It's not just humans that are hit hard by second-hand smoke: it's animals too. With this in mind, leading charity PDSA is hoping to join the no-smoking crusade and encourage people to kick the habit for the benefit of their pets.

Dogs, cats and birds living in smoking households are all known to be particularly susceptible to various forms of cancer, with felines in such homes at least twice as likely to develop the disease.

"The effects of passive smoking on humans are well known," a senior PDSA vet said. "But many people don't realise their pets are also affected by breathing in second-hand smoke.

"As with people, the effects of the smoke from cigarettes will eventually take their toll on our pets. They then have to suffer the pain and distress of life-threatening cancer or chronic breathing difficulties."

National No Smoking Day will take place on Wednesday March 10.

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