could "Dettol" result in resistivity of the bacteria?

I am not sure.

I was trained against this kind of product in my bacteriology training, but that was a while ago. I keep reading on the subject off and on, though.

My own instincts are to get really serious about antibacterials if there is likelihood of a pathogen around, or if you have someone in your care who is immune suppressed for reasons of some disease they are coping with. And then if I got serious, I might get much more serious than some pharma phear product.

In the meantime, I suspect these products aren't all so harmless for average person daily use - but no, I don't have links.

We've talked about this general question at a2k before though - you might do a search or look through thread titles on the Med News and Health Forum, as I think some may have posted applicable links.

Could you be more specific about why you are whooshing this stuff on your feet? Perhaps anti-odor reasons? I'm truly not knowledgeable on this, but wonder if getting the foot environment less moist isn't the better way to go. And, re feet, the culprit is often fungal, not bacterial. These are different entities. You might look some of this up on google. If foot odor is the problem, look at several sites on google or some other search engine, and look at many links - see, for example if some key research hospital sites mention it, like Mayo Clinic. Don't just look for products, but for medical center sites that talk about the problem.

And... if odor or fungus is a problem, as it is for many people, consider getting athletic shoes with air holes, or airbreathing weave. Air matters.
There's even a shoe, not athletic, but I had loafers, women's shoes, made with vents in the shoe sole... Geox was the company.