Public health consequences of hazardous substance releases.

Information collected on events and public health consequences can indicate trends in temporal and spatial distribution, chemical releases, and morbidity and mortality of emergency events. This knowledge will be useful in training first responders, planning preparedness for such events, and formulation of guidelines and policies. The impact of such training or policies should reduce both the number of events (primary prevention) and the morbidity and mortality associated with these events (secondary prevention). HSEES is the first comprehensive, state-based surveillance system of hazardous substance releases and public health consequences. Successful implementation of the system requires an active, state-based approach that uses multiple data sources and collects information in a consistent format. Good working relationships between agencies are of paramount importance for obtaining notification about events and information for the lengthy data-collection form. The system is more sensitive in recording hazardous substance releases than any existing single national database, as shown through quality-control evaluations in which HSEES data are compared with events reported to other databases. Consistency in data reporting is further evaluated by case studies sent to states on a regular basis. The five states that participated during the first 2 years of surveillance were not randomly selected. However, with additional states participating in HSEES, the representativeness of surveillance data will improve for making national estimates.