Polycyclic aromatic hydrocarbons (PAHs) are an important
class of environmental contaminants because some of them are
toxic, mutagenic and resist biodegradation [1]. Possible fates of
PAHs released into the environment include volatilization, photooxidation,
chemical oxidation, bioaccumulation, and adsorption on
soil particles [2]. Soil clean-up may be accomplished using different
remediation technologies. Among these, bioremediation is an
effective and low-cost alternative that has garnered widespread use
[3].
Two processes have been found to increase the activity
of microorganisms during bioremediation: biostimulation and
bioaugmentation. Biostimulation involves the addition of nutrients
and/or a terminal electron acceptor to increase the scant activity
of indigenous microbial populations. Bioaugmentation involves
the addition of external microbial strains (indigenous or exoge-