Marine food web at risk due to microplastics: NCPOR study
Marine food web at risk
due to microplastics: NCPOR study
New Delhi (India Science Wire): During the recent times, microplastics are posing
a serious ecological threat to the world's oceans and seas. Microplastics
pollution is even extending to the remote areas of oceans far away from human habitats.
A study conducted by Periyar University and National Centre for Polar and Ocean Research (NCPOR) at the Silver Beach, which is a beach on the
southeast coast of India, renowned for its rich marine biodiversity, has brought
to the fore some newer dimension of the multitude of the problem. The study recorded
the highest amount of colored plastic particles on the beach compared to fragmented
and irregular shaped plastic particles polluting the beach.
Microplastics are
plastic pieces smaller than 5 mm which are further classified into primary and
secondary microplastics. Primary microplastics are the smaller plastics produced
for industrial purposes, mainly for cosmetic industries whereas secondary
microplastics are created when larger plastic items break down into smaller
pieces in oceans by sunlight and wave action. These tiny pieces of plastic
debris can enter marine food chains and potentially pose huge risks to human
health too.
The result of the study
suggests that untreated urban sewage, tourism and fishing activities are
sources of the plastic debris and storm-water runoff plays a significant role
in the transportation of plastic debris through the Gadilam river and
wave-induced deposition through high tides. NCPOR suggests that only radical remedial
action can eliminate the problem at the source itself to stop further damage to
the ecosystem and human health. In the last 70 years, there is a two
hundredfold increase in the production of virgin plastics, of which only a
small portion is recycled, and about a third of all the plastic wastes end up
in nature. Worldwide, the amount of plastic trash that flows into the ocean
every year is expected to nearly triple by 2040 to 29 million metric tons.
It has been observed
that plastic pollution gets aggravated due to the passage of persistent
chemicals like pesticide Dichlorodiphenyltrichloroethane (DDT) and toxic
Polychlorinated Biphenyls (PCBs) making them more concentrated when they come into
contact with marine life.
When microplastics get
abundant in a polluted area, owing to their greater surface to volume ratio and
their hydrophobic nature, they get easily associated with other organic and metal
pollutants on the ocean surface, near the mouths of rivers, coasts and even in
deep-sea sediments. As a result of this, there is an increased level of
pollution spreading to all the areas of the ocean. The entire marine food web
succumbs to this due to the ingestion of these pollutants by marine organisms
and even poses a great threat to human health.
Highlighting the
characteristics and distribution of plastic pollutants in Silver beach caused
by terrestrial debris deposition mainly from the inflow of river Gadilam, the
study suggested that effective remediation can be possible through policy
formulation to minimize plastic use, reducing the use of single-use plastic and
their proper disposal. The study emphasized the need for future assessment of
microplastics on ecologically sensitive organisms around the study area.
Led by Magesh, N. S., Scientist at NCPOR, Ministry of Earth Sciences, and research team comprised of. Vidyasakar, A., Arun Bharathi V., and Prabha, K. of Periyar University PG Extension Centre, Dharmapuri, Krishnakumar, S. Kasilingam, K and Neelavannan K. of the University of Madras, Guindy Campus, Chennai, and Prince, S. G. of the University of Kerala, Kariavattom Campus, Thiruvananthapuram. The research paper is published in the Marine Pollution Bulletin.
(India
Science Wire)