Thailand Warns Prolonged PM2.5 Exposure Increases Stroke, Dementia Risk by 24% per 5 µg/m³ Rise

Prolonged exposure to PM2.5 air pollution is linked to an increased risk of stroke and dementia, with every 5 microgram per cubic metre increase raising the risk of paralysis and recurrent stroke by 24%, according to health officials in Thailand.

The warning comes as Thailand faces its annual air pollution crisis, particularly during the winter and summer months when dry weather and still air allow fine particulate matter to accumulate. Doctors warn that PM2.5 enters the body and brain, triggering oxidative stress, inflammation, and hardening of blood vessels, which can damage brain blood vessels across all age groups.

Prolonged exposure to PM2.5 can increase the accumulation of amyloid protein in the brain, a primary cause of Alzheimer’s disease and dementia. The negative effects on the brain can begin in childhood, potentially contributing to delayed development, lower IQ, and mood disorders.

In 2024 alone, around 3 million Thais suffered from illnesses linked to PM2.5, including chronic obstructive pulmonary disease, acute asthma, conjunctivitis, allergic dermatitis, and urticaria, according to data from Thailand’s Public Health Ministry.