It’s not easy to tell whether plastic is being ingested by such creatures intentionally or accidentally. There’s some evidence suggesting that plastic that physically resembles turtle’s food is taken up at a higher rate, but either way, it can cause a range of issues. Sometimes, it’s just excreted harmlessly, but in many others, the turtles’ guts are perforated to lethal effect.
This study marks the first time a numeric relationship between plastic ingestion and lethality has been made. It seems that, if 226 plastic items are consumed, death is certain.
Their results also confirm that eating a low number of plastic pieces may not kill many sea turtles, but it still can kill some through gut impacts or perforations. It could only take one single piece for a sea turtle to perish. In fact, the team places such odds of mortality for a sole segment of plastic being ingested at 22 percent.
Sea turtles are particularly vulnerable to this cause of death. They have a complicated gastro-intestinal tract that allows plastic to get trapped in its nooks and crannies more easily, and they are also unable to regurgitate, meaning that what goes into their throats stays in their throats.
Fortunately, this model has quite broad applications, and its technique could at least be applied to other wildlife. Around 700 species, from seabirds to fish, interact with a wide range of our trash in some way or another. This study, then, provides a starting point to calculate just how deadly some of those interactions are.