Hey I'm not a diplomat but I believe the problem with this specific problem is that in the the case of 'right to clean environment' how to you protect your rights? Do you sue your neighbor for litter or the company down the street for emissions? How do you prove that emissions are out of control? Also how do developing nations who may not have the legal strength who are just as affected by pollution from developed nations exercise their rights?
Now the question of a slippery slope could be that with a right to clean environment developed nations could stifle growth and innovation in developing nations citing clean environment worries (maybe Nigeria and oil). This could go way deeper than oil however as any country trying to harvest any sort of natural resource can face scrutiny and potential action. In an extreme example developed nations could then say 'we will mine these resources because we can do it less intensively' robbing nations of potential nation building revenue. How would you combat this? Maybe a 'right to develop' and boom rights dilution and authoritative in nature. Perhaps am extreme example but extreme isn't too far with people involved.
Now the question of a slippery slope could be that with a right to clean environment developed nations could stifle growth and innovation in developing nations citing clean environment worries (maybe Nigeria and oil). This could go way deeper than oil however as any country trying to harvest any sort of natural resource can face scrutiny and potential action. In an extreme example developed nations could then say 'we will mine these resources because we can do it less intensively' robbing nations of potential nation building revenue. How would you combat this? Maybe a 'right to develop' and boom rights dilution and authoritative in nature. Perhaps am extreme example but extreme isn't too far with people involved.