He said second-hand smoke contained more than 4, 000 chemicals, including benzene, formaldehyde, arsenic, ammonia and hydrogen cyanide.

BBC: NEWS | UK | Northern Ireland | Legal threat over passive smoking

The Mugrabi family owns some 110 Hirsts, including an installation that features 30 sheep, two doves, a shark and a splayed cow in formaldehyde.

ECONOMIST: The art market