CHEMICAL SIGNATURES AS CRITERIA FOR DETERMINATION OF MICROBIALLY COLONIZED AQUATIC PARTICLES.

The paper discusses studies utilizing scanning electron microscopy with Automated image analysis and X-ray energy spectrometry (SAX) to determine individual particle chemical signatures. By examination of secondary effluent which contained many colonized particles, the SAX technique was shown to be useful. Further examination of Los Angeles Aqueduct Water, containing both colonized and non-colonized particles, resulted in the establishment of a discrimination based on particle chemistry. Results indicate that colonized particles contain at least two of the following elements: Cl, P, and S, as well as an organic (biofilm) coating. Non-colonized particles do not show these features, and therefore individual particle analysis can be used to discriminate between colonized and non-colonized particles.