Bioaccumulation of microcystins (MCs) in four fish species from Lake Taihu, China: Assessment of risks to humans

Abstract

Microcystins (MCs) are the toxic products of harmful algal blooms and they accumulate in fish. The accumulation of MCs in fish living in different trophic levels from different parts of Lake Taihu was determined. This information was then used to evaluate the risks posed by the MCs in fish to human health. The concentrations of three MCs, MC-LR, MC-YR and MC-RR, were quantified in the following four fish species: silver carp (Hypophthalmichthys molitrix), bighead carp (Aristichthys nobilis), crucian carp (Carassius auratus) and common carp (Cyprinus carpio), using high performance liquid chromatography interfaced with tandem (triple quadrupole) mass spectrometry. The mean concentrations of MCs in the muscle, the kidney, the intestinal wall and the heart were significantly different among the four fishes except in the liver. C. carpio contained the highest mean concentration of MCs in the muscle (31.7 ± 12.1 ng/g, dry mass (dm)), whereas C. auratus had the highest mean concentrations of MCs in the liver (45.4 ± 44.5 ng/g, dm), kidney (114 ± 51.1 ng/g, dm), intestinal wall (2.04 × 10 3 ± 4.43 × 10 3 ng/g, dm) and heart (59.5 ± 26.7 ng/g, dm). The mean concentration of MCs in the intestinal walls of the fish species was significantly higher than in other organs (p b 0.01). The fish from Meiliang Bay had significantly higher concentrations of MCs than those from the centre, west or south banks of the lake (p b 0.01). The body lengths and masses of the fish were negatively correlated with the concentrations of MCs in the kidney (p b 0.05) and heart (p b 0.01). The average daily intake (ADI) of MCs in the muscle of all fishes exceeded the provisional tolerable daily intake (TDI) set by World Health Organization. The estimated daily intakes of MCs in 55.6% of the muscle samples exceeded the TDI. The MCs in the tissues of the fish from Lake Taihu pose potential risks to the health of humans who consume these four fish species.

First report on free and covalently bound microcystins in fish and bivalves from Vietnam: Assessment of risks to humans

“…By contrast, the largest proportion of MC‐RR occurred in the intestines of the phytoplanktivorous fish O. niloticus (Figure A), which accumulated a greater concentration of MCs ( p < 0.05) in the intestine than B. gonionotus and P. proctozysron . These results are in accordance with previous studies , thus suggesting that MC accumulation in fish is related to the abundance of cyanobacteria in raw water. In the 2 bivalves, Corbicula sp.…”

“…Table 1 shows the maximum MC contents in fish and bivalves in a field experiment. The maximum contents of MCs in fish and bivalves were 137 and 420 mg g À1 dry weight, respectively [5][6][7][8][9][10][11][12][13][14][15][16][17]. Bivalves tend to accumulate a high amount of MCs because of their filter-feeding function [3].…”

The production and release of microcystin related to phytoplankton biodiversity and water salinity in two cyanobacteria blooming lakes

“…Many Microcystis strains produce microcystins, a prevalent and widespread cyanotoxin with more than 100 variants currently reported (Chorus and Bartram ; Puddick ; Corbel et al ). Microcystins are present in a broad range of aquatic systems (Chorus and Bartram ; Song et al ; Poste et al ; Jia et al ), and are potent hepatotoxins and potential tumor promoters (Falconer and Humpage ; de Figueiredo et al ; Chen et al ). They have been found in the serum of fishermen with liver failure due to long‐term exposure through drinking water and aquatic products (Chen et al ).…”

The toxic effects of microcystin-LR on mouse lungs and alveolar type II epithelial cells

“…MC-LR is chemically stable and has a very slow natural degradation process. Consumption of the fish that living in the water contains MCs may pose potential risks to the health of humans (Jia et al, 2014). MCs have been shown the toxic effects to liver, nerve, kidney and reproductive organs (Funari and Testai, 2008).…”