- pollution 500 years ago was something humans had lived with for a long time, making them less harmful due to evolution. - life expectancy isn't a good measur

- pollution 500 years ago was something humans had lived with for a long time, making them less harmful due to evolution. - life expectancy isn't a good measure, life quality is. - all organic pollution for the most part is something body could handle on its own. Body has easier time dealing with rotten tomato than concentrated mercury in fish that we have now.