The Hormesis Case
Prominent hormesis researcher Edward Calabrese claims that “Data over the past decade have indicated that the field of toxicology made a crucial error regarding its most fundamental and central feature—that is, the dose response.”1 Recall from the previous chapter that hormesis consists of instances in which the direction of some biological response (e.g., growth, disease incidence, enzyme activity) changes with decreasing dose as a result of biological feedback mechanisms. Calabrese argues that toxicologists have failed to recognize that hormetic dose-response relationships predominate over others.2 Moreover, he insists that this error has both scientific importance and significant ramifications for public health and economic wellbeing. According to Calabrese, many pollutants that normally increase rates of cancer incidence or cause other harmful effects at high doses are likely to decrease the incidence of these harmful effects (below control levels) when present at low concentrations. Thus, he suggests that it may be feasible to weaken pollution regulations, thereby saving money and improving public health at the same time.3
The present chapter examines the hormesis case study and highlights the key methodological and interpretive questions that one needs to consider in order to evaluate Calabrese’s claims about the hormesis phenomenon. As chapter 3 discusses, these methodological choices have frequently been labeled “value judgments” by philosophers of science. Because the concept of a value judgment requires a good deal of unpacking, however, the present chapter merely identifies these crucial choices and saves reflections about their nature and significance for subsequent chapters.
Analyzing the methodological and interpretive choices associated with hormesis research should be of interest to a wide variety of citizens and
1. Calabrese, “Hormesis: Why It Is Important.”
2. Calabrese and Baldwin, “Toxicology Rethinks Its Central Belief”; Calabrese and Baldwin, “Hormetic Dose-response Model Is More Common”; Calabrese et al., “Hormesis Outperforms Threshold Model.”
3. See, for example, Calabrese and Baldwin, “Toxicology Rethinks Its Central Belief “; Calabrese, “Hormesis: Once Marginalized.”