India meets with the founder and director of Chem Trust, Elizabeth Salter Green, and Shruthi Mahalingaiah who is an Assistant Professor of Environmental Reproductive and Women's Health at the Harvard T.H Chan School of Public Health, to discuss the implication of modern day synthetic chemicals on the menstrual cycle and the natural world. Credits: Presented by: India Rakusen. Producer: Ellie Sans. Assistant Producer: Jorja McAndrew. Executive producer: Suzy Grant. Original music composed and performed by Rebekah Reid. Sound Design by Charlie Brandon-King. Special thanks to all contributors and audio diarists. A Listen Production for Radio 4 and BBC Sounds.