Simultaneous determination of microcystin contaminations in various vertebrates (fish, turtle, duck and water bird) from a large eutrophic Chinese lake, Lake Taihu, with toxic Microcystis blooms

Abstract

This is the first to conduct simultaneous determination of microcystin (MC) contaminations in multi-groups of vertebrates (fish, turtle, duck and water bird) from Lake Taihu with Microcystis blooms. MCs (-RR, -YR, -LR) in Microcystis scum was 328 μg g − 1 DW. MCs reached 235 μg g − 1 DW in intestinal contents of phytoplanktivorous silver carp, but never exceeded 0.1 μg g − 1 DW in intestinal contents of other animals. The highest MC content in liver of fish was in Carassius auratus (150 ng g − 1 DW), followed by silver carp and Culter ilishaeformis, whereas the lowest was in common carp (3 ng g − 1 DW). In livers of turtle, duck and water bird, MC content ranged from 18 to 30 ng g − 1 DW. High MC level was found in the gonad, egg yolk and egg white of Nycticorax nycticorax and Anas platyrhynchos, suggesting the potential effect of MCs on water bird and duck embryos. High MC contents were identified for the first time in the spleens of N. nycticorax and A. platyrhynchos (6.850 and 9.462 ng g − 1 DW, respectively), indicating a different organotropism of MCs in birds. Lakes with deaths of turtles or water birds in the literatures had a considerably higher MC content in both cyanobacteria and wildlife than Lake Taihu, indicating that toxicity of cyanobacteria may determine accumulation level of MCs and consequently fates of aquatic wildlife.