|Artistic WikiCommons photo of silica beads|
Okay, not really - at least, I'm pretty sure this isn't the case. This topic comes out of a conversation I had with a friend the other day and she told me that the silica packets you get in shoe boxes, electronic components, and even bottles of vitamins, can be reused to help keep other of your items dry. I did some internet research and this is the case! I must be coming in on the tail end of this super recycling idea because there were tons of articles about this exact subject - for instance, on the Mother Nature News Network, an Illinois blogger (Cy Tottleben) describes all the different uses for silica packets, such as, if you get your cell phone wet, placing it in a bag with silica packets overnite will help dry it out (Here is also a Green Yahoo article on this exact subject. eHow has a nifty guide on "How to Recharge Silica Gel" so you can use it over and over. The article states that silica can absorb up to 40% of its weight in moisture.
The other part of this conversation was a little different. She also said that silica packets, thrown into the landfill could have a negative impact on the water table. At first, I gasped and said, "omg, NO!" but when I got home and reflected on this for half a second I realized that might not be the case. Duh, such an alarmist I am! But, I also want to write about things that at least have some basis in reality, so I did another internet search about whether or not silica could indeed deplete our already threatened water supply if they are thrown willy-nilly into the landfill. I mean, think about it, what if all the silica packets in the landfill all suddenly decided to absorb 40% of its weight in water? First, it would suck up all the nastiness in the landfill, then it would start leeching water from the aquifer, right?!
My searches were not exactly fruitful in this regard. But there are apparently a couple of things to keep in mind when disposing of silica packets. Articlesbase.com states that there are certain types of characteristics to look for and avoid when using silica. Blue silica is most likely silica impregnated with carcinogenic Cobalt Chloride and should not only be avoided in reusing, but should also be disposed of as hazardous waste. The Cobalt Chloride acts as a moisture indicator, turning pinkish when the silica has fully absorbed all the liquid it can hold.
Wikipedia's article on Silica Gel has this to say:
Silica gel is non-toxic, non-flammable, and non-reactive and stable with ordinary usage. It will react with hydrogen fluoride, fluorine, oxygen difluoride, chlorine trifluoride, strong acids, strong bases, and oxidizers. Silica gel is irritating to the respiratory tract, may cause irritation of the digestive tract, and dust from the beads may cause irritation to the skin and eyes, so precautions should be taken . Some of the beads may be doped with a moisture indicator, such as cobalt(II) chloride, which is toxic and may be carcinogenic. Cobalt (II) chloride is deep blue when dry (anhydrous) and pink when moist (hydrated).So, it reacts to a few different chemicals or states, talks about the toxicity of Cobalt Chloride, and notes the potential problem of inhaling Crystalline silica dust. Use your best judgement, of course, in how you use this information.
Crystalline silica dust can cause silicosis but synthetic amorphous silica gel is non-friable, and so does not cause silicosis.
I ended up not seeing anything about potential moisture vampirism of our water table when throwing these things away, but care should still be taken since there may be a chance they will meet up with a reactive chemical in the landfill.
I don't really know that, however, so before I started this post I emailed the customer service people at my utilities company and sent them the following:
Hi, I'm a Gainesville resident and I don't know if this is the place to find a contact for an environmental engineer or other waste management representative that I could ask a question regarding silica packets and our landfill. My question is two-fold:We'll see if I get a reply - I should add that I said I had one question but then proceeded to ask two - so much for editing carefully before submitting! My next step would be to call the waste management place directly and ask my somewhat silly questions. It seems like they've got reasonable people working there, though, since I reported (almost exactly one year ago) on their efforts to expand the recycling availability for our area. Anybody care to weigh in?
1. What are the odds of a silica packet or packets coming into contact with the substances that can cause it to become toxic if they are disposed of in the landfill?
2. This may seem like an odd question, but what is the likelihood that silica packets could have an impact on the Florida aquifer?
I am researching this topic for my environmental Blogspot blog, The Accidental Environmentalist. Thank you for any help you can provide in directing these questions to the correct party.