Section 8

Ecotoxicology

Laura Villamar, Alfonso Lostia,

Scientific officers, PRES Unit

TG IUCLID PESTICIDES meeting

21-22 April 2020

Mariana Pérez

Scientific officer, DATA Unit

OUTLINE of IUCLID Ecotoxicology session

Welcome!

Purpose of this session

OHT 45 - Toxicity to aquatic algae and cyanobacteria

OHT 46 - Toxicity to aquatic plants

OHT 53 – Toxicity to birds

Introduction to ED assessment and data collection

OHT 48-2 - Endocrine disrupter testing in aquatic vertebrates

OHT 75-3 - Endocrine disrupter mammalian screening – In vivo

‘As discussed at the weekly technical group meeting, the objective forthis session is to agree adaptations to OHTs which can be proposedto the OECD expert group by the end of April for inclusion in theOctober release of IUCLID (i.e. straight forward and non-controversialamendments).

Where the sub-group agrees a more thorough review of an OHT isrequired (i.e. deeper review and further discussion needed), it issufficient to identify these documents which a can be analyzed at a laterphase in the project and worked on in small group over the year andmay be submitted to the OECD expert group for the next revision in April2021.’

Objective

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OHT 45 – Toxicity to aquatic algae and cyanobacteria

Include the analytical confirmation of the dissolved test concentration

Update of species in the picklist: Aphanothece clathrate, Synechococcus leopoliensis, Pediastrum duplex, Nannochloropsis, Achnanthidium minutissimum and Nitzschia linearis (diatom)

Update guidelines: ASTM E 1218-04. Standard guide for conducting 96-h toxicity tests with microalgae, OCSPP 850.4500: Algal Toxicity, OCSPP 850.4550: Cyanobacteria (Anabaena flos-aquae) Toxicity

Include details about the used culturing apparatus

Add dose descriptors to the picklist

Ebc50 (percent reduction in biomass growth) and Erc50 (percent reduction in growth rate)

Include in the picklist of basis for effect: Average specific growth rate, area under the growth curve (biomass), mean values for cell density and yield

Update guidelines

ASTM E1913-04: Standard Guide for Conducting Static, Axenic, 14-Day Phytotoxicity Tests in Test Tubes with the Submersed Aquatic Macrophyte, Myriophyllum sibiricum Komarov

Maltby, L. et al. (2010), Aquatic Macrophyte Risk Assessment for Pesticides, Guidance from the AMRAP Workshop in Wageningen (NL), 14-16 January 2008

OCSPP 850.4400: Aquatic Plant Toxicity Test Using Lemna spp

OCSPP 850.4450: Aquatic Plants Field Study

Draft OECD guideline: Growth Inhibition Test for the Rooted, Emergent Aquatic Macrophyte, Glyceria maxima

Separate the field “Basis for effects” since it includes both, response variables (growth rate, yield) and measurement variable (frond number, shoot length).

OHT 46 – Toxicity to aquatic plants

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OHT 53 Toxicity to birds

Add term of “dose-response” in the test section

Modify the term “bolus” for “single dose” in the total exposure duration

Add dose descriptors for ECx (EC10, EC20)

Update guidelines

The repellency field might need to be eliminated, since it is not actually

evaluated as such

In the details on preparation and analysis of diet, there is a need to

implement a free text for “Analytical methods in feed”.

Is it required to make the endpoints more specific in OHT 45?

E.g. Effects on growth of green algae, Effects on growth of an additional algal species

Which descriptors should be added or considered for higher tier assessment in birds?

What are some of the additional modifications needed in the OHTs to ensure the proper data recording in IUCLID?

Points for discussion

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Background information Endocrine Disruptor

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EFSA has developed a template to report the ED assessment

An excel file has been developed to collect all relevant informationneeded to perform the ED assessment. The excel file is a tool tosystematically collect relevant data and to facilitate the EDassessment. It provides an overview of the entire dataset related toED assessment by reducing the need to go back to the singlestudies.

Type of information relevant for ED assessment

Studies

Short-term (e.g. 28-day, 90-day)

Long-term studies/carcinogenicity

Reproductive and developmental

Literature studies

Mechanistic studies

In vitro assays (e.gToxCast)

Endpoints

Endpoint specific for ED: about 200

Endpoints related to general toxicity (needed to properly evaluate ED-related endpoints)

Endpoints’ information

All effects observed: positive and negative

Doses: at which doses an effect was observed

Time: at which time-points an effect was observed

Severity and incidence of the effect

Etc.

Excel file

About 40 columns capturing information related to study design and results

Several rows depending on richness of the dataset (potentially up to thousands)

Each row reports information for one endpoint within a study. If there are 10 relevant

endpoints, the information is displayed over 10 rows.

Excel file: data-matrix

The information captured in the excel file is automatically re-organised tofacilitate the assessment.

First, a data-matrix is built which visually displays all relevant information. Inthe matrix, each row now represents all the endpoints within a study.

Excel file: lines of evidence table

The information captured in the excel file is automatically re-organised tofacilitate the assessment.

Second, a line of evidence table is built. This is used to support the WoE foradversity and endocrine activity based on the ECHA-EFSA Guidance on ED.

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Proposal: to keep the Excel file. Excel to be uploaded in IUCLID in regular basis.

WHAT ABOUT FUTURE?

Question 1: is it necessary to develop an OHT for reporting the ED assessment according to the ECHA/EFSA guidance?

Question 2: is there a way we can avoid duplication of the data (data might be already available in specific OHTs for mam tox/ ecotoxassessment)?

Addition of Endpoint:

amphibian Xenopus laevis, embryo: (sub)lethal effects

Addition and update of guidelines

e.g. OPPTS 850.1500, OECD GD 148, OECD TG 248 (Xenopus Eleutheroembryonic Thyroid Assay (XETA))

And studies protocols NOT validated YET at OECD level: RADAR, REACTIV, EASZY, JMASA

Addition of basis for effect: Larval survival, Larval length, Hatching success, Malformations (amphibians) and Transcriptional activity of cyp19a1b and Transcriptional activity of THbZIP

Addition of a field to revise the maintenance of concentrations in water

OHT 48-2 Endocrine disrupter testing in aquatic vertebrates

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Proposal:Further session aimed

for more in depth discussion

Addition and update of guidelines

Suggestions?

OHT 75-3 Endocrine disrupters mammalian screening

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Proposal:

Further session aimed for more in depth discussion