Pregna-4,6-diene-3,20-dione, 17-(acetyloxy)-6-chloro-1-(chloromethyl)-, (1.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:

June 1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

1992

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

adopted 04 Apr 1984

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: 111 mg were dissolved in 1000 mL tap water under constant stirring for 24 hours. Approximately 500 ml of the solution were filtered through a glassfibre filter. The filtered and unfiltered solutions were filled into the test vessels.
- Eluate: no
- Differential loading: yes
- Controls: yes, test medium control

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Source: Schering AG, Experimental Toxicology
- Age at study initiation (mean and range, SD): 0-24 h

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

20.6 - 21.1 °C

pH:

7.8 - 8.5

Dissolved oxygen:

7.3 - 9.1 mg/L

Nominal and measured concentrations:

100 mg/L nominal
3.9 mg/L according to TOC

Details on test conditions:

TEST SYSTEM
20 Daphnia were used for each test concentration and also for the control group, randomly distributed into groups of five. Labeled 100 mL test vessels were used and filled with 45 mL of the test solution and 5 mL of the dilution water. The vessels of the control group were filled with 50 mL tap water. The test was performed with 4 replicates of each test solution and the dilution water control with 5 Daphnia in each vessel. One additional test vessel for the test concentration and the control group was used without Daphnia for the measurements of pH, temperature and oxygen content. The test started when the animals were added to the previously prepared test solution. The Daphnia were exposed to the test concentration and the control for aperiod of 48 hours under static conditions. The light/dark rhythm was adjusted to 12 hours/12 hours.

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 3.9 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Table 1: Cumulative immobilization (%)

No. of Daphnia	Test concentration of ZK 10882	24 hours	48 hours
20	0,0 mg/I	0	0
20	3,9 mg/L 1) (filtered)	0	0
20	100 mg/L 2) (unfiltered)	0	0

Validity criteria fulfilled:

yes

Conclusions:

The EC50 of 6-Chlor-Chlormethyldien in Daphnia magna is higher than 3.9 mg/L. There was no additional toxicity observed in the unfiltered solution with a nominal concentration of 100 mg/L.

Executive summary:

The purpose of this study was to determine the acute toxicity (immobilization, EC50/48 hours) of the product 6-Chlor-Chlormethyldien with Daphnia magna in a limit test in order to evaluate the aquatic toxicity. Furthermore, it was to be investigated whether an unfiltered solution with test substance containing a precipitate had a higher toxicity than a filtered solution. Twenty Daphnia were used for each test solution and 20 for the control group. The Daphnia were exposed to the test solutions and the dilution water control for aperiod of 48 hours under static conditions. Immobilization was recorded at 24 hours and 48 hours. The organic carbon concentration of the filtered solution was analysed with a TOC-analyzer at 0 and 48 hours and the substance concentration was calculated according to the structural formula . The nominal test concentration of the unfiltered solution was 100 mg/L and the concentration of the filtered solution was 3.9 mg/L. The EC50 of 6 -Chlor-Chlormethyldien in Daphnia magna is higher than 3.9 mg/I. There was no additional toxicity observed in the unfiltered solution with a nominal concentration of 100 mg/L.

Description of key information

The EC50 (48 h) of the test substance in an acute toxicity study against Daphnia is reported to be >4 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

4 mg/L

Additional information

"should read: > 4 mg/L"