Assessment of Environmental and Toxic Risks of Cyanobacteria in Room Reservoir

Abstract

Cyanobacteria occurs in all Syrian reservoirs, and some species have considerable  environmental and health effects especially in blooms periods during late Summer and early Autumn as result to produce toxins (microcystins) (MC^,s) poisonous to human, animals and aquatic organisms, also it produce test-and-odor compounds which cause significant economic and public health concerns. This researchdedicate to determine species of cyanobacteria occurs in Room reservoir in Sweeda during their blooms and detect toxins concentration released, in addition to determine some physical and chemical characteristics of reservoir. The importance of this research comes from absence national studies which illustrate role of cyanobacteria and their effects on public health in Syrian water resources.The resultswere rangedas follows, water temperature (3.5 Cº  in February and 25Cº in July ).Turbidity (3 NTU in August and 150 NTU in October), pH (7.5 in May and 10 in September).Where as, electrical conductivity EC (was 150 µS/cm in October and 240µS/cm in December ), total dissolved solidsTDS (85 mg/l in October and 170 mg/l in December), dissolved oxygen DO (4mg/l in November and 7 mg/l in October ),whilenutrients ions concentrations were nitrate (0.5mg/l in July and 4mg/l in May), sulfate (18mg/l in June and 34 mg/l in November), and phosphate (0.03mg/l in March and 0.7 mg/l in June), Taxonomic study shows 17 genera, and blooms occurs in October and Novemberwhere dominant related to three species Microcystisaeruginosa,Anabaenaspiroides,andAphanizomenonflos-aquae, and the concentration of MC-LR was over standard value of  World Health Organization (WHO)from September to January. The maximum valueof MC-LR was 13 µg/l in October, and water of reservoir is low risk in September, December andJanuary, and moderate risk in October and November. So we recommend to apply a monitoring program of water quality of Syrian water resources and determine periods of cyanobacteria blooms and measuring concentration of toxins in water and make procedures which prevent blooms in surface water.