Sodium cumenesulphonate

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Specific details on test material used for the study:

CAS Number: 28348-53-0
Identity: Cumene sulfonic acid, sodium salt
Purity: 45%
Remarks: Substances tested are aqueous solutions; % purity equates to chemical content

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): aeration pond of local wastewater treatment plant
- Laboratory culture:
- Method of cultivation:
- Storage conditions: aerated in carboy in the laboratory
- Storage length: approximately 30 days
- Preparation of inoculum for exposure: the sludge was maintained by the daily addition of synthetic sewage food; pH adjusted with dilute HCl to maintain a range of 6.5 - 8.0; dissolved oxygen maintained at least 2.0 mg/L;
- Pretreatment: preacclimation phase was 9 days in duration
- Concentration of sludge: 500 mL from each of two SCAS units combined
- Initial cell/biomass concentration:
- Water filtered: yes
- Type and size of filter used, if any: ABC reagent water (equivalent to ASTM Type I) was used in the test. The water was purififed by a LABCONCO Water Pro Water Purifier PS.

Duration of test (contact time):

>= 28 d

Initial conc.:

>= 10 - <= 20 mg/L

Based on:

DOC

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- Composition of medium: inorganic nutrient medium (see Table 1)
- Additional substrate: no
- Solubilising agent (type and concentration if used): no data
- Test temperature: 22+/- 3 degrees C
- pH: 7
- pH adjusted: no
- Aeration of dilution water: stir bar
- Suspended solids concentration: used supernatant
- Continuous darkness: yes
- Other: acclimation in SCAS units


TEST SYSTEM
- Culturing apparatus: sodium acetate carboy
- Number of culture flasks/concentration: one
- Method used to create aerobic conditions: aerate with CO2 free air
- Test performed in closed vessels
- KOH traps used
- Other: Shimadzu Model 5050 Total Carbon Analyzer used for CO2 analysis (combustion at 680 degrees C and nondispersive infrared detection


SAMPLING
- Sampling frequency: days 2,4,6,8,10,15,20,25 and 28
- Sampling method: CO2 produced in the test systems was trapped in KOH solutions in the gas-washing bottles
- Sterility check if applicable: no data
- Sample storage before analysis: 7 mL aliquats in glass scintillation vials without headspace; teflon-lined cap; room temperature
- Other: standard plate count to enumerate the microbial populations was also performed


CONTROL AND BLANK SYSTEM
- Inoculum blank: yes
- Abiotic sterile control: yes
- Toxicity control: no data
- Other: reference material - sodium acetate

Reference substance:

acetic acid, sodium salt

Preliminary study:

DOC analysis of the supernatant samples from the SCAS units indicated the inoculum had adapted to the test material within the 15-day period by the 81% degradation exhibited

Test performance:

49 mg CO2 evolved in the control system which is in the acceptable range per the guideline. Plate count analysis indicated the inoculum was viable and active.

Key result

Parameter:

% degradation (CO2 evolution)

Value:

>= 103 - <= 109

Sampling time:

28 d

Details on results:

The substance is biodegradable (> 60% THCO2 within 28 days), more than 60% after 6 days.

Results with reference substance:

The day 0 total carbon analysis value was 15.03 mg C/L. The 60% threshold value was attainged in the reference system (sodium acetate) by Day 6 verifying the microbial inoculum was viable and active. 93% of the theoretical CO2 was attained at the end of the 28 days

results in %THCO2       

 

day	2	4	6	8	10	15	20	25	28
10 mg Carbon/L	4.96	34.66	65.31	89.38	96.24	102.44	106.36	106.36	109.43
20 mg C/L	2.75	13.18	82.03	86.75	88.54	96.69	100.46	100.46	103.21
Reference	17.85	29.00	80.81	83.15	85.30	92.62	93.21	93.21	93.21

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The substance sodium cumenesulphonate is biodegradable (> 60% THCO2 within 28 days), more than 60% after 6 days.

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

other: published data

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Specific details on test material used for the study:

Test Substance
CAS Number: 1300-72-7
Identity: Xylene sulfonic acid, sodium salt
Purity: 40%
Remarks: Substance tested are aqueous solutions; % purity equates to chemical content

Oxygen conditions:

aerobic

Inoculum or test system:

sewage, domestic (adaptation not specified)

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): activated sludge from aeration pool of local wastewater treatment plant
- Storage conditions: aerated in carboy until use
- Storage length: less than 30 days
- Preparation of inoculum for exposure: the sludge was maintained by the daily addition of synthetic sewage food; pH adjusted with dilute HCl to maintain a range of 6.5 - 8.0; dissolved oxygen maintained at least 2.0 mg/L;
- Pretreatment: preacclimation phase was 9 days in duration
- Concentration of sludge: 500 mL from each of two SCAS units combined
- Initial cell/biomass concentration:
- Water filtered: yes
- Type and size of filter used, if any: LABCONCO Water Pro Water Purifier PS

Duration of test (contact time):

>= 28 d

Initial conc.:

>= 10 - <= 20 mg/L

Based on:

DOC

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- Composition of medium: inorganic nutrient medium (see Table 1)
- Additional substrate: no
- Solubilising agent (type and concentration if used): no data
- Test temperature: 22+/- 3 degrees C
- pH: 7
- pH adjusted: no
- CEC (meq/100 g): no data
- Aeration of dilution water: stir bar
- Suspended solids concentration: used supernatant
- Continuous darkness: yes
- Other: acclimation in SCAS units; conducted acclimated and unacclimated tests in duplicate

Reference substance:

acetic acid, sodium salt

Preliminary study:

DOC analysis of the supernatant samples from the SCAS units indicated the inoculum had adapted to the test material within the 15-day period by the 82% degradation exhibited

Test performance:

49 mg CO2 evolved in the control system which is in the acceptable range per the guideline. Plate count analysis indicated the inoculum was viable and active.

Parameter:

% degradation (CO2 evolution)

Value:

>= 83 - <= 85

Sampling time:

28 d

Details on results:

The 60% threshold value was attained by the test substance by day 6 in both the 10 and 20 mg C/L test systems where the test substance SCAS acclimated inoculum was used. The carboys containing the nontest substance acclimated inoculum exceeded the 60% threshold by day 15 for both the 10 and 20 mg C/L units

Results with reference substance:

The 60% threshold value was attained by day 6. 93.2% of the theoretical CO2 evolution was attained at the end of the 28-day study.

Results

day	2	4	6	8	10	15	20	25	28
10 mg Carbon/L	3.32	3.32	21.04	51.22	59.82	74.23	79.82	80.29	83.88
20 mg C/L	2.53	2.53	26.22	46.14	52.94	63.51	66.83	67.39	69.30
Reference	17.85	29.00	80.81	83.15	85.30	92.62	93.21	93.21	93.21

Reported as %THCO2

The substance is biodegradable, more than 60% after 15 days

Remarks: 74% degraded in 15 days; 84% in 28 days at 10 mg C/L

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

Data of following studies are demonstrating rapid biodegradation of the substance under aerobic conditions. The substance is biodegradable, more than 60% after 15 days.
This test was carried out according to the guidelines of OECD Guide-line 301 B "Ready Biodegradability: Modified Sturm Test (CO2 evolution)"

Description of key information

The substance sodium cumenesulphonate is biodegradable (> 60% THCO2 within 28 days), more than 60% after 6 days.Biodegradation constitutes the primary elimination mechanism from the environment. Studies with sodium cumenesulphonate demonstrate rapid and complete biodegradation under aerobic conditions and sodium cumenesulphonate is considered to be readily biodegradable according to OECD criteria.

There is no known anaerobic biodegradation data on sodium cumenesulphonate. Due to the presence of the sulphonated aromatic group, sodium cumenesulphonate is not expected to biodegrade to a significant extent under anaerobic conditions. However, considering their ready aerobic biodegradability and their low potential for adsorption to sediment solids (log Kow), the presence of sodium cumenesulphonate in anaerobic environments is expected to be negligible.

 

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable