2H-Azepin-2-one, hexahydro-, polymer with 1,6-diisocyanatohexane

Endpoint summary

Additional information

Some of the studies were conducted with a 72% solution of the test substance. This does not affect the validity of the studies as the solvent increases the solubility of the test substance and thus represents worst case conditions.

A study was performed to assess the acute toxicity of a 72 % solution of 2H-Azepin-2-one, hexahydro-, polymer with 1,6-diisocyanatohexane in 2-methoxy-1-methylethylacetate to Danio rerio under static conditions. The study was conducted in accordance with EEC Method 1, Part C 'Acute toxicity for Fish' which is in most parts equivalent to the OECD Guideline 203 (1992). A group of seven fish was exposed to a limit test concentration of nominally 100 mg test item /L. Auxiliaries used to prepare the test media were an ultra turrax, a magnetic stirrer and folded filters. Observations were made on the number of dead fish and the incidence of sub-lethal effects after 2, 24, 48, 72 and 96 hours of exposure. At a limit test concentration of 100 mg/L one out of seven fish died. As none of the remaining 6 fish showed any symptoms of toxicity it can be concluded that the LC 50 is > 100 mg test item/L (72 mg 2H-Azepin-2-one, hexahydro-, polymer with 1,6-diisocyanatohexane/L) and no re-testing was performed. All results are expressed in terms of nominal concentrations. The determination of the DOC gave results corresponding to the (nominal) 28 mg 2-methoxy-1-methylethylacetate/L while insoluble oligomer was removed before test start.

The acute toxicity of the test substance to Daphnia magna was studied under static conditions according to OECD TGD 202 and EU method C2. Daphnids were exposed to the test substance at a saturated stock solution for 48 h. No effects were observed up to the limit of water solubility (0.33 mg/L) and thus the EC50 was determined to be >0.33 mg/L. This indicates that the test substance does not pose a significant hazard to aquatic invertebrates.

A study was performed to assess adverse effects of a 72 % solution of 2H-Azepin-2-one, hexahydro-, polymer with 1,6-diisocyanatohexane in 2-methoxy-1-methylethylacetate on the growth and the growth rate of freshwater algal species Desmodesmus subspicatus over several generations.

The study was conducted in accordance with EEC Methods Part C, and OECD Guideline No. 201.

Exponentially growing algal cells were exposed for a period of 72 hours to a limit test concentration of nominally 100 mg test item/L in water. Auxiliaries used to prepare the test media were an ultra turrax, a magnetic stirrer and aseptic filters.

The cell densities were measured at 24 hour intervals. Inhibition of the algal population was measured as reduction in growth (index b) and growth rate (index r), relative to control cultures grown under identical conditions. No toxic effects against algae at a limit test concentration of 100 mg test item/L, corresponding to 72 mg 2H-Azepin-2-one, hexahydro-, polymer with 1,6-diisocyanatohexane/L, were observed. All results are expressed in terms of nominal concentrations. The determination of the DOC indicated that the water soluble solvent was found in the test solution while the insoluble 2H-Azepin-2-one, hexahydro-, polymer with 1,6-diisocyanatohexane was removed before test start.

A study was performed to assess the toxicity of a 72 % solution of 2H-Azepin-2-one, hexahydro-, polymer with 1,6-diisocyanatohexane in 2-methoxy-1-methylethylacetate to bacteria. The study was conducted in accordance with the EEC Method, Part C.11 (1988) and OECD Guideline 209. The activated sludge was exposed to the test item at concentrations of 10, 100 and 1000 mg/L. The respiration rate of each mixture was determined after an aeration period of 3 hours. The test item showed 0.0 % respiration inhibition of activated sludge at a test item concentration of 1000 mg/L. The EC50 is higher than 1000 mg test item/L, corresponding to 720 mg 2H-Azepin-2-one, hexahydro-, polymer with 1,6-diisocyanatohexane/L. The effect value related to nominal concentration, since no analytical monitoring was performed