Sailors testing the waters during the Ocean Race, which travels through some of the world’s most remote ocean environments, have found microplastics in every sample.
Up to 1,884 microplastic particles were found per cubic metre of seawater in some locations, up to 18 times higher than in similar tests during the last Ocean Race, which ended in 2018. Scientists noted that the sensitivity of their instruments is now higher.
“It’s really concerning that we are finding microplastics in every sample, from coastal areas to the most remote regions of the ocean,” said Victoria Fulfer, a visiting scientist from the University of Rhode Island at the National Oceanography Centre (NOC) in the UK. “We are seeing much higher concentrations this year, which can be a sign of increased pollution, but also is related to the increased sensitivity of our analysis.”
The samples were collected during the initial legs of the race, which started in January and finishes in July, passing through the South Atlantic Ocean near a location considered to be the farthest from land anywhere on Earth.
The 45 samples collected from leg two, running from Cabo Verde to South Africa, showed microplastic concentrations from 92-1,884, while in leg three – between Cape Town and Itajaí, Brazil – the concentrations ranged from 160-1,492 per cubic metre.
A filter on the boats can pick up plastic particles measuring between 0.03mm and 5mm. The samples are sent daily to the NOC for analysis, with support from the University of Rhode Island.
The highest concentrations of microplastics were found close to coasts and urban areas, such as readings of 816-1,712 per cubic metre off the coast of South Africa, and also in the “garbage patch” areas of the sea, where currents cause plastic to accumulate. Concentrations during the 2017-18 Ocean Race ranged from 50-100 per cubic metre.
Samples taken near the planet’s most remote area, Point Nemo, which is 2,688km (1,450 nautical miles) from land in all directions, revealed 320 microplastic particles per cubic metre, compared with 9-41 in the last race.
The most abundant chemical in the plastics is polyethylene, which is used for single-use packaging, plastic bags and containers such as bottles.
Fulfer expressed dismay at the high concentrations nearer to shore. “This is really concerning because coastal areas are so vital for fisheries production and the blue economy,” she said. “All these microplastics are available for organisms to ingest, which could then impact our health.”
The microplastics research is part of a science programme being conducted during the 62,000km Ocean Race, with sailors collecting data such as sea temperatures, CO2, oxygen and trace elements in locations scientific research vessels can rarely reach, and sharing it with a number of science organisations and publicly at theoceanracescience.com.
