On 1 July 1918, the National Shell Filling Factory No 6 (Chilwell, near Nottingham, England) was partly destroyed when 8 tons of TNT exploded in the dry mix part of the factory. Approximately 140 workers – mainly young women, known as the 'Chilwell Canaries' because contact with TNT turned their skin yellow – were killed, though the true number has never been satisfactorily established.