The micro plastic particles found in London are large enough to be deposited on to the airways when inhaled.
The micro plastic particles found in London are large enough to be deposited on to the airways when inhaled.
Micro plastic pollution is raining down on city dwellers, with research revealing that London has the highest levels yet recorded.
The health impacts of breathing or consuming the tiny plastic particles are unknown, and experts say urgent research is needed to assess the risks.
Only four cities have been assessed to date but all had micro plastic pollution in the air. Scientists believe every city will be contaminated, as sources of micro plastic such as clothing and packaging are found everywhere.
Recent research shows the whole planet appears to be contaminated with micro plastic pollution. Scientists have found the particles everywhere they look, from Arctic snow and mountain soils, to many rivers and the deepest oceans. Other work indicates particles can be blown across the world.
Stephanie Wright from Kings College London, who led the research, said that “The level of micro plastic discovered in the London air surprised scientists. “We found a high abundance of micro plastics, much higher than what has previously been reported but any city around the world is going to be somewhat similar.”
About 335m tonnes of new plastic is produced each year and much leaks into the environment. The research, published in the journal Environment International, collected the micro plastics falling onto the roof of a nine-story building in central London. This ensured that only micro plastic from the atmosphere was collected.
They were found in all eight samples, with deposition rates ranging from 575 to 1,008 pieces per sq metre per day, and 15 different plastics were identified. Most micro plastics were fibres made of acrylic, most likely from clothing. Just 8% of the micro plastics were particles, and these were mostly polystyrene and polyethylene, both commonly used in food packaging.
The rate of micro plastic deposition measured in London is 20 times higher than in Dongguan, China, seven times higher than in Paris, France and nearly three times higher than Hamburg, Germany. The researchers do not know the reason for the variation, but differences in experimental methods are likely to be partly responsible.
The micro plastic particles in London were between 0.02mm and 0.5mm. These are large enough to be deposited on to the airways when inhaled and would be swallowed in saliva. Smaller particles that can get into the lungs and bloodstream represent the greatest potential health hazard. These were seen in the samples but their composition could not be identified with current technology.
The serious health damage caused by the pollution particles emitted by traffic and industry are well known. A comprehensive global review earlier in 2019 concluded that air pollution may be damaging every organ and virtually every cell in the human body.
Plastics can carry toxic chemicals and harbour harmful microbes, and the limited research done to date has shown harm to some marine creatures. The only assessment of micro plastic in human lungs, published in 1998, found inhaled fibres were present in cancerous lung specimens.
Steve Allen at the Eco Lab research institute near Toulouse, France, and whose own work has shown micro plastic air pollution in remote mountain areas. The London research is a very well done study showing incredibly high numbers of airborne micro plastics.
He said that currently we have very little knowledge on what effect this airborne pollution will have on humans. But with what we do know it is pretty scary to think we are breathing it in. We need urgent research.
Johnny Gasperi at the Université Paris-Est, said the research shows a widespread contamination of the air by micro plastics. He said the London study showed that micro plastic deposition did not depend on the strength or direction of the wind, suggesting the city itself was the most likely source.