In this paper we address the points raised by groups of scientists who were invited to respond to our initial critique of polychlorinated biphenyl (PCB) research in this special issue. In that article, we applied six objective criteria to more than two decades of published PCB research and concluded that much of the research was badly flawed. The PCB researchers responded to our criticisms by stating that our criteria are either irrelevant or require major revision to be applicable to health areas of research. In response, we know of no methodologic criteria or laws of probability that apply solely to toxicology research. Although we support strong environmental regulations, such should be based upon solid scientific evidence rather than upon methodologically flawed research and false belief systems. (Contains 1 table.)