Microplastics in the oceans are becoming a notorious area of study with increasing concerns on how it affects the food chain. New research has revealed that these microplastics are now becoming airborne from polluted waters via flying insects, affecting birds and other insect eating creatures.
Microplastics are a pervasive pollutant found in marine, freshwater and terrestrial ecosystems. By definition, they are plastic particles that are less than five millimetres in size and are categorised into two sources: primary and secondary. Primary sources are the direct release of microplastics into the environment while secondary sources are a result of the degradation of macroplastics. They enter into the ecosystem in various shapes and sizes from pellets, fibres and cosmetic beads.
The research led by Rana Al-Jaibachi from the University of Reading, experimented on Culex pipiens mosquito larvae where they fed the universally common mosquito fluorescent polystyrene beads. It was concluded that the beads of two micrometres were readily transferred during the larvae’s metamorphosis from pupa to adult.
“Larvae are filter feeders that waft little combs towards their mouths, so they can’t actually distinguish between a bit of plastic and a bit of food”, said Professor Amanda Callaghan from the University of Reading. “They eat algae, which are more or less the same size as these microplastics”.
This reaffirms that microplastic pollution will harm ecosystems as it can be transferred up the food chain, placing all organisms in the upper trophic levels at risk.
“It is a shocking reality that plastic is contaminating almost every corner of the environment and its ecosystems”, said Prof Callaghan. “Much recent attention has been given to the plastics polluting our oceans, but this research reveals it is also in our skies”. This means that terrestrial birds that eat insects and not-at-risk animals on land will be exposed to microplastics via flying insects.
The most concerning part is that Prof Callaghan confirms that humans are also consuming microplastics. From seafood, beer, sugar to sea salt, all these food products contain microplastics. With an expected 40 per cent increase in plastic production in the next decade, this calls for crucial research on the consequences of people ingesting microplastics.