[andybarton]

The spots could be dust, or cigarette ash or may be physical damage to the glass itself. It almost looks like a 30,000 mile car windscreen...

Judging by the damage to the hood (above the "LEITZ"), I would suspect the latter, but until or unless you can actually see the lens personally, it's very difficult to tell.

If it's physical damage, then it will affect the image, in the same way, for example, that raindrops and dust on the front element do.

I wouldn't buy a lens with front element damage like this, even at what looks like a good price. $650 is around £325, which is very, very cheap for a 16mm. However, you will always be wondering what the photographs would have looked like if the element hadn't been damaged.

ffordes.com (in Scotland), have an E++ one for £599, so "your" one is almost certainly damaged.