Etonogestrel

Detailed information

Fass environmental information

Fass environmental information for Nexplanon (etonogestrel) (downloaded 2021-09-21).

Hazard

Persistence: "Sediment Transformation (OECD 308) (Ref. XII): DT₅₀ in water: 10–11 days; DT₅₀ in sediment: 35–70 days; DT₅₀ in total system: 9.2–50 days. [...] Etonogestrel has a DT₅₀ for the total system of ≤120 days. Thus, the phrase “Etonogestrel is slowly degraded in the environment” is chosen."

Bioaccumulation: "Log K_ow = 3.5. Bioaccumulation (OECD 305): Flow through study with Bluegill sunfish (Lepomis macrochirus) Lipid normalized kinetic BCF = 128."

Chronic toxicity: There is NOEC for 3 trophic levels, lowest NOEC 183 days for fish (Oryzias latipes) 2.7 nanog/L.

Risk

PEC/PNEC is based on sales data in Sweden in year 2018. PEC/PNEC = 2.8 which gives the risk moderate.

Pharmaceuticals residues in the aquatic environment in Sweden

Etonogestrel has been tested but has been below the quantification limit (LOQ). Etonogestrel is the active metabolite of desogestrel.

Report from Goodpoint 2017

Etonogestrel has approximately the same ability to bind to the androgen receptor in fish such as levonorgestrel. A substance's ability to activate the androgen receptor in fish is believed to contribute to increased risk of environmental impact. Etonogestrel also binds to SHBG (Sex Hormone Binding Globulin). Binding to SHBG is believed to contribute to increased bioconcentration (and thus potency) in fish. Based on this, it can be assumed that there is a risk associated with the use of etonogestrel/desogestrel and that these substances appear additive with other androgenic gestagens in the environment.