Plastic-rock hybrids found on the Andaman Islands

Subject : Environment

Section: Pollution

Context:

A new study by the Indian Institute of Science Education and Research, Kolkata, found the first record of plastiglomerates in the Indian sub-continent on Aves Island in the Andaman archipelago.

Details:

The samples studied contained polyethylene and polyvinyl chloride mixed with rock and sand, and were possibly a result of solid waste burning in the open.
Plastiglomerates or plastic-rock hybrids are formed when plastic pollution mixes with organic or inorganic material and forms rocks through geological processes.
Location:
- The samples are found at Aves Island, located at 3.5 kilometres east of Mayabunder, a town in the north Andaman district.
- The Island harbours mangroves, coral reefs, seaweed and rocky outcrops.
How are they formed?
- when the plastics, in the form of burnt litter, mixes with conglomerates, which are sedimentary rock made up of fragments like pebbles, sand, and silt.
Are they found elsewhere?
- First reported from Hawaii in 2014,plastiglomerates have subsequently been found in Indonesia, Portugal, Canada, Peru, Brazil, and now India.
Impact:
- With plastic entering the rock cycle and potentially remaining for thousands of years, the researchers believe that plastiglomerates act as an ‘Anthropocene marker’, which means they reflect the impact that humans are having on the planet.

Where did plastiglomerates originate?

The location of the island and the pattern of the ocean current may have played a role in the formation of the plastiglomerate.
The researchers believe that the plastic waste found here is brought through the deep current system in the northern part of the Indian ocean and the Andaman sea and deposited along the coastlines or trapped in intertidal areas.
The findings from the present study opens up possibilities to understand the fate of plastic polymers embedded in rocks on marine biota and how plastic particles may end up in the food chain through biomagnification.

How can we mitigate the formation of plastiglomerates?

The Port Blair Municipal Council (PBMC) is the only urban local body responsible for the management of solid waste from the Andaman and Nicobar Islands.
While the PBMC ensures door-to-door collection of waste from all households, there are no sewage treatment plants, and both untreated liquid waste, as well as unmanaged solid waste, are dumped into the drains.