A few years ago California passed laws limiting the use of 'volital organic solvents' (VOS) since then most manufactors of floor finishes have developed water based rather than solvent based formulas. California is such a large market that it can drive changes in an entire industry. The enviromental impact has to do with the airborne release of the solvents, sounds like a small thing but thousands of gallons of the stuff is used daily and there is clear evidence that it is harmful to breath.

I expect that the entire varnish, paint and laquer industry will start to move in this direction. Some of the earlier formulas just plain sucked, but the current generation of floor finishes might even out perform the older solvent ones, and you no longer have to leave your home for a week while the fumes subside.

If you can't find your favorite old stuff I suggest you try some plain old nail polish. Comes in all kinds of colors and you can get it almost anywhwere. I particularly like the Sally Hansons HARD AS NAILS brand.