Benzododecinium chloride

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:

weight of evidence

Study period:

1986

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)

Deviations:

not specified

GLP compliance:

not specified

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, domestic (adaptation not specified)

Details on inoculum:

The inoculum used was one drop/L of filtered effluent from sewage works treating predominantly domestic sewage. The test were conducted at 20 +/- 1 deg C and BOD determinations were made after 5, 15 and 28 days.

Duration of test (contact time):

ca. 28 d

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

The inoculum used was one drop/L of filtered effluent from sewage works treating predominantly domestic sewage. The test were conducted at 20 +/- 1 deg C and BOD determinations were made after 5, 15 and 28 days.

Key result

Parameter:

% degradation (O2 consumption)

Remarks:

2 mg/L test substance

Value:

ca. 43

Sampling time:

28 d

Key result

Parameter:

% degradation (O2 consumption)

Remarks:

3.2 mg/L test substance

Value:

ca. 23

Sampling time:

25 d

Key result

Parameter:

% degradation (O2 consumption)

Remarks:

5 mg/L test substance

Value:

ca. 36

Sampling time:

28 d

Details on results:

Toxicity Values: To facilitate a comparison of the test results, toxicity values were (with the exception of the Closed Bottle test) expressed as EC50 values, the concentrations of test substances causing a 50% inhibition in the test. The test substance showed a clear pattern of response for growth Inhibitionwith EC50 values ranging between 3.2 -7.5 mg/L.

Results

Test substance (mg/L)	% Biodegradation on days							Biodegradation category
	3	5	7	14	21	25	28
2	-	-	-	-	-	-	43	II – long delay/partial biodegradation
3.2	0	0	0	0	5	23	-	I – little or no biodegradation
5	-	-	-	-	-	-	36	II – long delay/partial biodegradation

Validity criteria fulfilled:

not specified

Interpretation of results:

inherently biodegradable

Remarks:

(due to toxicity of the test concentrations to the inoculum)

Conclusions:

Under the study conditions, the test substance was determined to be not readily biodegradable (with 23-43% degradation after 28 days).

Executive summary:

A study was conducted to determine the ready biodegradability of the test substance, C12 ADBAC (purity not specified), using closed bottle test, according to the OECD Guideline 301D. The inoculum used was one drop/L of filtered effluent from sewage works treating predominantly domestic sewage. The test was conducted in two different laboratories using 2, 3.2 and 5 mg/L test concentrations at 20 +/- 1 deg C, followed by BOD determinations after 5, 15 and 28 days. The three test concentrations resulted in 43, 23 and 36% degradation after 28 days. The lowest (2 mg/L) and highest concentrations (5 mg/L) revealed long delay with partial degradation, while the mid concentration (3.2), showed little or no biodegradation. The lag phase was attributed to the toxicity of the test substance to the inoculum. Based on the growth inhibition test conducted for test substance, the EC50 value was determined to be 3.2 -7.5 mg/L. Therefore, the test concentration below the EC50 value i.e., 2 mg/L results in the highest degradation potential. No further details about biodegradation were available. Under the study conditions, the test substance was considered to be not readily biodegradable and this is attributed to the toxicity of the test substance to the inoculum instead of inertness (ECETOC, 1986).   

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

1986

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

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

Deviations:

not specified

GLP compliance:

not specified

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, domestic (adaptation not specified)

Details on inoculum:

Inoculum was collected from a local sewage works which treated predominantly domestic effluents. The inoculum at a concentration of 15 mg/L suspended solids (SS) was pre-aerated for eight days at 23 deg C in the mineral solution before addition of the test substance.

Duration of test (contact time):

ca. 21 d

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

Inoculum was collected from a local sewage works which treated predominantly domestic effluents. The inoculum at a concentration of 15 mg/L suspended solids (SS) was pre-aerated for eight days at 23 deg C in the mineral solution before addition of the test substance. Carbon dioxide evolution was measured as a test parameter after 3, 5, 7, 14 and 21 days.

Key result

Parameter:

% degradation (CO2 evolution)

Remarks:

6.8 mg/L test substance

Value:

ca. 100

Sampling time:

21 d

Key result

Parameter:

% degradation (CO2 evolution)

Remarks:

13.5 mg/L test substance

Value:

ca. 92

Sampling time:

21 d

Details on results:

Toxicity Values: To facilitate a comparison of the test results, toxicity values were (with the exception of the Closed Bottle test) expressed as EC50 values, the concentrations of test substances causing a 50% inhibition in the test. The test substance showed a clear pattern of response for growth Inhibitionwith EC50 values ranging between 10 - 24 mg/L.

Results

Test substance (mg/L)	Biodegradation (%)					Biodegradation category
	Day 3	Day 5	Day 7	Day 14	Day 21
6.8	0	75	75	89	100+	IIIII – Rapid and complete biodegradation
13.5	-	7	38	77	92	III – Variable delay – complete biodegradation

Validity criteria fulfilled:

not specified

Interpretation of results:

readily biodegradable

Conclusions:

Under the study conditions, the test substance was determined to be readily biodegradable [with 100% (6.8 mg/L) and 92% (13.5 mg/L) biodegradation after 21 days].

Executive summary:

A study was conducted to determine the ready biodegradability of the test substance, C12 ADBAC (purity not specified), using Sturm test, according to the OECD Guideline 301B. The inoculum used was collected from a local sewage works which treated predominantly domestic effluents. The inoculum at a concentration of 15 mg/L suspended solids (SS) was pre-aerated for eight days at 23 deg C in the mineral solution before addition of the test substance. The test was conducted at two test concentrations: 6.8 and 13.5 mg/L at 23 deg C, followed by CO2 determinations after 3, 5, 7, 14 and 21 days. The two test concentrations resulted in 100 and 92% degradation after 21 days. Based on the growth inhibition test conducted for test substance, the EC50 value was determined to be 10 - 24 mg/L. Therefore, the test concentration below the EC50 value i.e., 6.8 mg/L results in the highest degradation potential. No further details about biodegradation were available. Under the study conditions, the test substance was considered to be readily biodegradable (ECETOC, 1986).  

Reference 3

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

January, 2005

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Not GLP

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

no

Specific details on test material used for the study:

- Name of test material (as cited in study report): active substance (alkyl(C12-C16)dimethylbenzylammonium chloride (ADBAC) in aqueous/ethanol solution).
- Stability under test conditions: ADBAC is hydrolytically and photolytically stable under the conditions of this study and has been shown to be stable in aqueous, alcohol and alcohol/aqueous solutions for extended periods, e.g. at least five years under standard laboratory conditions
- Storage condition of test material: At room temperature

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

>106 CFU/mL; consisting of micro-organisms in mud collected from Station Epuration Wavre 2nd Stage, a household water treating plant

Duration of test (contact time):

28 d

Initial conc.:

5 other: mgC/L

Based on:

test mat.

Remarks:

Testing at low concentrations, was required due to the toxicity of the test substance towards the inoculum at higher concentrations (see section 6.1.7 of IUCLID)

Details on study design:

Test conditions:
- Test temperature: 22 ± 2°C
- pH: 7.3 at start and 7.8 at the end of study
- Aeration of dilution water: Air free from carbon dioxide was passed through the solutions using a flow of 50 to 100 mL/min
- Continuous darkness: Yes
- Other: Total organic carbon content: 62.8%
Test system:
- Culturing apparatus: 3-litre flasks mounted with an aeration tube on a magnetic stirrer
- Details of trap for CO2 and volatile organics if used: the CO2 produced in each flask was precipitated with Ba(OH2). The amount of CO2 produced was determined by titration.

Reference substance:

benzoic acid, sodium salt

Remarks:

20 mgC/L

Key result

Parameter:

% degradation (CO2 evolution)

Value:

95.5

Sampling time:

28 d

Details on results:

- The biodegradability in the test flask was determined to be 95.5% after 28 days (See Table 1 under 'Any other information on results inc. tables).
- The CO2 production in the blank (inoculum control) was 39.2 mg. The pH measured at the start and end of the test period was 7.3 and 7.8, respectively. The temperature throughout the test ranged from 20.8 to 21.4°C.

Results with reference substance:

The biodegradability in the reference flask was determined to be 88.9% after 28 days (See Table 1 under 'Any other information on results inc. tables and the graph under 'Illustration (picture/graph)'.

Table 1. Biodegradability values:

Day	Reference substance		Test substance
	% CO2Produced	% CO2 Total	% CO2Produced	% CO2 Total
0	0.00	0.00	0.0	0.0
1	14.16	14.16	1.2	1.2
3	28.54	42.69	1.0	2.2
6	21.20	63.89	9.5	11.6
8	8.77	72.67	16.0	27.7
10	3.72	76.39	20.2	47.9
13	3.26	79.65	17.4	65.3
15	2.53	82.18	7.5	72.8
17	1.47	83.65	5.1	77.9
20	2.31	85.95	3.9	81.8
22	1.15	87.11	1.6	83.5
24	0.25	87.36	4.4	87.8
28	0.16	87.52	1.8	89.6
29	1.35	88.87	5.8	95.5

For details on results of replicates of test substance and the graphs of test and reference substances, please refer to the attachment under 'Attached background material'.

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

Under the test conditions, the biodegradation of the test substance in water was determined to be 95.5 after 28 days (CO2 evolution). The test substance was considered to be readily biodegradable.

Executive summary:

A study was conducted to determine the biodegradation of the test substance, C12-16 ADBAC, in water according to OECD Guideline 301B (CO2 evolution test). Flasks containing inoculum from a household water-treating plant dosed with the equivalent of 5 mg C/L test or 20 mg C/L reference substances were maintained for 28 d. Testing at low concentrations, was required due to the toxicity of the test substance towards the inoculum at higher concentrations. Biodegradability was calculated from the released CO2 over time in the test and reference flasks compared to the blank control (a flask prepared without test or reference substance). CO2 production in the blank (inoculum control) was 39.2 mg. Biodegradability in the reference flask was determined to be 88.9% after 28 d. Under the test conditions, the biodegradation of the test substance in water was determined to be 95.5% after 28 d (CO2 evolution). The test substance was considered to be readily biodegradable (van Dievoet, 2005).

Reference 4

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

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

Adequacy of study:

weight of evidence

Study period:

January, 2005

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Not GLP

Justification for type of information:

Refer to section 13 of IUCLID for details on the read-across justification. The study with the read across substance is considered sufficient to fulfil the information requirements.

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

>106 CFU/mL; consisting of micro-organisms in mud collected from Station Epuration Wavre 2nd Stage, a household water treating plant

Duration of test (contact time):

28 d

Initial conc.:

5 other: mgC/L

Based on:

test mat.

Remarks:

Testing at low concentrations, was required due to the toxicity of the test substance towards the inoculum at higher concentrations (see section 6.1.7 of IUCLID)

Details on study design:

Test conditions:
- Test temperature: 22 ± 2°C
- pH: 7.3 at start and 7.8 at the end of study
- Aeration of dilution water: Air free from carbon dioxide was passed through the solutions using a flow of 50 to 100 mL/min
- Continuous darkness: Yes
- Other: Total organic carbon content: 62.8%
Test system:
- Culturing apparatus: 3-litre flasks mounted with an aeration tube on a magnetic stirrer
- Details of trap for CO2 and volatile organics if used: the CO2 produced in each flask was precipitated with Ba(OH2). The amount of CO2 produced was determined by titration.

Reference substance:

benzoic acid, sodium salt

Remarks:

20 mgC/L

Key result

Parameter:

% degradation (CO2 evolution)

Value:

95.5

Sampling time:

28 d

Details on results:

- The biodegradability in the test flask was determined to be 95.5% after 28 days (See Table 1 under 'Any other information on results inc. tables).
- The CO2 production in the blank (inoculum control) was 39.2 mg. The pH measured at the start and end of the test period was 7.3 and 7.8, respectively. The temperature throughout the test ranged from 20.8 to 21.4°C.

Results with reference substance:

The biodegradability in the reference flask was determined to be 88.9% after 28 days (See Table 1 under 'Any other information on results inc. tables and the graph under 'Illustration (picture/graph)'.

Table 1. Biodegradability values:

Day	Reference substance		Test substance
	% CO2Produced	% CO2 Total	% CO2Produced	% CO2 Total
0	0.00	0.00	0.0	0.0
1	14.16	14.16	1.2	1.2
3	28.54	42.69	1.0	2.2
6	21.20	63.89	9.5	11.6
8	8.77	72.67	16.0	27.7
10	3.72	76.39	20.2	47.9
13	3.26	79.65	17.4	65.3
15	2.53	82.18	7.5	72.8
17	1.47	83.65	5.1	77.9
20	2.31	85.95	3.9	81.8
22	1.15	87.11	1.6	83.5
24	0.25	87.36	4.4	87.8
28	0.16	87.52	1.8	89.6
29	1.35	88.87	5.8	95.5

For details on results of replicates of test substance and the graphs of test and reference substances, please refer to the attachment under 'Attached background material'.

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

Based on the results of the read across study, the test substance is considered to be readily biodegradable with 95.5% degradation after 28 days (CO2 evolution).

Executive summary:

A study was conducted to determine the biodegradation of the read across substance, C12-16 ADBAC, in water according to OECD Guideline 301B (CO2 evolution test). Flasks containing inoculum from a household water-treating plant dosed with the equivalent of 5 mg C/L test or 20 mg C/L reference substances were maintained for 28 d. Testing at low concentrations, was required due to the toxicity of the read across substance towards the inoculum at higher concentrations. Biodegradability was calculated from the released CO2 over time in the test and reference flasks compared to the blank control (a flask prepared without test or reference substance). CO2 production in the blank (inoculum control) was 39.2 mg. Biodegradability in the reference flask was determined to be 88.9% after 28 d. Under the test conditions, the biodegradation of the read across substance in water was determined to be 95.5% after 28 d (CO2 evolution). The read across substance was considered to be readily biodegradable (van Dievoet, 2005). Based on the results of read across substance study, similar degradation potential can be expected for the test substance.

Description of key information

Based on the available weight of evidence information from OECD 30B and OECD 301D studies with the test and/or the read across substances showing degradation percentages ranging from 23 to 100% for the test substance and 88.9% for the read across substance at a range of concentrations, suggests that the test substance, C12 ADBAC can be overall considered to be readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

freshwater

Additional information

Study 1:A study was conducted to determine the ready biodegradability of the test substance, C12 ADBAC (purity not specified), using closed bottle test, according to the OECD Guideline 301D. The inoculum used was one drop/L of filtered effluent from sewage works treating predominantly domestic sewage. The test was conducted in two different laboratories using 2, 3.2 and 5 mg/L test concentrations at 20 +/- 1 deg C, followed by BOD determinations after 5, 15 and 28 days. The three test concentrations resulted in 43, 23 and 36% degradation after 28 days. The lowest (2 mg/L) and highest concentrations (5 mg/L) revealed long delay with partial degradation, while the mid concentration (3.2), showed little or no biodegradation. The lag phase was attributed to the toxicity of the test substance to the inoculum. Based on the growth inhibition test conducted for test substance, the EC50 value was determined to be 3.2 -7.5 mg/L. Therefore, the test concentration below the EC50 value i.e., 2 mg/L results in the highest degradation potential. No further details about biodegradation were available. Under the study conditions, the test substance was considered to be not readily biodegradable and this is attributed to the toxicity of the test substance to the inoculum instead of inertness (ECETOC, 1986).    

Study 2:A study was conducted to determine the ready biodegradability of the test substance, C12 ADBAC (purity not specified), using Sturm test, according to the OECD Guideline 301B. The inoculum used was collected from a local sewage works which treated predominantly domestic effluents. The inoculum at a concentration of 15 mg/L suspended solids (SS) was pre-aerated for eight days at 23 deg C in the mineral solution before addition of the test substance. The test was conducted at two test concentrations: 6.8 and 13.5 mg/L at 23 deg C, followed by CO2 determinations after 3, 5, 7, 14 and 21 days. The two test concentrations resulted in 100 and 92% degradation after 21 days. Based on the growth inhibition test conducted for test substance, the EC50 value was determined to be 10 - 24 mg/L. Therefore, the test concentration below the EC50 value i.e., 6.8 mg/L results in the highest degradation potential. No further details about biodegradation were available. Under the study conditions, the test substance was considered to be readily biodegradable (ECETOC, 1986).   

Study 3: A study was conducted to determine the biodegradation of the read across substance, C12-16 ADBAC (purity not specified), in water according to OECD Guideline 301B (CO2 evolution test). Flasks containing inoculum from a household water-treating plant dosed with the equivalent of 5 mg C/L test or 20 mg C/L reference substances were maintained for 28 d. Testing at low concentrations, was required due to the toxicity of the read across substance towards the inoculum at higher concentrations. Biodegradability was calculated from the released CO2 over time in the test and reference flasks compared to the blank control (a flask prepared without test or reference substance). CO2 production in the blank (inoculum control) was 39.2 mg. Biodegradability in the reference flask was determined to be 88.9% after 28 d. Under the test conditions, the biodegradation of the read across substance in water was determined to be 95.5% after 28 d (CO2 evolution). The read across substance was considered to be readily biodegradable (van Dievoet, 2005). Based on the results of read across substance study, similar degradation potential can be expected for the test substance.     

The available information on the test and read across substances indicates that the slow or lag in the degradation potential of the substances at higher concentrations is not due to inertness of the substance but due to toxicity to the inoculum. It is generally recommended that the concentration of the substance in the biodegradation test should not exceed 1/10th of the EC50 determined in the toxicity tests. However, this was not the case in the available biodegradation tests with the test substance, as the EC50 value for toxicity to micro-organisms ranges from 3.2-40 mg/L (ECETOC, 1986). In light of these facts and based on the available weight of evidence information from studies with the test and/or the read across substances, suggests that the test substance, C12 ADBAC can be overall considered to be readily biodegradable. ​