Red Tide And Human Health: Researchers Study 'Chronic Exposure'

Nov 14, 2019
Originally published on November 14, 2019 10:00 am

Toxic red tide algae is starting to bloom along Florida’s west coast again. State wildlife officials say elevated levels have been detected recently from Pinellas to Collier counties, and people in Sarasota County have also been experiencing respiratory irritations.

Now, new research is looking into longterm health effects of the toxins, including neurological issues.

On a sunny October day, clear waves foam up and roll onto the white sand of Siesta Key Beach. People are swimming, tanning and jogging -- not a sight seen this time last year, when people were coughing, eyes watering, and dead fish were stinking for miles.

Barbara Kirkpatrick lives just down the road. She’s a scientist who’s been studying red tide and how it affects people for two decades. A study she led back in 2001 examined asthma patients over a span of 10 years.

“The aerosolized red tide toxin is a trigger for their asthma and just a one-hour walk on the beach during a red tide, people had symptoms for three to five days after that one-hour walk on the beach,” said Kirkpatrick.

One of her patients was Allison Pederson, who, at the time, lived about seven miles inland near Bradenton. Pederson now lives in South Carolina.

“My running partner and I, we would choose running paths along the beach and the water. There was a really nice overpass that went over the bay that we always did,” she said. “I started noticing that other than the exercise induced asthma that I had, that it would get worse.”

Pederson describes a regular asthma attack as feeling like a fist wrapping around her lungs, making it hard to breathe.

RELATED: Red Tide-Related Fish Kills Now In Five Florida Counties

“When I'd have issues from the red tide, it would be more of … like a burning, tingling sensation,” she said. “When I’d take a breath, it didn't feel good, and that in turn would kind of cause the wheezing and make it a little harder to catch my breath.”

Pederson would also get headaches, but since moving north, she’s very rarely had any issues. She is curious, though, about the longterm health effects of algae toxins to which she’s been exposed.

Roskamp Institute in Sarasota is studying just that. It's collecting blood and urine samples after some patients also reported headaches and other symptoms during the last red tide event.

“One of the underlying questions here is: can the neurotoxins create inflammation in the brain? Let's hope that they can't, but if they can, we need to know about that,” said Dr. Michael Mullan, executive director of Roskamp.

The Institute is building a bank of people’s fluids from before and after red tide events that it hopes to share with other researchers.

“Remarkably, there are really no longterm exposure data or effects of exposure collected anywhere,” said Mullan. “This is the beginning I hope of a more substantial database and a biobank, in that regard. It really needs to be done.”

Mullan joined researchers from Mote Marine Laboratory and Sarasota Memorial Hospital at a press conference this summer, where Congressman Vern Buchanan, R-Sarasota, announced an over $6 million proposal to fund human health research like this.

RELATED: Congress Funds Red Tide Human Health Research

Kirkpatrick said she’s working with Roskamp Institute on its new database, using one of her old studies.

“So we actually reran the data looking specifically at headache as a diagnosis code,” she said. “And indeed it…was identified and especially in the older population, which of course we have here in our area.”

Kirkpatrick is on the state's Harmful Algal Bloom Task Force which first met in St. Petersburg in September. The group discussed funding for this issue of “chronic exposure” to red tide. Kirkpatrick hopes they can identify science gaps that have not yet been funded.

RELATED: Florida's Algae Task Force Holds Its First Meeting

“It has been a roller coaster. We usually see an uptick of funding when we've had a red tide. And then if we go for a year or maybe we get lucky and go couple years with no red tide, guess what? The funding disappears,” she said.

Now as red tide creeps back up the west coast, it's an ideal time to secure funding that could lead to a breakthrough in human health research.

The task force on red tide meets again Dec. 10 to discuss funding.

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