OVER the past five months at least 300 children around the world have died after taking cough syrup.
In response, the World Health Organization (WHO) issued a product alert for 14 different children's medicines in Africa, south-east Asia and Europe.
The cough medicines were contaminated with toxic chemicals - ethylene glycol and diethylene glycol - which are used in windscreen wiper fluids and engine coolants.
Writing in the Conversation, Professor Winston Morgan, a toxicologist from the University of East London, explained why these chemicals are so dangerous to humans and how they ended up in cough syrups.
"These compounds are sometimes also found at very low levels as contaminants in many food ingredients and medical solvents," the expert said.
Ronaldo claims ‘multiple’ clubs in Europe tried to sign him before Al-Nassr move
"This happens when there are poor standards of manufacturing and testing," he added.
A fatal dose of the chemicals in adults is considered to be about 1,000-1,500 milligrams per kilogram.
And for a small child the deadly measure falls to 28 millilitres or about 6 teaspoons.
"It is also possible to cause toxicity by consuming much lower doses over several days and weeks," Prof Winston said.
What makes these chemicals potentially so dangerous is that a child has to consume a large amount before symptoms of contamination appear, the expert explained.
And to make matters worse, symptoms of ethylene glycol and diethylene glycol poisoning, such as drowsiness, can be misinterpreted as normal in a child with a cough or fever.
"Guardians and medical professionals may not notice what’s wrong until it’s too late," the Prof said.
Why are the chemicals so poisonous in medicines?
Ethylene glycol and diethylene glycol can mix with a naturally occurring enzyme, found in the human body, which converts the chemicals into a more dangerous compound, known as glyoxylic acid.
"Glyoxylic acid can concentrate in and damage the kidneys – leading to death from renal failure," the expert explained.
Normally, the body can regulate the chemical reactions in the body, which means the chemicals would never get converted into glyoxylic acid.
All the new travel rules you need to know for 2023 to avoid ruining your holiday
But paracetamol - which is found in cough syrups - can inhibit the body's ability to control chemical reactions, making the development of glyoxylic acid more likely.
"Children taking paracetamol preparations contaminated with the glycols could potentially be in danger," the Professor wrote.
"Other medicines and foods contaminated with low levels of ethylene glycol and diethylene glycol probably go unnoticed because they don’t contain paracetamol," he added.
Prof Winston urged parents to continue using cough medicines - but err on the side of caution.
"Medications containing paracetamol are normally very safe for children.
"But to avoid deaths related to cough syrup in future, both parents and medical professionals should consider glycol poisoning as a possibility if children start to display symptoms of intoxication and drowsiness after taking the medicine," he explained.
