Using a new visualization tool and combining field and experimental designs, the paper in Science of the Total Environment suggests that although bottled and tap water consumer groups differ greatly in their beliefs, perceived health risks and taste, these differences seem to reflect illusionary beliefs rather than actual experiences or product characteristics.

Despite the rigorous control of tap water quality, substantial price differences, and environmental concerns, bottled water consumption has increased in recent decades. To facilitate healthy and sustainable consumer choices, a deeper understanding of this ‘water consumption paradox’ is needed. The two consumer groups showed “polarized” ratings regarding perceived quality/hygiene, health risks and taste for bottled and tap water, indicating that the two consumer groups substantially diverged in their beliefs. However, in the blind taste test, neither consumer group were not able to distinguish tap from bottled water samples (consumer perspective). Moreover, tap or bottled water samples did not systemically vary in their ascribed health-risk or taste characteristics (product perspective).. Public health campaigns should address these illusions to promote healthy and sustainable consumer choices. The work is part of the DFG Forschergruppe Riskdynamics and the SFB/Transregio 161.