4,5-dihydroxy-1,3-dimethylimidazolidin-2-one

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

9/6/94 - 7/7/94

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Guideline study conducted in compliance with GLP regulations

Guideline:

other: OECD Guideline 301 A (new version) (Ready Biodegradability: DOC Die Away Test)

Principles of method if other than guideline:

Additional replicate run as part of the DOC die away test to determine the inhibition of the inoculum is used to assess the toxicity of the submission item towards microorganisms.

GLP compliance:

yes

Analytical monitoring:

yes

Test organisms (species):

activated sludge, domestic

Details on inoculum:

- Source of inoculum/activated sludge: Activated sludge from a laboratory wastewater treatment plants fed with municipal and synthetic sewage
- Concentration of sludge: 30 mg/L

Test type:

static

Total exposure duration:

28 d

Key result

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Conc. based on:

test mat.

Basis for effect:

other: microbial metabolism

Details on results:

Additional replicate run as part of the DOC die away test to determine the inhibition of the inoculum is used to assess the toxicity of the submission item towards microorganisms.
20 mg/L DOC of test material (corresponding to approx. 108 mg/L test substance) did not have any inhibitory effect on the activity of activated sludge.

Validity criteria fulfilled:

yes

Conclusions:

In a Ready Biodegradability: DOC Die Away Test according to OECD Guideline 301 A, the NOEC (28 d) was equal or higher than 100 mg/L.

Description of key information

NOEC (28 d) = approx. 100 mg/L (nominal, OECD 301A)

Key value for chemical safety assessment

EC10 or NOEC for microorganisms:

100 mg/L