if you boost a (parametric for preference) eq to highlight ssibilant sounds then chuck it through the sidechain of a compressor it forms a de-esser. Filter out any low frequency nonsense. I sometimes boost around 600-1.2khz slightly. If there's popping sounds you could always do a cheeky bit of gain editing. Nearly all the interviews i've done in odd situations have involved a bit of cutting and pasting. Plus, you can mix up the sounds and make them say rude things!!! (assuming it's recorded already. If not, get the mic slightly off the line of fire)