Rogue's gallery

Thought to have been one of the factors that caused the downfall of the Roman Empire.

Used in Nazi gas chambers, and, until a few years ago, for execution in certain U.S. states.

A food additive associated with "Chinese restaurant syndrome"

This drug, taken by pregnant women to relieve nausea and insomnia, resulted in thousands of children being born with serious deformities.

These strong, resistant fibres were used in a variety of manufactured goods, such as buliding materials, insulation, friction products (e.g. brake pedals) and heat resistant fabrics. Unfortunately, the fibres can enter the air and lungs, where they can cause serious illness.

Once widely used to control insect pests, such as malarial mosquitoes, but banned in many countries when it was shown to cause reproductive problems in animals (such as thin shells in birds’ eggs), and to build up in the fatty tissues of fish, birds and mammals. It may also be a risk to human health

The Mad Hatter in Alice in Wonderland was probably exposed to this poisonous substance.

The best known of the culprits responsible for the ozone “hole”.

Called the “silent killer”, because you can’t see, smell or taste it, and it doesn’t irritate the skin or mucous membranes. It’s usually what kills when suicides choose death by vehicle exhaust inhalation.

Deliberately spread through the U.S. postal system in 2001.