Association between ambient air pollution exposure and pubertal development: An ecological study

The incidence rate of precocious puberty (PP) is rising, and ambient air pollutants may influence pubertal timing. This study explores the association between air pollution and PP and normal variants of puberty (NVP) in a Spanish pediatric population.

We conducted a retrospective ecological study in Asturias, Spain. Children ≤9 years diagnosed with PP or NVP between 2021 and 2024 were included. Data on pollutants (PM₁₀, PM_2.5, SO₂, NO₂, CO, O₃, NO, NO_x) from the 2 years prior to diagnosis were obtained from the nearest monitoring stations. The region was divided into 12 zones, yielding 48 zone-years across the 4-year study period. Incidence rates and mean pollutant levels were calculated for each zone. Each zone-year was classified as having high or low exposure according to the median pollutant concentration.

A total of 96 children were diagnosed with central PP (n=53), peripheral PP (n=3) or NVP (n=40). Overall PP incidence (either central or peripheral PP) was positively correlated with CO (rho=0.479, p=0.024) and NO_x (rho=0.391, p=0.033) concentrations. We found no statistically significant associations between the incidence of central PP and any air pollutant. However, there was a trend toward a positive correlation between central PP incidence and CO exposure (rho=0.389; p=0.074). In addition, central PP incidence was higher in high-exposure areas for all pollutants, although these differences were not statistically significant (p>0.05).

The findings of our study suggest a possible environmental influence on PP that needs to be explored in larger, longitudinal studies.