appreciable risk of reproductive and developmental effects, adjusted for the exposure scenario of concern. The UEL is similar to the EPA's acute and chronic Reference Doses (RfD) and the U.S. Food and Drug Administration's Acceptable Daily Intake (ADI) except that it is specific for reproductive and developmental effects and is derived specifically for the exposure duration of concern in humans. Chapter 3 discusses how the UEL is derived in the evaluative process and how it can be compared with an anticipated human exposure such as found in the workplace. Chapter 4 sets forth a strategy for evaluating exposures for which there are few or no data on reproductive or developmental toxicity. The subcommittee's recommendations are presented in Chapter 5. This report also contains four appendixes: Appendix A contains examples of the application of the proposed evaluative process to two specific chemical agents, Appendix B describes and evaluates various sources of information on reproductive and developmental toxicity, Appendix C describes and evaluates human study designs, and Appendix D describes experimental animal study designs and discusses qualities and limitations for each type of study.