Exposed Science. Sara Shostak. Читать онлайн. Newlib. NEWLIB.NET

Автор: Sara Shostak
Издательство: Ingram
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Жанр произведения: Медицина
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isbn: 9780520955240
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of susceptibility genes offers the potential to reduce the guesswork in risk assessment and therefore it is likely that the ability to issue fair and appropriate regulations concerning human hazards will increase markedly (Olden & Wilson 2000).

      As this statement makes clear, the argument can be “extended” (Snow et al. 1986) to speak to “both sides” of regulatory battles; even though they may disagree about what “fair and appropriate regulation” would look like, industry, activists, and regulators cannot help but agree that it is a worthy goal.

      At the same time, the problem of human genetic variation in response to environmental exposures is a focus of research in environmental genomics and molecular epidemiology that seeks to develop new clinical tools for identifying persons at risk, in addition to providing surveillance, early intervention, or prophylaxis to prevent disease onset. As I detail in the following chapter, NIEHS administrators frame research on genetic susceptibility as an effort to be “responsive to the needs of the American people” (Interview 27), particularly people’s need to understand “Why me?” in the context of illness: “my friend smoked the same number of cigarettes, we worked in the same industry, and why do I [have cancer]?” (Interview S37). The flexibility of the consensus critique is part of its appeal to a wide variety of stakeholders.

      Negotiating Limits

      In contrast to the domains of contentious politics, where such narratives are more frequently put to work to mobilize collective action, environmental health scientists who advocate for molecular genetic and genomic research face a unique challenge. Specifically, they have to make a case for a transforming the practices of environmental health science, without thoroughly undermining extant processes of environmental health research, risk assessment, and regulation. This system remains a critical part of the public health infrastructure and, as shown in Chapter 5, it also is integral to their efforts to validate new, molecular techniques. This challenge also has shaped the particular form and foci of the consensus critique.

      

      Scientists use three primary strategies in seeking to promote molecular genetic and genomic techniques for use in testing and risk assessment without delegitimizing current practices and the regulatory policies that rely on them. First, many statements in favor of new techniques emphasize the new molecular levels of analysis made possible by molecular genetics and genomic techniques, with the goal of “moving beyond classical toxicology” (NCT 2002). The argument here is that, although current toxicology and risk assessment provide the best possible system at what environmental health scientists call the “phenomenological level,” genomics offers an innovative means of conducting toxicological research “down at the molecular level” (Field Notes, NIEHS July 2002). One hoped-for consequence of molecular-level research is that it will illuminate the pathways through which chemicals perturb biological functioning and create toxic effects, as, in the words of a regulatory scientist, “oft times . . . we have no idea in the world how some effect comes about” (Interview P02).7 Thus, scientists claim that that the effects observed at the phenomenological level are real, albeit poorly understood. Similarly, a molecular epidemiologist argued, “Toxicology needs to go beyond kill ’em and count ’em” (Interview S26). This framing of extant practices as both effective and limited is evident also in a paper about toxicogenomics in Science, which described toxicology as both “an imprecise science” and “a time honored way of identifying human health risks” (Lovett 2000: 536).

      Second, advocates of molecular genetic and genomic techniques argue that they will provide a means of doing toxicological risk assessment that is quicker and less expensive and that satisfies the demands of the animal rights movement for reductions in animal testing. This comment implies that, although current testing regimens provide accurate data, they are inadequate for testing “everything that’s out there” (Interview S27). For example, scientists suggest that genomic techniques could be used to set priorities for toxicology testing at the NTP, thereby increasing its efficacy, given limitations in available time and money for testing:

      The Program has always been interested in looking at alternative methods, other short-term tests that might provide indications of risk. These are extremely valuable in screening and prioritizing chemicals. So, for example, if you had 50 chemicals and you could only study 10, which ones would you choose? (Interview S96).

      Framing the potential contribution of new techniques in this way emphasizes the fiscal and social costs of contemporary toxicological techniques, while leaving their scientific validity unscathed.

      Thirdly, scientists emphasize the possibility that molecular genetic and genomic techniques will expand the range of applications of environmental health research. For example, while acknowledging the traditional relationship between environmental health science and environmental regulation, some environmental health scientists frame gene-environment interaction as a means of also developing a range of behavioral and clinical interventions that could improve public health. Advocacy for “a more biomedical environmental health” (Interview S20), which integrates “lifestyle prescriptions” to minimize the risks of exposure or new pharmaceutical interventions to prevent harmful consequences of exposure (Olden, Guthrie, & Newton 2001), does not impugn the current regulatory regime. Rather, it points to a different approach entirely.

      Only rarely, and always “off the record,” would an environmental health scientist offer an unequivocal critique of risk assessment. For example, this scientist stated: “Risk assessment to me is a black box nightmare. They’re making very important decisions based on very limited information. They have a legal obligation to make decisions. But the data is just terrible. So, there is real temptation to use new approaches, because anything is better than nothing, which is what they have now” (Field Notes 2002). Another scientist commented: “Risk assessment is where magic happens, and you have to be careful when you go there . . . . The fact that somebody does some science doesn’t make risk assessment less magic” (Field Notes 2001).

      More often, using limited frames, proponents of molecular genetics and genomics have been able to promote molecular genetic and genomic technologies as a means of improving toxicology and risk assessment, without discrediting current techniques and standards. This has been critical both to maintaining the legitimacy of the NIEHS, the NTP, and the regulatory system that their research supports and, related, to bringing to the table a wide variety of stakeholders in risk assessment and regulation.

      

      THE MULTIPLE MEANINGS OF GENE-ENVIRONMENT INTERACTION

      The interpretive flexibility of the consensus critique has also played an important role in these processes. The consensus critique states that there are limitations to current methods within the environmental health sciences and proposes that molecular genetic techniques offer a way of improving the reliability and validity of environmental health research. However, it never specifies techniques, nor does it offer a precise operational definition of gene-environment interaction. Because gene-environment interaction therefore can encompass a wide range of research foci and techniques, its advocates have been able to garner the support of scientists with disparate research agendas and commitments.

      Gene-environment interaction has multiple meanings, which have been shaped by the specific organizational contexts and intellectual lineages of environmental health scientists.8 To begin, some scientists define gene-environment interaction as the study of the inherited individual and subpopulation genetic susceptibilities that make some people more vulnerable than others to being harmed by environmental exposures. For example, speaking at a meeting of environmental health and justice activists in New York City in 2002, Samuel Wilson, then the Deputy Director of the NIEHS, explained:

      Genes controlling responses to environmental factors have variations in their DNA sequences. That’s just a fact that we’ve begun to appreciate. We see that there are variations. There are many examples where a combination of an exposure and a gene variant are required for an adverse health effect. This is the gene-environment interaction concept (Field Notes 2002).

      The identification of individuals and subpopulations that are genetically susceptible to the effects of environmental exposures is a relatively new goal for the environmental health sciences. Toxicologists often explained this