Effect-based methods and effect-based trigger values for estrogenicity monitoring in surface water: an...

Area of Science:

• Environmental Chemistry
• Ecotoxicology
• Water Quality Assessment

Background:

• European Water Framework Directive (WFD) considers effect-based methods (EBMs) for evaluating estrogenic substances.
• Estrogenic hormones and endocrine-disrupting chemicals (EDCs) pose risks to aquatic ecosystems.
• Assessing cumulative risks from chemical mixtures requires robust monitoring tools.

Purpose of the Study:

• To assess estrogenic EBMs and effect-based trigger (EBT) values for WFD implementation.
• To compare three EBT derivation options: linking to environmental quality standards (EQS), correlating in vitro/in vivo data, and averaging bioassay values.
• To evaluate the harmonisation and application of EBMs for managing estrogenic risks.

Main Methods:

• An interlaboratory study involving fourteen laboratories using EBMs on Northern-Italian surface water samples.
• Chemical analysis performed by four laboratories to identify specific estrogenic compounds and EDCs.
• Comparison of EBM results with chemical data and risk quotients (RQ) under different EBT derivation options.

Main Results:

• Chemical analysis revealed cumulative estrogenic risk in several samples, driven by estrone and bisphenol A.
• All EBMs detected estrogenic activity, with varying specificity towards hormones versus non-hormonal EDCs.
• EBT option 1 (linking to EQS) showed the highest concordance with chemical results and was most protective, while options 2 and 3 showed reduced risk quotients.

Conclusions:

• EBMs are valuable tools for detecting estrogenic activity and cumulative risks, even when individual chemical concentrations do not exceed EQS.
• Harmonisation of EBMs, including data evaluation, is crucial for addressing complex chemical mixtures.
• Integrating EBMs with conventional monitoring enhances protection against combined risks from estrogenic hormones and EDCs under the WFD.