Dichlorodicyclopentylsilane

Short-term toxicity to fish

Administrative data

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2000-02-15 until 2000-05-09

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD study under GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2000

Report date:

2000

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Reference

Name:

Unnamed

Type:

Constituent

Details on test material:

- Name of test material (as cited in study report): Silane CP 2
- Physical state: liquid
- Analytical purity: 96.3% (GC)
- Impurities (identity and concentrations): as stated in substance data
- Composition of test material, percentage of components: as stated in substance data
- Purity test date: 1999-10-29
- Lot/batch No.: 10466 QB
- Expiration date of the lot/batch: 2002-10-29
- Stability under test conditions: reaction to hydrolysis product
- Storage condition of test material: in original container, at room temperature, in the dark

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Duplicate samples from the freshly prepared test media of all test concentrations and the control were taken at the start of the test (6.5 hours after test media preparation). For the determination of the stability of the test item under the test conditions, respectively the maintenance of the test item concentrations during the test period, samples were taken in duplicate out of all test media and the control on day 2 and day 4 of exposure. From the test item concentration of nominal 100 mg/L only stability samples were taken in duplicate after 24 hours test duration, since all fish were already dead after 24 hours.
The samples were stored in the refrigerator and protected from light until analysis were performed.
In parallel to the test start stability samples were prepared. A stock solution of the test item was prepared in acetone. This stock solution was used to fortify samples of the test water at the level of 5, 20 and 100 mg test item/L test water.

Test solutions

Vehicle:

no

Details on test solutions:

Adequate amounts of the test item were mixed into small amounts of test water by ultrasonic treatment for 2 x 15 minutes and intense stirring for approx. 15 minutes. Then, the suspensions were filled into aquaria and were filled up with test water to prepare the desired test concentrations. The main part of the test item react within 6 hours to the hydrolysis product dicyclopentylsilanediol. Therefore, the test media were prepared 6.5 hours before introduction of test fish (= start of the test).

Test organisms

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

The test fish were obtained from City Zoo, 64283 Darmstadt, Germany.
Male and female Zebra fish (Brachydanio rerio)
Age and size: juveniles; mean body length in the test was 3.06+/- 0.21 cm, the mean body wet weight was 0.28 +/- 0.05 g

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

not applicable

Test conditions

Hardness:

2.5 mmol/L (= 250.0 mg/L) as CaCO3

Test temperature:

21 °C

pH:

7.1 to 8.1

Dissolved oxygen:

at least 7.8 mg/L or higher

Nominal and measured concentrations:

Nominal: 4.6, 10, 21, 46, 100 mg/L
Measured: -, -, 19.5, 41.2; 77.8 (part of the test item lying on the bottom) mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: 25 litre glass aquaria with 10 litre test medium
- Aeration: slightly during test
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: reconstituted water in accordance with Guidelines
- Ca/mg ratio: 4:1
- Alkalinity: 0.8 mmol/L


OTHER TEST CONDITIONS
- Photoperiod: 16 h light : 8 h dark
- Light intensity: 670 - 920 lux


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Observation approx. 2, 24, 48, 72 and 96 hours test duration

Reference substance (positive control):

not required

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

49.3 mg/L

Nominal / measured:

nominal

Conc. based on:

dissolved

Remarks:

hydrolysis product

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CI: 32.0 mg/L to 75.9 mg/L

Effect concentrations 2

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

21 mg/L

Nominal / measured:

nominal

Conc. based on:

dissolved

Remarks:

hydrolysis product

Basis for effect:

mortality (fish)

Remarks:

; symptoms of intoxication

Reported statistics and error estimates:

The LC 50 and the 95 % confidence limits were calculated by Moving average interpolation.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Substance is harmful to fish.

Executive summary:

The objective of this 96-hour study was to evaluate the acute toxicity of the test item to fish. The test has been performed in accordance with EEC-/OECD Guideline under GLP. Due to hydrolytical reaction of the test item in water the hydrolysis product dicyclopentylsilanediol was tested. An LC50 (96 h) of 49.3 mg/L has been determined. The NOEC in this test was 21 mg/L.