Acrylamide

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Well documented report of a guideline study conducted to GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1991

Report date:

1991

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Acrylamide

EC Number:

201-173-7

EC Name:

Acrylamide

Cas Number:

79-06-1

Molecular formula:

C3H5NO

IUPAC Name:

prop-2-enamide

Details on test material:

- Name of test material (as cited in study report): CT-444-90D
- Substance type: organic
- Physical state: white, flaky, crystalline solid
- Analytical purity: >98.5%
- Impurities (identity and concentrations): water <0.8% , copper sulphate <0.002%
- Composition of test material, percentage of components: 100%
- Purity test date: no data
- Lot/batch No.:
- Expiration date of the lot/batch: no data
- Stability under test conditions: stable
- Storage condition of test material: no data

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Details on inoculum:

- Source of activated sludge: Bergen County, New Jersey, MUA, collected 20/09/90,
- Storage conditions: maintained in an established activated sludge apparatus until test initiation.
- Storage length: 8 days
- Pretreatment: no data
- Concentration of sludge inoculum: 1 mg/l
- Type of filter used: glass of polyester floss

Duration of test (contact time):

28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

1 mg/L

Based on:

ThOD/L

Initial test substance concentration 2

Initial conc.:

2 mg/L

Based on:

ThOD/L

Initial test substance concentration 3

Initial conc.:

5 mg/L

Based on:

ThOD/L

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Stock solution was prepared by adding 2 g of sample to 1 litre of distilled water. The stock solution was screened to determine if it had similar percent carbon content as stated in the formula provided by the supplier. Stock solution was diluted to 100 ppm as carbon after analysis. The diluted stock was then added to BOD bottles at 3.33 ml, 6.67 ml and 16.65 ml to yield test concentrations of 1 mg, 2 mg and 5 mg as carbon, respectively. Test solutions were inoculated with a low concentration of micro-organisms from a mixed population and kept in closed bottles in the dark at a constant temperature of 20±1°C. Degradation was followed by oxygen analyses with the YSI Dissolved Oxygen Analyzer 54A over a 28-day period. Degradability was based on a comparison of readings of actual oxygen demand to the theoretically expected oxygen demand. A parallel control with inoculum, but without test material, was run as a blank correction factor. The procedure was validated by means of a reference substance (aniline, 2 mg/l) of known biodegradability.

Reference substance

Reference substance:

aniline

Remarks:

2 mg/L

Results and discussion

Test performance:

The reference material, aniline, degraded approximately 98% in concurrent testing and was considered "Readily Biodegradable" because it achieved a degradation of greater than 70%. The test system and results are thus considered valid.

% Degradation

% Degradation 1

Parameter:

% degradation (O2 consumption)

Value:

7.4

Sampling time:

5 d

% Degradation 2

Parameter:

% degradation (O2 consumption)

Value:

75.9

Sampling time:

15 d

% Degradation 3

Parameter:

% degradation (O2 consumption)

Value:

100

Sampling time:

28 d

BOD5 / COD results

Results with reference substance:

5 days: 18.5 %
15 days: 66.7 %
28 days: 98.1 %

Any other information on results incl. tables

	% degradation
Sample	5 days	15 days	28 days
1 mg	7.4	100	100
2 mg	7.4	75.9	100
5 mg	7.4	57.0	53.3
Aniline	18.5	66.7	98.1

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The test material was found to degrade approximately 100% in 28 days in the OECD Closed Bottle Test (301D).