Is the public really concerned about microplastics? The importance of measuring everyday relevance and behavioral intentions as well as stated concern

Recent studies suggest that the European public is concerned about the impact of microplastics on environmental and human health. However, concern is usually measured by asking people relatively simple questions about their current levels (i.e., stated concern) with responses potentially inflated by immediate contextual salience, raising questions about interpretability. To explore this issue, we conducted a cross-sectional random-quota survey of German ( n =1,135) and Italian ( n =1,124) citizens, asking them not just about stated microplastics concern but also more indirect indicators of concern including the extent to which they think about and discuss microplastics in their everyday lives (everyday relevance) and intend to reduce their own exposure (behavioral intentions). Further, we explored the degree to which awareness and knowledge about microplastics differed across countries as well as across key demographics and how different indicators of concern were associated with these factors. Replicating earlier work, awareness was lower in Italy compared to Germany, and stated concern was high overall. In addition, most people reported thinking or talking about microplastics only rarely or sometimes, but still tended to say they were likely to engage in behaviors to reduce exposure. Moreover, stated concern and everyday relevance both mediated the degree to which microplastics knowledge predicted these behavioral intentions. The results paint a nuanced picture of public microplastics concern and support arguments for including multiple metrics including everyday relevance and behavioral intentions. They also highlight the potential of increasing public knowledge given positive associations with all three metrics. In conclusion, even if they are not particularly salient in everyday thoughts or discussions, microplastics do appear to concern many German and Italian citizens and future studies should investigate the causal chain of knowledge, awareness, concern, and action more directly. • Cross-national survey assessed multiple indicators of microplastics concerns. • Microplastics awareness was lower in Italy compared to Germany. • Stated concern about effects was higher for environmental compared to human health. • Tendency to think and talk about microplastics was lower than stating concern. • Microplastics knowledge predicted behavioral intentions via concern and relevance.