Is Silica in Sand Harmful?

[Guest]

Here is some information I found from OSHA (Occupational Safety and Health Administration) about silica. I also discovered somewhere that the term "sand" refers to the size of the grain, not the contents. All of you using sand as a substrate need to make sure you know what's in it. All sand is some sort of ground up something, whether it be shells, some sort of rock, silica, quartz, limestone, etc. But, the fact that is is "sand" doesn't mean anything.What Is Silica?Silica is the name of a group of minerals containing silicon and oxygen in chemical combination having the general formula SiO2. Silica may be free, in which case only SiO2 is present, or combined, in which the SiO2 is combined chemically to some other atom or molecule. The difference is important to recognize, since the silica problem exists only with free silica. Labels on materials and product analysis sheets (e.g., MSDS sheets) must be read and instructions for use followed carefully. Types Of SilicaFree silica may occur as amorphous-free silica, of which there are many forms, and crystalline-free silica, of which there are five principal forms. Certain materials contain both amorphous- and crystalline-free silica. Silica-related diseases are associated only with crystalline-free silica. The most common examples of crystalline-free silica are beach or bank sands. A third form of free silica is fused silica which is produced by heating either the amorphous or crystalline forms. Other forms include cristobalite and tridymite. Quartz, a principal form of silica, geologically is the second most common mineral in the earth's crust. Quartz is readily found in both sedimentary and igneous rocks. Quartz content can vary among different rock types; for example, granite can contain anywhere from ten to forty percent quartz; shales have been found to average 22 percent quartz; and sandstones can average 70 percent quartz.

[Guest]

From what I understand, the danger is when you inhale the "dust". So, do the hermies inhale dust, or just walk on the substrate? That is the question. I know I inhale it when I am sifting the rocks out and stuff, but what about the hermies?

[Guest]

Oh, I forgot to add that "sand" is usually manufactured locally, because the cost of shipping is so high. So, for each of us, as we are spread out across the U.S. and beyond, our "sand" is going to be made from a different rock than the next guy. Therefore, each of us really needs to do the research on our own sand to find out what it is made from. Of course, I can't check the bag til I get home, but I bet it doesn't say.........................

[Guest]

We spent a whole week or two on this topic on another board this summer. And for the most part we all agree there's no problem with any playsand. (There were a few hold outs who decided to keep investigating which sand they bought)Here is a link I recently discovered to obtain more information on silicosis, the disease you get from inhaling silica. [URL]http://www.silicosis-injury-attorneys.com/[URL]Here's just one quote, "Silicosis is lung disease caused by overexposure to crystalline silica that workers breath when exposed to fine sand dust. The particles are much smaller than sand found at a beach and are often microscopic. The disease is one of the oldest known occupational diseases, being found in miners and potters for hundreds of years. When silica, which form the bulk of sand, rock, and mineral ores, is broken into fine dust it lodges itself into a person's lungs." While it is a disease associated with breathing crystalline silica dust, it is gotten by years of inhaling large quantities. Not the occassional stirring of a crab tank. If you are concerned about breathing the 'dust' you can simply spray the sand with water before working with it, or, remove your hermies and turn your head while you're sifting. I personnally don't think crabs would die from walking in it as they've walked around beaches for how many decades without killing off the species.Much ado about nothing I say. IMO~ Trude ~

[Guest]

Well, like Tkmilek said, is that you get silicosis or whatever it is by inhaling large amounts. We don't inhale large amounts when we just sift it or whatever, but the smell of the dust seems to live after it has become a little dirtier and settled in the tank for a while. Plus I am sure that hermit crabs will be fine, because I know when I am on the beach, if I sift some sand, it creates dust. If the dust is this common there, then I am almost positive that hermit crabs would be safe. Plus many people have had hermit crabs for many years that lived and they use play sand. I am not worried about it personally.

[Guest]

Well, personally, I am gonna start wearing a mask when I sift my sand. I can't say yet if I am gonna stop using or not, but I will definately start taking some precautions. Even the smallest bit of inhaled dust can be harmful, you know. It is definately not good for you, that's for sure.

[Guest]

I feel that I need to weigh in on this silica matter as I precipitated Crabmom investigating it when I said I had just switched to a new substrate with natural silica and had a crab die. As it turns out, my 9 year old accidently dropped the crab and thus it had nothing to do with the substrate.The substrate I use is a very fine gravel (pebble size 4 to 10 millimeters) which is made principally from quartz and thus contains silica. The manufacturer recommends that you wet it before use to remove the dust and then (after drying) use in the tank.After following the instructions I found that I have virtually no dust and the crabs seem to be as content as they are on any other substrate.In terms of the Silicosis issue,I can tell you as a nurse who has worked with patients with respiratory ailments for years, it almost exclusively affects those who are exposed to very high levels of dust. Principally contractors laborers who blast sandstone and the like.

[Guest]

Silica Sand is listed as a carcinogen because if small, respirable airborne particles are inhaled by humans it can cause a lung disease silicosis, which can in turn lead to cancer. Silica sand in and of itself is not dangerous to hermit crabs. You just have to watch whatever impurities might be present like any heavy metals (i.e. lead, mercury, etc. These are not allowed to be in play sand and the EPA monitors this very closely). Heck, a good number of the beaches they live on or near are made up largely of silica sand . The main method of respiration for hermit crabs is accomplished via the highly vascular dorsal surface of their abdomen. Due to their use of a gastropod shell (long explaination cut short here) their lungs and even their gill surface area ratio are underdeveloped compared to other crabs. While some exchange occurs here, it is not enough to fully support them. Since they don't "inhale" like we do, they cannot get silicosis. Also, play sand is washed and screeded to remove dirt and small respirable particles.That being said, I am not making a blanket statement that all silica sands are ok for hermit crabs. You should do your due diligence and find the source of the sand. Here is a post I did on Yahoo hermies group on this (I did it here too, but we don't seem to have our old library back yet):http://groups.yahoo.com/group/hermies/m ... 55014BTW-- I am the "fellow crabber" that cracked open the Estes Ultra Reef Sand story about it being 96% silica sand Generally speaking, as long as the sand is 95% or more pure silica sand it should be find to use. Just find the source and try to geta chemical analysis sheet (not just the MSDS which is too general in most cases). If you do decide to use silica sand, keep in mind you will need to pay closer attention to calcium supplementation as they will not have a ready source in their substrate as opposed to someone using aragonite or other caclium carbonate based sands. I used silica play sand for years. I only just switched to aragonite sand because I went over to a live vivarium set up where I will probably not have to change out the substrate for a year or more, so cost is not so much an issue.One last note, you may want to lay down a base of 1-2" of gravel for drainage. Some types of silica play sand can get real funky if they are allowed to stay wet. The gravel bottom under it will help with drainage and aeration.