This supplementary material provides additional details and data for the study on early-life exposure to tobacco, genetic susceptibility, and accelerated biological aging in adulthood. It includes: 1. **Air Pollution Measurement**: - The annual average concentrations of air pollutants (NO₂, NOₓ, PM₂.₅, PM₁₀) were assessed using the Land Use Regression (LUR) model, developed by the ESCAPE project. The model evaluates individual exposure levels based on GIS data, traffic intensity, land use, topography, and population density. Cross-validation R² for the pollutants ranged from 77% to 88%. 2. **Code for Accelerated Biological Aging Estimation**: - The code for estimating accelerated biological aging using the KDM and PhenoAge methods is provided. The code reads data from the UK Biobank, processes biomarkers, and calculates biological ages. The results are saved for further analysis. 3. **Tables and Figures**: - **Table S1**: Comparisons of characteristics between the total population and included participants. - **Table S2**: Associations of in-utero exposure to tobacco smoke and age of smoking initiation with standardized accelerated biological aging. - **Table S3**: Associations of in-utero exposure to tobacco smoke and age of smoking initiation with biological aging in participants with complete covariates. - **Table S4**: Associations of in-utero exposure to tobacco smoke and age of smoking initiation with accelerated biological aging in model 3. - **Table S7**: Associations of polygenic risk scores with accelerated biological aging among participants of European descent. - **Table S8**: Associations of in-utero exposure to tobacco smoke with accelerated biological aging according to characteristics of study participants. - **Table S9**: Associations of age of smoking initiation with accelerated biological aging according to characteristics of study participants. - **Table S10**: Data field IDs of biomarkers for the construction of biological age in the UK Biobank study. - **Table S11**: Summary results of the SNPs used for PRS of PhenoAge, KDM-BA, and telomere length. - **Fig. S1**: Correlation matrix of chronological age, biological ages, and age accelerations. - **Fig. S2**: Flowchart for the selection of study participants for analysis. - **Fig. S3**: Directed acyclic graphs illustrating the effects of early-life tobacco exposures on accelerated biological aging, including potential confounders for in-utero exposure to tobacco smoke and age of smoking initiation. This supplementary material supports the main findings and provides detailed methods and data for the study.This supplementary material provides additional details and data for the study on early-life exposure to tobacco, genetic susceptibility, and accelerated biological aging in adulthood. It includes: 1. **Air Pollution Measurement**: - The annual average concentrations of air pollutants (NO₂, NOₓ, PM₂.₅, PM₁₀) were assessed using the Land Use Regression (LUR) model, developed by the ESCAPE project. The model evaluates individual exposure levels based on GIS data, traffic intensity, land use, topography, and population density. Cross-validation R² for the pollutants ranged from 77% to 88%. 2. **Code for Accelerated Biological Aging Estimation**: - The code for estimating accelerated biological aging using the KDM and PhenoAge methods is provided. The code reads data from the UK Biobank, processes biomarkers, and calculates biological ages. The results are saved for further analysis. 3. **Tables and Figures**: - **Table S1**: Comparisons of characteristics between the total population and included participants. - **Table S2**: Associations of in-utero exposure to tobacco smoke and age of smoking initiation with standardized accelerated biological aging. - **Table S3**: Associations of in-utero exposure to tobacco smoke and age of smoking initiation with biological aging in participants with complete covariates. - **Table S4**: Associations of in-utero exposure to tobacco smoke and age of smoking initiation with accelerated biological aging in model 3. - **Table S7**: Associations of polygenic risk scores with accelerated biological aging among participants of European descent. - **Table S8**: Associations of in-utero exposure to tobacco smoke with accelerated biological aging according to characteristics of study participants. - **Table S9**: Associations of age of smoking initiation with accelerated biological aging according to characteristics of study participants. - **Table S10**: Data field IDs of biomarkers for the construction of biological age in the UK Biobank study. - **Table S11**: Summary results of the SNPs used for PRS of PhenoAge, KDM-BA, and telomere length. - **Fig. S1**: Correlation matrix of chronological age, biological ages, and age accelerations. - **Fig. S2**: Flowchart for the selection of study participants for analysis. - **Fig. S3**: Directed acyclic graphs illustrating the effects of early-life tobacco exposures on accelerated biological aging, including potential confounders for in-utero exposure to tobacco smoke and age of smoking initiation. This supplementary material supports the main findings and provides detailed methods and data for the study.