Accumulation of microcystins in water and economic fish in Phayao Lake, and fish ponds along the Ing River tributary in Chiang Rai, Thailand

摘要: This study determined the levels of microcystins in water and fish from Phayao Lake, Province and selected ponds along the Ing River tributary Chiang Rai Province. Samples were collected monthly for 8 months (January to August 2011 Phayao Lake, November 2008 June 2009 ponds) analyzed by HPLC. The highest total microcystin-LR Lake were recorded April 2010 at 2.60 ± 2.48 μg·L-1 0.20 0.03 μg·kg-1 dry weight, respectively. Microcystis aeruginosa Kutz dominant species (271.6 72.4 mm3/m3) in lake. Colony number Microcystis spp showed a positive correlation with soluble orthophosphate (r2 = 0.77). Similarly, Nile tilapia surveyed contaminated with microcystins as well. The concentration detected was March 2009 (0.58 0.24 μg·L-1), whilst maximum recorded (2.68 0.51 μg·kg-1 weight). spp. dominated pond waters positively correlated with chlorophyll (r2=0.80) and nitrate (r2=0.71). highest concentration cyanobacteria February 4272.5 62.3 mm3/m3. Results that concentration in higher than Lake. suggested the possible health risks associated bioaccumulation microcystins in (Nile tilapia) cultivated Chiang Rai