2-chloro-2-methylbutane

Short-term toxicity to fish

Administrative data

Endpoint:

short-term toxicity to fish

Type of information:

calculation (if not (Q)SAR)

Adequacy of study:

supporting study

Study period:

2007

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with limited documentation / justification

Data source

Reference

Reference Type:

publication

Title:

QSAR Models for Predicting in Vivo Aquatic Toxicity of Chlorinated alkanes to Fish

Author:

Elton Zvinavashe, Hans van den Berg, Ans E. M. F. soffers, Jacques Vervoort, Andreas Freidig, Albertinka J. Murk, and Ivonne M. C. M. Rietjens

Year:

2008

Bibliographic source:

Chem. Res. Toxicol. 2008, 21, 739-745

Materials and methods

Test guideline

Guideline:

other: development of a QSAR model for chlorinated alkanes

Principles of method if other than guideline:

Development of an QSAR model for prediction of in vivo aquatic toxicity of chlorinated alkanes to fish. The model is based on in vitro data and on in silico logKow data. The model was validated internally and externally with five additional compounds. The in vitro data from MTT assays and the in vivo toxicity data showed a correlation. The model is applicable to chlorinated alkanes up to C10 and up to 8 chlorine atoms with an logKow value between 1.71 and 5.70.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

2-chloro-2-methylbutane

EC Number:

209-836-2

EC Name:

2-chloro-2-methylbutane

Cas Number:

594-36-5

Molecular formula:

C5H11Cl

IUPAC Name:

2-chloro-2-methylbutane

Test organisms

Test organisms (species):

Poecilia reticulata

Details on test organisms:

Poecilia reticulata (guppy) was chosen as experimental in vivo data were available.

Study design

Test type:

other: QSAR

Total exposure duration:

7 d

Results and discussion

Effect concentrations

Key result

Dose descriptor:

other: log LC50

Effect conc.:

2.18 µmol/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks on result:

other: QSAR

Remarks:

prediction of in vivo log LC50 [µM) to the fish (Poecilia reticulata)

Details on results:

The developed QSAR model is applicable for chlorinated alkanes with up to 10 carbon and eight chlorine atoms and a logKow of 1.71 and 5.70. The in silico calculated logKow of the test substance was 2.92 and has been used in the model to predict the acute toxicity of the test substance to fish. A exposure duration is not explicitly mentioned, the available experimental test data indicates a test duration of 7 days for Poecilia reticulata.
The strong correlation between toxicity and hydrophbicity indicates a nonpolar narcotic mechanism of action for chlorinated alkanes.

Applicant's summary and conclusion

Conclusions:

A model to predict the in vivo acute toxicity to fish for chlorinated alkanes has been developed. The logLC50 of the test substance was predicted to be 2.18 µM.