The T-value in the score for hazard refers to acute toxicity. Underlying data for P, B, T and risk are from Fass.
Fass environmental information for Ergenyl Retard (valproic acid) (downloaded 2018-11-15).
Persistence according to "Ready biodegradability: Test showed 48 % degradation in 28 days (OECD 301). Valproic acid fails to pass the criteria for ready biodegradability. The phrase "Valproic acid is potentially persistent" is thus chosen."
Bioaccumulation: Log Kow = 2.60 at pH 7 (OECD 107).
Acute toxicity: There are data for 3 trophic levels, lowest for fish (Danio rerio) 66 000 microg/L.
PEC/PNEC is based on sales data in Sweden in year 2016. PEC/PNEC = 0.004 which gives the risk insignificant.
Author: Department of Strategic Careers, Stockholm County Council.