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Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Fish: Exposure of rainbow trout to the test item gave LL50 values > 50 mg/L loading rate WAF (OECD 203 and EU Method C.1).

 

Aquatic invertebrates: Exposure of Daphnia magna to the test item gave EL50 values > 50 mg/L loading rate WAF (OECD 202 and EU Method C.2).

 

Algae: Exposure of Pseudokirchneriella subcapitata to the test item gave EL50 values > 50 mg/L loading rate WAF (OECD 201 and EU Method C.3).

 

Microorganisms: The effect of the test item on the respiration of activated sewage sludge gave a 3-Hour EC50 value > 1000 mg/L. The No Observed Effect Concentration (NOEC) after 3 hours exposure was 1000 mg/L (OECD 209).

Additional information

Fish

A key study was performed to assess the acute toxicity of the test item to rainbow trout (Oncorhynchus mykiss). The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals (1992) No 203, "Fish, Acute Toxicity Test" referenced as Method C.1 of Commission Regulation (EC) No. 440/2008.

Due to the low aqueous solubility and complex nature of the test item for the purposes of the test the test item was prepared as a Water Accommodated Fraction (WAF). A study to determine the general physico-chemical properties of the test item indicated the water solubility of the test item was less than 1.0 mg C/L. Given this it was considered appropriate to test up to a maximum loading rate of 50 mg/L to prevent overloading of the aqueous phase with undissolved test item. In accordance with the recommendations of REACH, the test was conducted according to the threshold approach recommended by ECHA. Using this approach, the lowest EL50 value from either the algal growth inhibition study or acute toxicity to Daphnia magna study is set as the threshold loading rate and a “Limit test” is conducted at this threshold loading rate. If no mortalities are observed this indicates that fish are not the most sensitive species and that the LL50 is greater than the threshold loading rate. Therefore, as the EL50 value obtained for both the Algal Growth Inhibition study and the Acute Toxicity to Daphnia magna study were greater than 50 mg/L loading rate WAF, the test was conducted at a single loading rate of 50 mg/L loading rate WAF to ensure that toxicity was not observed at this loading rate. Seven fish were exposed to a Water Accommodated Fraction (WAF) of the test item, at a single nominal loading rate of 50 mg/L for a period of 96 hours at a temperature of 14 °C to 15 ºC under semi-static test conditions. The number of mortalities and any sub-lethal effects of exposure in each test and control vessel were determined 3 and 6 hours after the start of exposure and then daily throughout the test until termination after 96 hours.

 

Total Organic Carbon (TOC) analysis of the 50 mg/L loading rate WAF fresh test preparations at 0 and 72 hours showed measured carbon concentrations of less than the control. TOC analysis of the 50 mg/L old test preparations at 24 and 96 hours showed measured carbon concentrations of less than the limit of quantification (LOQ) of the method employed, which was determined to be 1.0 mg/L, and 0.36 mg/L (control corrected value) respectively. Given that the toxicity cannot be attributed to a single component or a mixture of components, but to the test item as a whole, the results were based on nominal loading rates only.

 

Exposure of rainbow trout to the test item gave LL50 values of greater than 50 mg/L loading rate WAF. The No Observed Effect Loading Rate was 50 mg/L loading rate WAF. It was considered unnecessary and unrealistic to test at loading rates in excess of 50 mg/L.

Daphnia magna

A key study was performed to assess the acute toxicity of the test item to Daphnia magna.The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals (April 2004) No 202," Daphnia sp., Acute Immobilisation Test" referenced as Method C.2 of Commission Regulation (EC) No. 440/2008.

 

Due to the low aqueous solubility and complex nature of the test item for the purposes of the test the test item was prepared as a Water Accommodated Fraction (WAF). A study to determine the General Physico-chemical Properties of the test item indicated the water solubility of the test item was less than 1.0 mg C/L. Given this it was considered appropriate to test up to a maximum loading rate of 50 mg/L to prevent overloading of the aqueous phase with undissolved test item. Twenty daphnids (4 replicates of 5 animals) were exposed to Water Accommodated Fractions (WAFs) of the test item over a range of nominal loading rates of 5.0 and 50 mg/L for 48 hours at a temperature of 21 to 22 °C under static test conditions. The number of immobilized daphnia and any adverse reactions to exposure were recorded after 24 and 48 hours.

 

Total Organic Carbon analysis of the 5.0 and 50 mg/L loading rate WAF fresh test preparations at 0 hours showed measured carbon concentrations of 1.6 to 1.4 mg/L, respectively. Analysis of the 5.0 and 50 mg/L aged test preparations at 48 hours showed measured carbon concentrations of less than the limit of quantification (LOQ) of the method employed, which was determined to be 1.0 mg/L. Analysis of the control samples at 0 and 48 hours showed carbon concentrations of less than the LOQ. The dissolved test item may have been one or several components of the test item. Given that the toxicity cannot be attributed to a single component or a mixture of components, but to the test item as a whole, the results were based on nominal loading rates only. 

 

Exposure of Daphnia magna to the test item gave EL50 values of greater than 50 mg/L loading rate WAF. The No Observed Effect Loading Rate was 50 mg/L loading rate WAF. It was considered unnecessary and unrealistic to test at loading rates in excess of 50 mg/L.

Algae

A key study was performed to assess the effect of the test item on the growth of the green alga Pseudokirchneriella subcapitata. The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals (2006) No 201, "Freshwater Alga and Cyanobacteria, Growth Inhibition Test" referenced as Method C.3 of Commission Regulation (EC) 761/2009.

 

Due to the low aqueous solubility and complex nature of the test item for the purposes of the test the test item was prepared as a Water Accommodated Fraction (WAF). A study to determine the General Physico-Chemical Properties of the Test Item indicated the water solubility of the test item was less than 1.0 mg C/L. Given this it was considered appropriate to test up to a maximum loading rate of 50 mg/L to prevent overloading of the aqueous phase with undissolved test item. Following a preliminary range-finding test, Pseudokirchneriella subcapitata was exposed to a Water Accommodated Fraction (WAF) of the test item, at a single nominal loading rate of 50 mg/L (six replicate flasks) for 72 hours, under constant illumination and shaking at a temperature of 24 ± 1 °C. Samples of the algal populations were removed daily and cell concentrations determined for each control and treatment group, using a Coulter Multisizer Particle Counter.

 

Total Organic Carbon (TOC) analysis of the test preparations performed at 0 and 72 hours showed measured concentrations of 1.88 mg C/L at 0 hours and 1.24 mg C/L at 72 hours. Given that the toxicity cannot be attributed to a single component or a mixture of components but to the test item as a whole, the results were based on nominal loading rates only. 

 

Exposure of Pseudokirchneriella subcapitata to the test item gave EL50 values > 50 mg/L loading rate WAF. The No Observed Effect Loading Rate was 50 mg/L loading rate WAF. It was considered unnecessary and unrealistic to test at loading rates in excess of 50 mg/L.

Inhibition of sewage sludge micro-organisms

A key study 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)".

 

Activated sewage sludge was exposed to an aqueous dispersion of the test item at concentrations of 10, 100 and 1000 mg/L (3 replicates of the 1000 mg/L concentration) for a period of 3 hours at a measured temperature of 20 °C with the addition of a synthetic sewage as a respiratory substrate. The rate of respiration was determined after 3 hours contact time and compared to data for the control and a reference item, 3,5-dichlorophenol.

The effect of the test item on the respiration of activated sewage sludge gave a 3-Hour EC50 value of greater than 1000 mg/L. The No Observed Effect Concentration (NOEC) after 3 hours exposure was 1000 mg/L. It was considered unnecessary and unrealistic to test at concentrations in excess of 1000 mg/L. The reference item gave a 3-Hour EC50 value of 6.7 mg/L, 95% confidence limits 5.1 to 8.8 mg/L.