Bioaccumulation of heavy metals in some

Overview

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Key numbers

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Editor: Zhenguang Yan, Chinese Research chy of the measured concentration level (mg/kg) of the metals was as follows: Pb (13.88) >
chronic exposure to Cd, even at a low concentration of ~ 1 mg/kg (17, 18). Excessive Pb can
100% HNO3. The solution was heated on an oil bath and added with 4 drops of H2O2 repeat-
cance (confidence level in 95%). In addition, the Levene’s test with the significant level at
centration in the aquatic environment (mg/l). BAF is categorized as follows: BAF < 1000: no
for the consequence of exposure to the substantial carcinogens (72, 73). The acceptable range
Where CSf is oral slope factor of particular carcinogen (mg/kg-day) (74). Available CSf values
(mg/kg-day) are: As (1.5), Pb (0.0085) and Cd (6.3) (74).
The average concentration of Pb, Cu, As, Cr, and Cd from the fish tissues were 13.88 mg/kg
Cd (please see Table 1). From the results, Pb was 1.14, 2.8, 4.13, and 35.44 folds higher than
Cu, As, Cr, and Cd respectively, and contributed 40% of all the elements in the study area.
Along with that, Pb attributed a higher concentration of 15.73 mg/kg at S1, whereas Cd was
The evaluated MPIs ranged from 3.65 mg/kg to 4.70 mg/kg with the mean of 4.02 mg/kg
(Table 1). Due to higher concentration level, the maximum MPI value (4.70 mg/kg) was corre-
mg/kg), M. cephalus (3.69 mg/kg), and L. parsia (3.65 mg/kg).
species along the sampling stations. From Table 2, among the species, L. parsia and H. limbatus
for Pb (R2 = 99.5%), followed by L. parsia for As (R2 = 83.7%).
Table 3 depicts the correlation matrix among the metals in different fish species. The most
Table 1. Concentration of heavy metals of different species and their feeding nature, length and weight and a comparison of other relevant studies along with vari-
factors were responsible for cumulative variance of 96.93%. Cu and Pb were the most domi-
the contrary, in PC 2, Cd and Cu showed the domination with the loadings of 77.81% and
hence, it represented isometric growth pattern that was considered as ideal shape (Table 4).
The estimated BAFs are depicted in Fig 4. The BAFs were ranged from 110.53 for Cd
Table 2. A regression analysis between metal distributions in the selected specimens.
Species and metals Regression equation Standard error Pearson’s r P values R2 (%)
rized in Table 5. Adults and children showed comparably higher EDIs for demersal species
Table 3. Pearson’s correlation coefficient between heavy metal elements and matrix of PCA loadings.
The assessed target hazard quotient (THQ) for the studied fish species are displayed in Table 6.
Exposure of CR was estimated for a particular element and summarized in Table 6. The mea-
sured CR values of As, Pb and Cd were ranged from 5.14E-06- 1.35E-05, 8.48E-08- 1.79E-05
Table 5. A comparison between recommended daily allowance (RDA) and estimated daily intake (EDI) for adults and children.
Table 6. Calculated THQ, HI and CR for the selected two aged groups.
and 1.3–14 Cu mg/kg dry weight of muscles (86), which were generally lower than the present
The CR values lower than 10−6 indicates a negligible health risk whereas values in the range
of 10−6–10−4 are in the acceptable belt (63). The CR values found in this study suggested an
acceptable limit, and consumers are therefore less prone to carcinogenic risk. In fact, 90% of
state of As is more lethal than organic one (20, 115), and only 10% of the total As can be
assessed as inorganic form (63). The findings of the present study were in the acceptable range
1. USEPA. Region III Risk-Based Concentration Table: Technical background information. pp 227.
1. USEPA. Risk-based concentration table. United States Environmental Protection Agency, Washing-
1. USEPA. Region 9, Regional Screening Level (RSL) Summery Table (TR = 1E-6, HQ = 1.0). 2014.

Methods (brief)

Specimens from wild populations were collected from local fishermen. None of the sampled
Hyporhamphus limbatus (Ek Thuitta), and Tenualosa toil (Chandana ilish) were collected
The collected samples were carried in plastic ice container and immediately stored at –20˚C.
ther chemical analysis using inductively coupled plasma mass spectrometry (ICP-MS, Model:
A 1.5 g of dissected muscle was used for subsequent analysis. The samples were dried in a Zir-
Ø200×200 mm) for 24 h (30). After cooling, 0.5 g of muscle samples were placed in 10ml of of
the concentration of nth metal (mg/kg dry wt) in the tissue sample of a certain species.
and thus differentiated the contamination status of the samples (41–43).
The length-weight relationship of the fish samples were calculated using Fulton condition fac-
fish samples and the equation is as follows (3, 19, 66, 67):
lower than present results, except Cu. The concentrations of Cd and Cu in the fish collected
sampled tissues and finally, the surrounding environmental condition in which the species live
risk assessment of heavy metals in tropical fish and shellfish collected from the river Buriganga, Ban-
fishes collected from the waterway in Pearl River Delta in south China. Journal of Agro-Environment
1. Liu Q, Liao Y, Shou L. Concentration and potential health risk of heavy metals in seafoods collected
benzene in food samples of Iran’s market. Food and Chemical Toxicology. 2018; 114:278–284.
Trace metal contamination in commercial fish and crustaceans collected from coastal area of Bangla-

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Update history

The five most recent substantive edits to this page, classified major (evidence or structure moved), correction (a published value or statement was wrong and has been fixed), or minor (narrative rewritten without changing the underlying evidence). Each description is derived from what the edit did to this page; the linked commit is the authoritative record, routine regeneration passes are excluded, and the full version history lives in git. When DOI minting comes online (see schema docs), each entry below will also link to a version-pinned DataCite DOI.

Commit	Date	Change	Description
b01ec52c	2026-08-04	major	2 sections added
d49e450f	2026-08-03	major	5 sections added; narrative text revised