The T-value in the score for hazard refers to acute toxicity for the structural analogue ketotifen. The medicine is now withdrawn from use in Sweden (2013-01-31). The data on hazard and risk are based on previous environmental information on Fass.se.
Fass environmental information for Sandomigrin (pizotifen) (downloaded 2011-05-06).
Persistence: "5.0 % (29d, 20-24°C, OECD301B) not readily degradable."
Bioaccumulation: "Partition Coefficient log P 4.7 (calculated, Ertl et al., 2003). Log D 3.0 (pH 7, calculated using the Novartis internal Cheminformatics InSilico Profiling Tool, Novartis Institute of Biomedical Research, based on pKa and logP values). The phrase "Potential to bioaccumulate in aquatic organisms" is used due to the fact that calculated log P and log D values are ≥ 3."
Acute toxicity: There are data for 3 trophic levels for the structural analogue ketotifen, lowest NOEC for green algae (Desmodesmus subspicatus) 240 microg/L.
PEC/PNEC is based on sales data in Sweden in a year however, unclear which. PEC/PNEC = 0,00000178 which usually gives the risk insignificant. "However, as this study is a read-across from the structural analogue ketotifen, the phrase "Risk of environmental impact cannot be excluded, however some ecotoxicity data are available" is used."
Analyzes of pharmaceuticals in the aquatic environment nationally and in Stockholm County. At the latest national screening 2014, pizotifen has been found in treated wastewater (up to 1.4 ng/L) and surface water (up to 1.9 ng/L). The report also presents results from regional screening programs. In a previous report (2010), results from biota samples (perch) are reported with concentrations up to 4.5 microg/kg.
Pizotifen has been among the pharmaceuticals analyzed in Stockholm County during the last five-year period (2012-2016) and in measurements in 2017, but has not been detected.
Author: The Pharmaceutical unit of Region Stockholm