Health literacy and environmental health behaviors in the context of microplastic exposure: a cross-sectional study in rural Thailand

Abstract Microplastic contamination has emerged as a growing environmental exposure concern in river-dependent rural populations, yet evidence on behavioral determinants remains limited. Health literacy is a key upstream determinant that may influence risk perception and preventive behavioral responses. This study examined the association between health literacy and preventive behaviors related to microplastic exposure among residents living along the Mun River in Buriram Province, Thailand. A community-based cross-sectional study was conducted among 268 adults selected using multistage sampling. Data were collected through structured interviewer-administered questionnaires. Health literacy was operationalized as a multidimensional construct covering six domains and categorized into sufficient and insufficient levels. Preventive behaviors were dichotomized as good or poor based on predefined scoring criteria. Multivariable logistic regression models were applied to estimate adjusted associations between health literacy and preventive behaviors while controlling for potential confounders, including sociodemographic and behavioral factors. Adjusted odds ratios (AORs) with 95% confidence intervals (CIs) were reported. Insufficient health literacy was highly prevalent (70.9%) and was independently associated with poor preventive behaviors (AOR = 6.05, 95% CI: 3.08–11.90, p < 0.001) after adjustment for covariates. Domain-specific analysis identified action literacy (AOR = 2.67, 95% CI: 1.29–5.59, p = 0.008) and appraisal literacy (AOR = 3.19, 95% CI: 1.51–6.73, p = 0.002) as significant predictors. Frequent fish consumption was also independently associated with poor preventive behaviors (AOR = 3.25, 95% CI: 1.35–7.84, p = 0.009). Health literacy is a strong independent correlate of preventive behaviors related to microplastic exposure in rural riverine populations. Findings support targeted, domain-specific health literacy interventions—particularly action- and appraisal-oriented competencies—as a public health strategy to reduce environmental exposure risk.