From: kral@hplabsz.hpl.hp.com (Joseph Kral)
Subject: description of alcohols
Date: Fri, 8 Jan 1993 22:37:03 GMT
Organization: Hewlett-Packard Laboratories Palo Alto,CA



With all the talk of distilling and going blind etc.... I thought I'd post 
some information about the three most common alcohols.  I've included 
synonyms so when someone says ispropyl, we all will know that its the same
as 2-propanol for instance.



Excerpted from:
Chemical Hazards of the Workplace, second ed. 1988

Methyl alcohol
CH3OH

Synonyms:
	Methanol; wood spirit; carbinol; wood alcohol; wood naphtha; methylol;
	Columbian spirit; colonial spirit

Uses:
	Production of formaldehyde; paints, varnishes, cements, inks, and
	dyes

Exposure: 
	Inhalation; skin absorption

Toxicology:
	Methyl alcohol causes optic neuropathy, metabolic acidosis, and
	repiratory depression.
	Although methyl alcohol poisoning has occurred primarily from the
	ingestion of adulterated alcoholic beverages, symptoms can also
	occur from inhalation or absorption through the skin.  Impairment
	of vision and death from absorption by the latter routes have been
	reported in the older literature.  Typically, within 18 to 48 hours
	after ingestion, patients develop nausea, abdominal pain, headache,
	and abnormally slow deep breathing.  This is accompanied by visual
	symptoms ranging from blurred or double vision and changes in color
	perception to constricted visual fields and complete blindness.
	The most severely poisoned patients become comatose and may die;
	those who recover from coma may be found blind.  One of the most
	striking features of methyl alcohol poisoning is acidosis; the
	degree of acidosis has been found to closely parallel the severity
	of poisoning.  Accumulated evidence suggests that chronic exposure
	to 1200 to 8300 ppm can lead to impaired vision. Exposure to vapor
	concentrations ranging from 365 to 3080 ppm resulted in blurred
	vision, headache, dizziness, and nausea.
	The liquid in the eyes has caused superficial lesions of the cornea
	that were of a nonserious nature. Prolonged or repeated skin contact
	will cause dermatitis, erythema, and scaling.
	The presence of an asymptomatic latent period following ingestion
	suggests that methyl alcohol needs to be metabolized before
	toxicity is fully manifest. This concept also explains the
	discrepancy between plasma concentrations of methyl alcohol and
	clinical signs of toxicity. Furthermore, methyl alcohol poisoning
	is ameliorated by ethanol, a substance with greater affiniy than
	methyl alcohol for alcohol dehydrogenase, which is responsible for
	the initial step in metabolism.  The metabolite formate appears to
	be the mediator of ocular injury and acidosis. The individual
	variations in activity of the alcohol dehydrogenase systems, which
	are responsible for the oxidative metabolism of methyl (and ethyl)
	alcohol, may account for the wide variation in the individual
	reponses observed with methyl alcohol poisoning.

Isopropyl alcohol
CH3CHOHCH3

Synonyms:
	Isopropanol; propanol-2; dimethyl carbinol

Uses:
	Manufacture of acetone; solvent; in skin lotions, cosmetics, and
	pharmaceuticals

Exposure:
	Inhalation; ingestion

Toxicology:
	Isopropyl alcohol is an irritant of the eyes and mucous membranes;
	at high doses, it causes central nervous system depression.
	Human subjects exposed to 400 ppm for 3 to 5 minutes experienced
	mild irritation of the eyes, nose, and throat; at 800 ppm, the
	irritation was not severe, but the majority of subjects considered
	the atmosphere uncomfortable. Inhalation of high levels of
	isopropyl alcohol has occurred in poorly ventilated areas during
	sponge baths intended to reduce fever. In several cases, symptoms
	included repiratory distress, severe stupor, and coma. Recovery was
	complete in 36 hours.
	Occupational poisoning by isopropyl alcohol has not been reported.
	Toxicity in humans is based largely on accidental ingestion. An
	oral dose of 25 ml in 100 ml of water produced hypotension, facial
	flushing, bradycardia, and dizziness. Other symptoms following
	ingestion have included vomiting, depression, headache, coma, and
	shock. Renal insufficiency, including anuria followed by oliguria,
	nitrogen retention, and edema, may be a complication of isopropyl
	alcohol poisoning. Estimates of fatal doses are between 160 and 240
	ml. Death following ingestion often occurs in 24 to 36 hours from
	respiratory paralysis.

Ethyl Alcohol
C2H5OH

Synonyms:
	Ethanol; algrain; anhydol; ethyl hydrate; ethyl hydroxide; grain
	alcohol

Uses:
	Solvent

Exposure:
	Inhalation; ingestion

Toxicology:
	Ethyl alcohol is an irritant of the eyes and mucous membranes and
	causes central nervous system depression.
	Exposure of humans a 5000 to 10000 ppm has caused transient
	irritation of the eyes and nose, and cough.
	At 15000 ppm, effects included continuous lacrimation and cough. A
	level of 20000 ppm was judged as just tolerable; above this level,
	the atmosphere was described as intolerable and suffocating on even
	brief exposure.
	Chronic exposure to the vapor may result in irritaion of mucous
	membranes, headache, and symptoms of central nervous system
	depression such as lack of concentration and somnolence. However,
	in current industrial practice, the vapor is considered to be
	practically devoid of systemic hazard from inhalation.
	Ethanol is not appreciably irritating to skin, even with repeated
	or prolonged exposure.
	Splashed in the eye, the liquid causes immediate burning and
	stinging sensation with reflex closure of the lids and tearing.
	Some fetotoxicity has been observed in the offspring of mice
	treated with large doses of ethanol during gestation.



Joe Kral
kral@hpljlk.hpl.hp.com
Newsgroups: rec.crafts.brewing