*10.9. Harmful Algal Blooms (HABs)*

Harmful algal blooms have the potential to increase with changes in climate [75]. The neurotoxin producing dinoflagellate and diatom plankton mainly cause disease through shellfish poisoning and Ciguatera poisoning in fish, but can also be responsible for the mass deaths of fish. Monitoring of shellfish waters can facilitate shellfish bed closures as a means of controlling exposure through food, while ciguatera is mostly controlled by not eating carnivorous reef fish. Blooms can cause respiratory symptoms in people on affected bathing beaches. Freshwater cyanobacteria are a potential risk through untreated potable water, and the toxic products can cause liver disease. In developed countries, these problems should be dealt with by water utilities.
