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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 of greater than 1.2 mg/L loading rate WAF. The No Observed Effect Loading Rate was 1.2 mg/L loading rate WAF (OECD 203 and EU Method C.1).

 

Aquatic invertebrates: Exposure of Daphnia magna to the test item gave an EL50 (48h) value of 19 mg/L loading rate WAF. The No Observed Effect Loading Rate (NOELR) was 6.25 mg/L loading rate WAF and the Lowest Observed Effect Loading Rate (LOELR) was reported as 12.5 mg/L loading rate WAF (OECD 202 and EU Method C.2).

Algae:Based on growth rate, exposure of Pseudokirchneriella subcapitata to the test item gave an EL50 (72h) value of 1.8 mg/L loading rate WAF, the No Observed Effect Loading Rate (NOELR) was reported as 0.625 mg/L and the Lowest Observed Effect Loading Rate (LOELR) was determined to be 1.25 mg/L. Based on yield, exposure of Pseudokirchneriella subcapitata to the test item gave an EL50 (72h) value of 1.2 mg/L loading rate WAF, the No Observed Effect Loading Rate (NOELR) was reported as 0.625 mg/L and the Lowest Observed Effect Loading Rate (LOELR) was determined to be 1.25 mg/L(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 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). In accordance with the recommendations of REACH, the test was conducted according to the threshold approach recommended by ECHA. Using this approach, the lowest median effect loading rate (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 median lethal loading rate (LL50) is greater than the threshold loading rate. The EyL50 value obtained from the Algal Growth Inhibition study was the lower of these two EL50 values and hence the test was conducted at a single loading rate of 1.2 mg/L. Seven fish were exposed to a Water Accommodated Fraction (WAF) of the test item, at a single nominal loading rate of 1.2 mg/L for a period of 96 hours at a temperature of 15 °C to 16 °C under semi-static test conditions. The number of mortalities and any sub-lethal effects of exposure in each test and control vessel were determined at 1, 3 and 6 hours after the start of exposure and then daily throughout the test until termination after 96 hours.

 

Samples of the control and 1.2 mg/l loading rate WAF were taken at 0 and 72 hours (fresh media) and 24 and 96 hours (old media) for Total Organic Carbon (TOC) analysis. Given the background level of carbon in the control vessels and also the low level of carbon in the test vessels, it was considered that all the results were around the limit of quantification of the analytical method. 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 1.2 mg/L loading rate WAF. The No Observed Effect Loading Rate was 1.2 mg/L loading rate WAF.

Aquatic invertebrates

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 medium was prepared as a Water Accommodated Fraction (WAF). Following a preliminary range finding test and initial experiment, twenty daphnids (4 replicates of 5 animals) were exposed to a Water Accommodated Fraction (WAF) of the test item at a nominal loading rate of 1.25, 2.5, 6.25, 12.5, 25, 50 and 100 mg/L for 48 hours at a temperature of 21 to 22 °C under static test conditions. The number of immobilised daphnia were recorded after 24 and 48 hours.

Total Organic Carbon (TOC) analysis of the test preparations at 0 hours showed measured concentrations ranging from less than the limit of quantification (determined to be 1.0 mg C/L) to 5.6 mg C/L. There was no significant difference in the measured concentrations of carbon at 48 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 Daphnia magna to the test item gave an EL50 (48h) value of 19 mg/L loading rate WAF. The No Observed Effect Loading Rate (NOELR) was 6.25 mg/L loading rate WAF and the Lowest Observed Effect Loading Rate (LOELR) was reported as 12.5 mg/L loading rate WAF.

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 medium was prepared as a Water Accommodated Fraction (WAF). Following a preliminary range-finding test, Pseudokirchneriella subcapitata was exposed to Water Accommodated Fractions (WAFs) of the test item over a range of nominal loading rates of 0.625, 1.25, 2.5, 5.0 and 10 mg/L (three replicate flasks per concentration) 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 5.0 and 10 mg/L loading rate WAF test preparations performed at 0 and 72 hours showed measured concentrations to range from 1.59 to 3.29 mg C/L. The control, 0.625, 1.25 and 2.5 mg/L loading rate WAF test preparations showed measured concentrations of less than the limit of quantification (LOQ) determined to be 1.0 mg C/L. 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.

Based on growth rate, exposure of Pseudokirchneriella subcapitata to the test item gave an EL50 (72h) value of 1.8 mg/L loading rate WAF, the No Observed Effect Loading Rate (NOELR) was reported as 0.625 mg/L and the Lowest Observed Effect Loading Rate (LOELR) was determined to be 1.25 mg/L. Based on yield, exposure of Pseudokirchneriella subcapitata to the test item gave an EL50 (72h) value of 1.2 mg/L loading rate WAF, the No Observed Effect Loading Rate (NOELR) was reported as0.625 mg/L and the Lowest Observed Effect Loading Rate (LOELR) was determined to be 1.25 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)".

 

Following a preliminary range-finding test, activated sewage sludge was exposed to an aqueous dispersion of the test item at concentrations of 320, 560 and 1000 mg/L (5 replicates) for a period of 3 hours at a measured temperature of 21 °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 8.6 mg/L, 95 % confidence limits 6.8 to 11 mg/L.