Tag: toxin

Posted in Psychology & Medicine

Fried Rice Syndrome

Posted on by Jinavie

Food poisoning is most often caused by the bacteria Staphylococcus, which produces a toxin that stays on food even when it is properly prepared. The body senses the toxin and promptly tries to rid itself of the toxins, resulting in heavy vomiting 1-2 hours after eating the spoiled food.

Many different germs can cause food poisoning, among which one of the most interesting is Bacillus cereus. B. cereus is found on many different foods, but it is commonly associated with a type of food poisoning called fried rice syndrome. It creates spores that can survive if food is not improperly cooked (as in not hot enough or cooked for long enough), as the temperatures are not high enough.

Unlike infections such as gastroenteritis where the bacteria are killed by heat during cooking, spores are quite resistant to short periods of reheating, such as microwaving. This means that if the spores were not killed when the rice was first cooked, it stays around even after refrigeration and reheating. The bacteria grow from the spore and start producing a toxin called cereulide. One to five hours later, the person who eats this tainted rice develops severe vomiting and nausea.

Fortunately, like most food poisonings, fried rice syndrome is easily treated with supportive management. The body does most of the work by decontaminating itself through vomiting. The important part is staying hydrated by keeping up with fluid loss. Most food poisoning cases resolve on their own within 24 (miserable) hours.

Posted in Psychology & Medicine

Mithridatism

Posted on by Jinavie

Mithridates VI, the King of Pontus (ancient Greek/Persian state located in modern day Turkey), had a paranoia that there were people who wanted to assassinate him through poison. This likely stemmed from his father being poisoned by his mother (reportedly), who favoured his brother over Mithridates as the heir to the throne. He noticed in his youth that the meals brought to him induced stomach pains. He connected the dots and deduced that his mother was trying to poison him slowly so that his brother would become the next king. He fled to the wilderness and devised a plan to protect himself. It is said that he began taking a concoction of various poisons in non-lethal doses every day, to develop an immunity to the most common poisons available during his time. This led to the idea of mithridatism – the gradual self-administration of non-lethal doses of poison to develop immunity. Ironically, Mithridates’ plan backfired eventually when he attempted suicide by poison after a massive defeat against Rome. He found that the poison had no effect on him and had to request his bodyguard to kill him by sword.

Mithridatism has been recorded or suspected in various times of history. Indian epics tell the story of the king Chandragupta Maurya – the first king to unite India – who selected a group of beautiful girls and raised them in the palace. He gave the order to administer small amounts of poison to these girls as they grew up, making them invulnerable to toxins. He called these girls vishakanyas (poison maiden) and believed that they could be used as assassins who could kill men through the act of sex.
There are suggestions that Rasputin was also a practitioner of mithridatism and that this was why he survived an assassination attempt involving poison, but there is not much evidence for this.
The practice of mithridatism is also mentioned in various fictions, such as The Count of Monte Cristo and The Princess Bride.

The concept of taking small doses of something to build up an immunity is still used in modern medicine. Desensitisation therapy is used to treat certain allergies, by exposing the body to small doses of the allergen. It is well-known that alcoholics and drug addicts required more substance to achieve the same effect as most people because they develop tolerance to it. There is some evidence that mithridatism is an effective way to build immunity to venomous snake bites.
However, not all poisonings can be avoided with mithridatism. Poisons such as cyanide pass through the system too quickly to create any tolerance, while heavy metals simply build up in the body to create a toxic effect after a history of exposure.

Posted in Psychology & Medicine

Belladonna

Posted on by Jinavie

The belladonna flower has a name that means “beautiful lady” in Italian. However, its other common name has a completely different meaning – the deadly nightshade. Both names can be explained by the uses of the flower throughout history. The deadly nightshade (Atropa belladonna) is a small shrub with purple bell-shaped flowers and shiny black berries. All parts of the plant contain various toxins such as atropine, scopolamine and hyoscyamine. These alkaloid toxins are included in a group of chemicals called anticholinergics, because they act on cholinergic receptors on neurons, which are involved in activating the parasympathetic nervous system. As cholinergic receptors are widely utilised throughout the body, anticholinergic toxicity causes a wide range of symptoms.

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The main symptoms of anticholinergic toxicity are best remembered using the following mnemonic:

  • Hot as a hare (increased temperature – reduced temperature regulation)
  • Blind as a bat (blurred vision – dilated pupils)
  • Dry as a bone (dry skin, eyes and mouth – decreased secretions)
  • Red as a beet (flushing – dilation of blood vessels)
  • Mad as a hatter (hallucinations and agitation – neurological interaction)

The name deadly nightshade is obvious as severe toxicity leads to seizures, coma and death. The reason why the deadly nightshade is also called belladonna is that the diluted extract from the plant was used as an eye drop to dilate women’s pupils – a look considered beautiful then (nowadays the effect is used to examine the eye). The toxins extracted are used in other fields of medicine too. Although not used now, anticholinergics were used as an anaesthetic for surgery due to its neuropsychiatric effects. However, atropine is still used in the emergency setting to reverse bradycardia (excessively slow heart rate), as anticholinergics speed up the heart rate. This highlights the fundamental principle of medicine that “the dose makes the poison”. For the only difference between medicine and poison is the dose… and intent (Oscar G. Hernandez, MD).

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Posted in Science & Nature

Dihydrogen Monoxide

Posted on by Jinavie

Many people know about the dangers of chemicals such as lead and dioxin, but there is lack of awareness of an even bigger killed chemical: dihydrogen monoxide. It is a colourless, odourless, tasteless chemical that is responsible for the death of hundreds of thousands of people around the world.

Most deaths caused by dihydrogen monoxide (DHMO) are by accidental inhalation, causing cerebral hypoxia. However, the dangers of DHMO do not end there. Its solid form can cause severe tissue damage after prolonged exposure, and both its gas and liquid forms can cause severe burns. It is possible to overdose on DHMO, with symptoms ranging from excessive diaphoresis and micturition, bloating, nausea, vomiting and body electrolyte imbalance such as hyponatraemia. For those who are dependent on it, withdrawal means certain death. DHMO has also been found in various types of tumours biopsied from terminal cancer patients.

Not only does DHMO have consequences on human health, it is also damaging for the environment. DHMO is the leading cause of the greenhouse effect (surpassing carbon dioxide), a key component of acid rain, accelerated corrosion and rusting of many metals and contributes to the erosion of natural landscapes. DHMO contamination is a real, global issue, with DHMO being detected in lakes, streams and reservoirs across the globe. DHMO has caused trillions of dollars of property damage in almost every country, especially in developing nations.

Despite the danger, DHMO is commonly found in the household, in the form of additives in food and drinks, cleaning products and even styrofoam. There are no regulation laws for DHMO and multi-national companies continue to dump waste DHMO into rivers and the ocean. It is astounding to see such a deadly chemical go unregulated.

If you have not caught on by now, dihydrogen monoxide’s chemical formula is H2O – also known as water. Technically speaking, there are no false statements in the above description. But even children know that water is not only (relatively) safe, but necessary for life. The report on “dihydrogen monoxide” originates from a 1997 science fair project by Nathan Zohner, who was 14 years old at the time. His project was titled “How Gullible Are We?” and involved presenting his report about “the dangers of DHMO” to fifty school students to see what their reaction would be. 43 students favoured banning it, 6 were undecided and only one recognised that DHMO was actually water. Even more surprising is that there are cases (such as in California in 2004), where city officials came close to banning the substance, falling for the hoax. This goes to show how gullible people can be in the face of what they do not know.

Posted in Psychology & Medicine

Laughter Epidemic

Posted on by Jinavie

It is said that laughter is infectious. In 1962, an extreme case of “laughter infection” happened in village in Tanzania. The phenomenon originated in a boarding school for girls. On January 30, three girls spontaneously burst out in laughter and could not stop themselves from laughing. Soon after, the whole class was suffering from fits of uncontrollable laughter. The “infection” then spread throughout the school, claiming 95 of the 159 students over a stretch of two months. This strange symptom of uncontrollable laughter lasted anywhere from a few hours to 16 days. Interestingly, teachers were not affected and only girls between the ages of 12 to 18 were affected. By March 18, the school was forced to close down due to students not being able to focus during class.

The laughter epidemic was not localised to the school. After the school shut down and the girls returned home, fellow villagers were afflicted by the laughing disease, resulting in 217 villagers being “infected” by May (mostly children and teenagers). By June, the laughing epidemic spread to another nearby school, affecting 48 girls. The epidemic then went on to claim two more schools, forcing them to close down. By the time the epidemic died down (6 to 18 months after “patient zero”), it had affected over a 1000 people and shut down 14 schools.

So what was this strange disease? Was it some new viral infection causing neurological symptoms? Was it a toxin in the water supply? The answer was even simpler: mass psychogenic illness, also known as mass hysteria. Mass hysteria is a psychological phenomenon that occurs in groups placed in high-tension situations, such as within an airplane. This setting is perfect for triggering a mass delusion, causing the person to believe they are suffering from a physical disease. The trigger is usually another “patient” and the hysteria spreads like wildfire, usually by people seeing affected victims. Although the above case makes mass hysteria look like a harmless, amusing phenomenon, psychosomatism (when the mind tricks the body into thinking it is sick) can cause symptoms such rashes, fevers, vomiting and even paralysis. In fact, all of these symptoms were also reported during the Tanganyika laughter epidemic.

Posted in Psychology & Medicine

Tetanus

Posted on by Jinavie

Tetanus is an infectious disease caused by a soil-borne bacteria called Clostridium tetani. Patients are often infected soil entering the blood through deep wounds, such as a cut. The bacteria produces a toxin called tetanospasmin which leads to the characteristic symptoms of tetanus involving muscle.

The term tetanus actually refers to a state where skeletal muscle remains contracted and cannot relax due to maximum signalling from the nervous system. Tetanus is associated with some distinct symptoms involving tetanised muscles.

Tetanus starts in the face in the form of lockjaw (jaw clamps shut and cannot be opened) and sardonic risus sardonicus. Risus sardonicus, also known as sardonic grin, is a contorted, malicious-looking smile that is caused by spasms of muscles in the face. A good portrayal of the grin is seen in the Joker’s face from the Batman comic book series.
The disease then progresses to cause stiff neck, spasming of chest and leg muscles and difficulty swallowing. 

A dramatic symptom is opisthotonos, where the patient experiences extremely painful contractions of back muscles causing them to arch their back against their will. Along with lockjaw and risus sardonicus, it is a characteristic sign of tetanus and has been known for centuries. Before it was attributed to tetanus, people used to think the person was possessed by a demon due to the agonised screams and involuntary spasming of the body.

The disease is especially devastating in infants and can be spread to the fetus within the womb. This is because babies do not have a developed passive immune system that can combat the infection. Neonatal tetanus carries a mortality rate of over 90% and is responsible for 15% of all neonatal deaths.

Tetanus is a preventable disease through immunisation. Immunisation is done by injecting an inactive form of the toxin (i.e. cannot cause disease), inducing a reaction by the immune system. This essentially “teaches” the immune system to defend the body against tetanus. By completing a course of three doses and receiving occasional booster shots throughout life, tetanus can be prevented. Pregnant women must be immunised against tetanus to prevent neonatal tetanus (the babies receive scheduled immunisations soon after birth too).

This is one example of how immunisation can effectively prevent fatal diseases in a population.