Two Arizona cities ranked among the 100 most difficult U.S. areas to deal with spring's seasonal allergies.
According to the Asthma and Allergy Foundation of America, the annual research project categorized areas based on an independent scoring system in which zero was deemed the lowest risk and 100 was considered the highest.
Tucson, Ariz., received a score of 61.30 and ranked 61st compared to 67th the previous year. Phoenix was given a score of 58.49 and moved down three spots to 75th overall in 2013.
This year's best spring allergy cities featured Daytona Beach, Fla., Boise, Idaho and Portland, Ore. The worst regions included Jackson, Miss., Knoxville, Tenn. and Chattanooga, Tenn.