Mentha citrata, ext.

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Remarks:

of read across substance

Justification for type of information:

Data for the target chemical is summarized based on the structurally similar read across chemicals

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

other: as mentioned below

Principles of method if other than guideline:

WoE report is based on two short term toxicity study of fish for the test chemical :
1.To evaluate short term aquatic toxicity of test material on Scenedesmus subspicatus.
2.To evaluate toxicity of test material on Scenedesmus subspicatus

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material : Mentha citrata, ext.
- IUPAC name : Mentha citrata, ext.
- Molecular formula : C10H18O (Linalool) or C12H20O2 (Linalyl acetate)
- Molecular weight : 154.251- 196.288 g/mol
- Substance type: Organic
- Physical state: Clear liquid (Colorless to pale yellow)

Analytical monitoring:

yes

Remarks:

1.At 0 and 72 h from all concentrations (composite sample of replicates) by extraction/GC-MS.

Vehicle:

yes

Remarks:

2. test material was emulsified using Tween80

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Test type:

static

Water media type:

freshwater

Total exposure duration:

96 h

Post exposure observation period:

24, 48 and 72 h

Test temperature:

1.23±1°C

pH:

1.7.7-9.0

Nominal and measured concentrations:

1) 4.4, 9.6, 21, 46 and 100 mg/L
2) 0 (water controls), 10, 32, 100, 320 and 1000 mg/l

Details on test conditions:

1.- Test vessel: flasks
- fill volume: 100 mL flasks containing 50 mL of algal medium
- Initial cells density: 0.93 x 104 cells/mL.
- No. of vessels per concentration (replicates): 3 per treatment,
- No. of vessels per control (replicates): 6 for controls
-Light intensity : continuous illumination (8000 lux).

2.- Test material was emulsified using Tween80
- Cell densities were measured by
chlorophyll fluorescence using impulse fluorometry in relative units.
- Scendesmus subspicatus algae were exposed to aqueous dilutions of this emulsified test substance for
96 hours in quadruplicate.

Reference substance (positive control):

not specified

Duration:

72 h

Dose descriptor:

other: EbC50

Effect conc.:

16 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: Read across 1

Duration:

72 h

Dose descriptor:

other: ErC50

Effect conc.:

62 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: Read across 1

Duration:

96 h

Dose descriptor:

other: EbC50

Effect conc.:

88.3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: Read across 2

Duration:

96 h

Dose descriptor:

other: ErC50

Effect conc.:

156.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: Read across 2

Details on results:

1.EC50 was alculated by Logit model

Validity criteria fulfilled:

not specified

Conclusions:

The test chemical Mentha citrata, ext. is likely to be toxic to aquatic algae and cynobacteria in the dose range of 62 - 156.7 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.

Executive summary:

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.

Description of key information

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.

Key value for chemical safety assessment

EC50 for freshwater algae:

156 mg/L

Additional information

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 .