Polychlorinated biphenyls (PCBs) and Polybrominated Diphenyl ethers (PBDEs) in three fish species from an estuary in the southeastern coast of Brazil

► PBDEs and PCBs in three different fish species were determined. ► PBDEs levels were very low, with values below the limit of quantification. ► PCBs concentrations ranged from 2.29 to 27.60ngg−1ww in muscle and from 3.41 to 34.22ngg−1ww. ► Significant positive correlations were established between PCBs concentrations and fish biometric variables in mullet. ► A statistically significant change between seasons in croaker was observed. Polychlorinated biphenyls (PCBs) and Polybrominated Diphenyls Ethers (PBDEs) are two highly lipophilic classes of persistent organic pollutants able to resist degradation and with the ability to bioaccumulate through the food chain. In Brazil, there are still few studies on PCBs and PBDEs in aquatic organisms. In this study, we determined the levels of PBDEs and PCBs in three different fish species from the Ilha Grande Bay, located in the southern state of Rio de Janeiro, Brazil. PBDEs levels were very low, with values below the limit of quantification. PCBs concentrations ranged from 2.29 to 27.60ngg−1ww in muscle and from 3.41 to 34.22ngg−1ww in liver of the three investigated fish species. Significant positive correlations were established between PCBs concentration and fish biometric variables in mullet (length and lipid content) and a statistically significant change between seasons in croaker was observed.