Also, the TRI database does not include specific explanations of the reasons for changes in quantities reported by facilities. Many other factors, however, may also cause changes in reported release quantities, for example, substitution of one chemical for another, changes in accounting or estimation techniques, changes in the design of a product, or regulatory requirements. A study completed by OPPT examined how some of the above factors contributed to changes in releases and transfers between 1989 and 1990. The study found that although source reduction was a significant factor in explaining some of the changes, fluctuations in production were more frequently cited for individual facilities' increases and decreases. This is an important consideration because measuring progress in source reduction must also take into account production changes.
Source reduction is too complex to be captured by only one measure.
These data collected on Form R will help EPA better evaluate release trends and will also be critical in developing a comprehensive understanding of the effects of pollution prevention activities. The data provide EPA with a more comprehensive view of waste management practices. They shift the focus from releases to movement up the waste management hierarchy.