Oxacycloheptadec-10-en-2-one

Endpoint summary

Description of key information

Short term toxicity to fish

In accordance with column 2 of Annex VIII of the REACH regulation, testing for this end point is considered scientifically unjustified since there are mitigating factors indicating that aquatic toxicity is unlikely to occur as the substance is highly insoluble in water. 

 

Short term toxicity to aquatic invertebrates

An acute immobilisation test was conducted for 48 hrs for assessing the effect of test chemical on Daphnia magna (Experimental study report, 2017). The test was performed in accordance to OECD guideline No. 202 “Daphnia sp., Acute Immobilization Test”. Own breeding stock at University of Chemistry and Technology, Prague of Daphnia magna was used as a test organism for the study. The stock solution 10.0 g/l was prepared by dissolving colourless liquid in acetone. Test solutions of required concentrations were prepared by mixing the stock solution of the test sample in reconstituted water.Nominal test chemical conc. used for the study were 0, 0, 0.6, 1.0, 1.7, 2.9, 4.9 and 8.3 mg/L, respectively. Study was performed using total 5 organisms per vessel/replicates in a static fresh water system. Daphnids were exposed to test chemical in 50 ml glass vessel in a volume of 25 ml of liquid solution containing both the chemical and media. The beakers were placed in a room at a temperature of 20±1°C. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration EC50 was calculated using nonlinear regression by the software Prism 4.0. On the basis of the effect of test chemical on the mobility of the test organism Daphnia magna, the 48 hr EC50 value was determined to be 1.7 mg/l with a 95% confidence interval value ranging from 1.5 to 2.0 mg/l, respectively. Thus, based on the EC50 value, test chemical can considered as toxic to aquatic invertebrates. Since, the test chemical is readily biodegradable in water, chemical can be considered as non-toxic to aquatic invertebrate and thus can be considered to be not classified as per the CLP classification criteria.

 

Toxicity to aquatic algae and cyanobacteria

A freshwater algal growth inhibition test was conducted for 72 hrs for assessing the effect of test chemical on green algae Pseudokirchneriella subcapitata. The test was performed in accordance to OECD guideline No. 201 – Alga growth inhibition test under static condition. Initial cell density of the culture was kept at 5000 cells/ml. OECD medium composed of macronutrients, micronutrients, alkaline EDTA solution and iron solution was used as a growth medium. The test solution was prepared by dissolving 100 mg of test chemical in 10 mL of solvent ethanol giving a concentration of 10000 mg/L. 1 mL of this solution was then diluted to 100 mL with OECD medium to get the final concentration of 100 mg/L. This followed the amount of solvent to be used as given in the OECD guideline 201. To have a better growth and visibility of cells, the initial cell count of the culture was kept 5000 cells/mL. Potassium dichromate (K2Cr2O7) was used as a reference substance. Test organisms were in length of 8 – 14 μm and weight of 2 - 3 μm. The cultures of algae were obtained from Microbiotest, Belgium and it is maintained with utmost care in the ESSEM facility at Nagpur. The growth medium used for the culturing of test organism is OECD Medium; which was prepared in ultra-pure, autoclaved water prior to any use. The temperatures were maintained at 21 to 24°C, controlled at ± 2°C. The Light intensity provided to the culture, it is measured each time and should be 4440  - 8880  LUX at the surface and a continuous light phase is maintained for the test duration. Pre-culture was set up two days prior to initiation of the test. It is grown under identical exposure conditions. A range finding study was conducted prior to main study with the test concentrations of 0.1, 1, 10, and 100 mg/L of test item along with control and solvent control groups containing OECD medium and test system. The percent inhibition of 11.111, 20.261, 72.549, and 92.81 % were observed at 72 h in the test concentrations of 0.1, 1, 10, and 100 mg/L respectively. Based on the result of range finding test, confirmatory test had was performed. Five test concentrations (number of replicates 03) were selected, which were arranged in geometric series with the factor of 1.7. Test chemical concentrations used for the study were 0 (control) and 8 mg/L, 13.6 mg/L, 23.12 mg/L, 39.304 mg/L and 66.817 mg/L. Test vessel were placed in orbital shaking incubator for 72 hrs at a temperature of 21 to 24 ± 2°C and with a continuous uniform illumination of 4440 - 8880 lux. The speed of the orbital shaking incubator was set at a 120 ±10 rpm throughout the study period. The cultures were counted and observed daily with the help of a microscope. All control, solvent control and  test vessel conc. were performed in three replicates. The pH value in control vessels was determined to be in range of  7.67 to 8.30, in solvent control it was 7.68 to 8.45. And in test concentrations vessels the pH was determined to be in range of  7.58 to 8.44. The 72 hr EC50 value of the reference substance (K2Cr2O7) was determined to be 2.8063 mg/l. Percent yield was found to be 18.75, 46.875, 64.063, 82.813, and 87.5 % for test concentration 8, 13.6, 23.12, 39.304, and 66.817 % respectively. The biomass of the control cultures have increased exponentially by a factor of 16 (specific growth rate of 0.92 day-1) within the 72 hr test periods. The coefficient of variation of average specific growth rates during the whole test period in replicate control cultures must not exceed 7% (i.e., reported to be 0.830%) and the mean coefficient of variation of specific growth rate was not exceeded 35% (i.e., reported to be 21.783 %), respectively thus fulfilling the validity criterion. As the concentration of the test chemical being tested has been satisfactorily maintained within ± 20 % of the nominal concentration throughout the test. Therefore, the analysis of the results was based on nominal concentration. Based on the growth inhibition of green alga Pseudokirchneriella subcapitata by the test chemical, the 72 hr median effect concentration (ErC50) value was determined to be > 16.6041 mg/l (nominal conc.) ) with 95% CI of 14.4327 to 18.8284 mg/L. Since, the test chemical is readily biodegradable in water, chemical can be considered as non-toxic to aquatic algae and thus can be considered to be "not classified' as per the CLP classification criteria. 

 

Toxicity to microorganisms

In accordance with column 2 of Annex VIII of the REACH regulation, testing for this end point does not need to be conducted since there are mitigating factors indicating that aquatic toxicity is unlikely to occur as the substance is highly insoluble in water. 

Additional information

Short term toxicity to fish

In accordance with column 2 of Annex VIII of the REACH regulation, testing for this end point is considered scientifically unjustified since there are mitigating factors indicating that aquatic toxicity is unlikely to occur as the substance is highly insoluble in water. 

 

Short term toxicity to aquatic invertebrates

Experimental study of the test chemical was reviewed for the short term toxicity to aquatic invertebrates end point which is summarized as below:

 

In an experimental study from study report (2017),an acute immobilisation test was conducted for 48 hrs for assessing the effect of test chemical on Daphnia magna. The test was performed in accordance to OECD guideline No. 202 “Daphnia sp., Acute Immobilization Test”. Own breeding stock at University of Chemistry and Technology, Prague of Daphnia magna was used as a test organism for the study. The stock solution 10.0 g/l was prepared by dissolving colourless liquid in acetone. Test solutions of required concentrations were prepared by mixing the stock solution of the test sample in reconstituted water.Nominal test chemical conc. used for the study were 0, 0, 0.6, 1.0, 1.7, 2.9, 4.9 and 8.3 mg/L, respectively. Study was performed using total 5 organisms per vessel/replicates in a static fresh water system. Daphnids were exposed to test chemical in 50 ml glass vessel in a volume of 25 ml of liquid solution containing both the chemical and media. The beakers were placed in a room at a temperature of 20±1°C. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration EC50 was calculated using nonlinear regression by the software Prism 4.0. On the basis of the effect of test chemical on the mobility of the test organism Daphnia magna, the 48 hr EC50 value was determined to be 1.7 mg/l with a 95% confidence interval value ranging from 1.5 to 2.0 mg/l, respectively. Thus, based on the EC50 value, test chemical can considered as toxic to aquatic invertebrates. Since, the test chemical is readily biodegradable in water, chemical can be considered as non-toxic to aquatic invertebrate and thus can be considered to be not classified as per the CLP classification criteria.

 

Short term toxicity to aquatic invertebrates endpoint can also be considered for waiver as per in accordance with column 2 of Annex VII of the REACH regulation, testing for this end point is considered scientifically unjustified since there are mitigating factors indicating that aquatic toxicity is unlikely to occur as the substance is highly insoluble in water.

 

Toxicity to aquatic algae and cyanobacteria

Experimental study of the test chemical was reviewed for the toxicity to aquatic algae and cyanobacteria end point which is summarized as below:

A freshwater algal growth inhibition test was conducted for 72 hrs for assessing the effect of test chemical on green algae Pseudokirchneriella subcapitata. The test was performed in accordance to OECD guideline No. 201 – Alga growth inhibition test under static condition. Initial cell density of the culture was kept at 5000 cells/ml. OECD medium composed of macronutrients, micronutrients, alkaline EDTA solution and iron solution was used as a growth medium. The test solution was prepared by dissolving 100 mg of test chemical in 10 mL of solvent ethanol giving a concentration of 10000 mg/L. 1 mL of this solution was then diluted to 100 mL with OECD medium to get the final concentration of 100 mg/L. This followed the amount of solvent to be used as given in the OECD guideline 201. To have a better growth and visibility of cells, the initial cell count of the culture was kept 5000 cells/mL. Potassium dichromate (K2Cr2O7) was used as a reference substance. Test organisms were in length of 8 – 14 μm and weight of 2 - 3 μm. The cultures of algae were obtained from Microbiotest, Belgium and it is maintained with utmost care in the ESSEM facility at Nagpur. The growth medium used for the culturing of test organism is OECD Medium; which was prepared in ultra-pure, autoclaved water prior to any use. The temperatures were maintained at 21 to 24°C, controlled at ± 2°C. The Light intensity provided to the culture, it is measured each time and should be 4440  - 8880  LUX at the surface and a continuous light phase is maintained for the test duration. Pre-culture was set up two days prior to initiation of the test. It is grown under identical exposure conditions. A range finding study was conducted prior to main study with the test concentrations of 0.1, 1, 10, and 100 mg/L of test item along with control and solvent control groups containing OECD medium and test system. The percent inhibition of 11.111, 20.261, 72.549, and 92.81 % were observed at 72 h in the test concentrations of 0.1, 1, 10, and 100 mg/L respectively. Based on the result of range finding test, confirmatory test had was performed. Five test concentrations (number of replicates 03) were selected, which were arranged in geometric series with the factor of 1.7. Test chemical concentrations used for the study were 0 (control) and 8 mg/L, 13.6 mg/L, 23.12 mg/L, 39.304 mg/L and 66.817 mg/L. Test vessel were placed in orbital shaking incubator for 72 hrs at a temperature of 21 to 24 ± 2°C and with a continuous uniform illumination of 4440 - 8880 lux. The speed of the orbital shaking incubator was set at a 120 ±10 rpm throughout the study period. The cultures were counted and observed daily with the help of a microscope. All control, solvent control and  test vessel conc. were performed in three replicates. The pH value in control vessels was determined to be in range of  7.67 to 8.30, in solvent control it was 7.68 to 8.45. And in test concentrations vessels the pH was determined to be in range of  7.58 to 8.44. The 72 hr EC50 value of the reference substance (K2Cr2O7) was determined to be 2.8063 mg/l. Percent yield was found to be 18.75, 46.875, 64.063, 82.813, and 87.5 % for test concentration 8, 13.6, 23.12, 39.304, and 66.817 % respectively. The biomass of the control cultures have increased exponentially by a factor of 16 (specific growth rate of 0.92 day-1) within the 72 hr test periods. The coefficient of variation of average specific growth rates during the whole test period in replicate control cultures must not exceed 7% (i.e., reported to be 0.830%) and the mean coefficient of variation of specific growth rate was not exceeded 35% (i.e., reported to be 21.783 %), respectively thus fulfilling the validity criterion. As the concentration of the test chemical being tested has been satisfactorily maintained within ± 20 % of the nominal concentration throughout the test. Therefore, the analysis of the results was based on nominal concentration. Based on the growth inhibition of green alga Pseudokirchneriella subcapitata by the test chemical, the 72 hr median effect concentration (ErC50) value was determined to be > 16.6041 mg/l (nominal conc.) ) with 95% CI of 14.4327 to 18.8284 mg/L. Since, the test chemical is readily biodegradable in water, chemical can be considered as non-toxic to aquatic algae and thus can be considered to be "not classified' as per the CLP classification criteria. 

Toxicity to aquatic algae and cyanobacteria endpoint can also be considered for waiver as per in accordance with column 2 of Annex VII of the REACH regulation, testing for this end point is considered scientifically unjustified since there are mitigating factors indicating that aquatic toxicity is unlikely to occur as the substance is highly insoluble in water.

 

 

 

Toxicity to microorganisms

In accordance with column 2 of Annex VIII of the REACH regulation, testing for this end point does not need to be conducted since there are mitigating factors indicating that aquatic toxicity is unlikely to occur as the substance is highly insoluble in water. 

 

On the basis of the available information of aquatic toxicity studies, it can be concluded that the test chemical can be considered as non-toxic to aquatic organisms at environmental relevant concentrations and thus can be considered to be ‘Not classified’ as per CLP classification criteria.