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Human Health Effects of Air Pollution

Photo of a cyclist biking on the carriage roads around Eagle Lake
Park visitor biking on carriage roads around Eagle Lake at Acadia National Park, Maine.

Human health effects associated with acute and chronic exposures to air pollution are well documented. Ozone concentrations and fine particulate concentrations have approached and exceeded the national health standards at several National Park Service (NPS) areas. Sulfur dioxide levels at Hawai'i Volcanoes National Park can cause significant human health effects. Mercury and toxic organics (e.g., pesticides, dioxins, PCBs) found in parks around the country can affect the neurological and reproductive health of wildlife and humans.

Because of possible health effects and concern for the health and safety of visitors and employees, the NPS developed ozone and fine particulate health advisory programs in several parks where levels approach or exceed the health standards. Whenever ozone or fine particulate levels exceed or are predicted to exceed health standards at these parks, NPS staff post health advisories cautioning visitors of the potential health risks associated with exposures to elevated levels. High pollution levels and the need to post pollution health advisories in national parks are disconcerting, given the values and purpose for which the parks were established, as well as visitors expectation of clean air in national parks. Most air pollution in National Parks is created outside park boundaries and when air quality conditions reach unhealthy levels in parks they are usually also unhealthy in the surrounding area. The NPS does not intend to alarm visitors but strives to provide accurate and timely information about air quality conditions.

Types of Health Effects

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Last Updated: January 10, 2013