Sir, – While agreeing with Thomas G Cotter’s letter (May 15th) regarding dog fouling and the need for a public awareness campaign, I would like to suggest a second awareness campaign regarding the casual disposal by smokers of cigarette butts on our streets and pavements.There seems to be zero awareness among most smokers that their discarded cigarette butts do not biodegrade. Cigarette filters are made of a plastic called cellulose acetate. When tossing butts into the environment, smokers dump not only that plastic, but also the nicotine, heavy metals and many other chemicals the filters have absorbed, into the surrounding environment, degrading our soil, rivers and seas.It’s hard to ignore smokers casually flicking their butts outside of shops, restaurants and pubs every day, all of which seems to be socially acceptable. I cannot recall a government campaign to try to address this behavioural problem. Smokers make a conscious choice regarding the risks to their health by continuing to smoke. But it is high time to address their lack of awareness of the damage this disgusting habit is causing to the wider environment and our overall health. – Yours, etc,Aiden Creavin,Glasnevin,Dublin11.