Timing of manganese exposure impacts adolescent cognition, study reveals

Prenatal manganese exposure is linked to lower odds of intrusion errors in adolescent cognition, while childhood manganese exposure is associated with improved short-delay free recall, particularly in males, according to a recent study.

Manganese (Mn), a metal that is both essential and potentially toxic, has long intrigued researchers due to its intricate relationship with neurodevelopment. However, the timing of exposure to manganese and its specific impact on cognitive function in adolescents has remained relatively unexplored until now.

The study enrolled 140 Italian adolescents, aged between 10 and 14 years, in the Public Health Impact of Metals Exposure study. Researchers assessed manganese levels in deciduous teeth, providing insights into prenatal, postnatal, and early childhood exposure to the metal.

A doubling in prenatal manganese levels was associated with lower odds of making an intrusion error, indicating a protective effect of early exposure on cognitive function. However, this beneficial association was not observed for other exposure periods.

In contrast, childhood manganese exposure exhibited a different influence. A doubling in childhood manganese levels was beneficially associated with short-delay free recall. This cognitive benefit was particularly pronounced in males. Once again, these associations were not observed for manganese exposure during the postnatal period.

Reference: Alexa Friedman, Samantha Schildroth, Julia A. Bauer, Brent A. Coull, Donald R. Smith, Donatella Placidi,et al,Early-life manganese exposure during multiple developmental periods and adolescent verbal learning and memory, Neurotoxicology and Teratology, Volume 100, 2023, 107307, ISSN 0892-0362, https://doi.org/10.1016/j.ntt.2023.107307.(https://www.sciencedirect.com/science/article/pii/S0892036223001575)