I can't find an authoritative answer to the question @rumtscho asked me here about the concentration of sodium bicarbonate, mixtures of which I've come to rely on as a cleaning and sanitizing solution for refrigerators.
I've seen just about any combination you can think of:
With just enough water to form a paste. With water and vinegar. With lots of water. 5% dilution in water. 0.5% dilution in water.
Most 'recipes' are not very exact. I've also read that it can be harmful, so the issue is not without interest. Especially as I've been cleaning my fridge with the 5% dilution.
Others, on the Internet, claim that it's a harmless substance and recommend it against stomach pains.