Ingestion (of plastic) occurs when an animal or human consumes a piece of plastic, accidently or intentionally. A significant proportion of marine species ingest plastic. Seabirds in particular are known to ingest more plastic particles than any other animals: Studies suggest that plastic trash is found in 90% of seabirds. Plastic ingestion is also prevalent in fish, but varies significantly (between 2.6 and 36.5%) depending on the area. The extent of the physical damage caused by ingestion is not yet fully understood, but several health risks are clear, including starvation due to plastic accumulation in the gut. Seabirds are also known to eat sharp edged plastic, which can puncture their gut and cause death. Furthermore, plastic acts like a magnet for persistent, bioaccumulative and toxic (PBT) chemicals or substances that may be present in the water, which can then transfer into animal tissues when ingested.