The T-value in the score for hazard refers to acute toxicity. Underlying data for B and T are from Fass. According to expert, paracetamol is not considered to be persistent based on data from Fass environmental information (Researcher at the Department of Environmental Science and Analytical Chemistry (ACES), Stockholm University (2019-11-06). The risk comes from the Report Goodpoint 2019.
Fass environmental information for Alvedon forte (paracetamol) from GlaxoSmithKline Consumer Healthcare AB (downloaded 2018-09-24).
Persistence: "Results of biological degradation: Inherent biodegradation = 99% in 5 days (OECD 302B, IUCLID data set). The substance is inherently biodegradable. The material is expected to be highly removed in wastewater treatment plants, 98% removal (Reference 9). This is supported by a measured biodegradation constant of 58–80 L g-1 d in a WWTP simulation test (Reference 6). Biodegradation constants greater than 10 are expected to result in greater than 90% biodegradation. Additionally, a DT50 of 3.1d and a DT90 of 10d was measured (Reference 8) using a water-sediment study (OECD 308) indicating a low potential for persistence. The phrase ‘Paracetamol is slowly degraded in the environment’ is thus chosen."
Bioaccumulation: Log Pow = 0.51 at pH 7 (OECD 107).
Acute toxicity: There is data for 3 trophic levels, lowest for algae (Scenedesmus subspicatus) 9 200 microg/L.
PEC/PNEC is based on sales data in Sweden in year 2014. PEC/PNEC = 0.196 which gives the risk low.
Studies from several Swedish wastewater treatment plants showed that paracetamol was reduced with up to 99%. Concentrations of paracetamol detected in a gradient from the inner city of Stockholm into the archipelago are up to 6.6 ng/L. Paracetamol has been found in surface water within Region Stockholm in 2018 at concentrations up to 200 ng/L.
Paracetamol has also been measured in drinking water in the Stockholm area at concentrations up to 15 ng/L (The report from IVL and drug analysis in Region Stockholm).
Comparative assessment of environmental risk when using diclofenac, naproxen, ibuprofen, ketoprofen, etoricoxib, celecoxib and paracetamol from a Swedish perspective (Report Goodpoint 2019). From an environmental risk point of view, exchanging diclofenac for any of the other investigated NSAIDs/analgesics is recommended. [...] Paracetamol is a very safe alternative from an environmental point of view. The other APIs are also considered to pose low environmental risk, but slightly increased for ketoprofen. The risk factors for ketoprofen, naproxen, ibuprofen, celecoxib, etoricoxib and paracetamol are not considered so great that an exchange with another substance is recommended. Environmental measurements as well as efficacy studies of both celecoxib and etoricoxib are required."
Author: Health and Medical Care Administration, Region Stockholm