Deet As An Insecticide

I found this one in the general plumbing of news that is the delight of the internet.

If someone in the U.K. thinks that DEET (N,N-Diethyl-meta-toluamide) is safe, then somebody is clearly worried that it is not.

Mosquitoes are very dangerous, and DEET is one of the most powerful ways we have to get rid of mosquitoes.

Mosquitoes are “vectors;” that is, they transmit disease.  Moreover, their tricky little immune systems seem to keep the diseases from harming them in the slightest.

Mosquitoes carry diseases that harm not only humans (malaria, encephalitis, yellow fever, dengue, West Nile virus) but also animals, including even man’s best friend (dog heart worm).

About a million humans a year die from mosquito-borne illnesses.

These are serious diseases.

The only one of these I have had any direct personal experience with is malaria.  That was long ago in France, in someone who had not taken appropriate chemoprophylaxis.

That means taking antimalarial medication before anything happens.

Malaria can kill, and definitely is not pretty.

Evolution has dealt the best it can with the way malaria has ravaged the African population and its descendants throughout the world.

Sickle cell anemia in carriers seems to confer some serious resistance to malaria.  Evolutionary, this could help explain why sickle cell anemia persists in the earth’s population.

On top of this, global warming (with rising water levels, making the earth both hotter and more moist) seems to be raising the incidence of malaria in the world.

So humans have a vested interest in keeping mosquitoes off themselves (and their animals).

The folks in the British article cited above first were concerned that people were using low and ineffective concentrations of DEET.

Although I could not find the exact study to which the British folks refer, I was able to confirm that pregnant women should avoid going to Thailand if they possibly can.

According to the Daily Mail report — and my research online — DEET seems to cross the placenta, as it can be found in babies of Mommies who have used it, but no ill effects in children have been documented at this time.

Why am I so worried?  This agent seems to have been around for quite a while, since World War II, for jungle combat protection.  Most folks seem to think it has a pretty impressive track record.

Back to the original report from London.

They quote a spokeswoman from the London School of Hygiene and Tropical Medicine saying, “If DEET caused serious health problems, we would know about it by now.”

Turns out her real worry is about dengue fever being endemic to Brazil and transmitted by Aedes mosquitoes.

Plenty of U.K. soccer fans are there for the World Cup, and she wants to warn them make sure they take appropriate medical precautions.

Since I cannot find a single study suggesting U.K. sports fans are more intellectually endowed than American sports fans, I am concerned, too.

I checked toxicity reviews in the National Library of Medicine.  After what sounds like pretty hefty oral administration to rats, over a couple of rat generations, the only possible result they observed was “increased locomotor exploration,”  which sounds to me an awful lot like an American sports fan in front of a television going into the kitchen looking for beer. But on a more serious note, (I will give the sports fan a rest for a little while) much more serious problems have been noted by researchers.

Something wrong with animal embryos.

Irritation after intradermal depot injections?

Some kind of neurotoxic effects?

Six young girls died of encephalopathies? (Yes, that means brain disease.)

I can’t get more specific data.  It doesn’t much look like other folks can either.

There may or may not be a problem.  The jury is out.

If you want more data, here is some eminently readable stuff from the folks at the poison control center. I can link to some PDF factsheets that you can download (or they will load into a separate window) if you have the free Adobe Acrobat reader software.

If you prefer you information directly from government agencies, that is available, too.

Like the Environmental Protection Agency.

The EPA makes s dramatic request.

Read the label.

Here is the real problem.  Most people — including many of the patients I see — simply do not make logical decisions.  A lot of people seem to me to make decisions on an emotional basis, whether or not they admit it.

People actually do not seem to check out facts before they make a decision.  They tend to check things out afterward, to validate a decision already made.

The very first article I ever read about marketing — I think I was in either junior high or high school — was about magazine advertisements for Fords and Chevys.  It seemed that people would read the advertisement for the car they had already bought, to verify the decision already made.

I was shocked, but had been impressed enough by this to remember it many years later when a woman friend, whom I considered particularly intelligent, chose one of the newer Volkswagens because she had good memories of the “bug” so popular in the sixties.  She did not seem particularly well-versed in any mechanical specifics of the car.

People seem to be making medical decisions in this way, too.

It seems to me that parents of young babies are exposing their beloved toddlers to potential death from communicable diseases by declining to get them vaccinated.

Although many of these people may be requesting religious exemptions, in our wonderful land of religious freedom, they are risking not only the lives of their children but the health of their communities.

They may actually start simply by thinking that needles do hurt and so babies should not get them.

Oy!

Once I had a patient who told me humans are smart and their decisions are rational.  I never answered him.  It just isn’t so. Ask Mr. Spock from Star Trek!

If it were, I doubt psychiatry and psychology would be as useful as they are to help folks (who often make decisions they regret) feel better.

I had drummed into my head a long time ago the notion of “informed consent.”  I discuss alternative treatments for psychiatric ailments all the time.  I do spend the overwhelming majority of my time discussing the advantages and risks of that which I give most often.

Oh, so many times I have dealt with People who say, “natural is good.  All your chemical stuff is bad.”

I have tried to be logical, gently telling that vitamins and micro-nutrients are “chemical” with known structures and teency carbon atoms and such.

Never got very far that way.

I have waved my arms aggressively in the air and said (or yelled):

“Earthquakes are natural.”

“Tidal waves are natural.”

Of course, me being me, I offer natural alternatives when they seem to me worthy of consideration.

Sometimes patients listen.

Double Oy!

Of course as Americans, most of us really do, I think, believe deep down that “all men (and women) are created equal.

It seems to me to be very difficult for a lot of people to believe that anyone other than they can actually be in possession of some knowledge they do not.

I have always been more than a little taken aback by people who never seem to ask questions.  In most cases they are both harmless and free.

The only cost is the minimal embarrassment that comes from an onlooker determining you did not already know the answer.

Please, please, if you are going to expose yourself or a loved one to mosquito bites that may carry a potentially deadly illness, at least read DEET label.

If you persist in believing that “natural” is better, check out the data on compounds that may be helpful in some situations. You can ask a doctor. Me, I’m not all that shocked that a chemical could be accused of causing the kind of illness it is supposed to prevent.

Everything in life, for people who are at least trying to use their rational thought processes to solve a problem, should answer a question like “is it for me?” by doing a balance of advantages and risks. You can ask a librarian or someone internet savvy to help you research on the net.

Just know that people sometimes have “agendas”.

Realize that someone who has something to sell you may not be the most objective one to ask.

It is your money, as well as your loved ones, that we are talking about.

The one thing you cannot afford is not to ask.