2,5-xylidine

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:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Authoritative datbase

Justification for type of information:

Data is from authoritative database

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Principles of method if other than guideline:

Determination of short-term toxicity to aquatic algae according to OECD Guideline 201 (Alga, Growth Inhibition Test) for 72 h in a static system.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

other: Green algae

Test type:

static

Water media type:

freshwater

Total exposure duration:

72 h

Reference substance (positive control):

no

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

30 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: Other details not known

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Validity criteria fulfilled:

no

Conclusions:

Short-term toxicity of the test chemical on aquatic algae was concluded by observing the effects on the growth of algae and the EC50 value was observed to be at 30 mg/L.Whereas, NOEC was determined at 2.0 mg/L

Executive summary:

Study was conducted according to OECD Guideline 201 (Alga, Growth Inhibition Test) for determining toxicity of the test chemical on aquatic alga in a static medium. After 72 h of study, effective concentration was determined to be at 30 mg/L on the basis of growth rate inhibition, while NOEC was determined at 2.0 mg/L. Based on the EC50 value, the test chemical is consider to be toxic and can be consider to be classified under aquatic chronic 3 category as per the CLP classification criteria.

Description of key information

Study was conducted to assess the effect of test chemical on the growth rate of green alga. Test was conducted according to OECD Guideline 201 (Alga, Growth Inhibition Test) for determining toxicity of the test chemical on aquatic alga in a static medium. After 72 h of study, effective concentration was determined to be at 30 mg/L on the basis of growth rate inhibition, while NOEC was determined at 2.0 mg/L. Based on the EC50 value, the test chemical is consider to be toxic and can be consider to be classified under aquatic chronic 3 category as per the CLP classification criteria.

Key value for chemical safety assessment

EC50 for freshwater algae:

30 mg/L

Additional information

Based on the experimental data, toxicity of test chemical was determined on the basis of growth rate of aquatic algae. The studies are summarized as below:

First study was conducted to assess the effect of test chemical on the growth rate of green alga. Test was conducted according to OECD Guideline 201 (Alga, Growth Inhibition Test) for determining toxicity of the test chemical on aquatic alga in a static medium. After 72 h of study, effective concentration was determined to be at 30 mg/L on the basis of growth rate inhibition, while NOEC was determined at 2.0 mg/L. Based on the EC50 value, the test chemical is consider to be toxic and can be consider to be classified under aquatic chronic 3 category as per the CLP classification criteria.

First experimental study for the test chemical was further supported by second experimental study from secondary source.

Aim of second study was to determine the effect of test chemical on aquatic algae. After the exposure, LC50 value was determined to be 44mg/l. Based on the above value, the chemical is considered to be toxic and can be classified under aquatic chronic 3 category.

Again third study was conducted for testing the toxicity of test chemical on aquatic algae.

Aim of third experiment was to determine the toxicity of the test chemical on the algal species (Tetrahymena pyriformis). After 48 hours of exposure, effective concentration (EC50) was determined to be268 mg/L. Hence, based on the above value chemical is considered to be not classified.

Thus, based on the maximum experimental values, it can be concluded that the chemical is toxic can be classified under aquatic chronic 3 category.