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I recently saw a demonstration of a water filtration and purification system. In one of the demos two glasses were filled with tap water and then someone put three fingers into one of the glasses and made a scissor kick motion for about a minute or so.

Afterward, the chlorine content of both glasses was measured using standard pool maintenance equipment, and the glass that had not been touched had a noticeably higher reading.

chlorine measurement kit

Supposedly this demonstrates how rapidly chlorine is absorbed into the skin (which ostensibly makes a system that removes chlorine beneficial from a public health as well as a water taste standpoint).

Is this the only plausible explanation for the test? For example, is it possible that the agitation increases chlorine evaporation or that oils on the hand react with and neutralize the chlorine? Is chlorine absorbed that quickly through the skin?

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Stirring the water will make the chlorine evaporate faster... It's as dishonest as the AK test they do for those bracelets... – Brightblades Oct 11 '11 at 18:42
Next time the guy comes by to do the demo, get him to stir it with something other than a finger. – DJClayworth Oct 12 '11 at 19:25
can you verify that the water wasn't tampered with prior to the "test"... – jwenting Jun 12 '13 at 5:42

1 Answer 1

According to this paper from the government of Michigan:

The skin does not absorb chlorine well, but small amounts can pass through the skin when people are exposed to chlorine gas, bleach, or come into contact with water or soil containing high levels of chlorine. Although small amounts of chlorine can pass through the skin, it is eliminated from the body rapidly. Chlorine may irritate or burn the skin, especially moist areas.

Note that the paper is discussing Chlorine gas and bleach-strength solutions, as well as drinking water, which explains the reference to burning the skin.

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protected by ChrisW Apr 26 at 13:33

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