Medical Aid, a South African insurance comparison website, investigated the effects of environmental issues like poor water quality, pollution, sanitation and chemical exposure on the health of citizens in 103 countries around the world. The information is summarized in a report titled, “Climate Health: Where in the World is Climate Change Impacting Health the Most?” Countries with the healthiest environments Nordic countries came in at the top of the healthy list with notably cleaner land, air and water. Related: The best and worst US states for climate change Iceland has the healthiest environment, with unpolluted air, low temperature increases, clean drinking water and good sanitation.