Recent reports in both the print and electronic media have highlighted the deaths caused by unscrupulous people lacing alcohol with methanol with over 20 people confirmed dead in various parts of central Uganda. The major culprit is alcohol packed in sachets and sold at low prices. This is not the first time deaths due to methanol poisoning are occurring in Uganda, as such incidences have happened in the not so far past. It's important that people try to understand what methanol is, its dangers and what should be done to minimise human deaths in the alcohol drinking population.

Cases in other countries:

In September 2006 a total of 788 cases were reported in Nicaragua. Over 40 people died and more than 160 were hospitalised due to methanol poisoning. In 2009, over 130 people died in Gujarat, India as a result of methanol poisoning.

What is this substance?

Methanol, although less intoxicating than alcohol, is far more dangerous, and deaths from this cause are not thought to be wholly accidental.

Methanol, also known as methyl alcohol, carbinol, wood alcohol, wood naphtha or wood spirits, is a highly toxic alcohol (chemical). Drinking 10ml (two teaspoonfuls) will cause blindness, and as little as 100 ml will cause death.

It is the simplest alcohol and is a light, volatile, colourless, flammable, liquid with a distinctive odour that is very similar to but slightly sweeter than ethanol (drinking alcohol). Because of its toxic properties, methanol is frequently used as a denaturant additive for ethanol, manufactured for industrial uses. Methanol is often called wood alcohol because it was once produced chiefly as a by-product of the destructive distillation of wood.

Applications:

Methanol is a common laboratory solvent. The largest use of methanol by far is in making other chemicals. About 40 per cent of methanol is used in the manufacture of plastics, plywood, paints, explosives and permanent press textiles.

Methanol is a traditional denaturant for ethanol, thus giving the term methylated spirit. Ethanol is sometimes denatured (adulterated), and thus made undrinkable, by the addition of methanol. The result is known as methylated spirit. Methanol is also used as a solvent, and as an anti-freeze in pipelines and windshield washer fluid. It is also used in wastewater treatment plants.

The chemical is also a widely used fuel in camping and boating stoves. It burns well in an unpressurised burner, so alcohol stoves are often very simple, sometimes needing little more than a cup to hold fuel. This lack of complexity makes them a favourite of hikers who spend extended time in the wilderness.

Health and Safety:

Toxicity:

Methanol is toxic. If ingested, as little as 10ml can cause permanent blindness by destruction of the optic nerve. The usual fatal dose is 100-125 ml. Toxic effects take hours to start and effective antidotes can often prevent permanent damage.

Because of its similarities to ethanol (the alcohol in beverages), it is difficult to differentiate between the two (such is the case with denatured alcohol).

Methanol is toxic by two mechanisms. Firstly, methanol (whether it enters the body by ingestion, inhalation or absorption through the skin) can be fatal due to its Central Nervous System depressant properties in the same manner as ethanol poisoning.

Secondly, in a process of toxication, it is broken down to acids through actions in the liver. The acids are toxic as they inhibit enzymatic action leading to hypoxia (oxygen deficiency) at cellular level. Feotal tissue will not tolerate methanol. Management of methanol poisoning thus involves preventing breakdown of methanol to toxic metabolites so that it excreted by the kidneys.

The initial symptoms of methanol intoxication are those of central nervous system depression: headache, dizziness, nausea, lack of coordination, confusion, drowsiness, and with sufficiently large doses, unconsciousness and death. The initial symptoms of methanol exposure are usually less severe than the symptoms resulting from the ingestion of a similar quantity of ethanol.

Once the initial symptoms have passed, a second set of symptoms arises, 10 to as many as 30 hours after the initial exposure to methanol, including blurring or complete loss of vision and acidosis (abnormally high acidity of the blood and other body tissues). The initial symptoms resemble ethanol intoxication and consist of drowsiness, confusion as well as weakness, headache, nausea, vomiting, and abdominal pain. Collectively, these symptoms may mimic an alcohol hangover, and are due to mild intoxication by the methanol itself. These symptoms result from the accumulation of toxic levels of breakdown products of methanol in the bloodstream, and may progress to death by respiratory failure.

What should be done?

The regulatory authorities should be more vigilant in assessing brewers and packers of alcohol to ensure that the products are certified before being made available for consumption by the public.

Local authorities and consumer protection agencies should sensitise people about the dangers of adulterated alcohol so that people are made aware of the repercussions. Consumers should be educated on safe consumption and discouraged from drinking alcohol from unknown sources. Regular publicity campaigns should be conducted to ensure this problem is seriously mitigated. Suffice to note that most people have been associating these so called 'mysterious deaths' to witchcraft. As noted above, the major symptoms occur 10-30 hours after initial exposure, and thus many people may not easily associate the effects to the ingestion of adulterated alcohol and will thus look for other reasons to explain the malady.

The writer is a Pharmacist, and president of the Pharmaceutical Society of Uganda