Nonylphenol ethoxylates soils

Although the occurrence of the non-ionic surfactant nonylphenol ethoxylate (NPEO Fig. 6.7.1) and its biodegradation intermediates in the aquatic environment has attracted large interest [18] because of the potential of some biotransformation products to mimic estrogenic effects, their fate and distribution in soil environments has been only investigated in a few cases. 

Nonylphenol ethoxylates (NPEOs) are extensively used as surfactants in industrial products (see Chap. 1). NPEOs are a mixture of polyethoxylated mono-alkylphenols, predominantly para-substituted, and are used in the manufacturing of paints, detergents, inks, and pesticides [435, 446]. Surfactants are common water pollutants because of their use in aqueous solutions, which are discharged into the environment in the form of wastewater from treatment plants or sludge stored in landfills. Degradation products of alkylphenol polyethoxylates, i. e., nonylphenol (NP), have the potential to be bioaccumulated, thereby becoming toxic to aquatic [447] and soil microorganisms [435,448]. 

APE use is limited to commercial and industrial applications which are not considered likely to make a large contribution to municipal sewage treatment plants, such as in textile chemicals. The alkyl chain is usually (diisobutylene), C9 (propylene trimer), or C12 (propylene tetramer). The nonylphenol ethoxylates (NPE) are used in much greater volume than the others, perhaps 80% of the market. Octylphenol ethoxylates (OPE) have about 15% of the market and dinonylphenol- and dodecylphenolethoxylates are at about 1% each. All are excellent for the removal of oily soils and can be produced at lower cost than the more abundant alcohol ethoxylates. 

Andreu V, Ferrer E, Rubio JL, Font G, Pico Y (2007) Quantitative determination of octylphenol, nonylphenol, alkylphenol ethoxylates and alcohol ethoxylates by pressurized liquid extraction and liquid chromatography-mass spectrometry in soils treated with sewage sludges. Sci Total Environ 378 124—129... 

Derivatives of nonylphenol up to about the 12-mol ethoxylate are liquid at ambient temperature and do not require heated storage. They are used for reducing oil-water interfacial tension and are excellent for removing oily soils. The major drawback is the biodegradation resistance of the benzene ring, which limits the use to industrial applications in which waste can be treated before any discharge to waterways. However, their relative cheapness has maintained their use in some formulations destined for the household market in certain parts of the world. 

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