Precise Yet Uncertain: Broadening Understandings of Uncertainty and Policy in the BPA Controversy.

Bisphenol A (BPA) is one of the most studied and most controversial chemicals used by the food packaging industry, because of its endocrine disruptive properties. Part of the controversy is due to the uncertainty that surrounds the effects of BPA on the endocrine system. Uncertainty includes data gaps, methodological hurdles, incompatibilities between toxicology and endocrinology-based approaches, and so on. In this article, we analyze how uncertainty has been conceptualized and treated. We focus on the European Food Safety Authority assessments of BPA, and study how exposure and hazard assessments have evolved over time, how uncertainty has been analyzed, and how the agency responded to controversies. Results show that in the attempt to reduce knowledge gaps, assessments have become progressively larger, including more references, evidence, and effects. There is a tendency toward greater precisions and specification of results, and toward protocolization of all processes included in the assessment (from literature review, to uncertainty assessments, and public consultation). Yet, the uncertainty has not diminished following the increase in evidence. We argue that the strategy used to reduce uncertainty within risk assessment, namely including more variables, studies, data, and methods, amplifies the uncertainty linked to indeterminacy (as more results increase the fragmentation of the knowledge base due to the open-ended nature of complex issues) and ambiguity (as complexity gives way to multiple nonequivalent interpretations of results). For this reason, it is important to consider different types of uncertainty and how these uncertainties interact with each other.

Isolated yet open: A metabolic analysis of Menorca.

Small islands are vulnerable to climate change, and at the same time contribute to local and global environmental problems with the intensification of tourist activities. Whereas there are many studies on the resource requirements or environmental impacts of small islands, there are few efforts to integrate information that is often analysed separately. Metabolic analysis, beyond quantifying biophysical flows, studies how society transforms these flows to reproduce the identity of the whole. This study applies the Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM) approach, to analyse the environmental and economic performance of different economic activities in the Mediterranean island of Menorca (Spain). The openness of the metabolic system (observed in the dependence on imports) and externalization of environmental impact are illustrated using the examples of the cheese and tourist industry. The results show that a higher economic performance in terms of value added is associated with activities in industry and services with a larger dependence on imports of "external resources" - fuel for transportation, milk for cheese, seasonal workers and "paying capacity" of tourists. This dependence reduces local environmental pressures and also adaptation capacity, since decisions made in Menorca may have limited impact elsewhere. Local agriculture depends less on external resources but it is limited by the low economic productivity of land and labour. An integrated analysis of the relations between metabolic rates and densities of flows in the different compartments of the society provides a holistic picture of sustainability issues and can contribute to decision-making by avoiding partial information.