Methyl anthranilate

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from peer reviewed journal

Qualifier:

according to guideline

Guideline:

other: as mentioned below

Principles of method if other than guideline:

Determination of toxicity of test chemical to aquatic algae

GLP compliance:

not specified

Analytical monitoring:

not specified

Vehicle:

yes

Remarks:

methanol

Test organisms (species):

other: 1. Oscillatoria perornata 2. Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)

Test type:

static

Water media type:

freshwater

Total exposure duration:

5 d

Test temperature:

28-30°C

Details on test conditions:

-Resuseable fused silica, 96-well microplates were used.
-Microplates were placed in a Percival Scientific model I - 36LL growth chamber at 28-30°C which were illuminated by overhead fluorescent lamps (20W) at light intensity of 18-24 µE/m2/sec.
-Packard model Spectra Count microplate photometer was used to measure optical densities of each well at 24h intervals for 5 days at 650nm.

Reference substance (positive control):

not specified

Key result

Duration:

5 d

Dose descriptor:

LOEC

Effect conc.:

151.16 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Details on results:

The Lowest-Complete-Inhibition Concentration of test chemical on both the species i.e., Oscillatoria perornata and Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) was determined to be 1000 µM.

Validity criteria fulfilled:

not specified

Conclusions:

The LOEC value of test chemical was determined to be 151.16 mg/L after exposure of test chemical toOscillatoria perornata and Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum for 5 days. On the basis of LOEC value the EC50 value was determined to be >151.16 mg/L.By considering this EC50 value it is concluded that test chemical is nontoxic to aquatic algae and cannot be classified according to CLP regulation.

Executive summary:

An experiment was conducted to determine the short term toxicity of test chemical to aquatic alagae. The test organism used in this study were Oscillatoria perornata and Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum. Test chemical solution was prepared by using Methanol was used as a solvent. The experiment was conducted in static system and test chemical was exposed to algae for 5 days. The 96-well microplates were used which were placed in a growth chamber at 28-30°C. Hence, after 5 days of exposure the LOEC value of test chemical was determined to be 151.16 mg/L on the basis of this the EC50 value was determined >151.16 mg/L. By considering this EC50 value it is concluded that test chemical is nontoxic to aquatic algae and cannot be classified according to CLP regulation.

Description of key information

An experiment was conducted to determine the short term toxicity of test chemical to aquatic alagae. The test organism used in this study were Oscillatoria perornata and Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum. Test chemical solution was prepared by using Methanol was used as a solvent. The experiment was conducted in static system and test chemical was exposed to algae for 5 days. The 96-well microplates were used which were placed in a growth chamber at 28-30°C. Hence, after 5 days of exposure the LOEC value of test chemical was determined to be 151.16 mg/L on the basis of this the EC50 value was determined >151.16 mg/L. By considering this EC50 value it is concluded that test chemical is nontoxic to aquatic algae and cannot be classified according to CLP regulation.

Key value for chemical safety assessment

EC50 for freshwater algae:

151.16 mg/L

Additional information

Various experimental studies have been reviewed from different sources for target chemical and its structurally similar read across chemical to determine the short term toxicity of test chemical to aquatic algae and their results are summarized below.

The first experimental study was reviewed from journal Bull. Environ. Contam. Toxicol. (2001)in this an experiment was conducted to determine the short term toxicity of test chemical to aquatic alagae. The test organism used in this study were Oscillatoria perornata and Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum. Test chemical solution was prepared by using Methanol was used as a solvent. The experiment was conducted in static system and test chemical was exposed to algae for 5 days. The 96-well microplates were used which were placed in a growth chamber at 28-30°C. Hence, after 5 days of exposure the LOEC value of test chemical was determined to be 151.16 mg/L on the basis of this the EC50 value was determined to be >151.16 mg/L. By considering this EC50 value it is concluded that test chemical is nontoxic to aquatic algae and cannot be classified according to CLP regulation.

 

In next study an experiment was conducted to determine the toxicity of test chemical to aquatic algae according to OECD Guideline 201 (Alga, Growth Inhibition Test). The test organism used in this study was Desmodesmus subspicatus (previous name: Scenedesmus subspicatus).The stock solution was prepared by dissolving test chemical in acetone of 200 mg/L. Test solutions of required concentrations were prepared by mixing the stock solution of the test chemical with OECD growth medium inoculum culture. The nominal concentrations of test chemical used in the study were 3.8, 4.7, 9.0, 11.3, 90.1 mg/l. 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 nonlinear regression by the software Prism 4.0. Effect on the growth of algae was determine after an exposure period of 72 hrs.

The median effective concentration (EC50) for the test chemical, in algae was determined to be 111.7 mg/L on the basis of growth rate inhibition effects in a 72 hour study. Based on the EC50 value, which indicates that the substance is likely to be non-hazardous to aquatic algae and cannot be classified as per the CLP classification criteria.

 

 

In last study an experiment was conducted to determine the toxicity of test chemical to aquatic algae according to OECD Guideline 201 (Alga, Growth Inhibition Test). The test organism used in this study was Desmodesmus subspicatus (previous name: Scenedesmus subspicatus). The experiment was conducted in static system using freshwater. Based on the effect on growth rate of the test organism and after exposure of test chemical to aquatic algae the EC50 value was determined to be 110 mg/l. By considering EC50 value it is concluded that the test chemical is non-toxic to aquatic organisms and cannot be classified as hazardous as per the CLP criteria.

By considering results of all the studies mentioned above the EC 50 value of test chemical was determined to be in range from 110 mg/L to >151.16 mg/L. By considering this range EC50 value it is concluded that the test chemical is non-toxic to aquatic organisms and cannot be classified as hazardous as per the CLP criteria.