Toxic Entanglements. A Situated Analysis of Epigenetic Knowledge Production in Environmental Toxicology

Sola dosis facit venenum – »Alle Dinge sind Gift, und nichts ist ohne Gift; allein die Dosis machts, daß ein Ding kein Gift sei.« (Paracelsus 1538, the ‘father’ of toxicology)

The longstanding dogma of toxicology »the dose makes the poison« has been subject to renegotiation in recent years, triggered by new insights from the molecular biological field of epigenetics. Epigenetics investigates how small chemical modifications upon the DNA (epi-, Greek: »upon«) can have a lasting effect on gene expression without being caused by genetic mutations. Novel research findings show that such epigenetic modifications have been found to change in response to environmental stimuli – such as toxins, nutrition or stress – giving rise to research approaches summarized as environmental epigenetics.

For the field of environmental toxicology, acknowledging the role of the environment in disease development via epigenetic mechanisms is something very appealing. Studies in this field investigate the harmful effects of environmental toxins, such as plasticisers or metals, on organisms. However, scientists have been puzzled for decades by the mechanism behind the long-term health effects of toxins that could not be explained by mutations. To answer this longstanding question, research in the field is currently highly invested in unravelling the basic mechanism by which toxins affect epigenetic processes in the body and how these changes can cause later life diseases.

In my dissertation project, I would like to address the following research question: what does the approach of environmental epigenetics make in-/visible in environmental toxicology and with what consequences? I am particularly interested in the shift of environmental toxicology towards adopting and adapting epigenetic approaches to their research agendas. I see this shift embedded in the ongoing process of the molecularization of the life sciences since the 1990s, drawing special attention to the fields of toxicology and environmental epidemiology. The fields current efforts to trace the long-term effects of toxic exposure back to the materiality of the molecular reflects this reorganization of the field towards a »molecular ‘style of thought’« (Fleck, 1979; Rose, 2007).

I want to illustrate this shift by focusing on the object of toxicity. How does toxicity come into being as a »recognizable object« (Murphy 2006) via contingent moments in the history of toxicology and environmental epidemiology? In what ways changes the object of toxicity in relation to the transformation of the field from a descriptive, service-science oriented science towards a mechanistic science, adapting molecular biology tools? What novel regimes of evidence are implemented to make toxicity visible? Where can we see frictions towards the classical toxicology and epidemiology? Drawing on literature analysis, qualitative interviews and participant observation, I ask myself how researchers think as well as do toxicity in their specific research contexts leading me ultimately to the questions of how toxicity is »made to matter« (Murphy 2006) in environmental epigenetic research on toxins and with what consequences for the perception of health and disease.

The PhD project is embedded in the project “Situating Environmental Epigenetics. A Comparative, Actor-Centered Study of Environmental Epigenetics as an Emergent Research Approach in Three Research Fields”, funded by the by the German Research Foundation and led by Prof. Ruth Müller.