• Environmental Quality


    Watershed Level Examination of Urea Use as Fertilizer and the Production of the Biotoxin Domoic Acid


    NON-TECHNICAL SUMMARY: Worldwide production of ammonium nitrate and anhydrous ammonia has decreased significantly in the years following the bombing of the Oklahoma Federal Building. To ensure continued availability of nitrogen as fertilizer, a subsequent rise in the use of urea as an alternative has occurred. Recent reports in the United States from Monterey, Calif., and from other parts of the world have shown that the diatom Pseudo-nitzschia has been on the increase, and suggestions have been made that this could be in response to the increased use of urea, which has been found in many of the world's riverine systems. Pseudo-nitzschia is the algae responsible for the production of domoic acid, which is a potent neuro-toxin affecting memory and movement in humans and disorientation and behavior in mammals. This project is designed to link the application of urea fertilizer or chicken litter containing urea to the surface and subsurface movement of urea into rivers and streams; to determine the instream movement and fate of urea; to determine the distribution of Pseudo-nitzschia in tidal fresh and estuarine portions of the Manokin River system; to determine the concentrations of domoic acid in the Manokin River system; and to correlate the occurrence of domoic acid with diatom numbers and distribution, and to correlate the number and distribution of diatoms with the concentrations of urea in the system. Ultimately, the intent is to model the varying factors to determine the degree of risk associated with the use of urea or chicken litter as fertilizers.

    FUNDING:  NIFA Capacity Building Grant

    CONTACT:  Dr. Eric May, Distinguished Research Scientist, Department of Natural Sciences, ebmay@umes.edu