Last month, when six Vietnamese people were found dead at a luxury hotel in Bangkok, the news spread internationally. An autopsy conducted by Chulalongkorn Hospital reported that cyanide was the cause of death for all six victims. The tragic incident brought up memories of the case of Am Cyanide in 2023 and renewed awareness of the dangers of cyanide.
Am is currently charged with the murder of 14 people by using cyanide and attempted murder of one victim who survived. To raise awareness and discuss cyanide, Kasetsart University organised a forum titled "How To End Danger From Cyanide Poisoning". At the start of forum, Assoc Prof Sasimanas Unajak, the director of the Innovative Vaccine and Veterinary Biologics Center at Kasetsart University, gave examples of two cases in Thailand which made people realise the danger of cyanide poisoning is closer to everyone than people think.
"This year, a five-year-old child was hospitalised after inadvertently consuming a sip of cleaning solution which contained cyanide as one of its ingredients. After collaboration between Khun Yuam Hospital and Sri Sangwan Hospital in Mae Hong Son and receiving antidotes, sodium nitrite and sodium thiosulfate, the child recovered," said Assoc Prof Sasimanas. "A case in 1999 involved siblings from Chachoengsao.
Nine hours after a four-year-old girl and her one-and-a-half-year-old brother consumed boiled cassava, they began vomiting violently and lost consciousness. They were sent to Ramathibodi Hospital and were reported to have low blood pressure. Their breath had the smell of burned peanuts.
Cyanide levels in their blood were 0.56 and 0.32 μg per ml, respectively.
After they received antidotes similar to the case in Mae Hong Son, they recovered." Assoc Prof Sasimanas explained that cyanide can come from two sources: natural and synthetic. Synthetic cyanide, often in the form of a salt like potassium cyanide, can be easily added to food and drinks, and leads to immediate death.
"Potassium cyanide is commonly used in industrial settings. Natural cyanide exits in various forms. For instance, it is found in a natural compound present in seeds of apples, apricots, cherries, plums and peaches.
Cassava, beans and bamboo shoots also contain another type of cyanide," said Assoc Prof Sasimanas. After becoming aware of the foods that contain natural cyanide, people may wonder what is the safety margin for consumption of these kinds of food. Assoc Prof Sasimanas explained that people have to consume an unusually large quantity of the seeds for the cyanide to become toxic.
"The toxicity of cyanide is related to its taste. For example, the bitter seeds of apricots contain 0.79 to 2.
50mg of cyanide. A toxic dose is considered to be 4.48 to 14.
17g of these seeds. The sweet seeds of apricots contain 0.006 to 0.
22mg of cyanide. A toxic dose is considered to be 500 to 1,900g of these seeds." Assoc Prof Sasimanas also suggested reducing the amount of cyanide in food by boiling and discarding the water several times.
As age and weight influence vulnerability to cyanide poisoning, Assoc Prof Sasimanas recommended that children avoid consuming these foods and consumption be limited to adults. Prof Dr Upathump Supasinthu, a nephrologist at Phramongkutklao Hospital, said that the health effects of cyanide exposure depend on the amount of cyanide and how it was absorbed into the body, as well as the age and weight of the person. "Inhalation causes rapid effects, with death occurring within one to 15 minutes due to cyanide's attachment to haemoglobin and prevention of oxygen transport.
Cyanide poisoning through ingestion is influenced by stomach contents at the time and amount consumed. Consuming a small amount of cyanide can lead to death within 30 minutes to two hours. Dermal absorption symptoms can take 30 minutes to several hours to occur, with death occurring within one to several hours.
It is important to avoid touching these patients," explained Prof Dr Upathump. Prof Dr Upathump explained the symptoms that may occur after cyanide poisoning. "After cyanide exposure, these body systems will be affected followed by various symptoms: the nervous system [headache, dizziness, numbness and anxiety], respiratory system [suffocation, panting and chest pain], cardiac system [heart palpitations and low blood pressure], and integumentary system [patches of cherry red skin].
For severe symptoms, patients may be subjected to unconsciousness, seizures, respiratory arrest and cardiac arrhythmia," he said. "First aid can be effective for some types of poisoning. However, in cases of cyanide poisoning, immediate medical attention is crucial.
Inducing vomiting is not recommended as it can accelerate the absorption of the cyanide. If exposed to cyanide through skin, remove any contaminated clothing, shower thoroughly and seek medical help immediately." Assoc Prof Weerachai Phutdhawong, vice-president at the Department of Innovation and Social Mission, Kasetsart University, is a chemical specialist who examined cyanide samples provided by the Police Forensic Science Division in the case of Am Cyanide.
Assoc Prof Weerachai explained that the analysis of samples can be done by a handheld Raman spectrometer, a headspace detector or through ion chromatography. These are recognised for their effectiveness in detecting cyanide and providing accurate results. Assoc Prof Weerachai raised a critical question as to why cyanide is easy to find in Thailand.
He pointed out that it is because Thailand's regulation is outdated. "Permission is required only for those possessing 100kg or more of cyanide. However, fatal cyanide poisoning cases typically involve only a small amount of the substance.
Looking through the internet, I found that 500g of potassium cyanide can be purchased for over 2,000 baht. This quantity is sufficient to cause the death of many people," said Assoc Prof Weerachai. "Should the regulation change? People have easy access to cyanide, including cyanide that is found in products like cleaning solutions.
Cleaning solutions do not label the amount of cyanide in their products. Therefore, people are unaware of the danger and handle the product without proper precautions." In the tragic case of the Vietnamese victims, the police have not revealed whether the cyanide was obtained locally or brought from abroad.
However, Assoc Prof Weerachai believes that the crime was intended to be committed in Thailand due to the ease of acquiring this toxic substance. Therefore, he emphasises the need for strict measures to prevent the public from easily obtaining potassium cyanide. "If such strict measures were implemented, cleaning solutions would require a formula change.
It is the duty of innovators and entrepreneurs to develop effective and safer alternatives to these cleaning solutions. I hope everyone keeps a cautious mindset and uses the information from this forum positively. Do not trust people and accept food from strangers.
I hope such tragic incidents never occur again," Assoc Prof Weerachai said..
