Bioaccumulation and retention kinetics of cesium in the Milkfish Chanos chanos from Jakarta Bay

• Operation of Nuclear Research Reactor at Serpong can release 137Cs to Jakarta Bay.
• Some areas of the Jakarta Bay have aquaculture ponds.
• The milkfish Chanos chanos can accumulate 137Cs.

Laboratory radiotracer experiments were conducted to study the uptake, assimilation, and retention of cesium (137Cs) in milkfish (Chanos chanos) from Jakarta Bay. In this study, we have examined the bioaccumulation and distribution of 137Cs in C. chanos obtained from 137Cs-labeled seawater and 137Cs-labeled Artemia sp. feeding. The uptake of 137Cs via seawater displayed a one-compartment model suggesting that the concentration factors of 137Cs within the milkfish (weight 2.46–9.86 g) at a steady-state period were between 10.66 and 3.98 mL g− 1 after 10 days of exposure. The depuration rate was observed to be low, with only 22.80–49.14% of 137Cs absorbed by C. chanos, which was absent 6 days after exposure. By contrast, depuration occurred quickly for radiolabeled food uptake, reaching 20% of retention within 10 days after exposure. Muscles and viscera of the milkfish exhibited the highest degree of end uptake and end depuration of 137Cs from seawater and feeding.