The County Health Rankings model of population health
Explore guides and tools for improving health
Key findings from the last three years of County Health Rankings and other national reports.
Project updates, commentaries, events and news about health across the nation from the County Health Rankings & Roadmaps team.
Clean air and safe water are prerequisites for health. Poor air or water quality can be particularly detrimental to vulnerable populations such as the very young, the elderly, and those with chronic health conditions.
Clean air and water support healthy brain and body function, growth, and development. Air pollutants such as fine particulate matter, ground-level ozone, sulfur oxides, nitrogen oxides, carbon monoxide, and greenhouse gases can harm our health and the environment . Excess nitrogen and phosphorus run-off, medicines, chemicals, lead, and pesticides in water also pose threats to well-being and quality of life .
In 2014, 40 million people—1 in 8 Americans—had been diagnosed with asthma . Air pollution is associated with increased asthma rates and can aggravate asthma, emphysema, chronic bronchitis, and other lung diseases, damage airways and lungs, and increase the risk of premature death from heart or lung disease. Using 2009 data, the CDC’s Tracking Network calculates that a 10% reduction in fine particulate matter could prevent over 13,000 deaths per year in the US .
While drinking water safety is improving, a recent study estimates that contaminants in drinking water sicken up to 1.1 million people per year . Improper medicine disposal, chemical, pesticide, and microbiological contaminants in water can lead to poisoning, gastro-intestinal illnesses, eye infections, increased cancer risk, and many other health problems .
Poor surface water quality can also make lakes unsafe for swimming and wild fish unsafe for consumption. Nitrogen pollution and harmful algae blooms create toxins in water, which can lead to rashes, stomach or liver illness, respiratory problems, and neurological effects when people ingest or come into contact with polluted water. Water pollution also threatens wildlife habitats .
Communities can adopt and implement various strategies to improve and protect the quality of their air and water, supporting healthy people and environments.
The County Health Rankings use two measures to assess air and water quality:
For more information about measuring Air and Water Quality click here.
 Environmental Protection Agency. Learn about air. Last reviewed March 10, 2016. Accessed March 15, 2016.
 Environmental Protection Agency. Learn about water. Last reviewed January 28, 2014. Accessed March 4, 2014.
 Centers for Disease Control and Prevention. Asthma: 2014 National Health Interview Survey. Last reviewed March 1, 2016. Accessed March 15, 2016.
 Centers for Disease Control and Prevention. Outdoor Air: Health Impacts of Fine Particles in Air. Last reviewed December 17, 2013. Accessed March 4, 2014.
 Lambertini E, et al. Risk of Viral Acute Gastrointestinal Illness from Nondisinfected Drinking Water Distribution Systems. Environ. Sci. Technol. 2012; 46 (17):9299–9307.
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