EFFECT OF MICROBIAL POLYMERS ON THE SORPTION AND TRANSPORT OF PHENANTHRENE IN A LOW-CARBON SAND

Extracellular polymers of bacterial origin were analyzed for their eff ect on the sorption behavior of phenanthrene on a low-carbon aquifer s and. Batch experiments indicated that 85% of the polymers tested acted to decrease the distribution coefficient. Column experiments revealed a decrease in the retardation factor of phenanthrene by approximately 40% in the presence of an extracellular polymer produced by a Gram-ne gative motile rod isolated from a coal tar waste site. This polymer di d not, however, influence the mineralization of phenanthrene and was n ot rapidly degraded by a mixed culture. The combination of the ability of the polymer to influence phenanthrene transport as well as its app arent persistence and lack of a negative effect on phenanthrene degrad ation suggest that extracellular polymers can act as agents that enhan ce PAH transport in natural systems.