PASCO COUNTY, Fla. — FWC has temporarily closed Pasco County to scalloping because of high levels of an organism in the water that can make certain shellfish dangerous to eat.

High levels of Pyrodinium bahamense were found during routine water testing, FWC confirms. Pyrodinium bahamense is a small, single-cell plant that when it blooms in large amounts can produce saxitoxin and cause paralytic shellfish poisoning.

What You Need To Know

  • The waters south of the Hernando-Pasco county line and north of the Anclote Key Lighthouse, including the Anclote River are closed to scalloping 

  • Pyrodinium bahamanse levels have exceeded the safety threshold 

  • When Pyrodinium bahamanse blooms in large amounts, it can produce saxitoxin and cause paralytic shellfish poisoning

  • Symptoms include tingling, headache, difficulty breathing and stomach upset
  • SEE ALSO: Florida boat captains fear loss of business after scallop season put on pause

Steven Murawski, a professor in the College of Marine Science at University of South Florida, says there’s likely no singular cause as to what perpetuated this toxic bloom.

“It’s a plant, and if you have a rush of nutrients into the water — it's been very rainy as of late and the rainy season is upon us — so if you have a lot of rain flushing out nutrients from the land, it can be like fertilizer,” he said.

Saxitoxins have no taste and are small and cannot be destroyed by cooking, according to the FWC. If you eat an affected scallop, you could start feeling symptoms in as little as 15 minutes.

Possible symptoms of Paralytic Shellfish Poisoning include e numbness and tingling of the mouth or hands, dizziness, weakness, nausea, vomiting, respiratory distress, drowsiness, loss of body movement control, headache, tingling sensations in the face and/or extremities, muscle weakness and incoherent speech.

The waters off Pasco County are still open to boating, swimming and fishing.

“Because this is a plant, you’re not likely to be consuming high enough levels of that even by swallowing a little bit of seawater as opposed to a mollusk like the scallop is concentrating all those,” Murawski explained. “This is their food, so they concentrate and pump a lot of water, so it becomes a source of relatively high levels of this.”

Last year's 37-day season brought in more than 43,000 people and a total impact of more than $11 million, according to Florida's Sports Coast. This season was scheduled to last for 40 days.

Pasco County will reopen for scallop harvesting once FWC tests show levels have decreased to safe limits. As of right now, the season lasts until Aug. 18.