Introduction: Cyanobacteria, Cyanotoxins, Their Human Impact, and Risk Management

Although recognised as cosmopolitan, ancient inhabitants of aquatic and terrestrial environments with major involvement in global nutrient cycling, cyanobacteria also present economic, supply, aesthetic, and health problems in the availability of water resources for human and animal use. Cyanobacterial hazards to human and animal health are presented by a wide array of toxins (cyanotoxins). These include long-recognised cyanotoxins with causative actions in investigated waterborne health incidents. Exposure media and routes via which such incidents can occur are summarised. Novel cyanobacterial toxic compounds are also emerging and are a focus of current research. Increasing human demands on water resources, for industry, agriculture, aquaculture, recreation, and domestic uses, plus likely effects of climate change, are leading to increased problems with toxigenic, cyanobacterial mass populations. The effective risk management of such cyanobacterial problems requires feasible, robust methods for the monitoring and analysis of cyanobacteria and cyanotoxins, the subject of this handbook.