Thursday, July 7, 2011

Exquisite on the outside, Lethal on the inside

Ladies and gentlemen, I am in so much bliss and proud to say, we have moved on from Endocrinology! Heck, that was some kind of brain work.


TOXICOLOGY, on the other hand, is quite interesting to me. I find it strange that I tend to like researching about anything that is potentially harmful, and even lethal to man. I guess I must blame it on too much watching of horror movies. NO, I am not sadistic and definitely not planning on doing it to anyone. But yes, I am paranoid about these things. It is nice to know what to watch out for, eh? Unfortunate for us, it can come from our own backyard.

(I seriously needed a minute to say “THANK YOU, JESUS!”. I can not stress enough how much I am loving my course right now. These things that I am learning! Just needed to put that out.)

Okay, moving on...

So to give you an idea or glimpse on what you should know about Toxicology, here are some facts I researched. Again, RESEARCHED. All references will be cited at the end of this blog entry.

Toxicology is the study of howural or man-made poisons cause undesirable effects in living organisms.

What is Toxicity?
The word “toxicity” describes the degree to which a substance is poisonous or can cause injury. The toxicity depends on a variety of factors: dose, duration and route of exposure shape and structure of the chemical itself, and individual human factors.

What is Toxic? This term relates to poisonous or deadly effects on the body by inhalation (breathing), ingestion (eating), or absorption, or by direct contact with a chemical.

What is a Toxicant? A toxicant is any chemical that can injure or kill humans, animals, or plants; a poison. The term “toxicant” is used when talking about toxic substances that are produced by or are a by-product of human-made activities. For example, dioxin (2,3-7,8-tetrachlorodibenzop-dioxin {TCDD}), produced as a by-product of certain chlorinated chemicals, is a toxicant. On the other hand, arsenic, a toxic metal, may occur as a natural contaminant of groundwater or may contaminate groundwater as a by-product of industrial activities. If the second case is true, such toxic substances are referred to as toxicants, rather than toxins.

What is a Toxin? The term “toxin” usually is used when talking about toxic substances produced naturally. A toxin is any poisonous substance of microbial (bacteria or other tiny plants or animals), vegetable, or synthetic chemical origin that reacts with specific cellular components to kill cells, alter growth or development, or kill the organism.

Classification of Toxic Agents:

Toxic substances are classified into the following:
A. Heavy Metals
B. Solvents and Vapors
C. Radiation and Radioactive Materials
D. Dioxin/Furans
E. Pesticides
F. Plant Toxins
G. Animal Toxins

-- Nature provides us some of the healthiest food and items around, but also the deadliest. Nature has provided us animal and plant toxins. It may be exquisite on the outside, but lethal on the inside.
Since there are so many of them, here's a glimpse of the silent killers out there:

Let us start with PLANT TOXINS.

According to David Zinczenko, editor-in-chief of Men's Health Magazine, “EAT RIGHT RULE: If it didn't grow, walk or swim, eat it rarely”. Well if it did grow, walk or swim, don't eat it JUST yet. The mushroom, calabar bean and castor bean are perfect examples.

We all know mushroom is an ingredient to some of our most popular guilty pleasures – pizzas, pasta dishes and who can forget the creamy mushroom soup? But it can be the recipe for disaster.

Amanita phalloides
As the common name suggests, the fungus is highly toxic, and it is responsible for the majority of fatal mushroom poisonings worldwide. It causes accidental poisoning due to its similarity to edible mushrooms.

DISTRIBUTION: It is native to and widespread in Europe.

FEATURES: Smooth, yellowish-green to olive-brown cap; white gills; white stem; membranous skirt on stem; cup-like structure around the base of the stem.

TOXICITY AND EFFECT: Half a cup is able to kill a human being.
Toxin present: anatoxin and phallatoxin

Anatoxin – halts protein synthesis by inhibiting RNA polymerase II
Phallatoxin – toxic to liver cells

Liver is the primary target. Kidneys are susceptible. Liver and kidney failure are usually the cause of death.

SYMPTOMS: The symptoms are slow to show themselves and often do not appear until 10-16 hours (or even longer) after eating.

The timing given above is approximate, for much depends on the general health of the individual and how much they’ve eaten. For example, if you’ve eaten a large meal of Deathcaps the symptoms could start as early as 6 hours after the meal.

The first symptoms are stomach pains, vomiting and diarrhoea. These may continue for a day or two, after which there is typically an easing of symptoms and apparent recovery. The "recovery" period may last for 2 or 3 days. Then the terminal phase of 3-5 days starts with the re-occurrence of stomach pains, vomiting and diarrhoea - accompanied by jaundice. Without effective, early medical intervention, coma and death occur between one and two weeks after eating the mushroom. Death is caused by liver failure, often accompanied by kidney failure.

WHAT TO DO IF INGESTED: Immediately rush to a hospital. Bring a sample of the mushroom, if possible.

For further reading, visit:


It is the seed from the plant, Physostigma venenosum, which resembles any ordinary beans. It was traditionally used in trials to prove innocence. If the accused survived its poisoning, then he is innocent. Currently, it is used for the synthesis of an alkaloid, physostigmine, which is used clinically. But today, it's usage is limited due to its toxicity. It is also called the doomsday plant by the natives of West Africa.

DISTRIBUTION: Native of tropical Africa, West Africa

FEATURES: Large, herbaceous, climbing perennial, with the stem woody at the base, up to 2 inches (5 cm) in diameter; it has a habit like the scarlet runner, and attains a height of about 50 feet (15 m). The flowers, resting on axillary peduncles, are large, about an inch long, grouped in pendulous, fascicled racemes pale-pink or purplish, and beautifully veined. The seed pods, which contain two or three seeds or beans, are 6 or 7 inches (15 or 18 cm) in length; and the beans are about the size of an ordinary horse bean but much thicker, with a deep chocolate-brown color.

TOXICITY AND EFFECT: One seed can kill a human being

Contains physostigmine, which is a reversible cholinesterase inhibitor alkaloid. Death by asphyxiation.


Physostigmine has no action on the unbroken skin. When swallowed it rapidly causes a great increase in the salivary secretion, being one of the most powerful sialogogues known. It has been shown that the action is due to a direct influence on the secreting gland-cells themselves. After a few minutes the salivation is arrested owing to the constricting influence of the drug upon the blood-vessels that supply the glands. There is also felt a sense of constriction in the pharynx, due to the action of the drug on its muscular fibres. A similar stimulation of the non-striped muscle in the alimentary canal results in violent vomiting and purging, if a large dose has been taken. Physostigmine, indeed, stimulates nearly all the non-striped muscles in the body, and this action upon the muscular coats of the arteries, and especially of the arterioles, causes a great rise in blood-pressure shortly after its absorption, which is very rapid. The terminals of the vagus nerve are also stimulated, causing the heart to beat more slowly. Later in its action, the drug depresses the intra-cardiac motor ganglia, causing prolongation of diastole and finally arrest of the heart in dilatation. A large lethal dose kills by this action, but the minimum lethal dose by its combined action on the respiration and the heart. The respiration is at first accelerated by a dose of physostigmine, but is afterwards slowed and ultimately arrested. The initial hastening is due to a stimulation of the vagus terminals in the lung, as it does not occur if these nerves are previously divided. The final arrest is due to paralysis of the respiratory centre in the medulla oblongata, hastened by a quasi-asthmatic contraction of the non-striped muscular tissue in the bronchial tubes, and by a "water-logging" of the lungs due to an increase in the amount of bronchial secretion. It may here be stated that the non-striped muscular tissue of the bladder, the uterus and the spleen is also stimulated, as well as that of the iris. It is only in very large doses that the voluntary muscles are poisoned, there being induced in them a tremor which may simulate ordinary convulsions. The action is a direct one upon the muscular tissue.

WHAT TO DO IF INGESTED: Immediately rush to a hospital.

Antidote is atropine, which may often succeed; and the other measures are those usually employed to stimulate the circulation and respiration.

For further reading, visit:

Castor Beans

The seeds of the plant, Ricinus communis, which is used as an ornament in gardens and cultivated for its oil in its leaves. Also mistaken as an ordinary edible bean, mostly by children. According to the 2007 edition of the Guinness Book of World Records, this plant is the most poisonous in the world.

DISTRIBUTION: Native to tropical Africa; Indigenous to the southeastern Mediterranean Basin, Eastern Africa, and India, but is widespread throughout tropical regions

FEATURES: The "stalked leaves consist of usually eight radiating, pointed leaflets with slightly serrated edges and prominent central veins. Many varieties are green, but some are reddish brown."(Cooper and Johnson) The flowers are green and inconspicuous, but pink or red in the pigmented varieties. Many stamens are near the base and branching pistils are near the top of the flower. The soft-spined fruits containing attractively mottled seeds are distinctive features of the plant.

TOXICITY AND EFFECT: 1 mg of ricin can kill a human being
Contains the toxic proteins, ricin and Ricinus communis agglutinin which are cytotoxins and weak hemagglutinins.


The symptoms of human poisoning begin within a few hours of ingestion. The symptoms are abdominal pain, vomiting, diarrhea, sometimes bloody. Within several days there is severe dehydration, a decrease in urine, and a decrease in blood pressure. If death has not occurred in 3-5 days, the victim usually recovers.

WHAT TO DO IF INGESTED: Immediately rush to a hospital.

For further reading, visit:



These toxins can result from venomous or poisonous animal releases.

Venomous vs. Poisonous animals

Venomous animals are usually defined as those that are capable of producing a poison in a highly developed gland or group of cells, and can deliver that toxin through biting or stinging.

Poisonous animals are generally regarded as those whose tissues, either in part or in their whole, are toxic.

-- I personally hate frogs. Other than the fact that they are slimy and grotesquely looking, they ACTUALLY JUMP... in weird height levels. Imagining a frog jumping – boink-boink. (shivers down my spine). Here's an acceptable reason to beware of frogs:


It is from the poison dart frogs of the species Dendrobates and Phyllobates.

Dendrobates auratus
Batrachotoxin (BTX), a member of the batrachotoxin family of steroidal alkaloids, was first isolated from the skin of poison arrow frogs (genus Phyllobates) from the rain forests of western Colombia. By weight, batrachotoxin is one of the most potent natural toxins known because it binds to and irreversibly opens voltage-gated sodium channels; the proper function of these sodium channels is required for the transmission of electrical signals through nerve and muscle cells.

Dendrobates historionicus
Native Indians have used this venom for hundreds of years to poison blow darts. Handling one of these frogs could kill you, if the toxin were able to enter through a cut in your skin.

DISTRIBUTION: Endemic to humid, tropical environments of Central and Latin America (South America)

There are 10 species in the genus Dendrobates. They are all brightly colored: Dendrobates azureus is blue and Dendrobates  auratus, which lives in Costa Rica, is green, with regular black spots. A very small species isDendrobatespumilio–in fact it reaches only 1.8 cm in length and is the smallest member of the family. Its back is brightly orange to red and has tiny darker spots; the limbs are black.
There are several species with very strong poison in the genus Phyllobates.Phyllobates terribilis, which is the most toxic frog from all arrow-frogs, belongs to this genus.

Dendrobates azureus

Around 136 μg is the lethal dose for a person weighing 150 pounds; that is, about two grains of table salt.

The batrachotoxin increases the permeability of the outer membrane of nerve and muscle cells to sodium ions. Thus it stops these channels within muscle fibres from closing normally, allowing a big inflow of sodium ions into the cell. This causes an irreversible electrical depolarisation, blocking the nerve signals that would normally cause the muscle to relax, the muscle remaining contracted. Certain cells within the heart are very sensitive to this, resulting in heart arrythmias, fibrillation and ultimately cardiac failure.

No effective antidotes are known. Frogs do not produce the toxin, but bioaccumulate it – captive frogs are not toxic.

SYMPTOMS: Instant paralysis, numbness, salivation, convulsions, strong muscle contractions

WHAT TO DO IF INGESTED/ INFECTED: No antidote known. Rush to the hospital immediately.

For further reading, visit:



Tetrodotoxin is a potent marine neurotoxin, named after the order of fish from which it is most commonly associated, the Tetraodontiformes (tetras-four and odontos-tooth), or the tetraodon pufferfish. Poisonings usually occur after eating fish caught and prepared by uncertified handlers.

The flesh of the puffer fish (ie, fugu) is considered a delicacy in Japan. It is prepared by chefs specially trained and certified by the government to prepare the flesh free of the toxic liver, gonads, and skin. Despite these precautions, many cases of tetrodotoxin poisoning are reported each year in patients ingesting fugu.

It can also be found on the skin and viscera of porcupine fish, globefish, balloon fish, blowfish, sunfish, toadfish, blue-ringed octopus, and some species of salamanders
Puffer fish

Puffer fish:  The tetraodon puffers are equipped with four large teeth which are nearly fused, forming a beak-like structure used for cracking mollusks and other invertebrates, as well as for scraping corals and general reef grazing.  


1.2 mg of pure toxin is lethal. 10 times more poisonous than potassium cyanide.

Contains the neurotoxin, Tetrodotoxin, which is a heat-stable and water-soluble nonprotein.

It is a heterocyclic, small, organic molecule that acts directly on the electrically active sodium channel in nerve tissue

Tetrodotoxin blocks diffusion of sodium through the sodium channel, thus preventing depolarization and propagation of action potentials in nerve cells.

All of the observed toxicity is secondary to blockade of the action potential. Tetrodotoxin acts on the central and the peripheral nervous systems (ie, autonomic, motor, sensory nerves).

Tetrodotoxin also stimulates the chemoreceptor trigger zone in the medulla oblongata and depresses the respiratory and vasomotor centers in that area.


The first symptom of intoxication is a slight numbness of the lips and tongue, appearing between 20 minutes to three hours after eating poisonous pufferfish. The next symptom is increasing paraesthesia in the face and extremities, which may be followed by sensations of lightness or floating. Headache, epigastric pain, nausea, diarrhea, and/or vomiting may occur. Occasionally, some reeling or difficulty in walking may occur. The second stage of the intoxication is increasing paralysis. Many victims are unable to move; even sitting may be difficult. There is increasing respiratory distress. Speech is affected, and the victim usually exhibits dyspnea, cyanosis, and hypotension. Paralysis increases and convulsions, mental impairment, and cardiac arrhythmia may occur. The victim, although completely paralyzed, may be conscious and in some cases completely lucid until shortly before death. Death usually occurs within 4 to 6 hours, with a known range of about 20 minutes to 8 hours.

WHAT TO DO IF INGESTED: No antidote known. Rush to the hospital immediately.

For further reading, visit:



Naturally found in black widow spiders. The most famous is the Latrodectus mactans. Their bites, however, are rarely fatal to humans.

DISTRIBUTION: Within the United States, deserts of the American Southwest, Canada, Mexico, West Indies, and South America. A terrestrial environment is the habitat of the Latrodectus mactans. It is ubiquitous and builds strong-walled retreats quite close to the ground and in dark sheltered spots. However, it also spreads its snares over plants. Webs of the black widow spider can be found in recesses under stones or logs in a woodpile, in crevices or holes in dirt embankments, in barns and outbuildings. When it does seek shelter in a building, it is due to cold weather and a need for a dry shelter.

FEATURES: The adult female Latrodectus mactans is 2-3 cm long and has a body length of 2-3 cm. The male is about four times smaller than the female and is less dangerous. Besides the reddish hourglass-shaped design, it often has four pairs of reddish stripes on the sides of the abdomen.

Causes massive release of neurotransmitters, severely impairing the victim's cardiovascular and neuromuscular systems.

Clinically, a bite of Lactrodectus rarely can cause serious health problems. In severe cases, a bite can cause lactrodectism, a disease consisting of raised blood pressure, generalized muscle pain, abdominal cramps, extreme sweating and tachycaia. The average duration of the syndrome in humans is 3 to 6 days. Untreated patients have exhibited clinical signs for a period of 7 days, but weakness and some muscle pain and malaise may persist for weeks. About 75% of the intoxicated patients experience local effects and do not develop systemic envenomation. A pinprick or burning sensation can be felt when bitten by widow spiders. Local pain worsens over time, which may combine with sweating and piloerection. The pain may spread to local lymph nodes or become generalized

There is a specific red-back antivenin which is used when signs of systemic envenomation are observed. The pressure-immobilization method is not recommended since it can cause extreme pain in the affected area. Instead, ice packs could be used for relief. Rush to the hospital if symptoms worsen.

For further reading, visit:

If you think what doesn't kill you only makes you stronger, think again.



For each toxin (in order as they were presented)

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