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The reach of modern toxicology is extraordinarily broad. For the purposes of this website, we’ve carved out facets of the field that is better served under different headings.

• Military The effects of exposure to chemical WMDs–e.g., vesicant and asphyxiating gases; nerve agents–e.g., sarin, tabun, and extermination gas–e.g., Zyklon B, and international accords put into place to prevent their future use are under Military medicine.

• Environment The reader will find details about the release of toxic chemicals into the air and water, either intentional–e.g., pesticides–e.g., DDT, and herbicides–e.g., 2,4-D, Agent Orange or accidental–e.g., dioxins (Times Beach), methyl mercury (Minimata Bay), and methyl isocyanate (Bhopal) under Environment. 

• Occupational health Certain types of exposure–e.g., to rock, coal and chimney dusts, lead smelting, and asphyxiant gases–e.g., helium, fall under the toxicology umbrella. However, safety protocols, OSHA, and legislation related to concentrations in the air and length of time that workers are exposed to hazardous materials make it more efficient to address work-related toxicology under occupational medicine. 

• Public health Until the dawn of the 20th century, a veritable cornucopia of toxins and poisons could be added with impunity to products by food and drug manufacturers. No laws said they couldn’t, so they did. The Pure Food and Drugs Act 1906 put the kibosh on that by forbidding poisonous preservatives and dyes in foods and products destined for human consumption. The reader will find the regulatory aspect of toxicology under Public health

• Addictive substances Whilst addictive substances are clearly toxic, their use and abuse even when in excess, are not the usual purview of toxicologists and/or poison control centers, unless little Johnny got into mum’s or dad’s liquor locker, holiday ‘stash,’ or vaping paraphernalia, and decided to scarf down the contents of one or more of one of his parents’ “special places.” With that noted exception, toxicology related to pleasure poisons will be found under Alcohol, Tobacco or Substance abuse. 

The Society of Toxicology defines the field as…the study of the adverse effects of chemical, physical, or biological agents on living organisms and the ecosystem, including the prevention and amelioration of such adverse effects. A poison is a solid, liquid or gas which, if introduced in a living organism can cause ill health or death. 

toxicology socrates image from New Medical Terms


Poisons and their use to dispatch those deemed undesirable by the muckamucks du jour have been around at least since the dawn of Western civilization. 

On the one hand, are the poisoned:

•In 399 BC, Socrates (image, right), the classical Greek philosopher, was sentenced to death for corrupting the minds of the youth of Athens, and ended his life with a hemlock cocktail containing the lethal alkaloid coniine. 

•In 30 BC, Cleopatra allegedly committed suicide with an asp*. 

*An Egyptian cobra, when Mark Antony, her lover and father of three of her children lost the Battle of Actium to forces commanded by Caesar’s rightful heir, Gaius Julius Caesar Octavianus

•In 1944, the highly respected (by both the Allies and the Axis) German Field Marshal Erwin Rommel who’d been implicated in the plot to assassinate Hitler*, committed suicide with cyanide.

*Cyanide was also used for self-dispatch by Adolf Hitler, Eva Braun, the entire Goebbels family, Heinrich Himmler, Odilo Globocnik, and Hermann Göring, all of whom were Nazis and died between 1945 and 1946. 

On the other hand were the poisoners: 

toxicology Borgias image from New Medical Terms

Toxicology – the Borgias

This rogues’ gallery includes Mitridates VI of Pontus (135–63 BC), Lucrezia Borgia (1480-1519)–femme fatale of the Italian Renaissance, her brother Cesare Borgia–considered a major inspiration for Niccolo Machiavelli’s, The Prince (above image) Venice’s Council of Ten (1310-1797), Catherine de’Medici (1519-1589) and others. In years past, arsenic, also ghoulishly known as inheritance powder, was the most commonly used poison, given that it was largely undetectable by the methods of the day. 

That changed with the lurid 1840 trial of Marie Lafarge (1816-1852), a French pretender to moneyed high society who was accused of poisoning her husband with, you guessed it, arsenic. The Lafarge trial was notable for two reasons: it was closely followed by the public due to daily newspaper coverage and it was the first time forensic toxicology evidence, specifically the Marsh test, was used to convict a defendant. After a Hollywood-worthy courtroom drama, Marie Lafarge was found guilty and sentenced to life imprisonment, of which she served 12 years. For his role in providing the science behind the conviction, French toxicologist Mathieu Orfila (1787-1853) has been called the father of modern toxicology. 

Orfila’s Traite des Poisons (1813) was followed by Robert Christison’s Treatise on Poisons (1829), Theodore Wormley’s Microchemistry of Poisons(1869) and Casarett and Doull’s Toxicology: The Basic Science of Poisons (first published in 1975, now in its 7th edition), the ‘bible’ of toxicology.

In dealing with poisons, the managing clinician will assess route of exposure–cutaneous, respiratory tract, and gastrointestinal and stop further accumulation of the toxin, by cleaning the skin, removing the individual from the environment if the poison is airborne or, if appropriate, using activated charcoal in the stomach to minimize further gastric absorption. Because each poison has a relatively unique ADME (absorption, distribution, metabolism and excretion) profile, a ‘one size fits all’ management strategy won’t always work. When in doubt, call the poison control center. 

DR Badar Uddin Umar, a toxicologist from Malasia delineated the desirable features of the ideal homicidal poison. It should:

•Be cheap and readily available 

•Be colorless, odorless, and tasteless 

•Be easily co-administered with food 

•Be highly toxic and guarantee death 

•Be suggestive of a natural death 

•Cause minimal postmortem changes; routine postmortem toxicology should be negative 

Examples Fluorine, thallium, less commonly, arsenic, aconite

Per Dr Uman, the ideal suicidal poison should: 

•Be cheap and readily available 

•Be tasteless or, ideally, have a nice taste

•Be capable of co-administration with food 

•Be highly toxic and guarantee death 

•Produce a painless death 

Examples Opium, barbiturates, less commonly, organophosphate pesticides and acetaminophen

No overview of toxicology, however brief’ would be complete without mentioning the toxicologists’ hero from Hell, Dr Harold Shipman (1946-2004). This Hyde, Bedfordshire, GP’s MO included changing his patients’ wills to leave him everything and overdosing the little dears (most of the victims were elderly women) with morphine. By the time he was caught in 1998, the body count for this most prolific of all British serial killer passed 250. And nobody suspected a thing…



Toxicology Ignored The UK’s Arsenic Act of 1851 (14 & 15 Vict c. 13) resulted from growing public concern over accidental and deliberate arsenic poisonings.