In a nutshell: Shellfish harvested and recalled from Texas bays may cause a diarrhea like condition.
March 7, 2008–The Texas Department of State Health Services (DSHS) has closed Aransas, Corpus Christi and Copano bays to shellfish harvesting and has issued a recall of oysters, clams and mussels because of an algae bloom.
DSHS officials say high concentrations of the Dinophysis organism have been found in several locations in the area. The toxin produced by this algae bloom, okadaic acid, can accumulate in shellfish tissue and cause diarrhetic shellfish poisoning, or DSP, in people who consume oysters, clams or mussels. Cooking does not destroy the toxin.
Shellfish harvested from these bays on March 1 or later are included in the recall.
Consumers who purchased shellfish March 1 or later are advised not to eat them. People should either call the store where the shellfish were purchased to determine the date and location of harvest or dispose of them. The toxin does not affect other seafood.
DSHS officials say that preliminary test results indicate that levels of okadaic acid in oyster samples taken from the bays exceed federal guidelines. Final test results will be available next week. DSHS will monitor and determine when it is safe to reopen the shellfish areas.
DSP symptoms include vomiting, diarrhea, nausea and cramping. Symptoms, which usually last two to three days, can begin from 30 minutes to 12 hours after eating shellfish containing the toxin. DSP usually is not life threatening and does not generally cause long-term effects. DSHS is not aware of any illnesses associated with this algae bloom.
Dinophysis occurs naturally in ocean waters and estuaries and is not related to pollution. Typically it is not found in high numbers along the Texas Gulf Coast. High concentrations can turn the water an orange or brown color. DSHS officials say they know of no health issues associated with people being in water containing the algae.