5-thiazolylmethanol

Toxicity to microorganisms

Administrative data

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02 February 1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: done under GLP and OECD method

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: EC Directive 87/302 'Activated Sludge, Respiration Inhibition test'

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

5-thiazolylmethanol

EC Number:

414-780-9

EC Name:

5-thiazolylmethanol

Cas Number:

38585-74-9

Molecular formula:

C4H5NOS

IUPAC Name:

(1,3-thiazol-5-yl)methanol

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

Test substance concentration: 100 mg/L
Reference substance concentration: 3.2, 10 and 32 mg/ml

Test organisms

Test organisms (species):

activated sludge of a predominantly domestic sewage

Details on inoculum:

Activated sewage sludge maintained at 20±2°C, continuously aerated and fed 50ml/l of synthetic sewage per day prior to use.

Study design

Test type:

other: aerated at 0.5 - 1.0L/min with compressed air via an airstone.

Limit test:

yes

Total exposure duration:

3 h

Test conditions

Hardness:

approx 120 -180mg/L (as CaCO3)

Test temperature:

21°C

pH:

7.8

Dissolved oxygen:

6.5 - 2.5mgO2/L

Details on test conditions:

TEST SYSTEM: series
- Test vessel: 1 liter glass flask
- Aeration: yes
- No. of vessels per concentration (replicates): not stated
- No. of vessels per control (replicates): not stated
- No. of vessels per vehicle control (replicates): Not stated

test has test substance+synthetic sewage + inoculum
controls has synthetic sewage + inoculumn only

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: dechlorinated and Reverse Osmosis

TEST CONCENTRATIONS
Test substance concentration: 100 mg/L
Reference substance concentration: 3.2, 10 and 32 mg/ml

Reference substance (positive control):

yes

Remarks:

3.5 dichlorophenyl

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Effect concentrations 2

Duration:

3 h

Dose descriptor:

NOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Details on results:

100mg/l was the highest concentration used as it was considered unecessary to test in excess of this level.

Results with reference substance (positive control):

EC50 (3 hours): 25mg/l

Reported statistics and error estimates:

Variation in respiration rates of Controls 1 and 2: ±8%

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

(i) Respiration rate for the 2 controls cultures: within 15% of each other at 3 hrs contact time. (ii) EC50 of 3,5-dichlorophenol at 3 hours contact time: 5 - 30mg/L

Conclusions:

The EC50 (respiration inhibition) values for A-87440.0 with activated sewage sludge has been determined as >100mg/L for the 3 hour contact time.