Gloves turning yellow with use? - (Nov/23/2013 )

I guess many people have noticed that for some people gloves start to turn yellow when in contact with their skin. I know this happens for nitrile gloves and I think it also happens with latex. Does anyone know the cause and why it doesn't happen for everyone?

Perfect GWAS project.

From a first thought I'd think of a mixture of skin abrasion particles (with pigments), sweat, and some dirt. Also some remains of creams and lotions (with pigments sometimes). Anyway the colour might come from the skin pigments and/or degradation/decomposition products of all the mentioned ingredients.
But well just some thoughts, not knowledge
 
edit: have a look here
"This is usually caused by the chemical reaction between your skin and the gloves. Before putting on gloves, your hands might come in contact with copper, iron or metal material, such as coins, or you may have heavy acidic perspiration in your hands. This can usually cause brown stains when wearing gloves. These brown stains do not affect the barrier properties of gloves."

hobglobin on Sat Nov 23 18:05:03 2013 said:

From a first thought I'd think of a mixture of skin abrasion particles (with pigments), sweat, and some dirt. Also some remains of creams and lotions (with pigments sometimes). Anyway the colour might come from the skin pigments and/or degradation/decomposition products of all the mentioned ingredients.
But well just some thoughts, not knowledge
 
edit: have a look here
"This is usually caused by the chemical reaction between your skin and the gloves. Before putting on gloves, your hands might come in contact with copper, iron or metal material, such as coins, or you may have heavy acidic perspiration in your hands. This can usually cause brown stains when wearing gloves. These brown stains do not affect the barrier properties of gloves."

I found that link as well but am left unsatisfied by their vague reference to "the chemical reaction"! I wash my hands every time I exit the lab so they're washed several times a day and I seldom handle metals. It's plausible that my perspiration contains some acid but I wonder why it doesn't apply to us all.

Well latex is natural rubber, which is made of polyisoprene chains that are vulcanised by a reaction with sulphur for the cross-chains. This sulphur then reacts with metals or even traces of them you have on your hands (coins, rings, door knobs, tabs/faucets, all other surfaces out of metal you may touch). The result should be a sulfide, but better ask a chemist . Not sure how acidic environment is important here or if it's alone enough, perhaps it dissolves sulphur out of the polymer? Anyway your skin has naturally a pH less than 7 (acid mantle) and according to wikipedia between 4.5 and 6.2 so differs quite substantially between different persons.

Anyway as long as not H₂S is developing in the gloves I won't care too much .

Any change in colour, elasticity/rigidity,... are indicatives that the gloves should be changed. Even if it doesn't happen, manufacturers recommend to change them every few hours due change in the porosity and permeability of the polymers that diminish the effective protection.

Anyway, always check the chemical compatibility of the gloves you are using.