With harmful algal bloom season on the horizon in the Pacific Northwest and Gulf of Maine, environmental and marine scientists with NOAA’s National Centers for Coastal Ocean Science are finalizing the steps in preparing toxin detection sensors that will be deployed in those regions. These sensors are the critical component of Environmental Sample Processors (ESPs) that determines if an algal bloom is harmful. ESP deployments are executed in collaboration with local partners who operate the mechanics, handle the communications, and deploy the instruments, while NCCOS scientists are responsible for the sensors that detect the toxins, as NCCOS possesses the sole capability for this specific toxin-detection method.
NCCOS scientists dial in specific antibody dilutions for both primary and secondary antibodies. The primary antibody is a protein designed specifically to bind with the toxin of interest. The secondary antibody has the necessary enzyme to produce the light measured by an onboard camera. Additionally, NCCOS scientists produce a toxin standard curve (used to quantify the amount of toxin within a sample), and produce toxin arrays on nitrocellulose paper disks (used to determine the presence of toxin) to which the toxins bind. The printed arrays used for the toxin sensor are especially sensitive to heat and humidity. Scientists have to take special care and be vigilant of the conditions within the laboratory environment when preparing the arrays.
For each deployment, NCCOS scientists prepare the sensors to detect specific toxins common to the region in which they are being deployed. For the upcoming deployments, the team is preparing sensors to detect domoic acid, a powerful neurotoxin produced by Pseudo-nitzschia, which causes amnesic shellfish poisoning. It accumulates in seafood and infects humans and wildlife when consumed. The ESPs collect and transmit near real-time data to NCCOS staff who then process the information for each sample. This timely information is then disseminated through bulletins alerting managers who need to inform subsistence and commercial harvesters of the potential for toxin exposure and illness.
Developing these toxin arrays is a collaborative effort. The partners own the ESPs that are deployed, which means they are responsible for maintenance of the instruments, loading of general reagents, setting up the communications both before and during the deployments, and actually deploying the instruments, either from a boat or dockside.
NCCOS provides the capability of detecting toxins within the water. Without NCCOS expertise providing the toxin sensors to outfit the ESPs, partners would be able to launch the instruments and collect water samples that would detect the presence of algal species and collect valuable environmental DNA samples, but they would not have the capability to detect the presence of toxins.
The next step is for the team to travel to partner sites—from which the ESPs will be deployed—to calibrate the instruments using samples containing the targeted toxin and ensure proper functionality.
This effort is conducted in partnership with the Northwest Fisheries Science Center and the University of Washington’s Applied Physics Laboratory on the West Coast, and Woods Hole Oceanographic Institute in the Northeast. The Environmental Sample Processors (ESPs) were originally designed by Monterey Bay Research Institute (MBARI) and are now manufactured by McLane Laboratories.
This work is part of an ongoing project and authorized under the Harmful Algal Bloom and Hypoxia Research and Control Act (33 U.S.C. §§ 4001 et seq.).