“Mad as a Hatter” and the ASP exam

Anyone who has seen the animated movie Alice in Wonderland knows that it features an eccentric character called the Hatter, referred to in the story as “mad” and became popularly known as the Mad Hatter. However, the phrase “mad as a hatter,” used to describe someone crazy or prone to unpredictable behavior, didn’t originate with Lewis Carroll’s novel. Instead, the expression is linked to the hat-making industry and mercury poisoning. In the 18th and 19th centuries, industrial workers used a toxic substance, mercury nitrate, to turn the fur of small animals, such as rabbits, into felt for hats. Prolonged mercury exposure caused employees to develop a variety of physical and mental ailments, including tremors (dubbed “hatter’s shakes”), speech problems, emotional instability, and hallucinations.

Mercury, a heavy metal, is classified within industrial hygiene as a potent neurotoxin. This classification is due to its significant impact on the central nervous system. Other heavy metals, such as lead, arsenic, and manganese, are also considered highly neurotoxic agents, further emphasizing the importance of understanding their effects in the field of industrial hygiene.

The term “neurotoxin” is one of the toxins that may show up on the ASP and CSP exams. Other toxins that may show up include:

The term “neurotoxin” is one of the toxins that may appear on the ASP and CSP exams. Other toxins that may show up include:

Chemicals that produce liver damage, including symptoms such as jaundice and liver enlargement, are known as hepatotoxins. Signs and symptoms include jaundice and liver enlargement. Chemicals: carbon tetrachloride, nitrosamines. In the past, carbon tetrachloride was widely used as a cleaning fluid (in industry and dry-cleaning establishments as a degreasing agent and in households as a spot remover for clothing, furniture, and carpeting). Carbon tetrachloride was also used in fire extinguishers and as a fumigant to kill insects in grain.

Chemicals that produce kidney damage are known as nephrotoxins. Signs and symptoms include edema and proteinuria.  Chemicals: Halogenated hydrocarbons, uranium.

Chemicals that affect the blood are known as hemotoxins. Signs and symptoms include organ collapse and general tissue damage. Chemical benzene.

Industrial hygiene is among the largest domains by the percentage of questions on the ASP and CSP exams. Familiarity with the various toxins, their target organs, and their symptoms is basic knowledge for both exams.

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