Support: Presentation Outline of Study Measuring DNA Adducts of Propylene Oxide in Workers Reportedly Exposed to PO, with Cover Letter dated 07/11/2000

摘要

This information is being submitted pursuant to current guidance issued by EPA indicating EPA's interpretation of Section 8(e) of the Toxic Substance Control Act. The Panel has made no determination as to whether a significant risk of injury to health or the environment is actually presented by the findings. This is the first study of which the Panel is aware to report DNA adducts in PO-exposed humans. The information is, however, incomplete, preliminary and of questionable significance. In particular, the sample set is very small, comprising only 8 workers each for control and exposed sample groups. Also, only minimal exposure information was provided for the eight exposed workers and no information was provided on exposures to other substances those workers may have experienced. In addition, contrary to expectations based on similar compounds, no detectable adducts were identified in control smokers, nor did the exposed smokers demonstrate higher levels ofadducts; and there was no confirmatory data (e.g., cotinine levels) on smoking status of any control or exposed worker. Furthermore, the background incidence of HPA adducts in humans has not been well established nor have their biological relevance.