Levels and health risk assessment of heavy metals in dried fish consumed in Bangladesh

As a cheap source of high-quality protein, healthy fats and essential nutrients, dried fish is a common item in the daily diet of the Bangladesh populace. In this study, ten types of widely consumed dried fish (H. neherius, T. lepturu, P.chinensis, P. affinis, A. mola, P. microdon, I. megaloptera, C. dussumieri, L. calcarifer, and G. chapra) were analyzed for Cr, Mn, Fe, Co, Cu, Zn, Se, Rb, Hg, Pb, Ni and As by using an Energy Dispersive X-ray Fluorescence (EDXRF) technique. The concentration of the studied metals was found in the order Fe>Zn>Hg>Cu>Se>Cr>Mn>Co>Rb>Pb, while As and Ni were below the limit of detection. All fish species showed moderate to high pollution, where the species H. Neherius and P. Chinensis are the most and least polluted ones, respectively. The probable source of contamination is the leaching from the drying pans into the fish samples, atmospheric deposition, anthropogenic contamination, etc. of the water body where these fish were harvested. The calculated hazard index for the general population was below the maximum limiting value (i.e.,<1) except for Hg to children. The carcinogenic risk showed values lower than the acceptable limit for cancer risks (10(-6) to 10(-4)). Periodic monitoring of trace metals in the aquatic organisms along with fish is recommended to avoid any unexpected health hazards caused by the toxic heavy metals via fish consumption.

Automated summary

The study analyzed the metal content in ten types of dried fish consumed in Bangladesh, finding that these fish species are generally moderately to highly polluted, mainly due to contamination during the drying process, atmospheric deposition, and anthropogenic contamination. The study indicated that H. Neherius and P. Chinensis are the most and least polluted species, respectively. For the general population, the health hazards from consuming fish remain within acceptable limits.