Surfactants allow the glyphosphate to penetrate the plant and your hands, so if you are spraying it and getting it on your hands you may as well drink it...
Who on earth would use any herbicide without using chemical resistant gloves, respirator and face mask ??
I used to manage/run an organic beef cattle property, who ended up having to use herbicides to control certain noxious weeds, so i know the arguments on both sides of the fence, and straight glyphosate would be the most benign of the broad spectrum herbicides. It's half life in clay is measured in days, it virtually breaks down instantaneously. I know of some graziers that used dam water to mix it and the suspended clays virtually killed it before it was sprayed out. Knuckleheads.
As Indylan posted, unfortunately some use surfactants that are very sus, and unbelievably these are often the consumer grade ones such as Roundup 360. The surfactants are used to enhance the uptake of the herbicide.
The full strength ones like Roundup Max and particularly Roundup Biactive are as close to 'green' as you will get for a synthetic herbicide, and IMO are actually better than some 'organic' sprays such as pine and orange oil, which to me are totally indiscriminate, kill all the insects and amphibians and merely 'burn' a lot of the weeds farmers are targeting without actually killing the rootstock, letting them re-shoot and spread.
Just my 0.02C worth.