The need for food labelling

In the 19th Century, manufacturers added all kinds of unpleasant substances to processed food.

Milk sellers in the US once added chalk or dye to make their watered-down batches look more palatable. Other food companies added copper sulphate - a garden pesticide - to their tinned vegetables to make them look greener. Formaldehyde or borax was added to extend shelf life. In England, green sugary sweets were coloured with arsenic, and lead was added to red or yellow ones.