Personal protection equipment was adopted during the COVID-19 pandemic to reduce transmission of the virus. However, masks, gloves and wipes must be disposed of responsibly. Anecdotal accounts of litter throughout 2020 suggest an environmental legacy to mismanaged PPE. Here we show the emergence of COVID-related litter over a 14-month period using the citizen science application Litterati. Observational data suggests that face mask litter became a new litter type as a result of COVID-19 legislation, increasing from <0.01% to over 0.8% in the countries observed. Glove and wipe litter was already prevalent at around 0.2% prior to the pandemic, doubling to around 0.4% throughout the pandemic. Citizen science enabled observation of littering behaviours between nations, highlighting where transferable practice could be beneficial in reducing littering impacts in other nations.