This is the 27th Annual Report of the American Association of Poison Control Centers' (AAPCC) National Poison Data System (NPDS). As of 1 July 2009, 60 of the nation's 60 US poison centers (PCs) uploaded case data automatically. The upload time was 19.9 [9.7, 58.7] (median [25%, 75%]) minutes, creating a near real-time national exposure and information database and surveillance system. We analyzed the case data tabulating specific indices from NPDS. The methodology was similar to that of previous years. Where changes were introduced, the differences are identified. Poison center cases with medical outcomes of death were evaluated by a team of 29 medical and clinical toxicologist reviewers using an ordinal scale of 1-6 to determine Relative Contribution to Fatality (RCF) of the exposure to the death. In 2009, 4,280,391 calls were captured by NPDS: 2,479,355 closed human exposures, 116,408 animal exposures, 1,677,403 information calls, 6,882 human confirmed nonexposures, and 343 animal confirmed nonexposures. The top 5 substance classes most frequently involved in all human exposures were analgesics (11.7%), cosmetics/personal care products (7.7%), household cleaning substances (7.4%), sedatives/hypnotics/antipsychotics (5.8%), and foreign bodies/toys/miscellaneous (4.3%). Analgesic exposures as a class increased the most rapidly (12,494 calls per year) over the last decade. The top 5 most common exposures in children age 5 or less were cosmetics/personal care products (13.0%), analgesics (9.7%), household cleaning substances (9.3%), foreign bodies/toys/miscellaneous (7.0%), and topical preparations (6.8%). Drug identification requests comprised 63.0% of all information calls. NPDS documented 1,544 human exposures resulting in death with 1,158 human fatalities judged related with an RCF of 1-Undoubtedly responsible, 2-Probably responsible, or 3-Contributory. Unintentional and intentional exposures continue to be a significant cause of morbidity and mortality in the US. The near real-time, always current status of NPDS represents a national public health resource to collect and monitor US exposure cases and information calls. The continuing mission of NPDS is to provide a nationwide infrastructure for public health surveillance for all types of exposures, public health event identification, resilience response and situational awareness tracking. NPDS is a model system for the nation and global public health.
