N,N'-[(methylimino)dipropane-1,3-diyl]dioleamide

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:

key study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
Refer to attached document

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 0.1 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr. (dissolved fraction)

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

>= 0.1 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr. (dissolved fraction)

Basis for effect:

growth rate

Conclusions:

N, N’-[(methylimino)bis (trimethylene)]bis(oleamide) caused no effects on growth rate of freshwater green algae up to the limit of solubility based on information from the related read-across substance N,N’[(methylimino)bis(trimethylene)]bis(stearamide).

Description of key information

N, N’-[(methylimino)bis (trimethylene)]bis(oleamide) caused no effects on growth rate of freshwater green algae up to the limit of solubility based on information from the related read-across substance N,N’[(methylimino)bis(trimethylene)]bis(stearamide). 

Key value for chemical safety assessment

EC50 for freshwater algae:

0.1 mg/L

EC10 or NOEC for freshwater algae:

0.1 mg/L

Additional information

Available information from an OECD 201 guideline study with the test substance N,N’[(methylimino)bis(trimethylene)]bis(stearamide) were used to evaluate short-term toxicity to aquatic algae and cyanobacteria of N, N’-[(methylimino)bis(trimethylene)]bis(oleamide).

 

The toxicity of N,N’-[(methylimino)bis(trimethylene)]bis(stearamide)to the unicellular freshwater green alga Pseudokirchneriella subcapitata was determined according to the principles of OECD 201 andCouncil Regulation (EC) No. 266/2016/Method C.3.The aim of the study was the determination of NOEC, LOEC, EC₁₀- , EC₂₀- and EC₅₀-values of growth rate and yield over a period of 72 hours.

The study was conducted under static conditions with an initial cell density of 5523 cells/mL. For preparation of the test concentration ofN,N’-[(methylimino)bis(trimethylene)]bis(stearamide)a stock solution was prepared in THF+0.1% formic acid (solvent). The stock solution was treated with ultrasound for 60 minutes at room temperature.The test concentration was prepared by adding 0.1 mL/L of the appropriate stock solutions to thedilution water.

Sixreplicates were used for thelimit concentration,the control and solvent control.

The environmental conditionswere within the acceptable limits.

 

The test media were visually clear throughout the test period. The concentrations of thetest item N,N’-[(methylimino)bis(trimethylene)]bis(stearamide) were analytically verified via LC-MS/MS at the start of the exposure (0 hours) and at the end of the exposure (72 hours) in the limit concentration, the solvent control and control.

The measured concentration in the limit concentration was 106% at the start of the exposure (0 hours) and 37% at the end of the exposure (72 hours), representing 35% of the initially measured test item concentration.

Since the limit of solubility of the test item in test medium under test conditions is considered to be 0.1 mg/L and the initially measured concentration was inside the nominal range, all effect values given are based on the nominal test item concentration of N,N’-[(methylimino)bis(trimethylene)]bis(stearamide).

No effects on growth rate were observedup to the limit of solubility of the test item in the test medium and under the test conditions.

 

NOEC 72 hr.: ≥ 0.100 mg/L

ErC10 72 hr.: > 0.100 mg/L

ErC20 72 hr.: > 0.100 mg/L

ErC50 72 hr.: > 0.100 mg/L

 

The study meets the validity criteria of the guideline.