Metallic Contamination of the Muscles of Three Fish Species from the Moulouya River (Lower Moulouya, Eastern Morocco)

This study introduces a spatiotemporal evaluation of the metallic contamination with three trace metals (mercury, lead, and cadmium) in the muscles of three fish species (Lepomis macrochirus, Barbus callensis, and Barbus nasus), of which the samples were taken from three stations in the Moulouya River: the confluence of the Moulouya River and the Sebra River (station 1), the neighbourhood of the farms in the region of Aklim downstream from confluence of Lakhmis river (station 2), and the level of ancient bridge of Ras El Ma-Moulouya (station 3), during the period from July 2017 to May 2018. The results have allowed us to highlight rather high contents of lead and mercury in the fish muscles, mainly in station 1, which receives domestic and industrial discharges. The contents of cadmium in all fish species in different stations are very low. Moreover, all concentrations assessed in different fish species do not exceed the maximum limit recommended by European Community (EC) Commission Regulation No. 1881/2006.

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Mercury, Lead, and Cadmium in the Muscles of Five Fish Species from the Mechraâ-Hammadi Dam in Morocco and Health Risks for Their Consumers

Journal of Toxicology ◽

10.1155/2021/8865869 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

Mohammed Mahjoub ◽

Soufiane Fadlaoui ◽

Mohammed El Maadoudi ◽

Youssef Smiri

Keyword(s):

Trace Metals ◽

Atomic Absorption Spectrometry ◽

Atomic Absorption ◽

Health Risks ◽

Fish Species ◽

Graphite Furnace ◽

Micropterus Salmoides ◽

Lepomis Macrochirus ◽

Absorption Spectrometry ◽

Lead And Cadmium

This study aims to assess the degree of metal contamination (mercury (Hg), cadmium (Cd), and lead (Pb)) in the muscles of five species of fish Esox lucius, Sander lucioperca, Micropterus salmoides, Lepomis macrochirus, and Scardinius erythrophthalmus, from the Mechraâ-Hammadi Dam between July 2017 and May 2018, and to conduct a risk assessment for human consumers. Trace metals were determined by Graphite Furnace Atomic Absorption Spectrometry for the Pb and the Cd and by Cold Vapor Atomic Absorption Spectrometry for the Hg. The results gotten from the study of the muscles of the different fish species show that the higher mean amounts of Cd and Hg were determined in E. lucius, and the maximum mean levels of Pb were detected in S. erythrophthalmus. Results suggested that demersal fishes inhabiting near the sediments and piscivorous fishes with higher trophic level were likely to accumulate higher trace metal concentrations. The general order of bioaccumulation of the trace metals measured in the muscles of the fish species is as follows: Hg > Pb > Cd. Therefore, the bioaccumulation of Hg in fish studied is more important than that of Cd and Pb. Furthermore, these concentrations are higher in summer than in winter for all trace metals. All the values of the trace metals in the muscle tissues are below the maximum limits recommended by the European Community (EC) N° 1881/2006. However, estimation of noncarcinogenic health risks by the target hazard quotient indicated no obvious noncarcinogenic risks to humans that consume those fishes (THQ < 1). Results of THQ and maximum safe consumption indicated that Hg may cause more harm to human by fish consumption especially for E. lucius and S. lucioperca. Therefore, reduced intake of carnivorous fishes should be promoted as part of a healthier diet.

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Heavy Metal Concentrations in Fish from River Tano in Ghana and the Health Risks Posed to Consumers

Journal of Environmental and Public Health ◽

10.1155/2021/5834720 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

A. J. Nyantakyi ◽

S. Wiafe ◽

O. Akoto ◽

Bernard Fei-Baffoe

Keyword(s):

Trace Metals ◽

Health Risks ◽

Fish Species ◽

Clarias Gariepinus ◽

Good Condition ◽

Common Source ◽

Metal Concentrations ◽

Fish Muscles ◽

Fish Samples ◽

Mormyrus Rume

Appreciable levels of trace metals have been reported in the Tano basin, but data on the corresponding levels in fish and the risk they pose to consumers are limited. The levels of 7 trace metals in 18 fish muscles were assessed between November 2016 and October 2017 using acid digestion and PerkinElmer (PinAACle 900T) Atomic Absorption Spectrophotometry. Apart from Cu, all the metals studied were detected in all fish samples. The levels of Cr, As, and Hg were higher than the acceptable levels of fish muscles. Cr concentration ranged from 16.10 ± 0.2 mg/kg in Clarias gariepinus to 57.9 ± 4.2 mg/kg in Sarotherodon galilaeus. The levels of As ranged from 1.01 ± 0.08 in Clarias gariepinus to 3.00 ± 0.01 mg/kg in Mormyrus rume. Hg level was 0.58 ± 0.69 mg/kg in Oreochromis niloticus and 2.52 ± 0.70 mg/kg in Ctenopoma kingsleyae. However, Pb, Zn, and Cd concentrations were below the Food and Agriculture Organization limits with low target hazard quotients in all fish samples, suggesting no possible noncarcinogenic risks to adult consumers. Possible noncarcinogenic and carcinogenic health risks were recorded for As, Hg, and Cr in all fish species. Strong associations were observed between Hg, As, Zn, and Cr and between Pb and Cd suggesting a possible common source. Mormyrus rume fish species was under stress in the river, but the remaining species were in good condition. Periodic monitoring of trace metal concentrations in fish and enforcement of the buffer zone policy are recommended.

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Content of Toxic Heavy Metals (Mercury, Lead, and Cadmium) in Canned Variegated Scallops (Chlamys varia)

Journal of Food Protection ◽

10.4315/0362-028x-70.12.2911 ◽

2007 ◽

Vol 70 (12) ◽

pp. 2911-2915 ◽

Cited By ~ 11

Author(s):

A. J. GUTIÉRREZ ◽

D. GONZÁLEZ-WELLER ◽

T. GONZÁLEZ ◽

A. BURGOS ◽

G. LOZANO ◽

...

Keyword(s):

Heavy Metals ◽

Canary Islands ◽

Human Consumption ◽

Santa Cruz ◽

Toxic Heavy Metals ◽

Lead And Cadmium ◽

Shopping Area ◽

Commission Regulation ◽

Wet Weight ◽

Maximum Limit

The concentrations of three toxic heavy metals, mercury (Hg), lead (Pb), and cadmium (Cd), were determined in preserved variegated scallops (Chlamys varia, Bivalvia, Mollusca), which are often consumed in Tenerife (Canary Islands, Spain). A total of 300 samples of seven commercial brands (A, B, D, H, J, L, and M) and one processed product (“scallop sauce”) were analyzed. Samples were collected weekly in a major shopping area in Santa Cruz de Tenerife during a 12-month period. The concentrations of lead and mercury were far below the maximum limit permitted for human consumption by the European Communities Commission regulation (EC) 466/2001 (1 and 0.5 mg kg−1 wet weight for Pb and Hg, respectively). Concentrations of cadmium were close to the maximum limit permitted by regulation (EC) 466/2001 (1 mg kg−1 wet weight).

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Effect of the Human Utilization of Northern Snakehead (Channa argus Cantor, 1842) on the Settlement of Exotic Fish and Cladoceran Community Structure

Sustainability ◽

10.3390/su13052486 ◽

2021 ◽

Vol 13 (5) ◽

pp. 2486

Author(s):

Jong-Yun Choi ◽

Seong-Ki Kim

Keyword(s):

Community Structure ◽

Fish Species ◽

Micropterus Salmoides ◽

Lepomis Macrochirus ◽

Nakdong River ◽

Exotic Fish ◽

Carnivorous Fish ◽

Channa Argus ◽

The Nakdong River ◽

Exotic Fish Species

Empirical studies suggest that changes in the density of top predators, such as carnivorous fish, in freshwater food webs, strongly affect not only fish communities but also various primary and secondary consumers. Based on these findings, we explored how differences in the utilization of carnivorous fish (i.e., Northern Snakehead, Channa argus) by humans affected the fish and cladoceran community structure as well as the settlement of exotic fish species (i.e., Lepomis macrochirus and Micropterus salmoides) in 30 wetlands located in the upper and lower reaches of the Nakdong River. Our results show that in the mid–lower reaches of the Nakdong River, the density of C. argus was low, while high densities of L. macrochirus and M. salmoides were observed. Exotic fish species are frequently consumed by C. argus, leading to a low density of L. macrochirus and M. salmoides in the upper reaches, which supported a high density of C. argus. However, in the mid–lower reaches, the density of L. macrochirus was high because of the frequent collection of C. argus by fishing activities. The dominance of L. macrochirus significantly changed the structure of cladoceran communities. L. macrochirus mainly feeds on pelagic species, increasing the density of epiphytic species in the mid–lower reaches. The continued utilization of C. argus by humans induced a stable settlement of exotic fish species and strongly affected the community structures of primary consumers in the 30 wetlands. The frequency of C. argus collection has to be reduced to secure biodiversity in the mid–lower reaches of the Nakdong River, which will reduce the proportion of exotic fish species and increase the conservation of native fish.

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Quantitative comparisons of the morphology and ultrastructure of erythrocyte nuclei from seven freshwater fish species

Canadian Journal of Zoology ◽

10.1139/z95-229 ◽

1995 ◽

Vol 73 (10) ◽

pp. 1951-1959 ◽

Cited By ~ 4

Author(s):

Charles H. Jagoe ◽

Dave A. Welter

Keyword(s):

Fish Species ◽

Yellow Perch ◽

Micropterus Salmoides ◽

Lepomis Macrochirus ◽

Nuclear Size ◽

Image Analysis System ◽

Cell Nuclei ◽

Homogeneous Population ◽

Differentiated Cells ◽

Rainbow Trout Oncorhynchus Mykiss

Chromosome number and genomic DNA content vary widely among fish species, and ploidy can vary within species. This suggests that the size, shape, and morphological features of cell nuclei may also vary. Nucleated erythrocytes of fish are an easily sampled homogeneous population of differentiated cells ideal for inter- and intra-species comparisons. We collected blood samples from largemouth bass (Micropterus salmoides), bluegill (Lepomis macrochirus), chain pickerel (Esox niger), yellow perch (Perca flavescens), mosquitofish (Gambusia holbrooki), redeye bass (Micropterus coosae), and rainbow trout (Oncorhynchus mykiss) and removed cytoplasm and nuclear membranes from blood cells. Individual nuclei were examined and measured using scanning electron microscopy and a computerized image analysis system, and inter- and intra-species differences evaluated by nested analysis of variance. Nuclear size and shape varied significantly among species. Isolated nuclei had conspicuous apertures or holes, and the number and size of these holes also varied significantly among species. Variations in nuclear size and structure within species were small compared with interspecies differences. Little is known of the ultrastructure of erythrocyte nuclei in lower vertebrates, but their structure differs considerably from that of other vertebrate non-erythroid cells, suggesting that the organization of their DNA and associated proteins may be different.

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