Maine CDC Press Release

July 9, 2010

Paralytic Shellfish Poisoning (Red Tide) Reminder

Augusta - With elevated levels of paralytic shellfish poisoning (PSP, also known as red tide poisoning) causing many areas of the coastline to be closed to commercial harvesting for some shellfish, and with especially high levels detected recently in the Downeast area of the state, Maine CDC in the Department of Health and Human Services and the Maine Department of Marine Resources are reminding Mainers and tourists of recommendations for the safe consumption of shellfish.

Important steps people can take to thoroughly and safely enjoy Maine shellfish include:

  1. Purchase shellfish from a certified shellfish dealer. Their operations undergo rigorous public health screening and auditing.
  2. If harvesting for personal use, make sure the shellfish beds are not closed for red tide. Check the Department of Marine Resources’ website for the latest information on closed areas:
  3. Do not consume clams or mussels floating in ocean waters. They are likely to have filtered much more algae-containing water than those from flats or beds, and therefore will usually have much higher concentrations of toxin.
  4. When eating lobster, do not eat the tomalley.

Advisories against eating tomalley have been in effect for years in Maine, neighboring states, and by U.S. Food and Drug Administration (FDA), mostly due to the presence of PCB toxins, and more recently due to PSP. It is important to note that testing has shown lobster meat is safe to eat. Tomalley is the soft, green substance found in the body cavity of the lobster and functions as the liver. Much like the liver of other animals, the tomalley serves as a natural filter for contaminants that are in the water.

Paralytic shellfish poisoning is a marine biotoxin that is associated with certain types of algae blooms in coastal waters. Bivalve shellfish such as clams, mussels, oysters, and quahogs filter water and eat the toxic algae from the water. High concentrations of the toxin in these types of shellfish can then cause serious illness or even death if eaten by humans.

Although it had been about 30 years since the last report of Mainers with red tide poisoning, the state has seen three serious but non-fatal incidents in the past three years (one each in 2007, 2008, and 2009), involving a total of eight people. All three incidents involved people from Downeast Maine consuming mussels harvested for personal use, and one involved mussels growing off from a rope or barrel floating in the ocean in areas closed for shellfish harvesting because of red tide.

Symptoms of Paralytic Shellfish Poisoning Symptoms of PSP usually include tingling of the tongue, lips, and throat that begin within minutes to 10 hours (usually within 2 hours) of eating shellfish. This tingling may spread to other areas of the body such as the face, neck, and arms. Symptoms can also include headache or nausea, and can progress to weakness, difficulty breathing, and choking. It is important that people with these symptoms seek medical care immediately.

Shellfish that may be unsafe: Clams (soft shell, hard shell, surf, or hen); Mussels; Oysters (both American and European); Quahogs; Snails; and Whelks.

Fish that are usually safe (please call the Poison Center to check, this list is not all-inclusive): Crab (meat, not whole crabs); Lobster (but not the tomalley); Scallop meats; Shrimp; and Finfish.


Maine Department of Marine Resources Red Tide Closures:

Maine CDC/DHHS Red Tide Information:

FDA Tomalley Consumption Advisory