Tuesday, January 27, 2015

Book review: The Dose Makes the Poison

When I started reading "The Dose Makes the Poison" in the bath, Hero decided it was a very good time to tap on the window.

When that didn't elicit a response, he got a bit vocal.
And roared like a wild beast. It was a VERY short bath.

Can a chemical be good or bad? Is natural better than synthetic? These are important questions raised and addressed in The Dose Makes the Poison: APlain-Language Guide to Toxicology.

The book addresses common concerns about chemicals and drugs, stressing that toxicity is relative and depends on the context. Take anything in a high enough dose and it can kill you. Even water (see this case report, for example).

As the authors state,

“The toxic effects of a given chemical depend on dose (how much), frequency of exposure (how often), and the route by which the chemical enters the body. It always has been thus, and there is no reason to believe it will ever be otherwise. Yet some people find it difficult to believe that chemicals follow any rules at all.”
The book challenges fears about chemicals and drugs, providing useful and very accessible information about what chemicals are, what harm they can cause, what toxicology is, how toxicology studies are conducted and factors that influence the toxic effects of chemicals (such as route of administration, metabolism, excretion and individual factors like gender, age, health and nutritional status of humans and animals exposed). 

It includes some fascinating history, including details about early toxicologists Paracelsus and Ramazzini. (The former refused to be a hoity-toity academic and hung out with labourers, Gypsies and other types avoided by genteel folk, and was killed due to wounds sustained in a pub brawl at the age of 48; the latter specialised in epidemiology and wrote an early textbook on occupational diseases. He hung out with those he wrote about – visiting workplaces like mines, factories and cesspools to experience the conditions in which people worked, and argued for better working conditions).

The book provides an excellent introduction to toxicology and addresses a lot of common concerns about risks associated with chemical and drug exposure. It challenges the concept that “natural” chemicals are “good” and “synthetic” chemicals are “bad”.

There are some minor factual errors, such as the comment that horses are unique in their inability to vomit (there are a few other species that can’t vomit, such as rabbits) and a bold statement that no one ever overdosed on liver (they have, and it can lead to vitamin A toxicity which is one reason for limiting liver in the diet).

The ethical implications of toxicology studies, though raised, could have been explored a little further, particularly around the subject of animal use and alternatives. Given the millions of animals used in toxicology studies, this is a major animal welfare issue with scope for massive reduction in suffering.

Nonetheless, the overall aims of the book are noble: to inform people how toxicology is studied, explaining its limitations, and encourage them to be informed consumers of the literature.

A good book for general readers with an interest in science, anyone interested in toxicology, pharmacology, chemicals or poisons.


Frank P & Ottoboni MA (2011) The Dose Makes the Poison: A Plain-Language Guide to Toxicology (3rd edition). John Wiley & Sons, New Jersey.