Once in the ocean, plastic litter affects the safety of sea transport, fisheries, tourism and recreation. When broken up into tiny pieces, plastic attracts toxic chemicals released over decades from industry and agriculture, the concentration of which increases as they move up the food chain.

Exposures to these chemicals have been suggested to contribute to some cancers, and infertility, as well as immune, metabolic, cognitive and behavioural disorders. The entry of plastic pieces into our food chain is of concern to human health.