Isononyl acetate

Endpoint summary

Description of key information

Short term toxicity to aquatic invertebrates

Using the OECD QSAR toolbox version 3.4 (2017) with log kow as the primary descriptor and considering the five closest read across substances, the short term toxicity on aquatic invertebrates was predicted for target substance 3,5,5-trimethylhexyl acetate (CAS no. 40379 -24 -6). EC50 value was estimated to be 116 mg/l for Daphnia magna for 48 h duration. Based on this value it can be concluded that the substance 3,5,5-trimethylhexyl acetate is considered to be non-toxic to aquatic environment and can be considered to be not classified as per the CLP classification criteria.

Toxicity to aquatic algae and cyanobacteria

Using the OECD QSAR toolbox version 3.4 (2017) with log kow as the primary descriptor and considering the five closest read across substances, the short term toxicity on aquatic algae and cyanobacteria was predicted for target substance 3,5,5-trimethylhexyl acetate (CAS no. 40379 -24 -6). EC50 value was estimated to be 120 mg/l for Desmodesmus subspicatus for 72 h duration. Based on this value it can be concluded that the substance 3,5,5-trimethylhexyl acetate is considered to be non-toxic to aquatic environment and can be considered to be not classified as per the CLP classification criteria.

Additional information

Short term toxicity to aquatic invertebrates

Predicted data for the target chemical 3,5,5-trimethylhexyl acetate (CAS No. 40379-24-6) and various supporting weight of evidence studies for its read across substanceswere reviewed to summarize the following information:

 

Short term toxicity on aquatic invertebrate of target chemical3,5,5-trimethylhexyl acetate (CAS No. 40379-24-6) is predicted using the OECD QSAR toolbox version 3.4 with log kow as the primary descriptor and considering the five closest read across substances (2017). On the basis of effects observed in a static freshwater system, the effect concentration EC50 value for the substance is estimated to be 116 mg/l for Daphnia magna for 48 hr duration.Based on this value it can be concluded that the substance3,5,5-trimethylhexyl acetateis considered to be non-toxic to aquatic environment and can be considered to be not classified as per the CLP classification criteria.

 

In an another prediction done using the three different models i.e, Battery, Leadscope and SciQSAR present within Danish QSAR database, the short term toxicity on aquatic invertebrates was predicted for 3,5,5-trimethylhexyl acetate (CAS no. 40379 -24 -6). The average EC50 value was given by the third model i.e, Battery model. On the basis of effects observed in a static freshwater system, the effect concentration EC50 value for the 3,5,5-trimethylhexyl acetate is estimated to be 594 mg/l for Daphnia magna during 48 hr exposure duration. Thus, on the basis of EC50 value, it can be concluded that the 3,5,5-trimethylhexyl acetate was likely to be non-toxic to aquatic invertebrates at environmentally relevant concentrations and can be considered not-classified as per the CLP classification criteria.

 

In a weight of evidencestudy from experimental study report (ABITEC, s.r.o., Sustainability Support Services (Europe) AB, Study no. 112-14-2/SSS/2018, 2017) of the read across chemical Octyl Acetate (CAS no. 112-14-1), determination of the inhibition of the mobility of daphnids was carried out with the read across substance Octyl Acetate according to OECD Guideline 202. The test substance was tested at the limit concentration of 100 mg/l. Effects on immobilisation and growth inhibition were observed for 48 hours. The effective concentration (EC8) for the test substance, Octyl Acetate in Daphnia magna was determined to be 100 mg/L for immobilisation and inhibition effects where 8% daphnia inhibited. As the EC8 was at 100 mg/l, thus EC50 was greater than 100 mg/l. So on that basis chemical Octyl Acetate was consider to be not toxic. This value indicates that the substance Octyl Acetate is likely to be non-hazardous to aquatic invertebrates and cannot be classified as toxic as per the CLP criteria.

 

For the read across chemical 3-methylbutyl 2-hydroxybenzoate (CAS no. 87-20-7) from peer reviewed journal (A.M. Api et. al; 2015), short term toxicity test to Daphnia magna was conducted to evaluate the effect of read across chemical 3-methylbutyl 2-hydroxybenzoate. 48 hrs short term toxicity test was conducted on Daphnia magna under static conditions. The 48 hr EC0 and EC100 value was determined to be 2 and 4 mg/l. The geometric mean was determined to be 2.8 mg/L. Thus, EC50 can be considered to be 2.8 mg/L. Based on the result the 3-methylbutyl 2-hydroxybenzoate can be considered as toxic to aquatic organisms. Since the chemical is readily biodegradable in nature, chemical 3-methylbutyl 2-hydroxybenzoate can be considered as non-toxic to aquatic organisms and thus can be considered to be not classified as per the CLP classification criteria.

 

Another short term toxicity test was conducted on Daphnia magna for 24 hrs for the read across chemical 3-methylbutyl 2-hydroxybenzoate (CAS no. 87-20-7) (A.M. Api et. al; 2015). The study was based on the effect of the read across chemical 3-methylbutyl 2-hydroxybenzoate Daphnia magna on under static conditions. The 24 hrs EC50 value was determined to be 4.5 mg/L. Based on the EC50 value, the chemical 3-methylbutyl 2-hydroxybenzoate can be considered as toxic to aquatic organisms. Since the chemical is readily biodegradable in nature, chemical 3-methylbutyl 2-hydroxybenzoate can be considered as non-toxic to aquatic organisms and thus can be considered to be not classified as per the CLP classification criteria.

 

Thus, based on the overall reported results for target chemical3,5,5-trimethylhexyl acetate(OECD QSAR toolbox version 3.3 and Danish QSAR database, 2017) and for its read across substance (fromstudy report and peer reviewed journal),it can be concluded that the test substance3,5,5-trimethylhexyl acetatecan be considered as non-toxic to aquatic environment and can be considered to be notclassified as per the CLP classification criteria.

Toxicity to aquatic algae and cyanobacteria

Predicted data for the target chemical 3,5,5-trimethylhexyl acetate (CAS No. 40379-24-6) and various supporting weight of evidence studies for its read across substanceswere reviewed for toxicity to aquatic algae and cyanobacteria endpoint to summarize the following information:

 

Short term toxicity on aquatic algae and cyanobacteria of target chemical3,5,5-trimethylhexyl acetate (CAS No. 40379-24-6) is predicted using the OECD QSAR toolbox version 3.4 with log kow as the primary descriptor and considering the five closest read across substances (2017).On the basis of effects observed in a static freshwater system, the effect concentration EC50 value for the substance is estimated to be 120 mg/l for Desmodesmus subspicatus for 72 duration. Based on this value it can be concluded that the substance3,5,5-trimethylhexyl acetateis considered to be non-toxic to aquatic environment and can be considered to be not classified as per the CLP classification criteria.

 

In a weight of evidencestudy from experimental study report (ABITEC, s.r.o., Sustainability Support Services (Europe) AB, Study no. 112-14-2/SSS/2018, 2017) of the read across chemical Octyl Acetate (CAS no. 112-14-1), Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance read across Octyl Acetate according to OECD Guideline 201. The test substance was dissolved in OECD growth medium and tested at the limit concentration of 100 mg/l. Effects on the growth rate of the organism were studied. The effective concentration (EC2.1) for the test substance, Octyl Acetate, in Desmodesmus subspicatus was determined to be 100 mg/L. As the limit test was performed at 100 mg/l where only 2.1% inhibition of algal cells was occurred. Thus it was estimated that the EC50 concentration was greater than 100 mg/l. Based on this EC2.1 % inhibition value and after comparing with CLP criteria for aquatic classification of the substance it is concluded that the substance Octyl Acetate does not exhibit toxicity to aquatic algae (Desmodesmus subspicatus) and cannot be classified as toxic as per the CLP classification criteria.

 

For the read across chemical 2-methyl propyl acetate (CAS no. 110-19-0) from peer reviewed journal (G. BRINGMANN and R. KUHN; 1980), short term toxicity to Entosiphon Sulcatum study was carried out for 72 hrs.The study was based on the effects of the read across compound 2-methyl propyl acetate on Entosiphon Sulcatum in a static fresh water system. Test chemical of known concentration was prepared in sterile double distilled water.For maintenance of the test strain of Entosiphon sulcatum, continuously inoculate the expected requirednumber of stock cultures at 72 h or 96 h intervals. Forthis, mix 8 ml of stock solution I and 8 ml of steriledouble-distilled water in 300-ml Erlenmeyer flasksstoppered with metal caps and add 2 ml of a stock culture and 2 ml of the adjusted bacterial suspensionfor Entosiphon stock cultures. Store stock cultures at25°C. Before inoculation control the flasks containingthe stock cultures by means of an inverse microscope.Escherichia coliwas used as a feeding material of the test organism Entosiphon sulcatum. Prepare two parallel dilution series in 300-ml Erlenmeyer flasks stoppered with metal caps. The dilutions will contain 1 part v/v each of pollutant solution in 20to 214partsv/vof mixture. Test vessel contain the known conc. of chemical and test organism. Leave the test culture at 25ᵒC for 72 hrs. Before measurement, control each flask by means of an inverse microscope. Add 10% of a 1.1% NaNO3 solution in double-distilled water filtered through a membrane filter (pore size 0.2/µm), and determine the number of protozoaby means of a cell counter.Pollutant concentrations at which the onset of inhibitory action was observed have been obtained by mathematical evaluation of counts. The term counts corresponds to impulses indicated by the coulter counter.Based on the onset of the inhibitory effect on population of the test organismEntosiphon Sulcatum, the 72 hr LOEC value was determined to be 411 mg/l, respectively and therefore, the 72 hr EC50 value was expected to be > 411 mg/l. Thus, based on the EC50 value (> 411 mg/l), it can be concluded that the substance 2-methyl propyl acetate can be considered as non-toxic to aquatic organisms and thus can be considered to be not classified as per the CLP classification criteria.

 

Another short term toxicity to green algae study was carried out for 72 hrs for the read across compound 2-methyl propyl acetate (CAS no. 110-19-0) (J-CHECK, 2017). The study was based on the effects of the read across compound 2-methyl propyl acetate on green algae in a static fresh water system. Based on effect on growth rate of the test organism green algae, the 72 hr EC50 and NOEC value was determined to be 370 and 95 mg/l, respectively and on the basis of AUG, the 72 hr EC50 and NOEC value was determined to be 250 and 110 mg/l, respectively. Thus, based on the EC50 value, it can be concluded that the substance 2-methyl propyl acetate can be considered as non-toxic to aquatic organisms and thus can be considered to be not classified as per the CLP classification criteria.

 

For the same read across chemical 2-methyl propyl acetate (CAS no. 110-19-0) from authoritative database (HSDB and Ecotox, 2017), short term toxicity to Chlorococcales (green algae) study was carried out for 24 hrs. The study was based on the effects of the test compound 2-methyl propyl acetate(CAS no. 110-19-0) on Chlorococcales in a static fresh water system. Chlorococcales (green algae) was used as a test organism. Based on effect on physiology of the test organism Chlorococcales, the 24 hr EC50 value was determined to be 600 mg/l, respectively. Thus, based on the EC50 value, it can be concluded that the substance 2-methyl propyl acetate can be considered as non-toxic to aquatic organisms and thus can be considered to be not classified as per the CLP classification criteria.

 

In a weight of evidence study from peer reviewed journal (Monika Nendzal and Andrea Wenzel, 2006) of the read across chemical 2-methylpropyl 2-methylprop-2-enoate (CAS no. 97-86-9), short term toxicity to Scenedesmus subspicatus (green algae) study was carried out for 30 or 60 mins. The study was based on the effects of the read across compound 2-methylpropyl 2-methylprop-2-enoate(CAS no. 97-86-9) on Scenedesmus subspicatus in a static fresh water system. Inhibition of photosynthesis (EC50) was determined from effects on O2-production in unicellular green algae Scenedesmussubspicatus, cultured according to OECD-Guideline No. 201. 5 ml of algae suspension (2 million cells/ml) were collected on a filter paper disk (diameter 13 mm). After incubation in test solution for 30 or 60 min, the disk was placed on top of the electrode of the measuring chamber (PHOSY-Mess 2000, Specht, Germany). The Clark-electrode was placed in the measuring chamber (25°C, 100% exposure (ca. 1.9 klux), measuring solution: 0.05 M KHCO3). After a dark phase of 5 min (O2 fell to nearly 0 mg/l), the O2-production [mg/l] was recorded for 14 min. On the basis of inhibition of photosynthesis of the test organism Scenedesmus subspicatus (green algae), the EC50 value was determined to be 442 mg/l, respectively. Thus, based on this value, it can be concluded that the substance 2-methylpropyl 2-methylprop-2-enoate can be considered as non-toxic to aquatic organisms and thus cannot be classified as hazardous as per the CLP criteria.

 

Thus, based on the overall reported results for target chemical3,5,5-trimethylhexyl acetate(OECD QSAR toolbox version 3.4, 2017) and for its read across substance (from study report,authoritative database J-CHECK, HSDB, ECOTOX and peer reviewed journals),it can be concluded that the test substance3,5,5-trimethylhexyl acetatecan be considered as non-toxic to aquatic environment and can be considered to be notclassified as per the CLP classification criteria.

On the basis of above mentioned available information for short term toxicity to aquatic invertebrates and toxicity to aquatic algae and cyanobacteria,test substance 3,5,5-trimethylhexyl acetate can be considered as non-toxic to aquatic environment and can be considered to be notclassified as per the CLP classification criteria.