Plastic (31 page)

There's no mystery why. A century into mankind's love affair with plastic, we're starting to recognize this is not a healthy relationship. Sure, plastics have been a good provider, but that beneficence comes with many costs that we never even considered in our initial infatuation. Plastics draw on finite fossil fuels. They persist in the environment. They're suffused with harmful chemicals. They're accumulating in landfills. They're not being adequately recycled. In short, they exemplify shortsighted thinking about the long-term impacts of manufactured materials and represent an unsustainable wasting of resources. Environmentalists have been making that case for years. Now even the plastics industry is coming to the same conclusion. As a Dow executive told
Business Week,
"Our whole industry agrees that plastics have to be more sustainable."

In any event, it's not as if we can get a divorce. Plastics are one of the material foundations of modern life, and in many contexts, that's a good thing. We want our solar panels, bike helmets, pacemakers, bulletproof vests, fuel-efficient cars and airplanes, and, yes, even much of our plastic packaging. As they did in the late nineteenth century, plastics have a vital role to play in a world of dwindling natural resources. And that will be even truer in coming decades as we grapple with climate change. More and more of our decisions about how to build our homes, transport ourselves, and package our stuff will be driven by carbon calculations. By that measure, lightweight, energy-efficient plastics can offer extraordinary opportunities.

But to live in harmony with plastics, we have to change the terms of the relationship. We need to develop plastics that are safer for people and the planet, and we need to deploy them more responsibly. And that means change on the parts of all residents of Plasticville: the producers of plastic things, such as credit cards, and the consumers who use them.

What constitutes a green plastic? Though there's plenty of debate, most would agree that one starting place is the use of renewable raw materials, a quest that, ironically, takes the industry full circle, back to plastic's earliest roots as a material derived from plants. Remember celluloid? That wasn't the only plant-based polymer. Throughout the early decades of the twentieth century, there was widespread interest in making other types of plastics from agricultural crops, such as corn or legumes or soybeans. Indeed, agricultural interests competed fiercely with the nascent petrochemical industry to capture the market on polymers.

Henry Ford, who was eager to find industrial uses for surplus crops, put his money on soybeans. He often claimed it would be possible to grow most of an automobile. To that end, he planted thousands of acres of soybeans and converted one of his plants at River Rouge to the production of a soy-based plastic. The typical 1936 Ford had ten to fifteen pounds of soy plastic in its steering wheel, gearshift knob, window frame, and other parts. In 1940, Ford famously invited reporters to see a "farm-grown" car. Ever the showman, the septuagenarian hefted an ax and swung it hard against the back of the custom-built car. Instead of crumpling, the panels bounced back into shape. Or, as a reporter for
Time
magazine put it, "the fenders of the Buck Rogers material ... withdraw from collisions ... like unhurried rubber balls."

But Ford didn't get a chance to make more than one plastic car before World War II broke out. Then even he couldn't buck the advantages petrochemistry had to offer. Oil was inexpensive and plentiful, and unlike soybeans and other crops, it didn't depend on growing seasons. What's more, the plastics made from fossil fuels were more waterproof and versatile than those made from soy.
Only a few plant-based polymers survived that contest with petrochemistry, among them cellophane, celluloid, and the textiles rayon and viscose.

Now, with the era of cheap fossil fuels coming to an end, the petro-based resin manufacturers are combing the natural world for new building blocks. They're looking at agricultural crops, such as corn, sugar cane, sugar beets, rice, and potatoes. And they're exploring historically undomesticated sources of carbon, such as switchgrass, trees, and algae. "Carbon is carbon. It doesn't matter if it was sequestered in an oilfield 100 million years ago or six months ago in an Iowa cornfield," as one bioplastics executive put it.
As it turns out, that's not entirely true.

Much of the current effort amounts to pouring new feedstocks into old bottles, using plants to make conventional polymers of all sorts. Brazil's petrochemical giant Braskem, for instance, is building a 450-million-pound-capacity plant to make sugar-cane-based polyethylene, the same material Coca-Cola is deploying in its PlantBottle.
(To publicize the venture, Braskem teamed up with a toy maker to produce the game pieces for a Brazilian version of Monopoly, which they called Sustainable Monopoly—perhaps appealing to the capitalist's inner environmentalist, or vice versa.
) Sugar-cane ethanol already fuels most cars in Brazil, and the country is hoping its vast cane plantations will allow it to become a global hub for cane-based plastics as well.
Dow Chemical has grabbed the hook, teaming up with local ethanol producer Crystalsev to build its own cane-based-plastics plant in Brazil.

Likewise, various resin companies have worked out ways to make polypropylene and PET from sugar, nylon from beets, and polyurethane from soy. That last has given Ford a chance to fulfill its founder's dream: the company has used soy-based polyurethane cushions and padding in more than 1.5 million cars and eventually plans to make all the plastic parts in its cars from various types of compostable plant-based plastics.
Meanwhile, Solvay, one of the world's largest producers of vinyl, is exploring plant sources for the ethylene used in making PVC.

These bioplastics may or may not be an improvement on their fossil-fuel-based relatives. Certainly they have a far lower carbon footprint, by virtue of their renewable feedstocks. Some are, in principle, recyclable, and many are compostable. Yet there's no guarantee they are manufactured with less harmful chemicals or contain any fewer worrisome additives. A credit card made of a plant-based PVC, for instance, would still contain toxic vinyl chloride. "Just because it's biobased doesn't make it green," pointed out Mark Rossi, a Boston-based activist and researcher who has spent much of his career thinking about how we can forge a healthier relationship with plastics.
For years that was a fairly lonely pursuit. But lately, he's found he has a lot of company. "I was on the plane coming back from Chicago or Detroit or somewhere," he recalled when we met for coffee. "I was talking to this woman I was seated next to who was a mom. And she was totally up on all this stuff, like bisphenol A-free bottles. Five years ago it wasn't on most people's radar."

Rossi got interested in polymers in the late 1980s, during the hue and cry over the country's solid-waste crisis. That was back when McDonald's was under attack for selling their burgers in Styrofoam clamshells, he recalled, and the company proposed putting "little Mc-incinerators" in their stores to get rid of the waste. "This was their solution," he said with a slight chuckle, still struck, after all these years, by its absurdity. The controversy prompted the subject of his master's thesis in environmental science: a life-cycle assessment of polystyrene packaging. He went on to work on an influential 1992 study that to everyone's surprise—including his own—showed that plastic packaging wasn't the thorough environmental villain often supposed. The study found that some of the most significant environmental impacts of packaging are a consequence of weight. Plastics permit smaller and lighter packages, which require less energy and resources to produce than glass or paper or other materials. From there Rossi moved on to examining the problems of chemical additives, eventually working with Health Care Without Harm on their campaign to get PVC out of hospitals. Now he's research director of Clean Production Action, a group that works with businesses and government to push for the use of safe chemicals and sustainable materials in manufacturing.

Those efforts have taught Rossi a few things. One is that "all plastics aren't created equal." Some are greener, or have the capacity to be greener, than others. That's as true of biopolymers as it is of petro-based plastics. As Rossi learned, there are decisions made at every stage of a plastic's life cycle that determine its health and environmental impacts—from choice of feedstock and how it is processed or grown, to the ways in which the polymer is manufactured and processed, to how the product is used, to the available options at the end of its useful life.

With that framework in mind, Rossi has helped develop two different scorecards for assessing plastics—one aimed at plastics in general, and another specifically for biobased polymers.
Still works in progress, the scorecards are designed to help manufacturers, buyers for stores, and government agencies evaluate the environmental qualities of the plastic resins and products they are buying. A beverage company, for instance, could use the scorecard when weighing whether to bottle its water in a corn-based plastic or a polyethylene made from sugar cane. Or a buyer for a big-box store could use the scorecards to decide between a product that's packaged in polypropylene and one in PVC.

Each of the scorecards drills down into the nitty-gritty of plastics production, addressing questions such as: What crops were used in a bioplastic and how were they raised? What types of catalysts were employed to create a given polymer? What additives does it contain? What chemicals might be released in recycling? Is it being deployed in single-use products? How much recycled content does the plastic contain? The scorecards aren't life-cycle analyses—those tend to focus on the energy expended in making a product and aren't very effective at assessing issues such as the chemical impact. Rather, they provide an exercise in what Rossi calls "life-cycle thinking."

Sometimes life-cycle thinking delivers surprising answers. For instance, a plastic doesn't have to be biobased to start looking green. It's possible to make polypropylene without a lot of hazardous chemicals, and a polypropylene package that also contains high levels of recycled content could actually rate higher than a plant-based plastic. Likewise, a plant-based polymer can fall in its rating if the crops used to make it were genetically modified or sprayed with pesticides, or if harmful chemicals were used in its production. And some plastics, notably PVC, are intrinsically problematic. Even a biobased PVC would likely flunk due to the chlorine in the polymer chain that generates troublesome ripple effects across the life of the plastic.

At this point, it's tough for any plastic to earn straight As, acknowledged Tim Greiner, who worked with Rossi on the basic-plastics scorecard. He and Rossi intentionally set the bar high to try to spur the design of better plastics and plastic products. They're calling on industry to start doing the kind of life-cycle thinking about plastics that wasn't done decades ago when these dazzling new materials first burst onto the scene. "We wanted to define the true north, the direction [the industry needs to go] and give people the compass," said Greiner.

Some might say true north lies in a cornfield in Blair, Nebraska, site of NatureWorks, the world's largest producer of a wholly new kind of plastic derived from plants. NatureWorks makes a corn-based polymer called polylactic acid, or PLA.
Chances are you've already encountered this plastic via its trademarked name, Ingeo. It's now in thousands of packages and consumer goods, including the "corntainers" Walmart uses to package fruits and veggies, the floor mats in Toyota Priuses, the casings of computers made by Fujitsu and NEC, the bottles used by Newman's Own salad dressings, the bottles of several brands of bottled water, the soda cups distributed by KFC, as well as gift cards issued by a number of retailers, like my daughter's Apple iTunes card. Gift cards and credit cards are potentially a huge market, said NatureWorks spokesman Steve Davies, adding that the card market is being driven by the card issuers rather than NatureWorks. "Everyone wants to get away from PVC," he explained. Visa and MasterCard have approved the use of Ingeo in credit cards, he said, and now "it's up to banks to adopt it." (Making the change can be tricky, as snack giant Frito-Lay learned. The company proudly announced that it was using PLA for the packaging of its SunChips, but less than a year later it switched back to conventional plastic because consumers had complained that the new bags were too noisy. The crackling sounds the bags made were louder than "the cockpit of my jet," groused an air force pilot in a video blog headlined "Potato Chip Technology That Destroys Your Hearing." He ran sound tests and claimed the bags registered 95 decibels, which is in the same range as a backhoe or lawn mower. "You feel guilty about complaining, since they are doing a good thing for the environment," another consumer told the
Wall Street Journal
. "But you want to snack quietly and you don't want everyone in the house to know you are eating chips.")

The building block of PLA is lactic acid, a natural compound that NatureWorks derives from the sugar in cornstarch. You don't have to use corn to make lactic acid; any starchy plant will do, including sugar beets, wheat, rice, or potatoes. The world's other major producer of PLA, Purac, has its main plant in Thailand and uses tapioca or sugar cane for feedstock. But NatureWorks is partly owned by Cargill, the world's largest purveyor of corn, hence the company's first factory was built on corn. Literally. The plant sits amid Cargill-owned cornfields. But Davies insisted the company is agnostic about potential feedstocks and plans to use whatever crop makes the most sense when it builds plants in other parts of the world.

Whatever the source, the lactic acid is converted to a monomer called lactide. Those molecules are then strung together into the polymer PLA. PLA is a fairly versatile plastic, able to perform many of the same functions of existing petro-plastics and capable of being processed with the same types of equipment. Like PET, it can be molded into clear, stiff shapes that are great for packaging. Like polypropylene, it can be extruded into the nonwoven fabric used in diapers and wipes, and like nylon and polyester, it can be spun into fibers for carpet and clothing. Among its shortcomings, however, is a melting temperature low enough that PLA bottles have been known to deform when left too long in hot cars.
And it can't hold in carbon dioxide the way PET can, making it ill suited for the vast soda bottle market.