Ethanol For The Treatment of Methanol Poisoning Members: 李海仙 Dora 2004050198 黄丽慧 Lilis 2004053907 潘永辉 Pamk 2004050194 李深 Martin 2004050206
Background • In China, there has been many death cases of methanol poisoning reported. Almost all cases reported are caused by ingestion of fake alcohol(methanol) as a substitution of common alcohol(ethanol). Ethanol is also a highly toxic compound ; however, it has often been used as an antidote for methanol poisoning. Therefore, we conduct this experiment to verify the efficacy of ethanol in treating methanol poisoning.
Mechanism of Methanol Toxicity • Methanol is readily absorbed into the body. The metabolism of methanol is carried out in the liver by the enzyme Alcohol Dehydrogenase (ADH). It can be metabolized to highly toxic compounds (formaldehyde and formic acid) that are responsible for the acidosis and blindness characteristic of methanol poisoning and even death.
Treatment with Ethanol • Ethanol is a competitive inhibitor of ADH. It’s affinity for ADH is 10-20 times greater than that of methanol. Ethanol slows the rate of methanol’s conversion to formaldehyde and formic acid, allowing the body time to excrete methanol in the breath and urine. ADH Formic Acid Methanol Formaldehyde - - Ethanol
Experimental Procedure • Groups: 20mice divided into 5 groups • Administration route: intragastric (灌胃) • Group A is for preliminary experiment to determine the minimum lethal dose of methanol in mice. • The minimum lethal dose obtained is 0.150ml/10g .
Discussion • The results showed that the death time of the 40% Ethanol group (105min) is longer than the death time of the blank group (76min). • No death observed in the 60% Ethanol group and Folic Acid group. • The death time of the methanol-poisoned mice has been delayed. This has proven that ethanol is effective in treating methanol poisoning.
Discussion (cont’d) • From the experiment, we’ve found out that ethanol does relieve methanol poisoning. However, excess ethanol has a certain side effects to our body. From here, we can actually conduct a further study to create an ethanol-like drug with its side effects decreased but still having the competitive function with methanol. --- Great discovery.