The Roskamp Institute, located in Sarasota, opened its doors in 2003 with the purpose of better understanding and treatment of diseases of the mind. They recently issued a report on a study they have done, funded by the National Institute of Environmental Health Sciences, on the neurological impact of red tide toxins. The study was conducted with 250 community volunteers from Sarasota, Manatee, Lee, Charlotte and Collier counties in Florida.
This is what we presently know about red tide. It effects the environment and is responsible for large fish kills. It is one of the leading causes of death of manatees (an endangered species) and blamed for many dolphin deaths. It causes millions of dollars in lost revenue to Florida communities, hotels, restaurants and water-based tourism attractions like fishing and boating. It can cause respiratory symptoms (especially in sensitive populations like asthmatics) and has been implicated in the cause of skin irritations. When contaminated shellfish is consumed, it can cause Neurotoxic Shellfish Poisoning (NSP) with symptoms of nausea, vomiting, diarrhea, numbness and tingling, dizziness, headache and a reversal of hot and cold sensations. It impacts the quality of beach experiences, water recreation and fishing activities.
The new study published by the Roskamp Institute in the peer-reviewed journal Harmful Algae provides new evidence that red tide exposure can have neurological impacts — suggesting for the first time that certain individuals are susceptible to airborne exposure from red tide blooms. In particular, individuals with a previous history of migraine or chronic fatigue syndrome, extreme fatigue that worsens with physical and mental activity, are more likely to have symptoms that have previously only been associated with eating seafood contaminated with red tide toxins. However, participants in this study had only been exposed to red tide toxins in the air.
“During previous studies looking at how red tide toxins affected lung function, study participants sometimes reported headaches and we thought it was important to investigate this further,” said Dr. Laila Abdullah, Research Scientist at the Roskamp Institute. “Building on previous findings, we found that migraine sufferers reported headaches during red tide blooms. However, we did not expect that people would report Neurotoxic Shellfish Posioning-like symptoms,” she said. “Our study also indicates that repeated airborne exposures in otherwise healthy people can also make them more sensitive to red tide.”
Roskamp Institute Executive Director Dr. Michael Mullan, a physician and research scientist said, “different people respond to the toxins in different ways — from not being affected at all to experiencing a range of severe symptoms. We don’t understand why that is the case nor do we know the dose levels of toxins that are needed to cause neurological symptoms. There is still much to understand about this toxin and the levels of threat it poses to human brain health.”
Study co-author Dr. Barbara Kirkpatrick, GCOOS Senior Advisor, and longtime START board member, was one of the lead researchers on the early studies of red tide and human health. “Our work on the human-health impacts of red tide led to our development of the Red Tide Respiratory Forecast [redtideforecast.com], which helps people know which beaches could have red tide impacts throughout the day and lets them know when the best time to visit a particular beach will be. These latest findings indicate that there is much more for us to discover about how humans are impacted by red tide, and we’re hoping to continue building upon this work in future studies.”