The impact of APOE4 on neurological symptoms after exposure to K. brevis neurotoxin

Introduction: The harmful alga Karenia brevis (K. brevis) releases brevetoxins (PbTx) that cause respiratory and neurological symptoms. The apolipoprotein E (APOE) ε4 allele has been linked to poor neurological outcomes after exposure to environmental toxicants. This study explores the influence of the ε4 allele on the relationship between K. brevis in coastal waters and neurological symptoms reported by Southwest Florida residents.

Methods: A Surrogate Brevetoxin Exposure (SBE_air) index was developed to estimate aerosolized PbTx exposure. Data on past medical history and symptoms and blood for analyzing APOE genotypes were collected from 244 participants.

Results: Compared to non-carriers, ε4 carriers more frequently reported experiencing memory problems and fatigue during red tide blooms, independent of conditions like dementia and chronic fatigue syndrome.

Conclusion: This study suggests that the ε4 allele may exacerbate neurological symptoms from aerosolized PbTx, highlighting the need for strategies to better understand the impact of PbTx on the brain.