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Ecotoxicological information

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Additional information

Experimental data for 1,2,3-Propanetriol, homopolymer, diisooctadecanoate (CAS 63705-03-3) are available investigating the short-term toxicity to fish, aquatic invertebrates and algae. No effects on either fish or algae were observed up to the limit of water solubility (< 0.15 mg/L). Available data investigating the short-term toxicity of the substance to aquatic invertebrates resulted in a 48h-EC50 value > 1 and < 10 mg/L (EL50 = 5.05 mg/L based on a statistical analysis performed by qualified scientists of the owner company). The observed EC50 value is much higher than the solubility of the UVCB substance in water (< 0.15 mg/L). Therefore, in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5 read across to the structurally similar analogue substances isooctadecanoic acid, mono- and diester with glycerol (CAS No. 97358-80-0) and Glycerides, C16-18 and C18-unsatd. (CAS 67701-30-8) was conducted in order to verify if metabolites of the ester components may have been caused the toxicity. Based on the results from the structurally related read-across substances (in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5), it can be concluded that the ester components most probably did not cause the toxicity observed in the acute toxicity test with the target substance. It is assumed that metabolites of the isooctadecanoic acid component may have been caused the toxicity.

1,2,3-Propanetriol, homopolymer, diisooctadecanoate did not cause inhibition of respiration in a study according to OECD 209 with activated sludge microorganisms (EC10 (3 h) > 1000 mg/L). Thus, the overall potential to cause inhibition of activated sludge microorganisms is low and significant inhibition of the subsequent degradation process in sewage treatment plants is not expected.

Experimental data for 1,2,3-Propanetriol, homopolymer, diisooctadecanoate (CAS 63705-03-3) are available investigating the long-term toxicity to daphnia and algae. No effects up to the solubility of the substance in water were observed for algae. The lowest NOELR value determined for Daphnia magna is 4 mg/L based on loading rate WAFs. The following endpoints were recorded: (1) Mean cumulative number of offspring per survivor, (2) the total number of living offspring produced at the end of the test per parent daphnid at the start of the test (excluding parental accidental and/or inadvertent immobilization from the analysis), (3) immobilization of the parent daphnids, (4) rate of population growth, (5) age of first reproduction and (6) growth of parent animals. The 21-d NOELR value for the cumulative number of offspring per survivor (= reproduction) is determined to be above the highest test concentration of 8 mg/L. However, the 21-d NOELR value for parental mortality and total number of living offspring produced at the end of the test per parent daphnid at the start of the test (= mortality influenced reproduction) is determined to be 4 mg/L based on the water accommodated fraction of nominal concentrations. It can be concluded that effects on reproduction within the solubility of the target substance in water is not to be expected, but immobilisation may occur at concentrations above 4 mg/L loading rate. Since a dose-response pattern for immobilization is observed and the toxicity is in the same range as in the short-term toxicity test it is assumed that the same toxic metabolite is responsible for the toxicity in both tests. Thus, in order to protect the environment for any adverse effect caused by the UVCB substance the 21-d NOELR is determined to be 4 mg/L based on the mortality of parental daphnids.

No long-term toxicity test with fish is available. In Annex IX, column II (9.1) of Regulation (EC) No 1907/2006, it is laid down that a long-term toxicity test shall be proposed by the registrant if the chemical safety assessment indicates the need to investigate further the effects on freshwater fish. The hazard assessment of 1,2,3-Propanetriol, homopolymer, diisooctadecanoate however do not indicate that fish is more sensitive than aquatic invertebrates for which a long-term toxicity test is available. Therefore, no further test with fish is considered to be necessary.