Cyanobacteria are photosynthetic prokaryotes that can
have a wide range of habitats such as rivers, lakes,
streams, ponds, marine environments, and even harsh
environments, for example, hot springs. They are a natural
and essential part of the ecosystem, representing the
base of the aquatic food chain. However, increased eutrophication
(e.g., nutrient enrichment) of these water
bodies can lead to a growing trend in the incidence of
cyanobacterial blooms and the production of toxic metabolites.
Cyanobacteria and their potential impact on
human health is an emerging public health issue that has
received increasing scientific interest resulting in new
and ongoing research. This is because cyanobacteria
produce toxins that are potentially capable of causing
disease in humans. The toxins are released into the water
when cyanobacteria die and decay, leading to the deterioration
of the water quality, particularly those used
for recreational and drinking purposes. Therefore, the
occurrence of cyanobacteria and their cyanotoxins not
only pose health hazard to humans and wild animal who
consume contaminated waters, but also represent a threat
to fish and other aquatic organisms found with them in
the same environment.
As most countries, Egypt and Saudi Arabia do not
escape toxic cyanobacterial blooms. So far, few data are
available on the occurrence of toxic cyanobacteria in both
countries, although cyanobacteria may represent a serious
problem for many water bodies used for drinking
and recreational purposes. The first report on the presence
of toxic cyanobacteria in Egypt was in 1993. The
study identified and characterized the hepatotoxins
‘microcystins’ from Microcystis aeruginosa isolated from
the Nile River. Few years later in 1998, a study reported
an M. aeruginosa bloom in an Egyptian fishpond with a
high microcystin content of 1.12 mgg1 dry weight. A
first evaluation of the occurrence of toxic cyanobacteria
in Saudi Arabia was made in agricultural pond in 2002,
but the toxins produced were not identified. Since that
time, the progress in monitoring of cyanobacteria populations
combined with cyanotoxin analysis in water
bodies used for various purposes in both countries increased
during the recent few years. However, such
monitoring programs are at the academic level only and
not reflected at a national governmental level in terms of
the instigation and legislation of these programs.