Kat Arney unearths the story of a truly international effort to develop new drugs for cancer, and the female researcher whose key role went overlooked

Kit Chapman on the simple polymer that preserves and protects ancient artifacts, and saved a historical Swedish shipwreck from complete collapse

Mike Freemantle on the iron compound that has been turning oak gall extract into indelible ink for centuries, but is now eating though our ancient manuscripts and musical scores

The mysterious enzyme that can beat the world's biggest chemical process when it comes to breaking the dinitrogen triple bond

A brilliant rich blue rock, prized in antiquity as a gemstone and a prominent pigment, lazurite is the basis of lapis lazuli, the original ultramarine paint and – as Brian Clegg finds – it even adorns Tutankhamun's death mask.

Cases of sleeping sickness – human African trypanosomiasis – are in decline, dropping 86% in Africa between 2000 and 2014. Gege Li explores the role that this toxic, arsenic-based medication has to play.

Many consume cod liver oil due to 'a vague sense we should be taking them for something' – but what to the omega-3 fatty acids actually do?

It made Robert Bunsen seriously ill, Michael Faraday thought it 'barbaric' to use in battle and even Fritz Haber – the 'father of chemical warfare' – abandoned it after a fatal accident in his lab. This week, Mike Freemantle tells the story of tetramethyldiarsine, otherwise known as cacodyl.

Kit Chapman takes us back to the 1904 Olympics in St Louis, via the bronze age and ancient Greece

Louise Crane introduces the antioxidant that led to exaggerated claims that 'whisky helps fight cancer'