Hygiene, Spit and Defog - What is the scientific truth?

[ozziworld]

I was looking at another thread about defog earlier and got me thinking about my defog practices over the last 20 years.

When I started diving in California in the late eighties I remember 95% percent of divers just used spit. I did too and did not think much of it. It did the job and was always available. There was talk about rubbing kelp on the lens, baby shampoo, toothpaste but generally, spit was it for most divers.

I moved to the Philippines and continued to use spit. As there are more Asian divers here, I noticed more and more other divers using the alternate methods to defog then got self-conscious about being among the few that spit. This may be a cultural thing.

Now that, I dive with my daughter (who finds spit gross), I use baby shampoo or toothpaste most of the time. When I do spit, I try to keep it discreet.

I don't ever recall ever having medical issues associated with poor hygiene as a result of using spit as defog. Nor do i recall anyone having any.

Are there any scientific studies or observations made regarding disease and other medical ailments as a result of using spit as defog?

Seems to me there are just perceived cultural or hygienic biases. Spit is certainly convenient and effective as defog. It can also be gross and hygienic depending on who you ask.

 

[miketsp]

Well I've been using spit for over 40 years and although I've tried many defogs, shampoos etc I still find that (my) spit is by far the best solution.
Just don't spit in your mask and then dip it in the rinse bucket - that will make you unpopular.
The only drawback to using spit I've found is that if I'm on a diving holiday where my mask never dries over many days it does have a tendency to form mold in the crevices so it's important to wash with detergent and let it dry regularly.

 

[drbill]

I've used spit for nearly 50 years and only rarely have any colds or other minor illnesses. My housemate doesn't use spit and is a clean freak. He's sick quite a bit... but then he doesn't dive!

 

[TSandM]

Well, if you think about it, the organisms in your spit are YOUR organisms. You're already living with them in some kind of reasonable harmony. So one would not really expect any significant health issues related to spitting in a mask. (Plus, you actually rinse the majority of the saliva out of the mask before diving.)

Pathogens are present in the mucous secretions of ill people, however, so having someone ELSE spit in your mask is not a great idea, nor is washing masks in a common rinse bucket.

Masks are not made of materials that tend to support bacterial growth, so, if a mask is rinsed well after diving, the likelihood of anything much remaining in it is pretty low. Thus it is not unreasonable to borrow a mask from a spitter.

 

[Zodiacdiverdave]

I think that would only be gross if you let someone else spit in your mask.
If you plan on using the stick on magnifiers instead of prescripsion lenses (if your are of that age) then I would stay clear of the other methods like de-foggers. They inhibit the lenses from sticking to the glass.
ZDD

 

[drbill]

Well, if you think about it, the organisms in your spit are YOUR organisms. You're already living with them in some kind of reasonable harmony. So one would not really expect any significant health issues related to spitting in a mask. (Plus, you actually rinse the majority of the saliva out of the mask before diving.) .

Precisely!

I have offered to give my spit to a number of other divers who complained about their de-fog not working. Strangely enough, no one has taken me up on it despite assurances that my spit worms great!

 

[Walter]

Well, if you think about it, the organisms in your spit are YOUR organisms. You're already living with them in some kind of reasonable harmony. So one would not really expect any significant health issues related to spitting in a mask.

That seems logical, but I've heard (I'm not a doctor, but you are so I'm asking) that organisms that grow in one part of the body with no problems can cause issues if moved to other parts of the body (such as the eyes). Any truth to that?

What about the folks who spit in their mask and then instead of rinsing, lick the mask clean (yes, I've actually seen two different people do this)? That can't be sanitary.

Besides, spit works, but not all that well. Any soap works much better.

 

[Bogie]

Spit works great, cheap, and easily available.

 

[TSandM]

There are some organisms one wouldn't want in the eye -- herpes, for example. Not a good idea to use spit in your mask if you have active cold sores, although, to be honest, you probably touch your face and then rub your eyes without even being aware of it. I also wouldn't spit in my mask when I had strep throat, but then, I probably wouldn't be diving then, either. The normal oral flora, especially diluted, is unlikely to cause problems.

It is known that people vary in the amount of immunoglobulin that is secreted in the saliva. I suspect that much of the defog property of spit is related to its protein content, and therefore it would seem reasonable that people would vary as to how effective a defog their saliva is. Mine is very good, but I have friends who are quite reliant on defog solution.

 

[Digger54]

If you spit in your own mask to defog it, then put the mask on and it does not significantly leak or flood any bugs are going to stay on the glass (Unless you spit a great huge wad onto the glass and left it.) The microbes can't fly. No biggie. If it works for you, do it.

I personally prefer to use the commmercial stuff. Sea Drops is my favorite. It's consistent in thickness, clean, clear, doesn't smell like anyone's bad breath and NEVER has remnants of the Resort's salad bar in it.

Folks squawk about the expense, but good heavens! Using a couple of drops per dive a bottle lasts for a whole lot of dives.