Pharmaceuticals
Detected at nanogram concentrations in rivers and, at lower levels, in drinking water. The established environmental effects are real; the drinking water health significance at measured concentrations is not.
Key facts
- Contaminant group
- Emerging contaminant
- European Union — guideline
- Watch list monitoringSeveral pharmaceuticals including diclofenac and selected antibiotics are on the surface water watch list. No drinking water limits are set.
- World Health Organization — guideline
- No guideline valuesWHO concluded that concentrations in drinking water are typically more than a thousandfold below the minimum therapeutic dose.
Where it comes from
- Human excretion of prescribed and over-the-counter medicines, passing through wastewater treatment largely intact
- Disposal of unused medicines to drains
- Veterinary medicines from livestock and aquaculture
- Manufacturing discharge, which produces far higher local concentrations
How it behaves in water
Conventional wastewater treatment was designed for organic load and removes pharmaceuticals only partially and inconsistently. Removal ranges from over 90% for readily biodegradable compounds such as ibuprofen to essentially none for carbamazepine, which is why carbamazepine is used as a wastewater tracer.
How it is measured
Nanograms per litre by LC-MS/MS. Detection capability has improved by orders of magnitude, so "increasingly detected" often means increasingly detectable rather than increasingly present.
Regulatory position
| Jurisdiction | Value | Status | Notes |
|---|---|---|---|
| European Union | Watch list monitoring | guideline | Several pharmaceuticals including diclofenac and selected antibiotics are on the surface water watch list. No drinking water limits are set. |
| World Health Organization | No guideline values | guideline | WHO concluded that concentrations in drinking water are typically more than a thousandfold below the minimum therapeutic dose. |
Table sources
- World Health Organization — Guidelines for Drinking-water Quality. Public but restricted · CC BY-NC-SA 3.0 IGO
- European Commission — Drinking Water Directive (EU) 2020/2184 and reporting. Open — attribution required · European Commission reuse policy (Decision 2011/833/EU)
- Drinking Water Inspectorate — Drinking water quality in England and Wales. Open — attribution required · Open Government Licence v3.0
- United States Environmental Protection Agency — Safe Drinking Water Information System. Open · US Government work — public domain
Health context
Concentrations found in treated drinking water are typically several orders of magnitude below any therapeutic dose. The better-established concerns are ecological: hormone disruption in fish from synthetic oestrogens, and the near-extinction of South Asian vultures from diclofenac in livestock carcasses.
What removes it
| Row | Effective | Not reliably effective |
|---|---|---|
| 1 | Ozone combined with biological activated carbon | Boiling |
| 2 | Granular activated carbon | Conventional coagulation and filtration alone |
| 3 | Reverse osmosis and nanofiltration | Chlorination, which transforms rather than removes and can produce by-products |
| 4 | Advanced oxidation | — |
Related intelligence
Sources
- World Health Organization — Guidelines for Drinking-water Quality. Public but restricted · CC BY-NC-SA 3.0 IGO
- Peer-reviewed scientific literature — Open-access hydrology, water chemistry and water use research. Public but restricted · Publisher terms — public access, reuse not clearly granted