A graphic which has circulated online for years attempts to explain the colored squares which appear on tubes of various products. It is claimed that different colored squares on tube packaging indicates the chemical content of the product. Today we’ll take a look at this claim.

It’s not true.

Squares printed on tubes are called “eye marks” and used in the manufacturing process. Let’s first take a closer look one version of the claim which has circulated for several years.

Did you know squares on tubes mean something?
Green: All natural
Red: Some natural, but most chemicals
Black: Only chemicals are used.

Another variation claims:

Black/Blue line: 100% chemical
Red Line: 50% chemical, 50% natural
Green Line: 100% natural

Eye Marks

In reality, squares found printed on tubes are merely marks used in the manufacturing process. They are referred to as “eye marks” and are read by a sensor in order to detect and align squeeze tubes.

Typically the color of the square is also a color of something else being printed on that side of the tube. Tubes of Crest toothpaste, for example, often have blue writing and matching blue eye marks on the back of the product.

Chemical vs Natural

The simplistic – and completely incorrect – explanation in the false assertion about does not explain the difference between “chemical” versus “natural.” The world around us is full of chemicals which occur naturally. Or, to quote the definition of “chemical” on about.com: Everything is chemical.

History

The trends chart below shows search interest in “squares on tubes” which surged in early 2013 and waned after that. We experienced small surges in interest in late 2014, and again in mid-2015.

Bottom Line

Squares printed on tubes have absolutely nothing to do with the chemical makeup of the product inside. It is merely an eye mark used by sensors in the manufacturing process. The color of the eye mark is typically chosen from the available colors used in the artwork on the tube.

Those consumers who wish to follow the “logic” of the graphic above will find a cabinet full of green tubes, all of which will contain chemicals.

Updated July 7, 2015
First published March 2013