Benzeneacetyl chloride, 2,5-dimethyl-

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

31 Jul - 15 Dec 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

1992

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

Analytical Procedure - Standard Solutions used for Calibration
20.5 mg of the test item were dissolved in Acetonitrile and made up with Acetonitrile to the mark in a 100 mL volumetric flask to prepare a stock solution of 205 mg/L.
Defined volumes of this stock solution were diluted with Milliporewater to obtain standard solutions in the range of 0.041 to 4.10 mg/L.
Although the overall method sensitivity may be better, the concentration of the lowest used calibration solution is employed as the limit of quantification.
These solutions were used to calibrate the HPLC-system.

Vehicle:

no

Details on test solutions:

To produce the only test concentration 501.6 mg of the test item were added to 5 litres of dilution water, then treated in an ultrasonic bath for 60 minutes and afterwards stirred for 24 hours on a magnetic stirrer. Finally undissolved particles of the test item were removed by filtration using a folded filter of pore size 7-12 µm.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

Name: Zebra fish
Source: Aqua KlöGer (Germany)
Date supplied: 2006-10-24
Acclimatisation: Stock held since 2006-10-24 and acclimatised to the test conditions since then.
Temperature: 20 - 24 °C
Dissolved oxygen: > 5 mg/L
Feeding: Commercial fish food, daily. Discontinued 24 h prior to test.
Mortalities during acclimatisation period: < 5 %
Medication: none

Mean standard length (n = 20): 3.6 cm (S.D. = 0.21 cm)

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Test temperature:

21.5 - 22.4 °C

pH:

7.7-7.8

Dissolved oxygen:

8.7 - 9.0 mg/L

Nominal and measured concentrations:

nominal: 100 mg/L
measured: 84.3 mg/L (0 h) and 85.4 mg/L (96 h)

Details on test conditions:

Test vessels: glass aquaria holding 5 L of test media
Experimental design: 1 test concentration plus 1 control10 animals per test concentration no feeding during the exposure period static system
Method of initiation: animals were placed in prepared media
Loading: 0.75 g body weight (wet weight) per litre
Photoperiod: 16 h light: 8 h dark
Temperature: mean +/- 1 °C (in the temperature range 20 - 24 °C)
Aeration: gentle aeration via narrow glass tubes
Test item concentration: 100 mg/L
Method of administration: direct weighing
Medium renewal: none
Duration of exposure: 96 hours
Criteria of effects: The criterion of death used in this study was the absence of response to physical stimulation. In addition to observations on mortality at 2, 24, 48, 72and 96 hours, subjective assessments were made on the type and incidence of sub-lethal effects compared with control fish.

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

No toxic effects against fish were observed at a test concentration of 100 mg/L under static test conditions. All results are expressed in terms of nominal concentrations. Recovery rates corresponds to 84.3 % of nominal value at 0 hours and to 85.4 % of nominal value at 96 hours, respectively.

Sublethal observations / clinical signs:

Validity criteria for the measurement of the short-term toxicity to fish:

Target condition according to guideline:	Actual condition according to the study:	Validity criteria met:
In the control(s) (dilution water control, solvent control), the mortality should not exceed 10% (or one fish, if fewer than 10 control fish are tested) at the end of the exposure.	Mortaility of zebra fish in the control was 0 after 96h.	Yes
The dissolved oxygen concentration should be ≥60 % of the air saturation value in all test vessels throughout the exposure	Oxygen saturation ranged beween 96 - 101 % in the tests.	Yes
All fish should be held in the laboratory for at least 9 days before they are used for testing. The first 48 hours constitute a settling-in period. Then, fish should be acclimatised for at least 7 days (48 hours settling-in + 7 days acclimatisation = 9 days) in water similar to test water immediately before the start of the test.	Stock held since Oct. 24, 2006 and acclimatised to the test conditions since then. Test was performed 31 Jul - 15 Dec 2006.	Yes
During the acclimatisation period, mortalities are recorded, and the following criteria are applied:    - mortalities of greater than 10% of the population in seven days: reject the entire batch;    - mortalities between 5 and 10% of the population: acclimatisation is continued for seven additional days; and if there is more than 5% mortality during the second seven day period, reject the entire batch;    - mortalities of less than 5% of population in seven days: accept the batch.	Mortalities during acclimatisation period: < 5 %	Yes
Duration: 96 hours.	Duration was 96 h.	Yes
The water temperature should not differ by more than 2 °C.	Test temperature was: 21.5 - 22.4 °C.	Yes

 

Validity criteria fulfilled:

yes

Remarks:

See 'Any other information on results incl. tables'.

Conclusions:

No toxic effects against fish were observed at a test concentration of 100 mg/L under static test conditions. All results are expressed in terms of nominal concentrations. Recovery rates corresponds to 84.3 % of nominal value at 0 hours and to 85.4 % of nominal value at 96 hours, respectively.

Executive summary:

The study was conducted in accordance with EEC Methods for Determination of Ecotoxicity Annex to Directive 92/69/EEC (OJ. No. L383A, 29.12.92) Part C, Method 1 'Acute toxicity for Fish' which is in most parts equivalent to the OECD Guideline for Testing of Chemicals No. 203 'Fish, Acute Toxicity Test'.

Groups of ten fish of the recommended size were exposed to a limit test concentration of nominally 100 mg/L test item dissolved in water. Auxiliaries used to prepare the test media were an ultrasonic bath, a magnetic stirrer and a folded filter. Observations were made on the number of dead fish and the incidence of sub-lethal effects after 2, 24, 48, 72 and 96 hours of exposure.

The following values were determined:

Time [h]	LC50 [mg/L]
2	> 100
24	> 100
48	> 100
72	> 100
96	> 100

No toxic effects against fish were observed at a test concentration of 100 mg/1 under static test conditions.

All results are expressed in terms of nominal concentrations. Recovery rates corresponds to 84.3 % of nominal value at 0 hours and to 85.4 % of nominal value at 96 hours, respectively.

Description of key information

No toxic effects against fish were observed at a test concentration of 100 mg/L under static test conditions. All results are expressed in terms of nominal concentrations. Recovery rates corresponds to84.3 % of nominal value at 0 hours and to 85.4 % of nominal value at 96 hours, respectively.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

> 100 mg/L