Domestic waste water is a complex and delicate subject, particularly the various items which find their way into sewers and are technically known as "gross sanitary solids".

These include sanitary towels, panty-liners, tampons, condoms, incontinence pads, cotton wool buds and disposable nappies, all of which can block sewers and water treatment plants, as well as leaving an unsightly mess in rivers and on beaches.

Even when they degrade, they provide the main organic component of sewer sediments, a breeding ground for bacteria. Many of them also contain non-biodegradable plastic, which makes sewage sludge awkward to handle and dispose of later.

"Scant attention has been paid to the broad issues associated with the suitability of sewers as a means of disposing of large solids," says Richard Ashley, director of the waste water technology centre at the University of Abertay Dundee.

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He is heading a research consortium which includes Imperial College, Westminster University, Dundee District Council, Tayside Regional Council and Tayside Health Board, which could lead to fundamental changes in the way people deal with domestic waste.

Several national and local campaigns are trying to persuade the public not to put gross solids into the waste water system, but to use their dustbins instead. They see potential cost savings both in treatment plants and in avoiding pollution caused by overflows.

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But little research has been done on the cost-effectiveness of such publicity, or on the implications for the design and management of sewers and water treatment systems as a result of changes in public habits.

"The means of achieving any improvements to current systems will be partly social and partly technical, and must take account of the economic and health aspects of any culture change," Mr Ashley said.

The multidisciplinary research team includes engineers, economists, lawyers, planners, solid waste and wastewater system managers, public health experts, and environmental assessment and energy specialists.

The team will study current practice and alternative methods through a pilot scheme in Dundee, including ways in which people could be persuaded to change their habits. "Dundee is particularly suitable for this research, since it already has a high reputation for its radical approach to waste management, such as extensive composting systems for household waste," Mr Ashley said.

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The project has attracted almost Pounds 100,000, with the bulk coming from the Clean Technologies/Engineering and Physical Sciences Research Council initiative, "Towards the Sustainable City".