Diammonium tartrate

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

29 Jun - 27 Jul 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)

Version / remarks:

adopted July 17, 1992

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: municipal sewage treatment plant, Hildesheim, Germany
- Storage conditions: the activated sludge was washed twice with chlorine free tap water. After the second washing the settled sludge was resuspended in mineral salts medium and was maintained in an aerobic condition by aeration for 2 h. Thereafter the sludge was homogenized with a blender. After sedimentation the supernatant was decanted and maintained in an aerobic condition by aeration with CO2-free air for 6 days.
- Concentration of sludge: 10 mL/L were used to initiate inoculation
- Initial cell/biomass concentration: approx. 10^7 CFU/L in the final test solution
- Water filtered: no

Duration of test (contact time):

28 d

Initial conc.:

117 mg/L

Based on:

test mat.

Initial conc.:

50.3 other: mg O2/L

Based on:

ThOD

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: mineral salts medium according to OECD 301 F
- Test temperature: 20.2 - 20.5 °C
- pH: 7.05 - 7.86
- pH adjusted: no
- Aeration of dilution water: no
- Continuous darkness: yes

TEST SYSTEM
- Culturing apparatus: 500 mL brown glass bottles with OxiTop® measuring heads
- Number of culture flasks/concentration: 2
- Measuring equipment: OxiTop® OC110 controller with software Achat OC, WTW OxiTop® measuring heads, WTW Stirring platform, WTW
- Test performed in open system: no
- Details of trap for CO2 if used: rubber sleeve with soda lime was hung into the opening of the bottles

SAMPLING
- Sampling method and frequency: the oxygen consumption was determined in the vessels by the OxiTop® measuring system at 360 measuring points (every 112 min) during the 28 d incubation period.
- Other: temperature was documented continuously. The pH of the inoculum control, functional control, test item and toxicity control were determined at test start and test end.

CONTROL AND BLANK SYSTEM
- Inoculum control: 2
- Functional control: 1
- Toxicity control: 1

Reference substance:

benzoic acid, sodium salt

Parameter:

% degradation (O2 consumption)

Value:

90

Sampling time:

28 d

Remarks on result:

other: Biodegradation was based on the ThODNO3

Details on results:

- Toxicity control: the degradation of the reference item was not inhibited by the test item since In the toxicity control containing both test and reference item 61% degradation occurred within 14 days and 91% after 28 d.

Results with reference substance:

The adaptation phase changed to degradation phase within 1 day (degradation > 10%). The pass level for ready biodegradation (> 60% degradation) was reached on day 4.The biodegradation came to a maximum of 93% on day 24.

Both test item replicates reached the 10% level (beginning of biodegradation) on day 2. The course of the degradation was biphasic and the mean of test item replicates reached the 60% pass level on day 19.

Table 1: Biological Oxygen Demand of Inoculum Control, Functional Control, Test Item and Toxicity Control

Date	BOD [mg O2/L]
	[d]	Inoculum Control	Functional Control		Test Item				Toxicity Control
					R1		R2
		mean	gross	net	gross	net	gross	net	gross	net
6/30/2016	1	1.9	1.7	-0.2	1.6	-0.3	1.9	0.1	5.5	3.6
7/1/2016	2	4.1	34.9	30.8	22.1	18	22.6	18.5	62.9	58.8
7/2/2016	3	4.9	47.3	42.4	33	28.1	34	29.1	82.1	77.2
7/3/2016	4	5.1	55.8	50.7	42	36.9	42.7	37.6	96.5	91.4
7/4/2016	5	5.8	61.7	55.9	46.4	40.6	46.7	40.9	103.7	97.9
7/5/2016	6	6.3	64.6	58.3	49.2	42.9	50.4	44.1	109.2	102.9
7/6/2016	7	6.3	66.6	60.3	51.5	45.2	52.6	46.3	114.2	107.9
7/7/2016	8	6.7	68.1	61.4	53.1	46.3	54.7	47.9	117.1	110.3
7/8/2016	9	7.1	69.7	62.6	54.7	47.6	56.6	49.6	119.8	112.7
7/9/2016	10	7.6	70.9	63.3	56.3	48.7	58.1	50.5	122.8	115.1
7/10/2016	11	7.8	71.9	64.2	58.6	50.9	59.9	52.2	124.4	116.7
7/11/2016	12	7.9	73.3	65.4	60.7	52.8	61.6	53.6	127.5	119.6
7/12/2016	13	7.8	73.6	65.9	63.6	55.9	63.8	56.1	130.5	122.8
7/13/2016	14	8	74.7	66.7	67.1	59.1	66.2	58.2	133.6	125.6
7/14/2016	15	8.4	75.6	67.2	70.8	62.4	68.5	60.1	137.8	129.5
7/15/2016	16	8.6	75.9	67.3	73.9	65.4	69.7	61.1	142.7	134.1
7/16/2016	17	9.1	76.2	67.1	81.5	72.4	73.3	64.2	149.2	140.1
7/17/2016	18	9.2	76.8	67.6	90.2	81	77.9	68.7	155.3	146.1
7/18/2016	19	9.2	77.5	68.3	100	90.8	82.9	73.7	162.7	153.5
7/19/2016	20	9.3	77.9	68.7	108.8	99.5	89.8	80.5	170.8	161.6
7/20/2016	21	10	78.9	68.9	115	105	97.3	87.3	178.4	168.4
7/21/2016	22	10.4	79.2	68.8	118.8	108.3	104.1	93.6	183.8	173.3
7/22/2016	23	10.5	80	69.4	122.2	111.7	108.8	98.2	187	176.5
7/23/2016	24	10.6	80.3	69.7	125.2	114.6	112.7	102.1	189.5	178.9
7/24/2016	25	10.6	80.3	69.7	127.4	116.8	116.7	106.1	192.3	181.7
7/25/2016	26	10.6	80.4	69.8	129.2	118.6	120.1	109.5	194.5	183.9
7/26/2016	27	11.1	80.5	69.4	131	119.9	123.8	112.6	197.8	186.6
7/27/2016	28	11.2	80.7	69.5	131.9	120.7	127	115.8	200.6	189.4

Table 2: % Biodegradation

Date	[d]	Functional Control	Test Item		Toxicity Control
			R1	R2
6/30/2016	1	0	0	0	2
7/1/2016	2	41	14	14	28
7/2/2016	3	56	21	22	37
7/3/2016	4	67	28	28	44
7/4/2016	5	74	31	31	47
7/5/2016	6	78	32	33	50
7/6/2016	7	80	34	35	52
7/7/2016	8	82	35	36	53
7/8/2016	9	83	36	37	54
7/9/2016	10	84	37	38	56
7/10/2016	11	85	38	39	56
7/11/2016	12	87	40	41	58
7/12/2016	13	88	42	42	59
7/13/2016	14	89	45	44	61
7/14/2016	15	89	47	45	62
7/15/2016	16	90	49	46	65
7/16/2016	17	89	55	49	68
7/17/2016	18	90	61	52	70
7/18/2016	19	91	69	56	74
7/19/2016	20	91	75	61	78
7/20/2016	21	92	79	66	81
7/21/2016	22	91	82	71	84
7/22/2016	23	92	84	74	85
7/23/2016	24	93	87	77	86
7/24/2016	25	93	88	80	88
7/25/2016	26	93	90	83	89
7/26/2016	27	92	91	85	90
7/27/2016	28	92	91	88	91

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable, but failing 10-day window

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

Please refer to the analogue justification provided in IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Parameter:

% degradation (O2 consumption)

Value:

> 71 - < 80

Sampling time:

14 d

Remarks on result:

other: based on BOD

Parameter:

% degradation (TOC removal)

Value:

> 91 - < 93

Sampling time:

14 d

Remarks on result:

other: based on TOC

Parameter:

% degradation (test mat. analysis)

Value:

100

Sampling time:

14 d

Remarks on result:

other: based on HPLC

Results with reference substance:

The oxygen consumption for aniline in the above used test system reached 63% and 73% degradation after 7 days and 14 days, respectively.

Interpretation of results:

readily biodegradable

Reference 3

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

08 July - 22 July 1994

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

1992

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: Circular on Test Methods of New Chemical Substances (Japan), biodegradation test

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: cool and dark
- Stability under test conditions: verified at the beginning and at the end of the test by IR

Oxygen conditions:

aerobic

Inoculum or test system:

mixture of sewage, soil and natural water

Details on inoculum:

- Source of inoculum/activated sludge: in June 1988, sludge was sampled at the following 10 places in Japan: 1. Fukogawa city sewage plant, 2. Fukashiba industry sewage plant, 3. Nakahama city sewage plant, 4. Ochiai city sewage plant, 5. Kitakami river, 6. Shinano river, 7. Yoshino river, 8. Lake Biwa, 9. Hiroshima bay, and 10. Dookai bay.
- Sampling method: return sludge at sewage disposal plants was taken. Surface water and surface soil on the beach which is in contact with atmosphere were taken from rivers, lake and sea.
- Method of cultivation: 5 L of the filtrate of the supernatant of old activated sludge was mixed with 500 mL of the filtrate of the supernatant of new sludge and cultured at pH 7.0 ± 1.0 under sufficient aeration using filtered air. About 30 minutes after ceasing aeration to the sludge mixture, supernatant corresponding to about 1/3 of the whole volume was removed. Then the equal volume of dechlorinated water was added to the remaining portion and aerated again, followed by addition of synthetic sewage at a concentration of 0.1% (w/v). This procedure was repeated once every day. The culturing was carried out at 25 ± 2 °C. During the cultivation, appearance of the supernatant, precipitability, formation of flock, pH, dissolved oxygen concentration in the solution and temperature were checked and necessary adjustments were made. Microflora in the activated sludge was microscopically observed and sludge with no abnormal symptom was used for the test.
- Concentration of sludge: 30 mg/L

Duration of test (contact time):

14 d

Initial conc.:

100 mg/L

Parameter followed for biodegradation estimation:

O2 consumption

Parameter followed for biodegradation estimation:

TOC removal

Parameter followed for biodegradation estimation:

test mat. analysis

Details on study design:

TEST CONDITIONS
- Composition of medium: 3 mL of each four stock solutions, as described in Japanese Industrial Standards K 0102-1986-21, are diluted in 1000 mL of purified water
- pH: 6.4 - 7.0 (before start), 6.6 - 8.7 (at the end of the study)
- pH adjusted: no
- Suspended solids concentration: determined according to Method Japanese Industrial Standards (JIS) K 0102-1986-14.1

TEST SYSTEM
- Culturing apparatus: closed system oxygen consumption measuring apparatus (Coulometer: Ohkura Electric Co., Ltd.); 300 mL vessels).
- Number of culture flasks/concentration: 3 (sludge + test sub.)
- Measuring equipment: Coulometer, Ohkura Electric Co., Ltd.
- Test performed in open system: no
- Details of trap for CO2 and volatile organics if used: soda lime, extra pure, Wako Pure Chemical Industries, Ltd.

CONTROL AND BLANK SYSTEM
- Inoculum blank: 1 (sludge)
- Inoculum control: 1 (sludge + reference substance)
- Abiotic control: 1 (water + test substance)
- Toxicity control: no

Reference substance:

aniline

Parameter:

% degradation (O2 consumption)

Value:

> 71 - < 80

Sampling time:

14 d

Remarks on result:

other: based on BOD

Parameter:

% degradation (TOC removal)

Value:

> 91 - < 93

Sampling time:

14 d

Remarks on result:

other: based on TOC

Parameter:

% degradation (test mat. analysis)

Value:

100

Sampling time:

14 d

Remarks on result:

other: based on HPLC

Results with reference substance:

The oxygen consumption for aniline in the above used test system reached 63% and 73% degradation after 7 days and 14 days, respectively.

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Description of key information

Diammonium tartarate (CAS 3164-29-2) is readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

freshwater

Additional information

One study is available, testing the biodegradability of diammonium tartrate (CAS 3164-29-2). The study was conducted according to the OECD guidance 301 F and GLP standards. Domestic, non-adapted activated sludge was exposed for 28 d to an initial test item concentration of 117 mg test item/L. The biodegradation of the substance was monitored based on oxygen consumption. A toxicity control containing the reference substance benzoic acid, sodium salt and the test item was run in parallel. The course of the degradation was biphasic implying nitrification and the biodegradation was evaluated based on the ThOD_NO3. Both replicates of the test item reached the 10% level (beginning of biodegradation) on day 2 and the mean of test item replicates reached the 60% pass level on day 19. After 28 d incubation a biodegradation of 90% was recorded. According to this study the substance was readily biodegradable, failing the 10-day window. It is known that nitrogen can affect the results of biodegradability studies due to nitrification processes in the sludge. Therefore, in order to gain further information on the biodegradability of tartrate salts, data on biodegradation from the appropriate read across substance disodium tartrate (CAS 868-18-8), as representative of tartrate salts, were used for further evidence. The biodegradation study of disodium tartrate was conducted according to the OECD guidance 301 C and GLP standards. A mixture of sewage sludge, soil and natural water was used as inoculum and was exposed to an initial test item concentration of 100 mg/L. The biodegradation was monitored based on O2 consumption, TOC removal and test material analysis via HPLC. After 14 d incubation following biodegradation was recorded: 71 – 80% based on BOD, 91 – 93% based on TOC removal and 100% based on test material analysis, showing that the substance is readily biodegradable.

On the basis of the available data the substance diammonium tartrate is considered readily biodegradable.