Reaction Products of Diphosphorus Pentaoxide with Alcohols, C14-18 even, salted with Amines, C12-14, Tert-alkyl

Endpoint summary

Additional information

Daphnia magna

 

A study was performed to assess the acute toxicity of the test item to Daphnia magna. The method 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 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 preliminary range-finding tests, twenty daphnids (4 replicates of 5 animals) were exposed to a Water Accommodated Fractions (WAFs) of the test item over a range of nominal loading rates (0.10, 0.32, 1.0, 3.2, 10, 32 and 100 mg/L) for 48 hours at a temperature of approximately 21°C under static test conditions. The number of immobilised Daphnia and any adverse reactions to exposure were recorded after 24 and 48 hours.

 

Analysis of the 0.32, 1.0, 3.2, 10 and 100 mg/L loading rates at 0 and 48 hours showed that measured concentrations of between 0.39 and 12 mg/L were obtained. 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 (48 h) value of 8.3 mg/L loading rate WAF (confidence limits 2.8-33 mg/L loading rate WAF). The No Observed Effect Loading Rate (NOEL) was determined to be 1.0 mg/L and the Lowest Observed Effect Loading Rate (LOEL) was reported as 3.2 mg/L.

Algae

 

A 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).

Following preliminary range-finding tests, Pseudokirchneriella subcapitata was exposed to Water Accommodated Fractions (WAFs) of the test item over a range of nominal loading rates of 0.10, 0.32, 1.0, 3.2 and 10 mg/L (three replicate flasks per concentration) for 72 hours, under constant illumination and shaking at a temperature of 24 ± 1 °C. Due to the need to test at relatively low test concentrations, the 0.10 and 0.32 mg/L loading rate WAFs were prepared as serial dilution from the 1.0 mg/L loading rate WAF.

 

Samples of the algal populations were removed daily and cell concentrations determined for each control and treatment group, using a Coulter Multisizer Particle Counter.

 

Analysis of the test preparations at 0 and 72 hours showed measured test concentrations to range from 0.031 to 2.1 mg/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.

 

Exposure of Pseudokirchneriella subcapitatata the test item gave EL50 based on growth rate of 0.75 mg/L loading rate WAF. The No Observed Effect Loading rate based on growth rate was 0.32 mg/L loading rate WAF. The Lowest Observed Effect Loading rate was 1.0 mg/L loading rate WAF.

Fish

A key study was performed to assess the acute toxicity of the test item to rainbow trout (Oncorhynchus mykiss). The method was designed to be compatible with the OECD Guidelines for Testing of Chemicals (1992) No 203 "Fish, Acute Toxicity Tes" 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, the test medium was prepared as a Water Accommodated Fraction (WAF) and, 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. The EL 50 value obtained from the algal growth inhibition study was the lowest of the two EL50 values and hence the test was conducted at a single loading rate of 0.75 mg/L.

Seven fish were exposed to a Water Accommodated Fraction (WAF) of the test item, at a single nominal loading rate of 0.75 mg/L for a period of 96 hours at a temperature of 14°C to 15°C under semi-static test conditions. The number of mortalities and any sublethal 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.

Analysis of the freshly prepared test media at zero and 72 hours showed that measured concentrations of 0.0682 and 0.138 mg/L were obtained respectively. Analysis of old test media at 24 and 96 hours gave measured concentrations of 0.0616 and 0.120 mg/L 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.

The acute toxicty of the test item to the freshwater fish rainbow trout (Oncorhynchus mykiss) was investigated using the threshold approach and gave a 96 hour LL50 value of greater than 0.75 mg/L loading rate WAF. The No Observed Effect Loading rate was 0.75 mg/L loading rate WAF.

Inhibition of sewage sludge micro-organisms

 

A study was performed to assess the effect of the test item on the respiration of activated sewage sludge. The method was designed to be compatible with 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 100, 180, 320 and 500 mg/L (5 replicates) for a period of 3 hours at temperatures of between 20 and 22 °C with the addition of a synthetic sewage as a respiratory substrate.

At the request off the Sponsor, an additional concentration was employed in order to determine the No Observed Effect Concentration (NOEC).

 

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 340 mg/L and a 3 -hour EC10 value of 74 mg/L. The No Observed Effect Concentration (NOEC) after 3 hours exposure was less than 100 mg/L. A NOEC was not achieved during the definitive test. The reference item gave a 3 -hour EC50 value of 6.8 mg/L (95 % confidence limits 5.3 to 8.8 mg/L).