Following an investigation of the relationship between pesticide tolerances and safety, it is concluded that pesticide tolerances are not relevant as safety standards. This conclusion is based upon the findings that theoretical exposures to legal levels of pesticides in the diet may pose greater than negligible risks, while exposures to most illegal residues are of no apparent toxicological significance. Thus, the common and logical views that "legal" residues are "safe" while "illegal" residues are "unsafe" are not supported by scientific evidence. Pesticide tolerances do serve important roles as enforcement tools, and tolerance enforcement programs are useful in the regulation of international trade and provide economic disincentives that may discourage pesticide misuse and emphasize compliance with regulations. Since tolerances are not appropriate as safety standards, however, legislative food safety proposals focusing upon revocation or reduction of tolerances and upon increasing enforcement capabilities may result in little benefit to public health.