Using Novel Technology to Examine Trends in Cyanobacterial Toxin Levels

Cyanobacterial harmful algal blooms are ubiquitous globally and can have enormous impacts on the environment, economy, and human health. These blooms have the potential to produce toxins such as microcystin (MC), cylindrospermopsin (CYN), and saxitoxin (STX). Currently, the standard method for toxin testing is by an Enzyme Linked Immunosorbent Assay (ELISA). This method is time consuming; LightDeck Diagnostics has developed a rapid and portable multiplexed assay to simultaneously test for MC, CYN, STX as an alternative to ELISA testing. During the summer of 2021, LightDeck’s duplexed MC-CYN assay was successfully field validated in Sandusky Bay. A method of portable lysis was also tested but is undergoing further development prior to being used in additional testing. During the summer of 2022, a triplexed version of the LightDeck cartridge (MC-CYN-STX) was field validated in both Sandusky Bay and Springbrook Lake in Whitehouse, Ohio. The STX assay successfully detected toxin, however the triplexed MC assay did not perform as well as the previous duplex formulation. Additionally, toxin concentrations were correlated with water quality parameters and nutrients in both lakes to investigate potential environmental drivers of toxicity during bloom events. The LightDeck assay was also used as part of a research cruise in the Winam Gulf, Kenya. Though ELISA remains the gold standard for toxin detection, the LightDeck assay could be a valuable tool in monitoring and reporting toxin in water bodies that people interact with, whether they be recreational lakes or water that the community relies on for daily functions as demonstrated in the case of the Winam Gulf.