Evidence of microcystin bioaccumulation and its effects on structural alterations in various shrimp ( Litopenaeus vannamei Boone, 1931) tissues from shrimp aquaculture in the northern coastal region of East Java']Java, Indonesia

Microcystins are generated by diverse cyanobacteria in shrimp ponds marked by high nutrient levels. The study examined microcystin-leucine arginine (MC-LR) in the pond water, gills, hepatopancreas, and muscle of shrimp ( Litopenaeus vannamei) from shrimp ponds on the northern coast of East Java and its effects on their histological structures. In shrimp ponds dominated by cyanobacteria particularly Microcystis and Oscillatoria, MC-LR levels were high. In pond water, Microcystis and Oscillatoria levels increased along with NO2-, NH4+, clarity, and salinity. Shrimp tissues, such as the gills and hepatopancreas, experienced elevated MC-LR concentrations as a consequence of the MC-LR toxin increase in pond water. Shrimp inhabitants of ponds with elevated MC-LR concentrations exhibited significant changes in histological architecture, like hyperplasia in gill tissue and extensive vacuolation in hepatopancreas tissue. L. vannamei muscle samples show MC-LR amounts below the WHO's recommended daily intake of 0.04 mu g/kg body weight/day, indicating no health risks to humans.