title: Determination of ranges for reporting pollen aeroallergen levels in the Washington, DC, metropolitan area.
abstract: BACKGROUND
  Local aeroallergen monitoring provides useful information for the atopic patient and medical community. Currently, National Allergy Bureau (NAB) ranges are used for reporting pollen count levels in the Washington, DC, area.
  
  
  OBJECTIVE
  To determine standard range criteria (low, moderate, high, and very high) for the reporting of specific tree, grass, and weed aeroallergens representative of the Washington, DC, metropolitan region.
  
  
  METHODS
  Atmospheric sampling for pollen aeroallergens was performed using a volumetric rotating-arm impaction sampler (model 40 Rotorod, SDI Company, Plymouth Meeting, PA). The cumulative pollen count, over a 12-year period (1998-2009), was determined for specific pollen aeroallergens. Local ranges were developed using methodology previously employed to determine NAB ranges. A comparison was made between NAB and Washington, DC, area ranges.
  
  
  RESULTS
  The local median count, and low and moderate range criteria, are markedly lower than NAB range counts for tree, grass, and weed pollen. The NAB 99th percentile (high) count is significantly higher for grass and weed pollen but lower for tree pollen. Using new local range criteria, an increase was seen in the number of high days recorded for weed pollen (1,300%), grass pollen (258.6%), and tree pollen (11.8%). Previously, using NAB range criteria, no very high days were reported for grass and weed pollen over the 12-year period.
  
  
  CONCLUSIONS
  Washington, DC, ranges establish more relevant reporting standards for our local patient population and will allow for comparison with reporting levels developed for sampling locations nationwide as well as with other regional sites.
authors.affiliation: Department of Allergy and Immunology, Walter Reed Army Medical Center, Washington, DC, USA. Susan.Kosisky@amedd.army.mil
authors.forename: Susan E
authors.initials: SE
authors.lastname: Kosisky
authors.forename: Mariko S
authors.initials: MS
authors.lastname: Marks
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Yacovone
authors.forename: Michael R
authors.initials: MR
authors.lastname: Nelson
mesh_terms: D000485:Allergens / Q000032:analysis*; D004219:District of Columbia; D004784:Environmental Monitoring; D006801:Humans; D006109:Poaceae / Q000737:chemistry; D011058:Pollen / Q000737:chemistry*; D012621:Seasons; D014197:Trees / Q000737:chemistry
chemical_list: D000485:Allergens