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Priority Substance
A substance listed in Annex I of the EQSD that poses significant EU-wide risk to aquatic environments and requires harmonised EQS.
Substances identified as posing a significant risk at EU level to or via the aquatic environment. Determined through risk assessment at EU level. Listed in Annex I of Directive 2008/105/EC (as amended). All Member States must monitor these substances and meet the associated EQS values in their water bodies. Currently 70 substances or groups are listed as priority substances under Directive (EU) 2026/805.
Legal reference
Directive 2008/105/EC Art 2, Directive (EU) 2026/805 Annex VI