Origin of p-cresol in the anaerobic degradation of trinitrotoluene

p-Cresol was repeatedly detected as a trace metabolite in anaerobic slurry reactors treating 2,4,6-trinitrotoluene (TNT)-contaminated soils. This stud y shows that p-cresol was not a metabolite of the anaerobic degradation of TNT, by using a combination of analytical techniques and C-13-labelled TNT. Instead, p-cresol, an intermediate in the degradation pathway of some amin o acids, was shown to be inhibited by TNT and its metabolites. The range an d persistence of inhibition to p-cresol microbial degradation decreased wit h the level of amino-substitution of the derivatives. This explains why p-c resol accumulated within the TNT-treating anaerobic bioslurry, as it could not be further biodegraded in the presence of TNT.