Phenethyl butyrate

Endpoint summary

Description of key information

Short term toxicity to fish:

Short term effect of test chemical were determine and estimated on the mortality of fish using (EPI suite, ECOSAR version 1.1, 2016) were conducted to assess toxic effects of test chemical and the results were predicted. The data was based on the effects of the test compound on fish in a static fresh water system. The lethal concentration (LC50) for test chemical was predicted to be 6.348 mg/l on the basis of mortality effects. Based on lethal concentration, it can be concluded that test chemical considered as toxic to fish and thus can be classified as aquatic chronic category 2. Since the chemical is readily biodegradable in nature thus it is considered as non-toxic to fish and thus cannot be classified as hazardous as per the CLP criteria.

Short term toxicity to aquatic invertebrates:

Determination of the inhibition of the mobility of daphnids was carried out with the test substance. Study was conducted according to OECD Guideline 202. The stock solution 100 g/l was prepared by dissolving colourless liquid in acetone. Test solutions of required concentrationas were prepared by mixing the stock solution of the test sample with reconstituted test water. The test substance tested at the 0, 0, 12, 25, 50, 100 mg/l nominal concentrations. Effects on immobilisation were observed for 48 hours. 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 non linear regression by the software Prism 4.0. The median effective concentration (EC50) for the test substance on daphnia magna was determined to be 28 mg/L for immobilisation effects. This value indicates that the substance is likely to be hazardous to aquatic invertebrates and can be classified as aquatic chronic 3 as per the CLP criteria. But as the chemical was readily biodegradable in water thus chemical was consider as nontoxic and not classified as per the CLP classification criteria.

Toxicity to aquatic algae and cyanobacteria:

Objective of this study was to determine the short term toxicity or any effects of test chemical on aquatic algae Desmodesmus subspicatus and was performed according to the OECD Guideline 201 (Alga, Growth Inhibition Test) in a static system. The stock solution 100 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 with OECD growth medium and inoculum culture. Chemical tested at the 0, 0, 5, 10, 20, 40, 60, 80 mg/l nominal concentrations. Effects on the growth rate of the organism were studied. 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 non linear regression by the software Prism 4.0. The median effective concentration (ErC50) for the test substance on Desmodesmus subspicatus was determined to be 47.4 mg/L. This value indicates that the substance is likely to be hazardous to aquatic invertebrates and can be classified as aquatic chronic 3 as per the CLP criteria. But as the chemical was readily biodegradable in water thus chemical was consider as nontoxic and not classified as per the CLP classification criteria.

Toxicity to microorganisms:

WoE 2: The impairment growth concentration (IGC50) of test chemical in microorganism [Tetrahymena pyriformis] in a 48 hr study on the basis of growth inhibition effect using a short-term, static protocol was datarmine to be 377 mg/L.

WoE 3: The toxicity threshold (TT) of test material was determined to be 236 mg/l for Entosiphon sulcatum. Therefore LOEC was considered to be 236 mg/l for 72h in Entosiphon sulcatum.

Additional information

Short term toxicity to fish:

Various experimental and predicted studies available for the test chemical and structually and functionally similar read across chemical from peer reviewed journals were reviewed to determine the toxic nature of the test chemical on the mortality of fish. The studies are as mention below:

In the first data short term effect of test chemical were determine and estimated on the mortality of fish using (EPI suite, ECOSAR version 1.1, 2016) were conducted to assess toxic effects of test chemical and the results were predicted. The data was based on the effects of the test compound on fish in a static fresh water system. The lethal concentration (LC50) for test chemical was predicted to be 6.348 mg/l on the basis of mortality effects. Based on lethal concentration, it can be concluded that test chemical considered as toxic to fish and thus can be classified as aquatic chronic category 2. Since the chemical is readily biodegradable in nature thus it is considered as non-toxic to fish and thus cannot be classified as hazardous as per the CLP criteria.

Prediction done using average value of both models i.e Leadscope and SciMatics SciQSAR model and the result were predicted in Battery model. Based on the QSAR prediction done using the Danish (Q)SAR Database, the 96 hours LC50 was estimated to be 3.31 mg/l on Pimephales promelas for test substance with mortality effects. Thus based on this value it can be concluded that the substance can be classified as toxic as per the criteria of CLP regulation. But as the chemical readily biodegrade in water, thus on that basis, chemical consider to be nontoxic and not classified as per the CLP classification criteria.

Above predicted data was supported by the another data from experimental report. Study was conducted to assess the effect of test chemical on the mortality of fish Danio rerio. Test conducted according to OECD Guideline 203 (Fish, Acute Toxicity Test). Therefore the stock solution prepared as 2g /4 liter, with the concentration of 500 mg/L, and was kept for 4 hours stirring. After the completion of stirring, the sample was run through HPLC system for getting the actual water solubility of the test substance. The actual solubility obtained was 122.66 mg/L. From this stock solution further test concentrations were prepared for achieving test concentrations of 6.25mg/L, 12.5mg/L, 25mg/L, 50mg/L, 100mg/L, respectively. Potable water (passed through reverse osmosis system) was used and Zebra FishDanio reriowere exposed to these concentration for 96 hours. Bowl aquaria containing 2 liters of potable water (passed through reverse osmosis system) were loaded with 8 fishes. A static procedure was used for the study and it was conducted in compliance with the OECD guideline 203. After 96 hours of exposure to test item to various nominal test concentrations, LC50 was determine to be 12.5 mg/l . Based on the LC50, it can be consider that the chemical was toxic and can be consider to be classified aq aquatic chronic 3 as per the CLP classification criteria. But on the basis of readily biodegradability of test chemical, chemical consider to be nontoxic and not classified as per the CPL classification criteria.

In fourth experimental study from peer reviewed journal short term toxicity study to Cyprinus carpio was carried out for 44 hrs. Test was performed under flow through conditions. After exposure of test animal to different dose conc. i.e, at 68, 130 and 146 mg/l of test chemical. Glass-fronted, fiberglass tanks were used in the study, no effects were observed on the test animal. Thus, the NOEC value was consider to be 146 mg/l respectively.

This fifth study was designed to access the toxic effects of the test compound on the Zebra fish (Danio rerio). Bowl aquaria containing 4 liters of potable water (passed through reverse osmosis system) were loaded with 8 fishes each. A static procedure was used for the study and it was conducted in compliance with the OECD guideline 203.The nominal concentration selected for the experiment were and test fish were exposed to 6.25 mg/L, 12.5 mg/L, 25 mg/L, 50 mg/L & 100 mg/L concentrations for 96 hours. The test substance was moderately soluble in water. Initially, stock solution was prepared by dissolving 1ml of the test substance in 1 liter of potable water (passed through reverse osmosis system) with 24 hrs of continuous stirring. From this stock solution, further test concentration was prepared for achieving test concentrations of 6.25 mg/L, 12.5 mg/L, 25 mg/L, 50 mg/L & 100 mg/L, respectively.  The median lethal concentration (LC50) for test chemical on Danio rerio in a 96 hours study on the basis of mortality effect was determine to be >12.5 mg/L. Thus, on the basis of this LC50 value and according to CLP criteria for aquatic classification of the substance, it is concluded that the substance, is classified under aquatic chronic 3 category and exhibits short term toxicity to fish. But as the chemical was readily biodegradable in water, thus on that basis, chemical consider to be nontoxic and not classified as per the CLP classification criteria.

Thus based on the overall studies and results, chemical consider to be nontoxic and not classified as per the CLP classification criteria.

Short term toxicity to aquatic invertebrates:

Determination of the inhibition of the mobility of daphnids was carried out with the test substance. Study was conducted according to OECD Guideline 202. The stock solution 100 g/l was prepared by dissolving colourless liquid in acetone. Test solutions of required concentrationas were prepared by mixing the stock solution of the test sample with reconstituted test water. The test substance tested at the 0, 0, 12, 25, 50, 100 mg/l nominal concentrations. Effects on immobilisation were observed for 48 hours. 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 non linear regression by the software Prism 4.0. The median effective concentration (EC50) for the test substance on daphnia magna was determined to be 28 mg/L for immobilisation effects. This value indicates that the substance is likely to be hazardous to aquatic invertebrates and can be classified as aquatic chronic 3 as per the CLP criteria. But as the chemical was readily biodegradable in water thus chemical was consider as nontoxic and not classified as per the CLP classification criteria.

Toxicity to aquatic algae and cyanobacteria:

Objective of this study was to determine the short term toxicity or any effects of test chemical on aquatic algae Desmodesmus subspicatus and was performed according to the OECD Guideline 201 (Alga, Growth Inhibition Test) in a static system. The stock solution 100 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 with OECD growth medium and inoculum culture. Chemical tested at the 0, 0, 5, 10, 20, 40, 60, 80 mg/l nominal concentrations. Effects on the growth rate of the organism were studied. 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 non linear regression by the software Prism 4.0. The median effective concentration (ErC50) for the test substance on Desmodesmus subspicatus was determined to be 47.4 mg/L. This value indicates that the substance is likely to be hazardous to aquatic invertebrates and can be classified as aquatic chronic 3 as per the CLP criteria. But as the chemical was readily biodegradable in water thus chemical was consider as nontoxic and not classified as per the CLP classification criteria.

Toxicity to microorganism:

Various studies available for the test chemical and structually and functionally similar read across chemical from peer reviewed journals were reviewed to determine the toxic nature of the test chemical on the growth and other activity of of microorganism. The studies are as mention below:

In the first experimental study from peer reviewed journal a short-term, static protocol using the common freshwater ciliate Tetrahymena pyriformis (strain GL-C) was reported. The 50% impairment growth concentration (IGC 50) is the endpoint of choice. Cultures were reared in 50 mL of a semi defined medium in 250-mL Erlenmeyer flasks. Definitive test replicates consisted of a minimum of 5 different concentrations of each test material. Duplicate flasks were inoculated to an initial density of 2500 cells/ mL with log-growth phase ciliates. Following 40 h of incubation at 27 deg C, population density was measured spectrophotometrically and 50% effect levels were determined. The impairment growth concentration (IGC50) of test chemical in microorganism [Tetrahymena pyriformis] in a 48 hr study on the basis of growth inhibition effect using a short-term, static protocol was datarmine to be 377 mg/L.

First study was supported by the second study from peer reviewed journal. In toxicity to microorganism study for test material the biological effect was evaluated by using analogous methods of the cell multiplication inhibition test. For maintenance of the test strain of Entosiphon sulcatum continuously inoculate the expected required number of stock cultures at 72 h or 96 h intervals. For this, mix 8 ml of stock solution I and 8 ml of sterile double-distilled water in 300-ml Erlenmeyer flasks stoppered with metal caps and add 2 ml of a stock culture and 2 ml of the adjusted bacterial suspension for Entosiphon stock cultures. Store stock cultures at 25°C. Before inoculation control the flasks containing the stock cultures by means of an inverse microscope. Pretreatment of the bacteria used for feeding preliminary cultures of Entosiphon sulcatum does not differ from that of bacteria used for feeding the stock cultures. Keep preliminary cultures at 25°C over 72 h before using them for inoculation of the test cultures. Before inoculation control each flask containing the preliminary cultures by means of an inverse microscope. The toxicity threshold (TT) of test material was determined to be 236 mg/l for Entosiphon sulcatum. Therefore LOEC was considered to be 236 mg/l for 72h in Entosiphon sulcatum.

Thus on the basis of above both studies, toxicity of test chemical value ranges from 236 to 377 mg/l.

Thus based on the overall studies and results on fish, invertebrate and algae, chemical consider to be nontoxic and not classified as per the CLP classification criteria.