Improved endocrine disruptor hazard assessment will protect human and environmental health

17 Jul 2024

Results from a ground-breaking European research project have strengthened collaborations between the toxicology and ecotoxicology research of endocrine disrupting chemicals (EDCs), promoting sustainable test methods for better protection of human and environmental health for future generations.

Launched in January 2019, the EU Horizon 2020-funded project, ERGO (EndocRine Guideline Optimisation) aimed to improve the hazard assessment of EDCs for the protection of human health and the environment. They wanted to break down the wall that existed between the different research fields that investigate effects of EDCs in different vertebrate classes and the different data used for regulation of EDCs for human health and the environment. ERGO used the well-conserved thyroid hormone system to demonstrate that it’s feasible to extrapolate effects of EDCs across the vertebrate classes. An adverse effect observed in a fish or amphibian used for environmental assessment of EDCs, should also raise concern for an adverse effect in rodents used for human health assessment of EDCs, for example.

ERGO tackled some of the gaps in existing standardised test methods used for screening and testing of EDCs according to different European Union (EU) legislations. Current testing tools don’t always appropriately identify the effects, particularly effects related to certain less studied or newly emerging EDCs. Regulatory procedures for identification and assessment of EDCs are often separated for human health and the environment. This means that useful data from non-mammalian vertebrate research tests (ecotoxicology) have so far been disregarded in human health research and EDC hazard assessment (toxicology). ERGO has developed new and improved testing methods to better protect human and environmental health against the hazards of EDCs.

Key achievements of ERGO include:

  • Investigating, developing, and pre-validating biomarkers and endpoints for thyroid hormone system disruption (THSD) in fish and bringing them into validation in the Organisation for Economic Co-operation and Development (OECD).
  • Investigating and developing new endpoints for THSD in amphibians.
  • Investigating and developing new in vitro assays for thyroid hormone system activity of chemicals and preparing them for OECD validation.
  • Investigating effects and new endpoints of thyroid hormone system disrupting chemicals in mammals.
  • Developing Adverse Outcome Pathways (AOPs) to the level of OECD endorsement as supporting tools for the endpoints/biomarker development in fish.
  • Development of AOP networks to facilitate extrapolation of thyroid hormone system disrupting effects across mammals, fish, and amphibians.
  • Interacting with stakeholders at the global (OECD), European (European Commission, European Food Safety Authority (EFSA), European Chemicals Agency (ECHA) and national environmental protection agencies (EPAs)) levels to discuss and promote the better use of data between human health and environmental health assessment of EDCs.
  • More than 40 peer-reviewed scientific publications and endorsed AOPs.
  • Diminishing the gap between approaches to endocrine disruptor research of human health toxicologists and environmental toxicologists through collaboration with fellow EURION Cluster projects on topics like THSD and developmental neurotoxicity.

The ERGO website (ergo-project.eu) showcases the project’s results and innovative outputs, including its publications, deliverables, policy briefs, and partner contact details, giving stakeholders and partners the opportunity to explore further opportunities to exploit and use the outputs.

Now that ERGO has closed, partners are ensuring that its legacy continues beyond the project, specifically through their involvement in new projects and ongoing initiatives that will progress the research developed within ERGO. Some examples include CELSPACCeHoSPARCNexEDENDOMIX and PEPPER. ERGO partners are also members of several international expert, advisory, reference, and working groups on endocrine disruptor research and regulation and will continue to communicate the cross-vertebrate class testing approach to the OECD as well as the national and international entities involved in the OECD Test Guideline Work Programme (TGP). However, at ERGO’s recent grand finale interactive workshop in Brussels, partners had the following key messages for policymakers and regulators:

  • Support research in less-studied endocrine axes to protect human health and environmental species against EDCs targeting non-EAST (estrogen, androgen, steroidogenesis, thyroid) endocrine axes e.g., the adrenal axis, retinoid axis and somatotropic axis and as a whole group – the endocrine axes that are specific for the invertebrate classes of animals.
  • Support breaking down the wall between human health, environmental testing, and regulation of EDs to accomplish the One Health vision in Europe. ERGO and other projects are providing increasing evidence that it’s feasible to extrapolate effects of EDs across the vertebrate classes.
  • Support the validation of new approach methods (NAMs) to facilitate implementation and use in different relevant regulatory frameworks, including financial support to support the paradigm shift to NAM-based regulation and reducing protected vertebrate testing.

Henrik Holbech, ERGO Coordinator from University of Southern Denmark highlighted the impact of the project:

“In 2019, 15 partners from eight countries came together to break down the wall between the different research and regulatory fields of toxicology and ecotoxicology that are investigating the adverse effects of endocrine disruptors (EDs) in different vertebrate classes. We wanted to demonstrate that it’s feasible to extrapolate effects of EDs across the vertebrate classes. I think it’s fair to say that after 5.5 productive years we have made quite a few substantial holes in that wall! The One Health approach is more highly recognised today and being incorporated into several EU strategies. I’m proud ERGO has contributed to this and is helping to understand and tackle the problems facing human and environmental health”.

For more information on ERGO and to access key results and resources please visit ergo-project.eu and also download the final project newsletter.