An initial set of criteria was then produced, including such aspects as whether a substance is of concern to human health, whether there is evidence of human and/or environmental exposure at EU level and whether there are open policy questions. The financial and technical feasibility of monitoring the substances was also a criterion.

Substances proposed at both national and EU level were then systematically assessed against these criteria, based on information provided from both EU and national levels. This first prioritisation exercise resulted in the nine substance groupings that have been the focus of HBM4EU activities in 2017 and 2018.

The first list of HBM4EU priority substances includes:

• Aniline family
• Bisphenols
• Cadmium and chromium VI
• Chemical mixtures
• Emerging substances
• Flame retardants
• PAHs
• Per-/poly-fluorinated compounds
• Phthalates and Hexamoll® DINCH

The consortium compiled information on substance classification, policy-related research questions and research objectives for each substance, with the results captured in scoping documents for the first list of priority substances. These scoping documents formed the basis for the development of activities for inclusion in the annual action plans for HBM4EU.

A second round of prioritisation was conducted from 2017 to 2018. The consortium built on the experience gained with the first prioritisation exercise, refined the approach to increase transparency and included stakeholders.

The second list of HBM4EU priority substances includes:

• Acrylamide
• Aprotic solvents
• Arsenic
• Diisocyanates
• Lead
• Mercury
• Mycotoxins
• Pesticides
• Benzophenones

Scoping documents for the substances on the second list are currently in production.

A third round of prioritisation is foreseen for 2019 to 2020. The aim of this third round will be to identify priorities for research under a future European human biomonitoring initiative post 2021.