Methanol Toxicity

Ups advises about methanol toxicity :
    The fatal dose of methanol is 60 to 250 mL. Death depends on the size of the individual, their general health and stomach contents. The exposure limit is 200ppm. The highly lethal nature of methanol (compared to ethanol) has not been fully researched, but it is believed to be the result of the byproducts of metabolism, which turn methanol into formic acid and formaldehyde, and formaldehyde has been proven to have selective injurious effects on retal cells- this is the reason for it's ability to cause blindness.

    Methanol is metabolized and excreted at a rate about one-fifth that of ethanol, and a single dose may take up to 4 days to leave the body (provided the drinker isn't already dead)

    Symptoms fom acute poisoning of a moderate dose- Severe headache, dizziness, nausea and vomiting, and central nervous system depression. Vision may fail temporarily or permanently after 2-6 days. In higher doses the above occurs much faster and turn into rapid shallow breathing, blood pressure falling, dilation of pupils blurring of vision, cyanosis. More than 25% of those who reach this level, even in a hospital, still die.

    Chronic poisoning tends to result in visual imparement as the first symptom. The only treatment from chronic poisoning is to halt all exposure.

    Treating acute cases must be done within 2 hours of ingestion: give syrup of ipacac. Lavage thoroughly with 2-4L of tap water with sodium bicarbonate (20G/L) added. This is to treat acidosis of the blood)

    Antidote: Give ethanol, 50%, 1.5ml per kilo of body weight, orally, diluted to no more than a 5% solution, followed by 0.5-1ml/kg every 2 hours orally for 4 days. ethanol interferes with the absorbtion of methanol by the body and allows it to be excreted with less damaging effects. Also give up to 4 litres of water daily to maintain adequate urine output. Control delirium by giving 10mg valium slowly by injection in order to prevent respiratory depression.

    Prognosis:in acute methanol poisoning approx 50% do not recover. Visual imparement will show no improvement after 1 week.

    Looking up medical and drug testing labs in the phonebook will help you find someplace to send a sample of the stuff your making (say you found it in a friend's room and your worried about what he's drinking) to see how clean it is.     This page last modified Tue, 20 Jan 2015 20:51:05 -0800