Fusel oil

Short-term toxicity to aquatic invertebrates

Description of key information

EC50 (48 h) > 173 mg/L

Additional information

Studies on the acute toxicity to invertebrates are available for two of the four main constituents of Fusel oil.

The key study available for 2 -Methylbutanol (CAS No. 137-32-6) was conducted according to the OECD Guideline 202 under GLP conditions (BASF, 2011). Therefore, waterflea (Daphnia magna) were exposed for 48 h under static conditions to a nominal test concentration of 120 mg/L in a limit test. The test concentration was analytically verified, resulting in a mean measured test concentration of 173 mg/L. No mortality or other adverse effects could be observed at the end of the exposure period. Therefore, an EC50 value could not be calculated and it is considered to be > 173 mg/L (mean measured).  

The key study carried out with Ethanol (CAS No. 64-17-5), was performed following the guideline ASTM E729-80 under non-GLP conditions (Takahashi et al., 1987). Daphnids (Ceriodaphnia dubia) were exposed in a static system over a period of 48 h to different concentrations in a dose-response test. The EC50 -value was determined to be 5012 mg/L based on nominal concentrations.

Further supporting studies are available for Ethanol (CAS No. 64-17-5) on different freshwater and marine invertebrate species, and all indicate low acute toxicity of the substances to invertebrates.

As no experimental results on the acute toxicity to invertebrates are available for 3-Methylbutanol (CAS No. 123-51-3) and 2-Methylpropanol (CAS No. 78-83-1) QSAR-calculations were performed for these constituents as well as for the remaining two major ones. The EC50 (48 h) values determined by using ECOSAR v1.00 as well as the experimental results are presented in the following table.

 

Constituent of Fusel oil	CAS-No.	EC50 [mg/L]	Reference
Ethanol	64-17-5	5012	Takahashi et al. 1987
		1117.1	ECOSAR v1.00
2 -Methylpropanol	78-83-1	326.14	ECOSAR v1.00
3 -Methylbutanol	123-51-3	154.20	ECOSAR v1.00
2 -Methylbutanol	137-32-6	> 173	BASF SE 2011
		154.20	ECOSAR v1.00

 

The QSAR data indicate low toxicity of all main constituents to aquatic invertebrates. They also demonstrate the similarity of the toxic potential between the two isomers 3 -Methylbutanol and 2 -Methylbutanol, and that 2-methylpropanol is expected to be even less toxic. The available data is thus considered to adequately describe the toxicity of all main constituents.

Concluding from the results reported for the main constituents Ethanol, 2-Methylpropanol, 2-Methylbutanol and 3-Methylbutanol, no short-term effects of Fusel oil on invertebrates are expected.