We are expanding algal toxin testing to include tests for saxitoxins and anatoxin-a. The new tool will give water managers and community-based monitoring networks the ability to rapidly quantify these cyanotoxins.

Why We Care
Harmful algal blooms (HABs) are a significant threat to fresh waters globally. Cyanobacterial HABs contribute to more than $2 billion in annual U.S. economic losses, and the estimated annual cost of cyanobacterial HABs in western Lake Erie alone exceeds $65 million. Cyanobacterial HABs necessitate routine testing to protect humans from exposure to contaminated drinking and recreational waters and for forecasting and modeling. Since toxin profiles change spatially and temporally there is significant need for rapid tests that can provide real-time, local answers.

The four toxins that are typically monitored in freshwater are microcystins, cylindrospermopsins, saxitoxins, and anatoxin-a. While commercially available semi-quantitative and fully quantitative field test kits exist for microcystins and cylindrospermopsins, there is currently no method for measuring saxitoxins in freshwaters in the field and only a semi-quantitative test strip for anatoxin-a. This is concerning as saxitoxins have been documented in freshwater sources in the U.S. and worldwide, and the frequency and distribution of saxitoxins-producing cyanobacterial HABs have been on the rise. Furthermore, anatoxin-a has been detected in western Lake Erie.

While these toxins have been detected throughout the Great Lakes, currently the only way to collect quantitative data for saxitoxins and anatoxin-a is to have the samples collected and delivered to a laboratory for testing. The delay of laboratory analysis can unnecessarily expose people to toxins while testing is being conducted. Also, performing multiple separate tests is time consuming, expensive, and occasionally necessitates making decisions that reduce the amount of testing. A rapid and portable multiplexed test would reduce the time and cost associated with collecting critical data, while improving human safety by ensuring that all four toxins are always monitored.

We We Are Doing
LightDeck’s patented LightDeck® technology enables portable, multiplexed detection of toxins and has been demonstrated in a commercially available duplex microcystins/cylindrospermopsins panel. This project will expand this toxin testing panel to include tests for saxitoxins and anatoxin-a. This work is novel, as there is no commercially available portable freshwater test for saxitoxins, and there is no 4-plex test available for freshwater cyanotoxins. The 4-plex panel would change the testing paradigms for freshwater by significantly reducing the testing burden and enabling rapid decision making to protect public safety.

The project team will develop saxitoxins and anatoxin-a assays, demonstrate adequate congener coverage and sensitivity, and multiplex the assays into a 4-plex panel with microcystins and cylindrospermopsins. The team will test a field-portable method of lysing cells that produce these cyanotoxins. The 4-plex assay will be validated with certified reference materials and tested with cell culture extracts and natural water samples. End users include researchers, water utilities, water resource managers, environmental stewards, public health managers, and citizen scientists. These groups will use the MBio HAB Quad-Toxin System to better manage water resources and make on-the-spot decisions about public safety.

Dr. Sarah Bickman of LightDeck Diagnostics leads this project. Co-investigators are Drs. Timothy Davis (Bowling Green State University), and Gregory Boyer (State University of New York). The project is funded through the NCCOS Prevention, Control, and Mitigation of Harmful Algal Blooms Program.