The Best Bug Repellent?
Mark’s Daily Apple
by Mark Sisson: 10
Foods I Couldn’t Live Without
unofficial but infamous season this time of year in New England
(my native homeland, for those of you who don’t know). In the weeks
roughly between Mother’s Day and Father’s Day is a period the locals
call black fly season. For those of you unfamiliar with these creatures,
there’s no overdramatizing their menace. They’re deceptively minuscule
but ubiquitous, and their bites can mutilate. I remember a couple
from the Midwest moved to our neighborhood just before the school
year. Come spring, they’d heard the many jokes and well-intentioned
warnings but scoffed when they first saw the flies themselves. “Those
gnats?” they asked incredulously. About a week or so later they
were both covered in welts after spending the weekend doing yard
work with no protection. The woman’s hairline was chewed to oblivion.
(These things tended to get around the neighborhood.) I still think
of black fly season after all these years especially when I get
questions from readers about bug season in their parts of the country.
Increasingly, folks ask about a Primal alternative to chemical
behind bug repellents, of course, is to repel. Whether chemically
or naturally-derived, a repellent’s job is to make you as unappealing
to bugs as possible. And, yes, some people are more enticing. Mosquitos,
example, target their blood donors (actually it’s the blood
proteins they’re after) by their smell in addition to lactic acid
(mmm…human sweat) and carbon dioxide output. The respiration
part explains why the little ones (and pregnant women) tend to get
eaten alive out there while others in your party escape with nary
a bite. Using genetically modified insects, researchers have also
found that taste
plays a part as well as smell for mosquitos.
The two most
popular conventional repellents are DEET and picaridin (a.k.a. Bayrepel).
The vast majority of what you buy in the store today use these as
active ingredients. DEET, the most common repellent in the U.S.
has been used since the late 1950s. Picaridin is far newer on the
block, introduced in Europe in 1998 and in the U.S. in 2005.
the U.S., DEET remains the repellent of choice, but there’s plenty
of reason to choose otherwise. Transdermal absorption of
DEET in studies has ranged
from 5-17% in humans, and absorption continues as long as the
product remains on the skin. DEET has been linked to some fatalities
in children who received multiple and extensive applications. It
has also been identified
as a neurotoxin, in that it inhibits the activity of cholinesterase,
an enzyme of the central nervous system in both insects and mammals.
A Duke University pharmacologist found
evidence in rat studies that DEET exposure resulted in “diffuse
brain cell death” in regions governing “muscle movement, learning,
memory and concentration,” poorer performance in physical and cognitive
tasks, and “behavioral changes” when used long-term.
governmental and medical organizations like the CDC and American
Academy of Pediatrics offer no conditions in their recommendation
of DEET, I’d say the risks are enough to give this Primal mind pause.
the more often and higher concentrations you use, the higher the
risk. I’d suggest reserving DEET products for limited occasions
if alternatives don’t work for you in a given situation. Also, more
vulnerable members of the population like children, pregnant women,
and those with autoimmune/neurological disorders should avoid using
DEET. On a side note, some
mosquitos are developing a resistance to DEET, including those
associated with yellow fever.
a repellent called permethrin, which is approved for use on clothes
only. Permethrin actually kills as well as repels mosquitos and
ticks, which means it’s clearly nothing to fool around with. Be
advised that even after your wash your clothes, the insecticide
remains. For the average person, there’s probably little if any
need for the risk inherent with this strong a product.
Less is known
about Picaridin. So far, studies demonstrate low toxicity (PDF),
and it appears to be the safest choice among conventional repellents.
Check out the fact sheets, but little is published (in this country
anyway) regarding ongoing study and safety reports.
clinical research, your best bet for minimizing bug bites
with naturally derived repellents are those with active ingredients
from essential oils. Oil of lemon eucalyptus appears
to be the most effective, but this can be irritating to the skin
of young children, particularly in higher concentrations. In a USDA
comparing natural repellents against DEET products, a commercial
repellent containing oil of lemon eucalyptus (Repel) was more effective
than the low concentration DEET product marketed for children. Geraniol,
a compound found in geranium plants, also looks promising as does
peppermint oil. Geranium and peppermint oils at 100% concentration
offer full protection, but the effect remains for a relatively short
amount of time (2 hours and 45 minutes, respectively).
the rest of the article
June 20, 2011
© 2011 Mark's Daily Apple
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