What are ‘forever chemicals’ and why are they causing alarm?

Madeleine Finlay speaks to environmental journalist Rachel Salvidge about PFAS, also known as ‘forever chemicals’, which have been found at high levels at thousands of sites across the UK and Europe. Rachel explains what they are, how harmful they can be, and what can be done to mitigate their effects. Help support our independent journalism at theguardian.com/sciencepod