Packaging- and Ingredient-Related Green Knowledge and Green Service Behavior of Sales Employees in Thai Cosmetic Retail: Empirical Evidence from a Nationwide Survey

The global cosmetic retail industry is under mounting pressure from consumers and regulators to substantiate environmental claims and to prevent greenwashing at the point of sale. This study examines the relationships between two dimensions of sales employees' green knowledge—Green Packaging Knowledge (GPK) and Green Ingredient Knowledge (GIK)—and their Green Service Behavior (GSB) in the Thai cosmetic retail sector. Guided by the Theory of Planned Behavior, a quantitative cross-sectional survey was conducted with 245 frontline sales employees of a major Thai cosmetic retail brand, selected through proportional quota sampling across five regions. Data were collected with a validated questionnaire (Cronbach's alpha = .92–.95) and analyzed using descriptive statistics, one-way ANOVA, and Pearson's product-moment correlation. Results showed high overall levels of GPK (M = 3.68), GIK (M = 3.63), and GSB (M = 3.67), with the weakest items concerning recycling-symbol interpretation and greenwashing-risk awareness. Personal factors (age, education, and tenure) produced no statistically significant differences in GSB (p > .05). In contrast, GPK was positively and strongly correlated with GSB (r = .655, p < .01), and GIK showed a very strong positive correlation with GSB (r = .830, p < .01). The findings indicate that specialized, verifiable green knowledge—rather than demographic characteristics or accumulated tenure—is the key correlate of high-quality green service delivery. Implications include targeted evidence-based training, knowledge-support systems at the point of sale, and transparent communication protocols that reduce greenwashing risk and strengthen customer trust in cosmetic retail.