TITLE:
Status of Heavy Metals in Naturally Grown Native Fish in Bangladesh and Its Consequences on Human Health: A Comprehensive Review
AUTHORS:
Rupa Akter, Md Ataur Rahman, Rabia Akter Bijly, Mst Sanjida Akhter, Most Chand Sultana Khatun, Nowrin Ferdiousi, Gulam Khandaker, Md Rafiquzzaman
KEYWORDS:
Heavy Metals, Bioaccumulation, Naturally Grown Fish, Toxicity, Seasonal Impact, Bangladesh
JOURNAL NAME:
American Journal of Analytical Chemistry,
Vol.16 No.5,
May
30,
2025
ABSTRACT: Background: Heavy metals are well-known environmental contaminants due to their harmful effects, persistence in the natural environment, and tendency to bioaccumulate. Hazardous heavy metal pollution in terrestrial and aquatic ecosystems poses a serious threat to the environment and human health due to food chain contamination and bioaccumulation. Objective: This study aimed to provide a comprehensive review of the accumulation of heavy metals, such as lead (Pb), chromium (Cr), arsenic (As), and others, in various species of naturally grown native fish in Bangladesh. Methods: For this study, various electronic databases were carefully searched using appropriate keywords for papers on the concentrations of toxic heavy metals accumulation in naturally grown native fish in Bangladesh from January 2010 to January 2020. Results: The literature review revealed the presence of lead (Pb), chromium (Cr), arsenic (As), zinc (Zn), cadmium (Cd), copper (Cu), iron (Fe), and manganese (Mn) in 33 varieties of naturally grown native fish in Bangladesh. Heavy metals were detected in over 90% of the reported fish samples. Among all the reported fish and heavy metals, the Shingi fish contained the highest concentration of heavy metals, specifically Pb at 63.63 mg/kg, while the highest concentration of Mn was found in Bacha fish at 1.69 mg/kg. In contrast, the Puti and Tank goby (or Bele) fish had the lowest concentration of Cd among all the cited fish varieties, with only 0.002 mg/kg. The highest concentrations (mg/kg) of specific heavy metals among all the observed fish, regardless of fish type, followed this order: Pb (63.63) > Cu (26.60) > Zn (14.37) > Cr (6.42) > Cd (6.22) > As (5.26) > Fe (3.02) > Mn (1.69). Owing to the high variability of heavy metal content in fish, the comparison is made based on median values (mg/kg), which followed the decreasing order: Cu (5.31) > Fe (2.20) > As (0.99) > Zn (0.91) > Pb (0.67) > Cr (0.65) > Mn (0.26) > Cd (0.11). The percentages (%) of fish samples that exceeded the safety limit of specific heavy metal content followed this order: 63.04 (Pb) > 52.17 (Cu) > 37.50 (Cd) > 25.00 (Mn) > 9.68 (As) > 0% (Cr = Fe = Zn). Conclusion: Eight heavy metals were reported in 33 varieties of naturally grown native fish in Bangladesh. The concentrations of Pb, Cd, As, Mn and Cu exceeded the safe limits in varieties of naturally grown native fish in Bangladesh and Pb, Cd and Cu in almost all of the fish from the Karnaphuli River and the sea exceeded the recommended values for safe consumption among other sources. During the winter, the concentration of heavy metals in all types of fish was higher than in the summer. The incorporation of heavy metals into aquatic food chains leads to human exposure pathways and is associated with various pathological conditions and health hazards.