October 14, 2005
The Texas Department of State Health Services (DSHS) is reminding people not to harvest and eat oysters, clams, mussels or whelks from Texas coastal waters because of red tide, an algae bloom. The warning does not apply to shrimp, finfish, crabs, commercially harvested oysters from Galveston Bay or to commercial seafood products from other states or countries.
The algae contain a toxin that can accumulate in the tissue of oysters, clams, mussels and whelks and cause neurotoxic shellfish poisoning, or NSP, in humans who consume them. NSP symptoms can include nausea, dizziness, dilated pupils and tingling sensations in the extremities.
The red tide toxin can become aerosolized and cause coughing and irritation of the throat and eyes. People with respiratory conditions such as asthma may experience more pronounced symptoms. Respiratory symptoms usually subside when affected people leave the red tide areas.
DSHS officials said red tide has been observed in the Lower Laguna Madre, South Padre Island, Port Mansfield and Corpus Christi Bay areas.
However, all Texas coastal water is closed to the harvesting of oysters, clams and mussels, except for the commercial oyster harvesting in Galveston Bay.
Open season for oysters begins Nov. 1 each year, but DSHS officials said the opening could be delayed in affected areas this year because the toxin can remain in oyster tissue for several weeks.
Red tide updates can be found on the Texas Parks and Wildlife Department Web site, www.tpwd.state.tx.us/landwater/water/environconcerns/hab/redtide/.
(News Media: for more information contact Kirk Wiles, DSHS Seafood and Aquatic Life Group, at 512-834-6757; or Doug McBride, DSHS Press Officer, 512-458-7524.)