|
Monitoring of Haloacetic Acids (HAAs) in the EU
in accordance with the Drinking Water Directive 2020/2184
Date: 5 December 2025
Prepared by: Maciej Jaworski, Spectroscopy Techniques Expert, Gekko Photonics
|
|
From 12 January 2026, monitoring of haloacetic acids (HAAs) in drinking water will become mandatory in all European Union countries.
This is one of the most significant updates to European water quality requirements in recent years.
|
What are Haloacetic Acids (HAAs)?
Haloacetic acids are a group of organic compounds formed as disinfection by-products (DBPs) in chlorinated water.
HAAs are chemically stable, highly soluble in water, and tend to accumulate. Long-term exposure.
|
|
HAA5 and HAA9 — what is the difference?
HAA5 (mandatory monitoring)
- monochloroacetic acid (MCA)
- monobromoacetic acid (MBA)
- dichloroacetic acid (DCA)
- dibromoacetic acid (DBA)
- trichloroacetic acid (TCA)
Directive Limit: 60 µg/L
HAA9 (broader research group)
- bromochloroacetic acid (BCA)
- bromodichloroacetic acid (BDCA)
- chlorodibromoacetic acid (CDBA)
- tribromoacetic acid (TBA)
These four compounds are not currently regulated, but literature suggests they may be more toxic than HAA5.
|
|
What exactly does Directive 2020/2184 introduce?
By 12 January 2026, each EU member state must ensure that drinking water complies with the new limits for disinfection by-products.
- Maximum HAA5 concentration: 60 µg/L
- Monitoring obligation wherever chlorination disinfection is applied
- Requirement to use reliable analytical methods ensuring result reproducibility
|
|
Why are HAAs considered a health hazard?
HAAs remain in water after disinfection and can exhibit toxic effects.
Key risks:
- potential carcinogenic effects,
- DNA damage and oxidative stress,
- mitochondrial and liver function impairment,
- neurotoxicity,
- endocrine and metabolic effects.
Exposure pathways:
- consumption of chlorinated water,
- ingestion of swimming pool water,
- food washed or cooked in chlorinated water.
|
|
How will standardizing HAA monitoring improve health protection in the EU?
Climate change promotes increased microorganism growth, necessitating more frequent disinfection.
Benefits of a unified monitoring system:
- early detection of exceedances,
- adjustment of treatment technologies,
- increased consumer safety,
- data comparability across the EU.
|
|
