ASSESSMENT OF SURFACTANTS (= LAS) IN AQUATIC ENVIRONMENTS BY QUANTITATIVE STRUCTURE-ACTIVITY-RELATIONSHIPS (QSARS)

When assessing environmental impact of organic xenobiotic water constituents, water quality management makes at present shift with summary parameters, such as COD, BOD5 or AOX. However, the assessment of single compounds or groups of compounds appears to be crucial, and with respect to many instances resolvable as well. This can be done by using simple models, which will sucessfully be demonstrated with linear alkyl benzene sulfonates = LAS. By applying linear regression equations we try to find out and quantify interrelationships between molecular structure of LAS and fate in the environment and biodegradability as well as effects of LAS. In this paper, we present Quantitative Structure-Activity-Relationships (QSARs) for LAS lipophilicity, sorption onto sediments, bioconcentration, biodegradation and toxicity. Except for biodegradation, all QSARs can be derived from the lipophilicity of the alkyl chain. By this means fate as well as effects of LAS in the aquatic environment can easily be assessed and forecasted. It appears logical, that this simple model may easily be applied to further chemicals or groups of chemical compounds.