Sandrine Blanchemanche

The public understanding of nanotechnology in the food domain: The hidden role of views on science, technology, and nature

In spite of great expectations about the potential of nanotechnology, this study shows that people are rather ambiguous and pessimistic about nanotechnology applications in the food domain. Our findings are drawn from a survey of public perceptions about nanotechnology food and nanotechnology food packaging (N = 752). Multinomial logistic regression analyses further reveal that knowledge about food risks and nanotechnology significantly influences people’s views about nanotechnology food packaging. However, knowledge variables were unrelated to support for nanofood, suggesting that an increase in people’s knowledge might not be sufficient to bridge the gap between the excitement some business leaders in the food sector have and the restraint of the public. Additionally, opposition to nanofood was not related to the use of heuristics but to trust in governmental agencies. Furthermore, the results indicate that public perceptions of nanoscience in the food domain significantly relate to views on science, technology, and nature.

Use of advanced cluster analysis to characterize fish consumption patterns and methylmercury dietary exposures from fish and other sea foods among pregnant women

On account of the interspecies variability in contamination and nutrient contents, consumers must balance the risks and benefits of fish consumption through their choice of species, meal size and frequency. The objectives of this study were to better characterize the risk of methylmercury (MeHg) exposure in a sample of 161 French pregnant women consuming sea food, including fish, molluscs and crustaceans, and to explore the use of unsupervised statistical learning as an advanced type of cluster analysis to identify patterns of fish consumption that could predict exposure to MeHg and the coverage of the Recommended Daily Allowance for n-3 polyunsaturated fatty acid (PUFA). The proportion of about 5% of pregnant women exposed at levels higher than the tolerable weekly intake for MeHg is similar to that observed among women of childbearing age in earlier French studies. At the same time, only about 50% of the women reached the recommended intake of 500 mg/day n-3 PUFA. Cluster analysis of the fish consumption showed that they could be grouped in five major clusters that are largely predictable of the intake of both MeHg and n-3 PUFA. This study shows that a global increase in seafood consumption could lead to MeHg exposure above the toxicological limits for pregnant women, thereby questioning the overall balance between this potential risk and potential beneficial effects of n-3 PUFA intakes. Only pregnant women consuming a high proportion of fatty fish meet the n-3 PUFA intake requirements without exceeding the toxicological limit for MeHg. The clusters identified suggest that different intervention strategies may be needed to address the dual purpose of ensuring high PUFA intakes at acceptable MeHg exposures.

The Combination of Lab and Field Experiments for Benefit-Cost Analysis

This article explores the combination of laboratory and field experiments in defining a welfare framework and the impact of different regulatory tools on consumer behaviors. First, an overview of strengths and weaknesses raised by the experimental literature show that, for food consumption, lab and field experiments may be complementary to each other. The lab experiment elicits willingness to pay useful for determining per-unit damages based on well-informed, thoughtful preferences, while the field experiment determines purchase/consumption reactions in real contexts. Second, the analytical approach suggests how to combine the results of both lab and field experiments to determine the welfare impact of different regulatory tools such as labels and/or taxes. Third, an empirical application focuses on a lab and a field experiment conducted in France to evaluate the impact of regulation on fish consumption. Estimations for the French tuna market show that a per-unit tax on tuna and/or an advisory policy lead to welfare improvements.

Balancing the risk of dioxins and polychlorinated biphenyls (PCBs) and the benefit of long-chain polyunsaturated fatty acids of the n-3 variety for French fish consumers in western coastal areas.

A study of 401 fish-eating adults living in a coastal region of France was undertaken to establish exposure to dioxins/polychlorinated biphenyls and the intake of long-chain polyunsaturated fatty acids of the n-3 variety. Fish consumption was estimated using food frequency diaries and the dioxin/polychlorinated biphenyl data collected by the French control authorities was used to calculate dietary exposure. The results showed that for a group of adult subjects selected because of their consumption of fish, 60% achieved the nutritional recommendation for long-chain n-3 polyunsaturated fatty acids and 79% were exposed to total dioxins below the toxicological threshold of 14 pg kg−1 body weight week−1. Nevertheless, only 41% of these subjects had an optimal balance between the risk and benefit of eating fish, because 19% were meeting the nutritional recommendation but exceeding the toxicological threshold, whereas 38% were exposed below the toxicological threshold but failed to reach the recommended intake of long-chain n-3 polyunsaturated fatty acids. Similar results were found regarding the balance between long-chain n-3 polyunsaturated fatty acids and polychlorinated biphenyls even if a toxicological threshold was not established for these compounds. The results show that meeting the nutritional requirements of 0.5 mg day−1 of long-chain n-3 polyunsaturated fatty acids is compatible with respect to toxicological thresholds, while an intake higher than 1.5 g day−1 is likely to lead to a dietary exposure above the provisional tolerable weekly intake for dioxins.

Dissemination of Health Information within Social Networks

In this paper, we investigate, how information about a common food born health hazard, known as Campylobacter, spreads once it was delivered to a random sample of individuals in France. The central question addressed here is how individual characteristics and the various aspects of social network influence the spread of information. A key claim of our paper is that information diffusion processes occur in a patterned network of social ties of heterogeneous actors. Our percolation models show that the characteristics of the recipients of the information matter as much if not more than the characteristics of the sender of the information in deciding whether the information will be transmitted through a particular tie. We also found that at least for this particular advisory, it is not the perceived need of the recipients for the information that matters but their general interest in the topic.

Enlisting Supervised Machine Learning in Mapping Scientific Uncertainty Expressed in Food Risk Analysis

Recently, both sociology of science and policy research have shown increased interest in scientific uncertainty. To contribute to these debates and create an empirical measure of scientific uncertainty, we inductively devised two systems of classification or ontologies to describe scientific uncertainty in a large corpus of food safety risk assessments with the help of machine learning (ML). We ask three questions: (1) Can we use ML to assist with coding complex documents such as food safety risk assessments on a difficult topic like scientific uncertainty? (2) Can we assess using ML the quality of the ontologies we devised? (3) And, finally, does the quality of our ontologies depend on social factors? We found that ML can do surprisingly well in its simplest form identifying complex meanings, and it does not benefit from adding certain types of complexity to the analysis. Our ML experiments show that in one ontology which is a simple typology, against expectations, semantic opposites attract each other and support the taxonomic structure of the other. And finally, we found some evidence that institutional factors do influence how well our taxonomy of uncertainty performs, but its ability to capture meaning does not vary greatly across the time, institutional context, and cultures we investigated.

Multiple equilibria with a multiple price list

A multiple price list is useful for eliciting a Willingness-to-Pay (WTP) and a possible Lower Limit (LL) under which the demand is zero. This multiple price list implies an aggregate demand determined by the number of participants whose WTP is greater than the market price and whose LL is below this market price. From a survey focusing on meat demand, we show that this aggregate demand leads to multiple price equilibria.