Dr. C. Mary Schooling, professor at the CUNY School of Public Health, and colleagues examined the association of air pollution with pubertal development, using evidence from the “Children of 1997” Birth Cohort. The findings were published in the American Journal of Epidemiology.
Many pollutants are endocrine disruptors which impact reproduction and health in animals. Similar evidence in humans, of which sex-specific effects on pubertal development may be an indicator, is less clear. The research team examined the association of air pollution in utero and during early life with pubertal development in Hong Kong, China, an area with a high level of air pollution compared with other similarly developed cities.
The team assessed sex-specific associations of particulate matter less than or equal to 10 μm in diameter (PM10), nitric oxide, sulfur dioxide, and nitrogen dioxide in different growth phases with clinically assessed pubertal stage at approximately age 11 years (as indicated by Tanner stage) in a large population-representative birth cohort, the “Children of 1997.”
Among 1,938 girls, exposure in utero and during infancy to particulate matter less than or equal to 10 μm in diameter was negatively associated with pubertal stage and breast development, whereas among 2,136 boys, sulfur dioxide and nitrogen dioxide exposure in utero, during infancy, and in childhood were negatively associated with pubertal stage.
The authors concluded that these sex-specific associations with pubertal development are consistent with endocrine-disrupting effects. Given the health impact of altered pubertal timing, further investigation across the life course may help quantify the full effects and the corresponding need for preventive measures.