General Info: Background

Cyanobacteria (blue-green algae) have been recognised in previous IHP projects as opportunistic, nuisance and frequently toxic microorganisms, which adversely affect human water resources and health (1-4). They develop annually in fresh-, brackish and marine waters on a global basis, producing mass populations (blooms, scums, mats) which cause taste and odour problems, drinking water treatment difficulties, loss of recreational and tourist amenities, and present substantial hazards to human and animal health.

Human health effects attributable to cyanobacterial mass populations and the toxins, which they commonly produce, include skin irritations, acute illness and deaths (5, 6). Examples of such human and/or animal illnesses or deaths are available from Europe, N. and S. America, Africa, Asia and Australasia.

Awareness of these problems, and the availability of expertise for their investigation and control, are, however, highly variable throughout the world. For example, a case of over 50 human deaths in Caruaru, Brazil, in 1996 due to exposure of haemodialysis patients to waterborne cyanobacterial hepatotoxins occurred in an environment of low scientific, medical and social recognition of cyanobacterial toxin health hazards, and without adequate analytical capabilities or contingency plans. These deficiencies are to a large extent avoidable, since the necessary knowledge and expertise are relatively well developed in some parts of the world. This proposal aims to set up a global network to collate data from monitoring and current research, to make available model plans of proven effectiveness, and to disseminate the benefits with minimum delay, to human society.