Ans: Anabaena can create a variety of toxins, including anatoxin and microcystin. Small amounts of toxin can cause gastrointestinal distress if consumed. If the algal toxin microcystin is present in high concentrations in the water and consumed, severe liver damage can occur. Conjunctivitis, rhinitis, earache, sore throat, and swollen lips may all be symptoms of exposure. Atypical pneumonia and a hay fever-like illness are two respiratory side effects. Electrolyte imbalances, headaches, malaise, and muscle weakness/pain in joints and limbs are all possible side effects of exposure.