| Dear
EarthTalk: What is “kenaf” paper?
From what I‘ve heard, it’s good for the environment.
But what exactly are its benefits and where can I obtain
some?
-- Tiffany Mikamo, via e-mail
| |
U.S.
Department of Agriculture research shows that kenaf
yields some six to 10 tons of dry fiber per acre per
year, which is three to five times more than the yield
of Southern Pine trees, now the dominant paper pulp
source in the U.S. Kenaf also absorbs more carbon
dioxide than any other plant or tree. Pictured: Bill
Loftus tends kenaf plants at the Kenaf Research Farm.
© Kenaf Research Farm |
Kenaf,
a fast-growing, non-invasive annual hibiscus plant related
to cotton, okra and hemp, makes ideal paper fiber as well
as great source material for burlap, clothing, canvas, particleboard
and rope. Its primary use around the world today is for
animal forage, but humans enjoy its high-protein seed oil
to add a nutritious and flavorful kick to a wide range of
foods. In fact, kenaf has been grown for centuries in Africa,
China and elsewhere for these and other purposes, but environmentalists
see its future in replacing slower-growing trees as our
primary source for paper.
U.S.
Department of Agriculture (USDA) research shows that kenaf
yields some six to 10 tons of dry fiber per acre per year,
which is three to five times more than the yield of Southern
Pine trees—now the dominant paper pulp source in the
U.S. And to top it off, researchers believe kenaf absorbs
more carbon dioxide—the chief “greenhouse gas”
behind global warming—than any other plant or tree
growing. Some 45 percent of dry kenaf is carbon pulled down
from the atmosphere via photosynthesis.
No
wonder environmentalists are so bullish on kenaf for our
common future. “The more kenaf we grow, we can not
only absorb significant amounts of the carbon dioxide that
is responsible for global warming,” says Bill Loftus
of the non-profit Kenaf Research Farm, “but also educate
the world on how to be self-sustainable through kenaf’s
many properties of providing food, shelter and economic
opportunities.”
As
to its use for paper, 10 major U.S. newspapers have tested
kenaf-based newsprint and were pleasantly surprised by how
well it held up and how crisply it displayed text and pictures.
And since it is already brighter than wood-based pulp, it
requires less bleaching before it can be used to carry ink.
But since kenaf is not mass-produced the way paper trees
are on big plantations across the Southeast and West, it
still costs more than regular paper and as such has not
gone mass market, despite its environmental.
Also,
while some policymakers and many environmentalists would
like to see our paper feedstock switched from Southern Pine
and other trees to kenaf, entrenched timber companies with
big investments in tree farms (and who employ many a Washington
lobbyist) do not. And with many timber companies already
suffering economically,
lawmakers are unlikely to mandate changes that could make
matters worse.
Even
if kenaf doesn‘t become the paper of tomorrow, it
may still have a bright future. The Kenaf Research Farm
reports that Toyota is already using kenaf grown in Malaysia
for insulation and interiors in some cars. Toyota is also
experimenting with using kenaf to reinforce the sugarcane-
and maize-based biopolymers it hopes can replace many of
the plastic and metal parts in the vehicles it is designing
today.
Your
best bet for finding some kenaf paper is to try a specialty
art supply or stationery store. One good online source is
The Natural Abode. Photographers might try using kenaf photo
paper, such as Pictorico’s ART Kenaf, in their ink
jet printers to give their snaps a unique look and a green
pedigree.
CONTACTS:
USDA; Kenaf
Research Farm; The
Natural Abode; Pictorico
ART Kenaf.
Dear
EarthTalk: OK, so are cell phones emitting
dangerous radiation or not? If so, which phones are safer
that others and what do we do to minimize exposure?
-- Luke Alderman, Santa Fe, NM
| |
The
jury is still out as to whether or not the radiation
emitted by cell phones is dangerous, but some manufacturers
are working to reduce the radiation emissions of the
phones they make. Though it may make you look bionic,
a safe bet is to use a headset or ear piece to create
distance between the phone and your head when calling.
© Thinkstock |
The jury is still
out as to whether or not the radiation emitted by cell phones
can cause negative health effects for callers. Mobile phones
emit signals to communicate with cellular towers via radio
waves, which are comprised of radio-frequency (RF) energy,
a form of electromagnetic radiation.
The U.S. Federal
Communications Commission (FCC) limits the amount of radiation
any phone sold in the U.S. can emit to what it considers
a safe level of 1.6 watts per kilogram of body weight (a
measure of the energy absorbed by the body when using a
wireless device). But some health practitioners are concerned
that even this level of exposure may be too high, resulting
in people unwittingly exposing themselves to potentially
harmful radiation every time they make or take a call.
Such radiation
is known to heat up living tissue it comes into close contact
with by a fraction of a degree, but this level of temperature
increase is less than that caused by exposure to direct
sunlight, and the brain’s blood circulation typically
disperses this excess heat quickly by increasing local blood
flow.
Some recent studies
have found higher risks for brain and salivary gland tumors
among people using cell phones for 10 years or longer, while
other research has found little if any risk. Other research
has looked at the reproductive, cognitive and sleep effects
of RF energy at levels similar to what cell/smart phones
emit. Results have been mixed. More studies are now underway
to resolve whether or not cell phones are safe for people
to use, but some electronics manufacturers aren’t
waiting around to cut down on the radiation emissions of
the phones they make and sell.
If you are in
the market for a new cell phone, check out the nonprofit
Environmental Working Group’s (EWG’s) rundown
on which of the thousand or so popular cell/smart phone
models give off the most and least radiation. Levels vary
widely, from as little as 0.3 to the legal limit of 1.6
watts per kilogram of body weight. Sanyo’s Katana
II, Samsung’s Rugby, Nokia’s 7710, and the Blackberry
Storm, among others, get top marks from EWG for giving off
lower amounts of radiation (in the 0.3 range). Meanwhile,
more than a dozen different cell/smart phones (including
some of the most popular models such as Motorola’s
Droid, Blackberry’s Bold 9700, LG’s Chocolate
Touch and HTC’s Nexus One by Google) are categorized
as “worst” by EWG for giving off larger amounts
of radiation (pushing the 1.6 limit). Apple’s iPhone
3Gs is in the middle of the spectrum, leaking between 0.52
and 1.19, depending on usage.
Regardless of
which cell/smart phone you use, you can minimize your exposure
to RF radiation by taking a few simple precautions. For
one, using a headset (these give off significantly less
radiation) or speaker phone keeps the phone itself away
from your head. Also, your phone emits far less radiation
when used to text instead of call—and the phone isn’t
next to your brain when texting—so the more you tap
(just not while driving, please!) instead of talk the better.
Also, a poor signal (fewer bars) means that your phone has
to work harder—and emit more radiation—to connect
up to a wireless tower, so wait to make that call until
you are somewhere with a stronger connection.
CONTACTS:
FCC;
Environmental Working Group. |
