Am I correct in assuming that reverse osmosis is ultimately the best way to purify water?
In When Technology Fails by Matthew Stein, p. 74, Stein says, "Boiling your water will kill microorganisms, but will usually have no effect on chemical or radioactive pollutants. Distillation will kill all kinds of microorganisms, but simple distillers will not remove volatile organic compounds since they evaporate and condensed along with water vapor. To remove volatile organic compounds, more advanced distillers include either fractional distillation or an activated carbon cartridge to remove these pollutants. Reverse osmosis and activates carbon filters will remove most organic compounds."
This book is over 25 years old, so my question is concerning the nature of distilling over reverse osmosis. In a survival situation, I'm not sure if reverse osmosis is an option. Is there a way to naturally do this, or is modern technology required?