A recent survey conducted by an environmental organisation, Coastal Resource Centre at Ennore creek, has produced alarming results: PM 2.5 levels record 2.3 times higher than the prescribed limits and could increase the risk of Alzheimer’s disease among Chennaiites as mentioned in a study.

Increased indoor and outdoor air pollution, which causes cardiovascular and lung diseases, has been reported to have serious impacts on mental health, and studies have found a possible link between dirty air and Alzheimer’s disease.

Researchers from Lancaster University in the United Kingdom have found millions of magnetite particles in 37 human brain tissue samples collected from pollution hot spots around the world. The researchers said that after the magnetite particles were examined, it was found that it had the same appearance as that in the atmosphere, indicating that they had not been dissolved or broken down in anyway.

The WHO report stated that 92 per cent of the world’s population lives in places where air pollution levels exceed acceptable limits. It also said that in 2012, approximately 6,00,000 Indians died from effects of air pollution.

In Tamil Nadu, the industrial belt of Manali-Ennore region has become a hub for harmful pollutants, as the air monitoring by the Tamil Nadu Pollution Control Board shows the exceeding of the PM 2.5 levels in Manali, Tiruvottiyur, T Nagar and Ennore regions.

“Compared to other metropolitan cities, Chennai is slightly better. However, on certain days, in certain areas, the pollution levels exceed the recommended WHO level,” said pulmonologist Dr MuruganNatarjan.

The study, released in September, however, does not claim a definite link between air pollution and Alzheimer’s but offered evidence that magnetite from air pollution, particularly traffic pollution, can get into the brain.