Kommersiellt obunden läkemedelsinformation riktad till läkare och sjukvårdspersonal

Metronidazole

Hazard 4 P 3 B 0 T 1 Risk See below

Information

The T-value in PBT refers to acute toxicity.

Pharmaceutial residues in the aquatic environment

There is a risk of selecting resistant bacteria with the concentrations measured in Swedish wastewater treatment plants. However, the estimate of selective concentration is very uncertain for metronidazole and measurements have not been taken in recent years. Metronidazole has previously been found in purified wastewater and surface water in Stockholm County (2005–2012).

Fass environmental information

The risk classification insignificant, according to Fass.se, is based on total sold amount (kg) of the substance in Sweden during the year 2014 and the toxicity of the substance.

Report Goodpoint 2018

Comparative assessment of environmental risk and risk of resistance selection in human use of ivermectin, metronidazole, lymecycline and azelaic acid in Sweden (Report Goodpoint 2018). The risk is clearly highest for lymecycline based on measured concentrations of tetracycline in uncleaned waste water that exceeds experimental established selective levels for antibiotic resistance in bacteria. A similar but lower risk profile exists for metronidazole based on total use but with significantly lower empirical support for the efficacy The topical use of metronidazole results in a negligible risk of resistance selection in waste water treatment plants. The risk of effects of human use of ivermectin is also low, given an expected contribution to exposure in aquatic environments at subnanogram levels, and a majority of efficacy studies that show significantly higher levels of efficacy. Since there is (at least) a study that reports effects at 1 pg/L, however, one can not completely rule out risk. For azelaic acid there is nothing that indicates an environmental hazard.

References

  1. Goodpoint. Prioritering av läkemedel med miljörisk inom SLL. Stockholm: Goodpoint; 2016. Rapport LS 2016–0634.
  2. Khalil WK, Mahmoud MA, Zahran MM, Mahrous KF. A sub-acute study of metronidazole toxicity assessed in Egyptian Tilapia zillii. J Appl Toxicol. 2007;27:380-90.
  3. Bengtsson-Palme J, Larsson DG. Concentrations of antibiotics predicted to select for resistant bacteria: Proposed limits for environmental regulation. Environ Int. 2016;86:140-9.
  4. Fick J, Lindberg RH, Tysklind M, Larsson DG. Predicted critical environmental concentrations for 500 pharmaceuticals. Regul Toxicol Pharmacol. 2010;58:516-23.
  5. Sammanställning av läkemedelsprovtagningar - Bearbetning av regional försäljningsstatistik av läkemedel samt datamaterial från Stockholms läns landstings mätprogram för läkemedelssubstanser i vattenmiljön, 2005-2012. Trossa AB På uppdrag av Stockholms läns landsting. 2014.
  6. Fass.se för vårdpersonal
  7. Goodpoint. Jämförande bedömning av miljörisk och risk för resistensselektion vid human användning av ivermektin, metronidazol, lymecyklin och azelinsyra. Stockholm: Goodpoint; 2018.

Author: The Pharmaceutical unit of Region Stockholm