Beaches in the UK are seeing an influx in pebbles. But they are no ordinary stone.
These pebbles are made of plastic that has melted and combined with other matter like sand, shingle, seaweed, etc.
These pebbles are called pyroplastic and they form when plastic items are thrown into fire, barbeques or bonfires.
They form lumps of plastic and are smoothened out to a more pebble-like size after they face the direct onslaught of water.
The plastic pebbles blend seemlessly into the stone pebbles on the beach. Image credit; CORNISH PLASTIC COALITION
'Pyroplastics are evidently formed from melting or burning of plastic and are distinctly different from manufactured marine plastics in terms of origin, appearance and thickness,' said the researchers.
Researchers came to know about these pebbles after volunteers from an environmental charity collected them on the Cornwall beaches.
They studied 165 chunks of this plastic form the Whitsand bay. After these pebbles were posted about on social media, 30 rocks were found in Scotland, County Kerry in Ireland and North Western Spain.
Further tests revealed that some rocks were made of soft plastic like those used to make plastic bags that are used to wrap and carry fruits and vegetables. Other pebbles were made of hard plastic used to make plastic pots, containers.
They found out that a chemical additives used in the plastic that forms the rocks are leaking lead into the oceans. Researchers found chromium as well as lead chromate, a compound of lead and chromium that is used to give plastic a yellow, red, or orange hue. The exposure to this can be harmful to the health of a human being, particularly to children and unborn babies.
Levels of the chemicals exceed safety limits set by the European Union that came into force in 2003, suggesting the pyroplastics are older.
This plastic can be eaten by animals and might have already entered the food chain. More research is needed to find out whether this is the case and, if so, how widespread the problem is.
The finding from this study was published in the journal> Science of The Total Environment.