Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Differents studies were performed to assess the acute toxicity of the test item to three trophic levels; rainbow trout (Oncorhynchus mykiss),Daphnia magna and and algae (Pseudokirchneriella subcapitata). The methods followed were designed to be compatible with the appropriate OECD Guidelines for Testing of Chemicals.

Preliminary solubility work indicated that it was not possible to obtain a testable solution of the test item using traditional methods of preparation e.g. ultrasonication and high shear mixing. The test item was known to rapidly degrade in water. Given this, and in accordance with current regulatory guidance, the concentration of the degradation product was determined to confirm dosing. A preliminary media preparation trial indicated that a dissolved degradation product concentration of approximately 86 mg/L was obtained from a saturated solution method of preparation indicating this to be the limit of water solubility of the degradation product under test conditions.

In accordance with the recommendations of REACh, the acute fish test was conducted according to the threshold approach recommended by ECHA.  Using this approach the lowest EC50 value from either the Algal Growth Inhibition study or Acute Toxicity to Daphnia magna study is set as the threshold concentration and a “Limit test” is conducted at this threshold concentration. If no mortalities are observed this indicates that fish are not the most sensitive species and that the LC50 is greater than the threshold concentration.

The following endpoints were determined based on measured concentrations:

Acute fish LC50 >53 mg/L

Acute Daphnia EC50 > 37 mg/L

Algal inhibition ErC50 > 24 mg/L

In addition to the three aquatic studies a test was performed to assess the effect of the test item on the respiration of activated sewage sludge. The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals (2010) No. 209 "Activated Sludge, Respiration Inhibition Test (Carbon and Ammonium Oxidation)".

The effect of the test item on the respiration of activated sewage sludge provided the following results

3-hour EC50 value >1000 mg/L

3 -hour EC10 value >100 mg/L

Additional information