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/* Environmental Facts - washing, boiling / bykning */
Regarding detergents the most important thing is to receive data on their [[toxicity]], [[biodegradability]], and ability to accumulate in living organisms. The laundry chemicals always contain surfactants and complexing agents. Solvents have been used in Sweden in order to speed up the washing process. It is important to get as much information as possible by detergent manufacturers. For general information about the environmental effects of various surfactants and complexing agents please see the Tox Info-guide (Tox-handboken). Often, non-ionic surfactants are used to obtain a sufficiently rapid and efficient washout of the chemicals used in spinning. Previously, the dangerous alkylphenolethoxylates (APEO) where used but they were replaced by alcohol. The alcohol should ideally have a linear hydrocarbon chain with a maximum of 18 carbon atoms. The alcohol is the primary and the number of ethylene oxide units should be no more than 20-30 in order to be biodegradable. Previously, polyphosphates were used as complexing agent during washing, but after the requirement for lower phosphate concentrations got in effect the most used substances are EDTA, NTA and phosphonates since they are very effective even at low concentrations. It is not considered suitable for the textile industry to use zeolites and polycarboxylic acids, which are used in household detergents. The criticism of phosphate substitutes may lead to a reassessment of polyphosphates regarding the water use.
EDTA, NTA and phosphonates have been questioned primarily because of their ability to loosen [[heavy metals]]. Today,all [[blechingbleaching]] in Sweden is done with [[peroxides]]. It has increased the need for effective complexing agents that otherwise would jeopardize the bleaching of cotton grown on iron-rich soils. If he iron metals cannot be removed properly in the pretreatment, there is a limitation for potential reuse of evaporated alkaline liquors in subsequent processes. After washing there is usually a pH control (deacidification), typically in acetic acid. If the product proceeds to bleaching, the alkali residues do not need be removed.
In the event of a total ban on the use of [[phosphates]] in detergents, the need for substitutes will increase for EDTA, NTA and zeolites. This may mean that the compensation solutions may need to be revalued from an environmental and health perspective because they may not be appropriate to use in large quantities. [1]
