Plastics are forever
From: Robin Blackstone, ENN.com
EDITOR’S NOTE: Our local state Representative Donna
Walsh sponsored state legislation to curb marine waste, especially
plastics. Unfortunately, the General Assembly did not enact it. But Donna is a
patient and persistent legislator.
This is no news flash,
but plastics don't biodegrade. And yet almost 50% of it never sees a landfill.
Worse, approximately 80% of the plastic debris in our oceans comes from the
land.
Plastics inevitably
become part of our ecosystem from top to bottom. Of course, we think of the
most pure environments as those in the highest mountaintops.
Generally, we have hypothesized
that water starts pure and becomes more polluted with each tier of drainage but
recent research suggests that we are not starting with as clean a slate as we
thought.
Researchers have
recently found an alarming number of microplastics in Lake Garda, a subalpine
lake located in the Adamello-Presanella Mountains, a part of the Italian Alps.
The microplastics found in Lake Garda were a surprise because of its elevation;
researchers had anticipated pure unpolluted waters.
Microplastics, small
pieces of plastic, typically less than 5 millimeters (0.2 inches) in size come
from a variety of man-made sources. Some of it is produced when large pieces of
plastic breakdown in the environment.
Other types come from
synthetic fibers broken down from clothing, other consumer and personal care
products as well as construction materials.
Researchers led by
Christian Laforsch of the University of Bayreuth in Germany conducted the Lake
Garda study and found the numbers of microplastic particles in sediment samples
from Lake Garda were similar to those found in studies of marine beach
sediments.
Laforsch said, "The
mere existence of microplastic particles in a subalpine headwater suggests an
even higher relevance of plastic particles in lowland waters." Ingestion
into the food chain is likely to blame.
"Next to mechanical
impairments of swallowed plastics mistaken as food, many plastic-associated
chemicals have been shown to be carcinogenic, endocrine-disrupting, or acutely
toxic," said Laforsch.
"Moreover, the
polymers can adsorb toxic hydrophobic organic pollutants and transport these
compounds to otherwise less polluted habitats. Along this line, plastic debris
can act as vector for alien species and diseases."
Half a world away other
microplastic studies are being conducted on the Great Lakes. Sherri Mason,
Associate Professor of Chemistry at the State University of New York (SUNY) is
measuring the incidence of microplastics in the Great Lakes. Initial studies on
Lakes Superior, Huron and Erie were completed in 2012.
The remaining two, Lakes
Ontario and Michigan will be complete this year. The highest number of
microplastic particles so far has been found in Lake Erie where more than
600,000 pieces per square kilometer were found in parts of the lake.
Because microplastics
are not biodegradable, they persist in the environment for many years. When
entrapped within the sediment they are likely to persist for decades. Clearing
the pollution is likely to be expensive and difficult.
Regardless of which body
of water is being tested though, all of the contributing scientists are
concerned that ingested microplastics may impair the ability of organisms to
feed, leading to disruptions in aquatic food webs.
Additionally,
microplastics are likely to play a role in the transfer of chemical
contaminants into aquatic biota affecting all of the world's ocean and
watersheds.