No. 59

E1 (Estrone)

Estrone (E1)

CAS: 53-16-7Category: PharmaceuticalsDirective: EU 2026/805 Annex VI

Compliance target22 December 2039

Environmental Quality Standards

Water EQS

Values in μg/L (micrograms per litre)

AA-EQS — Inland waters	3.60e-4 μg/L
AA-EQS — Coastal & transitional	1.80e-5 μg/L
MAC-EQS — Inland waters	nd
MAC-EQS — Coastal & transitional	nd

Notes

Estrogenic substance. Effect-based monitoring mandatory for ≥2 years from 1 Jan 2030 (Art 8a(3)).

Effect-based monitoring required

Art 8a(3) of Directive (EU) 2026/805: Member States must apply effect-based monitoring methods for estrogenic substances (EE2, E2, E1) for at least 2 years from 1 January 2030.

Good chemical status target

22 December 2039

Monitoring guidance

Standard annual monitoring applies.

External resources

PubChem eChemPortal (ECHA/OECD)

Structure, physicochemical properties, and EU regulatory data

Data source

EQS values from Directive (EU) 2026/805 Annex VI.

Last verified: June 2026