birth defects in laboratory animals.
even the staunchest critic of formaldehyde involvement
in methanol toxicity admits:
"It is not possible to completely eliminate
formaldehyde as a toxic intermediate because formaldehyde
could be formed slowly within cells and interfere
with normal cellular function without ever obtaining
levels that are detectable in body fluid or tissues."34
Acute Toxicity in man "Toxic Syndrome"
A striking feature of methyl alcohol syndrome the
asymptomatic interval (latent period) which usually
lasts 12 to 18 hours after consumption. This is followed
by a rapid and severe acidosis caused partially by
the production of formic acid. Insufficient formic
acid is generated to account for the severity of metabolic
acidosis produced and, therefore, other organic acids
may be involved.
Patients may complain of lethargy, confusion, and
impairment of articulation, all frequently encountered
signs in moderate central nervous system (CNS) intoxications
resulting from other toxic compounds.
Patients may also suffer leg cramps, back pain,
severe headache, abdominal pain, labored breathing,
vertigo and visual loss, the latter being a very important
clue to making a diagnosis of methanol poisoning.
Other striking clinical features associated only with
the oral administration of methanol are elevated serum
amylase are the finding of pancreatitis or pancreatic
necrosis on autopsy.
In fatal cases liver, kidneys and heart may show
parenchymatous degeneration. the lungs show desquamation
of epithelium, emphysema, edema, congestion and bronchial
Chronic Human Exposure
This is the most important aspect of methanol toxicity
to those who are interested in observing the effect
of increased methanol consumption on a population.
The data presented here were compiled by the Public
Health Service. The individuals studied were working
in methanol contaminated environments. It is interesting
to note that the visual signs always associated with
acute toxicity often do not surface under chronic
Many of the signs and symptoms of intoxication due
to methanol ingestion are not specific to methyl alcohol.
For example, headaches, ear buzzing, dizziness, nausea
and unsteady gait (inebriation), gastrointestinal
disturbances, weakness, vertigo, chills, memory lapses,
numbness and shooting pains in the lower extremities