Registration Dossier

Ecotoxicological information

Toxicity to microorganisms

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

The inhibition of the degradation activity of activated sludge is not anticipated when introduced in appropriately low concentrations.

Key value for chemical safety assessment

Additional information

In a short-term respiration test using industrial sludge (BASF AG, 1983) an EC20 of > 1995 mg/L and a NOEC of 750 mg/L was determined. Additionally, in a Pseudomonas putida test an EC10 of 33 mg/L was determined (BASF AG, 1989). According to RIP 3.2 chp R10.4.2 short-term respiration tests using industrial sludge can not be used to derive a PNEC for domestic sewage treatment plants.

It is commonly assumed that single species tests like the Pseudomonas test (DIN 38412, part 8) are more sensitive than tests using activated sludge (OECD 209). The deduction of the PNEC for microorganisms also considers this by assuming a lower assessment factor for Pseudomonas tests compared to short-term respiration tests. Since there is a pH-effect on Pseudomonas putida, the PNEC assessment is performed based on neutralized test solutions (17h EC10 > 500 mg/L).