Background and Objective:
Eco-anxiety describes the mental distress resulting from extreme concern about environmental circumstances as well as the effects of climate change. The study aims to measure eco-anxiety, identify its determinants, and assess the associations between eco-anxiety and health, as well as pro-environmental behaviors in participants of Generation XXI birth cohort at the ages of 16/17 years.

Methods:
A cross-sectional evaluation based on a web-based questionnaire is currently on-going in the entire cohort (N= 8647). Eco-anxiety was assessed using Hogg et al. scale (2021), which was translated and culturally adapted to Portugal. The Beck Anxiety Inventory was used to assess generalized anxiety. The adoption of pro-environmental behaviors was evaluated using an adapted version of the Kaiser et al. (2007) instrument. Eco-anxiety scale was categorized in quintiles. Linear and logistic regression were used to estimate associations.

Results:
We found that 18.5% of the participants have some degree of eco-anxiety, scoring higher than 9 (scale from 39). Individuals in the top quintile (quintile 5) of eco-anxiety were more likely to be females [OR=3.9, 95%CI 1.9-8.1] and have poor self-rated health [OR=2.4 1.0-5.6] when compared to those with lower scores (quintiles 2-4). Higher levels of generalized anxiety were associated with higher eco-anxiety scores [β=0.16, 0.12-0.21]. Participants scoring higher in the eco-anxiety scale engaged more often in collective (e.g., activism [β=0.03, 0.01-0.04], nature conservation initiatives [β=0.06, 0.04-0.08]) and some individual pro-environmental behaviors (e.g., reduced meat consumption [β=0.06, 0.04-0.09], recycling [β=0.04, 0.01-0.07]). They also more frequently read/look for information about environmental problems [β=0.08, 0.05-0.10].

Conclusions:
These preliminary results showed that eco-anxiety is more common in females and seems to be associated with generalized anxiety and poorer self-rated health. Eco-anxiety appears to prompt adolescents to adopt some proactive behaviors. Because the data collection is still ongoing these results should be interpreted with caution.