When hinting at a handy, DIY cleanup alternative, I stressed that North was nowhere near the baking soda sprinkled out and that it was cleaned up before he got a sneak sniff.
To understand why these substances are dangerous, I've gotta get a little scientific here so bear with me. Baking soda is another name for sodium bicarbonate. Baking powder, on the other hand, combines that sodium bicarbonate with an acid such as cream of tartar, sodium aluminum sulphate or calcium acid phosphate. Both function as leavening agents in baked goods; they create a gas which causes doughs to rise.
If you're not yet getting a mental image of the dangers, if your dog eats a large amount of these powders, it creates mayhem in the tummy with an electrolyte imbalance which can result in muscle spasms or even congestive heart failure. To be safe, keep both the containers of baking soda and baking powder out of pups' reach (although baked in small amounts into treats is less dangerous), and immediately clean up if spilled near a nosy nose.
Source: Flickr User JOE M500