As environmental sensibilities have begun to
take hold in the U.S., promising forecasts of
a new generation of "green" products made from
"natural" materials often outpace the growth of
stable markets and environmentally sound manufacturing
systems. Federal legislators are now pushing this
approach to environmental responsibility, while
supporting the agriculture industry.
Aiming to increase markets for U.S. agricultural
products and promote their environmental benefits,
the recently enacted U.S. farm bill requires federal
agencies to "…give preference to such items composed
of the highest percentage of bio-based products
practicable…" If this provision does indeed stimulate
federal procurements and new market demands, it
could also provide a valuable opportunity for
industry to explore the promise of bio-based materials
as biological nutrients circulating productively
in the biological metabolism. Without this approach,
the indiscriminate use of bio-based materials
could only offer the illusion of environmental
benefits.
Interest in Bio-Based Materials
Using bio-based materials is nothing new. Industry
has plenty of experience using natural and cellulosic
fibers for textiles, paper, cardboard, and a variety
of wood products. And as sustainability becomes
an integral part of corporate agendas, interest
in bio-based products is growing.
Hopefully new interest will bring a sophisticated
understanding of the life cycle of bio-materials.
Bio-based products are commonly perceived as inherently
ecologically intelligent. Because they are derived
from what is considered a renewable resource,
bio-based materials are often championed for reducing
reliance on scarce mineral resources. Bio-based
polymers, for example, are drawing lots of attention
as an alternative to petroleum-based packaging,
which rapidly turns a valuable resource into waste.
And the biodegradability offered by many biopolymers
seems an attractive alternative to typical solid
waste disposal methods.
Valuing Biological Nutrients
But if bio-based products are to produce real
environmental benefits, they must be specifically
designed so their bio-based materials can be safely
recovered and returned to the soil. That means
that each bio-based ingredient must be fully non-toxic
and biodegradable—what MBDC calls a biological
nutrient—becoming food for healthy and productive
soil.
Products made for complete return to the soil
are Products of Consumption. Other products might
be designed to combine both biological and technical
nutrients (hybrid products). The key in designing
hybrid products is to facilitate the return of
their materials into healthy biological and technical
metabolisms after use. If bio-based products combine
biological and technical nutrients in unrecoverable
ways, the result can be much less ecologically
intelligent than products that don't include bio-based
materials at all.
Composite lumber, made from recycled plastics
and waste wood (chips or sawdust), is one product
that is marketed for its perceived environmental
benefits as well as its performance. The use of
recycled and bio-based materials seems to resonate
in the market. But this is an example of exactly
the kind of 'downcycling' that renders both the
technical nutrients (the plastic) and biological
nutrients (wood) unrecoverable after use. In the
context of Cradle to Cradle Design, it's an unintelligent
use of materials and a last stop on the way to
the landfill or incinerator.
The effective use and recovery of biological
nutrients implies the need for strategic alliances
to coordinate industry-wide, closed loop material
flows. No company—no single industry, even—can
develop this cradle-to-cradle infrastructure alone.
It will require a cultural shift, perhaps encouraged
by incentives from local, state, and federal agencies
to those who wish to construct a new materials
economy using biological nutrients as viable currency.
That said, there is much individual companies
can do. Beginning with an examination of the life
cycles of materials, designers and engineers can
assess the elements of production, design, manufacture,
and recovery that determine the long-term value
of bio-based products.
Safety: Many bio-based materials begin
their life on the farm. Conventional farming practices
are also in need of environmental optimization.
Most fertilizers, pesticides, and herbicides are
petroleum-derived, so the definition of current
agricultural products as renewable isn't
an absolute truth. And conventional farming methods
tend to result in soil erosion and salinization,
aquifer depletion, nutrient loading, and toxic
chemical run-off. These issues clearly affect
the overall ecological profile of biological materials.
Food vs. Materials: Consumers in developed
nations wield incredible influence over the flow
of resources throughout the world. Observing that
the United States in one of the primary exporters
of basic grains and foodstuffs, what are the potential
social implications of using arable lands to grow
industrial materials instead of food? For example,
if we use the edible part of plants to synthesize
carbohydrate-based polymers for convenience food
packaging in the U.S., can we ensure that we are
not unintentionally denying someone else's children
the most basic nutrition? When we talk about sustainability,
we also have to ask for whom.
Bio-Based…Plus What? A bio-based raw material
is a good beginning; but what happens to a potential
biological nutrient in the manufacturing process
is equally important. What kinds of chemicals
are used to process it? What kinds of dyes, pigments,
adhesives, fillers, UV- inhibitors, stabilizers,
plasticizers, bleaching agents, and binders will
be added to the product? These components can
have serious human and ecological health impacts,
perhaps especially in biodegradable materials
that can release their chemical constituents more
readily than longer-lived petroleum plastics.
Given the potential for direct interaction with
ecological systems after product use, bio-based
products should be manufactured with an added
measure of care.
Recovering Nutrients—To Reuse or to Compost?
Developing closed-loop systems for recovering
and re-utilizing bio-based materials is necessary
for maximizing their value as nutrients. But some
bio-based materials designed as nutrients have
the potential to be productive in either technical
or biological metabolisms. Durable products might
be especially well suited the technical metabolism;
more transient products for the biological metabolism.
For a bio-based product designed to be even moderately
durable, why take all of its inherent quality
and return it to soil after its first product
life is over? Why not preserve its quality by
anticipating future product designs? For example,
agricultural fibers with a non-toxic binder used
to manufacture automotive door panel carriers
could be collected, shredded, and pressed into
new carrier panels. If no opportunity exists for
refurbishing the material, it could be sold and
used for products in other industries without
impeding its potential to ultimately return safely
to soil.
The greatest potential value for rapidly renewable
and biodegradable materials may exist for those
products that have very brief terms of use. For
single-use or short duration products, it may
be most appropriate to recover their value as
compost.
Value Recovery Opportunities
The opportunities offered by capturing the value
of the massive amounts of organic wastes generated
by every household in the industrialized world
are immense. Given the volume of this "waste"
stream, and the persistent, worldwide loss of
topsoil, it makes good sense to create materials
that can safely biodegrade. Products such as these
give businesses and communities the opportunity
to turn liabilities into revenue-trash and disposal
costs can be converted to productive biological
nutrients.
There is perhaps no better reason to carefully
explore the value of bio-based materials.
Find Out More:
 |
Read Title IX of the 2002
Farm Bill, containing the bio-based materials
procurement requirements. |
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