Blatant evidence of sewage contamination, such as condoms and sanitary towels, was far more abundant. One quarter of the coastline was visibly suffering from sewage pollution, with 32 items spotted in the average mile of shore by an army of surveyors. The medical waste is also believed to enter the sea mainly through sewage outlets.
The survey was organised by Farnborough College of Technology in Hampshire, sponsored by Norwich Union and carried out in late September and October last year. About 6,000 volunteers from schools, colleges and local civic and environmental groups walked 1,145 miles of coast in Britain and Northern Ireland, noting all evidence of litter and pollution.
The survey, now in its sixth year, sampled one tenth of the United Kingdom's extensive shoreline. An average of three tyres, 27 cans, 35 plastic bottles was found per mile, while unmistakable slicks of raw sewage were smelt and seen along 50 miles.
The organisers are unable to explain why the total number of litter items fell dramatically in last year's survey, from 355,000 in 1993 to 130,000 in 1994. But they point out that even if the pollution is less dense, it is just as widespread as in 1993.
The worst sewage pollution was found on Strathclyde's beaches in Scotland, with Merseyside and Cumbria as runners up, while mid-Glamorgan in Wales had the highest number of medical waste items - six per mile.
The South-west of England had the cleanest coastline in terms of overall pollution - cans, plastic bottles, sewage and medical waste - while the North-west was dirtiest. It had at least twice as many waste items per mile.
The survey co-ordinator,Gareth Rees, of Farnborough College, concluded that only a twelfth of the coastline was in excellent condition with barely any pollution. "It's an inescapable fact that the nation's coastline remains contaminated with an unacceptable level of revolting waste,'' Dr Rees said.
Most of the waste is believed to come from British sources, but items from 27 other countries was also noticed. There was ample evidence of coastal fly-tipping of rubble and furniture as well as tyres.
The Government's National Rivers Authority surveys the sewage bacteria content of seawater at most bathing beaches throughout the spring, summer and autumn. It has found a fairly steady but gradual improvement over the past few years, which is attributedto the billions of pounds being spent on improving coastal sewage treatment.
Four out of every five beaches now pass the European Union's minimum standards for sewage pollution under the bathing waters directive.
The Government has told the European Commission that by the end of this year fewer than 10 out of a total of 400 designated beaches should fail, but this commitment seems unlikely to be met.