Related Experiment Video
Updated: Mar 21, 2026

Author Spotlight: Assessment of Environmental and Drug-Induced Behavioral Changes in Adult Zebrafish
Published on: November 3, 2023
Behavioral alterations induced by repeated saxitoxin exposure in drinking water
Felipe Diehl1, Patricia Baptista Ramos2, Juliane Marques Dos Santos2
1Postgraduate Program in Physical, Chemical and Geological Oceanography, Institute of Oceanography, Federal University of Rio Grande (FURG), Rio Grande, RS Brazil ; Institute of Oceanography, Federal University of Rio Grande (FURG), Caixa Postal 474, Rio Grande, RS CEP 96203-900 Brazil.
Background:
Blooms of the saxitoxin-producing cyanobacterium Cylindrospermopsis raciborskii have been contaminating drinking water reservoirs in Brazil for many years. Although acute effects of saxitoxin intoxication are well known, chronic deleterious outcomes caused by repeated saxitoxin exposure still require further investigation. The aim of the present work is to investigate the effects of consumption of drinking water contaminated with C. raciborskii for 30 days on learning and memory processes in rats.
Methods:
The effects of saxitoxin (3 or 9 μg/L STX equivalents) or cyanobacteria on behavior was determined using the open field habituation task, elevated plus maze anxiety model task, inhibitory avoidance task, and referential Morris water maze task.
Results:
No effects of saxitoxin consumption was observed on anxiety and motor exploratory parameters in the elevated plus maze and open field habituation tasks, respectively. However, groups treated with 9 μg/L STX equivalents displayed a decreased memory performance in the inhibitory avoidance and Morris water maze tasks.
Conclusions:
These results suggest an amnesic effect of saxitoxin on aversive and spatial memories.

