Rural ares are pristine compared to urban areas. The respiratory membrane in the deep lung is only 2 cells thick while the skin has a darn good barrier many layers thick with a stratum corneum that is quite resistant to penetration by microbes and most chemicals.
Mostly, rural areas ARE pristine compared to cities. But there are some small towns awash in bad air and water from some industrial something. And I lived in semi rural Switzerland where they use this horrible liquid fertilizer in sickening quantities that visibly runs off into waterways etc. but I agree, a healthier life can be had away from a big city.