transfer towards GW may be long (decades and more), particular attention should be paid to former activities  Banned/withdrawn substances. > During their transfer, substances could be degraded in transformation products that can be more toxic/ecotoxic than their parents. As a result, metabolites play an important role in GW quality assessment  Metabolites and transformation products mardi 8 décembre 2015 > 8 Critical issues for GW substances categorisation

What are the relevant indicators that define the “sufficiently monitored and sufficiently quantified substances” in GW? > Level of investigation = N° of countries? Number/Density of sites? Representativeness of the sampling sites (in term of geological context, anthropogenic pressure)? > Occurrence = quantification frequency? Frequency of exceedance of a threshold value? Frequence of exceedance of a fixed value (max LOQ of the data set)? > Level of contamination = statistical distribution of concentrations in GW (centiles, median, standard deviation…) at EU scale. mardi 8 décembre 2015 > 9 Critical issues for GW substances categorisation

How to aggregate heterogeneous MS datasets to produce comprehensive information on potential GW contamination? > Importance of metadata on hydrogeological, hydroclimatic/hydrodynamic and pressure contexts at sample sites > How to take into account different limit of detections/quantification (LOD/LOQ) when working with occurrence data from different sources example of the weighted quantification frequency developed in the French prioritisation scheme mardi 8 décembre 2015 > 10 Critical issues for GW substances categorisation

What are the GW threshold values that can be used to sort substances by action categories? > Many different uses of GW (water supply, Irrigation, River flow supporting…) can be restricted due to the presence of substances. The target is not only de biodiversity of the aquatic environment. For example, GW are often used for water supply without any treatments. So ecotoxicological hazards are not the only parameters that should be taken into account. > Moreover, theoretically there is no direct input in GW, which implies that any presence of anthropogenic substances in GW indicates a transfer issue. Different protection objectives: > protect the uses of GW (protect from CECs concentrations that may prevent the uses of groundwater) > preserve the natural quality of GW (natural chemical state) mardi 8 décembre 2015 > 11 Critical issues for GW substances categorisation

Two options: > Option 1- To define and use the lowest threshold or guide value (worth case scenario): Regulations for drinking water and the foodstuffs Environmental Quality Standards WHO recommendations PNEC: always the worth case? (not for the majority of pesticides); to be used only when a link between surface and groundwater is suspected?  Work needed to build/maintain/update an open access threshold values database (PNEC and other EQS, toxic levels…) same model than ECOTOX DB presented by Peter? But what happens when there is no threshold or guide value? Notably when substances are not regulated? > So only the indicators associated to Level of investigation and Occurrence seem to be relevant for the definition of the action category > BUT how sensitive analytical methods need to become for substances to be monitored in GW? mardi 8 décembre 2015 > 12 Critical issues for GW substances categorisation

> Option 2- To define and use a single threshold value for all substances and consider GW as a “chemical soup”. > Mons et al, (2013) discussed about the use of the 0.1 µg/L TTC value as a target value for all organic compounds in drinking water (1µg/L for the total sum) except for genotoxic and steroid endocrine (0.01 µg/L for individual and sum of compounds) > In this case, we just need to know what is the most present substance in the GW (= occurrence)? (+) Being based on a single reference value, there is no bias associated to different reporting levels (i.e. different data sources / different LODs) (-) All LODs need to be below the reference value  Longer-term action: definition of a GW biodiversity (new specific targets for PNEC GW calculation) mardi 8 décembre 2015 > 13 Critical issues for GW substances categorisation

Finding a unique value that suite for all substances  Assimilating GW as a “chemical mixture” - What are the most present chemicals in GW? Is the 0.1 µg/L value a good reference value? Cf. the use of Threshold of Toxicological Concern (TTC) approach for deriving target values for drinking water contaminants (Mons et al., 2013). 0.1 µg/L used as a target value for all organic compounds in drinking water (1µg/L for the total sum) except for genotoxic and steroid endocrine (0.01 µg/L for individual and sum of coumponds) 0.1 µg/L used as a unique regulated value for pesticides in GW (with some exceptions) 0.1 µg/L is an analytical reporting level easily achievable for numerous laboratories 0.1 µg/L is RL independent (but doesn’t work if RL > 0.1 µg/) ► How can the scoring be done if all the substances have the same hazard? What is “the spirit” of the NORMAN members on this issue? Critical issues for GW substances categorisation

Organisation of the work of the sub-group / next meetings Work / activities organised by NORMAN GW Sub-group should be: > independent of the work of WG-C? > directly in support of EC WG-C? > Should the next NORMAN meeting be organised in advance to next WG-C meeting in order to provide proposals on the Watch(ed) List establishment? > Regular exchanges between the sub-groups leaders? mardi 8 décembre 2015 > 15

List of experts / targeted participants Who (organisme) is interested in participate? > Establish a list of active members committed to participate in the NORMAN GW sub-group. > NORMAN members already interested: UBA (Wolter Rüdiger); BfG (contact person to be confirmed); Danone Group (Lodovico di Gioia)); EAWAG (Juliane Hollender); EI (Jaroslav Slobodnik, Ildi Ipoly); KWR (Stefan Kools ); Suez Env.(ar Esperanza); Middlesex University (contact person to be confirmed??) ; Plastics Europe (James Franklin); Labaqua (Julio Llorca); Fraunhofer Institute (Heinz Ruedel); University of Copenhagen (contact person to be confirmed); IRSTEA (contact person to be confirmed); IVL (Eva Brorstrom Lundén); RECETOX (contact person to be confirmed); VEOLIA (Armelle Hebert); > Non-NORMAN members interested: Ronald Kozel (BAFU) mardi 8 décembre 2015 > 16

Thank you for your attention and interest in groundwater ! mardi 8 décembre 2015 > 17

Starting universe? Pay attention to the time transfer that can be long and the fate of compounds in GW : Forbidden/Banned substances and metabolites ! Source of data? Databases that exhibit occurrence data in GW : River Basin Agency data (GW chemical status) ADES (French national database on groundwater quality) National screening on emerging substances … Indicators that define the suff. monitored and quantified substances? Level of investigation Occurrence

Relevant GW Threshold Values? Major Issue ! There are many different uses of GW Water supply (raw waters) Irrigation Geothermic water River flow supporting … Moreover, there is no direct input in GW (theoretically) ► Any presence of anthropogenic substances in GW indicate a problematic, not only a PNEC overrun Not ecotox. hazard only

Relevant GW Threshold Values? 2 options : 1 - Finding the lowest threshold or guide value (worth case) Human health Drinking water regulations Food safety regulations Environmental Quality Standard values World Health Organization recommendations PNEC always the worth case? (not for several pesticides) to be used only when a link between surface and groundwater is suspected? But what happen when there is no threshold or guide value? Gap of ecotox. - tox. data / substances not regulated Only the investigation and occurrence indicators give the category of action ► How sensitive must be analytical methods for the monitoring of substances in GW ?

Simplified decision tree mixing option 1 and 2 Max RL < lowest TV (0.1µg/L by default) TV exceed or 0.1 µg/L exceed. No or ? Yes No Yes No GW transfer evidences ? > This scheme was applied to select the substances for regular monitoring in GW > Human health effects are use for the categorization > PNEC are used for the scoring > 21