7-aminonaphthalene-1,3,5-trisulphonic acid

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: inherent biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted following OECD guideline, but report does not mention whether GLP was followed and sufficient data is available for interpretation of results.

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:

2001

Report date:

2001

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 302 B (Inherent biodegradability: Zahn-Wellens/EMPA Test)

Deviations:

no

Principles of method if other than guideline:

OECD guideline 302 B followed.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

7-aminonaphthalene-1,3,5-trisulphonic acid

EC Number:

248-394-5

EC Name:

7-aminonaphthalene-1,3,5-trisulphonic acid

Cas Number:

27310-25-4

Molecular formula:

C10H9NO9S3

IUPAC Name:

7-aminonaphthalene-1,3,5-trisulfonic acid

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Name of test material (as cited in study report): FAT 93527/A
- Physical state: Powder
- Analytical purity: approx. 50%
- Lot/batch No.: 0031026A0
- Expiration date of the lot/batch: 10.01.2006
- Storage condition of test material: room temperature
- Solubility: approx. 120 g/L

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
None

Study design

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): Mixture of polyvalent bacteria (activated sludge) collected on May 08, 2001 from the aeration tank of a domestic sewage treatment plant, PRO RHENO Basel communal.
- Preparation of inoculum for exposure: The activated sludge was washed twice with tap water one day before the test was started. Subsequently the sludge was aerated until use. A sample of the activated sludge was taken to determine the dry weight of the suspended solids.
- Concentration of sludge: 0.47 g/L suspended solids The bacteria concentration was obtained by adding 88 mL of the pre-treated sludge (11.4 g/L SS) per 2 l itres test medium.
- Initial cell/biomass concentration: 153.5 and 153.8 mg/L DOC of the test item

Duration of test (contact time):

28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

153.5 mg/L

Based on:

DOC

Initial test substance concentration 2

Initial conc.:

153.8 mg/L

Based on:

DOC

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

DOC removal

Details on study design:

TEST CONDITIONS
- Composition of medium:
Test medium-The mineral salts for each of the following stock solutions were dissolved in 1 litre of distilled water:
Stock solution A
8.5 g of potassium acid phosphate, 21.75 g of di-potassium hydrogen phosphate, 33.4 g of di-sodium hydrogenpnospnate dihydrate and 0.5 g of ammonium chloride.
The pH value of this solution was 7.4.
Stock solution B
36.4 g of calcium chloride dihydrate
Stock solution C
22.5 g of magnesium sulphate heptahydrate
Stock solution D
0.25 g of ferric chloride hexahydrate

10 ml of solution (A) and 1 ml_ of solutions (B), (C) and (D) were added per 1 litre distilled water to form the test medium.

- Test temperature: 20 - 25 °C
- pH: 7.0 - 8.0
- pH adjusted: yes with NaOH
- Suspended solids concentration: 0.47 g/L
- Continuous darkness: yes


TEST SYSTEM
- Culturing apparatus:Glass vessel
- Number of culture flasks/concentration: 2
- Method used to create aerobic conditions: agitated and aerated
- Measuring equipment: TOC/DOC Analyzer SHIMADZU TOC 500


STATISTICAL METHODS: No Statistics applied

Results and discussion

Preliminary study:

None

Test performance:

0% adsorption of FAT 93527/A after 3 hours

% Degradation

Parameter:

% degradation (DOC removal)

Value:

11

Sampling time:

28 d

Details on results:

Adsorption:
0% adsorption of FAT 93527/A after 3 hours

Biodegradation:
11 % biodegradation of FAT 93527/A after 28 days

Total elimination:
(regarding adsorption and biodégradation)
Total elimination of FAT 93527/A after 28 days is 8 %

BOD5 / COD results

Results with reference substance:

Biodegradation of the reference item after 19 days is 99%

Any other information on results incl. tables

None

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

not inherently biodegradable

Conclusions:

11% biodegradation was observed after 28 days.

Executive summary:

FAT 93527/A was tested for inherent biodegradability following OECD test guideline 302 B.

 

Mixture of polyvalent bacteria (activated sludge) collected on May 08, 2001 from the aeration tank of a domestic sewage treatment plant, PRO RHENO Basel communal. The activated sludge was washed twice with tap water one day before the test was started. Subsequently the sludge was aerated until use. A sample of the activated sludge was taken to determine the dry weight of the suspended solids.

 

The day prior to the start of the test, the stock solutions were prepared. The stock solution was diluted 1 : 1 with test water including activated sludge to get the final test concentration of 153.5 and 153.8 mg/L DOC of the test item.

 

A mixture of a total test volume of 2 litres each containing test item, mineral medium and activated sludge was agitated and aerated at 20 - 25 °C in two glass vessels for 28 days. A reference control running in duplicate containing activated sludge, mineral medium and the reference item, and a blank control containing activated sludge and mineral medium were run under the same test conditions. The biodegradation process was monitored by determination of the dissolved organic carbon concentrations (DOC). The ratio of eliminated DOC, corrected for the blank after each time interval, to the initial DOC value was expressed as the percentage biodegradation at each sampling time.

 

Prior to the DOC-determinations the particles of the activated sludge were separated from the samples by centrifugation ( 4000 rpm for 20 minutes). DOC determination was done using TOC/DOC Analyzer (SHIMADZU TOC 500).

 

At the end of the 28day test period 11% Biodegradation of FAT 93527/A was observed.