Tissue metal distribution and risk assessment for important fish species from Saudi Arabia

Melatonin as an Ameliorative Agent Against Cadmium- and Lead-Induced Toxicity in Fish: an Overview

Diverse anthropogenic activities and lack of knowledge on its consequences have promoted serious heavy metal contaminations in different aquatic systems throughout the globe. The non-biodegradable nature of most of these toxic heavy metals has increased the concern on their possible bioaccumulation in aquatic organisms as well as in other vertebrates. Among these aquatic species, fish are most sensitive to such contaminated water that not only decreases their chance of survivability in the nature but also increases the probability of biomagnifications of these heavy metals in higher order food chain. After entering the fish body, heavy metals induce detrimental changes in different vital organs by impairing multiple physiological and biochemical pathways that are essential for the species. Such alterations may include tissue damage, induction of oxidative stress, immune-suppression, endocrine disorders, uncontrolled cell proliferation, DNA damage, and even apoptosis. Although uncountable reports have explored the toxic effects of different heavy metals in diverse fish species, but surprisingly, only a few attempts have been made to ameliorate such toxic effects. Since, oxidative stress seems to be the underlying common factor in such heavy metal-induced toxicity, therefore, a potent and endogenous antioxidant with no side effect may be an appropriate therapeutic solution. Apart from summarizing the toxic effects of two important toxicants, i.e., cadmium and lead in fish, the novelty of the present treatise lies in its arguments in favor of using melatonin, an endogenous free radical scavenger and indirect antioxidant, in ameliorating the toxic effects of heavy metals in any fish species.

Hemato-biochemical alteration in the bronze featherback Notopterus notopterus (Pallas, 1769) as a biomonitoring tool to assess riverine pollution and ecology: a case study from the middle and lower stretch of river Ganga

Fishes are poikilothermic animals and are rapid responders to any sort of ecological alteration. The responses in the fish can be easily assessed from their hematological and biochemical responses. To study the variation in the hemato-biochemical parameters in retort to ecological alteration and ecological regime, a study was conducted at six different sampling stations of the middle and lower stretches of river Ganga. Various hematological and biochemical responses of fishes were also monitored in response to multiple ecological alterations. For the assessment of ecological alteration, various indices were calculated such as the water pollution index (WPI), National Sanitation Foundation-water quality index (NSF-WQI), and Nemerow's pollution index (NPI) has been calculated based on various water quality parameters such as dissolved oxygen (DO), pH, total dissolved solids (TDS), total alkalinity (TA), total hardness (TH), electrical conductivity (EC), biochemical oxygen demand (BOD), chlorinity (CL), total nitrogen (TN), and total phosphorus (TP). The hematological parameters such as WBC, RBC, platelet, hemoglobin, and hematocrit were monitored. The serum biochemical parameters such as SGPT, SGOT, ALP, amylase, bilirubin, glucose, triglyceride (TRIG), and cholesterol (CHOL) were investigated. The study revealed that NSF-WQI varied from 45.08 at Buxar to 110.63 at Rejinagar and showed a significantly positive correlation with SGPT, SGOT, ALP, TRIG, CHOL, and WBC, whereas a significantly negative correlation was observed between TRIG and RBC. WPI varied from 19 to 23 and showed a significant positive correlation with SGOT and a negative correlation was observed with total nitrogen. The PCA analysis illustrated the significance of both natural as well as anthropogenic factors on riverine ecology. Strong positive loading was observed with SGPT, SGOT, ALP, and platelet. The study signified the need for monitoring the hemato-biochemical responses of fishes in response to alterations in the ecological regime.

Response of vanadium bioaccumulation in tissues of Mugil cephalus (Linnaeus 1758)

Vanadium accumulation levels in different tissues (muscle and organs) of the striped mullet Mugil cephalus (Linnaeus, 1758) and possible relationships with blood parameters were evaluated in a Natural Protected Area (Lake Faro, Sicily, Italy), during the winter of 2017. Hematological parameters (red blood cell, RBC; white blood cell, WBC; hemoglobin concentration, Hb; hematocrit, Hct; mean corpuscular volume, MCV; mean corpuscular hemoglobin, MCH; mean corpuscular hemoglobin concentration, MCHC; thrombocytes, TC), biometric indices (weight, total and fork length), and vanadium levels in muscles and organs (gills, liver, stomach and intestine) were determined. Statistical analyses showed significant differences in concentrations of vanadium of the analyzed tissue of M. cephalus and a positive relationship between vanadium concentration in the liver and some hematological parameters (RBC, Hb and Hct) and biometric indices. Our results underline the importance of fish blood parameters as sensitive indicators of toxic impact of environmental factors such as metals. This study, focusing on an ongoing topic, represents a valuable contribution to research concerning the monitoring and prevention of vanadium pollution in aquatic organisms and environments.

Accumulation of Heavy Metals in Some Organs in Barbel and Chub from Crn Drim River in the Republic of Macedonia

Heavy metal pollution of aquatic ecosystems is worldwide problem with consequences on the aquatic organisms. The concentrations of selected heavy metals (Fe, Mn, Zn, Cu, Cd and Pb) were determined in liver, kidney, gills, muscle and bone of barbel (Barbus rebeli) and chub (Squalius squalius) from the river Crn Drim in Macedonia. In general, liver and kidney in both fish species contained the highest concentration of the investigated metals, while muscle showed lowest bioaccumulation of heavy metals. Analyses supported significant seasonal differences in some organs for some metals: highest value in spring-summer compared to autumn-winter period. Generally, metal concentration was higher in the barbel than chub. The concentration of metals in muscle are bellow permissible value and do not constitute any threat for human health due to the consumption of metal loaded fish.

Heavy Metal Content in Chilean Fish Related to Habitat Use, Tissue Type and River of Origin

In this study, we analyze the concentration of ten metals in two freshwater fish-the benthic catfish Trichomycterus areolatus and the limnetic silverside Basilichthys microlepidotus-in order to detect possible accumulation differences related to fish habitat (benthic or pelagic), tissue type (gill, liver and muscle), and the river of origin (four different rivers) in central Chile. The MANOVA performed with all variables and metals, revealed independent effects of fish, tissue and river. In the case of the fish factor, Cu, Cr, Mo and Zn showed statistically higher concentrations in catfish compared with silverside for all tissues and in all rivers (p < 0.05). In the case of the tissue factor, Al, Cr, Fe and Mn had statistically higher concentrations in liver and gills than in muscle (p  < 0.05). For the river effect, the analysis showed higher concentrations of Cr, Mn and Pb in the Cogoti river and the lower concentrations in the Recoleta river. These results suggest that not all metals have the same pattern of accumulation; however, some metals tend to accumulate more in readily catfish, probably due to their benthic habit, and in liver and gill tissue, probably as a result of accumulation from food sources and respiration.

Monitoring Water Pollution Levels in Wadi Hanifa, Riyadh, Saudi Arabia and its Public Health Implications

This study was performed to evaluate the levels of metals in the fish caught from Wadi Hanifa's main basin over four seasons, determine the potential fitness of the fish for human consumption, and evaluate the overall water quality after enforcement of local standards. The physical and chemical parameters from a total of 192 water samples were tested using standard methods. Additionally, a total of 48 fish samples were analyzed for heavy metal concentrations. Mean values for basic water quality parameters of COD, PO₄^-3, NH₃^--N, and NO₃^--N exceeded Saudi standards in all seasons. Mean metal concentrations in water were consistently at their highest concentrations in samples collected during the summer, and the lowest in samples collected during the winter. Mean metal concentrations in fish muscle tissue exceeded Saudi standards for As and Cd, and United Nations FAO standards for Cr, Ni, Zn, Fe and Mn. Statistical analysis showed highly significant positive correlations between metal concentrations in water and metal concentrations in fish muscle for As-Fe, Pb-Cr, Pb-Ni, Cr-Cu, and Cu-Fe. This study highlights the urgent need for monitoring and controlling wastewater discharge in Wadi Hanifa to ensure public safety.

Fish scales as a non-lethal tool of the toxicity of wastewater from the River Chenab

Water pollution is gradually increasing in natural waters through anthropogenic activities. This study aimed to use fish scales as a bio-indicator of pollution, along with water quality parameters, and the assessment and detection of selected heavy metals in water samples collected from the River Chenab, including the Chakbandi drain that gathers domestic sewage waste and industrial effluents from Faisalabad and deposits it into this freshwater body. All water quality parameters (pH, total dissolved solids (TDS), total suspended solids (TSS), salinity, conductivity, biochemical oxygen demand (BOD), chemical oxygen demand (COD), phenols and sulphates) and concentrations of selected heavy metals (Cd, Cu, Mn, Pb and Cr) were found to be considerably higher than permissible limits as defined by the WHO, and therefore capable of causing ill health effects in aquatic organisms. Specimens of fish scales from selected fish were described qualitatively and observed quantitatively. In Catla catla, Labeo rohita and Cirrhinus mrigala, the scales showed several deformities in shape and different scale structures such as circuli, radii and annuli. In each of the three types of fish, considerable variation in the morphology of their scales was observed in specimens collected from polluted sites.

Accumulation behavior and risk assessment of heavy metals and arsenic in tissues of white bream (Parabramis pekinensis) from the Xiang River, southern China

Aquatic environment suffered from serious heavy metal and As pollutions due to rapid industrialization and urbanization in the last decades. In order to evaluate the heavy metal and As contamination in aquatic organism in southern China, the levels of As, Cd, Co, Cr, Cu, Fe, Mn, Pb, and Zn in muscle, gill, and liver of white bream (Parabramis pekinensis) collected from Xiang River were analyzed. The statistically significant differences of the analyzed element concentration (wet weight) between tissues were determined through one-way analysis of variance (ANOVA). The liver presented high affinity for accumulation of Cd, Cu, and Zn due to the binding activity of metallothionein proteins. Mn and Pb mainly accumulated in the gill indicated the major uptake route through the gill. Lack of correlation between analyzed element and fish size might imply no or weak biomagnification of the analyzed elements in fish tissues. The potential health risk associated with exposure to heavy metals and As was evaluated. The uncertainty of target hazard quotient was calculated by Monte Carlo simulation. The results indicated that the analyzed element contents in the white bream muscle posed relatively low-chronic toxic risk to consumers.

Surface water quality in a water run-off canal system: A case study in Jubail Industrial City, Kingdom of Saudi Arabia

Water quality in a run-off canal system in an industrial area was evaluated for a range of physical and chemical properties comprising trace metals (including mercury (Hg), chromium (Cr), iron (Fe), manganese (Mn), salinity, pH, turbidity, total dissolved solids, total suspended solids, chemical oxygen demand (COD), and dissolved oxygen). High concentrations of potassium (K) (1.260–2.345 mg/l) and calcium (Ca) (19.170–35510 mg/l) demonstrated that the salinity in the water was high, which indicates that industrial effluents from fertilizer manufacturing and Chlor-alkali units are being discharged into the canal system. Almost all the metal concentrations in water and sediment were within the thresholds established by the local regulatory body. Concentrations of Cr (0.0154–0.0184 mg/l), Mn (0.0608–0.199 mg/l), Fe (0.023–0.035 mg/l), COD (807–916 mg/l), and turbidity (633 ± 15–783 ± 22 NTU) were high where the canal discharges into the Persian Gulf; these discharges may compromise the health of the aquatic ecosystem. There is concern about the levels of Hg in water (0.00135–0.0084 mg/l), suspended sediment (0.00308–0.0096 mg/l), and bed sediment (0.00172–0.00442 mg/l) because of the bio-accumulative nature of Hg. We also compared the total Hg concentrations in fish from Jubail, and two nearby cities. Hg contents were highest in fish tissues from Jubail. This is the first time that heavy metal pollution has been assessed in this water run-off canal system; information about Hg is of particular interest and will form the basis of an Hg database for the area that will be useful for future investigations.

Combining multivariate analysis and human risk indices for assessing heavy metal contents in muscle tissues of commercially fish from Southern Red Sea, Saudi Arabia

Jizan fishers are the major fish source for more than 1.5 million populations in the southern region in Saudi Arabia. Despite the overgrowing of various man-made activities in Jizan City, no recent study on environmental monitoring was reported. In the current study, heavy metals were quantified in muscle tissues of 12 fish species, as the most edible, from Jizan fisheries. Electrothermal atomic absorption spectrophotometry was used for quantification after microwave wet digestion. Acceptable recovery values (83.46-97.48%) for spiked fish samples with standard solutions were obtained. The following wide ranges of heavy metal concentrations (μg/g, wet weight) in studied fish species were recorded: V (0.004-0.561), Cr (0.013-0.477), Mn (0.073-0.128), As (0.002-0.935), Se (0.083-3.058), Sn (2.835-5.540), and Pb (0.150-0.386). Comparing with international permissible limits, lower levels were recorded in the current study. For total metal accumulation, the relationship between species was examined by cluster analysis, which showed that Epinephelinae was the farthest species from others. The principal component analysis shows one component indicating normal distribution of heavy metals in fish species. Different metal pollution indices (1.35-0.30), which shows the distribution of the total heavy metal concentrations in each species, were recorded. The hazard indices for muscle consumption were less than 1.0 for all studied metals at both ingestion rates except Sn which showed a marginal value of 28.9.

Trace Elements in Water, Sediments and the Elongate Tigerfish Hydrocynus forskahlii (Cuvier 1819) from Lake Turkana, Kenya Including a Comprehensive Health Risk Analysis

This study presents the distribution of 17 major and trace elements in surface water, sediments and fish tissues from Lake Turkana, Kenya. Eight sediment and ten water samples from the west bank of the lake, as well as 34 specimens of the elongate tigerfish Hydrocynus forskahlii caught in that region were examined. It is the first report for Li, Rb, Sr, Mo from the lake and the first report on most of the trace elements for this fish species. The concentrations of elements in the water and sediments showed no sign of pollution. In fish muscle, Li, Zn and Cd showed relatively high abundances, with mean concentrations of 206, 427 and 0.56 mg/kg dw, respectively. The calculated target hazard quotient values for Li, Zn, Sr and Cd were 138.7, 1.9, 4.1 and 0.76, respectively; therefore the consumption of these fish poses a health risk to humans in the area.

Seasonal variations in the body composition and bioaccumulation of heavy metals in Nile tilapia collected from drainage canals in Al-Ahsa, Saudi Arabia

The body composition of Nile tilapia (Oreochromis niloticus) collected from drainage canals in Al-Ahsa, Saudi Arabia and the concentration of four heavy metals; zinc (Zn), cadmium (Cd), cobalt (Co) and lead (Pb) in both fish muscles and the water collected from this environment were assessed across the four seasons. The body composition was found to change with the seasons, with the best body composition being recorded in autumn and winter, where higher levels of protein (17.24, 17.65%), and fat (0.58, 0.71%) and lower water content (80.15, 79.86%) respectively were noted. The concentration of heavy metals in both fish muscles and the water body also varied significantly with the seasons. In the fish muscles, the highest content of Zn (0.409 mg/kg dry weight) and Cd (4.140 mg/kg dry weight) was recorded in winter, however, the highest concentration of Co (0.318 mg/kg dry weight) and Pb (1.96 mg/kg dry weight) was observed in spring and summer respectively. On the other hand, the water samples collected in autumn showed the maximum concentration of Cd (1.385 mg/L), Co (0.762 mg/L) and Pb (0.18 mg/L) however, the maximum concentration of Zn (0.0041 mg/L) was recorded in winter. With the exception of Cd, the accumulation of the studied heavy metals in fish muscles was within the safe limits for seafood recommended by various organizations.

Assessment of metal contamination in water, sediment, and tissues of Arius thalassinus fish from the Red Sea coast of Yemen and the potential human risk assessment

Heavy metal pollution is one of the most serious environmental issues globally. To evaluate the metal pollution in the Red Sea coast of Hodeida, Yemen Republic, the concentrations of Fe, Cu, Ni, Pb, and Cd in water, sediment, and some vital organs of sea catfish, Arius thalassinus collected from polluted and unpolluted sites, were determined. The risk of these metals to humans through fish consumption was then assessed. The results showed that the concentration order of metals in water, sediment, and fish tissues were Fe > Cu > Ni > Pb > Cd. The levels of studied metals in water, sediment, and fish tissues were significantly higher in the polluted site than those of the unpolluted site, with few exceptions. Linear correlation incorporating paired variables (water-sediment, water-fish, and fish-fish) exhibited several significant correlations indicating a common metal pollution. The risk assessment performed revealed that fish consumption was safe for consumers. This field investigation provides a baseline data on metal pollution in this region.

Monitoring of trace metals in tissues of Wallago attu (lanchi) from the Indus River as an indicator of environmental pollution

We aimed to assess the bioaccumulation of selected four trace metals (Cd, Ni, Zn and Co) in four tissues (muscles, skin, gills and liver) of a freshwater fish Wallago attu (lanchi) from three different sites (upstream, middle stream and downstream) of the Indus River in Mianwali district of Pakistan. Heavy metal contents in water samples and from different selected tissues of fish were examined by using flame atomic absorption spectrometry. The data were statistically compared to study the effects of the site and fish organs and their interaction on the bioaccumulation pattern of these metals at P < 0.05. In W. attu the level of cadmium ranged from 0.004 to 0.24; nickel 0.003–0.708; cobalt 0.002–0.768 and zinc 47.4–1147.5 μg/g wet weight. The magnitude of metal bioaccumulation in different organs of fish species had the following order gills > liver > skin > muscle. The order of bioaccumulation of these metals was Ni < Zn < Co < Cd. Heavy metal concentrations were increased during the dry season as compared to the wet season. The results of this study indicate that freshwater fish produced and marketed in Mianwali have concentrations below the standards of FEPA/WHO for these toxic metals.

A risk assessment of heavy metal concentrations in fish and an invertebrate from the Gulf of Antalya

This study was conducted to determine the levels of Cd, Cu, Zn and Pb in the Red mullet (Mullus barbatus), Grey mullet (Mugil cephalus) and Green tiger prawn (Panaeus semisulcatus) species caught in the Gulf of Antalya and to assess the health risks associated with their consumption. The average values (mg/kg d.w.) were calculated to be Pb (0.29 ± 0.14), Cd (0.02 ± 0.03), Zn (5.64 ± 1.58) and Cu (1.64 ± 1.02) in M. barbatus; Pb (0.22 ± 0.12), Cd (0.02 ± 0.01), Zn (7.66 ± 2.29) and Cu (1.33 ± 0.82) in M. cephalus; Pb (0.25 ± 0.16), Cd (0.04 ± 0.05), Zn (13.33 ± 3.34) and Cu (5.15 ± 2.09) in P. semisulcatus. The detected levels of the studied metals were below the legal and daily intake limits according to national and international standards, although the mean Pb level in M. barbatus was close to the legal limit (0.30 mg/kg). Target hazard quotient values were also all below 1, meaning that there is no health risk.