The Partnership for the Assessment of Risks from Chemicals (PARC) has published a new Concept Note on Suspect and Non-Target Screening (SS/NTS), developed within the Monitoring and Exposure work area, with contributions from the Innovative Methods team.

The document provides scientific support to the policy positioning of SS/NTS approaches, which are increasingly used in environmental monitoring, food safety and human biomonitoring, but whose integration into routine regulatory chemical risk assessment remains limited.

Chemical exposure in Europe is characterised by the presence of thousands of substances originating from industrial activities, agriculture and consumer products. These substances coexist as complex mixtures, vary over time and space, and interact along the environment–food–human continuum. As a result, a large part of the chemical exposure vector remains insufficiently characterised.

Current exposure, hazard and risk assessment frameworks rely largely on targeted analytical approaches, focusing on predefined substances and operating mainly within sectoral regulatory boundaries. While essential, these approaches are not sufficient to address the complexity of real-life exposure scenarios, nor the continuous emergence of new or previously unknown chemicals.

In this context, suspect and non-target screening approaches offer a complementary perspective, enabling a broader and more timely characterisation of chemical exposure relevant to human health and the environment.

What SS/NTS approaches can deliver for policy

SS/NTS are comprehensive chemical profiling approaches, typically based on high-resolution mass spectrometry, that allow the detection and, where possible, identification of suspected or unknown chemicals without prior knowledge of their presence. From a regulatory perspective, these methods fall within the category of screening tools and should be considered in complement to conventional targeted approaches.

Jean-Philippe Antignac, co-lead of the Innovative Methods activities within the Monitoring and Exposure work package, said:

Suspect and non-target screening approaches do not replace targeted analysis, but they offer a powerful complementary perspective by capturing real-life chemical mixtures and supporting early warning and prioritisation in chemical risk assessment.

When appropriately positioned, SS/NTS can support policy at different levels:

• By identifying chemicals present in real-life environmental, food and human samples, complementing and contributing to the compound prioritization of targeted monitoring programmes.

• By generating semi-quantitative exposure patterns that support risk prioritisation, trend analysis and early warning systems.

• By contributing to novel marker discovery, retrospective analyses and the identification of emerging substances of concern.

State of implementation and remaining challenges

Over the past fifteen years, SS/NTS approaches have been increasingly applied across Europe, particularly in environmental monitoring, food safety and human biomonitoring. Initiatives such as the NORMAN Network, EFSA ↗ activities and the European Human Biomonitoring Initiative (HBM4EU) have played a key role in advancing methodological development and harmonisation.

Despite this progress, routine implementation in regulatory contexts remains limited. Key challenges include the need for specialised analytical and bioinformatics expertise, limited inter-laboratory comparability, quality assurance and transparency issues, and ethical and communication considerations, particularly in human biomonitoring, where unexpected findings may arise.

PARC’s added value

The Concept Note highlights PARC’s ambition to build on existing scientific capacity and strengthen harmonisation across the environment, food and human biomonitoring domains, with a view to improving data comparability and policy relevance.

It formulates recommendations to support the gradual and fit-for-purpose integration of SS/NTS into chemical risk assessment, including harmonised performance criteria, reporting formats and confidence levels, strengthened laboratory networks, and improved interpretability of results in regulatory and forward-looking policy contexts. The document also highlights the potential of combining SS/NTS with complementary approaches such as effect-directed analysis (EDA) to better link chemical exposure with biological effects.

Supporting future chemical policies

The Concept Note concludes that SS/NTS approaches represent an important methodological evolution for chemical exposure assessment. They already provide valuable support for understanding real-life chemical mixtures, identifying overlooked or emerging substances, and informing prioritisation and early warning systems.

By translating complex scientific developments into a policy-relevant framework, PARC aims to support regulators and public authorities in using SS/NTS in a scientifically sound way for chemical risk assessment and management.