12,000 to 24,000 tons of plastic are ingested by fish in the North Pacific each year. If blockages do not cause intestinal injury and death , plastic is transferred up the food chain to bigger fish, marine mammals and humans. Exposure to toxic chemicals in plastic such as Bisphenol A leak into the tissue of fish is harmful to humans.
Sea turtles also mistake floating plastic garbage for food. While plastic bags are the most commonly ingested item, loggerhead sea turtles have been found with soft plastic, ropes Styrofoam, and monofilament lines in their stomachs. Ingestion of plastic can lead to blockage in the gut, ulceration, internal perforation and death, even if their organs remain intact, turtles may suffer from false sensations of satiation and slow or halt reproduction.
Hundreds of thousands of seabirds ingest plastic every year. Plastic ingestion reduces the storage volume of the stomach, causing birds to consume less food and ultimately starve. Nearly all Laysan albatross chicks – 97.5 percent, have plastic pieces in their stomachs; their parents feed them plastic particles mistaken for food. Based on the amount of plastic found in our oceans has rapidly increased in the past 40 years.
Marine mammals ingest and get tangled in plastic. Large amounts of plastic debris have been found in the habitat of endangered Hawaiian monk seals, including in areas that serve as pup nurseries. Entanglement deaths are severely undermining recovery efforts of this seal, which is already on the brink of extinction. Entanglement in plastic debris has also led to injury and mortality in the endangered Steller sea lion, with packing bands the most common entangling material. In 2008 two sperm whales were found stranded along the California coast with large amounts of fishing net scraps, rope and other plastic debris in their stomachs.