The Oregon Department of Agriculture announced today that beaches from the south jetty of the 
Columbia River to Neptune State Park, south of Yachats, have been closed to recreational mussel harvesting due to the presence of paralytic shellfish poisoning (PSP) toxins in those areas. According to the ODA news release concerning the unsafe mussels:
Shellfish contaminated with PSP toxins can cause minor to severe illness or even death. The symptoms usually begin with tingling of the mouth and tongue. Severe poisoning can result in dizziness, numbness and tingling in the arms and legs, paralysis of the arms and legs, and paralysis of the muscles used for breathing. Shellfish toxins are produced by algae and usually originate in the ocean.
In addition to muscles, ODA recommends that recreational shellfish harvesters not consume whole scallops.
The Washington Department of Health explains PSP poisoning associated with “red tide” on its Website. According to WDOH, the amount of PSP toxin emitted from algae into the water increases when water conditions are favorable, but the exact combination of conditions that cause PSP levels to increase is not known. Unlike with bacterial contaminants like vibrio, warm water conditions do not necessarily increase the level of PSP toxins in the water.
A reminder to recreational shellfish harvesters: Always check with the appropriate authorities before consuming shellfish that has been harvested from areas that could be impacted by PSPs or other pathogens.