The air quality in Cincinnati is not good, although there are efforts underway to improve it. A recent study rated Cincinnati as the 8th most polluted city in the United States. In addition to general pollution problems, there are many allergens and molds in the air, making Cincinnati a bad place to live for those with seasonal allergies. The American Lung Association gives Hamilton County an "F" for ozone pollution. Pollution tends to collect in the Ohio River Valley, and since the City of Cincinnati is surround by hills and a lot of industry, the pollutants especially settle in that area.
