Lawrence Livermore National Laboratory (LLNL) scientists and collaborators have used a new technique to better forecast the level of algal toxins that accumulate in Lake Erie every year, an advancement that could benefit water treatment plants.

Harmful algal blooms (HABs) are caused by cyanobacteria that produce microcystins, a suite of amino-acid-like toxins that are harmful to humans. Cyanobacterial biomass forecasts in Lake Erie – which has a history of HABs – are made possible with frequent remote sensing data and lake water mass movement. One of the more widely known forecasts uses satellite images of Lake Erie to forecast cyanobacteria location and biomass two to four days in advance. While the biomass forecasts have aided managers in predicting when and where the cyanobacterial blooms will be located, the forecasts cannot currently predict microcystin concentrations because toxicity is not always correlated with biomass. To help provide more accurate predictions, the team used isotope labeling of the cyanotoxins to examine its degradation in Lake Erie. They confirmed that a small but highly active component of the microbiome was responsible for the degradation of the toxin. Study co-author Thomas Bridgeman, from the University of Toledo’s Lake Erie Center, explained, “We have been measuring microcystin concentrations in Lake Erie for many years, but this study is the first to show that the toxin levels we measure on any given day are the net result of competing microcystin production and degradation processes that vary over time and space. It’s a big step towards the development of models that will be able to produce microcystin forecasts for the benefit of water-treatment plants and recreational users of Lake Erie.” Read more at LLNL.