Sulfuric acid, mono-C12-14(even numbered)-alkyl esters, ammonium salts

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:

From April 5, 1994 to May 10, 1994

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

Deviations:

no

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes

Remarks:

According to EPA GLP Standards (40 CFR, Part 792)

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
Not applicable

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: Activated sludge was collected from Sycamore Sewage Treatment Plant, Cincinnati, Ohio. This STP receives primarily domestic wastewater
- Storage conditions: Sludge was aerated to prevent settling of solids until ready to use
- Storage length: The inoculum was used on the same day of preparation
- Preparation of inoculum for exposure: The sludge was homogenized (in a blender for 2 minutes at medium speed) and allowed to settle in beaker for approx. 30 minutes and supernatant was carefully decanted. Sufficient volumes of the mixed liquor was collected and treated at one time to provide enough inoculum for all test bottles. Microbial plate counts were also performed on the inoculum. For microbial plate counts, serial dilutions using the nutrient broth (5 g of pancreatic digest of gelatin and 3 g of beef extract in 1 L of bottle) were performed on the inoculum and then plated onto trypticase soy agar plates (agar contained 15 g of pancreatic digest of casein, 5 g of papaic digest of soybean meal, 5 g of sodium chloride and 15 grams of agar in 1 L of water). The plates were incubated at room temperature for 48 h.
- Concentration of sludge: 1% v/v (10 mL/L).
- Initial cell/biomass concentration: 2.3 x 10(5) CFU/mL (average plate count conducted in duplicates)
- Water filtered: Not applicable

Duration of test (contact time):

35 d

Initial conc.:

20 mg/L

Based on:

act. ingr.

Initial conc.:

11 mg/L

Based on:

other: TOC (measured)

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- Composition of medium: The test medium was modified biochemical oxygen demand (BOD) water similar to OECD 301 B media except the addition of 1 mL of 4% (w/v) solution of (NH4)2(SO4)
- Additional substrate: No
- Solubilising agent: None used
- Test temperature: Room temperature
- pH: No data
- pH adjusted: Not reported
- Aeration of dilution water: Test medium (BOD water) was added to each test bottle and connected to the CO2-free apparatus. The test bottles were placed on a rotary shaker at 145±10 rpms at room temperature and aerated overnight.
- Suspended solids concentration: Not reported
- Continuous darkness: Not reported

TEST SYSTEM
- Culturing apparatus: Clear handled Jugs (1 gallon) with stopper containing 2 L final combined volume of test medium, test substance, and inoculum as follows:
1950 mL test medium
40 mL stock solution of test substance
10 mL inoculum
2000 mL Total
- Number of culture flasks/concentration: Two each for test, inoculum blank and procedure control.
- Method used to create aerobic conditions: By continuous aeration with CO2-free air (flow was controlled using flow meters).
- Measuring equipment: Carbon dioxide measuring apparatus consisted of trapping train of three french square jars filled with 100 mL of 0.024 N Ba(OH)2 and were connected in series to the exit air line of each test bottle.
- Test performed in closed vessels: No
- Details of trap for CO2 and volatile organics if used: Three french square jars which were filled with 100 mL of 0.024 N Ba(OH)2 and were connected in series to the exit air line of each test bottle. Periodically the traps nearest to the test bottles were removed for titration and the remaining two traps were moved one place closer to the respective test bottles and a new trap was added to the end of the series. With every change of traps, an extra bottle containing 100 mL of Ba(OH)2 solution was included. This was titrated as the "initial" to determine the amount of CO2 produced in the control (blank). The entire content of each of the Ba(OH)2 traps and "initial" solution were titrated with 0.05 N HCl to end point equivalence.
- Other: The CO2 produced in each bottle was reacted with 0.024N Ba(OH)2 in the traps and precipitated as BaCO3. The amount ofCO2 produced was determined by titrating the remaining Ba(OH)2 in the traps with 0.05N standard HCI. After 35 d the study was terminated by acidifying the flasks with 1 mL conc. HCl and final titration was performed after overnight aeration.

SAMPLING
- Sampling frequency: On Day 0, 3, 5, 9, 15, 17, 23, 29, 35 and 36
- Sampling method: The first base trap in the trapping train was removed, and titrated. The remaining 2 traps were moved forward, and a new trap added to the end of series
- Sample storage before analysis: Not specified

CONTROL AND BLANK SYSTEM
- Inoculum blank: Yes
- Abiotic sterile control: No
- Toxicity control: No
- Reference control: Yes

STATISTICAL METHODS: Not reported

Reference substance:

other: glucose (20 mg/L)

Preliminary study:

Not applicable

Test performance:

No data

Parameter:

% degradation (CO2 evolution)

Value:

21.7

Sampling time:

3 d

Remarks on result:

other: Mean value of 2 replicates, indicating start of 10 d window criterion

Parameter:

% degradation (CO2 evolution)

Value:

60.7

Sampling time:

10 d

Remarks on result:

other: Mean value of 2 replicates, met the 10 day window. (Straight line interpolation between measurements on days 9 and 15.)

Parameter:

% degradation (CO2 evolution)

Value:

70.4

Sampling time:

15 d

Remarks on result:

other: Mean value of 2 replicates

Parameter:

% degradation (CO2 evolution)

Value:

79.1

Sampling time:

29 d

Remarks on result:

other: Mean value of 2 replicates, indicating final percentage of degradation

Details on results:

- Final SOC (in mg/L) of test substance was as found to be <0.2 and 0.3 for replicate 1 and 2 respectively.
- For details on biodegradation results, please refer to 'Table 1' in the ‘Any other information on results incl. tables’.
-Final SOC (in mg/L) was found to be <0.2 in both blanks.

Results with reference substance:

- The Reference material met the validity criteria for the test, greater than 60% biodegradation within 14 d, and within the 10 d window. Pass level of >60% reached at Day 9 in both replicates. (Mean values of all both replicates on Day 3 = 37.9%, Day 9 = 69.4% and Day 29 = 89.4% TCO2)
For details on individual replicate results, please refer to 'Table 2' in the ‘Any other information on results incl. tables’
- Final mg Soluble Organic Carbon (SOC)/L were found to be 0.4 and < 0.2 mg/L in replicate 1 and 2 respectively.

Table 1: Ready Biodegradation Test of C14 alkyl sulfate- sodium (study #35564)

	% of TCO2
Days	Replicate 1	Replicate 2
0	0	0
3	21.45	22.04
5	38.32	36.75
9	58.74	58.73
15	69.37	71.6
17	70.5	73.63
23	78.48	76.65
29	79.87	78.28
35	78.34	77.63
36	78.36	79.99

Table 2: Ready Biodegradation Test of glucose (reference substance)

	% of TCO2
Days	Replicate 1	Replicate 2
0	0	0
3	39.76	35.95
5	55.89	60.14
9	63.71	75.08
15	75.59	90.2
17	78.67	91.85
23	80.11	96.08
29	81.34	97.47
35	79.87	99.12
36	80.59	97.16

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

Sodium tetradecyl sulfate (C14-alkyl sulfate) is readily biodegradable.

Executive summary:

A ready biodegradation test, following OECD 301B guideline, was conducted on sodium tetradecyl sulfate (C14-alkyl sulfate; C14AS). The test concentration was 20 mg active/L, and the inoculum was 1% v/v. The test treatments, inoculum blank and the reference were measured in duplicate.  The deviation between replicate treatments was < 20% (validity criteria of the guideline).

Greater than 10% biodegradation of the test material was reached at Day 3 and > 60% biodegradation was reached at Day 10 in all replicates. At Day 3, the average percent biodegradation was 21.8, and at Day 10, the average percent biodegradation was 60.7.  The final level of biodegradation on Day 29 was 79.1%. Based on these results, C14AS is readily biodegradable. The reference material, glucose reached > 10% biodegradation at Day 3 and > 60% at Day 9 in all replicates. Hence, it met the validity criteria established in the guideline for a reference material. This ready biodegradation test is classified as acceptable, and satisfies the guideline requirements for the OECD 301B.

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)

Deviations:

no

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

other: effluent of domestic sewage treatment plant

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): Sewage treatment plant Hochdahl, municipal treatment plant

Duration of test (contact time):

28 d

Initial conc.:

2 mg/L

Based on:

act. ingr.

Initial conc.:

5 mg/L

Based on:

act. ingr.

Parameter followed for biodegradation estimation:

O2 consumption

Reference substance:

benzoic acid, sodium salt

Parameter:

% degradation (O2 consumption)

Value:

97

Sampling time:

28 d

Remarks on result:

other: 2 mg/L

Parameter:

% degradation (O2 consumption)

Value:

94

Sampling time:

28 d

Remarks on result:

other: 5 mg/L

Results with reference substance:

84% degradation of sodium benzoate after 28 days.

Interpretation of results:

readily biodegradable

Reference 3

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

12 Apr - 13 May 2005

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): Municipal wastewater treatment plant Breisgauer Bucht
- Preparation of inoculum for exposure: washed twice by settling the sludge, decanting the supernatant and resuspending the sludge in aerated tap water
- Concentration of sludge: 30 mg dry solids/L

Duration of test (contact time):

28 d

Initial conc.:

20 mg/L

Based on:

DOC

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- Composition of medium: according to guideline
- Test temperature: 21.0-21.5 °C
- Suspended solids concentration: 30 mg/L dry solids
- Other: constant stirring using magnetic stirrers

TEST SYSTEM
- Culturing apparatus: 2L gas wash bottles
- Number of culture flasks/concentration: 2
- Method used to create aerobic conditions: aerated with CO2-free air at a rate of 50-100 mL/min overnight
- Measuring equipment: IC determination
- Details of trap for CO2 and volatile organics if used: 0.2M NaOH

SAMPLING
- Sampling frequency: Day 0, 4, 7, 11, 14, 21 and 28
- Sampling method: Absorber flask exchanged


CONTROL AND BLANK SYSTEM
- Inoculum blank: 2
- Toxicity control: 1
- Reference control: 1

Reference substance:

benzoic acid, sodium salt

Parameter:

% degradation (CO2 evolution)

Value:

95

Sampling time:

28 d

Parameter:

% degradation (CO2 evolution)

Value:

81.5

Sampling time:

10 d

Details on results:

The 10-day window was fulfilled.
The degradation in the toxicity control was 91.2% within 14 days and 95.8% within 28 days.

Results with reference substance:

Sodium benzoate reached the pass levels for ready biodegradability within 4 days.

Interpretation of results:

readily biodegradable

Reference 4

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

19 Jul -17 Aug 2005

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

Qualifier:

according to guideline

Guideline:

EU Method C.4-C (Determination of the "Ready" Biodegradability - Carbon Dioxide Evolution Test)

Qualifier:

according to guideline

Guideline:

EPA OPPTS 835.3110 (Ready Biodegradability)

GLP compliance:

yes (incl. QA statement)

Remarks:

2003-02-13, The Department of Health of the Government of the United Kingdom

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: A mixed population of activated sludge micro-organisms was obtained on 18 Jul 2005 from the aeration stage of Seven Trent Water sewage treatment plant at Loughborough Leicestershire, UK, which treats predominantly domestic sewage.
- Preparation of inoculum for exposure: washed three times by settlement and resuspension in culture medium, continuous aeration at 21 °C
- Concentration of sludge: 1.8 g/L

Duration of test (contact time):

29 d

Initial conc.:

10 mg/L

Based on:

DOC

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- Test vessels: 5 L glass culture vessels each containing 3 L of solution
- Composition of medium: according to OECD Guideline
- Suspended solids concentration: 30 mg/L
- Temperature: 21 °C
- Method used to create aerobic conditions: Test vessels were sealed and CO2-free air bubbled through the solution at a rate of approx. 40 mL/min, stirred with magnetic stirrer
- CO2 produced by degradation was collected in two 500 mL Dreschel bottles containing 350 mL of 0.05M NaOH
- pH: 7.4-7.5
- pH adjusted: yes
- Continuous darkness: yes

TEST SYSTEM
- Number of culture flasks/concentration: 2
- Measuring equipment: WTW pH/Oxi 340I pH and dissolved oxygen meter

SAMPLING
- Sampling frequency: Day, 0, 1, 2, 3, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 27, 28, 29
- Sample storage before analysis: at -20 °C on day 12 and 18, other samples measured immediately

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

Reference substance:

benzoic acid, sodium salt

Parameter:

% degradation (CO2 evolution)

Value:

100

Sampling time:

28 d

Details on results:

10-day window fulfilled. The test substance is readily biodegradable.
The toxicity control achieved 103% degradation after 28 days.

Results with reference substance:

30 mg/L sodium benzoate were degraded to 92% after 28 days;

Interpretation of results:

readily biodegradable

Reference 5

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

15 Dec 1995 -12 Jan 1996

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)

GLP compliance:

yes (incl. QA statement)

Remarks:

1996, 27th February, The Department of Health of the Government of the United Kingdom

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: Sewage treatment plant Hochdahl (1mL/L culture solution)

Duration of test (contact time):

28 d

Initial conc.:

2 mg/L

Based on:

act. ingr.

Initial conc.:

5 mg/L

Based on:

act. ingr.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Test temperature: 20 ± 1 °C
- Continuous darkness: yes

SAMPLING
- Sampling frequency: Day 0, day 7, day 21 and day 28

Reference substance:

benzoic acid, sodium salt

Parameter:

% degradation (O2 consumption)

Value:

90 - 100

Sampling time:

28 d

Reference 6

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

26 Jan - 23 Feb 1995

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method C.4-A (Determination of the "Ready" Biodegradability - Dissolved Organic Carbon (DOC) Die-Away Test)

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): sewage treatment plant Marl-Ost, obtained on 26 Jan 1995
- Concentration of sludge: 23.9 mg suspended solids/L, 3.98 g dry substance/L

Duration of test (contact time):

28 d

Initial conc.:

13.58 mg/L

Based on:

other: DOC after 3 h

Parameter followed for biodegradation estimation:

DOC removal

Details on study design:

TEST CONDITIONS
- Composition of medium: The test substance was added to a medium and afterwards the inoculum and a mineral medium was added. The solution was stirred and then poured into the Erlenmeyer flasks and stoppered.
- Test temperature: 21.9 - 22.2 °C
- Continuous darkness: yes
- Other: The flasks were put on a shaking machine during the whole test.

TEST SYSTEM
- Culturing apparatus: 2000 mL Erlenmeyer flasks with aluminum caps
- Number of culture flasks/concentration: 2

CONTROL AND BLANK SYSTEM
- Inoculum blank: yes

Reference substance:

benzoic acid, sodium salt

Parameter:

% degradation (DOC removal)

Value:

95

Sampling time:

28 d

Details on results:

The test substance biodegraded by > 60% within the 10-day time window. Thus, it can be regarded as readily biodegradable.

Results with reference substance:

The reference substance was degraded by > 60% within the 10-day time window. Thus, the inoculum and test system are considered reliable.

Table 1: Biodegradation of test substance and reference substance

Time after test start	biodegradation [%]
	Test substance (mean of 2)	Reference substance (mean of 2)
0 h	0	0
3 h	0	0
7 d	87	100
14 d	95	98
21 d	96	99
27 d	98	99
28 d	95	100

Interpretation of results:

readily biodegradable

Reference 7

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:

Refer to the Category Approach Justification document provided in IUCLID6 Section 13.

Reason / purpose for cross-reference:

read-across source

Parameter:

% degradation (CO2 evolution)

Value:

79.1

Sampling time:

29 d

Remarks on result:

other: Mean value of 2 replicates, indicating final percentage of degradation

Remarks:

Source, key, 1191-50-0, 1995

Description of key information

Readily biodegradable according to OECD criteria: 79.1 % after 28 days based on CO2 evolution (OECD 301 B).

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Additional information

Since no reliable biodegradability tests are available for C12-14AS NH4 (CAS 90583-11-2), in accordance to Regulation (EC) No. 1907/2006 Annex XI, 1.5, a read-across to another structurally related substances was conducted. Read-across data on the following substances was used: C14AS Na (1191-50-0), C12AS Na (CAS 151-21-3), a similar C12-14 mixture: C12-14AS TEA (CAS 90583-18-9), C12-14AS Na (CAS 85586-07-8) and C12-16AS Na (73296-89-6).

One GLP study showing ready biodegradation of C14AS Na (CAS 1191-50-0) is available (Hansmann, 1995). This key study was performed according to OECD 301 B guideline using activated, domestic, non-adapted sludge as inoculum and the initial concentration of the test substance 11 mg/L as TOC. Biodegradation measured as CO2 evolution was greater than 60% after 10 days. The final level of biodegradation after 28 days was 79.1%. Based on these results, C14AS Na is readily biodegradable, passing 10-day window.

For the C12AS Na homologue (CAS 151-21-3), a GLP-guideline study according to OECD guideline 301 B is available (Brunswik-Titze, 2005). In this study, activated, non-adapted domestic sludge was used as inoculum and the initial concentration of the test substance was 20 mg/L as DOC. Based on the CO2 evolution measurements, the biodegradation reached 95% after 28 days and the 10-day window was passed. The substance therefore can be considered as readily biodegradable.

Another, supporting study is available for CAS 151-21-3 (Börner, 1996). This GLP test was performed according to OECD 301 D guideline using effluent of domestic sewage treatment plant as inoculum. Two concentrations of the substance were tested: 2 mg/L and 5 mg/L. By measuring O2 consumption, the substance was evaluated to be readily biodegradable. On day 28 biodegradation reached 97% and 94% for the concentrations of 2 mg/L and 5 mg/L respectively, passing the 14-day window in both cases.

One reliable ready biodegradability tests are available for C12-14AS TEA (CAS 90583-18-9). The EU C.4-A method test was performed according to GLP guideline (Diefenbach, 1995) using activated, domestic, non-adapted sludge as inoculum. The initial concentration of the test substance was 13.58 mgL as DOC. The biodegradation reached 87% after 7 days and 95% after 28 days based on DOC removal.

One reliable biodegradability studies are available for C12-14AS Na (CAS 85586-07-8). A key GLP study was performed according to OECD guideline 301 D (Werner, 1996). Activated, non adapted domestic sludge was used as inoculum. The biodegradation after 28 days reached >90%

The biodegradability of C12-16AS Na CAS (73296-89-6) was investigated in a GLP guideline study according to OECD 301 B (Clarke, 2005). Activated, domestic, non-adapted sludge as was used as inoculum and the initial concentration of the test substance was 10 mg/L as DOC. After 28 days of exposure the test substance was completely biodegraded in 100% passing the 10-day window.

Due to structural and property similarities with the tested category member these results also apply to C12-14AS NH4 (CAS 90583-11-2) which is considered to be readily biodegradable according to OECD criteria.