Travelling nurdles map plastic peril
Boffins use Durban disaster to track ocean pollution
● A silver lining has materialised from a major environmental disaster that struck Durban when a superstorm resulted in more than 2-billion plastic pellets falling out of a container from a ship moored in the harbour two years ago.
About a third of the pellets — known as nurdles — beached along the coastline and were cleaned up by a pollution control company, for which the Mediterranean Shipping Company footed the bill.
Those that didn’t make landfall have travelled great distances, some ending up on Western Australian beaches, others on remote St Helena island in the South Atlantic.
2.25bn THE ESTIMATED NUMBER of nurdles that fell into the Durban harbour in 2017 8,000km THE APPROXIMATE DISTANCE travelled by the ‘Durban’ nurdles to Western Australia
Many nurdles may still be drifting in other parts of the world.
The trajectory of the nurdles has given oceanographers insight into how currents carry plastic pollution around the oceans — one of the most pressing environmental concerns facing the world.
It also provides a case study into who should be responsible for cleaning them up.
The tiny pellets are of concern to scientists because they soak up pollutants and become toxic. Marine animals and seabirds mistake nurdles for food and they enter the food chain.
Two oceanographers, Lisa Guastella in Durban and Harriet Paterson in Albany, Western Australia, have tracked the travelling Durban nurdles.
Guastella said some of the Durban nurdles that didn’t beach locally were drawn into the Agulhas current, which flows southward off the South African coast before joining the flow from Africa to Australia.
By analysing drifter buoys at the time, Guastella was able to predict it would take about 500 days for the first nurdles to wash up on Australia’s southwest coast.
She contacted Paterson to alert her that should the nurdles beach in Australia, they would be of interest for scientific research.
“Initially it may have been a local problem but because these little things can float away on the ocean currents it can become a global problem,” said Guastella.
Paterson, who has been collecting and analysing all types of nurdles that have washed up on Western Australian beaches, started the Durban project after the spill.
“It is unusual to know where a spill like this happens, so we should use it to understand more about pollution and how it moves in the ocean,” Paterson told the Sunday Times.
She said the Durban nurdles — small, opaque and pancake-like in shape — were different from the ones she usually found.
“There are many people along the south coast of Western Australia who are looking for nurdles, some just to count what is there and some are looking to find Durban nurdles.
“We have taken nurdles that look like the Durban ones from the beach to the lab and looked at them using scientific equipment. The ones we have looked at have the same chemical signature as the reference nurdles from Durban.”
Though the numbers are small, Paterson said she would continue to collect them and expects their numbers to increase.
Paterson warned that the nurdles could be dangerous to marine life and humans.
“Nurdles look like fish eggs and eyes, which are high-protein foods for fish and birds.
“They cause problems for animals by replacing food, blocking intestines. [Animals] may also absorb toxic chemicals from the nurdles, which enter the food chain and eventually end up in us.
“This is then a problem for all of us,” said Paterson.