CASRN 64-15-5, 67-56-1, 75-65-0
Ethanol, methanol, and tert-butyl alcohol are all clear, colorless liquids. Tert-butyl alcohol can form crystals. Ethanol has a mild order, like wine or whiskey, methanol has an alcohol odor – slightly more pungent than ethanol, and tert-butyl alcohol has a camphor-like odor. All three compounds are very soluble in water. The odor threshold for ethanol is reported to be 10 part per million (ppm). The odor threshold for methanol is reported to be 100 ppm. The odor threshold for tert-butyl alcohol is about 75 ppm.
Most ethanol is used in alcoholic beverages in a variety of dilutions. Other uses for ethanol are as a solvent, in the manufacture of denatured alcohol, in pharmaceuticals, in perfumery, in organic synthesis, as an octane booster in gasoline, and as a significant portion in some automobile fuels. Methanol is used as an industrial solvent, as a raw material for making formaldehyde and methyl esters of organic and inorganic acids, as an antifreeze for automotive radiators and brakes, as an octane booster in gasoline, and as an extractant for animal and vegetable oils. Tert-butyl alcohol is use to separate water from substances, in the manufacture of flotation agents (for mining) and in flavors, as a solvent in paint removers, and as an octane booster in gasoline.
Sources of Exposure in Iowa
The general population is exposed to ethanol through the consumption of alcoholic beverages. Exposure to ethanol through inhalation and dermal contact will occur in workers at industries that manufacture ethanol. Exposure to ethanol will occur from exposure to gasoline that contains ethanol. Exposure to methanol will occur in workers in industries that manufacture and use methanol as a solvent. The general population may be exposed to small amounts of methanol in outside air, and in the food and water that they drink. The majority of exposure to tert-butyl alcohol will occur in industries that utilize it as a solvent or as a component in solvents.
Health Effects from Large Acute Exposures
The health effects from exposure to large short-term exposure to ethanol and other alcohols (methanol and tert-butyl alcohol) have been well-documented. Ethanol and other alcohols are central nervous system depressants and exposure to large amounts causes impaired judgment, decreased reaction time, confusion, stupor, coma, and possible death. Exposure to high levels of methanol can also cause partial to total blindness. Tert-butyl alcohol is more slowly metabolized than ethanol and methanol, so the health effects are more persistent.
Health Effects from Smaller Chronic Exposures
Chronic or long-term exposure to lower levels of ethanol and other alcohols can cause kidney, liver, and heart damage. Exposure to skin can cause redness and irritation. There is not enough information to classify ethanol, methanol, and tert-butyl alcohol as carcinogenic.
Protection from Exposure
Limiting the consumption of alcoholic beverages is the most effective method to be protected from exposure to ethanol and other alcohols. Respiratory protection and dermal protection should be worn when handling large amounts of alcohols in an industrial setting.
Internet Links to Further Information:
Information from EPA IRIS DatabaseThe Integrated Risk Information System (IRIS) database is an EPA database of human health effects that may result from exposure to various environmental substances. The IRIS database contains information on methanol.
TOXNETTOXNET (Toxicology Data Network) is a cluster of databases covering toxicology, hazardous chemicals, environmental health and related areas. It is managed by the Toxicology and Environmental Health Information Program (TEHIP) in the Division of Specialized Information Services (SIS) of the National Library of Medicine (NLM). After accessing the Internet link above, enter the word, “ethanol”, “methanol”, or “tert-butyl alcohol” within the search box to find further information on these chemicals.
NIOSH Pocket Guide for Chemicals
This guide is a source of general industrial hygiene information on several hundred chemicals/classes for workers, employers, and occupational health professionals. Ethanol Methanol tert-butyl alcohol