Kendalem Asmare Atalell, Gavin Pereira, Sylvester Dodzi Nyadanu, Bereket Duko, Ivan C Hanigan, Gizachew A Tessema
Early childhood PM2.5 exposure was associated with increased developmental vulnerability at school entry in this low-exposure setting. Although prenatal and early childhood exposures were highly correlated, precluding identification of a definitive critical exposure period, the greatest associations in this study were observed during early childhood exposure period. These findings support continued efforts to reduce children's exposure to PM2.5, particularly among socially and biologically vulnerable populations.
BACKGROUND: Fine particulate matter air pollution (PM2.5) has been associated with adverse neurodevelopmental outcomes. Yet, evidence from whole-of-population studies examining developmental vulnerability at school entry remains limited, particularly in low-exposure settings. We investigated associations between prenatal and early childhood PM2.5 exposure and developmental vulnerability at school entry in Western Australia.
METHODS: We conducted a population-based cohort study using linked records from the Australian Early Development Census (AEDC), Midwives' Notifications System (MNS), Birth Registrations, and Hospital Morbidity Data Collection (HMDC). Children from the 2009, 2012, and 2015 AEDC waves were assigned daily PM2.5 exposure at the Statistical Area Level 2. Mean PM2.5 concentrations were calculated for prenatal (conception to birth), early childhood (birth to AEDC assessment), and cumulative (conception to AEDC assessment) exposure windows. Developmental vulnerability was defined as scoring below the 10th percentile cut-off established in the 2009 AEDC for each developmental domain. Associations were estimated using Bayesian multilevel logistic regression models.
RESULTS: Among 54,458 children, mean PM2.5 concentrations ranged from 7.40 to 7.54 μg/m3. Early childhood PM2.5 exposure was associated with increased odds of developmental vulnerability in one or more domains (DV1: OR 1.04, 95% CrI 1.01-1.07), two or more domains (DV2: OR 1.06, 95% CrI 1.03-1.08) per 1 μg/m3 increase. Associations were observed for physical health and well-being, social competence, and language and cognitive skills (school-based). No associations were observed for prenatal or cumulative PM2.5 exposure.
CONCLUSION: Early childhood PM2.5 exposure was associated with increased developmental vulnerability at school entry in this low-exposure setting. Although prenatal and early childhood exposures were highly correlated, precluding identification of a definitive critical exposure period, the greatest associations in this study were observed during early childhood exposure period. These findings support continued efforts to reduce children's exposure to PM2.5, particularly among socially and biologically vulnerable populations.