Air Pollution May Play a Role in Alzheimer’s Disease
The nasal cavity is a common route of entry for inhaled air pollutants.
A study has shown that the nasal mucus membrane defenses are severely compromised in children in Mexico City, diminishing protection from inhaled pollutants. Researchers hypothesized that inflammatory processes in the respiratory tract could trigger a chain of events involving the brain.
This study found that Mexico City dogs chronically exposed to high concentrations of ozone, PM, and other air pollutants had extensive brain damage compared to dogs from a less polluted city. Researchers observed alterations of the blood-brain barrier, degenerating, shrunken nerve cells surrounded by dying white matter cells, plaques, and neurofibrillary tangles.
Researchers concluded that “the histopathology we observed in these urban dogs is of sufficient magnitude to warrant concern that similar histopathology may be occurring in humans residing in large polluted metropolitan areas,” and that “persistent pulmonary inflammation and deteriorating olfactory and respiratory barriers may play a role in the neuropathology observed in the brains of these highly exposed canines. Neurodegeneratiave disorders such as Alzheimer’s may begin early in life with air pollutants playing a crucial role.”
Calderon-Garciduenas, L., Valencia-Salazar, G., RodrÍguez-Alcaraz, A., Gambling, T.M., GarcÍa, R., Osnaya, N., Villarreal-Calderon, A., Devlin, R.B., and Carson, J.L. Ultrastructural Nasal Pathology in Children Chronically and Sequentially Exposed to Air Pollutants. Am. J. Respir. Cell Mol. Biol. Vol. 24, pp. 132-138, 2001. The American Thoracic Society [ajrcmb.atsjournals.org] offers the full article online.
Calderon-Garciduenas, L., Azzarelli, B., Acuna, H., Garcia, R., Gambling, T.M., Oznaya, N., Monroy, S., Del Rosario Tizapantzi, M., Carson, J.L., Villarreal-Calderon, A., and Rewcastle, B. Air Pollution and Brain Damage. Toxicologic Pathology, Vol. 30, No. 3, pp. 373-389, 2002. Toxicologic Pathology offers the abstract online.
