The two agencies perform weekly monitoring at six zones for the outside coast, as well as inland waters. Domoic acid, caused by microscopic marine diatoms, can sometimes lead to severe illness resulting from human consumption. Symptoms range from vomiting and abdominal cramps to neurological symptoms such as headaches, dizziness and memory loss. Cooking or freezing clams does not lessen toxicity. He said that although domoic acid levels can vary between different areas of the coastline, the overall trend currently shows a downward slide in acid levels.
Razor clams accumulate the toxin and retain it in the edible tissue.
Domoic acid levels can rapidly rise due to the clam's inability to efficiently purify the toxin. Crabs that ingest the toxin by feeding on razor clams are able to get rid of the toxin in a shorter amount of time, flushing it from their digestive systems in a matter of days. This flushing ability is what allows crabs to be safe for human consumption despite the unusually high toxin levels found in razor clams, said Simons. Although the current levels in crab remain safe, officials remain cautious. Cox stated that the unlikely scenario could arise where the season would have to be stopped due to toxin levels, but presently domoic acid levels have not reached the 15 ppm threshold.