THE HISTORY OF TOXICOLOGY

          The society of toxicology defines toxicology as “the discipline that integrates all scientific information to help preserve and protect health and the environment from the hazards presented by chemical and physical agents”.
          The hazard of a chemical or physical agents is its capacity to produce particular types of adverse effect. Hazards are usually determined using information collected from studies conducted in animals, and also from studies in which human populations have been exposed to chemicals.
         As it is stated above, the historical development of toxicology began with early cave dwellers who recognized poisonous plants and animals and used their extracts for hunting in warfare. By 1500 BC, written records indicated that hemlock, opium, arrow poisons, and certain metals were used to poison enemies or for state executions.
         Paracelsus (Theophrastus Phillipus Auroleus Bombastus Von Hohenheim 1493-1541) determined that specific chemicals were actually responsible for the toxicity of a plant or animal poison. He also developed the concept of dose. His studies revealed that small doses of substances might be harmless or beneficial whereas larger doses could be toxic. This is now known as the dose-response relationship, a major concept of toxicology.
Paracelsus is often quoted for his statement:
All things are poison and Nothing is without poison; only the dose makes a thing a poison.

This is often condensed to:

The

dose makes the poison “.

Mathieu Orfila (1787-1853) is considered to be the father of modern toxicology, having given the subject its formal treatment in 1813 in his Toxicology generate (Trait des poisons). Orfila prepared a systematic correlation between the chemical and biological properties of poisons of the time. He demonstrated the effects of poisons on specific organs by analyzing autopsy materials for poisons and their associated tissue damage. 

The 20th century was marked by advanced level of understanding of toxicology. DNA (the molecule of life) and various biochemicals that maintain body functions were discovered. Our level of knowledge of toxic effects on organs and cells is now being revealed at the molecular level. It is recognized that virtually all toxic effects are caused by changes in specific cellular molecules and biochemicals.  

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The Victorian Search for Gorillas, Evolution, and Humanness

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du Chaillu hunts gorilla

In 1857, less than two years before the publication of On the Origin of Species, Richard Owen delivered a lecture about gorillas. As Europe’s preeminent zoologist / public intellectual—a Carl Sagan of the Victorian era—Owen’s opinion carried a lot of weight. And in his opinion, the brains of man and gorilla differed so greatly that the two species could not be linked by “transmutation” (evolution). In other words: humans did not descend from apes, and the brain was the anatomical bulwark that separated man from beast. It was an argument for human exceptionalism and against Darwinian evolution.

Owen was wrong, but his idea is emblematic of a larger conflict. A paradigm-shifting concept—evolution by natural selection—was meeting a profoundly hierarchical society obsessed with quantifying distinctions in race, class, gender, culture, and ability. The gorilla was right in the middle, and what followed was Victorian England’s “gorilla wars.”

• • •

When Owen delivered his…

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Once Upon a Time

The Oldest Vocation

In 1955, right out of college, I found one of those jobs in publishing so dear to history and English majors who could afford them. We were paid almost nothing, which was considered OK for girls, at least if they had parents who could give them a winter coat for Christmas and bail them out in an emergency. Health insurance wasn’t necessary in those days, when a visit to the doctor or a prescription for an antibiotic cost very little. If you shared space, you could even rent an apartment in Manhattan; with three roommates, I lived near Second Avenue in the80s. We had a duplex two-bedroom apartment in a funky old house with a lot of charm – and a lot of cockroaches, but who cared? Right above the bathtub on the second floor there was a skylight that offered dirty and difficult access to the roof. We…

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Jenny Diski on Writing, Love, and Cancer

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Photo by Suki Dhanda Photo by Suki Dhanda

We’ve been following writer Jenny Diski for many years at the London Review of Books, and more recently on her WordPress.com blog. Just this past weekend Diski was featured in a profile by Giles Harvey for the New York Times Magazine, about a subject she revealed in her own 2014 essays: she has inoperable lung cancer.

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