Sunday, July 15, 2012

Toxi-COOL-ogy: The Awesome Power of Poison and the Not so Awesome Effects

First things first:  The FUN-damentals…

Obviously, the meaning of toxicology is the study of poisons. The etymology is quite deep rooted because it came from the Latin word “toxicus” which means poisonous and that Latin word was derived from the Greek word “toxikón”, a poison where arrowheads are dipped and used as an extra lethal weapon. Talk about Toxiception.

It’s a broad study wherein everything about toxic substances, from its composition and nature to the means by which these substances cause ill effects to not only humans but also other living organisms and its consequential effect on biologic systems, are meticulously studied in full detail.

It clarifies our orthodox understanding that poisons are substances that cause immediate harm or fatality when ingested but in fact not all toxic substances causes immediate effects in our body, sometimes it needs time before it manifests itself as being harmful. That’s why toxicology goes beyond mere basic concepts of toxicity because it also assesses the quantitative relationship between the ill effects to the concentration or dosage of the substances, duration and frequency of exposure of the organisms.

Toxicology’s wide ranging character brought about the rise of different branches and sub disciplines that would tackle each parameter of toxicology in a comprehensive manner though there may be interdisciplinary relations within each of the branches.

Definition and Application
Descriptive Toxicology
Focuses on toxicity testing of chemicals or agents of toxicity, usually on animals and then correlated to human conditions. It provides dose-response information upon exposure to a harmful toxic agent.
Mechanistic Toxicology
Focuses on the in depth study of how the agent initiates its biochemical or physiologic effect on the organism whether it would be genotoxic, teratogenic, mutagenic or carcinogenic. Works as toxicokinetics and toxicodynamics.
Regulatory Toxicology
Focuses on risk assessment and exposure guideline development from gathered information obtained from toxicity testing. Establishes standards for safe exposure in occupational health guideline or governmental regulations to limit the use.
Forensic Toxicology
Focuses on the medical and legal implications of drugs, as in the cases of illegal drug use/abuse, overdose and testing, and poisons, as in the case of murders and homicides that is of importance to police and medical examiners.
Clinical Toxicology
Focuses on pathophysiology of toxicity in both chronic or acute exposure and treatment to ameliorate signs and symptoms exhibited by the toxic agent. This is also in conjunction with use of pharmaceutical drugs.
Environmental Toxicology
Focuses on the exposure of the chemical varieties of toxicants found in the general living environment and its implications on organisms, mostly on the nonhuman population.
Specialized area of environmental toxicology focusing mainly on the impacts of toxic agents in the population and its dynamics within an ecosystem and its fate.

Poison Arrow Dart

Its Dark past…..
The use of the concepts of toxicology started during the primitive times. 

One instance was the use of Curare, which is a black, resin-like toxic substance obtained from Strychos toxifera, that’s placed on arrow dart tips and were used to produce a more lethal and effective weaponry. 

To know more about how curare is made, open this link: Curare

King Mithridates VI of Pontus
During the Roman Empire, political assassinations by poisoning were rampant. The paranoid King Mithridates VI of Pontus (120-63 BCE) consumed daily small amounts of poisons, consisting of 36 different ingredients, serially increasing to gain polyvalent tolerance or immunity from different low grade poisons given by attempting poisoners. It was effective enough that he didn’t die of his own attempt of suicide by poison and had to use his sword to do the job. It led to the foundation of Mithridatium which is a concoction containing a collection of materials to prevent poisoning.

It led to the formation of the first law against poisoning, Lex Cornelia, circa 82 B.C.


To know more about Lex Cornelia, click this link: Lex Cornelia

Catherine de Medici

In the middle ages, clinical trials of toxic concoctions were used on the sick, the poor and on orphans by Catherine de Medici, Marchioness do Brinvillers and Catherine Deshayes carefully noting onset of action, potency, specificity and site of action and clinical signs and symptoms.

During the Renaissance, Philippus Aureolus Theophrastus Bombastus von Hohenheim more famously known as Paracelsus (1493–1541), the father of toxicology, created the famous maxim, “All substances are poisons, there is none which is not a poison. The right dose differentiates a poison from a remedy.” This is said to be more related to pharmacology wherein the medicinal property of the drug could be dictated by the dose, as it goes beyond the desirable dose, it becomes toxic.

Evolution of toxicology honed and polished our know-abouts on the use of chemicals, drugs and other agents that may pose diminishing effects on our health.  

Fast Fact: Edible Poison

Delectable FUGU
The Fugu is a traditional Japanese cuisine made of the fresh meat of a Puffer fish which is known to have a potent poison, tetraodontidae. It is made by slicing raw meat of the puffer fish and served with condiments. Its prepared by only licensed chefs with adequate skill to remove the toxic sac. A wrong way of preparing the dish could lead to paralysis, respiratory arrest or death.

For more information about tetrodotoxin toxicity, refer to this link.tetrodotoxin


  • History of toxicology. Published: August 24, 2008, 3:59 pm. Updated: August 24, 2008, 3:59 pm. Lead Author: Emily Monosson.
  • Principles of Toxicology. History of Toxicology. Michael J. Hooper. The Environmental Toxicology Department. Texas Tech University. Lubbock, Texas.
  •   Lu’s Basic Toxicology: Fundamentals, Target Organs, and Risk Assessment. 5th ed. Frank C. Lu. 2009. Informa Healthcare USA, Inc.
  • Principles of toxicology: Environmental and Industrial Applications. 2nd ed. 2000. Phillip L. Williams. John Wiley & Sons, Inc.
  • Principles and Practice of Toxicology in Public Health. Ira S. Richards. 2008. Jones and Bartlett Publishers.
  • Clinical Chemistry: Techniques, Principles, Correlations. 6th ed. Michael L. Bishop. 2010. Lippincott Williams & Wilkins.
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Wednesday, May 16, 2012

Oh.. Endocrinology.. Right....

Fun tidbit:
The Bearded Lady
The bearded lady you see from the circus that you are astounded of is actually an individual with a condition call hirsutism where excessive growth of facial and body hair is induced by excess androgen production and yes, like Salma Hayek in the movie ‘Cirque du Freak: The Vampire's Assistant’ where she portrays the role of the bearded lady. But no, in the real hormonal condition, the growth of hair cannot be controlled or induced according to ones will, that’s Salmas’ power.

Personal thought…

Puberty, warfare of Hormones
When I was a wee lass, I would encounter cues from old American cliché 40’s sitcoms and educational commercials or infomercials from telly(TV), where the speaker wound sound really enthusiastic plus the audio record of people laughing would make it sound more interesting to listen to that would go on something like this, “Hey Jimmy, are you experiencing changes in your body since you turned thirteen? If yes, don’t be stressed because these are normal events happening during puberty and chiefly because of HORMONES.” That’s where I first encountered one of the major concerns of endocrinology, and no, it’s not about Jimmy going through “The Phase” as they say but it’s what’s causing the phase, Hormones. Well, endocrinology isn’t all about hormones entirely though, it also involves the squishy part of our body that produces them, the tissue which is appropriately termed as glands composed of hormone secreting cells. Its collective term is the endocrine system. 

What ever is Endocrinology?

Let’s dissect the word itself, “Endo” which means within, “crino” meaning to secrete, and “logo” meaning to study.
In a comprehensive way to express what it means, it is the science which deals with the understanding of the structure of tissues composed of hormone secreting cells, wherein these tissues do not require the aid of ducts to secrete their byproducts we know as the hormones. It also tackles the comprehension of the role these structures maintaining homeostasis or the feedback system which sets the body at constant equilibrium. Being said, the aforementioned basic definition can be linked to its clinical function encompassing pathophysiology to aid in diagnosing pathologic conditions which the endocrine system is very much involved and being able to determine the disease, appropriate treatment can be formulated and provided.

Squishy Squashies

In some sources, endocrinology can also be defined as the study of intercellular communication as stated in a book by J. Larry Jameson. In the mechanism of how the endocrine system works, an endocrine cell produces hormones that is directed to a target cell, either distant or nearby. If the target cell is distant, it is secreted to the blood stream but if the target cell is nearby, the hormones travel via the interstitial space. It can also be an intracellular phenomenon where the endocrine cell producing the hormone is also the target cell; therefore it produces regulators of itself, an autocrine type of hormone transport.


The principles of Endocrinology doesn’t merely focus on one system (Endocrine System), it encompasses other body systems. In such case, the Nervous System is interlocked with the Endocrine System since the former can control the stimulation or inhibition of the function of the latter. The Endocrine System can regulate almost all cells in the body, remembering its hemostatic ability, so its effect in the body can be local or systematic.

Endocrinology is an ancient science and cause of that its boundary between other disciplines is growing thin because of its dynamic correlation with the other body systems. Its evolution continues to expand, formulate new expertise and sub-branches.

Why learn about it?
Its significance is obviously clinical, as stated earlier part of the function of endocrinology is to provide health assessment for diagnosis hormone-induced pathologies.
Diseases induced by hormonal abnormalities can be mild or severely fatal. From the slightest, reason why you don’t stop peeing because you either gulp loads of fluids or you have problems with your ADH(Antidiuretic Hormone) secretion to contracting insulin dependent diabetes.

• Clinical Chemistry: Techniques, Principles, Correlations. M. Bishop et. al. 6th Ed. 2010. Wolter's Kluwer-Lippincott Williams & Wilkins. 351 West Camden St. Baltimore.
• Harrison's Endocrinology. J. L. Jameson. 2nd Ed. 2010. Mc-Grawhill Companies Inc. China
•Endocrinology: Adult & Pediatric Vol. 1. J. L. Jameson et. al. 6th Ed. 2010. Saunders Elsevier. 1600 John F. Kennedy Blvd. Philadelphia.
• Principles of Anatomy & Physiology: Organization, Support and Movement, and Control Systems of the Human Body. Vol. 1. G. Tortora et. al. 12th Ed. 2009. John Wiley & Sons Inc. Asia-ISV

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