Abstract:

Eutrophication of freshwater lakes has led to an increase in the occurrence of harmful cyanobacterial
blooms, and it is expected that a warming climate will further exacerbate the frequency and duration of
such blooms. Microcystin is a cyanobacterial hepatotoxin that is found worldwide, and poses a serious
threat to the ecological communities in which it is found as well as to those who use these waters for
drinking, recreation, or as a food source. Although microcystin is known to accumulate in fish and other
aquatic biota, the prevalence of microcystin in fish tissue and the human health risks posed by
microcystin exposure through fish consumption remain poorly resolved. Very few studies have quantified
microcystin (a broadly present cyanotoxin) in water from East African lakes, despite the large human and
animal populations that rely on these lakes for both water and food, and to date there is very little
information available on the accumulation of microcystin in fish from these lakes.