As I write, a posse is advancing along the beach outside, long sticks in hand.

They look like extras in a scene in Rebus, combing the sand for clues. What they are doing is less dramatic, but it's almost as important. This is Fisherrow's clean-up brigade, the human equivalent of a tide of detergent, sanitising every metre they patrol as they collect and bag a heap of detritus dropped or washed onto the shore. They could be some time. Recent figures from the Marine Conservation Society indicate that every kilometre of Scotland's coastline contains 1700 pieces of rubbish, most of them plastic.

The in-house eco-warrior has joined them, wielding the litter stick I bought him - ironically I thought - as a present some years ago. Since then it has been put to constant use, in the park and along our streets. He is one of a handful of neighbours who you'd think, at first glance, are forever dropping loose change, so often do they bend to pick something up. No journey is too short to find cans, crisp packets and bottles in need of a bin. There is one particular bench that rivals Tracey Emin's bed for mess. The Tate Modern might applaud the portrait of modern life this daily tableau of beer cans and takeaway cartons depicts, but for me it's just depressing.

It may be a sign of advancing age that litter begins to become an obsession, but once noticed, it is impossible to ignore. From trees waving polythene flags to verges so clogged with bottles you cannot see the grass, the problem seems to be getting worse. Since cleaning up costs around £75m a year, Holyrood is keen to tackle the issue. Last year it increased fines for littering and flytipping to £80 and £200, and introduced a plastic bag charge. Following the cheering success of this far-sighted measure, Richard Lochhead, Minister for the Rural Affairs, Food and Environment, now wants to ban polystyrene containers - the sort one finds in the hedge outside some mornings, with a plastic fork stuck in the ketchupped lid.

The danger of railing against other people's mess is that, because the problem never ends, you risk become a bore. Well, so be it. Not only is it unsightly but there is a direct correlation between what is called "environmental incivility" and people's fear of crime. As Clean Up Scotland, the campaigning wing of Keep Scotland Beautiful puts it, "people feel safer in cleaner communities". Added to which, wildlife is under less threat too.

Given the public funds tidying-up consumes, it remains a mystery why you hardly ever hear of someone being fined. I do, though, recall the indignation of a well-to-do Edinburgh acquaintance who had to cough up £50 for dropping her fag butt in George Street. Her response was typical: catch the real litterers - ie the less educated - not people like her. And there was a man in Hertfordshire recently who accidentally let fall a piece of tangerine peel, and went to court to protest against the fine imposed by an over-zealous council worker. In this instance, the local authority's commonsense was lost in a fog of righteousness. It would be comic, if the underlying problem were not so serious.

Clearly, official patience is wearing thin, with plans announced at Westminster to impose fines on drivers of cars from which refuse is thrown. But if it's hard to police litterers moving snail-like on foot, how much trickier at the speed of a souped-up Fiesta or 4x4?

Bit by bit, legislation will no doubt eventually catch up with culprits. Yet while law-breakers can be coaxed and fined into amending their ways, it will take a profound shift in attitudes to bring about a lasting and meaningful change of heart and habits. Litter is an existential matter, an expression of the way we think about our environment, and those we live alongside. It is a symptom of unthinking - sometimes wilful - amorality and contempt. A discarded bottle or abandoned fridge is the visible face of callous disregard for the planet - a planet that cannot sustain us if we continue to pollute it at this level. The plastic water bottle we toss away today will take 450 years to decay - hence Selfridge's enlightened decision last week to stop selling them. As for glass, it can last millennia.

We seem awfully keen to provide jobs for archaeologists of the future. Not satisfied with ruining our landscapes, countryside and seas to a point beyond repair, the human race appears to have an unstoppable urge to stamp its footprint indelibly on the face of the earth. Unlike most offenders, however, litterers make no attempt to remove the evidence of their crimes. They are clueless only in the wider sense.