Ethyl N-hydroxyacetimidate

Endpoint summary

Description of key information

Short term toxicity to aquatic invertebrates:

Based on the prediction done using the OECD QSAR toolbox version 3.4 with log kow as the primary descriptor and considering the seven closest read across substances, toxicity on Daphnia magna predicted for (E)-(ethyl N-hydroxyethenecarboximidate) (10576-12-2).The EC50 value was estimated to be 729.034 mg/l when (E)-(ethyl N-hydroxyethenecarboximidate) exposed to Daphnia magna for 48 hrs. 

 

Toxicity to aquatic algae and cyanobacteria:

Based on the prediction done using the OECD QSAR toolbox version 3.4 with log kow as the primary descriptor and considering the five closest read across substances, toxicity on Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) was predicted for (E)-(ethyl N-hydroxyethenecarboximidate) (10576-12-2).The EC50 value was estimated to be 296.405 mg/l when (E)-(ethyl N-hydroxyethenecarboximidate) exposed to Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) for 72hrs. 

Additional information

Summarized result of toxicity of (E)-(ethyl N-hydroxyethenecarboximidate) (10576-12-2) on the growth and other activity of aquatic invertebrates, algae and cyanobacteria by considering the data for target as well as RA chemical which was selected on the basis of structure similarity are as follows:

 

Short term toxicity to aquatic invertebrates:

Based on the various experimental data and prediction data for the target chemical study have been reviewed to determine the toxic nature of (E)-(ethyl N-hydroxyethenecarboximidate) (10576-12-2) on the growth of invertebrates. The studies are as mentioned below:

In the first predicted study for the target chemical (E)-(ethyl N-hydroxyethenecarboximidate) (10576-12-2) from QSAR toolbox 2017, study was carried out. Based on the prediction done using the OECD QSAR toolbox version 3.4 with log kow as the primary descriptor and considering the seven closest read across substances, toxicity on Daphnia magna predicted for (E)-(ethyl N-hydroxyethenecarboximidate) (10576-12-2).The EC50 value was estimated to be 729.034 mg/l when (E)-(ethyl N-hydroxyethenecarboximidate) exposed to Daphnia magna for 48 hrs. 

 

In second predicted study for the target chemical (E)-(ethyl N-hydroxyethenecarboximidate) (10576-12-2) based on the prediction done by EPI suite, ECOSAR version 1.1, on the basis of similarity of structure to chemicals for which the aquatic toxicity has been previously measured by structure-activity relationships (SARs) program, the LC 50 value for short term toxicity to aquatic invertebrates was predicted. On the basis of this program, the LC 50 value for short term toxicity to aquatic invertebrates was predicted to be 1055.510 mg/l for (E)-(ethyl N-hydroxyethenecarboximidate) in 48 hrs. Based on this value it can be concluded that the substance (E)-(ethyl N-hydroxyethenecarboximidate) is considered to be not toxic to aquatic environment and cannot be classified as per the criteria mentioned in CLP regulation.

 

Similarly in the third weight of evidence study for the second RA chemical 1,1-dimethyl propyl methyl ether (TAME) (994-05-8) (from Chemosphere, 1997) toxicity was measured. Study was conducted to determine the toxic nature of chemical 1,1-dimethyl propyl methyl ether (TAME) on the growth and mobility of daphnia magna. Test was conducted according to the standard test guideline 202. Immobility of daphnia magna was determined over a 48 h exposure period. Nominal 0.1, 1, 10 and 100 mg/l concentrations of TAME and a control (dilution water) were prepared. Completely filled, sealed flasks were used to prevent volatile losses of TAME. The highest exposure concentration (nominal 100 mg/l) was analysed by gas chromatography at the beginning and end of the exposure period. 20 Daphnia magna were placed in 4 flasks at 100 mg/l and the control level, and 10 D. magna were placed in 2 flask for the remaining treatment levels. Based on the immobility of daphnia magna due to the exposure of chemical 1,1-dimethyl propyl methyl ether (TAME), the EC50 was determine to be > 100 mg/l.

 

Similarly fourth weight of evidence study was conducted for the RA chemical (556-88-7) from ECTOX database, 2017. Study was conducted to determine the toxic nature of chemical 1-nitroguanidine on the growth of invertebrates (Ceriodaphnia dubia). Test was conducted in the static system for the total exposure period of 48hrs. <12 h old Neonate was used in the test as attest organism by providing proper conditions of temperature and pH. After the 48hrs of exposure lethal concentration to 50% of test organisms was detected. Based on the mortality of Ceriodaphnia dubia (Water Flea) due to the exposure of chemical 1-nitroguanidine for 48hrs, the LC50 was 2698 mg/l. Thus on the basis of LC50, chemical can be concluded as nontoxic.

 

Based on the data obtain from various predicted and experimental studies for the toxicity on invertebrates due to the exposure of (E)-(ethyl N-hydroxyethenecarboximidate) (10576-12-2) it was concluded that the chemical (E)-(ethyl N-hydroxyethenecarboximidate) was consider as nontoxic and can be consider to be not classified as toxic to aquatic invertebrates as per CLP classification criteria.

 

 

Toxicity to aquatic algae and cyanobacteria:

Based on the various experimental data and prediction data for the target chemical study have been reviewed to determine the toxic nature of (E)-(ethyl N-hydroxyethenecarboximidate) (10576-12-2) on the growth of algae. The studies are as mentioned below:

In the first predicted study for the target chemical (E)-(ethyl N-hydroxyethenecarboximidate) (10576-12-2) from QSAR toolbox 2017, study was carried out. Based on the prediction done using the OECD QSAR toolbox version 3.4 with log kow as the primary descriptor and considering the five closest read across substances, toxicity on Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) was predicted for (E)-(ethyl N-hydroxyethenecarboximidate) (10576-12-2).The EC50 value was estimated to be 296.405 mg/l when (E)-(ethyl N-hydroxyethenecarboximidate) exposed to Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) for 72hrs. 

 

In second predicted study for the target chemical (E)-(ethyl N-hydroxyethenecarboximidate) (10576-12-2) based on the prediction done by EPI suite ECOSAR version 1.10, the short term toxicity on green algae was predicted for test substance (E)-(ethyl N-hydroxyethenecarboximidate) (10576 -12 -2). On the basis of effects observed in a static freshwater system, the effect concentration EC50 value for the substance is estimated to be 432.880 mg/l for green algae for 72 hrs duration. Based on this value, it can be concluded that the test chemical (E)-(ethyl N-hydroxyethenecarboximidate) can be considered as non-toxic to green algae at environmentally relevant concentrations and can be considered not-classified as per the CLP classification criteria. 

 

Similarly in the third weight of evidence study for the second RA chemical 1,1-dimethyl propyl methyl ether (TAME) (994-05-8) (from Chemosphere, 1997) toxicity was measured. Study was conducted to determine the toxic nature of chemical 1,1-dimethyl propyl methyl ether (TAME) on the growth of algae Selenastrum capricornutum. Test was conducted according to the standard test guideline 201. Growth inhibition of liquid cultures of Selenastrum capricornutum (green alga) was determined over a 72 h exposure period. Nominal test concentrations were 0, 6.25, 12.5, 25, 50 and 100 mg/l. completely filled, sealed flasks were used to prevent volatile losses of TAME. The initial inoculum concentration was 1 x 10⁴cells/ml. Nominal concentrations were confirmed by gas chromatography at the beginning and end of the exposure period. The cell concentration in the stock cultures were determined by an electronic cell counter. After the exposure of chemical, EC50 was measured based on the average specific growth rate and area under the growth curves. The NOEC levels were determined to exceed 100 mg/l (p = 0.05). Based on the growth inhibition of Selenastrum capricornutum (green alga) due to the exposure of chemical 1,1-dimethyl propyl methyl ether (TAME), the EbC50 and ErC50 was > 100 mg/l based on the area under the growth curves and average specific growth rate.  

 

Similarly in the fourth weight of evidence study for the read across chemical (111-76-2) from j-check, 2017, Study was conducted for determination of nature of chemical 1-Butoxy-2-hydroxyethan on the growth and other activity of test animal green algae. Test performed under the static system for the total exposure period of 72hrs. After the exposure of chemical 1-Butoxy-2-hydroxyethan, effect concentration was measured at which 50% growth inhibited by the chemical. Based on the growth rate inhibition of green algae, the EC50 and NOEC was > 1000 and 130 MG/L. And on the basis of area under the growth curve and biomass rate the EC50 and NOEC was 630 mg/l and 63 mg/l. Thus the chemical was concluded as nontoxic and can be consider to be not classified as per the CLP classification criteria.

 

 

Based on the data obtain from various predicted and experimental studies for the toxicity on invertebrates due to the exposure of (E)-(ethyl N-hydroxyethenecarboximidate) (10576-12-2) it was concluded that the chemical (E)-(ethyl N-hydroxyethenecarboximidate) was consider as nontoxic and can be consider to be not classified as toxic to aquatic algae as per CLP classification criteria.

 

Based on the data obtain from various sources for evaluating the toxicity of target chemical (E)-(ethyl N-hydroxyethenecarboximidate) (10576-12-2), on the invertebrates, algal growth, it can be concluded that the substance for (E)-(ethyl N-hydroxyethenecarboximidate) (10576-12-2) is considered to be nontoxic and can be consider to be not classified as toxic to aquatic environment as per CLP classification criteria.