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Coqui
Hawaiian Integration and Reeducation Program
P.O.
Box 1880, Pahoa, HI 96778
www.HawaiianCoqui.org
808-935-5563
February
8, 2002
Leslie
K. L. Lau, M. Sc.
Toxicologist,
HEER Office
P.O.
Box 3378
Honolulu,
HI 96801
Dear
Ms. Lau:
Thank
you for your letter about the permeability constants of
caffeine.
Essentially,
your position is that, according to non-human animal
research and in vitro skin slice studies, the
permeability of caffeine through human skin is most
likely too low to pose a threat to people exposed to
spray residues.
There
are some problems with your assumptions regarding the
skin research you cite.
Those studies use concentrations of caffeine well
below that proposed for spraying to kill frogs.
The effects of caffeine on the skin differ at
these higher concentrations, as evidenced by the fact
that spray applicators are required to wear protective
clothing and gear to avoid caffeine exposure.
Spraying a cup of coffee would not require such
protection. The
point is that the physiological effects of certain
substances change beyond certain concentrations of that
substance.
In
addition, the concentrated caffeine irritates the skin,
altering its permeability.
That is, it is a well-known medical fact that
irritated, inflamed skin has greater permeability than
intact, healthy skin, due to a breakdown of the skin’s
integrity. The research studies you cite assume the skin has the same
integrity throughout the experiment.
However, the real life exposure to caffeine spray
residues can damage the skin, lowering its integrity,
and increasing its permeability to the caffeine.
And the skin wouldn’t be irritated if the
caffeine did not get inside the skin.
Also,
many people have skin cuts and irritations, particularly
on the feet, which automatically increase caffeine
absorption as compared to healthy, uncut, non-fungal
feet. And
many people in Hawaii wear open-toed shoes, sandals,
thongs, or go barefoot, bringing the skin directly in
contact with the caffeine residues.
So your citation of skin permeability studies
fails to consider the reality of skin health and
disease.
Besides
these problems with your skin permeability argument, you
fail to consider the ingestion of caffeine by hand to
mouth contact. Let
me give the following scenario as an example.
A
young mother takes her asthmatic toddler for a walk,
bringing along their poodle, Fifi.
They walk through an area that has been recently
sprayed with caffeine, and Fifi runs through the area,
collecting caffeine residue on her fur.
The child pets the dog, transferring the caffeine
to her little hands.
The family then goes to MacDonald’s for a
hamburger, fries, and a Coke.
The child ingests the caffeine on her hands with
the fries and hamburger, and washes it down with the
caffeinated beverage.
The high level of caffeine that enters the
child’s small body interacts with the asthma
medication, causing the child to experience respiratory
failure, which can lead to death.
(This ignores the effect of caffeine exposure to
poor Fifi, who will have to lick the caffeine off.)
There
could be other stories.
If the mother was pregnant and the family lived
near a sprayed site, and the mother has a birth
defective child, it could have been caused by the spray,
since caffeine is a powerful mutagen.
And the State will be liable for the damages
caused.
It
is clear that the DOH cannot make the statement that
exposure to caffeine spray residues are no threat to
human health. Even
the EPA, which is surely aware of the research on
caffeine and skin exposure, acknowledges the risk of
caffeine exposure to humans.
However,
the real issue is whether the DOH can impose this human
experiment on the Hawaii public.
As I have written in prior correspondence with
your office, human experimentation requires informed
consent. The
government has no right to expose the public to this
caffeine hazard without the public’s consent, meaning
the consent of everyone involved in this experiment.
And
deeper yet is the question that nobody in your office
has responded to. Why
is the DOH supporting a project that poisons tree frogs
and may poison everything else at the same time?
The frogs are not a health threat.
Exposure to concentrated caffeine is a health
threat. Why
endanger the public’s health to kill something that is
no threat at all? And
since the frogs eat mosquitoes, why not be supportive of
their being in Hawaii?
We’re never going to get rid of them, anyway.
Which
raises the irony that this debate is not about
eliminating the frogs, but simply attempting to control
their numbers. This
means that the need for spraying will continue, which
will continually expose the public to the caffeine.
At what point the environment becomes excessively
caffeinated remains to be discovered, and will surely be
realized only by hindsight.
In
fact, the DOH seems to have no foresight on this issue.
DOH arguments have reflected a bias towards
spraying, with the onus of proof of its hazards being
placed on me to establish.
The burden of proof of safety should placed be on
those proposing caffeine use.
To proceed with this experiment is poor public
health policy, and shows that the interests of the
public are not paramount at the DOH.
Again,
thank you for your scientific response to my letter.
I hope, however, that you can see the bigger
picture now, and understand that the killing of little
tree frogs is not worth the liability and risk of
exposing people to potentially damaging, if not lethal,
doses of caffeine.
Sincerely,
Sydney
Ross Singer
Medical
Anthropologist and Biochemist
Director,
CHIRP
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