# Is it possible to prove that a hand sanitizer can kill 100% of a person's germs?

We have a project for Economics, and we need to advertise something that consumers will be willing to buy. My group thought of "improved" hand sanitizer. So, instead of it killing 99.9% germs, we would make it kill 100% germs. Although, we are having a hard time trying to prove that our hand sanitizer can, but we can't change what our product is anymore, since we only have a couple more weeks until we pass the commercial.

Can anyone help us? Thank you in advance.

• Its been found that women have more varieties of bacteria because the wash more and men have higher quantities Jul 14 '18 at 21:51
• I.e. women have morevspecies due to hygiene, men have more quantity. If you use alcohil, there still will be 1 or 2 of every 1000/5000 alive. Jul 15 '18 at 3:30
• Jul 18 '18 at 16:42

There's no realistic way to prove that your hand sanitizer can kill 100% of a person's germs. In fact there's probably no realistic hand sanitizer that can do that. The reason is that there are just so many germs. There are billions of germs on your hands. To compare, there were only a few hundred thousand people in Hiroshima when it was hit by the atomic bomb in 1945, and even that did not reach 100% fatality.

It's because it's hard to kill all germs that antibiotic resistance is a problem.

• First part of the answer isn't correct at all. You could do metagenomics analysis to say if there's presence of bacteria (or other organism) into your hand sample. Jul 14 '18 at 14:03
• @Shred not an expert on that so if you write that as an answer I'll delete this one. Jul 14 '18 at 20:56

As others have pointed out, you can't claim your sanitizer kills 100% of whatever, because it just isn't true. However, you could claim, "Product X kills nearly 100% of bacteria." Many readers will key in on "100%" and gloss over "nearly." Advertisers do this all the time.

Another alternative is to do an experiment that has an extremely small bacteria population, apply the hand sanitizer then claim 100% effectiveness. And yet another, is to conduct several experiments with different bacterial strains, find one result where 100% of the population was killed, and then make your 100% effectiveness claim. The FDA will probably come down on you hard, but my then you've probably made more than enough profit to cover the fines.

• Alternatively, you could adapt your claim to state that "sanitizer X kills 100% of bacterium Y"
– Jam
Jul 18 '18 at 18:19

As pointed by Allure, there's no way to say that a chemical agent is 100% efficient against all kind of microrganism . That's because of high rate of mutations by these, and a strong evolutionary pressure made by the use of this hand sanitizier.

To do an example: you'll make the first traitment using the hand sanitizier, and a rate of 99,9% will be killed. The remaining 0,01% will proliferate because of the ability to live and division under the hand sanitizier traitment. Consider that SDS is often used into detergent, and some strain of bacteria are capable to make the compound totally ineffective.