[ethylenebis[nitrilobis(methylene)]]tetrakisphosphonic acid, calcium sodium salt

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

weight of evidence

Study period:

1984

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to the appropriate OECD test guideline, and in compliance with GLP.

Data source

Reference

Reference Type:

other: Study report

Title:

Unnamed

Year:

1984

Report date:

1984

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 E (Ready biodegradability: Modified OECD Screening Test)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

[ethylenebis[nitrilobis(methylene)]]tetrakisphosphonic acid, sodium salt

EC Number:

244-742-5

EC Name:

[ethylenebis[nitrilobis(methylene)]]tetrakisphosphonic acid, sodium salt

Cas Number:

22036-77-7

IUPAC Name:

22036-77-7

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

Activated sludge from the HRC sewage treatment plant. The nature of the influent to this treatment plant is not known.

The activated sludge was filtered through Whatman No 1 paper (first 200 ml discarded) and the filtrate was kept aerated until used. 

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

40 other: mg C/l

Based on:

DOC

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

DOC removal

Reference substance

Reference substance:

benzoic acid, sodium salt

Results and discussion

% Degradation

Parameter:

% degradation (DOC removal)

Value:

0

Sampling time:

21 d

Remarks on result:

other: Data for days 27-28 of the test period were not recorded due to contamination by a broken pipe.

Details on results:

Briquest 422-25S attained 0% degradation after 21 days and was not considered readily biodegradable under OECD
Guideline No. 301-E. The control substance attained 85% degradation after 14 days and 97% after 28 days, confirming
suitability of the inoculum and culture conditions.

Degradation products: no

BOD5 / COD results

Results with reference substance:

Day 7: 79%
Day 14: 85%
Day 28: 97%

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed