Biodegradation of surfactants

This process describes the breakdown of any organic substance by living organisms. It is a biological process and is influenced by the chemical composition, the prevailing conditions and the selection of the end point to be measured. 

The major organic components of surfactants will support biodegradation the only question is to what extent and how quickly this is achieved. In view of the large volumes of surfactants which find their way via direct or diffuse routes into the aquatic environments, it is important to understand biodegradability in the context of the potential risks to the environment. 

The use of sulphonation chemistry together with the availability of cost effective hydrocarbon feedstock led to the production and wide-scale use of synthetic surfactants in detergents during the 1950s. In particular, tetrapropylene benzene sulphonate rapidly replaced soap-based products in many applications because it does not react with calcium and magnesium in hard water to form scum . The benefits of this new surfactant together with an increasing consumer demand resulted in a substantial diffuse release of this substance into the environment. 

The result was the appearance of significant amounts of foam at water treatment plants and in rivers where there was sufficient agitation. This image of foam in rivers with some being blown in the wind has had a marked impact both on the responsibilities taken by the detergent industry as well as on subsequent legislation. 

The foam generated from the use of tetrapropylene benzene sulphonate was caused by a combination of two factors. The first of these was failure of the micro-organisms in the 

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The biodegradation of surfactants is studied by means of many different tests and sometimes under different conditions. Some factors with significant influence on the results are uncontrollable factors and in other cases are not controllable. This causes a dispersion in biodegradability data that makes comparisons difficult. For this reason only general conclusions can be obtained from the data available. Swisher carried out an exhaustive collection of available data in his complete study on surfactant biodegradation [385]. Some basic and significant features of biodegradation of alcohol and alcohol ether sulfates are discussed below. 

D R Karsa and M R Porter, Biodegradability of surfactants (Glasgow Blackie Academic and Professional, 1995). 

Scott MJ, Jones M (2000) The biodegradation of surfactants in the environment. Biochim Biophys Acta 1508 235-251... 

The second part, comprising four chapters, centers on an extensive set of data regarding the different environmental levels of all analyzed surfactants and their major degradation products in various countries. The aerobic biodegradation of surfactants is treated extensively, with emphasis on metabolic routes and novel and persistent metabolites formed. In addition, anaerobic degradation and sorption is also covered. 

In order to avoid further biodegradation of surfactants after sampling or during storage, various substances have been used for the preservation of samples. So far, mainly formaldehyde and salts of copper(II) and mercury(II) [7,14] have been applied, and formaldehyde has been found to be the most effective of these, although still not sufficient for long term storage. This topic is discussed in more detail in Chapter 4.3. 

AEROBIC BIODEGRADATION OF SURFACTANTS Thomas P. Knepper, Peter Eichhom and Lea S. Bonnington... 

Anaerobic Biodegradation of Surfactants, review of scientific information. ERASM, Brussels, 1999. 

This draft proposal for biodegradation of surfactants is a key issue for the future use of different surfactant chemical groups in detergent... 

OECD. Pollution par les Detergents, Report by Expert Group on Biodegradability of Surfactants Paris, France, 1971. 

The interest in cleavable surfactants has increased rapidly in recent years and the topic has been covered in review papers during the last decade [1-4]. This chapter begins with a relatively thorough discussion about the incentive for hydrolyzable surfactants, continues with a discussion about biodegradation of surfactants, which is important for understanding the concept of hydrolyzable surfactants, and then gives an account of the development of hydrolyzable surfactants with an emphasis on recent results. 

Painter HA (1995) BiodegradabUity testing. In Karsa DR (ed) Biodegradability of Surfactants. Blackie, Glascow... 

Cline JD, Sullivan PF, Lovejoy MA, Adams CD, Collier J, Fowler R. Ozone/ UV treatment to enhance biodegradation of surfactants in industrial waste-... 

Karsa, D.R. and Porter, M.R. (eds) (1995) Biodegradability of Surfactants. Blackie Academic Professional, Glasgow. 

Federle, T.W., and G.M.Pastwa, 1988. Biodegradation of surfactants in saturated subsurface sediments a field study. Submitted to Ground Water. 

The biodegradation of surfactants (surfactants will have to be readily biodegradable). 

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