Preservatives are added to many things we use every day - from food and drink, to cosmetics and medicines.

They are added to prevent these products breaking down quickly or being contaminated by bacteria and yeasts, which means they last for longer and don't have to be replaced frequently.

Methylisothiazolinone (MI) is a preservative commonly used in a range of consumer products, including cosmetics, but dermatologists have long been concerned about a rise in the number of people having allergic responses to it.

Smitha Mundasad reports from Edinburgh, where one woman told her how the allergy affects her life.