Diatomaceous Earth (DE): good for mammals, bad for bugs!
Diatomacious Earth (often referred to as "DE") is an off white talc-like powder that is the fossilized remains of marine phytoplankton. When sprinkled on a bug that has an exoskeleton (such as an ant or flea) it gets caught between their little exoskeleton joints. As they move, the DE acts like razor blades and cuts them up. But it doesn't hurt mammals. We can eat it. We do eat it! It's in lots of grain based foods because lots of grains are stored with DE to keep the bugs from eating the grain!
Die bugs! Die! Die! Die!
I have heard two explanations of how it works.
One is that on a microscopic level, the particles are very sharp looking. These particles stick to an insect and get stuck between its exoskeleton joints. As the insect moves, it gets physically cut up.
The other explanation is that it sticks to the insect and somehow causes them to dry out. I think this approach involves scratching the insects waxy layer which then allows precious moisture within the insect to get out. So their teeny tiny bug-innards turn into teeny tiny bug-innards-jerky.
A reader, Sue, in Washington state writes:
Both are true and connected. DE is almost pure silica (with some beneficial trace minerals); under a microscope, it looks like shards of glass (glass is made from silica). On any beetle-type insect that has a carapace, like fleas and cockroaches, the DE works under the shell and punctures the body, which then dehydrates and the insect dies. DE is totally nontoxic. There is no buildup of tolerance like there is to poisons because the method of killing is PHYSICAL, not chemical.
The important thing to us is that if an insect with an exoskeleton gets DE on them, they die. At the same time, we can rub it all over our skin, rub it in our hair, eat it .... whatever ... and we are unharmed.
Farmers dump diatomaceous earth by big scoops in with grains when the grains are stored. It kills the insects that want to feast on the grain. This is a great improvement over the stuff they used to put in with the grain.
Farmers feed gobs of it to animals in the hopes that it will cure whatever ails them. Many farmers swear that the stuff kills all sorts of worms in their critters.
One strange thing about DE is that for it to work, you have to keep it dry. Even morning dew can make it ineffective.
I have encountered over a dozen ignorant boobs that have proclaimed "Diatomaceous Earth does NOT work!" I have read this statement in all caps. In extra big fonts. With italics. And I've even had it screamed at me. I'm gonna stick with "ignorant boobs". On closer inspection of each case there is always a flaw. Usually the problem is that it was not used correctly. DE is not a bait. If you put a little bit in a pile somewhere, the bugs are not drawn to it and invite all their friends. I kinda wonder if the pesticide companies pay people to go to internet forums and say this sort of thing. DE is super cheap, non toxic, and generally more effective than anything the pesticide companies have to offer - so it kinda cuts into their profit margins a bit. I've been meaning to create an experiment to set the record straight on this topic, but a participant in the forums here, Stephanie, beat me to it:
I tried my own experiment with the DE to see how quickly it kills the fleas; I caught a few fleas and put them in a jar with a pinch of DE - all were dead within just a couple of hours.
It just doesn't get any more clear than that.
How safe is it?
The only concern about this stuff is that if you throw it into the air, you can make a big cloud of the stuff. Breathing that in can irritate your lungs. Just as breathing in anything other than pure air can irritate your lungs. The same concern applies to pastry flour, talcum powder, corn starch or dust on the wind from outside. The dust that gets into the air from emptying your vacuum cleaner bag is probably far worse for you than DE dust.
I have heard from two people that said that they won't use diatomaceous earth anymore because "the tiny particles cut my lungs!" --- (deep sigh goes here) All I can say is "Did you actually examine your lung with a microscope and watch the DE cut into it?" - of course, they did not. I think the truth behind these reports is that these folks heard how DE works, and when they would breath in the dust, it would make them cough - just as breathing in flour or corn starch would make you cough. And then they thought of the sharpness at a microscopic level. My understanding is that when DE becomes moist, the sharp thing is no longer happening. That's why you have to keep it dry when you use it.
gimmie gimmie gimmie!
There are a lot of varieties of Diatomaceous Earth (DE), so when you are shopping, be sure to get the right stuff!
I strongly suggest that you get food grade DE. Some people make 3% of the food they eat be DE. I don't fully understand why they eat that much, but ... oh well. I do know that DE is used heavily in storing grains - so you are probably already eating lots of DE every time you eat any commerical grains.
Other people feed it to their animals. Again, a bit of a mystery to me. Farmers think that it will reduce parasites, but I don't see how that will work.
Some places sell the DE mixed with other stuff. And that is something I do not recommend. When I see a label that says "97% diatomaceous earth" I have to wonder what the other 3% is. If the packaging is about killing bugs, is it some sort of toxin? Did they add something like borates or pyrethrin for a little extra kick? I don't want that!
Some places sell DE that is for swimming pool filters - that is definitely what you do NOT want.
Some places sell an 8 ounce shaker. I think it is wise to get at least a few pounds of the stuff. It keeps well (it's already millions of years old) and is useful for so many things. And if you get too little, you are likely to not use enough.
So I've done a lot of research on this .... and I've used DE from about eight different sources ... and here is what I'm recommending: This stuff mentions in their ad what rate to feed it to your pets. That convinces me that it is food grade and does not have added toxic gick. Further, it has a damn good price per pound. And the shipping costs are reasonable too.
more!
I have more to say about DE about using it to solve specific problems:
I have also heard of folks needing help with bedbugs, and so I spent a few hours researching to discover that the best solution was DE.
Bonus pics!
A reader, A. C. Bryant, wrote to me and said that she is has spent time as a scientist studying diatoms! She then sent me a bunch of info and pics to paste on this page:
Most of these are dead because I mixed them with acid to remove the organics before I cleaned them and mounted them permanently on slides. When they die, most of them will come apart so most of these are views of half of the shell. The tendency is for them to lay flat as they settle and this gives us a great view for identification. Most of these I'm naming from memory so may not be entirely accurate as to species but are pretty postive for genus. Measurements are in microns.
(click on an image to see it in freaky big size)
These images are all copyright © A. C. Bryant
All these photos were taken under a light microscope, a zeiss, with a microscope mounted camera. Some are in black and white in order to bring out shadows needed for something specific. Most are in color and the amazing colors you're seeing are because the light reflects on them much like glass. They are very similar.
If you note in the photos you can see how they are cupped to accept their other half. They tend to fit together with each half of the shell much like a petri dish, one side slightly larger than the other, with the organic elements set safely inside. They reproduce multiple ways, via division, auxospore or even sexually to regain size, as they get smaller with each division.
And as a side note, Diatoms make up about 98% of the phytoplankton out there, and about 60% (or more) of the oxygen in the world. They are as essential to our life as our own hearts.
DE is
just very old, or sometimes not so old, dried out Diatoms shells. They
are primarily silica, which means that they act like glass in many
respects. They don't react with many other compounds, degrade very
slowly, are brittle and sharp and largely inert. While this makes them
chemically invisible to people and animals and kills via physical...or
rather mechanical...means, via cutting, it also works as inert material
within the gut, filling it up with something they can't process and
blocking further feeding or digesting.
For more information on DE, and to visit with folks about DE, Click Here!
