NBC News

As a knife’s blade scratches a plastic cutting board’s surface, tiny pieces of plastic get released that stick to your ingredients — they’re too small to see, so you may ingest them, says Dr. Manish Shetty, an assistant professor of chemical engineering at Texas A&M University. Particles that stick to the knife’s blade or cutting board go down the drain when you clean them, so there’s an environmental impact to consider, too. That said, how worried should you be?