My overall research interests center around the contamination of  drinking water by organic compounds such as chloroform, CHCl₃, when it is chlorinated with one of  the following common chlorinating agents chlorine, Cl₂, hypochlorous acid, HOCl, hypochlorite ion, OCl^-, monochloramine, NH₂Cl and dichloramine, NHCl₂.  Most of the contamination occurs when the chlorinating agent chlorinates the contaminants present in drinking water; these contaminants consist of the humic acids and various organic compounds.  The humic acids are polymeric conglomerates consisting of breakdown products from lignin (resulting from decomposition of leaves and other humic materials) and extraneous proteins and carbohyrates.  Most contaminants from the humic acids and the chlorinating agents are derived from highly reactive phenols which are primarily part of the lignin portion of the conglomerates.  Our approach to research in this area has been to select models of the phenols in the humic acids and study their reactions with the various chlorinating agents.  Examples of the phenols that we have studied are: phenol, the cresols and chlorinated cresols, resorcinol and chlorinated resorcinols,  and the pentachloride of resorcinol.

Recently an article from my research group, which involved a study of the chlorination of various phenols and the mechanisms involved, was published in the journal of Environmental Science and Technology: “Investigations of the Reactions of Monochloramine and Dichloramine with Selected Phenols: Examination of Humic Acid Models and Water Contaminants,” Heasley, V.L.; Fisher, A.M.*; Herman, E.E.*; Jacobsen, F.E.*; Ramirez, A.M.*; Royer, N.R.*; Miller, E.W.*; Whisenand, J.M.*; Zoetewey, D.L.*; Shellhamer, D.F., Environ. Sci. Technol., 2004, 38, 5022-5029.  The student authors are identified with an asterisk.  This research is of particular significance because it indicates for the first time that the chloramines appear to react with aromatic halides by an ion-radical mechanism.

The following students have recently presented aspects of their research at scientific conferences:

“Chlorination of m-Cresol, A Model of Humic Acids,” presented by Faith Jacobsen at the 37^th American Chemical Society Western Regional Meeting at Santa Barbara, CA October, 28-30, 2002.

“Reaction of the Pentachloride of Resorcinol, A model of Humic Acids,” presented by Nicole Royer at the 225^th National Meeting of the American Chemical Society, New Orleans, LA, March, 23, 2003.

“Replacement of para-Chlorine by Nitrogen in 2,4,6-Trichlorophenol: An Ion-Radical Mechanism,” presented by Evan Miller at 227^th National Meeting of the American Chemical Society, Anaheim, CA, March 28-April 1, 2004.

“Measurement of Carbon Dioxide Evolution in the Reaction of Pentachlororesorcinol with Monochloramine,” presented by Erica Herman at the 227^th National Meeting of the American Chemical Society, Anaheim, CA, March 28-April 1, 2004.

The following grants have supported the research: 
NSF: $110,000; March 2002 to March 2005.