Synthetic Detergents: Their Influence upon Iron-Binding Complexes of Natural Waters

Organic compounds extracted from Michigan lakes and streams and added to algal cultures increase the growth rate of the green alga (Chlamydomonas reinhardi) when iron is present. Two-dimensional paper chromatography has shown that the iron is complexed by organic fractions containing an amine group. When isolated from natural waters containing a concentration of over 0.3 part per million alkyl benzene sulfonate, these compounds do not show an iron-binding capacity. Separation of this sulfonate from the amine complexes restores the iron-binding capability. These findings suggest that detergents may influence the mobility of iron by reducing the number of binding sites, and in this way may have an important secondary effect upon the primary production of lakes and streams.