(17ß)-3-Hydroxyestra-1,3,5(10)-trien-17-yl acetate

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

(17β)-3-Hydroxyestra-1,3,5(10)-trien-17-yl acetate

EC Number:

605-722-5

Cas Number:

1743-60-8

Molecular formula:

C20H26O3

IUPAC Name:

(17β)-3-Hydroxyestra-1,3,5(10)-trien-17-yl acetate

Test material form:

solid: crystalline

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Details on inoculum:

Type of inoculum: aerobic mixed bacterial culture
Source: Municipal wastewater treatment plant, Esztergom-Kertváros

Duration of test (contact time):

28 d

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Preparation of inoculum test culture:
Before the test 300 ml stock culture was filtered through a filter with 0.2 mm pore size to remove the bigger insoluble particles and then the dry substance content of the filtrate was determined. The measured value was 6.40 g/L. For preparing the inoculum culture 168.75 ml mineral medium was added to 31.25 ml filtered stock culture. The calculated dry mass of inoculum culture was 1 g/L.


Preparation of reference solution:
For the reference solution 320.17 mg sodium acetate was diluted in 100 ml mineral medium.

Preparation of test vessels:
Following test vessels were prepared and analysed for the study:
- Test item (in two replicates)
- Blank control (in two replicates)
- Reference solution (positive control)
- Reference and test item solution (toxicity control)
- Sterilized solution of test item (abiotic control)

Reference substance

Reference substance:

acetic acid, sodium salt

Results and discussion

% Degradation

Key result

Parameter:

% degradation (O2 consumption)

Value:

58

Sampling time:

28 d

Remarks on result:

other: mean of two replicates

Details on results:

According to OECD guideline the test item should be classified as readily biodegradable if the percentage biodegradation reaches 60% of theoretical oxygen demand within 28 day period in a 10-day window.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

The biodegradability of Estradiol-17ß-acetate was investigated in Ready Biodegradability – Manometric respirometry test (according to OECD 301 F guideline). According to OECD guideline the test item should be classified as readily biodegradable if the percentage biodegradation reaches 60% of theoretical oxygen demand within 28 day period in a 10-day window. Based on ready biodegradability testing results the Estradiol-17ß-acetate is not readily biodegradable.