Amides, coco, N,N-bis(hydroxyethyl); C10-12 and C18-unsatd. DEA

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

toxicity to microorganisms

Type of information:

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

Adequacy of study:

key study

Study period:

Not reported

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Justification for type of information:

Refer to section 13 for details on the read-across justification. The study with the read across substance is considered sufficient to fulfil the information requirements as further explained in the provided endpoint summary.

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

DIN 38412-8 (Pseudomonas Zellvermehrungshemmtest)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

Maximal soluble amount of test material (saturation concentration) diluted in doubly distilled water. Test concentrations prepared by serial dilution of initial saturated solution.

Test organisms (species):

Pseudomonas putida

Details on inoculum:

Pseudomonas putida MIGULA, strain Berlin 33/2, from the German Microorganism culture Collection (D-3300 Braunschweig)

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

16 h

Test temperature:

25 ±1 °C

Nominal and measured concentrations:

Nominal: 0.01, 0.05, 0.10, 0.50, 1.00, 2.50, 5.00 and 10.00 g/L

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

6 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth inhibition

Key result

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

830 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth inhibition

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the study, the EC50 and EC10 were 6.0 and 0.83 g/L (i.e. 6000 and 830 mg/L), respectively.

Executive summary:

A study was conducted to assess the toxicity of the read across substance, C8-18 and C18-unsatd. DEA to the bacteria Pseudomonas putida according to DIN Guideline 38412 L8, in compliance with GLP. Pseudomonas putida colonies, in triplicate, were exposed to the test substance at nominal concentrations of 0.01, 0.05, 0.10, 0.50, 1.00, 2.50, 5.00 and 10.00 g/L. Inhibition of cell growth compared to controls was recorded after 72 h. Under the conditions of the study, the EC50 and EC10 were 6.0 and 0.83 g/L (i.e. 6000 and 830 mg/L), respectively (Poth, 1992). Based on the results of the read across study, similar EC50 values are considered for the test substance, C10 -12 and C18 -unsatd. DEA.

Description of key information

Based on the results of the read across study, the EC50 and EC10 values of the test substance, C10-12 and C18-unsatd. DEA, for toxicity to microorganisms were determined to be 6000 mg/l and 830 mg/L (nominal) respectively.

Key value for chemical safety assessment

EC50 for microorganisms:

6 000 mg/L

EC10 or NOEC for microorganisms:

830 mg/L

Additional information

A study was conducted to assess the toxicity of the read across substance, C8-18 and C18-unsatd. DEA to the bacteria Pseudomonas putida according to DIN Guideline 38412 L8, in compliance with GLP. Pseudomonas putida colonies, in triplicate, were exposed to the test substance at nominal concentrations of 0.01, 0.05, 0.10, 0.50, 1.00, 2.50, 5.00 and 10.00 g/L. Inhibition of cell growth compared to controls was recorded after 72 h. Under the conditions of the study, the EC50 and EC10 were 6.0 and 0.83 g/L (i.e. 6000 and 830 mg/L), respectively (Poth, 1992). Based on the results of the read across study, similar EC50 values are considered for the test substance, C10 -12 and C18 -unsatd. DEA.