ASSOCIATION BETWEEN GREEN AND BLUE SPACE EXPOSURE AND BEHAVIOUR PROBLEMS AMONG ADOLESCENTS

Abstract

Abstract: Context: Adolescence is a critical stage of development, marked by emotional, cognitive, and social changes that can predispose individuals to behavioural problems, such as hyperactivity, inattention, relationship difficulties, and conduct problems. These problems compromise well-being and can extend into adulthood. Exposure to natural spaces, particularly green and blue spaces, has been shown to be beneficial to mental health, but its specific role in adolescent behaviour remains largely unexplored. The aim of this study was to assess whether exposure to green and blue spaces is associated with a lower prevalence of behavioural problems in adolescents. Methods: This study was based on a representative sample of 703 adolescents in grades 9 to 12 from the municipalities of Barcelos and Esposende in northern Portugal, assessed in 2025. Behavioural problems were measured using the Portuguese version of the Strengths and Difficulties Questionnaire (SDQ-Por), which has a global scale and five subscales: emotional symptoms; conduct problems; hyperactivity/attention deficit; peer relationship problems; prosocial behaviours. Exposure was analysed in three contexts - home, school and public - considering availability, perceived quality, and frequency and duration of use. Associations were estimated using multilevel regression models adjusted for sociodemographic factors. Results: The mean age of the sample was 16.0 years. More than half of the participants were female (58.0%), and 12.2% of adolescents had abnormal scores on the SDQ-Por scale, with differences between subscales. Adolescents who spent time in domestic green spaces had better overall SDQ scores and fewer problems with conduct, hyperactivity/inattention, and peer relationships, while the use of blue spaces only showed a protective association in peer relationships. No statistically significant associations were observed between the frequency or duration of visits to public green spaces and SDQ results; in public blue spaces, however, only an adverse association was found, with more conduct problems among adolescents who visited these places several times or stayed for more than 3 hours per visit. Adolescents who reported a greater quantity/quality of school green spaces had fewer conduct problems and hyperactivity/inattention, while exposure to blue spaces showed mixed associations. Spending breaks outdoors was consistently associated with fewer overall difficulties, emotional symptoms, and peer problems. Conclusions: In conclusion, exposure to green spaces, especially domestic and school green spaces, was associated with better mental health outcomes in adolescents, while blue spaces had limited or inconsistent effects.