Are climate change perceptions related with plastic policy support? Effects of climate change skepticism, guilt, and efficacy on the acceptance of the plastic tax

PLOS One | https://doi.org/10.1371/journal.pone.0337327 December 29, 2025 23 / 30 Results and summery The negative effects of climate change are a current cause for concern, rather than a future issue. In addition, the convenience of consumption exacerbates the problem of climate change. In particular, the unconscious use of plastics has emerged as a leading cause of the increase in greenhouse gases, emphasizing the urgent need to regulate plastics. Thus, introducing a plastic tax is essential; however, the acceptability of the tax seems to hinder its implementation. This study analyzed the deter- minants of the decision to pay a tax to reduce plastic use by setting the planned behavior factors such as climate change skepti- cism, guilt, and efficacy as predictor and moderating variables. The main findings of this study are summarized as follows. First, in terms of value factors, environmentalism, altruism, and egalitarianism had a significantly positive effect on the support for the plastic tax, whereas materialism had a significantly negative effect. In addition, in the risk perception paradigm, perceived risk, knowledge, and trust had significantly positive effects on the support for the tax. Regarding the planned behavior factors, climate change skepticism, guilt, and efficacy had significant effects on the support for the plas- tic tax, with climate change skepticism demonstrating a negative effect and guilt and efficacy showing a positive effect. The explanatory power of the variables in the factors mentioned above increased in the order of perceived risk > climate

change skepticism > government trust > environmentalism > knowledge > egalitarianism > altruism > guilt > efficacy > material- ism, suggesting that perceived risk plays a crucial role in the support for the plastic tax. This study examined the interaction effects of value and risk perception paradigm factors with the environmental psychological factors of climate change skepticism, guilt, and efficacy as moderating variables. The results showed that climate change skepticism interacted with materialism and emotion, and guilt interacted with environmentalism, altruism, egalitarianism, and perceived risk. Finally, we found that efficacy interacted with altruism and perceived risk. In particular, when analyzing the effects of personal values and risk perception paradigm factors on the support for the tax, we found that planned behavior acted as a moderating variable. Based on the above results, among the 11 hypotheses, environmentalism (Hypothesis 1), altruism (Hypothesis 2), egalitarianism (Hypothesis 3), materialism (Hypothesis 4), perceived risk (Hypothesis 5), knowledge (Hypothesis 6), trust (Hypothesis 7), and emotion (Hypothesis 8) were accepted, and emotion hypothesis was rejected. In addition, the mod- erating effect of climate change skepticism (Hypothesis 9) on materialism and emotion was partially accepted, that of guilt (Hypothesis 10) on environmentalism, altruism, egalitarianism, and perceived risk was partially accepted, and that of efficacy (Hypothesis 11) on altruism and perceived risk was partially accepted. Discussion and implications

We analyzed factors determining plastic tax support, focusing on willingness to pay rather than tax amount, finding that values, risk perception, and planned behavior factors determine support for plastic taxes. Our study demonstrates that effective plastic tax policies must simultaneously address values, risk perceptions, and planned behavior elements. This integrated approach aligns with van der Werff et al. [110], who showed environmental policies succeed when addressing both motivational and implementation factors. However, balancing these factors faces challenges from potential conflicts. Gifford [111] notes that policies targeting rational risk assessments may clash with deeply held values, while Steg et al. [112] emphasize that behavioral control interventions can be ineffective if underlying values are unaddressed. Additionally, Harring et al. [113] demonstrate that policies focusing on economic incentives may undermine intrinsic environmental motivations if perceived as coercive. Theoretical insights Our findings provide theoretical insights into plastic tax acceptance mechanisms. The strong predictive power of perceived risk (β = .161) supports psychometric paradigm assertions that subjective risk evaluations drive policy preferences more than objective assessments [108], extending Kahan et al.‘s [24] work on motivated reasoning where individuals process climate information through value-laden filters.