Protecting the Land
BIO. "Protecting Our Environment" Washington, D.C.:
Biotechnology Industry Organization, 1992.
Protecting Our Farmland
In agriculture, applied biotechnology allows farmers to dramatically
reduce the volume of chemicals they introduce into the
environment. Traditional agriculture requires millions of pounds of
herbicides, insecticides, and fertilizers to foster and protect food
and fiber crops. Some of those chemicals can remain in the soil.
Some seep into groundwater. Some are toxic to people, wildlife, and
beneficial insects. Some even retard crops farmers want to protect.
Biotechnologists are changing that. They are modifying and
strengthening plants' natural defense systems and developing natural
biopesticides. And in the process, they are making the environment
safer for the farmer, his family, and the rest of the world.
Natural biopesticides are another development of biotechnology that
help farmers reduce chemical use. They degrade rapidly, leave no
residues, and are toxic only to target insects.
One strain of bacteria, for example, Bacillus thuringiensis (B.t.),
produces a protein that is naturally toxic to certain insects.
Scientists have extracted the B.t. gene that expresses the
insecticide and inserted it into common bacteria that can be "grown"
in large quantities by the same fermentation techniques used to
produce such everyday products as beer and antibiotics. Spread on
cotton and other crops, these harmless bacteria control insects
A refinement of this technology even eliminates the bacteria. The
insecticidal substance itself is extracted from the bacteria,
encapsulated, and used to protect a range of crops. No chemicals, no
bacteria, no insect damage.
Spiders, too, provide the gene for a natural insecticide. The
spider's venom-producing gene has been transplanted into a virus that
infects certain crop-destroying caterpillars. When the caterpillar
swallows the virus and becomes infected, the infected cells poison
themselves and the caterpillar. Both the virus and the spider gene
are harmless to plants and animals.
Insect Virus Products, or IVPs, are still another environmentally
beneficial innovation made possible by biotechnology. IVPs were
discovered in nature almost 200 years ago, but only now, using the
techniques of biotechnology, can they be produced economically. All
IVPs are non-toxic to people, animals, and other beneficial insects.
In fact, each specific IVP affects only one type of insect. Yet over
1,600 different insects - many of them important agricultural pests -
are known to be susceptible to IVPs.
As more insect-specific biopesticides emerge from this developing
technology, farmers will be able to treat only the particular insects
damaging their fields, and only when those insects are actually
present. And it can be done without applying broad-spectrum
Cleaning Up Wastes
The use of biotechnology to solve environmental problems, according to
William K. Reilly, former head of the Environmental Protection
Agency, "could be - should be - an environmental breakthrough of
staggering positive dimensions."
Everything under the sun degrades, or breaks down, into different
materials. Fallen leaves become compost, iron rusts, milk turns sour,
and food 'goes bad.' Just as light, heat, and moisture can degrade
many materials, biotechnology relies on naturally occurring, living
bacteria to perform a similar function. Some bacteria naturally
'feed' on chemicals and other wastes, including some hazardous
materials. They consume those materials, digest them, and excrete
harmless substances in their place.
For decades now, municipalities have used biological methods to treat
their sewage, and industry has used secondary aerobic treatment to
remove harmful materials from liquid wastes. Biological treatment is
not a new idea. What is new is the expanded range of biotreatment
capabilities offered by the science of biotechnology.
Bioremediation uses natural as well as recombinant microorganisms to
break down toxic and hazardous substances already present in the
environment. Biotreatment is a broader term, which refers to all
biological treatment processes, including bioremediation.
Biotreatment can be used to detoxify process waste streams at the
source - before they contaminate the environment - rather than at the
point of disposal. This approach involves carefully selecting
organisms, known as biocatalysts, which are enzymes that degrade
specific compounds, and define the conditions that accelerate the
Living Off a Landfill
Vast numbers of bacteria exist naturally in the prevailing conditions
in landfills and other solid waste sites. Some of those bacteria
consume, or degrade, different types of waste present at the site.
But they do it slowly.
Scientists today can examine a landfill and determine not only what
bacteria are degrading which materials in it - including any hazardous
materials - but which do it fastest, most completely, and under what
Armed with this knowledge, they can clone the most efficient strains
of naturally occurring bacteria, reproduce them in quantity, and apply
them to the site. In effect, they can create a customized army of
Oil for Dinner
Some bacteria literally 'live on oil,' just as some people live on
meat and potatoes. And they consume it with just as much relish.
Following the major oil spill in Alaska's Prince William Sound, the
Environmental Protection Agency brought in natural oil-eating bacteria
to help clean up the mess. Follow-up studies suggest that the
microbes did as good a job in cleaning up soiled beaches as
high-pressure hoses and detergents could have done. "It was almost as
if we had brought in fresh rock," stated the EPA's project manager
after visiting the site.
Such bioremediation cannot only help to clean up oil spills, but also
chlorinated chemicals and leaks from storage tanks.
Using naturally occurring bacteria for environmental purposes is a
relatively simple procedure of identification, cloning, and mass
Biotechnologists using recombinant DNA technology - the principal tool
of genetic engineering - can recombine, or mix-and-match, the most
desirable traits of several bacterial species. They can, for
instance, extract the gene from one strain that allows it to 'feed' on
PCBs or other hazardous wastes, then take the genes that allow another
bacterial strain to withstand wide temperature ranges - lack of oxygen
or other environmental extremes - and transplant them into a common,
harmless bacterium that can be mass produced easily. The result is an
organism custom-made to 'eat up' a specific problem waste at a
specific site under specific conditions.
This technology holds the potential to solve many environmental
problems from the past, and leave our children an environment cleaner
than we inherited from our parents.
Of equal, or perhaps even greater importance, biotechnology can
eliminate hazardous pollutants at their source before they enter the
environment. Every year, some 5 billion pounds of 320 potentially
harmful chemicals are released into the environment. The EPA has
targeted 17 of those chemicals for massive reductions. Biotreatment
with naturally occurring biocatalysts has been demonstrated to almost
completely eliminate one of these chemicals, methylene chloride, a
suspected carcinogen, from industrial process streams. About 130
million pounds of this compound are currently discharged each year in
manufacturing process wastes.
Special bacteria in a bioreactor can virtually eliminate methylene
chloride from industrial waste water. They reduce concentrations from
over 1,000,000 parts per billion to less than 5 parts per billion -
far below the EPA's permissible guidelines. The bacteria in the
bioreactor consume the chemical and convert it to water, carbon
dioxide, and salt. They permanently destroy the hazardous material
and eliminate any need to recover it, transfer it, or dispose of it.
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