Belgians rubbish the idea of revealing their dirty secrets: While many Community countries grapple with the continuing problem of waste disposal, recycling has become a political hot potato

BELGIUM is suffocating under the weight of 3.5 million tons of rubbish a year, safe disposal of which is taxing the imagination of political leaders as they search for solution that is cheap and ecologically sound.

The latest dispute has been sparked by a plan to introduce a new system of rubbish collection in Brussels, which must be one of Europe's filthiest capitals. Householders are to be issued with coloured sacks enabling them to separate household waste: paper in the yellow bag, metal, glass, cardboard in the blue one, and anything else in the black.

But vociferous representatives of the government's liberal wing have objected that the scheme constitutes an invasion of personal privacy. To ensure that household waste is properly sifted, the bags must be transparent: alcoholics and readers of pornographic literature would be unmasked for all to see.

This is a peculiarly Belgian problem. Here, the dustbin is not favoured. Rubbish tied in plastic sacks is deposited on the pavement outside the front door no earlier than 8pm on the eve of collection day.

It is one of the eccentricities of Belgian life that no one explains and so it was that a recent arrival, my neighbour Paola, blissful in her ignorance, dared to dump her rubbish outside two days early. Evening brought a visit by two policeman: they had gone through the the rubbish, had seized upon two addressed envelopes and a can of tomato paste as proof of ownership and demanded an on-the-spot fine. It is apparently socially acceptable here to rootle through someone's rubbish if you are a policeman.

Paola was unlucky: most first- time rubbish offenders get off with a written warning from the town hall, an acknowledgement that the practice of dumping rubbish outside an unknown door outside collections days is widespread.

Under Belgium's federal system, responsibility for waste diposal rests with regional authorities and there are numerous complaints of cross- border dumping and pollution. The river Senne, for example, has its source in Wallonia, but flows into the Schelde in Flanders - through three different regions, each of which has its own independent environment policy - by which time it is heavily polluted. Flanders complains it has to foot the cleaning bill. 'The problem is that it is only the green parties (one Flemish, one Francophone) which talk to each other about the environment,' complained Luc Barbe, an MP for Agalev, the Flanders green party.

Central government has tried to limit pollution and waste at source. From next year, Belgians will be forced to pay 'eco-taxes' of up to 50p on glass bottles, tin cans, plastic bottles, disposable razors and cameras, batteries, industrial products, non-agricultural pesticides and some newspapers.

But lobbying by industry means there are now so many exceptions to the rules and such long transition periods that many complain the effect of the taxes will be negligible in terms of the environment, do little to change public behaviour, but risk stoking inflation.

The proceeds of the tax are to be reinvested in environmental protection by the regions. Antwerp has led the way with a pounds 2.5m investment in a paper-pulping monster called Dranco, a system that is successfully used in Salzburg. Dranco can chew through 40 to 50 tons of carton a day mixed with ordinary organic rubbish, converting it to a harmless biogas.

But Belgium fears the example of Germany, where recycling has been so effective that it cannot process the recycled matter fast enough and is reduced to dumping it on neighbours.