Registration Dossier

Administrative data

activated sludge respiration inhibition testing
Data waiving:
study scientifically not necessary / other information available
Justification for data waiving:

Data source

Materials and methods

Results and discussion

Details on results:
The lowest endpoint for Zn to mircoorganisms was taken from the REACH dossier of Zn oxide (CAS 1314-13-2). In a key study, a NOEC of 100 µg Zn/L with respect to the nitrification rate was determined. In the dissolution/transformation test the maximum Zn concentration of three replicates/concentrations were 11, 28 and 300 µg/L at a loading rate of 1, 10 and 100 mg/L. Based on the comparison of the dissoluted/transformed Zn concentration and the NOEC, it can be concluded that the NOEC of the substance to microorganisms is above the loading rate of 10 mg/L.

Applicant's summary and conclusion