Box 26B Experience of phosphate replacements in detergents

Germany

In West Germany in 1979, around 70 000 tonnes of phosphorus (P) were used in detergents; in 1989 the amount was a little over 5000 tonnes. The market share of phosphate-free detergents increased from 80 per cent in 1988 to more than 95 per cent in 1989­90, reducing further the amounts of phosphorus used.

In the river Rhine at Düsseldorf the annual phosphate load decreased by 64 per cent between 1979 ­ when measurements began ­ and 1989. This corresponds to a reduction of 28 400 tonnes of phosphorus per year. Phosphate concentrations were also found to have dropped by half between 1978 and 1987 in other important rivers (Ruhr, Main and Neckar).

The observed reduction in phosphate load is almost certainly due to the reduction in the use of phosphate in detergents, coupled with improved phosphorus removal during sewage treatment.

Switzerland

Phosphate content of detergents was reduced in a series of stages (1977, 1981 and 1983), until an outright ban on phosphate detergent came into force in 1987. Phosphorus concentrations declined very rapidly from 1986 onwards. In the river Rhine close to Basle, phosphorus concentrations fell from 170 µg P/l in 1979 to 130 µg P/l in 1985 and to 70 µg P/l in 1989. Similar reductions were found in lakes. The reductions are attributable to sewage treatment plants, as well as to the ban on phosphate in detergents.

Source: UNECE, 1992