Chemical 'canaries': Munitions workers in the First World War.

In the early twentieth century, scientific innovations permanently changed international warfare. As chemicals traveled out of laboratories into factories and military locations, war became waged at home as well as overseas. Large numbers of women were employed in munitions factories during the First World War, but their public memories have been overshadowed by men who died on battlefields abroad; they have also been ignored in traditional histories of chemistry that focus on laboratory-based research. Mostly young and poorly educated, but crucial for Britain's military success, these female workers were subjected to procedures of social regulation and consigned to carrying out dangerous chemical procedures causing chronic illness or death; in particular, when TNT died their skin yellow, they were colloquially known as 'canaries.'