The goals of this project are to study the biological effects of environmental toxins (ET), in particular aquatic toxins such as brevetoxins (PbTx) and microcystin or their metabolites. This study is designed to examine the effects of the body from harmful algae blooms (HAB) as well as possibility of an association between exposure to the marine toxin, brevetoxin (PbTx), which is released from K. brevis during the red tide bloom, and the prevalence of neurological illnesses.

Exposure to environmental toxins present in local waters, such as brevetoxins released by Karenia brevis (K. brevis) or microcystin produced by cyanobacteria, is known to cause skin and eye irritation, gastrointestinal and respiratory distress. The ingestion of high levels of brevetoxins from eating contaminated shellfish can result in Neurotoxic Shellfish Poisoning (NSP), an acute gastroenteritis with accompanying neurologic symptoms. People are often exposed by direct skin contact with contaminated waters, drinking contaminated water, breathing in airborne droplets of the toxins, or eating contaminated shellfish. This condition usually resolves itself within 3 days as the brevetoxins are excreted from the body. Aerosolized brevetoxins are also known to cause a reversible upper respiratory syndrome, characterized by coughing, sneezing, and feelings of irritation to the airways. Once the exposure to the brevetoxin-laden air has ceased, symptoms usually go away within 15 minutes.

The main objective of this study is to determine if exposure to marine or similar environmental toxins can adversely affect CNS health, immune system, respiratory system and other biological processes which contribute to long-term cognitive dysfunction or illnesses in individuals exposed to these toxins.

Sponsor will be examining whether general health signs and symptoms that are reported are as associated with the exposure to harmful algal bloom toxins. Known symptoms of exposure to harmful algae bloom/red tide /shellfish include the following: Skin and eye irritation, gastrointestinal and respiratory distress, acute gastroenteritis with accompanying neurologic symptoms, respiratory distress, such as reversible upper respiratory syndrome with symptoms of coughing, sneezing, and feelings of irritation to the airways.

Inclusion Criteria:

1. Subject should be able to provide written informed consent.
2. Adult aged 18 or older.
3. Resident (temporary or permanent) of one of the following five southwest Florida counties (Lee, Collier, Charlotte, Sarasota, or Manatee).
4. Any race or ethnicity.
5. Willing to return for at least a total of four study visits and participate in all required procedures for the duration of the study.

Exclusion Criteria:

1. Inability to speak or write in English.
2. Any medical condition for which the study investigator believes enrollment is medically inappropriate.
3. Unwilling/unable to provide biological samples or poor venous access.

People who have been likely exposed to marine toxins (based on the areas that they frequent) as well as individuals who are unlikely to have been exposed will be recruited. Also, residents (temporary or permanent) of one of the following five southwest Florida counties (Lee, Collier, Charlotte, Sarasota, or Manatee).