Asphalt, sulfonated, sodium salt

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:

1991-08-29 to 1991-10-24

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

GLP and EC Guideline EU Method C.4-E (Determination of the "Ready" Biodegradability - Closed Bottle Test)

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1993

Report date:

1993

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EU Method C.4-E (Determination of the "Ready" Biodegradability - Closed Bottle Test)

Principles of method if other than guideline:

N/A

GLP compliance:

yes

Remarks:

statement; no certificate

Test material

Test material information

Constituent 1

Reference substance name:

Soltex

IUPAC Name:

Soltex

Constituent 2

Reference substance name:

Soltex contains 85% w/w Asphalt, sulfonated, sodium salt (CAS # 68201-32-1) (EC # 269-212-0)

IUPAC Name:

Soltex contains 85% w/w Asphalt, sulfonated, sodium salt (CAS # 68201-32-1) (EC # 269-212-0)

Details on test material:

- Name of test material (as cited in study report): 3.5% bentonite slurry with 1% Soltex
- Molecular formula (if other than submission substance): N/A
- Molecular weight (if other than submission substance): N/A
- Smiles notation (if other than submission substance): N/A
- InChl (if other than submission substance): N/A
- Structural formula attached as image file (if other than submission substance): N/A
- Substance type: Active
- Physical state: Dark brown liquid
- Analytical purity: N/A
- Impurities (identity and concentrations): N/A
- Composition of test material, percentage of components: Soltex has 85% w/w asphalt, sulfonated, sodium salt
- Isomers composition: N/A
- Purity test date: N/A
- Lot/batch No.: N/A
- Expiration date of the lot/batch: N/A
- Stability under test conditions: N/A
- Storage condition of test material: Room temperature in a closed cabinet
- Other: Test material provided by sponsor

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

natural water

Details on inoculum:

N/A

Duration of test (contact time):

56 d

Initial test substance concentration

Initial conc.:

3 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: Natural seawater
- Additional substrate: Added nutrient stock solution, see below for details
- Solubilising agent (type and concentration if used): N/A
- Test temperature: 20.2-20.9 deg C
- pH: 7.7-8.0
- pH adjusted: no
- CEC (meq/100 g): N/A
- Aeration of dilution water: yes
- Suspended solids concentration: N/A
- Continuous darkness: yes
- Other: N/A


TEST SYSTEM
- Culturing apparatus: N/A
- Number of culture flasks/concentration: 3
- Method used to create aerobic conditions: N/A
- Method used to create anaerobic conditions: N/A
- Measuring equipment: DO meter
- Test performed in closed vessels due to significant volatility of test substance: No, test requires it.
- Test performed in open system: No
- Details of trap for CO2 and volatile organics if used: N/A
- Other: N/A


SAMPLING
- Sampling frequency: initially, 7, 14, 21, 28 days, all treatments, and 42 and 56days reference and test substance
- Sampling method: DO measurement via probe
- Sterility check if applicable: N/A
- Sample storage before analysis: N/A
- Other: N/A


CONTROL AND BLANK SYSTEM
- Inoculum blank: N/A
- Abiotic sterile control: N/A
- Toxicity control: N/A
- Other: N/A


STATISTICAL METHODS: N/A

Reference substance

Reference substance:

acetic acid, sodium salt

Results and discussion

Preliminary study:

N/A

Test performance:

See details above.

% Degradation

Parameter:

% degradation (O2 consumption)

Value:

> 0 - < 3

Sampling time:

28 d

Details on results:

The results showed the expected rapid degradation of acetate (complete within seven days). The measured oxygen consumption of acetate was 0.66 mg O2/mg after seven days and compared well with the theoretical oxygen demand of 0.68 mg O2/mg.

The calculated oxygen consumption of acetate in the presence of the test substance was slightly lower than found with acetate alone, indicating that Soltex had a slightly inhibiting effect on the acetate degradation.

The oxygen consumption due to the acetate in presence of the 3.5% bentonite slurry was similar to that of acetate and Soltex, confirming that the effect recorded above was probably caused by the bentonite slurry.

Soltex was not degraded in the presence of acetate.

BOD5 / COD results

Results with reference substance:

0.63 mg oxygen consumption per mg sodium acetate.

Any other information on results incl. tables

N/A

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

No oxygen consumption was found which could be attributed to the biological degradation of Soltex.

Executive summary:

N/A