A QSBR DEVELOPMENT PROCEDURE FOR AROMATIC XENOBIOTIC DEGRADATION BY UNACCLIMATED BACTERIA

The relationship between chemical structure and the comparative rate o f biodegradation (defined here as the biodegradation index) by unaccli mated activated sludge has been studied. The findings of one model ill ustrate that the relationship between structure and biodegradability f or a homologous series of aromatic compounds may be easily developed u sing techniques drawn from medical and pharmacological sciences, in th is case, Hammett's constants. This is true when the biodegradation pat hway is known. However, such a model is not broadly applicable to a di verse group of substances where such pathway information is not availa ble. A second model was developed using a newer technique-molecular co nnectivity indices-which does not require pathway information. The sec ond model was calibrated with the data employed in the first model. Th is model did not contain specific pathway of directional information, but successfully predicted the rates at about the same confidence leve l as the first.