3-methylbutan-1-ol

Endpoint summary

Description of key information

Sensitisation data
3-methylbutan-1-ol and pentan-1-ol were found to not be skin sensitising.
Exposure related observations
The nasal pungency threshold of pentan-1-ol was found to be 5.86 mg/L.
3-methylbutan-1-ol was found to be irritating to the throat at a concentration of 0.366 mg/L.
Pentan-1-ol was not irritating to the skin of 30 human volunteers.

Additional information

Sensitisation data (humans)

Data are available obtained in a human maximization test conducted with 3-methylbutan-1-ol (Kligman 1976). In this study, the sensitization to skin was evaluated in 25 human volunteers, who received an application of 8 % 3-methylbutan-1-ol in a 2.5 % aqueous sodium lauryl sulfate solution. The substance was applied via an occlusive patch test to the same site on the volar forearm or back of all subjects for five alternate-day 48 hour periods. Evaluation of the skin sites revealed that none of the 25 individuals showed any signs of sensitization.

Furthermore, publications are available describing the sensitisation potential of 3-methylbutan-1-ol or the read-across substance pentan-1-ol. These studies were included for completeness sake, but it has to be mentioned that the human volunteers described in the publications had been exhibiting dermatitis or skin reactions towards other alcohols before.

In an epicutaneous patch test (Fregert 1963) one volunteer was exposed to 3-methylbutan-1-ol and pentan-1-ol (separate applications) at a concentration of 10 %. Positive skin reactions were found, but the test person had already been exhibiting dermatitis before. In another publication four test persons, also exhibiting dermatitis and positive skin reactions to ethanol, were tested and positive skin reactions were also revealed when testing 3-methylbutan-1-ol or pentan-1-ol (Fregert 1969). A further test person who showed positive skin reactions towards hair lotions was exposed to a series of lower aliphatic alcohols and also to pentan-1-ol in an epicutaneous patch test (Ludwig 1977). No positive skin reactions were revealed for pentan-1-ol.

In another publication two volunteers who had been tested positive for ethanol and acetaldehyde, respectively, were also exhibiting positive skin reactions when exposed to pentan-1-ol at 10 % and 20 % (Stotts 1977).

 

Exposure related observations in humans: other data

In a publication (Nelson 1943) the irritant property of 3-methylbutan-1-ol to the throat was investigated. The concentration at which the vapour caused irritation to the throat was determined to be 100 ppm (corresponding to 0.366 mg/L).

In a further publication (Cometto-Muniz 1990) a study is described which was conducted to assess the odor threshold of 11 chemicals including the test substance. The detection thresholds were measured repeatedly in normosmic and anosmic subjects. The stimuli comprised the first eight members of the series of n-aliphatic alcohols, phenyl ethyl alcohol, pyridine, and menthol. The anosmic subjects were: one male (39 -years-old, nonsmoker, congenital anosmic) and two females (a 35-year-old, nonsmoker, head-trauma anosmic and a 20-year-old, smoker, congenital anosmic). Sessions typically lasted between two and four hours, and they were repeated until 12 thresholds. Recalculation of vapour concentration was performed according to the formula: C (mg/m3) = (molecular weight (g) * C (ppm)) / 24.1 L at 20°C and 1013 hPa (DFG, MAK-Liste).The test substance was detected by all subjects. The average nasal pungency threshold was found to be (± SD): 1603 ± 1.2 ppm equivalent to 5.86 mg/L.

Furthermore, a study report is available evaluating the potential of pentan-1-ol to induce skin irritation. 30 human volunteers were used to apply 0.2 mL of pentan-1-ol on a 25 mm plain Hill Top Chamber containing a Webril pad to the skin of the upper outer arm (Basketter et al. 2004). After an application of 15 and 30 minutes through 1, 2, 3 and 4 hours, pentan-1-ol was found to be not irritating to skin.

One poisoning incident is available for 2 -Metyhyl-1 -Butanol. A 28 year-old male was found in a deep coma complicated with acute respiratory failure because of recreational intoxication. In the case described, the patient ingested an unknown amount of 2 -Metyhyl-1 -Butanol (99% purity) from a 250 mL bottle. The ingestion in a single dose corresponding to the whole volume of the bottle would be equal to 3 g/kg bw (Anand et al. 2014).