52
votes
Accepted
Does washing hands with soap remove more germs than plain water?
Washing your hands with plain water of a normal temperature is significantly less able to effectively sanitise against bacteria, viruses, and many protozoa. The oil on your skin will hold pathogens ...
- 644
42
votes
Is vodka (or alcohol solutions with less than 60% concentration) an effective hand sanitizer against Covid-19?
A more recent study (also published by the CDC) seems to indicate that 30% might be a good enough concentration against SARS-CoV-2:
[Figure legend:] Effect of commercially available alcohols in ...
- 59.8k
29
votes
Does washing hands with soap remove more germs than plain water?
Washing your hands with plain water does reduce germs.
It just does not remove as many of them as using soap would.
Source: Same link as Michael, and sorry for the hijack -- I know this to be true ...
- 19k
20
votes
Accepted
Do pathogens have a negative ORP and beneficial bacteria a positive?
The beneficial strain of E. coli K-12 has a negative ORP. Therefore, the original claim cannot be universally true.
Furthermore, E. coli is a facultative anaerobe, which means it can survive in both ...
- 1,711
15
votes
Is house dust mostly made up of human skin?
According to Elemental concentrations and metal bioaccessibility in UK household dust Science of the Total Environment vol. 371, pages 74–81.
Household dust has many internal and external sources, ...
- 106k
13
votes
Accepted
Are antibacterial soaps better than plain soap and water?
This 2015 study, Bactericidal effects of triclosan in soap both in vitro and in vivo, suggests the most popular active ingredient, triclosan, had no effect for exposures commensurate with hand-...
- 146
12
votes
Do Ultra-violet LEDs on air hand dryers help to kill bacteria?
In 2005, a study was done comparing a number of hand drying methods:
Yamamoto Y, Ugai K, Takahashi Y. Efficiency of hand drying for removing bacteria from washed hands: comparison of paper towel ...
- 141k
11
votes
Do pathogens have a negative ORP and beneficial bacteria a positive?
Pathogens create a waste material that is poisonous to the body.
The more common definition of pathogen is that it does harm to its host - see abstract of this interesting looking paper "What is a ...
- 898
10
votes
Accepted
Did Louis Pasteur admit on his deathbed "Bernard [the inventor of terrain theory] was right"?
This can be traced to a questionable 1922 anecdote.
Okay, I have an answer now.
The original French quotation, "le terrain est tout, le microbe n’est rien," was in vogue among doctors in the ...
- 44.9k
9
votes
Accepted
Does the risk of becoming infected with COVID-19 decrease by washing hands?
Direct evidence of actual viral disease transmission via fomites (the medical term for inanimate surfaces) is unfortunately notoriously difficult to produce, according to a 2007 review:
direct ...
- 59.8k
9
votes
Accepted
Was Ignaz Semmelweis ignored by the medical community when he advocated hand washing?
1) Was Ignaz Phillip Semmelweis the first to identify or a pioneer in identifying, the importance of hygiene in these cases?
A. Ignaz Semmelweis was not the first to emphasize the significance of ...
- 22.7k
8
votes
Does washing hands with soap remove more germs than plain water?
If one would move his hands while washing hands with raw water, would that help in getting rid of bacteria and germs?
Yes. In fact it can reduce the bacteria on your hands by 77%. This is a ...
- 1,460
8
votes
Accepted
Is brushing your teeth after vomiting dangerous for your teeth?
If brushing your teeth with traces of acid in your mouth really is dangerous, shouldn't we hear about it without mentioning of vomit?
Yes, and we do (from Colgate):
You should know, however, ...
- 10.2k
8
votes
If I buy "flushable" wipes, can I flush them without problems?
This website from ThamesWater (a water management company in UK) states that they are not flushable, and even shows you why.
Other sources tell the same story:
https://www.lanesfordrains.co.uk/...
- 355
8
votes
Accepted
Are women's public restrooms dirtier and/or more bacteria-laden than the men's rooms?
A study done (1) by Ciri Science, the Cleaning Industry Research Institute, sampled 47 public restrooms to test the presence of bacteria on various bathroom surfaces and found that women’s bathrooms ...
- 30.3k
8
votes
Accepted
Are 40% of the oceans' bacteria killed by viruses every day?
According to Bacteriophage Distributions and Temporal Variability in the Ocean’s Interior mBio Nov/Dec 2017 Volume 8, e01903-17:
Phages have been
shown to kill hosts at rates of up to 20 to 40% of ...
- 106k
7
votes
Does boiling water with solid silver kill germs?
This World Health Orgainization report explores silver as a water disinfectant. It kills a wide variety of bacteria, and fungi without leaving a residue or many chemicals in the water.
Silver has ...
- 12k
6
votes
Do hand dryers in public bathrooms spread bacteria?
According to a recent research paper, "Evaluation of the potential for virus dispersal during hand drying: a comparison of three methods", jet air dryers are the "worst", while warm air dryers are ...
- 485
6
votes
Accepted
Does washing salad remove E-coli?
Indeed you're wrong.
A study reported that washing lettuce leaves with tap water for 15 s provided a log reduction of 1.16 (93.08 %) of the E. coli population, while "prolonging washing time with ...
5
votes
Accepted
Can microbes live on surfaces with less than 10% humidity?
Here is a graph from a scientific review paper by Jawad A et al. (1996) called Influence of relative humidity and suspending menstrua on survival of Acinetobacter spp. on dry surfaces. A PDF of it can ...
- 3,865
5
votes
Does alcohol-free "essential oil" mouthwash kill bacteria in your mouth?
Essential oils can definitely kill bacteria; however, the other complicating factor related to alcohol is the biofilm.
Penetrating the plaque biofilm: impact of essential oil mouthwash.
This suggests ...
- 151
4
votes
Home-made vs. commercial toothpaste?
Commercial toothpastes contain fluoride. Home-made ones don't.
Fluoride effect on cavity reduction is well-established. For example: https://www.ncbi.nlm.nih.gov/m/pubmed/16208382/
As such, your ...
- 140
4
votes
Do hand dryers in public bathrooms spread bacteria?
This paper found that air-blower hand driers were much worse than paper towels. The Dyson Airblade is a particularly bad offender.
Update: now it turns out that air-blower hand driers also suck in ...
- 15.9k
3
votes
If I buy "flushable" wipes, can I flush them without problems?
In the UK it depends on the product
The UK Water Industry (WI) has set specification WIS 4-02-06 (set in 2019) for toilet wet wipes which are fine to flush.
Any wet wipes certified fine to flush have ...
- 2,638
2
votes
Does gaunyle, derived from cow urine, work as a disinfectant?
"Gaunyle" is advertised as "organic phenyle" and "organic phenyl" and as a general disinfectant for floors - thus i believe the idea is that is an 'organic' alternative ...
- 1,625
2
votes
Is this study evidence that a fly falling into one's drink should be dipped?
The 1990 paper by Baeshin is dipping flies for 20 seconds (vs floating fly for 20 seconds) and dipping flies thrice for 20 seconds each (vs floating for 60 seconds) in some experiments using the same ...
- 1,625
1
vote
Does the risk of becoming infected with COVID-19 decrease by washing hands?
COVID-19 is, in this respect, no different than any of a million other pathogens - and hand-washing isn't a new thing.
The Global Handwashing Partnership has been working for years on promoting hand ...
- 2,949
1
vote
Accepted
Is washing hands with soap necessary when backpacking?
It is definitely worth bringing sanitizer on a hike
Germ Longevity
Bacteria and viruses die after a while on your skin - anywhere from hours to months according to the UK NHS. If you can keep your ...
- 1,325
Only top scored, non community-wiki answers of a minimum length are eligible