Sodium Bicarbonate

Sodium Bicarbonate (NaHCO3)  is classified as an acid salt.  When you combine a carbonic and sodium hydroxide...or an acid and a base...it reacts with other chemicals as a mild alkali.  And if exposed to heats in excess of 300F  it becomes sodium carbonate-or- washing soda.  Which is of course a more stable substance of water and carbon dioxide.
Colorado holds the largest natural deposit for baking soda in North America and seems to be trying to acquire an audience.
There are other ways of obtaining sodium bicarbonate- one of which is being manufactured chemically using the Solvay process which requires ammonia and carbon dioxide or natural natural trona.  The deposit in Green River, Wyoming has enough soda ash and sodium bicarbonate to supply the world for a thousand years.

I use baking soda for a lot of things around my house.  From face wash to internal regimen- then out to the chicken coop and into the laundry.

All baking soda is not created equally

• Pharmaceutical grade
• Food grade 
• Feed grade

Pharmaceutical grade-

When buying pharmaceutical grade baking soda you are getting something that was obtained with Good Manufacturing Practices- or GMP.  This guarantees it is pure, safe and trusted.  In order to be called pharmaceutical grade, the ingredients must be beyond 99% purity.  This is what I use in internal regimen and my face wash.  If you have not yet read up on any of the university studies on the healing properties of sodium bicarbonate- please do.  It heals.  It can act as a reset button for your body if your ph is out of balance and even soothe the nasty side effects of medications.  Tons of amazing things happen when you use it internally.

Food grade-

FDA rules allow for fillers to be put in.... like Sodium Benzoate, propyline glycol, chemical dyes etc...and of course, the FDA does not make the manufacturers list these secondary particles if they are not added when making the final product.  The raw material can contain 90% or less and have allergen fillers like corn starch and lactose.

"Industrial" grade is what you find in the pool stores and is less pure and not as fine.  It is also used when it comes to stripping cars of their paint without damaging fiberglass bodies- I never did research this "side" grade.  Going by logic- I have reason to believe it has nasty fillers and therefore can't be consumed by anything.

Feed grade-

I have in the past used the feed grade for my laundry soap and for cleaning out animal pens.  As for washing, the mild alkalinity works to lift out the fatty acids in dirt and grease into a form of soap that can be dissolved and washed away rather easily.

I have found that some of which I had once purchased, like FMC, is actually manufactured in their laboratories.  Basically by taking soda ash and then running it through a reverse process by using a centrifuge and introducing temperatures and liquids under pressure to allow sodium bicarbonate crystals to separate which allows for collection.

Feed grade is different.  Livestock is fed baking soda to help stabilize rumen ph by reducing acid conditions.  Especially dairy cows.  I personally use it with my birds- especially in the spring time.  It becomes a salt semi-replacement allowing for a dryer litter and cleaner conditions when everything is wet and nasty out. It usually runs about <80% and can be used in organic farming.