Authors: Susan Freinkel
Plastic debris may also be exacerbating the fragile state of species that are endangered for other reasons. The population of playful monk seals in the northern Hawaiian islands, already down to twelve hundred, is dwindling even faster because of the dangerous ghost nets that entangle and drown them. Leatherback turtles, a species that survived the extinction of the dinosaurs, is now threatened, in part from choking on plastic bags that they mistake for jellyfish; necropsies of dead turtles found since 1968 show one-third had ingested plastic bags.
Endangered humpback whales that migrate between Antarctica and tropical waters to the north have been repeatedly spotted towing tangles of rope and other debris.
British biologist David Barnes fears that plastic debris may wreak even broader havoc by contributing to the spread of invasive species.
Organisms can easily hitch a ride on a drifting net or cigarette lighterâand such objects may be even more effective vehicles for transporting species around the planet than ship hulls or ballast water, he said. There's more debris than ships in the oceans, and it travels everywhere, reaching places never visited by boats, such as the far-flung Antarctic Ocean islands, where the same flora and fauna have existed for eons, untouched by the rest of the world's restless mingling. When researchers stepped ashore on the aptly named Inaccessible Island, a tiny volcanic upthrow deep in the Antarctic Ocean, Barnes said they found fishing buoys, plastic bottles, and disposable lighters, any of which could be harboring unwelcome 'migr's. The first new species to arrive in such a place could have a massive impact on the system. "Plastic is not just an aesthetic problem," he said. "It can actually change entire ecosystems."
But there also are organisms that may be benefiting from the ever-growing flotilla of plastic, underscoring the complexities of how the natural world is coping with the synthetic assault. The oceans are filled with microorganismsâdiatoms, bacteria, and planktonâcontinually searching for surfaces to glom on to. For them, plastic debris may be an incredible windfallâa veritable shower of FEMA trailers, according to David Karl, a University of Hawaii researcher. Karl's research crew was the one that found the Hong Kong lighter floating in the gyre. The lighter, like every other piece of plastic debris they hauled up in their nets, was coated with a fine slime of microbes, including bacteria and phytoplanktonâorganisms that are essential to the health of the ocean. To his surprise, Karl found that the plants attached to such plastic objects are copious producers of oxygen, churning out even more from their polymer platforms than is normally produced in open ocean. The finding suggests that, at some level, the multitude of plastic debris may be "improving the efficiency of the ocean to harvest and scavenge nutrients and produce food and oxygen," said Karl. Though given all the harm plastics cause, he was careful to say that he was not advocating more plastic in the ocean.
For all the dangers posed by floating bags, castaway lighters, and abandoned nets, the most profound and insidious threat may well be the trillions upon trillions of tiny pieces of plastic speckled across the world's beaches and scattered through its oceans. These itsy bits, collectively known as microdebris, were scarcely on experts' radar until recently. (The first conference devoted to microdebris was held in 2008.) But now they're what many researchers are most concerned about.
For one thing, their presence is increasing, say scientists who have been tracking marine debris over the decades. Microdebris has been accumulating on beaches around the world, even in remote nonindustrialized spots such as Tonga and Fiji. On my trip to Kehoe Beach, I was surprised to see that the sand was suffused with tiny pink, blue, yellow, and white shards of who knows what, as well as the smooth opaque beads that I recognized as preproduction pellets. How had industrial pellets gotten onto this rural beach? They might have leaked out of a shipping container carrying pellets overseas. But more likely, they came from a plastics-processing plant somewhere in the Bay Area, where they may have spilled from a storage silo or loading dock or railcar delivery area and then been blown or washed into storm drains and finally swept out to sea, only to be thrown back up on the beach.
The rise in microdebris is partly due to rising plastics production, which leads to an increase in pellets that can get into the environment: they're now thought to constitute about 10 percent of all ocean debris.
It's also due to the growing use of teensy plastic beads as scrubbers in household and cosmetic cleaning products and for blasting dirt off ships.
(I recently noticed that there are tiny protective beads affixed to the tips of new pens.) But the main source of microdebris is likely macrodebris: the larger pieces of junked plastic that have been fragmented by the sun and waves. Increasingly, experts fear that these bits are just as dangerous to marine wildlife as the lethal necklaces of packing straps and nylon netting that can choke seals and sharks and even whales.
The poster child for this kind of threat will be nowhere near as charismatic as the Laysan albatross. Instead it might be a lowly invertebrate, like the lugworm, a long reddish-brown creature that burrows in coastal sediment.
That's one of the animals Richard Thompson, a marine ecologist at the University of Plymouth in England, works with. Thompson trained to study minute marine organisms, like diatoms, algae, and plankton, but in the past decade his research has come to focus on the impact of minute marine debris. In one series of lab experiments, he fed micro-sized plastic particles and fibers to three different bottom-feeding creatures: lugworms, barnacles, and sand fleas, all of which eat various types of beach detritus. They all promptly ingested their synthetic meals. Sometimes the particles blocked their intestines, which was fatal. But if the bits were small enough, they passed through the animals' digestive tracts without consequence.
Another researcher did a similar feeding study with mussels: not only did the mussels eat the plastic bits, but forty-eight days later, the bits were still in the mussels' systems.
It's not just bottom dwellers that are ingesting microdebris. In a 2008 return trip to the Pacific gyre, Moore harvested hundreds of lantern fish, small fry that dominate the middle depths of the ocean and rise to the surface at night to feed on plankton and, it now appears, plastic. Moore found that 37 percent of the fish he sampled had plastic in their guts; one had a bellyful of eighty-three plastic bits, a considerable cargo for an animal scarcely two inches long. The fish are a staple in the diet of the tuna, swordfish, and mahi-mahi caught near Hawaii, which in turn are popular in the diet of the next creatures in the food chain: us.
That's particularly disturbing in light of recent findings about what those plastic bits may contain. Japanese researchers have found that pellets and fragments of certain plastics (particularly polyethylene and polypropylene) act as sponges, sopping up toxic chemicals that are widely present in the oceans, including PCB, DDTâtwo carcinogens long banned in the United Statesâand endocrine-disrupting substances such as bisphenol A, fire retardants, and phthalates. Geochemist Hideshige Takada has found that pellets collected from the world's beaches can contain concentrations of chemicals 100,000 to 1,000,000 percent higher than the surrounding water or sediment.
Ironically, that's no surprise to scientists who study ocean contaminants; they've long used plastic beads for just that purpose, to pull toxins out of seawater samples.
Indeed, Takada argues the pellets can be used to monitor the presence of persistent organic pollutants in oceans around the world.
I packed up a hundred and fifty pellets I collected on Kehoe Beach and sent them to Takada for analysis. The report I got back nearly a year later showed that the pellets contained small amounts of pesticides, including DDT, the compound that prompted Rachel Carson's book
Silent Spring
and that has been outlawed for all but limited uses since 1972. The analysis also showed that the pellets had "moderate concentrations" of PCBs (ninety-six nanograms per gram), which, according to Takada, was a much higher level than pellets found in Central America or tropical Asia but lower than those from urban areas such as Boston Harbor, Seal Beach in Los Angeles, and Ocean Beach in San Francisco.
Thompson and other researchers fear that these microplastics represent tiny time bombs that could be getting into the marine food chain and working their way back up the long ladder to us. Though there are still more questions than there are clear-cut answers, the early evidence is worrisome. More than 180 species have been documented to eat plastic debris,
and the small number of studies to date suggests that chemicals absorbed into those plastics can also desorb into the animals' systems and bodies. Thompson placed lugworms in sediment containing contaminated plastics and found that after ten days there was a higher concentration of chemicals in the worms' tissues than in the surrounding mud, suggesting that the chemicals had leached off the microbits and into the worms.
Thompson's colleague Emma Teuten fed sea birds pellets laced with notoriously persistent PCBs and later found traces of the chemical in the birds' tissues and preen glands.
The PCB finding is especially disturbing because once PCBs are ingested, the chemicals migrate to fatty tissues, where they remain.
The consequences of that persistence have been sadly demonstrated in the Arctic ecosystem, where over the course of several decades the chemicals have risen up through the food chain from small fish to big fish to polar bears, seals, and whales, and finally to the Inuit natives, who, owing to a diet rich in the fatty meat of seals and whales and bears, have been found to harbor some of the world's highest levels of PCBs in their blood and in the women's breast milk.
Still, it's complicated to pin down the role polymers play in passing on these toxins that are already so widely present in the environment. For example, University of Connecticut researcher Hans Laufer found alkyphenolsâchemicals used in making plastics and rubberâin the blood, tissues, and shells of lobsters. He suspects the compounds may be responsible for a shell-softening disease that has devastated East Coast lobster populations.
But how did the alkyphenols get into the lobsters? As bottom feeders, the lobsters might have ingested contaminated plastic fragments or smaller organisms that had eaten contaminated bits. Or they may have absorbed the alkyphenols directly from seawater. The ocean, the seabed, and the coastlines in many parts of the world are already polluted with chemicals. The question, said Thompson, is "How much worse do plastics make it?"
Certainly plastics enable the mentality that makes it all too easy for a person to simply discard an object when it is used up with little thought about the consequences. The era of disposability has fundamentally changed our relationship to the things surrounding usâwhether of our own manufacture or nature's. Consider, for instance, the mental and cultural shift involved in adopting something like the disposable lighter.
Disposable lighters were not replacing disposable paper matches only. The tool they were really stepping in for was the refillable pocket lighterâmost famously represented by the Zippo, the inexpensive lighter made of chrome and steel that gained an enduring place in America's heart during World War II, when they were standard issue for every GI. From their debut in 1932 to this day, Zippos come with a lifetime guarantee: "It works or we fix it for free." Over the decades, the Bradford, Pennsylvania, company has repaired nearly eight million.
Although Zippos, like Bics, are mass-produced and made from humble materials, there is a thriving collectibles trade in them; not the case for Bics or other disposables. Collectors like the advertising logos and themed images Zippo has always printed on the sides of its lighters. Bic has done the same; it offers limited-edition lighters each year, which are decorated with NASCAR heroes or sports-team logos or nature-themed pictures of wildlife and trees. Still, collectors have little interest. "We don't really consider they are lighters," said Judith Sanders, a member of a collectors club called On the Lighter Side. Ted Ballard, an Oklahoma lighter lover who used his collection of forty thousand lighters to create the National Lighter Museum, sniffed at the idea of collecting Bics. "It came to a pretty sad world when people would accept a plastic lighter as a thing they'd carry in their pocket," he told me. "There's no esteem to it."
Why do people "esteem" their durable lighters but not the throwaways? Technically speaking, there's not a huge difference between a Bic and a Zippo. Both rely on essentially the same mechanism to make fire: fuel released through a valve and sparked by the turning of a flint wheel. But the fact that a Zippo can be refilled and a Bic cannot bespeaks a world of difference. If you can't reuse or repair an item, do you ever really own it? Do you ever develop the sense of pride and proprietorship that comes from maintaining an object in fine working order?
We invest something of ourselves in our material world, which in turn reflects who we are. In the era of disposability that plastic has helped foster, we have increasingly invested ourselves in objects that have no real meaning in our lives. We think of disposable lighters as conveniencesâwhich they indisputably are; ask any smoker or backyard-barbecue chefâand yet we don't think much about the tradeoffs that that convenience entails.
The convenient disposables that
Life
magazine celebrated in 1955 appeared in the picture to be magically suspended midair; readers didn't see the next frame in the photo shoot, the one that would have shown them piled up on the ground. For decades, humans have accepted the illusion of that first photographâthat convenience comes with no cost or consequence. But now we're recognizing that our plastic throwaways do not simply go away. They go
somewhere,
and, in the worst case, they become matter out of place.
6. Battle of the Bag
I
T'S NOT ALWAYS
easy to see when a relationship is in trouble. People have been known to cut down their forests, exhaust their local water supplies, and deplete their soil, failing to recognize or understand the natural foundation for human existence. Plastics seemed to promise a new foundation for human life: food comes sliced and diced and packaged in plastic; sports are played on grass made of plastic; homes are wrapped in plastic; and every year brings new time-saving devices and electronic miracles encased in plastic.