Associations between individual and environmental factors and adolescent substance use in the border regions of the Netherlands, Belgium, and Germany.

INTRODUCTION: Adolescent use of alcohol, tobacco, and cannabis remains a significant public health concern across Europe. In border regions, young people may be exposed to differing laws, social norms, and environmental influences, creating a context in which individual and environmental associations may operate differently. This study investigates how individual and environmental factors relate to substance use among adolescents in the border regions of the Netherlands, Belgium, and Germany. METHODS: The study included 20,461 adolescents (aged 13-17) from the cross-border regions of the Netherlands, Belgium, and Germany. In 2023, they completed a standardized, anonymous online questionnaire during school hours. The questionnaire assessed substance use (alcohol, tobacco, cannabis), psychosocial characteristics, and physical, social, and economic environmental factors and was analysed using descriptive statistics and logistic regression. RESULTS: Higher odds of binge drinking, smoking and vaping, and cannabis use were observed for older age, peer influence, and frequent late-night outings, while lower odds were observed for parental monitoring, clear household rules, and structured leisure. While the strength of these associations varied across countries, the underlying factors were largely consistent. CONCLUSION: Behavioral differences between countries may reflect variations in national policies and cultural contexts, as well as the broader social dynamics that characterize life in cross-border regions. The social and cultural environments in which adolescents grow up appear to be more decisive. Effective prevention in border regions should therefore prioritize context-specific, cross-border collaboration, focusing on strengthening social structures around parents, schools, and leisure time.