ASP Biotoxins

Eating contaminated Shellfish can be life threatening: Always check for

Bivalve Shellfish

Biotoxin (PSP, ASP, DSP) and Sanitary (Emergency, Seasonal, Annual)

Contamination Closures if you

plan on harvesting and consuming any shellfish.

Go to the latest Biotoxin Contamination update

Attention:

Cooking does not destroy this toxin.

Agent: Domoic Acid (ASP)

Classification: Marine Biotoxin

Fish Species Most Affected:

Most of the toxin within shellfish is normally found within the

digestive gland.

Properties of Agents Relevant to Fish Products or Illness

Filter feeding shellfish feed on small fragments of organic matter

which they filter from the sea water, including small plants or animals.

Some of the small plants (phytoplankton) contain toxins.

Pseudo-nitzschia species (including P. australis) are sources

of domoic acid on the west coast of Canada. It appears the

Pseudo-nitzschia species blooms are periodic; they do not occur every

year even though the organisms are apparently frequently present in the

seawater.

These toxins are heat stable (cooking and boiling does NOT

destroy the toxin).

Characteristic Illness

Amnesic shellfish poisoning is caused by the

ingestion of toxin-contaminated bivalve shellfish and crustaceans.

Algal

blooms usually occur during the warmer months from June to October, but

can also be present any time of the year.

Symptoms

nausea

vomiting

diarrhea

short term memory loss

temporary or permanent brain damage

death

ASP symptoms occur fairly rapidly beginning between 30 minutes to

6 hours after eating contaminated shellfish. If the poisoning is not

severe and the individual is not otherwise compromised (e.g., kidney

problems), they normally recover completely within a few days.

Unfortunately, if the poisoning is severe enough or the individual is

not able to excrete domoic acid readily, temporary or permanent brain

damage may occur. The syndrome is complex but the most notable simple

characteristic is a loss of short term memory, which is why the toxin is

sometimes called Amnesic Shellfish Poison (ASP). If you suspect you have

a severe case of ASP or should problems persist you should immediately

seek medical attention.

At the first sign of such symptoms, contact your

medical attention immediately.

Control Measures

The single most

effective control measure is responsible harvesting, i.e. to ensure that

molluscan bivalve shellfish come only from open harvest areas.

Check to ensure that the area where you intend to harvest is open,

immediately prior to harvesting,

Call before you harvest
Information is

also available on the Fishery Report Record Line at: 1-866-431-3474.

For

more information, please visit the

Canadian Shellfish Sanitation Program page (Canadian Food Inspection

Agency site)

Shellfish Contamination Links

Shellfish Contamination Home

ASP Biotoxins