Preliminary studies suggest that desorption-resistant napthalene may be biodegradable, and further study is continuing. In this part of the study, bioturbating worms are introduced into laboratory beds containing known quantities of contaminants and constant water flow. Researchers then measure the degree to which the worms redistribute organic carbon matter, release PAHs into the overlying water, and by aerating the sediments, assist aerobic bacteria to biodegrade the PAHs. During the feeding process, bioturbating worms also metabolize certain types of contaminants, such as pyrene. Preliminary studies showed the accumulation and degradation of readily available pyrene.
Work is ongoing to test the availability of desorption-resistant contaminants.
However, in plants there is a complex relationship among contaminant bioavailability, plant uptake, and the biodegradation process. Then they will measure contaminants in the soil, as well as in plant roots, shoots, and leaves, to measure how much of the desorption-resistant portion has been taken up and whether contaminants are available and being biodegraded in the rhizosphere.