Kordit DS, et al. - Using 2001-2008 data, researchers analyzed longitudinal trends in asthma-related emergency department visits (AREDV), air pollutant levels, pollen counts, and weather variables in the Bronx, NY. They obtained over 42,000 daily AREDV values, and used the National Climatic Data Center's Bronx station to determine daily measurements of sulfur dioxide (SO₂), carbon monoxide (CO), ozone (O₃), nitrogen dioxide (NO₂), temperature, and humidity. From the Armonk counting station near the Bronx, they obtained daily tree pollen counts. Using the Mann-Whitney test, they estimated median values for each variable to compare 2001–2004 with 2005–2008 values. Findings revealed marked decreases in AREDV, SO₂, CO, and humidity for all seasons, and decreases in NO₂ for the spring and winter from 2001 to 2008. During the same time period, increases in O₃, temperature, and spring tree pollen were reported. AREDV may be reduced by pursuing and anticipating environmental and pollutant alterations.