Water Resources Research Act Program

Details for Project ID 2017AZ576B

Might Recycled Wastewater Solve the Rising Problem of Toxin-Producing Algae?

Institute: Arizona
Year Established: 2017 Start Date: 2017-03-01 End Date: 2018-02-28
Total Federal Funds: $9,463 Total Non-Federal Funds: $18,929

Principal Investigators: Kevin Fitzsimmons, Robert Lynch

Abstract: Cyanobacteria, a phytoplankton phylum found in surface water bodies worldwide, can cause severe aesthetic water quality problems and induce water deoxygenation, leading to fish kills. Furthermore, some cyanobacterial genera, most notably several Microcystis species, are known to produce neurotoxic peptides known as microcystins. Such toxin production is of critical and increasing public health concern, as neurotoxic cyanobacterial algal blooms in freshwater lakes and streams have been implicated in human and animal sickness, and even death, in recent years. Environmental triggers inducing the production of microcystins by algal blooms are poorly understood. Studies have correlated increased toxin production to enhanced temperature, nutrient concentrations, and light intensity, but research results examining microcystin toxin production in response to environmental stimuli have rarely been conclusive outside of the laboratory or over multiple seasons. This has been due, in part, to difficulties inherent in identifying toxin-producing Microcystis bacteria and quantifying potential toxin production. Recent advances in molecular technologies have allowed the development of real-time quantitative PCR assays to detect specific microbial genes in bulk water samples, and this has greatly facilitated the ability to identify and quantify both Cyanobacterial DNA and the toxin synthesase gene (mcyD). This proposal is based on proof-of-concept laboratory work that identified substantial reductions in mcyD genes in recycled municipal wastewater compared to groundwater. We propose to expand this work outside of the lab and into Arizona retention ponds, and to measure specific environmental factors (including temperature, water conductivity, and heavy metal concentrations) that may be reducing toxin synthesis in recycled water retention ponds. This research will result in data that can be utilized in submission of large proposals to Department of Commerce and other funding agencies. Knowledge of the regulation of microcystin toxin biosynthesis would allow implementation of water management strategies to avoid environmental conditions that induce dangerous water quality conditions. In this way, the proposal directly supports WRRA 104b program research priorities of “exploring new ideas that address water problems” and “expanding understanding of…water-related phenomena.” In addition, this work will provide summer salary to a master’s level student, supporting, “the entry of new research scientists…into water resources fields.”