Formate is assumed to be the toxic agent. This reaction is slower as compared with the transformation of formaldehyde to formic acid, which may explain the reason for the latency of symptoms between ingestion and effect. The eye damage caused by methanol has been well described. However, the mechanism behind this phenomenon is not well understood. The major damage occurs at the retrolaminar optic nerve with intra-axonal swelling and organelle destruction.
Methanol also affects the basal ganglia.
With severe intoxication both hemorrhagic as well as non-hemorrhagic damage of the putamen is commonly seen. The predilection for and mechanism of toxicity to the putamen is not understood. Some postulate that striatal neurons have a varying sensitivity to toxic metabolites of methanol. Anterior horn cell loss has also been documented. Exact figures of morbidity and mortality from intoxication are not available.