7-chloro-5-(2-chlorophenyl)-1,3-dihydro-2H-benzo-1,4-diazepin-2-one 4-oxide

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

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:

2003

Report date:

2003

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

7-chloro-5-(2-chlorophenyl)-1,3-dihydro-2H-benzo-1,4-diazepin-2-one 4-oxide

EC Number:

220-974-2

EC Name:

7-chloro-5-(2-chlorophenyl)-1,3-dihydro-2H-benzo-1,4-diazepin-2-one 4-oxide

Cas Number:

2955-37-5

Molecular formula:

C15H10Cl2N2O2

IUPAC Name:

7-chloro-5-(2'-chlorophenyl)-1,3-dihydro-2H-1,4-benzodiazepin-2-one 4-oxide

Test material form:

solid

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

During the final test duplicate samples for analysis were taken from the filtrate and the control.
Sampling: Frequency: at t=0h and t=48h.
Volume: 10 ml from the approximate centre of the test vessel.
Storage: All samples were stored in a freezer.

Test solutions

Vehicle:

yes

Details on test solutions:

The test solutions were prepared using stock solutions of 100 mg/L by adding quantitatively 100 mg of test substance to 1000 ml ISO-medium. The resulting dispersion was treated with ultrasonic waves for 5 minutes (final study) and magnetically stirred for 3 days (both tests), after which it was ahazy solution with test substance particles, a precipitate and a floating layer. The solution was then filtered through a paper filter (ca. 5 µm, Schleicher and Schuell) to remove the larger undissolved particles. The resulting solution was clear and colourless. Lower test concentrations were prepared by subsequent dilution in test medium (range-finding test). All final solutions were clear and colourless.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

- Common name: Daphnia magna (Straus 1820)
- Source: in-house al culture
- Feeding during test: no

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test conditions

Test temperature:

19.9-20.3

pH:

7.9-8.0

Dissolved oxygen:

8.6-9.0 mg/L

Nominal and measured concentrations:

limit test: 100 mg/L
range-finding test: 0.1, 1.0, 10 and 100 mg/L

Details on test conditions:

Test vessels: 100 ml, all-glass
Medium: ISO, prepared in milli-RO water
Number of daphnia: 20 per concentration
Loading: 5 per vessel containing 80 ml medium
Light: 16 hours photoperiod daily
Feeding: No feeding
Aeration: No aeration of the test solutions.
lntroduction of daphnia: Within 3/4 hours after preparation of the test solutions.

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EL50

Remarks:

loading rate

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 12 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

LNO did not induce acute immobilisation of Daphnia magna at a loading rate of 100 mg/L (NOELR), corresponding to an actual concentration of 12 mg/L (NOEC).

Results with reference substance (positive control):

The reference test was carried out to check the sensitivity of the test system as used by NOTOX. Daphnia were exposed for a maximum of 48 hours to K2Cr2O7 concentrations of 0.1, 0.18, 0.32, 0.56, 1.0 and 1.8 mg/L and to a blank control. Twenty daphnia were exposed per concentration. The 24h-EC50 was 1 .0 mg/L with a 95% confidence interval between 0.94 and 1.2 mg/L. The 48h-EC50 was 0.74 mg/L with a 95% confidence interval between 0.66 and 0.84 mg/L.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the present study LNO did not induce acute immobilisation of Daphnia magna at a loading rate of 100 mg/L (NOELR), corresponding to an actual concentration of 12 mg/L (NOEC).
The EL50 was above a loading rate of 100 mg/L. The EC50 was above the maximum soluble concentration in test medium (> 12 mg/L).