Tony Amos, an oceanographer with the UT Marine Science Center, said no one is really sure what causes the red tide algae to bloom to toxic levels. The toxins created by the algae attack the nervous system of fish. But only infected clams, mussels and oysters are unsafe for human consumption. Eating them can cause nausea, dizziness, tingling sensations in the extremities and dilated pupils. Illness can last several days but is not usually fatal.
Airborne toxins caused by red tide also can cause nose, throat and eye irritations.
More than 14 million fish already have died since red tide developed off the Texas coast in September. An outbreak of red tide last year prompted health officials to ban commercial oyster harvesting for several months, creating economic hardships in coastal towns that depend on the business. E.W. Scripps Publications , All Rights Reserved. Site users are subject to our User Agreement . We also have a Privacy Policy .