Reaction mass of 2-ethylhexyl (6-isocyanatohexyl)-carbamate and bis(2-ethylhexyl) 1,6-hexan-1,6-diylbiscarbamate

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:

2000

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

no

Remarks:

Test performed between 2000 - 2001, a re-evaluation was carried out in 2009.

Analytical monitoring:

no

Details on sampling:

Sampling schedule:
- Control: at 48 hours
- Test concentration: 100 mg/L at 0 and 48 hours

Vehicle:

no

Details on test solutions:

A stock solution of the test item was prepared at a concentration of 100 mg/L. The test solution was treated for 60 seconds with an ultra turrax, stirring for 24 hours and filtered (folded filters with pore size 7-12 µm to exclude undissolved test item. The test was carried out by Water Accommodated Fraction (WAF).

Test organisms (species):

Daphnia magna

Details on test organisms:

- Source: Strain of Bundesgesundheitsamt Berlin
- Maintenance and Acclimatisation: A population of parthenogenetic females of synchronized age structure has been maintained for more than 15 years in the test facility under constant temperature conditions (20 +/- 1 °C) at a 16 : 8 hour light-dark photoperiod (light intensity: < 20 μE x m-2 x s-1). The culture water (so-called 'M4 medium') was partly renewed once a week. The Daphnia were exclusively fed unicellular green algae (Desmodesmus subspicatus) 'ad libitum'. Mortalities of parent Daphnia during the culture period were recorded daily in a semi-quantitative way. The neonates were separated from their parent Daphnia by filtration prior to the acute test.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

No data

Test temperature:

19.8 °C

pH:

7.6

Dissolved oxygen:

8.8 mg/L

Salinity:

n.a.

Nominal and measured concentrations:

A Water Accommodated Fraction (WAF) was used to test effects at a limit effective loading of 100 mg/L and no specific analysis was performed.

Details on test conditions:

Pre-TREATMENT OF TEST ITEM AND PREPARATION OF TEST ITEM CONCENTRATIONS:
- To produce the only Water Accommodated Fraction (WAF) the test solution was treated for 60 seconds with an ultra turrax, stirring for 24
hours and filtered (folded filters with pore size 7-12 µm) to exclude undissolved test item

EXPOSURE CONDITIONS:
- Test vessels: cylindrical glass test vessel holding 1 0 neonates in 20 mL of test medium
- Experimental design: 1 test concentration plus 1 control, 10 neonates per vessel, 2 replicates per concentration/control, no feeding during the exposure period
- Method of initiation: neonates were placed in prepared media
- Photoperiod: 16 h light : 8 h dark
- Aeration: none
- Test item concentration: 100 mg/L
- Method of administration: direct weighing
- Medium renewal: 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 motor actions of the neonates, observed at 24 and 48 hours.

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EL0

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

behaviour

Key result

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

behaviour

Duration:

24 h

Dose descriptor:

EL0

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

behaviour

Details on results:

The results are expressed in terms of nominal concentrations.

Validity criteria fulfilled:

yes

Remarks:

(Immobilisation and other abnormalities in the controls did not exceed 10 % by the end of the test; dissolved oxygen concentration remained above 3 mg/L throughout the exposure period)

Conclusions:

After 48 hrs an EL-50 of higher than 100 mg/L was measured. The result is expressed in terms of Effective Loadings (EL). No toxic effects against Daphnia were observed at a limit test concentration at the limit of water solubility under exposure conditions.

Executive summary:

The method described in the Council Regulation (EC) No 92/69, Method C.2 'Acute toxicity for Daphnia' (1992) is equivalent to OECD Guideline for Testing of Chemicals No. 202 'Daphnia sp., Acute Immobilisation Test'. The purpose of this method was to determine that concentration which causes a 50 % immobilisation rate or, if conducted as a limit test, to determine the acute toxic effects at a maximum test concentration of 100 mg/L or at the limit of water solubility, respectively. ln the test, Daphnia were exposed to the test item added to water at a limit test concentration of nominally 100 mg/L for a period of 48 hours. At this concentration no toxic effects against Daphnia were observed at the end of the 48 hour study period, thus no statistical analysis was required to determine the EL50. Immobilisation rates were recorded at 24-hour intervals. Additionally any abnormal behaviour or appearance of the Daphnia was reported every 24 hours. During the test a temperature range of 19.8 - 20 °C was maintained in the test vessels, with a maximum temperature fluctuation of +/- 1 °C in each individual test. The pH and oxygen values were measured at the end of the test. The test was conducted as a static test. After 48 hrs an EL-50 of higher than 100 mg/L was measured and the result is expressed in terms of Effective Loadings (EL).

This toxicity study is classified as acceptable and satisfies the guideline requirements for the acute Daphnia study.

Description of key information

After 48 hrs an EL-50 of higher than 100 mg/L was measured. The result is expressed in terms of Effective Loadings (EL). No toxic effects against Daphnia were observed at a limit test concentration at the limit of water solubility under exposure conditions (Shi, 2009).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

"Should read > 100 mg/L"

A Water Accommodated Fraction (WAF) was used to test effects at a limit effective loading of 100 mg/L and no specific analysis was performed.