This hoorah about diatomaceous earth has been going on for over ten years now. It's gotten into internet popular legend and has grown steadily ever since.
DE can be and is useful stuff. For what it is good for. For any other purpose it's largely worthless.
Generally speaking there are two basic kinds of diatomaceous earth available. The first and usually the easiest to find is the sort you DO NOT want for any purpose other than what it is specifically labeled for and that is filtering water - typically in swimming pools. It has been heat treated to increase its crystalline silica content to improve its filtering qualities. This stuff is particularly hazardous to breathe in and should not be used around your livestock, taken internally, used in food storage or for any other purpose other than as a filtering agent. The increased crystalline silica content it contains makes it dangerous to inhale. Excellent water filtering material, dangerous pesticide. DO NOT get your DE from a swimming pool supplier.
The other type of diatomaceous earth is non-heat treated so it contains mostly amorphous silica but for the very little bit of crystalline silica it contains. ALL diatomaceous earth is mostly silica because that is what the shells of the marine diatoms it is made from were primarily composed of. Mostly silica, but only a little of it is crystalline in nature. The rest has been crushed to the point it's not particularly dangerous. It's the crystalline part that is the active, effective agent, but you only want a fairly small amount to be safe which is why the amorphous (non-crystalline) content needs to be so high.
Now diatomaceous earth is a naturally occurring material found in many places around the world so it can and often does contain other materials some of which are useless and a few of which might not be a good idea to ingest. This is where the 'food grade' part comes in. It needs to be sufficiently pure without deleterious contaminants so that you can use it without having to be worried about being poisoned by the contaminants. Just about everyone who has ever used toothpaste to brush their teeth has ingested a purified form of diatomaceous earth. It does have legitimate uses in many things we ingest or put on our skins. Used properly it is not at all dangerous.
It's the used properly part that is important here. When it is dry non-heat treated diatomaceous earth such as what we find for sale is a very fine, fluffy powder. Not toxic but it is a finely divided powder. As with any non-toxic powders we can safely tolerate a small amount of it in the air (most of us, asthmatics are more sensitive) just as we can with the common, every day dust that we all encounter. It's when the amount goes beyond a little that we can run into problems. When there is a lot of finely divided dust in the air it's not a good idea for any of us to be breathing it in whether it's DE, wheat flour, or baby powder. We can handle inhaling a little, but a lot can sometimes run us into problems. A paint store dust mask is a good idea if your local air is dry and the dust really hangs and spreads in the air. This is true for any finely divided powdery substance no matter how benign.
As for what diatomaceous earth is actually good for that's where the real rub lies. The difference between what has been proven in the lab and what some folks believe is vast. I've been using it for over ten years and find it very useful - for a few things. Otherwise it's worthless. It's great for keeping ants out of my nest boxes and feed storage cans and it helps with roaches in the feed room as well. I also use it my house under and behind cabinets, the stove, refrigerator and so on. All places where it can stay DRY. Once it becomes wet it loses all effectiveness until it dries out and something fluffs it up again. I do not believe it has any effectiveness at all when taken internally by us or by animals. If anyone has any documented studies that indicates that is does I'd like to see them.
It does seem to have some effectiveness in deterring external parasites on poultry if you mix it into their dusting holes. But only a limited effectiveness. Worth giving a try, but be ready to use something else if you get nothing from it. It can work on fire ant mounds if it stays dry which here in Florida it most certainly is not now that the rainy season has started. In April and May I've used it to good effect for at least getting the mound to move on. Come June though it's worthless.
DE can be good stuff when used properly but it's not a cure-all for anything. Worth checking out to see if it can be made to work for you, but have a backup plan in case it doesn't.
DE can be and is useful stuff. For what it is good for. For any other purpose it's largely worthless.
Generally speaking there are two basic kinds of diatomaceous earth available. The first and usually the easiest to find is the sort you DO NOT want for any purpose other than what it is specifically labeled for and that is filtering water - typically in swimming pools. It has been heat treated to increase its crystalline silica content to improve its filtering qualities. This stuff is particularly hazardous to breathe in and should not be used around your livestock, taken internally, used in food storage or for any other purpose other than as a filtering agent. The increased crystalline silica content it contains makes it dangerous to inhale. Excellent water filtering material, dangerous pesticide. DO NOT get your DE from a swimming pool supplier.
The other type of diatomaceous earth is non-heat treated so it contains mostly amorphous silica but for the very little bit of crystalline silica it contains. ALL diatomaceous earth is mostly silica because that is what the shells of the marine diatoms it is made from were primarily composed of. Mostly silica, but only a little of it is crystalline in nature. The rest has been crushed to the point it's not particularly dangerous. It's the crystalline part that is the active, effective agent, but you only want a fairly small amount to be safe which is why the amorphous (non-crystalline) content needs to be so high.
Now diatomaceous earth is a naturally occurring material found in many places around the world so it can and often does contain other materials some of which are useless and a few of which might not be a good idea to ingest. This is where the 'food grade' part comes in. It needs to be sufficiently pure without deleterious contaminants so that you can use it without having to be worried about being poisoned by the contaminants. Just about everyone who has ever used toothpaste to brush their teeth has ingested a purified form of diatomaceous earth. It does have legitimate uses in many things we ingest or put on our skins. Used properly it is not at all dangerous.
It's the used properly part that is important here. When it is dry non-heat treated diatomaceous earth such as what we find for sale is a very fine, fluffy powder. Not toxic but it is a finely divided powder. As with any non-toxic powders we can safely tolerate a small amount of it in the air (most of us, asthmatics are more sensitive) just as we can with the common, every day dust that we all encounter. It's when the amount goes beyond a little that we can run into problems. When there is a lot of finely divided dust in the air it's not a good idea for any of us to be breathing it in whether it's DE, wheat flour, or baby powder. We can handle inhaling a little, but a lot can sometimes run us into problems. A paint store dust mask is a good idea if your local air is dry and the dust really hangs and spreads in the air. This is true for any finely divided powdery substance no matter how benign.
As for what diatomaceous earth is actually good for that's where the real rub lies. The difference between what has been proven in the lab and what some folks believe is vast. I've been using it for over ten years and find it very useful - for a few things. Otherwise it's worthless. It's great for keeping ants out of my nest boxes and feed storage cans and it helps with roaches in the feed room as well. I also use it my house under and behind cabinets, the stove, refrigerator and so on. All places where it can stay DRY. Once it becomes wet it loses all effectiveness until it dries out and something fluffs it up again. I do not believe it has any effectiveness at all when taken internally by us or by animals. If anyone has any documented studies that indicates that is does I'd like to see them.
It does seem to have some effectiveness in deterring external parasites on poultry if you mix it into their dusting holes. But only a limited effectiveness. Worth giving a try, but be ready to use something else if you get nothing from it. It can work on fire ant mounds if it stays dry which here in Florida it most certainly is not now that the rainy season has started. In April and May I've used it to good effect for at least getting the mound to move on. Come June though it's worthless.
DE can be good stuff when used properly but it's not a cure-all for anything. Worth checking out to see if it can be made to work for you, but have a backup plan in case it doesn't.