Supplementary Materials: Environmental Characterization of the Wood Smoke-Derived PM$_{2.5}$ Exposure Model

These supplementary documents provide environmental and methodological context for the experimental exposure model used to evaluate the effects of maternal wood smoke-derived PM₂.₅ exposure on fetal neurocranial intramembranous ossification in Sprague–Dawley rats. Supplementary Document 1 describes the location of the exposure chambers in Temuco, Chile, near the official environmental monitoring station. Supplementary Document 2 presents daily PM₂.₅ concentrations recorded at the Las Encinas Monitoring Station during the study period. Supplementary Document 3 summarizes PM₂.₅, PM₁₀, and CO concentrations during the experimental exposure period and annually. Together, these files support the environmental characterization of the biomass-derived air pollution exposure scenario used in the study. Supplementary Document 1. Exposure chamber location and environmental context This document shows the location of the atmospheric exposure chambers used in the experimental study. The chambers were installed in the courtyard of the Faculty of Medicine at the University of La Frontera, in downtown Temuco, Chile, approximately 500 m from the official environmental air monitoring station. The document includes geographic contextualization and images of the exposure site, supporting the environmental relevance of the chamber-based PM₂.₅ exposure model. Supplementary Document 2. Daily PM₂.₅ concentrations during the study period This document presents daily PM₂.₅ concentrations recorded at the Las Encinas Monitoring Station in Temuco, Chile, from January 1 to September 30, 2021. PM₂.₅ levels were measured using a beta attenuation monitor BAM 1020, and the dataset distinguishes validated, preliminary, and unvalidated records. This file provides temporal environmental context for the PM₂.₅ exposure conditions during the study period. Supplementary Document 3. Summary of particulate matter and carbon monoxide concentrations This document summarizes average concentrations of PM₂.₅, PM₁₀, and carbon monoxide during the experimental exposure period, from June 15 to September 30, 2021, and compares them with annual values. During the study period, mean PM₂.₅ concentration was 48.8 ± 36.1 µg/m³, PM₁₀ was 56.9 ± 38.3 µg/m³, and CO was 0.78 ± 0.49 ppm, supporting the characterization of the austral winter pollution scenario in Temuco.