Lets see, having been around these guys in Reefguys dept, they use a drysuit with blue gloves and FFMs.That sounds gross. Do you need to take any personal or equipment precautions for that?
Those underwater golf ball hunters on "Dirty Jobs" seem nuts to me...
My hat goes off to the people of the local dept's who dive. The fresh water holes that are near golf courses or developments are generally polluted like that, they also have gators and moccosins around. The depts have a designated armed overseer to keep the critters at bay if they get to inquisitive. Salt water isn't tooo bad, unless your around an older marina.