First things first.... You guys need to clarify "SAND".
If you are talking about actual sand (AKA PLAY SAND) then the main issues here are the sand being ingested... Possible causing impaction, which I will agree is a small risk.... But why would any loving pet owner put their pet at risk?
The only other issue is the bacteria which has been mentioned many times, sand known for harboring all sorts of bacteria, whether your beardie stools in the sand or not, it still exists, and can just as easily infest your pet... I challenge you sand users out there to a fecal test, lets see how many come back with a clean bill of health.
Now... If we are talking about "CalciSand" or "ReptiSand" (WHICH ISN'T SAND AT ALL) It's CALCIUM CARBONATE, is nothing like their natural habitat, and is wrong in soooo many ways!!
Many of you may recognize Calcium Carbonate as the same leading ingredient in a popular antacid that humans frequently consume... Have you ever read the warning labels for us off a pack of Rolaids??
Do not take calcium carbonate as an antacid for more than 2 weeks unless your doctor tells you to.
We are instructed to avoid using this product for longer than 2 weeks unless being monitored by a doctor. Our reptiles are placed on this stuff for months and years at a time. If it isn't safe for us to use for longer than 2 weeks, what make you believe it is safe for your reptile?
The U.S National Library of Medicine and the National Institutes of Health also has instructions for what to do if you accidentally overdose.
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
Humans are hundreds, if not thousands of times larger than most reptiles. We have safe handling instructions for calcium carbonate, instructions for limited use of calcium carbonate, and what to do if we overdose on calcium carbonate. How could anyone believe this stuff, which is apparently a risk to humans if ingested more than prescribed, is safe for an animal a fraction of our weight?
One of the most common uses for CC is in antacids. This mineral has the ability to neutralize stomach acids. Neutralizing the stomach acids in humans when they don't feel well is great. As a medication serving this purpose it is wonderful. For reptiles, this is downright dangerous.
As your reptile eats stray food items on the calcium sand, insects in the calcium sand, or randomly licks and consumes the calcium sand, it is also "medicating" itself with an antacid. The more it consumes, the more neutralized the acid in the stomach becomes. In high doses, this can easily lead to an impaction as the reptiles acid would become so neutralized that it would no longer be able to digest any additional calcium sand. The reptiles ability to digest its food adequately can be impaired or can even be halted when excessive amounts have been ingested.
It can also cause constipation. This in itself can be lethal as the body is required to expel the waste and byproducts from the foods consumed. If these are not expelled, toxicity can easily and readily become a serious issue. Toxic waste, once entered into the blood stream, can be fatal.
In excessive doses, calcium carbonate is also noted as causing hypercalcemia. Hypercalcemia is an excessive amount of calcium in the blood. This can lead to muscle weakness, psychological issues, nerve damage, spinal column curvature, and other serious issues.
The dust produced by Calcium Sand can be inhaled. As your reptile stirs the dust up and inhales the dust produced and made airborne, they could begin to experience eye and lung irritation.
The ingestion of calcium sand , coupled with their calcium dish you should be providing as well as the dusting of their feeder insects can easily result in devastating consequences. Don't use this stuff and help educate anyone who tries to tell you otherwise.
Anyone saying they are replicating their natural habitat... You are mistaken.
Australlian desert is not soft sand like the Mojave, or Baja deserts... like others before me have mentioned, they are hard packed sand, and if you did a little research on the behaviours of bearded dragons you would learn they dwell mainly in, and on rock formations.