The latest water measurements at the NEMO Observatory site where the Environmental Sample Processor is located 13 miles off La Push, Washington. Data are updated in near-real time. These products are provided to help understand where toxic algae may be moving and the conditions that may influence toxic blooms.

Domoic Acid Concentration

Concentration of particulate domoic acid in seawater. Domoic acid is a toxin produced by some species of phytoplankton in the genus Pseudo-nitzschia. If domoic acid concentrations are detected above the Lower Limit Of Quantification (LLOQ, see description below), this means that one or more Pseudo-nitzschia species are producing the toxin. There is no regulatory threshold for domoic acid in seawater, rather the toxin is regulated based on its concentration in the tissues of shellfish where 20 ppm is a "no-harvest" limit (see the Washington State Department of Health Beach Closures site). However, a high seawater domoic acid concentration may provide an early warning of a HAB event.

Description of the Terms

Quantifiable: Sensor returned a positive value that could be quantified reliably.

≥ULOQ: Value is greater than or equal to the Upper Limit Of Quantification. Value is above the sensor's ability to quantify reliably; true value is greater than the value reported by some unknown amount.

LLOQ: Value is the Lower Limit of Quantification. LLOQ represents the lowest value that the sensor is able to reliably quantify.

LLOD < y < LLOQ: Value is greater than the Lower Limit Of Detection but less than the Lower Limit Of Quantification; value could range from the LLOD to the LLOQ value. The value reported represents the average fo the LLOD and LLOQ values for that sample.

≤LLOD: Value is below or equal to the Lower Limit Of Detection; value could range from zero to the LLOD. The LLOD represents the sensor's ability to return a positive value.