Understanding Bleach, Chlorine, Salt and Acidified Sodium Chlorite

Snoot! Nasal Cleanser uses acidified sodium chlorite, which is often called "chlorine dioxide"; it is a very safe and widely-used sanitizer and oxidizer. But because people confuse this with "chlorine bleach" that is commonly used for making clothes white in the laundry and as a sanitizer in swimming pools, we have written this page to explain the difference, and help the reader understand just how great acidified sodium chlorite is.

The term “chlorine” is used in ways that confuse the average person. The element named Chlorine is a pale yellow gas that in its pure, concentrated form is very dangerous and deadly. Yet chlorine, when combined with other elements, is far more friendly and even, at times, essential to human life. In this article, we’ll explain the difference between several terms used to describe chlorine-based chemicals, including acidified sodium chlorite (which contains chlorine dioxide) and the common use of the words “chlorine”, "bleach" and "salt".

We’ll have to be a little geeky and use some chemistry symbols as we do this so that you can see how very small differences in the elements involved actually can make a huge difference in outcomes.

Let's start with "chlorine"....

The common use of the word “chlorine” really means sodium hypochlorite, or as commonly known “bleach” or “laundry bleach.” It has decent disinfecting capabilities and has saved probably millions of lives as a result. When it is combined with an acid, it gives off pure Chlorine gas, the smell of which we are all familiar with. Most laundry bleach products have a fairly low percentage of actual sodium hypochorite in them – typically about 3-8%. Sodium hypochlorite at a stronger concentration is widely used to sanitize drinking water and also treat wastewater from sewage plants.

That’s the good news. The bad news about “laundry bleach” is that it reacts with most nitrogen compounds to form volatile and dangerous (believed to be carcinogenic or cancer-causing) compounds called “chloramines.” If your municipal water has high levels of nitrogen compounds (found in organic matter), then it will also have high chloramine levels if they treat it with "laundry bleach", sodium hypochlorite. (note: we highly recommend that you filter your tap water for chlorine and chloramines) The chemical symbol for sodium hypochlorite is Na-Cl-O, one sodium atom, one chlorine atom and one oxygen atom.

Understanding "salt" and "salinity"....

And what a difference that “O” makes. You are very familiar already (and your very life depends upon) a chlorine-based molecule that lacks that “O”: "table salt".  Ordinary “table salt”, found in our oceans, and essential to the correct operation of your body, is the combination of chlorine with sodium, known as sodium chloride, and has the symbol Na-Cl.  "Salt" is widely used and safe when consumed in moderation.

We’ve written “salt” because that term is slightly mis-used in our everyday vocabulary.  There are actually many forms of salt that exist – they are usually stable and safe compounds.  Sea water is comprised of many compounds that cause what is known as “salinity”, including sodium, chloride, magnesium, sulfates and calcium.  When the water is evaporated from sea water to make "table salt" several types of salts are left behind, the most predominant is sodium chloride. You may be familiar with the idea of "gourmet" sea salts -- these are evaporated sea water with other salts and residues that add flavors or color to them, making them "gourmet" rather than "dirty".

Another salt that you may be familiar with is potassium chloride, commonly used as a “table salt” substitute for people who want to avoid the sodium found in table salt.

So what is a bleach?

The term “bleach” is also used in a way that is very misleading. Technically, bleaches are compounds that oxidize things…often that can mean oxidizing the pigments, making them “white” (another term that is messy, because white is not a color, but the absence of color.) Laundry bleach does bleach things of course, like our hair and swimsuits in a “chlorine” swimming pool.  But many other compounds can also have the same effect. The common laundry-room product Oxi-Clean® uses sodium percarbonate, a salt-based compound, which when mixed with water releases hydrogen peroxide, an oxidizer that also “bleaches” things.

Which brings us to what is arguably the most widely-used bleaching compound in the world, chlorine dioxide, its chemical symbol is Cl-O2, a combination of chlorine and oxygen. It is made from a salt called sodium chlorite, Na-Cl-O2. Virtually all “white” paper in the world is made white from wood pulp that is bleached by chlorine dioxide. In fact, “bleached” white flour gets its colorless-ness from exposure to chlorine dioxide as well. Chlorine dioxide is in fact one of the safest bleaches available – unlike sodium hypochlorite (laundry bleach), it does not combine with other compounds to form dangerous chloramines. It is widely used to sanitize drinking water for just this reason, and the FDA allows it to be used for sanitizing meat and food processing facilities, and even applied directly to meats because of its antimicrobial properties.

Chlorine dioxide beats laundry bleach in a lot of ways...except one.

A deeper comparison to laundry bleach is interesting. Chlorine dioxide is 100-1,000 times more effective in most forms of oxidation than sodium hypochlorite – you can use a lot less for the same result. But this matters even more when we consider another use of these oxidizers: sanitation. Chlorine dioxide is probably the most effective microbicide (kills bacteria, viruses, spores, mold, etc.) known to man. It is highly effective at very low concentrations – often 1 part per million, or 1ppm.  To give you an idea of how small this is, consider a pinch of salt spread over one ton (2,000 pounds) of potato chips. That’s one part per million (1ppm). For laundry bleach to match this effectiveness, it needs to be applied at about 100ppm.

So if laundry bleach is so bad and so weak, why do we use laundry bleach rather than chlorine dioxide to make our clothes white?  Because chlorine dioxide is unstable; it degrades quickly compared to laundry bleach -- both of them degrade, but laundry bleach takes months and chlorine dioxide takes mere days.  In commercial terms, that means chlorine dioxide is not “shelf-stable”…if you put it on the shelf at a store, the chlorine dioxide might lose its strength before being purchased or used. Chlorine dioxide is sensitive to warm temperatures and sunlight and degrades quickly in the presence of either of them; in the most favorable conditions (cool temperatures, and tightly sealed in a light-proof, non-permeable container) it does not last more than 30 days. Laundry bleach “goes bad” as well, but it takes a year or so before you would notice a difference. 

A two-part solution for using chlorine dioxide.

So this is why pretty much all chlorine dioxide products come in a two-part solution; you make it when you need it. In the two-part formula, one part is sodium chlorite (notice the “t” in the chlorite) which is Na-Cl-O2, a combination of sodium, chlorine and oxygen. The other part, in the case of products that are usable by consumers, is a mild acid of some sort. In the case of Snoot!, we use lactic acid and citric acid as well. When these two parts are combined, they create acidified sodium chlorite, which contains some chlorine dioxide. Snoot! Cleanser's proprietary formulation uses catalysts and buffers to continuously produce acidified sodium chlorite for several days, extending the useful life of the Snoot! that you have mixed and put in the sprayer.