Scientists have claimed balloons present a global threat to marine life, as they are 32 times more likely to kill seabirds than hard plastics if ingested.
Researchers from the Institute for Marine and Antarctic Studies, The Commonwealth Scientific and Industrial Research Organisation, and the Antarctic Climate and Ecosystems Cooperative Research Centre examined the cause of death of 1,733 seabirds from 51 different species, concluding that one in three had ingested marine debris.
Whilst soft plastics, such as balloons, accounted for only five percent of the items ingested, they were responsible for nearly half (40 percent) of the deaths.
The leading cause of death was found to be blockage of the gastrointestinal tract, followed by infections or other complications caused by gastrointestinal obstructions.
'A critical step'
Scientist Dr Wilcox said: "These two applications are the first time there has been a robust estimate of the impact of plastic ingestion on free-living marine species.
"This is a critical step in triggering action to address plastic pollution."
'Even a single piece can be fatal'
Leader of the study, Dr Lauren Roman, said: "If seabirds eat plastic their risk of mortality increases, and even a single piece can be fatal.
"While hard plastics are less likely to kill than soft plastics they were still responsible for more than half of the seabird deaths identified in our study.
"The evidence is clear that if we want to stop seabirds from dying from plastic ingestion, we need to reduce or remove marine debris from their environment, particularly balloons."