Microplastics in the atmosphere: Are they a health risk?

Dr KK Aggarwal

(Medscape excerpts): Microplastic particles have already been detected in seawater, mussels, seafood and fish, as well as in drinking water. Now researchers have found high concentrations of microplastics even in the snow of the Arctic and the Alps.

A study by Dr Melanie Bergmann and Dr Gunnar Gerdts from the Alfred Wegener Institute (AWI), Helmholtz Centre for Polar and Marine Research in Germany shows that the atmosphere absorbs these tiny particles, transports them over long distances and then washes them out of the air again through snow. The study results were published on the 14th August in Science Advances.

A study published in Nature Geosciences in April this year showed that in a remote mountainous region in the Pyrenees, it rained more than 350 microplastic particles per day per square metre – even though there are no large cities or industrial facilities nearby. In 2015, French scientists were able to prove that rain and sewage in Paris contained microplastic particles.

A large quantity of microplastics gets into snow through the air. Some of it probably comes from Europe. The theory is supported by older studies on pollen grains. These, too, can reach the Arctic through the air. Pollen is similar in size to microplastic particles. Saharan dust is also capable of covering distances of 3500 km or more, as far as the Northeast Atlantic.

Inhalation risk?

Microplastics not only reach humans via the seas, but also through the air.

Prof Kelly and colleagues examined 50 pupils at Lordship Lane Primary School in Haringey, north London, and concluded that children's lung development was being inhibited by the release of microplastics from car tyres.

One of the few works is a Danish study published in Scientific Reports in June. Whether, and to what extent, indoor atmospheres are contaminated with microplastic particles, was investigated using a breathing thermal manikin (an anatomical model of the human body). Samples were taken from three flats and analysed using Fourier Transformation Infrared Spectroscopy (FTIR Spectroscopy). All samples were contaminated with microplastics, with concentrations between 1.7 and 16.2 particles per cubic metre.

The study suggested that microplastic particles represent a non-negligible proportion of indoor air particles that can be inhaled and have negative health effects. Polyester was the predominant synthetic polymer in all samples (81%), followed by polyethylene (5%) and nylon (3%).

On the 22nd August 2019, the World Health Organisation (WHO) issued an assessment on the risk of microplastics in drinking water. It concluded there is no evidence so far that they pose a risk to humans.

Dr KK Aggarwal

Padma Shri Awardee

President Elect Confederation of Medical Associations in Asia and Oceania (CMAAO)

Group Editor-in-Chief IJCP Publications

President Heart Care Foundation of India

Past National President IMA