Carbamazepine
Summary
Persistence. Carbamazepine is very persistent.
Bioaccumulation. Carbamazepine has low potential for bioaccumulation.
Toxicity. Carbamazepine has high chronic toxicity.
Risk. The use of carbamazepine (sales data Sweden 2024) has been considered to result in low environmental risk.
This summary information comes from Fass, except for the assessment of persistence, which is based on the report from Goodpoint.. The information on bioaccumulation and environmental risk is also supported by the report from Goodpoint.
Carbamazepine is included in European legislation. It is listed under the Priority Substances Directive for surface waters (2008/105/EC), the Groundwater Directive (2006/118/EC) with established threshold values.
Detailed information
Fass environmental information
Fass environmental information Tegretol (carbamazepine) from Novartis (retrieved on 2026-07-06).
Excretion (metabolism)
"After administration of a single oral dose of 400 mg carbamazepine, 72% is excreted in the urine and 28% in the faeces. In the urine, about 2% of the dose is recovered as unchanged drug and about 1% as the pharmacologically active 10,11-epoxide metabolite."
Hazard
Persistence: Carbamazepine is not readily biodegradable, as no degradation was observed after 28 days in an OECD 301E test. In environmental simulation studies (OECD 308), the half-life in the total system was measured at 328 days. Based on these results, carbamazepine is classified as potentially persistent in the environment, since its half-life exceeds 120 days.
Bioaccumulation: Log Kow = 1.51–1.58 (OECD107).
Toxicity: There are data for 3 trophic levels, most sensitive crustacean NOEC 25 microg/L.
Risk
PEC/PNEC is based on sales data in Sweden in year 2024.
PEC = 0.503839 microg/L.
PNEC = Lowest NOEC, 25 microg/L/10 (Assessment Factor (AF) for 3 chronic studies) = 2.5 microg/L.
PEC/PNEC = 0.2 which gives the risk low.
Report from Goodpoint
Carbamazepine is very persistent in the environment, but has a low potential for biooaccumulation. There is very good knowledge about the occurrence of water in Sweden. The reports that claim low-level effects have significant deficiencies. Low risk of environmental impact out of credible data.
Pharmaceuticals residues in the aquatic environment in Region Stockholm and in other parts of Sweden
Carbamazepine has been detected in treated wastewater, surface water and drinking water in Region Stockholm.
Priority Substances Directive, Groundwater Directive and indicator in the Urban Wastewater Treatment Directive
Carbamazepine is included in European legislation. It is listed under the Priority Substances Directive for surface waters (2008/105/EC), the Groundwater Directive (2006/118/EC) with established threshold values.
Carbamazepine in caddisfly larvae
Carbamazepine has been detected in caddisfly larvae.
References
- Fass.se för vårdpersonal.
- Goodpoint. Prioritering av läkemedel med miljörisk inom SLL. Stockholm: Goodpoint; 2016. Rapport LS 2016–0634.
- Provtagningar av läkemedelsrester i vatten, sediment och fisk för Region Stockholm.
- IVL Swedish Environmental Research Institute Ltd. Fick J, Lindberg RH, Kaj L, Brorström-Lundén E. Results from the Swedish National Screening Programme 2010. Subreport 3, B 2014 Pharmaceuticals.
- IVL Swedish Environmental Research Institute Ltd Fick J, Lindberg RH, Fång J, Magnér J, Kaj L, Brorström-Lundén E. Screening 2014. Analysis of pharmaceuticals and hormones in samples from WWTPs and receiving waters. Rapport C 135.
- DIRECTIVE 2008/105/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL.
- DIRECTIVE 2006/118/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL.
- Richmond EK, Rosi EJ, et al. A diverse suite of pharmaceuticals contaminates stream and riparian food webs. Nat Commun. 2018 Nov 6;9(1):4491. doi: 10.1038/s41467-018-06822-w.
Author: Health and Medical Care Administration, Region Stockholm