title: Radiocesium uptake, trophic transfer, and exposure in three estuarine fish with contrasting feeding habits.
abstract: This study investigated the effects of different environmental factors on (137)Cs uptake in three subtropical estuarine fish, and the trophic transfer of (137)Cs in the fish from different preys. Our data showed that salinity, potassium, and temperature had appreciable effects on the dissolved uptake of (137)Cs in the fish, but no conclusive relationship was found between the effects of salinity and potassium concentration on the uptake. The dietary assimilation of (137)Cs was 51-55% in the omnivorous fish Siganus fuscescens when fed with macroalgae or bivalve tissues, and was much lower than those in carnivorous fish Sebastiscus marmoratus and Jarbua terapon (70-79%). Dietary pathway dominated the (137)Cs accumulation in the omnivorous and carnivorous fish, both of which exhibited strong potential to biomagnify (137)Cs from their preys. Using the biokinetic model, we demonstrated that salinity and temperature only had minor effects on the overall accumulation of (137)Cs in carnivorous species living in estuarine environment. Modeling calculation suggested that it would take 37-80 days for the fish to reach 95% of steady-state concentration, and lower somatic growth increased the time to reach steady-state in the fish.
authors: Division of Life Science, The Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong; Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong 518060, China.
authors: Ke
authors: K
authors: Pan
authors: Division of Life Science, The Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong. Electronic address: wwang@ust.hk.
authors: Wen-Xiong
authors: WX
authors: Wang
mesh_terms: D000818:Animals; D001682:Biological Availability; D049872:Bivalvia / Q000737:chemistry*; D002588:Cesium Radioisotopes / Q000378:metabolism*; D004032:Diet; D063366:Estuaries; D005247:Feeding Behavior; D005399:Fishes / Q000378:metabolism*; D007700:Kinetics; D010473:Perciformes / Q000378:metabolism*; D054712:Salinity; D012492:Salts; D012624:Seaweed / Q000737:chemistry; D013045:Species Specificity; D013696:Temperature; D013997:Time Factors
chemical_list: D002588:Cesium Radioisotopes; D012492:Salts
keywords: Cesium; Estuarine fish; Kinetics; Trophic transfer