Your laundry and the environment Each time a washing machine empties, water loaded with soil removed from the fabrics, and with the chemicals used in the detergent, is discharged into the sewer. Various measures are routinely used to assess the possible impact on the environment of a detergent formulation and its ingredients. In addition, phosphate, alone amongst detergent ingredients, has the potential to be recovered and recycled from sewage treatment works - either as sludge for application as fertiliser for agricultural land or, using emerging techniques, as high grade products for industrial, detergent or even food and pharmaceutical use.
Nutrient enrichment is a natural process.
It is not unusual to find lakes and rivers which have become rich in the main nutrients including carbon, silicon, nitrogen and phosphorus by erosion or runoff from adjacent soils. In surface waters and, in particular oceans, this primary production speeds the diffusion of carbon dioxide from the atmosphere to the oceans, the largest sink for carbon dioxide. These planktivorous fish are consumed by larger predatory fish which, together with their prey, are the food for birds and mammals and, indeed, man. A healthy food chain can often show remarkable resilience to large changes in nutrient load or climatic conditions without showing any long term changes in water quality or species diversity. However, the pressures of an expanding population, urbanisation, industrialisation and agricultural intensification in many regions have resulted in a massive increase in the loading of, not just nutrients into rivers, lakes and estuaries, but untreated or partially untreated sewage.