A contaminated aquatic environment may end up in the food chain and pose risks to tourist health in a tourist destination. To assess the health risk for tourists that visit St. Martine Island, which ...is a popular domestic and foreign tourist destination in Bangladesh, a study is undertaken to analyse the level of heavy metal contamination from chromium (Cr), manganese (Mn), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), lead (Pb), mercury (Hg) and iron (Fe) in six of the most consumed fish (L. fasciatus, R. kanagurta, H. nigrescens, P. cuneatus, P. annularis and S. rubrum) and five crustacean species, which consist of a shrimp (P. sculptilis), a lobster (P. versicolor) and three crabs (P. sanguinolentus, T. crenata and M. victor) captured. The samples were analysed for trace metals using atomic absorption spectrometer, and the concentrations of the metals were interpreted using the United State Environmental Protection Agency (USEPA) health risk model. The muscle and carapace/exoskeleton of shrimp, lobster and crabs were analysed and contained various concentrations of Pb, Hg, As, Cr, Cd, Fe, Cu, Zn and Mn. The hierarchy of the heavy metal in marine fish is Fe > Cd > Zn > Pb > Cu > Cr > Mn > Hg. The concentrations of Pb in the species R. kanagurta, H. nigresceus and S. rubrum were above the food safety guideline by Australia, New Zealand and other legislations in most marine fish and crustaceans. Crabs showed higher mean heavy metal concentrations than shrimp and lobster. Acceptable carcinogen ranges were observed in three fish species (R. kanagurata, H. nigresceus and S. rubrum) and one crustacean species (P. sculptilis) samples.
This study aimed to assess the effects of major ecotoxic heavy metals accumulated in the Buriganga and Turag River systems on the liver, kidney, intestine, and muscle of common edible fish species
...Puntius ticto
,
Heteropneustes fossilis
, and
Channa punctatus
and determine the associated health risks. K was the predominant and reported as a major element. A large concentration of Zn was detected in diverse organs of the three edible fishes compared with other metals. Overall, trace metal analysis indicated that all organs (especially the liver and kidney) were under extreme threat because the maximum permissible limit set by different international health organizations was exceeded. The target hazard quotient and target cancer risk due to the trace metal content were the largest for
P. ticto
. Thus, excessive intake of
P. ticto
from the rivers Buriganga and Turag could result in chronic risks associated with long-term exposure to contaminants. Histopathological investigations revealed the first detectable indicators of infection and findings of long-term injury in cells, tissues, and organs. Histopathological changes in various tissue structures of fish functioned as key pointers of connection to pollutants, and definite infections and lesion types were established based on biotic pointers of toxic/carcinogenic effects. The analysis of histopathological alterations is a controlling integrative device used to assess pollutants in the environment.
The study aimed to determine eight hazardous heavy metals in surface water and sediment samples collected from the Naf River, Shah Porir Dwip (estuary), and mostly around Saint Martin’s Island in the ...Bay of Bengal. The results of heavy metals in water samples were ranged as Pb 14.7–313.0, Cd 33.0–70.0, Cr < 11.0–37.0, Cu 38.0–57.0, Zn 26.8–69.2, Ni 102.0–285.0, and Hg 0.3–1.6 μg L
−1
. The concentrations of metals in sediment samples were ranged as Pb < 10.0–37.5, Cd 0.2–1.0, Cr < 5.0–30.1, Cu < 3.0–30.9, Zn 24.1–88.0, Ni < 4.0–48.3, As 0.1–7.3, and Hg < 0.01–0.08 mg kg
−1
dw. Ni and Cr were strongly correlated, suggesting that this pair of metals might diffuse from a common origin. The contamination factor (
C
i
f
) demonstrated that sediment samples were mostly contaminated by Cd and slightly contaminated by Pb and Zn. The geoaccumulation index (
I
geo
) revealed considerable values for Cd on Saint Martin’s Island. Cd as a single regulator posed moderate to considerable risk frequently among the sampling stations. Pollution load index (PLI) values remained below 1 (< 1), which indicated a decrease from baseline pollution value among all stations. However, potential ecological risk (PER) was graded for two stations (St1 and St13) with a moderate-risk zone due to the Cd contribution. However, shipping emission and lithogenic sources were the most predominant for heavy metals in the sediment, which were determined by applying the principal component analysis-absolute principal component score (PCA-APCS).
Graphical abstract
