Colored Signs at Toothpastes’ Bottoms
Precaution is not a bad habit but just a common sense, and it is nothing wrong when you pay attention to some strange things, for example, to the colored block at the bottom of a toothpaste you shop for. Some people suspect that it is a hidden sign that manufactures use for marking chemicals that the paste is made of. As a matter of fact, the colored sign is nothing more than so called an “eye mark”, which tells machines used in production lines where they should cut and fold the tube.
That is all there is to it, and if you still want to know more about the paste contents, you can read the ingredients section, which all makers are required to disclose fully.