1,6-dichloro-1,6-dideoxy-β-D-fructofuranosyl 4-chloro-4-deoxy-α-D-galactose

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

toxicity to microorganisms, other

Remarks:

in sewage treatment

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1984-08-14

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

Version / remarks:

version 1984

GLP compliance:

yes

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 167002
- Purity test date: 97.7%

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: in the dark at 4°C

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: a 2.0 g/L solution of test item was prepared in distilled waterPREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Controls: a 0.5 g/L solution of 3,5 dichlorophenol was prepared in distilled water

Test organisms (species):

activated sludge, domestic

Details on inoculum:

- Name and location of sewage treatment plant where inoculum was collected: Buckland Sewage Treatmant Works, Newton Abbot, Devon, UK
- Preparation of inoculum for exposure: three days aeration at 22 +/- 3°C, fed twice with synthetic sewage (16 g peptone, 11 g meat extract, 3 g urea, 0.7 g NaCl, 0.4 g CaCl2*2 H2O, 0.2 g MgSO4*7 H2O, 2.8 g K2HPO4 per 1 L tap water)
- Initial biomass concentration: 4080 mg/L (total filterable solids concentration)

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

3 h

Test temperature:

22 +/- 3°C

pH:

7.5 - 7.8

Nominal and measured concentrations:

nominal: 10, 18, 32, 100, 180, 320 mg test item/L

Details on test conditions:

TEST SYSTEM
- Aeration: 0.5 - 1 Liter per minute using a pasteur pipette
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 2
- Sludge concentration (weight of dry solids per volume): 1632mg/L
- Nutrients provided for bacteria: synthetic sewage
TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: tap water and distilled water
EFFECT PARAMETERS MEASURED: respiration rate as mg O2/L_h

Reference substance (positive control):

yes

Remarks:

3,5 dichlorophenol

Key result

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

Duration:

3 h

Dose descriptor:

EC10

Effect conc.:

> 320 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Details on results:

- Blank controls oxygen uptake rate: 31.25 mg O2/L_h = 19.5 mg 02/g_h activated sludge

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Relevant effect levels: EC50 around 7.8 mg/L

Validity criteria fulfilled:

yes

Conclusions:

No significant inhibition of respiration was observed at the highest test item concentration tested (320 mg/L nominal) and therefore it is concluded that the test item is unlikely to be toxic to aerobic sewage treatment processes.

Description of key information

No significant inhibition of the microbial activity up to a substance concentration of 320 mg/L in a biodegradation tests according to OECD 209 were observed. Therefore, no further test is necessary to evaluate the respiration inhibition of activated sludge.

Key value for chemical safety assessment

EC50 for microorganisms:

320 mg/L

EC10 or NOEC for microorganisms:

100 mg/L