In the Volvo Ocean Race Cardiff race village, the Welsh Government signed the country up to the United Nations Environment's #CleanSeas campaign alongside World Sailing and the International Olympic Committee.
Following a video address from Prince Charles, announcements from the Welsh Government, Iceland Foods and new microplastics data from the Volvo Ocean Race Science Programme all helped advance the growing movement to turn the tide on plastic.
The Welsh Government also said that drinking water would be made available along the 870-mile Wales Coast path to help reduce the use of single use plastics.
Iceland Foods Group revealed the extension of their in-store trial of a Deposit Return Scheme. The reverse vending machines accept Iceland's empty plastic beverage bottles and repay customers with a 10p voucher for each recycled bottle, to be used in store.
Meanwhile, Sky Director Robert Tansey, gave a keynote speech on the impact of the Sky Ocean Rescue campaign on the use of single-use plastic and the organisation’s efforts to remove them from their supply chain.
He said: "We're very proud of what Sky has achieved but there's much left to do. Awareness is no longer the issue. We now need to move into action."
And the Volvo Ocean Race Science Programme unveiled microplastics data from Leg 8 of the Race from Itajaí in Brazil to Newport, USA.
The new information, collected by race boats Turn the Tide on Plastic and Team AkzoNobel, found 157 particles per cubic metre close to Itajaí and 71 particles per cubic metre near Newport.
Anne-Cecile Turner, Volvo Ocean Race Sustainability Programme Leader, said: "The series of Ocean Summits are raising the bar as a forum for collective, creative, ground-breaking initiatives to the environmental plastic problem affecting our oceans.
"As an advocacy platform, they are moving this pressing issue up the global agenda, whilst at the same time, increasing public awareness. However, to solve the problem, we must maintain this momentum in order to deliver decisive action that creates long-term solutions."