Results

- Toxicology as a nanoscience? – Disciplinary identities reconsidered

Following a historic overview at knowledge-production in toxicology, we will present our views on disciplinary identity formation in toxicology through a discussion of citations from our interviews.

 

In this chapter, we will give a historical overview at the development of toxicology and its three-phase transformation into a scientific discipline. Furthermore, we will focus on the specific methods and practices with which toxicological knowledge-production enters the nano-sciences. Selected quotations from our interviews will be used to illustrate how toxicological identity formation is challenged by the cooccurrence of a previous, historically grown technical self-understanding (thought style) as well as the new requirements of participating in the nano-sciences.

Traditionally, toxicology examines the potentially harmful effects of chemical or physical agents for biological systems. It is also called the science of the poisons [40]. During its transformation into a scientific discipline, toxicology went through three phases: In the first phase, the health effects of selected substances were observed. First, toxicologists wrote down a phenomenology of poisons and remedies. The roots of such phenomenologies of poison can be retraced in the origins of the development of human medicine. In antique European, Arabic and Asian cultures, knowledge of toxic substances was inseparably linked with medical training and practice [40]. Furthermore, the science of toxin was closely linked to botany and the plant sciences in ancient Greece. Theophrastus, a pupil of Aristotle (372-287 BC) composed botanical works and gave detailed descriptions of medicinal and poisonous plants. His work has been designated as the beginning of modern botanies. Arab cultures developed chemical approaches in toxicology. In the Middle Ages, mainly southern European physicists like Maimonides (1135–1204) and Pietro de Abano (1250–1316) contributed to the identification of poisons [40].

A second phase covered the experimental approaches, used to examine the mechanisms of dose effect dependence. Paracelsus (1493–1541) is considered the founder of this phase. In the 16th century he developed a concept of poison, which is still applicable today. He thereby initiated a turn away from a merely descriptive analysis of phenomena and the categorizations and listing of poisons then found in experimental and analytic research approaches. Furthermore, he began to use his knowledge for therapeutic applications, that is, he used 'poisons' for beneficial effects. The knowledge gained in a variety of scientific and medical disciplines supported the transformation of toxicology in the 18th and 19th centuries from knowledge-production based on experience into a concept-based scientific field [41]. In the early 20th century, toxicology was established as a natural scientific discipline clearly demarcated from pharmacology, medicine, chemistry and biology [40]. In a third phase, toxicology increased in relevance through its emergence as a testing discipline and attendant research science. This happened in the second half of the 20^th century in the context of intensive scientific and technological growth, accompanied by hazardous incidents and social controversies. Through the development of guiding principles for the regulation of toxic chemicals, work place safety and public health, toxicological knowledge became useful for politics and policy-making in various industrial nations. With its knowledge of the health and environmental effects of new materials and substances, based on quantitative laboratory studies, toxicology developed a comprehensive network for the measurement and categorization of the dose-effect-dependence of the most prominent industrially used materials. The investigation of the toxicity of particles is closely linked historically to mineral fibers like asbestos and industrial activities, like coal mining. Thus, the European community for steel and coal (ECSC) contributed to the establishment of the research field of particle toxicology [42]. By developing concrete, measurable testimony about risk and safety, toxicology established itself as an attendant, testing discipline and monitorial authority. They are cover the identification, quantification and prevention of the unfavorable side-effects of chemicals. In addition, safety regulations for job descriptions, and tolerance limits for chemical additives in food and water were determined [43]. Hence, as one interview partner holds, toxicology became dependent on industry and politics. Toxicology needs research funds from industry and politics, which in turn need applicable toxicological knowledge.

"For politics and industry our research is absolutely relevant and necessary. Therefore we need their support." (Toxicologist II, German research center)

Knowledge-production within toxicology mainly focuses on quantitative in-vitro and in-vivo studies [44]. In-vitro studies cover laboratory studies of cell lines which are specially bred under variable conditions. In-vivo studies focus on the reaction of the organism as a whole to the admission of and exposure to certain substances. They mainly involve animal tests with conventionally bred or transgenic rodents in the laboratory and, to a more modest extent, clinical trials with humans, as a researcher at a Swiss university, working in the field of inhalation toxicology, holds:

"Our possibilities to conduct studies with humans are extremely limited. Therefore, we try to develop models. In-vivo, I have been working with small rodents, like rats and hamsters. Recently, I have also started to work with mice. In particular, I use transgenic mice, which I consider a very good model for specific questions. With the second model we are trying to reconstruct respiratory epithelia in- vitro, in order to observe particle-lung interactions." (Biologist II, Swiss university)

Toxicology represents an interdisciplinary research field. It uses up-to-date methods and techniques, which overlap with neighboring disciplines like chemistry, pharmacy and medicine. Since the 1990s it has also become involved in the field of molecular biology. At the same time, it underwent a paradigm-shift in its research practice from high to deep dosages [45]. In the opinion of several toxicologists, particularly in Europe, toxicology's interdisciplinary character is a crucial precondition for doing research on particles at the nano-scale level:

"We work together with the material sciences, with chemists, physicists and engineers. Furthermore, the topic is connected with meteorology and thermodynamics. In toxicology, the spectrum is even broader. The classical toxicologist is usually a biologist, biochemist, bio-physicist, pharmacist or bio-engineer. And epidemiology goes together with pure mathematics, particularly in the case of statisticians and epidemiologists, who have a medical or a scientific background, for example physics or chemistry, but primarily medicine." (Toxicologist I, German research center)