Paying with plastic

We live in a sea of these fragments, from which there is no escape, and the possible consequences on our health remain unclear. MARK PATRICK TAYLOR, chief environmental scientist at Australia's Environment Protection Authority Victoria

- Natasha Rego

They are, quite simply, everywhere. There are microplastics in our sugar and salt (in every Indian brand tested, a study found in August). They are in the clouds, on standing crops, in the air, water and soil.

The tiny granules have been detected in human blood, lungs, semen, and in the placenta meant to shield an unborn child. Microplastics are technically any bits of plastic debris less than 5 mm in length or diameter (that's about double the size of a grain of sugar).

They were first categorized as a pollutant 20 years ago, by marine biologist Richard Thompson, who noticed such fragments in the debris washing up on the shores of the remote Isle of Man. ("See the interview alongside for more on this discovery, and his journey since").

"There were bits that were too small to see, but it was pretty obvious that the big bits were becoming small bits and then smaller bits," says Thompson, who now heads the University of Plymouth's International Marine Litter Research Unit.

He coined the term and began talking about how these pollutants could wreak havoc on marine life, and end up in the food chain.

He was right, of course. The study conducted recently in India, by the environmental research organization Toxics Link, found between 6 and 89 pieces per kg of salt and sugar, in the form of fibre, pellets, films and fragments. (Other studies in other countries have come away with similar strike rates.)

So how did they get everywhere?

Before Thompson's research, while it was known that plastics do not decompose, no research was focused on how they "shed" as they degrade.

Exposure to friction, ultraviolet light, heat or pressure can cause infinitesimal fragments to break off and drift away.