Is it better to create packaging from renewable resources than from nonrenewable sources? Packaging derived from renewable
resources such as trees and other plants slows the depletion of nonrenewable resources such as oil, steel, and aluminum. However,
making packaging from food plants such as corn is not a sustainable practice if it reduces the food available for people or
increases its cost.
In defense of PVC
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In addition, although the recycling infrastructure for fiber-based packaging such as paper and corrugated boxes is well established
and those materials are recycled at a relatively high rate, recycling for biopolymers is virtually nonexistent. Even worse,
the presence of biopolymers may contaminate the recycling stream of conventional polymers. Polylactide, for example, ruins
recycled polyethylene terephthalate (RPET) at levels of less than one bottle per thousand, according to a study by PTI-Europe
(Yverdon-les-Bains, Switzerland) for the Technical Committee of Petcore.
However, it may be possible to obtain traditional polymers from renewable resources, which would be the best of both worlds.
A joint venture is building a facility in Brazil to produce linear-low-density polyethylene from sugarcane-derived ethanol.
The resulting resin, scheduled to be available in 2011, will be molecularly and functionally equivalent to traditional hydrocarbon-based
linear-low-density polyethylene (Dow Chemical, Midland, MI, and Crystalsev, São Paulo, Brazil).
Hybrid resins that combine petroleum content with renewable content also are appearing on the market. One polypropylene made
of equal amounts of petroleum and starch injection molds, extrusion blowmolds, and thermoforms just like purely petroleum-based
resin (Biopropylene, Cereplast, Hawthorne, CA).
Are biodegradable materials better than nonbiodegradable materials? Not if they end up in a landfill. Modern landfills are
designed to prevent decomposition. Thus, "biodegradable material in a landfill is of questionable value," says Enneking. Even
worse, biomaterials that do degrade generate methane, a GHG with 23 times more heat-trapping power than carbon dioxide. According
to the Environmental Paper Network, more than one-third of municipal solid waste is paper, and municipal landfills represent
the largest source of human-related methane emissions. In fact, the US Environmental Protection Agency has identified the
decomposition of paper as among the most significant sources of landfill methane.
Are compostable materials better than biodegradable materials? Compostable materials are biodegradable, but not all biodegradable
materials are compostable. Compostable materials decompose in commercial or home composting facilities in a matter of weeks
without any negative impact. To ensure compostable packaging performs as expected, it should meet US or European standards
for degradability in industrial composting settings (i.e., ASTM D6400 or EN 13432, respectively) or be certified by the Biodegradable
Products Institute. Yet the extremely limited access to commercial or home composting facilities means that few compostable
packages are actually being composted at present.
Is packaging that contains recycled content better than that made of virgin material? Recycled content will significantly
reduce costs and GHG emissions for packages made of aluminum, glass, and steel. In addition, these materials can be recycled
repeatedly with no loss in properties.
Infinite reuse of fiber- and polymer-based packaging may not be possible, however, because each generation tends to suffer
a loss of properties. Still, technology continues to improve the properties of these recycled materials. As it does with aluminum,
glass, and steel, recycled content in fiber-based and polymer packaging reduces energy consumption and GHG emissions. High
percentages of recycled content are possible, too. Packaging with 100% recycled fiber content is commonplace and often marked
with a special logo (100% Recycled Paperboard Alliance). Percentages of recycled polymers tend to be lower. But food-grade
containers made of 100% RPET, a percentage once thought to be impossible, are on the market.
Food-grade PET film with recycled content is available for use in thermoformed trays, clamshells, surface-sealed blisters,
and other containers. Some films not only offer guaranteed levels of recycled content but also are produced with renewable
energy ("SmartCycle" films, Klöckner Pentaplast).
Hurdles to sustainable packaging
Recycling rates for most packaging materials are low in the US, compared with many other parts of the world. Rates range from
about 20% for glass containers to 78% for corrugated boxes (see Table I). To raise recycling rates, collection rates must
increase. Increasing collection rates would entail convincing business, government leaders, and consumers to view used packaging
as a raw material rather than waste, improving the reach and efficiency of the collection infrastructure, and advancing sorting
technology to increase the purity of sorted material streams. It's also necessary to address economic factors to ensure that
collection programs generate income, or at least break even, rather than drain community resources. A particularly important
goal should be to change consumer behavior to eliminate the reasons for not recycling such as laziness, inability or unwillingness
to pay fees for curbside collection of recyclables, absence of curbside collection or convenient drop-off programs, and lack
of collection points.
Hallie Forcinio is Pharmaceutical Technology's Packaging Forum editor, 4708 Morningside Drive, Cleveland, OH 44109, tel. 216.351.5824, fax 216.351.5684, editorhal@cs.com
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