Ferrari L.A., Nieto R.R., Arado M.G., Wamba Z.
Laboratory of Toxicology and Legal Chemistry, Buenos Aires Court of Justice. 41 y 119 (1900) La Plata, Argentina

In blood and tissue samples, methanol was isolated by means of the Head Space method and identification and quantification by GC/FID in an isothermal state was performed.

Formic acid was determined by means of a similar technique, previously transformed into methyl formate.

Methanol and formic acid were found in high concentrations in blood and brain and to a lesser extent in liver, kidney and lung in those victims who died immediately after wine ingestion. In victims who had received treatment and did not die immediately after wine ingestion, blood, liver, lung, brain and kidney methanol concentrations decayed in a time-dependent manner to non detectable values for 10 days after ingestion. Surprisingly, formic acid remained in substantial amounts in brain for 10 days after wine ingestion.

It appears that single methanol analysis is not sufficient to make a diagnostic determination of fatal intoxication. This is especially valid for those cases in which treatment was provided. Our results show that it is necessary to assay formic acid together with methanol to prove if methanol intoxication occurred, in both lethal and non lethal cases. In our experience brain tissue was the best organ to measure formic acid in fatal cases of methanol intoxication after prolonged treatment.