19-Norpregn-5(10)-ene-21-nitrile, 17-hydroxy-3-oxo-, (17.alpha.)-

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Dec 2002 - Jan 2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Principles of method if other than guideline:

not relevant

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

no

Test organisms (species):

Daphnia magna

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 20.8 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: Saturated solution

There was no substance related immobilization. The single immobilized Daphnia in the control group is within the limit (10%) accepted by the OECD guideline.

Validity criteria fulfilled:

yes

Conclusions:

The EC50/48 hours of ZK 37877 to Daphnia magna is expected to be higher than a saturated solution (20.8 mg/L, as determined by TOC analysis).

Executive summary:

The purpose of the study was to determine the acute toxicity (immobilization, EC50/48 hours) of 5 -Dehydrocyanomethylketon (ZK 37877) with Daphnia magna in order to evaluate the aquatic toxicity. ZK 37877 is an intermediate of the synthesis of dienogest. The study was conducted as a limit test according to the following guidelines ofthe OECD, no 202.

20 juvenile Daphnia magna were used for the test solution and 20 for the tap water control. The Daphnia were exposed for a period of 48 hours under static conditions. Immobilization was recorded at 24 hours and 48 hours. For the preparation of the test solution, a suspension with a nominal loading of 125 mg/L was stirred for 24 hours after ultrasonification. This suspension was filtered through a glassfibre filter. The solution obtained by this procedure was used for the test solution. It was considered to be saturated under the conditions of this test. The organic carbon concentration of the test solution was analyzed with a TOC analyzer with samples taken at the start of exposure and 48 hours thereafter. The substance concentration was calculated on the basis of the molecular formula. The mean concentration was calculated with 20.8 mg/L.

There was no substance related immobilization.

Description of key information

The EC50/48 hours of ZK 37877 to Daphnia magna is expected to be higher than a saturated solution (20.8 mg/L, as determined by TOC analysis).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

> 20.8 mg/L