Naked Science Forum

Life Sciences => Physiology & Medicine => Topic started by: MeganM on 29/01/2020 12:11:19

Title: Why do germs not die instantly on contact with soap?
Post by: MeganM on 29/01/2020 12:11:19

Listeners Mark & Jack want to know:

Why are we told that 'germs' need more than 20 seconds of contact with soap to kill them when washing our hands? Why isn't it instant on contact?

Any ideas?

Title: Re: Why do germs not die instantly on contact with soap?
Post by: evan_au on 30/01/2020 08:53:46

The primary purpose of scrubbing with soap and water is to dislodge germs from your skin, and wash them down the sink.

Soap does not necessarily kill the germs. That is the role of an antiseptic or an antibiotic.

Title: Re: Why do germs not die instantly on contact with soap?
Post by: Petrochemicals on 30/01/2020 17:29:51

Quote from: evan_au on 30/01/2020 08:53:46

The primary purpose of scrubbing with soap and water is to dislodge germs from your skin, and wash them down the sink.

Soap does not necessarily kill the germs. That is the role of an antiseptic or an antibiotic.

Clarifying this, soap is primarily used to cut the germ bearing grease that is on hands , scrubbing washes the germ residue away. Dish washing accomplishes only do dislodge the habitat for germs away, sterilisation is accomplished with heat, chemical or drying.

Title: Re: Why do germs not die instantly on contact with soap?
Post by: ninaholm on 08/02/2020 09:20:55

Recall that a germ is the thing that we consider any infinitesimal molecule or life form that can make us wiped out, so this incorporates infections and microbes but any Doctor tells us better