About the same size as fine particles of cigarette smoke, the grains are made of silicate minerals and carbon-based materials coated with ice - principally water ice and frozen carbon monoxide.

BBC: University of Nottingham

Toxic particles in cigarette smoke can remain on nearby surfaces, as well as the hair and clothing of the smoker, long after the cigarette has been put out, and small children are susceptible because they are likely to breathe in close proximity, or even lick and suck them.

BBC: Warning over 'third-hand smoke'

The visible particles and clouds of smoke in the scene react to other objects using fluid dynamics simulation.

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That, although it got rid of the smoke, increased the quantity of the microscopic particles Electrocat is designed to remove.

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Components of tobacco smoke such as carbon monoxide, nicotine, benzene and small particles can easily be measured in the air of a smoker's home or workplace.

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