The T-value in the score for hazard refers to chronic toxicity. Underlying data for P and B are from Fass. T comes from Fass environmental information for Naprosyn Entero. Risk comes from Report Goodpoint 2019.
Below is Hazard and Risk from Fass environmental information for Naprosyn Entero from Pharmanovia (downloaded 2019-11-06).
Persistence: "Naproxen is not readily biodegradable, however, it is inherently biodegradable and actual, measured elimination rates in various sewage works range from 0% to >99%, with a median of approximately 67%. Moreover, naproxen in surface waters is short-lived, due to biodegradation and photolysis in superficial layers (which is not included in the above PEC calculation). A surface water half-life in late summer in Switzerland at ~47° N was determined at 14 days. Hence, naproxen is rapidly degraded in sewage works and surface waters and is nonpersistent. [...] Naproxen is slowly degraded in the environment."
Bioaccumulation: "logD values below 1.1 at pH 6.5–7.4."
Toxicity: There are data for 3 trophic levels, most sensitive crustacean NOEC (Ceriodaphnia dubia) NOEC = 32 microg/L.
PEC/PNEC is based on sales data in Sweden in year 2010. PEC/PNEC = 0.92 which gives the risk low.
Fass environmental information for naproxen from Vimovo (esomeprazole, naproxen) from AstraZeneca (downloaded 2019-11-06).
Persistence: "Naproxen is classified as not readily biodegradable; however, results show that after a lag phase in an OECD 301B and OECD 301F (Refs. 32, 35) naproxen undergoes almost complete primary biodegradation in the presence of sewage sludge. Naproxen was also rapidly degraded in aquatic sediments in an OECD 308 preliminary test (up to 40% mineralisation after 14 days, Ref. 33) but in comparison was relatively stable in water in an OECD 309 test (Ref. 31). Overall the weight of evidence suggests that the presence of sludge and sediment plays an important role in the biotransformation of naproxen in the environment, and the phrase ‘Naproxen is slowly degraded in the environment’ reasonably reflects the available data."
Bioaccumulation: "BCF = 22–28 L/Kg after 14 days uptake."
Toxicity: here are data for 3 trophic levels, most sensitive crustacean (Daphnia magna) "21 day NOEC (survival, reproduction, growth)" = 150 microg/L.
PEC/PNEC is based on sales data in Sweden in year 2016. PEC/PNEC = 0.24 which gives the risk low.
Analyzes of pharmaceuticals in the aquatic environment in Region Stockholm. Naproxen has been detected in treated wastewater and surface water in Region Stockholm during 2012–2016. Naproxen has also been detected in treated wastewater at measurements 2017.
Large margin in Sweden between concentrations in the environment and the concentration that affects the environment.
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, the exchange of diclofenac is recommended for any of the other investigated NSAIDs/analgesics. [...] Paracetamol is a very safe alternative from an environmental point of view. The others 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