The talk by 2023-24 AEESP DISTINGUISHED LECTURER, Elizabeth A. Edwards, Ph.D., P.Eng. will be followed by a poster session and reception. 

Groundwater contamination is a serious threat to global health and prosperity.  Petroleum hydrocarbons, industrial solvents, pesticides, herbicides, and metals are some of the most frequent culprits.  Some microbes have evolved and adapted to transform or detoxify contaminants.  Certain species, such as Dehalococcoides, can dechlorinate the major dry-cleaning solvent tetrachloroethene and the common industrial solvent trichloroethene to the benign product ethene.  Remarkably, these organisms obtain energy for growth from dechlorination, and several successful demonstrations of bioaugmentation, where an aquifer is inoculated with a mixed microbial culture, have led to the development of a viable commercial market for such dechlorinating cultures.  By studying enrichment cultures and their megagenomes, we are learning more about novel interspecies interactions in these remarkable, ubiquitous, anaerobic microbial communities, and their specialized enzymes that catalyze reductive dehalogenation reactions.  Benzene is another problematic contaminant, readily degraded under oxic conditions, but highly persistent in anaerobic environments.  The anaerobic metabolism of benzene is complex and still largely unknown, yet clues are emerging that reveal novel microbes, pathways and enzymes that could be harnessed for cleanup.  Prospects for biodegradation of other contaminants, including the pesticide chlordecone and perfluorinated substances will be discussed.

Guests arriving before 3:30pm must pay for parking.