Potassium sodium tartrate

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

8 - 22 July 1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Official and peer reviewed source. Published by the Japanese Official Bulletin of the Ministry of International Trade and Industry (former MITI) and currentl accesible via de biodegradation database of the Japanese National Institute of Technology and Evaluation.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1994

Report Date:

1994

Materials and methods

Test guideline

Qualifier:

according to

Guideline:

OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I))

Deviations:

no

GLP compliance:

yes

Test material

Reference

Name:

Unnamed

Type:

Constituent

Details on test material:

Anhydrous disodium tartate used as test substance (CAS: 868-18-8). Referred to as K-1129 in the report, with a mol wt of 194.05 and a reported purity of 99.8%. Batch tested reported as M3R8322. Original report available only in Japanese.

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

Concentration of activated sludge: 30 mg/L Cultivation conditions reported as regular. Aerobic conditions maintaine in a closed system.
Innoculum obtained from 10 samples obtained from waste water treatment plants in: Fushiko River plant (Sapporo-shi, Hokkaido), Nakahama plant (Osaka-shi, Osaka), Kitakami River (Ishinomaki-shi, Miyagi), Yoshinogawa (Tokushima-shi, Tokushima), Gulf of Hiroshima (Hiroshima-shi, Hiroshima), Fukashiba plant (Fashima-gun, Ibaraki), Ochiai plant (Shinjuku-ku, Tokyo), The Shinano River (Nishikanbara-gun, Niigata), Lake Biwa-ko (Ootsu-shi, Shiga), Gulf of sinus Sea (Kitakyuushuu-shi, Fukuoka).
Inoculum mixed and prefiltered. Glucose / peptone medium used for cultivation. Dissoolved oxygen, pH and temperature of sludge culture is measured during culture and subjected to microscoic examination for abnormalities. None were detected.

Duration of test (contact time):

14 d

Initial test substance concentration

Initial conc.:

100 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation 1

Parameter followed for biodegradation estimation:

O2 consumption

Parameter followed for biodegradation estimation 2

Parameter followed for biodegradation estimation:

TOC removal

Parameter followed for biodegradation estimation 3

Parameter followed for biodegradation estimation:

test mat. analysis

Remarks:

HPLC

Details on study design:

Test substance concentration = 100 mg/L. Test performed in triplicate test vessels at a temperature of 25 ±1 C°.
Water + test substance as well as a control blank were included in the experimental design. Test substance reported as stable under storage conditions.

Reference substance

Reference substance:

aniline

Remarks:

Batch number 2823. Reagent grade. Manufactured by Showa chemicals.

Results and discussion

Test performance:

Degradation of reference substance, expressed in terms of BOD was 63% at day 7 and 73% at day 14. Therefore test conditions are considered acceptable.

% Degradation

% Degradation 1

Parameter:

% degradation (O2 consumption)

Value:

75

St. dev.:

4.73

Sampling time:

14 d

% Degradation 2

Parameter:

% degradation (TOC removal)

Value:

92

St. dev.:

1

Sampling time:

14 d

% Degradation 3

Parameter:

% degradation (test mat. analysis)

Value:

100

St. dev.:

0

Sampling time:

14 d

BOD5 / COD results

Results with reference substance:

Degradation of reference substance, expressed in terms of BOD was 63% at day 7 and 73% at day 14. Therefore test conditions are considered acceptable.

Any other information on results incl. tables

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

Degradation of reference substance, expressed in terms of BOD was 63% at day 7 and 73% at day 14. Therefore test conditions are considered acceptable.

Interpretation of results:

readily biodegradable

Conclusions:

Biodegradation at 14 d expressed in terms of BOD with respecto to ThOD is >60%. Thereby according to criteria for OECD method 301C, the substance is considered to be readily biodegradable.

Executive summary:

Report on test performed in 1994 under Chemicals Programme sponsored by Japanese Ministry of International Trade and Industry (MITI) according to OECD Guideline 301C and under GLP indicates that analogue sodium ditartrate is readily biodegradable under specified test conditions after 14d. Biodegradability was estimated according to three parameters: BOD reduction, TOC reduction and test substance reduction as estimated by HPLC. The minimum average % biodegradation (mean of three replicates) obtained was of 75% in terms of BOD and of 100% as determined by substance disappearance estimated by HPLC analysis. Thereby, as predicted from its molecular structure disodium tartrate is considered to be readily biodegradable, as > 60% biodegradation is obtained in the MITI test. This analogue is considered to be a suitable predictor of the biodegradability of Potassium Sodium Tartrate, as the organic group of the submission substance is identical, being the only difference the exchange of one sodium atom for a potassium atom, which is irrelevant in terms of the degradable organic portion of the molecule.