Principal Investigators

Dave Hambright, Jessica Beyer (University of Oklahoma)
Keith Loftin (U.S. Geological Survey, Kansas Water Science Center, Lawrence, KS)

in cooperation with:
Julie Chambers (Oklahoma Water Resources Board, Oklahoma City, OK) 

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Project Overview

   Harmful algal blooms, particularly of toxigenic cyanobacteria (cyanoHABs), are a growing threat to human health and our nation’s countless inland water bodies, including over 30,000 reservoirs that serve primarily for domestic water supply and recreation. There is a critical need for a reliable, affordable, broadly adaptable system for detecting cyanoHABs and their toxins early in a bloom cycle to adequately protect the public from exposure to cyanobacterial toxins (cyanotoxins). Moreover, biological understanding of the factors underlying cyanoHAB outbreaks and cyanotoxin production represent major knowledge gaps, as well as obstacles to mitigation of cyanoHABs and public health protection.

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   This monitoring and research program will produce the following deliverables:

i) Multi-tiered evidence for the need to monitor near-shore waters to improve public health risk management.

   Demonstration that cyanoHABs are typically more severe in near-shore waters will provide water managers and public safety officials the ability to better manage public health risk during peak recreation activity that coincides with the summer-fall cyanoHAB period. Current water quality monitoring programs in the South Central US focus primarily on open-water sites, yet our initial evidence (see below) suggests that near-shore sites experience more severe cyanoHABs. Further, recreators are more likely to come in contact with water in the near-shore versus open-water sites, emphasizing the need to track cyanoHABs in these near-shore environments. We will directly compare cyanotoxin concentrations, cyanobacterial abundances, and water quality parameters between existing open-water monitoring sites and new near-shore sites selected to represent areas in which swimmers, boaters, and campers would interact closely with water. We will produce a comprehensive comparison of cyanoHAB abundance and toxin production in near-shore and open-water.

ii) The foundation for a reliable early-warning monitoring program that will greatly reduce risk of cyanotoxin exposure to recreators and their pets, as well as livestock and wildlife.

   Currently, most cyanoHAB monitoring programs are reactive. A proactive program is possible with the incorporation of affordable, reliable, and accurate molecular tools, coupled with targeted analytical chemistry. Knowledge of the specific cyanoHAB taxa present in a system will allow water managers and public safety officials to efficiently monitor for the specific toxins known to be associated with the cyanoHAB taxa forming the bloom, rather than performing sweeping analyses of all possible toxins, or even worse, the more common approach of analyzing only for microcystin, even though the cyanobacterial species forming a bloom may not even be a microcystin producer. For example, a common bloom-former in the South-Central US, Raphidiopsis (formerly Cylindrospermopsis) raciborskii, produces the potent hepatotoxin cylindrospermopsin but not microcystin.

iii) A better understanding of the (micro)biological and environmental agents involved in cyanoHAB formation, and importantly, the production, release, and degradation of cyanotoxins.

   One of the largest knowledge gaps in water quality management is a fundamental understanding of cyanoHAB blooms and their toxins. Recent study has shown that cyanoHABs are not simply a single species dominating the algal community following a surge in nutrient inputs. Rather, cyanoHABs are complex, synergistic communities of bacteria, including one or more abundant photosynthetic cyanobacteria, that together form an interactome. The cyanoHAB interactome undergoes a series of compositional and functional successions from pre- to post-bloom. It has been hypothesized that the associated non-photosynthetic bacteria constitute a microbiome that supports the growth of photosynthetic cyanobacteria during early bloom phases. The microbiome provides vital biochemical pathways not found in cyanobacteria, supplying vitamins, nutrients, and other necessary compounds to the cyanobacteria, while the carbon fixation via photosynthesis by the cyanobacteria provides rich sources of sugars and complex carbohydrates to support bacterial growth. In later bloom phases, the microbiome shifts to a community geared more toward carbon degradation as the cyanobacteria senesce. It is unclear to what extent these bacteria contribute to cyanotoxin production and degradation within the bloom, although it has been shown that some bacteria can breakdown cyanotoxins and may potentially be utilizing them as a food source. The bacterial microbiome could be directly impacting how much toxins are being released into the ecosystem.