From the laboratories of toxicologists, Edges of Exposure by Noémi Tousignant offers an account of the technical and infrastructural limits to understanding toxicity in post-colonial Senegal. Despite a growing body of literature in the humanities and the social sciences on toxicity, there remains a particular need to understand the embodied toxic geographies of the Global South. Although these regions have long been noted as the “dumping ground” of more affluent economies, the precise distributions and consequences of toxicities outside the Euro-Atlantic north, though seemingly dire, remain largely unknown.
This dearth of scientific evidence makes toxicity a frustratingly slippery object of ethnographic inquiry. Trails of toxicity are hard to follow, and toxic publics remain inchoate or nonexistent. In her book, Tousignant tackles this methodological problem by focusing on the vocational practice of Senegalese toxicologists, who have confronted this very dilemma in their daily scientific pursuits. Her research traces historical records and memories of toxicologists in the post-independence period of the 1960s–1980s, a period when their work remained deeply entangled with Senegal’s former colonizer, France. Nonetheless, their scientific biographies offer glimpses of an era of inventive, civic toxicology and its “promises of mobility, autonomy, and equivalence for African science that were sustained by public (national and international) funding for science, by nationalist political rhetoric, and by educational policies” (p. 61). Such aspirations ended abruptly with economic crisis in the 1970s and subsequent liberalizing reforms that cut public funding for scientific research and other public services (p. 13). Extending her historical analysis to the craft of contemporary toxicologists, who operate within and despite severe structural impediments, Tousignant works to understand what capacities are required to emerge from pervasive states of toxic “unprotection” that define the present moment (p. 16). If toxicity exists as a defining, durative, but continuously under-recognized harm of late-industrialism, especially in post-colonial/neo-imperial realities, what institutional capacities––resources, techniques, and commitments––are needed to quantify this problem, and offer protections, at the scale of the population?
Throughout Edges of Exposure, Tousignant draws our attention to this concrete problem of capacity, persistently faced by toxicologists operating in Senegal’s post-colonial context. She follows them in the process of “working, succeeding, and failing to gain, keep, and stretch the material and institutional capacity needed to detect and define toxic risks in the country” (p. 4). Among the particularly innovative aspects of the book is Tousignant’s methodological treatment of laboratory equipment, substances, and techniques, whose various states of decay she uses to probe the “rhythms” (p. 20) of toxicological research capacity across time. Laboratory conditions reflect the global and local dynamics that partially enable but ultimately inhibit protective toxicology in Senegal’s present. Fleeting periods of abundant resources, and the professional mobility of Senegalese scientists, Tousignant finds, depended on the vicissitudes of intersecting interests with foreign institutions and actors from the Global North. Places like Senegal, we learn, are not envisaged by transnational funders and collaborators as centers of methodological innovation, despite earlier periods when they performed exactly that. Instead, Senegal now offers unique sites of sampling conditions to investigate health concerns of better-equipped foreign partners (such as contaminated food exports and the ecological impacts of pesticides in tropical climates). Thus, recent toxicological research in Senegal reflects global health priorities, rather than those that might best build capacities for enacting national protective measures. The current material state of laboratories contains a historical record of such uneven alliances and also implies the stubborn persistence of (neo)colonial relations and dependencies. Missing reagents, dysfunctional equipment, and derelict materials “index a loss of skill and memory” (p. 43) and a “slow ruination” (pp. 50–53) of the capacities needed to maintain ongoing, meaningful toxicological assessments.
Yet, this narrative of loss also conjures stories of incremental advancement, the maintenance of capacities, pathways for scientific careers, and imaginations of an innovative national toxicology. While Tousignant argues that the fragmentary capabilities of toxicologists, and the limited purview their research constitute a “fiction” of capacity and regulation, she contends that this fiction is nonetheless a productive one (p. 87). Furthermore, the decaying remains of past techno-infrastructural investments nonetheless enable some research continuities. While the limited means of these toxicologists cannot possibly approach the regulatory scale of the state, by assuming its responsibilities, their work calls on a “protective and provisioning” state, absent for duty (p. 104). Thus, however enfeebled by structural conditions, we can understand such pursuits of knowledge beyond their evidentiary power. Toxicologists’ acts of public service also constitute a politics of “not waiting” (p. 135) for the state, however needed state resources are for the robust provisioning of scientific resources.
Tousignant’s contribution to theoretical discussions in medical anthropology, post-colonial studies, and STS are artfully woven throughout the book and highlight the broad-ranging appeal her study will have to scholars in these disciplines. The innovative methodological approach of her book, using a lab study to examine post-colonial epistemic and health inequalities, might also limit its appeal for certain readers. In the epilogue, Tousignant discusses the frequent criticism her work has received because it does not encompass more perspectives, particularly the activism of exposed communities. While toxic crises (including the lead-poisoning deaths within the community of Ngagne Diaw) elicit moments of intense public scrutiny, a focus on such ephemeral political moments would, she contends, belie how “contamination and exposure have been most visible in, and indeed made visible by, toxicologists’ work” (p. 144).
In other words, Tousignant’s work demands that we focus on what would actually be necessary to equip a nation to anticipate, and thus protect against, a toxic event so that it never emerges as a public health crisis at all. While I am sympathetic to this methodological choice, the book can seem insular in its perspective as a result. I am left wondering about what restricted toxicologists’ engagements with the people most burdened by toxic exposures, and why they did not seek out a wider public to receive, and thus care about, their work. Tousignant’s request that we remain focused on these toxicologists, however frustrating it becomes to observe the constant marginalization of their work, is perhaps a crucial insistence. Ultimately, their tribulations point us to what limits our contemporary political imagination, such that toxic protections remain a “luxury” rather than a necessity for restoring environmental health justice throughout the world.