So then why did I take the lot, sight unseen? Because of the Rowhouse Livin' "Law of Hand-me-downs," which is, simply, Always accept hand-me-downs. Here are three reasons why:
Back to the windfall . . .
Why does everyone use liquid soap? [...] Is liquid soap more sanitary? I found one secondary source that says "[g]erms can grow on bar soap." But wouldn't viruses, molds, and bacteria just wash off your hands with the mechanical action of washing and rinsing, and the chemical action of soap micelles forming around them? And what bacteria can grow on bar soap, anyway? I thought one of the basic (ha-ha) things about soap was that it lyses bacteria when the business end of a hydrophobic-hydophilic soap molecule disrupts a bacterium's lipid membrane. There must be more types of bacteria in heaven and earth, Horatio, than are dreamt of in my philosophy.(Internal links omitted. Pretentious reference to Shakespeare retained.)
According to a series of tests conducted in the early 1980s, bars of soap are often covered with bacteria and carry a higher load than you'd find inside a liquid dispenser. But no one knows for sure whether this dirty soap will actually transfer its germs to your hands during a wash.I always understood that it doesn't matter what texture of soap you use, because any soap works in two ways, due to its chemical makeup. First, the soap molecule disrupts a bacterium's cell membrane. Two, the friction of rubbing your hands together, plus the slipperiness of the basic (as opposed to acidic) soap solution you create by lathering up, plus the rinsing action of water, all work together to mechanically remove dirt, bacteria, and viruses from your skin. The Mayo Clinic agrees, telling us essentially, just wash yer dang hands, and it doesn't matter if you use liquid, bar or powder soap.
In fact, what little clinical evidence there is suggests that dirty soap isn't so bad. A study from 1965 and another from 1988 used similar methodologies: Researchers coated bars of soap in the lab with E. coli and other nasty bacteria, and then gave them to test subjects for a vigorous hand-wash. Both teams found no transfer of contamination from the dirty soap. However, both studies were tainted by potential conflicts of interest: The first was conducted by Procter & Gamble, and the second came from the Dial Corp.
Still, there's no good evidence to contradict these studies, and it's likely that the bacteria on a dirty bar would just wash off when you rinsed your hands. In other words, you'd be cleaning the soap as you cleaned your hands.