Guest Essay by Kip Hansen
The New York Times has treated us to another episode of the Great Plastics-Last-Forever Urban Legend in their recent article “The Immense, Eternal Footprint Humanity Leaves on Earth: Plastics” by the incredible Tatiana Schlossberg (here and here).
The New York Times’ article breathlessly reports:
“From the 1950s to today, 8.3 billion metric tons of plastic have been produced, with around half of it made since 2004. And since plastic does not naturally degrade, the billions of tons sitting in landfills, floating in the oceans or piling up on city streets will provide a marker if later civilizations ever want to classify our era. Perhaps they will call this time on Earth the Plastocene Epoch.”
“Their findings suggest that staggering amounts of near-eternal litter is present in the environment — the oceans, landfills and freshwater and terrestrial ecosystems — and the numbers are quite likely to increase, with 12 billion metric tons accumulating in landfills or in the environment by 2050.”
“Scientists estimate that five million to 13 million metric tons of plastic enter the ocean each year, according to previous studies. New data suggests contamination in rivers and streams, as well as on land, is increasingly common, with most of the pollution in the form of microscopic pieces of synthetic fibers, largely from clothing.”
“Dr. Geyer said there was not enough information on what the long-term consequences of all this plastic and its disposal would be. “It accumulates so quickly now and it doesn’t biodegrade, so it just gets added to what’s already there.”
“Once we start looking” Dr. Geyer said, ”I think we’ll find all sorts of unintended consequences. I’d be very surprised to find out that it is a purely aesthetic problem.”
The bolded phrases (my bold) are the Scientific Urban Legend. It simply is not true that “plastics are eternal” or that “plastics don’t bio-degrade”.
This Urban Legend is even less true than the entirely fallacious “Great Pacific Garbage Patch” created whole-cloth, apparently, in 1997 the imagination of Charles J Moore, which he described as “I was confronted, as far as the eye could see, with the sight of plastic. It seemed unbelievable, but I never found a clear spot. In the week it took to cross the subtropical high, no matter what time of day I looked, plastic debris was floating everywhere: bottles, bottle caps, wrappers, fragments.” Of course, there were no photographs.
Slate magazine says “Moore’s Garbage Patch would grow in size and fame in the years that followed. The plastic-plankton soup he’d first discovered in 1997—which oceanographer Curtis Ebbesmeyer dubbed the “Eastern Garbage Patch” or the “Pacific Garbage Patch”—gained notoriety in a 2006 series for the Los Angeles Times that won a Pulitzer Prize. Its area had doubled: Now the patch was “twice the size of Texas.” (Some reports went even bigger.) As coverage intensified—the patch’s media profile peaked between 2007 and 2009—the soup coalesced into a garbage landmass with a more official name: the “Great Pacific Garbage Patch.” In 2007, the San Francisco Chronicle called the patch “a massive, eternal, slowly swirling vortex of noxious garbage the size of a continent and the shape of death itself, just floating out there in the middle of the Pacific Ocean, mocking life, humanity, God.”
Typical of Scientific Urban Legends, the Garbage Patch grew and grew, in size, nature and villainy, each re-telling adding to the size and content and magnifying the horror of it all.
Key to the Legend is the falsehood repeated by Tatiana Schlossberg in her NY Times piece — that plastics are somehow magically eternal, that they do not degrade in the environment, and incineration is the only way to destroy them. A falsehood oddly supported by Dr. Roland Geyer — who ought to know better.
The simple fact is that plastics do degrade in the environment, especially in the ocean (and lakes, streams, rivers).
When real scientists went out to investigate the marvelous Pacific Garbage Patch imaginatively described by Charles Moore, they found — well, almost nothing. They found this:
That’s what I found in the supposed mirror- image Atlantic Garbage Patch…basically nothing showing, nothing to see.
In a previous essay here on this subject, An Ocean of Plastic, I related an email conversation with Dr. Jenna R. Jambeck, one of the world’s leading experts on oceanic plastics and ocean debris, in which she shared with me that on a recent voyage from Lanzarote (in the Canary Islands off the shore of Africa) to Martinique (one of the Windward Islands of the Caribbean), a trip of 3,200 miles, they recorded sighting 15 floating items – “mostly buckets and buoys, with at least one bottle too”. A far cry from Charles Moore’s wholly imagined garbage patch.
The missing garbage patch was such a surprise (outside of portion of society taken in by all things environmental no matter how unlikely to be true) that we began to see some real science on the topic, such as National Geographic’s piece “Ocean Garbage Patch Not Growing—Where’s “Missing” Plastic?” which tells us “It’s possible some of the trash is just too small for researchers to catalog, study leader Kara Lavender Law, an oceanographer at the Sea Education Association (SEA) in Woods Hole, Massachusetts said: “Our net only captures pieces larger than [a third of a millimeter] in size, and it’s certain that the plastic breaks down into pieces smaller than that.” [That was in 2010, Kara Lavender Law is still a leading researcher and advocate in the field of oceanic plastics and oceanic debris.]
Smaller than a third of a millimeter?…..how small is that when the sun comes up in the morning? That’s about 1/4th the thickness of a US dime (10 cent piece) or three sheets of 20 lb. inkjet printer paper. That is really small, in other words. If one was snorkeling in the water
with these suffused with particles of this size, with the tropical sunlight shining down through the water, they would appear as little flecks of something — just like all the other little flecks and bits and incredible little plants and animals that live the floating life in the sea.
This aspect is a real problem actually. To sea life food is often identified by size — moving objects in a certain size range are food and are eaten without further thought or inspection. This is why fishing lures pulled through the water catch fish — right size, right shape (even just sort of), colored to attract attention and right movement equals food. As a result, lots of these little bits are being ingested by fishes and other denizens of the deep. Luckily, most animal life forms are built on the same topology as a tube — what goes in the front (eating) end generally is capable of coming out the other (pooping) end. Things that don’t come out the other end have ways of getting back out the eating end (think cats and hairballs).
There are unfortunate exceptions, like the vanishing small percentage of albatross chicks whose mothers bring them too many shiny bits of colored plastic, as I explained in a previous essay: “Just to clarify, I’ve counted about a dozen different pictures of dead albatross chicks from Midway on the internet, some of them look to be several seasons old. Midway Atoll is the winter home of nearly a million nesting albatrosses. Roughly 450,000 pairs wedge their way into a scant 2½ square miles of land surface. Not very many albatross chicks are dying from being fed plastic. In a Darwinian sense, mother albatrosses who feed chicks too much plastic don’t get to pass on their genes, thus improving the species.”
Some biologists are concerned because some plastics have a tendency to absorb other chemicals from the environment and that organisms ingesting the plastic pieces might be adversely effected by these chemicals. There is as yet no reliable science on this point — it may just be an unfounded fear or it may have some validity.
So, with the studies we have, we can be fairly sure that much more plastic inadvertently ends up in the ocean than can be found and accounted for. The Geyer paper discussed by the NY Times basically is adding up all the plastic produced, subtracting the amounts estimated to be incinerated, recycled and landfilled giving a very broad estimation of how much plastic goes missing and might eventually end up in the ocean. When that plastic is searched for — and believe me, if you review the literature, they have searched and searched for it, there is plenty of research money for this topic — they do not find it. Thus the question remains: Where is that missing plastic?
The studies that search for oceanic plastics, these sea-sifting projects, I believe are ride-alongs, one of many projects being done from a research vessel on its various voyages for various purposes, and consist generally of net-tows (towing sieves with differing sized-holes) through the water for set distances. The contents of the net are then washed, sifted, and sorted by picking through the captured material with long pointed needles and tweezers.
Here is what two different studies find:
Compare that image with this from an earlier study:
The thing to notice in both of these images is the shape of the curve. There are very few big pieces — above 15 mm (about ½ in) (see the bottom scale of the bottom graph) — Isobe finds more of these ½ to 1 inch (15 to 30 mm) pieces in his areas closer to the shores of Japan. The number of pieces rapidly grows as size decreases, as we would expect if items are breaking into 2 or more bits, then those bits breaking in two, etc. Until…..the size hits a seemingly magical point of 1.5 to 1 mm. Then the absolute number of pieces decreases rapidly until we find very few pieces under 0.3 mm (1/3 mm). With our understanding that these bits of plastic are breaking up into smaller and smaller pieces, we would have expected the graphs to show increasing numbers as size decreased. The finding is not a fluke; two independent voyages find the same general pattern.
What can we know from this? It is obvious that the floating plastic items in the sea rapidly break apart into smaller and smaller pieces — objects big enough to be seen from a distance are very rare and seldom turn up in net-tows. But something strange happens when the pieces are reduced to sizes below about 1mm — they start rapidly disappearing. What happens to them? Where do they go?
The potential fate of plastics that have escaped into the wild or landfilled were studied by Swift in 2015, focusing on ways to improve their breakdown in landfills. The potentials fates are shown in this little tree diagram:
Micro-organisms living on the surface of plastics contribute to the degradation of plastics in two ways, as explained in the 2015 paper by Graham Swift (2015):
“It should be recognized that testing of the degradation of plastics and polymers relates to physical and molecular property changes that may be promoted by physical, chemical, and biological processes. The latter is where oxidation is promoted exo-cellularly by certain enzymes with the products generally consumed by the bacteria present, but not necessarily. Biodegradation is distinctly different and is considered to be biological consumption of the plastic or polymer and is measured by the rate and amount of gases, carbon dioxide in aerobic conditions and carbon dioxide together with methane in anaerobic conditions, evolved during metabolic processes.”
In short, one pathway is when the activity of bacteria and other microorganisms aid oxidative degradation which leads to physical degradation which exposes more area to oxidative degradation. In this pathway, the bacteria may or may not consume the products of the breakdown. The second pathway is when the bacteria actually consume the plastic itself.
Ultimately, some plastic may remain unchanged. The common, ubiquitous building material, PVC – polyvinyl chloride, has been found to be almost impervious to breakdown. This is, of course, a good thing and the very reason that it is used for modern plumbing, siding for houses, window frames and as a replacement for lumber in some cases.
PVC is pretty good at standing up to the Sun’s UV — I used some PVC moulding as a replacement rubbing strake on my sailboat about ten years ago and it has performed well despite the tropical sun.
Most other plastics breakdown faster or slower depending on their environment. In landfills, plastic degrades and biodegrades faster when there is plentiful oxygen, and slower where there is not — but, in the end, most common types degrade — they are NOT eternal, they are NOT forever.
As we have seen, floating plastic in the sea rapidly breaks down into smaller and smaller pieces — being exposed to sunlight and the motion of the waves. When the size of the pieces reach a seemingly critical points, smaller than 1 mm, the plastic disappears.
Simply put, it has been known for the last ten years
of or so that the missing oceanic plastic is eaten. Not just by fishes, although certainly some is ingested and re-excreted by fishes, but actually consumed as food by microorganisms.
Swift refers to this as bio degradation (“ Bio-degradation is distinctly different and is considered to be biological consumption of the plastic”).
Here’s what they have found is happening:
The tiny animals actually consume the plastic itself, much in the same way that they ate the oil from the Deepwater Horizon Gulf of Mexico Oil Spill. (Scientific American magazine ran this piece: “Meet the Microbes Eating the Gulf Oil Spill”. )
The same principle involved in the melting of crushed ice vs. cubed ice operates here: the smaller bits have a greater surface area compared to their total volume, and at a critical size, the microorganisms eating away at the surfaces just eat it all up.
The natural pathways for the degradation and biodegradation of plastics have been know since 2008-09 or so, splashed about in the major journals. This is not secret information.
It does not surprise me that that the NY Times author, Tatiana Schlossberg, does not know this — she is not a science journalist. It does not surprise me that the NY Times environmental desk editor does not know this (or chooses not to know) — the NY Times has long been a bastion of environmental pseudo-science propaganda, and seldom publishes straight science. It does surprise me that Roland Geyer, at UC Santa Barbara’s Bren School of Environmental Science & Management, would say something as foolish as “It accumulates so quickly now and it doesn’t biodegrade, so it just gets added to what’s already there.” — this is his specialty.
It is a Scientific Urban Legend that “plastics are forever”. Most plastics both degrade and biodegrade in the environment — whether in the oceans or in landfills.
Some plastics — such as PVC — resist degradation and thus are useful as building materials replacing such things as metals in plumbing and lumber in siding and building.
The “floating rafts of plastic garbage”-version of the Great Pacific Garbage Patch is a pernicious myth that needs to be dispelled at every opportunity.
The “missing 99% of the plastic in the oceans” has been eaten, mostly by bacteria and other microbes. These little critters will continue to eat the plastic and if we reduce the amount of plastic going into the oceans, they may eventually eat it all up. Microbes are also eating up the plastic in landfills — albeit, much more slowly.
Take Home Message:
Kindergarten rules apply at all stages and areas of life:
Pick up after yourself — clean up your own messes:
We need to do all we can to keep every sort of trash, including plastics, contained and disposed of in a responsible manner – this keeps it out of the oceans and the rest of the natural environment.
Plastics are valuable and should be recycled whenever possible into useful and valuable commodities, such as replacements for lumber in decking, shipping pallets, etc.
Volunteerism to clean up beaches and reefs is effective and worthwhile.
Responsible outdoor recreation, including boating, includes keeping your trash (and especially plastics) under control and disposed of properly ashore.
Tell the truth — it is always better in the long run.
The modern mass media’s abandonment of journalistic ethics is disturbing and dangerous for our society. The replacement of news with propaganda promoting “correct thinking” threatens to turn us into a society of ignorant, mis-educated and misinformed citizens. We all need to do our part to correctly and truthfully portray important issues.
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Author’s Comment Policy:
I’ll be happy to answer your questions and give more references if anyone wants them. I have worked on this issue off-and-on for the last year to satisfy my own curiosity and I find the work of Nature to be truly fascinating.
All this said, plastics need to be recycled or disposed of properly, like all other trash — just because it’s the right thing to do.
Thank you for reading here.
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