Registration Dossier

Ecotoxicological information

Short-term toxicity to fish

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Two acute toxicity studies with fish are available. In the key study (Geiger, 1985) with Pimephales promelas, where the LC50 (96 h) was  484 mg/L (EPA OPP 72-1) based on measured concentrations under flow through conditions.  

The results were confirmed in the supporting study (Ewell, 1986) with Pimephales promelas the LC50 (96 h) was >100 mg/L. The test protocol was similar to OECD 203.

Key value for chemical safety assessment

LC50 for freshwater fish:
484 mg/L

Additional information

Two acute toxicity studies with fish are available both indicating an LC50 > 100 mg/L. The key study (Geiger, 1985) is a flow-through study, where a decrease of test concentration is prevented and there the LC50 is also >> 100 mg/L (484 mg/L). In the supporting study (Ewell, 1986) this was a static 96 hour study performed according to a protocol similar to OECD 203. No analytics were included. In view of the high water solubility it is expected that measured concentrations would not deviate significantly from nominal values. However, in the recently performed algae study (Migchielsen 2010), the test concentrations decreased significantly during the 96 hour study period. Therefore it cannot be excluded that a similar phenomenon would have been seen in the static study of Ewell (1986) if measured. Based on these considerations the absence of measured data is considered not to influence the derivation of the LC50 in this supporting study.