Benzeneacetyl chloride, 2,5-dimethyl-

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:

15 Aug - 07 Dec 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

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 105.0 mg of the test item were added to 1 litre of dilution water, treated for 1 hour in an ultrasonic bath and then stirred for 24 h 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):

Daphnia magna

Details on test organisms:

Common name: water flea
Source: Strain of Bundesgesundheitsamt Berlin
Maintenance and Acclimatisation:
A population of parthenogenetic females of synchronized age structure is maintained since more than 15 years in the test facility under constant temperature conditions (20 +/- 1 °C) at a 16 : 8 hour light-dark photoperiod (illumination: < 1000 lux).

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

The hardness of the dilution water used was 15.4 °dH (= 274.89 mg/L CaCO3).

Test temperature:

20.2 °C

pH:

8.0

Dissolved oxygen:

8.8 mg/L

Nominal and measured concentrations:

nominal: 100 mg/L
measured: 99.1 mg/L (0 h), 98.8 mg/L (48 h)

Details on test conditions:

Test vessels: 50 ml glass beakers holding 10 neonates in 20 mL of test medium
Experimental design: 1 test concentration plus 1 control1; 0 neonates per vessel, 2 replicates per concentration/control; no feeding during the exposure period;
Photoperiod: 16 h light: 8 h dark
Aeration: none
Criteria of effects: The criterion of adverse effects used in this study was the item-induced alteration of the normal mobility behaviour and the loss of locomotory actions of the neonates, observed at 24 and 48 hours

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

No toxic effects against daphnia at a test concentration of 100 mg/1. The results are expressed in terms of nominal concentrations. Recovery rates correspond to 99.1% of nominal values at 0 hours, and to 98.8% of nominal values at 48 hours, respectively.

Validity criteria for the measurement of the daphnia toxicity:

Target condition according to guideline:	Actual condition according to the study:	Validity criteria met:
Young daphnids, aged less than 24 hours at the start of the test, are exposed to the test substance at a range of concentrations for a period of 48 h.	Age of daphnids used: neonates Exposure time: 48 h	Yes
In the control, including the control containing the solubilising agent, not more than 10 % of the daphnids should have been immobilized. (Not more than 10 % of the control daphnids should show immobilisation or other signs of disease or stress, for example, discoloration or unusual behaviour such as trapping at surface of water)	In the controls, no immobilisation of the daphnids occured.	Yes
Test concentrations: At least five test concentrations should be used. They should be arranged in a geometric series with a separation factor preferably not exceeding 2.2. The highest concentration tested should  preferably result in 100 % immobilization, and the lowest concentration tested should preferably give no observable effect.	Test was a limit test (conc. used was 100 mg/L).	Not applicable

 

Validity criteria fulfilled:

yes

Remarks:

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

Conclusions:

No toxic effects against daphnia at a test concentration of 100 mg/1. The results are expressed in terms of nominal concentrations. Recovery rates correspond to 99.1% of nominal values at 0 hours, and to 98.8% of nominal values at 48 hours, respectively.

Executive summary:

A study was performed to assess the acute toxicity to Daphnia magna STRAUS under static conditions.

The study was conducted in accordance with the OECD Guideline for Testing of Chemicals No. 202 'Daphnia sp., Acute Immobilisation Test' (adopted April 13, 2004) which is in most parts equivalent to the EEC Methods for Determination of Ecotoxicity Annex to Directive 92/69/EEC (OJ. No. L383A, 29.12.92) Part C, Method 2 Acute toxicity for Daphnia'.

The Daphnia 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 and a magnetic stirrer.
Observations were made on the swimming ability and the immobilisation rate, respectively, after 24 and 48 hours of exposure. The following values were determined:

Time  [h]	EC 50 [mg/L]
24	> 100
48	> 100

No toxic effects against daphnia at a test concentration of 100 mg/L.

The results are expressed in terms of nominal concentrations. Recovery rates correspond to 99.1% of nominal values at 0 hours, and to 98.8% of nominal values at 48 hours, respectively.

Description of key information

No toxic effects against daphnia at a test concentration of 100 mg/1.The results are expressed in terms of nominal concentrations. Recovery rates correspond to 99.1% of nominal values at 0 hours, and to 98.8% of nominal values at 48 hours, respectively.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

> 100 mg/L