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This chapter shows how the major lessons of the preceding chapters apply to cases of policy‐relevant research other than hormesis. It argues that those who investigate endocrine disruption and multiple chemical sensitivity also encounter at least four major categories of value judgments: (1) choices about what topics to investigate and how to design studies; (2) decisions about what scientific terminology and definitions to employ; (3) choices about how to interpret and evaluate studies; and (4) questions about how to incorporate scientific research into policy decisions. The chapter also shows, in accordance with Chapter 4, that current university conflict‐of‐interest policies are unlikely to prevent interest groups from exerting powerful influences on these judgments. Chapter 7 also supports the central contention of Chapter 5 (i.e., that diagnosing deliberative forums is important) by showing the problematic effects of poorly designed deliberation in the MCS case and the positive consequences of well‐designed deliberation in response to endocrine disruption. Finally, the chapter shows that experts who study MCS and endocrine disruption could also gain valuable guidance by reflecting on the ethics of expertise developed in Chapter 6.

In this chapter, the current understanding of the mechanisms of endocrine disruption on the brain and nervous system are presented. Because the overwhelming majority of mechanistic studies on EDCs have focused on the actions mediated by nuclear hormone receptors, this mechanisms is described in detail. The chapter also discusses the classic transcriptional mechanisms of steroid action and the impact of EDCs on rapid signaling (non-genomic) mechanisms. It presents an overview of the enzymes and pathways involved in the biosynthesis of steroid hormones, which are critical to proper functioning of the HPA and HPG axis, and the neuroactive steroids synthesized and active in the mammalian brain. The potential for EDCs to alter metabolic enzymes, with a focus on possible targets in the metabolic blood-brain barrier, is presented as a potential, though largely unexplored, mode of EDC action in the brain.

Fish, and other vertebrates, possess both a neural control system and a hormonal one dependent on the circulation. Fish hormones may be secreted by well-defined endocrine glands or by diffuse tissue and can have profound effects on the function of target tissues or organs which possess receptor molecules recognized by specific hormones. Some endocrine activities in fish are not relevant to mammals, and vice versa. Thus fish can have chromatophores controlled hormonally to change skin colour, the same hormones having different roles in mammals. Likewise, ‘prolactin’ in fish cannot regulate lactation. Individual endocrine glands, tissues and cells of fish are described in detail and the possible roles of their hormones are discussed. Fish endocrinology is becoming increasingly important with the realization of its potential applications in aquaculture and with the recognition of the consequences of pollutant endocrine disruption.

This chapter focuses on four of the best known and most well characterized EDCs: the polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT), diethylstilbestrol (DES), and bisphenol A (BPA) as prototypical EDCs. For each compound, historical information regarding use, sources of contamination, descriptions of toxic effects, nature of endocrine disruptive mechanisms, and detailed summaries of critical research findings are highlighted. Each of these chemicals are seminal illustrative examples of EDCs that came to be recognized, defined, and considered seriously by the general public and the regulatory community. Continuing work with these well-studied chemicals continues to reveal new mechanisms of EDC action and identifying new potential health outcomes and effects, and have become important “positive control chemicals” for toxicity and chemical testing strategies and identification of emerging EDCs.

The system for regulating toxic substances in the United States is broken. It is disjointed and reactionary, lacking in information, authority, and primary prevention. The case study of bisphenol A (BPA) demonstrates a myriad of limitations with the way we evaluate, regulate, and manage toxic substances in society. The purpose of this chapter is to provide a brief overview of the current U.S. system for regulating toxic chemicals and to identify limits in that approach with particular emphasis on BPA. It provides an overview of some of the drivers shaping new approaches to chemicals regulation and management and a framework for designing more precautionary and solutions-stimulating policies in the future. The U.S. system for regulating toxic chemicals in production systems and products is relatively complex. Different types of chemicals are regulated in various ways in the U.S. system, depending on how that chemical is being used. For example, cosmetics, chemicals used in food applications, medical devices, and pharmaceuticals are regulated by the U.S. Food and Drug Administration (FDA) under the Federal Food, Drug and Cosmetics Act, and each of these types of chemical applications is regulated differently under the Act. For chemicals used in cosmetic products, the FDA has no premarket authority and can regulate a chemical ingredient only if it is mis­branded or adulterates the product. In the case of new food contact substances and uses of them (indirect food additives including chemicals that might leach out of packaging such as bottles), manufacturers are required to submit notifications, including safety data, to the FDA, except when a substance is previously regulated or considered “generally recognized as safe” because earlier evidence on that material did not indicate concerns. At the FDA, the highest evidentiary burdens are for medical devices and pharmaceuticals that have strong premarket testing requirements to ensure safety and efficacy. Chemicals in many consumer products, such as toys, are regulated by the U.S. Consumer Product Safety Commission (CPSC) under the Consumer Product Safety Improvement Act and the Federal Hazardous Substances Act.

We might not live in a sustainable age, but we’re living in the age of sustainability. The movement has gained a level of prominence in recent years that is difficult to dispute. The scholarly fields associated with sustainability have expanded dramatically; new tools and methods have appeared that help define, measure, and assess sustainability; and a broad range of organizations and communities have embraced the principles of sustainable living. Sustainability, in fact, has gone from marginal ecological idea to mainstream movement in a surprisingly short amount of time. We now see sustainability publicized at the supermarket, on university campuses, at the aquarium, in corporate headquarters, in government ministries, and in countless other places. A growing number of universities, nongovernmental organizations (NGOs), and corporations in the Western world possess an “office of sustainability”— replete with sustainability plans and guidebooks—but none have an “office of green radicalism” or an “office of the status quo.” In a sense, this environmental discourse has won out over rival conceptions of humanity’s relationship to the natural world. This chapter is an attempt to sketch out the different ways in which sustainability has gained a foothold in contemporary society. It is not meant to suggest that our world is sustainable. On the contrary, many barriers and entrenched interests have kept our world rather unsustainable, and Mathis Wackernagel has even argued that, since the 1990s, we have exceeded the Earth’s capacity to sustain us; we are now living in a state of global overshoot. The goal here, rather, is to show the ways in which our society has constructively responded to our ecological crisis—to demonstrate the growth and elaboration of the sustainability movement and describe some of the successes it has achieved in counteracting our bad habits. As the philosophy of sustainability has developed, so too has it expanded its scope. If we recall from earlier chapters, the concept of sustainability began in the eighteenth century as a method of managing forests, and by the 1960s and 1970s it had become a reaction to industrialism and the trend toward ecological overshoot.