45 household rubbish bins from three different housing type areas in Cambridge were collected separately from routine waste collection (thanks to City Council's waste collection department), and their contents (total 830kg of household waste) were hand-sorted into more than 100 categories.
The result is currently being studied in depth. Here are some figures generated from the result:
Packaging comprises 24% (in weight) or 59% (in volume) of total household waste. In terms of packaging materials, plastic has the largest share with 29%(wt) or 51%(vol) of total packaging.
Most (79%wt) of the packaging in household waste is added at the production stage, while distribution and retailing stages account for another 19%(wt).
Local differences show that in areas where milk delivery in returnable bottles is popular, the amount of discarded plastic bottles was less than half of that in other areas.
Looking at recycling performances, the City Council collected 2,043t of wastepaper last year, but the survey result implies that 4,360t of similar recyclable paper went to the waste tip in the meantime (collection rate of 32%). Glass recycling did better with 54% being collected at bottle banks.
Professor Ueta's team is carrying out identical surveys in three European cities as well as several cities in Japan, with the main focus on the possibility of packaging waste reduction. The result from Germany provides numerical evidence that they have managed to reduce packaging to some extent, although not to the degree that has been praised in some other reports.
The author believes that the outcome of this research will be useful in providing a basis for further waste management policies in Britain.