The rising air pollution in India is pumping up the business of air purifiers, which until three years ago were mainly bought by those with respiratory problems, reported Times of India.

"The level of pollution has risen dramatically over the last few years, and it is worrisome. We are currently witnessing heavy demand as consumer concern goes up around this time of the year," Ahraaz Khan, marketing head of Honeywell Building Technologies, told the paper.

The biggest market for air purifiers is north India, which has many of the worst air-polluted cities in the world.

New Delhi, Noida, Ghaziabad, Faridabad, Jaipur, Kanpur, Varanasi, Lucknow and Ludhiana, are among the top demanders of the air purifiers. The cities have already reached "severe" air quality index (AQI) in excess of 400.

"In Bengaluru, there are instances of allergy due to pollen, while in Mumbai, the Metro construction and general vehicular pollution is adding to dust," Honeywell's Khan told the paper.

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