3,3-dimethylbutyne

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:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Well documented study according to internationally accepted guidelines but not GLP compliant.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Remarks:

The concentrations of test substance were not analysed in this study. Only nominal concentrations were used.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

3,3-dimethylbutyne

EC Number:

213-035-3

EC Name:

3,3-dimethylbutyne

Cas Number:

917-92-0

Molecular formula:

C6H10

IUPAC Name:

3,3-dimethylbut-1-yne

Test material form:

gas under pressure: refrigerated liquefied gas

Details on test material:

Test item: 3,3-dimethylbutyne
CAS No. 917-92-0
Batch No. L37038N
Physical state Clear, transparent, liquid
Colour Colourless
Active ingredient content (GC) 97.5%
Storage 2-8°C in a tightly closed container

Sampling and analysis

Analytical monitoring:

no

Details on sampling:

At 24 and 48 hours after the start of the test the percentage of the immobilised daphnids were determined.

Test solutions

Vehicle:

yes

Details on test solutions:

The test organism was breaded and hold in Elendt M4 medium wich was used also for preparing of test item stock and working solutions.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Test species: Daphnia magna Straus
Age: <24 hours neonates
Young daphnids were used in the test should have been less than 24 hours old and were not first brood progeny.
Source: National Institute of Environmental Health

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test conditions

Test temperature:

21+/-1°C

pH:

The pH was measured in the beginning and in the end of the test. The pH values of test solutions were not adjusted in the beginning of the test.

Dissolved oxygen:

Dissolved oxygen values were measured in the beginning and in the end of the test.

Nominal and measured concentrations:

The following concentrations were applied: 5.0; 7.5; 15.0; 30.0; 60.0; 100 and 150 mg/L.
The evaluation of the effects was based on the nominal concentrations of test item.

Details on test conditions:

At each concentration level four replicates were used. Each replicate contained 5 daphnids in 90 ml test solution. The test vessels were closed tightly and were kept in a thermostat at 21+-1°C.with a 16/8 hours light/dark cycle. The treatment of control vessels were the same as test vessels. The pH and oxygen concentrations were measured in the beginning and in the end of the test. The number of immobilised daphnids were counted 24 and 48 hours after the start of the test.

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

26.16 mg/L

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

42.71 mg/L

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL

Details on results:

The statistical analyses of data were performed by ToxRat software.
The NOEC and LOEC were determined with Fisher's exact binomial test with Bonferri correction. The results were inconclusive.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

In this Daphnia magna Acute Immobilisation Test for 3,3-dimethyl-1-butyne (CAS No. 917-92-0) the results indicated that the test item is hazardous to the aquatic environment [GHS Acute aquatic hazard Category Acute III] - 48 hr EC50 for Crustacea) > 10 mg/L but <= 100 mg/L]