Nina Gomes recovers a discarded plastic bag from ocean waters, near Copacabana beach in Rio de Janeiro, Brazil, in March 2024.

People unknowingly ingest microplastics from what we eat, drink and breathe. Some scientists fear exposure to microplastics could increase vulnerability to heart disease, cancer and other illnesses. While possible links between microplastics and disease are not definitive, researchers are exploring some concerning hints.