Mentha citrata, ext.

Endpoint summary

Description of key information

Short- term toxicity to aquatic invertebrate:

Data available for the structurally and functionally similar read across chemicals has been reviewed todetermine the short term toxicity of aquatic toxicity of the test chemical Mentha citrata, ext. (85085 -49 -0).The studies are as mentioned below:

1.Short term toxicity test was performed according to OECD 202 for test chemical on Daphnia magna Straus 1820 was evaluated for 48 h

 >24 h old Daphnids were used as 5 per replicates and 4 replicates per treatment. The test was carried out in static without aeration in the dark; at 20±1°C in beakers covered with glass watches and containing 100 mL of reconstituted water of hardness 240 mg/L (CaCO3). The nominal concentrations subjected to the test were 10, 18, 32, 58 and 100 mg/L.

The effect concentration (EC50) of test chemical on Daphnia magna was observed to be 15 mg/l (95% CI: 13-17 mg/L).

Even though the above effect concentration is considered as toxic, but test material is readily degradable in aquatic environment . Hence, it is considered to be non toxic to aquatic invertebrate.

2.The test material was subjected to evaluate its efficiency for short term toxicity of aquatic invertebrates for 48 h according to OECD 202.

 Daphnia magna from CIBA-GEIGY's own testing facility culture were used for the test. Daphnids were inoculated in glass vessels containing approx. 2.5 l daphnid medium. Water was renewed 3 times weekly. At each renewal the daphnids were fed with a suspension of green algae (Scenedesmus subspicatus) supplemented by a suspension of Tetramin extract in such quantities that the feed is consumed within 24 h.

24 h before test begin reproductive daphnia are separated from the young by sieving through a 0.8-mm sieve.

 

For each concentration and for the control 20 daphnids were used, in 4 replicates of 5 daphnids each. During the exposure the daphnids were not fed.Glass beakers were filled with 100 ml daphnid medium that had been aerated for 24 h before the test and covered with watch glasses during the test. The temperature was kept at20 +/- 1 °C during the test, there was no lighting in the test room and no aeration of the vessels during the test.Stock solution.250 mg test material was dissolved in and made up with daphnid medium to 2000 ml.

 Nominal test concentrations were 100, 58, 32, 18 and 10 mg/l. Controls were blanks (daphnid medium only). EC50 values were calculated according to the maximum likelihood probit model

 Immobilisation after 24 h was found in 17/20 daphnids and after 48 h in 19/20 daphnids. The 48-h EC50 was calculated to be 59 mg/l(53-65 mg/l, 95% CL).

Even though the above effect concentration is considered as toxic, but test material is readily degradable in aquatic environment . Hence, it is considered to be non toxic to aquatic invertebrate.

Thus, based on the above summarised studies, Mentha citrata, ext and it’s structurally and functionallysimilar read across substance, it can be concluded that effect concetration value is in the range 15 - 49 mg/L. Thus, comparing this value with the criteria of CLP regulation, Mentha citrata, ext can be classified as " Acute aquatic 3" for short term toxicity for aquatic invertebrate .

Even though the above effect concentration is considered as toxic, but test material is readily degradable in aquatic environment . Hence, it is considered to be non toxic to aquatic invertebrate and can be categorize as "Not classified" as per CLP.

Toxicity to aquatic algae and cyanobacteria:

Data available for the structurally and functionally similar read across chemicals has been reviewed todetermine the short term toxicity of aquatic algae and cyanobacteria of the test chemical Mentha citrata, ext. (85085 -49 -0).The studies are as mentioned below:

1. The growth inhibition test of test chemical to green algae (Scenedesmus subspicatus) was evaluated for 72 h according to OECD 201.The algae were used as 3 replicates in treatment and 6 replicates in control with the initial cell density of 0.93 x 104 cells/mL.The test was conducted in 100 mL flasks containing 50 mL of algal medium; temperature: 23±1°C; continuous illumination (8000 lux).The nominal concentrations used in the medium were 4.4, 9.6, 21, 46 and 100 mg/L. The effect of test chemical on algae was observed under two parameter mean cell density (biomass) and inhibition % (growth rate

The EbC50 (biomass) was observed to be 16 mg/l and the ErC50 ( growth rate) was observed to be 62 mg/l.Even though the above effect concentration is considered as toxic, but test material is readily degradable in aquatic environment . Hence, it is considered to be non toxic to aquatic algae and cyanobacteria.

2.Test for determination of the inhibitory effect of substances in water on green algae Scenedesmus subspicatus was performed .

 The test material was emulsified in tween 80. Scendesmus subspicatus algae were exposed to aqueous dilutions of this emulsified test substance for 96 hours in quadruplicate.The nominal test concentrations were 0 (water controls), 10, 32, 100, 320 and 1000 mg/l.

 Cell densities were measured by chlorophyll fluorescence using impulse fluorometry in relative units, biomass and growth rates respectively the inhibition caused by the test substance were determined.

The effect concentration of test material on algal biomass was observed to be EbC50 = 88.3 mg/l and the effect concentration for growth rate of algae was ErC50 = 156.7 mg/l.

Thus, based on the above summarised studies, Mentha citrata, ext and it’s structurally and functionally similar read across substance, it can be concluded that effect concetration value is in the range 62 -156.7 mg/L. Thus, comparing this value with the criteria of CLP regulation, Mentha citrata, ext can be classified as " Acute aquatic 3" for short term toxicity for aquatic invertebrate .

Even though the above effect concentration is considered as toxic, but test material is readily degradable in aquatic environment . Hence, it is considered to be non toxic to aquatic invertebrate and can be categorize as "Not classified" as per CLP.

Additional information

Short- term toxicity to aquatic invertebrate:

Data available for the structurally and functionally similar read across chemicals has been reviewed todetermine the short term toxicity of aquatic toxicity of the test chemical Mentha citrata, ext. (85085 -49 -0).The studies are as mentioned below:

1.Short term toxicity test was performed according to OECD 202 for test chemical on Daphnia magna Straus 1820 was evaluated for 48 h

 >24 h old Daphnids were used as 5 per replicates and 4 replicates per treatment. The test was carried out in static without aeration in the dark; at 20±1°C in beakers covered with glass watches and containing 100 mL of reconstituted water of hardness 240 mg/L (CaCO3). The nominal concentrations subjected to the test were 10, 18, 32, 58 and 100 mg/L.

The effect concentration (EC50) of test chemical on Daphnia magna was observed to be 15 mg/l (95% CI: 13-17 mg/L).

Even though the above effect concentration is considered as toxic, but test material is readily degradable in aquatic environment . Hence, it is considered to be non toxic to aquatic invertebrate.

2.The test material was subjected to evaluate its efficiency for short term toxicity of aquatic invertebrates for 48 h according to OECD 202.

 Daphnia magna from CIBA-GEIGY's own testing facility culture were used for the test. Daphnids were inoculated in glass vessels containing approx. 2.5 l daphnid medium. Water was renewed 3 times weekly. At each renewal the daphnids were fed with a suspension of green algae (Scenedesmus subspicatus) supplemented by a suspension of Tetramin extract in such quantities that the feed is consumed within 24 h.

24 h before test begin reproductive daphnia are separated from the young by sieving through a 0.8-mm sieve.

 

For each concentration and for the control 20 daphnids were used, in 4 replicates of 5 daphnids each. During the exposure the daphnids were not fed.Glass beakers were filled with 100 ml daphnid medium that had been aerated for 24 h before the test and covered with watch glasses during the test. The temperature was kept at20 +/- 1 °C during the test, there was no lighting in the test room and no aeration of the vessels during the test.Stock solution.250 mg test material was dissolved in and made up with daphnid medium to 2000 ml.

 Nominal test concentrations were 100, 58, 32, 18 and 10 mg/l. Controls were blanks (daphnid medium only). EC50 values were calculated according to the maximum likelihood probit model

 Immobilisation after 24 h was found in 17/20 daphnids and after 48 h in 19/20 daphnids. The 48-h EC50 was calculated to be 59 mg/l(53-65 mg/l, 95% CL).

Even though the above effect concentration is considered as toxic, but test material is readily degradable in aquatic environment . Hence, it is considered to be non toxic to aquatic invertebrate.

Thus, based on the above summarised studies, Mentha citrata, ext and it’s structurally and functionallysimilar read across substance, it can be concluded that effect concetration value is in the range 15 - 49 mg/L. Thus, comparing this value with the criteria of CLP regulation, Mentha citrata, ext can be classified as " Acute aquatic 3" for short term toxicity for aquatic invertebrate .

Even though the above effect concentration is considered as toxic, but test material is readily degradable in aquatic environment . Hence, it is considered to be non toxic to aquatic invertebrate and can be categorize as "Not classified" as per CLP.

Toxicity to aquatic algae and cyanobacteria:

Data available for the structurally and functionally similar read across chemicals has been reviewed todetermine the short term toxicity of aquatic algae and cyanobacteria of the test chemical Mentha citrata, ext. (85085 -49 -0).The studies are as mentioned below:

1. The growth inhibition test of test chemical to green algae (Scenedesmus subspicatus) was evaluated for 72 h according to OECD 201.The algae were used as 3 replicates in treatment and 6 replicates in control with the initial cell density of 0.93 x 104 cells/mL.The test was conducted in 100 mL flasks containing 50 mL of algal medium; temperature: 23±1°C; continuous illumination (8000 lux).The nominal concentrations used in the medium were 4.4, 9.6, 21, 46 and 100 mg/L. The effect of test chemical on algae was observed under two parameter mean cell density (biomass) and inhibition % (growth rate

The EbC50 (biomass) was observed to be 16 mg/l and the ErC50 ( growth rate) was observed to be 62 mg/l.Even though the above effect concentration is considered as toxic, but test material is readily degradable in aquatic environment . Hence, it is considered to be non toxic to aquatic algae and cyanobacteria.

2.Test for determination of the inhibitory effect of substances in water on green algae Scenedesmus subspicatus was performed .

 The test material was emulsified in tween 80. Scendesmus subspicatus algae were exposed to aqueous dilutions of this emulsified test substance for 96 hours in quadruplicate.The nominal test concentrations were 0 (water controls), 10, 32, 100, 320 and 1000 mg/l.

 Cell densities were measured by chlorophyll fluorescence using impulse fluorometry in relative units, biomass and growth rates respectively the inhibition caused by the test substance were determined.

The effect concentration of test material on algal biomass was observed to be EbC50 = 88.3 mg/l and the effect concentration for growth rate of algae was ErC50 = 156.7 mg/l.

Thus, based on the above summarised studies, Mentha citrata, ext and it’s structurally and functionally similar read across substance, it can be concluded that effect concetration value is in the range 62 -156.7 mg/L. Thus, comparing this value with the criteria of CLP regulation, Mentha citrata, ext can be classified as " Acute aquatic 3" for short term toxicity for aquatic invertebrate .

Even though the above effect concentration is considered as toxic, but test material is readily degradable in aquatic environment . Hence, it is considered to be non toxic to aquatic invertebrate and can be categorize as "Not classified" as per CLP.