The release of a study on Wednesday, July 18th in Science Advances could deter many national park visitors from exploring the country's national wonders in the near future. Research indicated that days where ozone levels presented a health hazard serious enough to prompt a warning by the U.S. Environmental Protection Agency (EPA) were more prevalent in national parks than in urban areas. On the west coast, Sequoia National Park has become an air pollution chart topper according to a CNN report. The... Взято отсюда