Bioaccumulation and potential sources of heavy metal contamination in fish species in River Ganga basin: Possible human health risks evaluation

Ecological and Health Risk Assessment of Heavy Metals Bioaccumulation in Ganges Fish Near Varanasi, India

Heavy metal contamination in river Ganga is one of the factors for deterioration in its water quality and also adds to human health risks. We designed our study to achieve a holistic approach by not only estimating the concentration of heavy metals (lead, manganese, chromium, and cadmium) in the river water at different sites based on human anthropogenic activities but also in the fishes residing in the same sites that are collected for human consumption on daily basis. We found that Ganga River in Varanasi is highly loaded with metals (PLI = 6.698). Mean concentration in water was 1.29 mg/L for Pb, 1.325 mg/L for Mn, 0.169 mg/L for Cr, and 0.161 mg/L for Cd, which were above the permissible limits stated by Environment Protection Agency (EPA) in drinking water. Fish, including exotic and invasive species, were collected from the wild and were processed for the presence of these metals in their tissues. Degree of heavy metal concentration followed liver > gills > muscles. The highest accumulation of Pb was observed in Carpio (Cyprinus carpio) liver (8.86 µg/g) and lowest in Baikari (Clupisoma garua) muscles (0.07 µg/g). Total target hazard quotient (THQ) value, i.e., hazard index (HI) showed values in following sequence: Cyprinus carpio > Oreochromis niloticus > Channa gachua > Johnius coitor > Mastacembelus armatus > Mystus tengara > Clupisoma garua. Maximum HI value was recorded in C. carpio, which is highly consumed fish by humans, hence, may be harmful to them.

Heavy Metals Assessment and Health Risk to Consumers of Two Commercial Fish Species from Polyculture Fishponds in El-Sharkia and Kafr El-Sheikh, Egypt: Physiological and Biochemical Study

Metal pollution is a major environmental concern worldwide, especially in Egypt. The aquaculture industry uses widespread artificial feeds to stimulate fish production, leading to metal accumulation in the aquatic environment. Heavy metal concentrations (HMCs) in sediments, water, and tissues were studied to study the effect of pollution levels on heamatological, and biochemical, immunological aspects of farmed fish as well as on human health. Results declared that the HMC levels in the water and sediment were significantly different between El-Sharkia and Kafr El-Sheikh fishponds (T-test, p < 0.05). This was supported by the metal pollution index in the water and sediment, indicating that El-Sharkia fishponds (ES fishponds) were more contaminated than Kafr El-Sheikh fishponds (KES fishponds). Also, HMCs in fish tissues were significantly increased in fish cultivated in ES fishponds than in KES fishponds. Haematological, immunological, and biochemical alterations of Bolti (Oreochromis niloticus) and Topara (Chelon ramada) fish were significantly different within the different fish species as well as the different fishponds. From the human health perspective, the THQ-HMC and HI-HMC associated with the consumption of muscle suggest a safe non-carcinogenic risk to human health. In contrast, cadmium poses a cancer risk to children who consume the muscular tissue of Bolti fish from ES fishponds, which should be regarded as a warning sign based on data indices and a human health perspective. In order to minimise HMC pollution in the aquaculture sector, it is advisable to take possible assessments and carry out continuous monitoring considering international WHO/FAO assessments.

Assessment of persistent and emerging pollutants levels in marine bivalves in the Gulf of Suez, Egypt

Bivalves possess important ecological and economic values. They have been extensively used as bioindicators for both emerging and classical pollutants in the aquatic environment. This study investigates the levels of trace metals, polycyclic aromatic hydrocarbons (PAHs), and organochlorine pesticides (OCPs), alongside microplastic (MPs), in Tridacna maxima, Paphia textile, and Paratapes undulatus, collected from the Gulf of Suez. This work represents the first investigation of MPs in marine bivalves from the Gulf of Suez. MPs were detected in 72% of the specimens examined and four types of MPs were identified. The metal pollution index indicated that bivalves may have long-term toxic effects on human consumers. The results showed minimal hydrocarbon pollution. Diagnostic ratios indicated a combination of pyrolytic and petrogenic sources, with a notable influence from pyrolytic origins. The risk assessment reflected that the levels of certain trace metals, PAHs, and OCP contaminants could present a low risk to human health.

Heavy Metal Accumulation in Fish, Sediment and Water from Three Riverine Ecosystems in the South-western Bangladesh and Nexus to Human Health

This study investigated heavy metal accumulations in fish, water and sediment from three rivers around a major urban area in Bangladesh, namely the Rupsha, the Atai, and the Bhairab with a view to assessing the ecological and human health risks. Samples were collected from 10 stations over two seasons (summer and winter) and concentrations of 11 metals (As, Se, Pb, Be, Cd, Co, Cr, Cu, Mn, Ni, V) were measured using ICP-MS. Heavy metals in water of these rivers were above the WHO higher thresholds. The Rupsha River, which runs close to industrially dense areas and the downstream part of the three-river network, demonstrated the highest As, Cu, and V concentrations during both seasons. On the other hand, As, Mn and Cr were highest in the Bhairab which is the upstream to the Rupsha and connected to several industrial setups which differ from Bhairab. The less anthropogenically connected Atai River only showed elevated concentrations of Cu and Se. Ecological risk indices indicated low pollution in the rivers during both seasons. In all three rivers and in nearly all fish species, the contamination was higher in winter than summer. Benthic and carnivorous fish species such as, Cynoglossus lingua, Glossogobius giuris, Pseudapocryptes elongatus showed higher metal accumulation compared to other species. Health risk indices like the target hazard quotient (THQ) and carcinogenic risk (CR) suggested low risks but pointed potential risks to human health. The outcomes of this research reports insights into metal contamination pattern in interconnected river systems.

Toxic Metal Element Concentration in 31 Food Fishes from River Ganga: Risk Assessment on Human Consumption

Consumption of toxic metal contaminated fish is a significant risk to human health. The Ganga river is one of the vital river systems in India, and it nurtures a rich biodiversity of flora and fauna. In the present study, screening of potential toxic metal elements (Cd, Cr, Mn, Cu, Pb, Ni, Zn, and As) was undertaken in 31 food fishes, especially the small indigenous fishes (SIFs) from the lower stretch of river Ganga by inductively coupled plasma mass spectrometry (ICP-MS). The concentration of toxic metal elements varied among different fish species. Among the toxic metal elements studied, Cr, Zn, and As were found to be dominant in Eleotris fusca; Cd, Ni, and Pb were highest in Securicula gora; Cu was highest in Cabdio morar; and Mn was highest in Coilia dussumieri. The average pollution load index values (APLI) for all the fishes analyzed were less than one except for Eleotris fusca, which indicated no serious toxic metal element pollution load. The estimated daily intake values (EDI) for the toxic metal elements were found to be within the permissible maximum tolerable daily intake (MTDI). Among the fishes studied, only a few species showed hazard index (HI) greater than one, indicating non-carcinogenic health risks. Similarly, the target carcinogenic values (TCR) for most of the toxic metal elements were below the permissible limit (10-4) in the fishes that assures minimal cancer risk. This study provides a comprehensive data on the composition of potential toxic metal elements of 31 food fishes from the lower stretch of the river Ganga, the first of its kind, and suggests the necessity of periodic monitoring of these in the aquatic ecosystem.

Comprehensive assessment of groundwater quality in the Prayagraj District, Ganga Basin

Urbanization has severely impacted the world water resources especially the shallow groundwater systems. There is a need of a robust method for quantifying the water quality degradation, which is still a challenge for most of the urban centers across the world. In this study, a highly urbanized region of Ganga basin is selected to critically evaluate commonly used WQIs and compare with fuzzy modeling. A total of 28 water samples were collected from diverse sources (surface and groundwaters) in the vicinity of urban region covering an area of 216 km2 during the premonsoon period. TDS, TH, NO3-, and F- values were found to be above the permissible limits in 57%, 89%, 4%, and 7% samples, respectively. The WQIs (entropy and integrated) outputs were found to be similar with 89% of the samples falling under moderate category. Fuzzy modeling was carried out allowing user-defined weighting factors for the most influential ions, and the output suggested 96% of the samples falling under moderate to excellent categories. Based on the chemical results and considering the lithology of the study area, the geochemical reactions controlling the water quality were deduced. This study outlines a systematic approach of evaluating the overall water quality of an urban region highlighting the merits and limitations of WQIs. It also justifies the immediate need to generate more robust data to achieve the sustainable development goals 6 (clean water and sanitation) and 11 (sustainability of cities and human settlement).

Heavy Metal Concentrations in Water, Sediment, and Fish Species in Chashma Barrage, Indus River: A Comprehensive Health Risk Assessment

The increasing levels of heavy metals in aquatic environments, driven by human activities, pose a critical threat to ecosystems' overall health and sustainability. This study investigates the bioaccumulation of heavy metals (Pb, Cu, Cr, and Cd) in water, sediment, and three fish species (Catla catla, Labeo rohita, Cirrhinus mrigala) of different feeding zones within Chashma Barrage, located in the Mianwali district of Punjab, Pakistan, on the Indus River. A comprehensive analysis, including an assessment of associated human health risks, was conducted. Thirty samples from all three sites for each fish species, with an average body weight of 160 ± 32 g, were collected from Chashma Barrage. Water quality parameters indicated suitability for fish growth and health. Heavy metal concentrations were determined using an atomic absorption spectrometer. Results indicated elevated levels of Cd, Cr, and Cu in sediment and Pb and Cd in water, surpassing WHO standard limits. Among the fish species, bottom feeder (C. mrigala) exhibited significantly (P < 0.05) higher heavy metal levels in its tissues (gills, liver, and muscle) compared to column feeder (L. rohita) and surface feeder (C. catla). Liver tissues across all species showed higher heavy metal bioaccumulation, followed by gills. Principal component analysis (PCA) revealed strong correlations among heavy metals in sediment, gills, muscle, and water in every fish species. However, the vector direction suggests that Cr was not correlated with other heavy metals in the system, indicating a different source. The human health risk analysis revealed lower EDI, THQ, and HI values (< 1) for the fish species, indicating no adverse health effects for the exposed population. The study emphasizes the bioaccumulation differences among fish species, underscoring the higher heavy metal concentrations in bottom feeder fish within Chashma Barrage.

Essential and Non-Essential Elements Levels in Fish Species Highly Consumed in the Middle Miranda River, Brazilian Pantanal

The present study investigated the levels of As, Ag, Al, Ba, Cd, Cr, Cu, Fe, Hg, Mn, Pb, Se, and Zn in muscle samples of six fish species (Pygocentrus nattereri, Serrasalmus marginatus, Mylossoma duriventre, Leporinus friderici, Pimelodus argenteus, and P. pantaneiro) highly consumed by local riverine and non-resident people in middle Miranda River, southern Brazilian Pantanal. Significant differences were detected for Ba, Fe, Mn, and Zn levels among the analyzed species. Pairwise comparison detected significant differences in element levels between species with similar diets, which implies that other factors, instead of species' feeding habits, could be involved in distinct levels of element bioaccumulation. Significant correlations between body size and concentrations were found for Ba in P. nattereri (moderate positive correlation), and for Mn in M. duriventre (weak positive correlation) and P. argenteus (moderate negative correlation). Levels exceeding tolerable daily intake (TDI) were found for Pb maximum concentrations in P. nattereri, M. duriventre, L. friderici, P. argenteus, and P. pantaneiro, and for Cd maximum concentration in P. argenteus. Health risk assessment indicated considerable risk only for the worst-case scenario (calculated from maximum concentrations) for all species. Adopting a Pb monitoring program in biotic and abiotic compartments in Miranda River is strongly recommended.

Assessment of toxic elements in selected fish species in the marine water at Jamestown, Ghana

Fish is an excellent source of low-fat protein. Fish contains a lot of omega-3 fatty acids, as well as vitamins D and B2 (riboflavin). The daily consumption of contaminated food, especially fish, is among the primary cause of heavy metals pollution to human health. The aim of the research was to determine the concentration of heavy metals in selected species of fish from the Gulf of Guinea at James Town in Ghana. In tandem with the study's objective, samples of different forms of fish, Cassava fish, Flatfish, Redfish, Kingfish, and Silverfish, and sediment were obtained and analyzed for the presence of heavy metals using atomic absorption spectrometer (PerkinElmer®, PinAAcle 900T). The analysis indicated a high concentration of Pb, Cd, and Cr concentrations in fish gills, muscles, and sediment. High lead concentration in Silverfish gills (5.9 mg/kg) and Flatfish gills (2.29 mg/kg) above WHO levels. Cadmium was found in all fish species and sediment except Kingfish. Chromium concentrations were high n Cassava fish (3.10 mg/kg) and Silverfish (4.01 mg/kg) and copper concentrations were absent in the fish species. Arsenic and mercury were also not detected in all fish species and sediment. Manganese concentrations were found in fish and sediment. High cadmium target hazard quotient (0.17-11.60 for adults and 0.24 to 16.24 for children) and cancer risk (0.00-0.04) values in fish samples indicated potential health concerns. The Hazard Index (HI) for the analyzed samples ranged from 0.00 to 12.48 for adults and 0.00 to 17.47 for children. The study suggests that eliminating pollution and other sources of waterbody pollution is crucial to protecting the marine environment and the health of seafood consumers.

Composition of heavy metals in sediment, water, and fish of the Ganga and Yamuna Rivers in two major cities of India

The rapid industrial development in the Indian capital region has led to significant waste generation, which, despite undergoing treatment prior to disposal, contributes substantially to water body contamination. Given the diverse nature of these wastes and their potential repercussions across the food chain, a study was conducted to evaluate heavy metal contamination levels in the Ganga and Yamuna Rivers of two major cities. Six heavy metals (Pb, Cd, Hg, Cu, Cr, and Zn) were analyzed in fish, water, and sediment samples by utilizing flame atomic absorption spectrophotometry (Avanta Σ) from March 2019 to February 2020. Results revealed distinct heavy metal distribution patterns, with Cr > Zn > Pb > Cu > Cd > Hg in the Ganga River and Zn > Cr > Pb > Cu > Cd > Hg in the Yamuna River for fish samples. Additionally, levels of Hg in Cyprinus carpio and Sperata oar from the Ganga River, and Pb, Cd, Hg, and Cr in Salmophasia bacaila and Mystus cavasius from the Yamuna River exceeded WHO/FAO permissible limits. In water samples, the predominant heavy metal sequences were Pb > Cu > Zn > Cr > Cd > Hg for the Ganga River and Cr > Zn > Pb > Cu > Cd > Hg for the Yamuna River, with Pb, Cr, Zn, and Cd surpassing WHO standards. Sediment analysis revealed varying heavy metal compositions, with Zn > Cr > Pb > Cu > Cd > Hg in the Ganga River and Cr > Zn > Pb > Cu > Cd > Hg in the Yamuna River. While drinking water and fish from the Ganga River were deemed safe for consumption, those from the Yamuna River were not. Given the toxic nature of heavy metals and their detrimental health impacts, regular monitoring and effective management strategies are imperative.

Stevioside mitigates lead toxicity in thinlip mullet juveniles: Impacts on growth, metabolism, and immune function

This study investigates the impact of varying concentrations of stevioside in the presence of lead (Pb) exposure on multiple aspects of thinlip mullet (Liza ramada) juveniles. Over 60 days, a total of 540 juvenile L. ramada with an initial weight of 3.5 ± 0.13 g were evenly distributed into six groups, each consisting of three replicates. The experimental diet consisted of varying levels of stevioside (150, 250, 350, and 450 mg/kg diet), with a consistent concentration of lead (Pb) set at 100 µg/kg diet. Stevioside demonstrated a positive influence on growth parameters, with the 450 mg/kg +Pb treatment showing the highest values. Biochemical parameters remained stable, but lead-exposed fish without stevioside displayed signs of potential liver damage and metabolic issues. Stevioside supplementation, especially at higher doses (≥250 mg/kg), reversed these negative effects, restoring biochemical markers to healthy control levels. Lead exposure significantly suppressed antioxidant enzyme activities, but co-administration of stevioside exhibited a dose-dependent protective effect, with 250, 350, and 450 mg/kg groups showing activities comparable to the healthy control. Lead-exposed fish without stevioside demonstrated attenuation of the immune response, but stevioside supplementation reversed these effects, particularly at ≥250 mg/kg. Stev (≥250 mg/kg) reduced IL-1β and hepcidin expression, contrasting dose-dependent upregulation in lower dosages and lead-only group. Histological examinations of the intestine and liver supported these findings. In conclusion, stevioside, especially at 450 mg, positively impacted growth, biochemical parameters, antioxidant activity, immune response, and gene expression in L. ramada exposed to lead, suggesting its potential to mitigate lead toxicity in aquaculture. Additional research is warranted to investigate the long-term impacts of stevioside supplementation and its prospective implementation in aquaculture.

Sustainable adsorbent frameworks based on bio-resourced materials and biodegradable polymers in selective phosphate removal for waste-water remediation

Phosphorus to an optimum extent is an essential nutrient for all living organisms and its scarcity may cause food security, and environmental preservation issues vis-à-vis agroeconomic hurdles. Undesirably excess phosphorus intensifies the eutrophication problem in non-marine water bodies and disrupts the natural nutrient balance of the ecosystem. To overcome such dichotomy, biodegradable polymer-based adsorbents have emerged as a cost-effective and implementable approach in striking a "desired optimum-undesired excess" balance pertaining to phosphate in a sustainable manner. So far, the reports on adopting such adsorbent-approach for wastewater remediation remained largely scattered, unstructured, and poorly correlated. In this background, the contextual review comprehensively discusses the current state-of-the-art in utilizing biodegradable polymeric frameworks as an adsorbent system for phosphate removal and its efficient recovery from the aquatic ecosystem, while highlighting their characteristics-specific functional efficiency vis-à-vis easiness of synthetic and commercial viability. The overview further delves into the sources and environmental ramifications of excessive phosphorus in water bodies and associated mechanistic pathways of phosphorus removal via adsorption, precipitation, and membrane filtration enabled by biodegradable (natural and synthetic) polymeric substrates. Finally, functionality optimization, degradability tuning, and adsorption selectivity of biodegradable polymers are highlighted, while aiming to strike a balance in "removal-recovery-reuse" dynamics of phosphate. Thus, the current review not only paves the way for future exploration of biodegradable polymers in sustainable cost-effective adsorbents for phosphorus removal but also can serve as a guide for researchers dealing with this critical issue.

Ecological and public health risk assessment of potentially toxic elements in the surface sediments of the Pasur river estuary, Bangladesh

Potentially toxic elements (PTEs) in the surface sediments of the Pasur river estuary was investigated to assess its distribution, potential sources, and current dangers to ecological and public health. The Pasur River is a tidal, meandering, perennial river in south-western Bangladesh with a considerable number of fisheries and industrial activities. Sediment samples were collected from seven sampling points from January to December 2022 to assess the contamination level of six potentially toxic elements (Pb, Cr, Cd, As, Cu and Zn). Flame Atomic Absorption Spectrophotometer was utilized to detect the concentration of PTEs by following some sequential analytical procedure. Concentration of PTEs followed the reducing trend of Zn > Cr > Pb > As > Cu > Cd with the mean value of 61.04 > 49.15 > 26.58 > 10.28 > 6.28 > 1.59 mg/kg, respectively. The principle component and cluster analyses justified the anthropogenic source of the studied PTEs. The mean values of contamination factor (CF), geo-accumulation index (Igeo) and enrichment factor (EFc) showed that Pb and Cd were highly responsible for sediment (uncontaminated to moderate) contamination. Pollution load index (PLI) indicated higher pollution of sediments near the port areas. Potential ecological risk index (PERI) indicated low to moderate risks due to the contaminated sediment. However, the contamination of sediment was not associated with the non-carcinogenic (HQderm and HI < 1) and carcinogenic (CRderm < 10-6) risks due to the dermal contact. Although the risks were within the tolerable limit, regular monitoring is suggested to reduce the risk of PTEs contamination.

Heavy metal levels and human health risk implications associated with fish consumption from the lower Omo river (Lotic) and Omo delta lake (Lentic), Ethiopia

This study is the first to determine the levels of heavy metals in commercially important fish species, namely Lates niloticus and Oreochromis niloticus and the potential human health risks associated with their consumption. A total of 120 fish samples were collected from the lower Omo river and Omo delta, with 60 samples from each water source. The fish tissue samples (liver and muscle) were analyzed using a flame atomic absorption spectrometer for nine heavy metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn). The human health risk assessment tools used were the target hazard quotient (THQ), the hazard index (HI), and the target cancer risk (TCR). The mean levels of heavy metals detected in the liver and muscle of L. niloticus from the lower Omo river generally occurred in the order Fe > Zn > Pb> Cu > Mn> Cr > Co > Ni and Pb > Cu > Mn > Co > Ni, respectively. The mean levels of metals in the muscle and liver tissues of O. niloticus were in the order Fe > Pb > Zn > Mn > Cu > Cr > Co > Ni and Pb > Zn > Mn > Fe > Cu > Co > Ni, respectively. Similarly, the mean levels of heavy metals detected in the liver and muscle of L. niloticus from Omo delta occurred in the order Fe > Zn > Pb > Cu > Mn > Cr > Co > Ni and Fe > Pb > Zn > Mn > Cu > Co > Cr > Ni, respectively. The mean levels in the muscle and liver tissues of O. niloticus from the Omo delta were in the order Fe > Pb > Zn > Mn > Cu > Cr > Co > Ni and Pb > Fe > Zn > Mn > Co > Cu > Ni, respectively. The study revealed that the THQ values were below 1, indicating that consumption of L. niloticus and O. niloticus from the studied sites does not pose a potential non-carcinogenic health risk. Although the TCR values for Pb in this study were within the tolerable range, it's mean concentration in the muscle and liver tissues of both fish species from the two water bodies exceeded the permissible limit established by FAO/WHO. This is a warning sign for early intervention, and it emphasizes the need for regular monitoring of freshwater fish. Therefore, it is imperative to investigate the pollution levels and human health risks of heavy metals in fish tissues from lower Omo river and Omo delta for environmental and public health concerns.

Emerging insights into the impacts of heavy metals exposure on health, reproductive and productive performance of livestock

Heavy metals, common environmental pollutants with widespread distribution hazards and several health problems linked to them are distinguished from other toxic compounds by their bioaccumulation in living organisms. They pollute the food chain and threaten the health of animals. Biologically, heavy metals exhibit both beneficial and harmful effects. Certain essential heavy metals such as Co, Mn, Se, Zn, and Mg play crucial roles in vital physiological processes in trace amounts, while others like As, Pb, Hg, Cd, and Cu are widely recognized for their toxic properties. Regardless of their physiological functions, an excess intake of all heavy metals beyond the tolerance limit can lead to toxicity. Animals face exposure to heavy metals through contaminated feed and water, primarily as a result of anthropogenic environmental pollution. After ingestion heavy metals persist in the body for an extended duration and the nature of exposure dictates whether they induce acute or chronic, clinical or subclinical, or subtle toxicities. The toxic effects of metals lead to disruption of cellular homeostasis through the generation of free radicals that develop oxidative stress. In cases of acute heavy metal poisoning, characteristic clinical symptoms may arise, potentially culminating in the death of animals with corresponding necropsy findings. Chronic toxicities manifest as a decline in overall body condition scoring and a decrease in the production potential of animals. Elevated heavy metal levels in consumable animal products raise public health concerns. Timely diagnosis, targeted antidotes, and management strategies can significantly mitigate heavy metal impact on livestock health, productivity, and reproductive performance.

Accumulation of potentially toxic elements in fourfinger threadfin (Eleutheronema tetradactylum) and black pomfret (Parastromateus niger) from Selangor, Malaysia

The accumulation of potentially toxic elements (PTEs) has raised public awareness due to harmful contamination to both human and marine creatures. This study was designed to determine the concentration of copper (Cu), zinc (Zn), cadmium (Cd), and nickel (Ni) in the intestine, kidney, muscle, gill, and liver tissues of local commercial edible fish, fourfinger threadfin (Eleutheronema tetradactylum), and black pomfret (Parastromateus niger) collected from Morib (M) and Kuala Selangor (KS). Among the studied PTEs, Cu and Zn were essential elements to regulate body metabolism with certain dosages required while Cd and Ni were considered as non-essential elements that posed chronic and carcinogenic risk. The concentration of PTEs in fish tissue samples was analyzed using flame atomic absorption spectrometry (F-AAS). By comparing the concentration of PTEs in fish tissues as a bioindicator, the environmental risk of Morib was more serious than Kuala Selangor because both fish species collected from Morib resulted in a higher PTEs concentration. For an average 62 kg adult with a fish ingestion rate (FIR) of 0.16 kg/person/day in Malaysia, the estimated weekly intake (EWI) of Cd from the consumption of E. tetradactylum (M: 0.0135 mg/kg; KS: 0.0134 mg/kg) and P. niger (M: 0.0140 mg/kg; KS: 0.0132 mg/kg) had exceeded the provisional tolerable weekly intake (Cd: 0.007 mg/kg) established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) and oral reference dose (ORD) values of Cd (0.001 mg/kg/day) as provided by the United States Environmental Protection Agency (USEPA) regional screening level, thus it posed chronic risks for daily basis consumption. Besides, the value of the carcinogenic risk of Cd (0.7-3 to 0.8-3) and Ni (0.5-3 to 0.6-3) were in between the acceptable range (10-6 to 10-4) of the health index that indicates a relatively low possibility cancer occurrence to the consumers in both Morib and Kuala Selangor. This study recommended FIR to be 0.80 kg/person/day to reduce the possibility of posing chronic and carcinogenic risks while at the same time obtaining the essential nutrients from the fish.

WITHDRAWN: Trace metals translocation from soil to plants: Health risk assessment via consumption of vegetables in the urban sprawl of a developing country

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Bioaccumulation of Potentially Toxic Elements in Commercially Important Food Fish Species from Lower Gangetic Stretch: Food Security and Human Health Risk Assessment

Ganga river is the inhabitant of more than 190 fish species and important river system of India. Potentially toxic elements (PTEs) in the Gangetic riverine ecosystem are a hot environmental issue. A detailed evaluation of PTEs bioaccumulation in Gangetic fishes is required to safeguard human health. The present study investigated the bioaccumulation of PTEs (Cd, Co, Cr, Cu, Li, Ni, Pb, Se, Zn, and Mn) within 12 economic fish species (n = 72) collected from the lower Gangetic stretch. The mean concentrations of PTEs followed the order Zn > Cu > Mn > Ni > Se > Cr > Pb > Co ~ Li > Cd. Li and Se bioaccumulation were studied first time from Gangetic fishes. Results demonstrated that all the selected PTEs were below the maximum permissible limit recommended by reference standards except for Zn in L. catla and L. rohita. For all PTEs, the metal pollution index (MPI), hazard quotient (THQ), and hazard index (HI) were < 1, indicating that these PTEs do not pose a health risk to the public through the dietary intake of fish in this study area. All studied fish were acceptable in terms of carcinogenic risk (CR) from exposure to Cd, Cr, and Pb. Multivariate statistical analysis suggests that inter-correlated metals have similar dispersion properties and bioaccumulation homology within the body. This study provides a scientific basis for food safety assessment and continuous monitoring of PTEs in Gangetic fishes is suggested in the future to safeguard human health.

Seasonal Variation and Association of Heavy Metals in the Vital Organs of Edible Fishes from the River Jhelum in Punjab, Pakistan

The toxic effects of heavy metals are drastic, including accumulation. Fish species are important bio-indicators of heavy metal pollution in aquatic bodies. The current study aimed to assess the seasonal variation of heavy metals in the vital organs of mostly consumed fishes in River Jhelum, Pakistan. Samples of fish, including Wallago attu (Malhi), Rita rita (Khagga), and Mystus seenghala (Singhari), were collected from four different sites, i.e., Khushab, Muhammad Wala (M. Wala), 8.R.D and Rasool barrage during summer and winter seasons. Heavy metals such as iron (Fe), lead (Pb), chromium (Cr), cobalt (Co) and Cadmium (Cd) were estimated through acid digestion and spectrometric analysis. Results showed a significantly higher (P < 0.05) amount of these metals in the liver, followed by the kidneys of fish species. There were seasonal variations in the absorption of these metals as well. Cr (11.71) and Fe (58.66) were detected in higher amounts in Khagga which showed the greatest affinity for certain metals in some cases. In contrast, Singhari showed the greatest affinity to other metals in other cases. Comparative analysis revealed that there was a highly significant (P < 0.05) difference for the accumulation of almost all metals in both seasons and summer had the highest concentration of Cd, Pb, Co, Cr and Fe as compared to winter in all four sampling stations in the case of kidney and liver of all the three fishes. Elevated levels of heavy metals were detected in the summer due to increased temperature. Heavy metals found in the River Jhelum may demonstrate that metals can significantly affect the fish species.

Unraveling the impact of digital transformation on green innovation through microdata and machine learning

How to use digitalization to support the green transformation of organizations has drawn much attention based on the rapid development of digitalization. However, digital transformation (DT) may be hindered by the "IT productivity paradox." Exploring the influence of DT on green innovation, we analyze panel data encompassing A-share listed companies in Shanghai and Shenzhen spanning the period from 2010 to 2018. It tests the DT's non-linear impact, employing a random-forest and mediation effect models. The results reveal that (i) DT can promote green innovation; (ii) regarding heterogeneity, the promotion effect is mainly manifested in enterprises in non-state-owned and highly competitive industries; (iii) based on mechanism testing, DT relies on two routes to encourage green innovation: improving environmental information disclosure and reducing environmental uncertainty; and (iv) random-forest analysis shows that DT exhibits an inverted U-shaped non-linear effect on green innovation, including the "IT productivity paradox." This study enhances the existing discourse on DT and green innovation by furnishing empirical substantiation for the non-linear influence exerted by DT on green innovation. Furthermore, it imparts insights into the mechanisms and contextual limitations governing this association.

Assessment of heavy metals accumulation by vegetables irrigated with different stages of textile wastewater for evaluation of food and health risk

Wastewater irrigation for vegetable cultivation is greatly concerned about the presence of toxic metals in irrigated soil and vegetables which causes possible threats to human health. This study aimed to ascertain the accumulation of heavy metals (HMs) in edible parts of vegetables irrigated with different stages of textile dyeing wastewater (TDW). Bio-concentration factor (BCF), Estimated daily intake (EDI), and target hazard quotient (THQ) were computed to estimate human health risks and speculate the hazard index (HI) of adults and children with the consumption of HMs contaminated vegetables at recommended doses. Five vegetables (red amaranth, Indian spinach, cauliflower, tomato, and radish) in a pot experiment were irrigated with groundwater (T1) and seven stages of TDW (T2∼T8) following a randomized complete block design (RCBD) with three replications. Among the TDW stages, T8, T7, T4, and T5 exhibited elevated BCF, EDI, THQ, and HI due to a rising trend in the accumulation of Pb, Cd, Cr, and Ni heavy metals in the edible portion of the red amaranth, followed by radish, Indian spinach, cauliflower, and tomato. The general patterns of heavy metal (HM) accumulation, regarded as vital nutrients for plants, were detected in the following sequence: Zn > Mn/Cu > Fe. Conversely, toxic metals were found to be Cd/Cr > Ni > Pb, regardless of the type of vegetables. Principal Component Analysis (PCA) identified T8, T7, and T4 of TDW as the primary contributors to the accumulation of heavy metals in the vegetables examined. Furthermore, the analysis of the heavy metals revealed that the BCF, THQ, and HI values for all studied metals were below 1, except for Pb. This suggests that the present consumption rates of different leafy and non-leafy vegetables, whether consumed individually or together, provide a low risk in terms of heavy metal exposure. Nevertheless, the consumption of T8, T7, and T4 irrigated vegetables, specifically Indian spinach alone or in combination with red amaranth and radish, by both adults and children, at the recommended rate, was found to pose potential health risks. On the other hand, T2, T3, and T6 irrigated vegetables were deemed safe for consumption. These findings indicated that the practice of irrigating the vegetables with T8, T7, and T4 stages of TDW has resulted in a significant buildup of heavy metals in the soils and edible parts of vegetables which are posing health risks to adults and children. Hence, it is imperative to discharge the T8, T7, and T4 stages of TDW after ETP to prevent the contamination of vegetables and mitigate potential health risks.

Review of the Terminology, Approaches, and Formulations Used in the Guidelines on Quantitative Risk Assessment of Chemical Hazards in Food

This paper reviews the published terminology, mathematical models, and the possible approaches used to characterise the risk of foodborne chemical hazards, particularly pesticides, metals, mycotoxins, acrylamide, and polycyclic aromatic hydrocarbons (PAHs). The results confirmed the wide variability of the nomenclature used, e.g., 28 different ways of referencing exposure, 13 of cancer risk, or 9 of slope factor. On the other hand, a total of 16 equations were identified to formulate all the risk characterisation parameters of interest. Therefore, the present study proposes a terminology and formulation for some risk characterisation parameters based on the guidelines of international organisations and the literature review. The mathematical model used for non-genotoxic hazards is a ratio in all cases. However, the authors used the probability of cancer or different ratios, such as the margin of exposure (MOE) for genotoxic hazards. For each effect studied per hazard, the non-genotoxic effect was mostly studied in pesticides (79.73%), the genotoxic effect was mostly studied in PAHs (71.15%), and both effects were mainly studied in metals (59.4%). The authors of the works reviewed generally opted for a deterministic approach, although most of those who assessed the risk for mycotoxins or the ratio and risk for acrylamide used the probabilistic approach.

Environment-relevant concentrations of cadmium induces necroptosis and inflammation; baicalein maintains gill homeostasis through suppressing ROS/ER stress signaling in common carps (Cyprinus carpio L.)

Cadmium (Cd) is a major contaminant in natural environments and exerts adverse effects on aquatic biota at low concentrations. Gill is as vital respiratory organ and may cause pollutants to enter fish during gas exchange. Baicalein (BAI), as a kind of flavonoids, possess antioxidant properties through inactivating free radicals. To confirm the potential effects and approaches of BAI addition in maintaining the gill stability, 90 common carps (Cyprinus carpio L.) were selected and randomly divided into water environment exposure group (0.22 mg/L Cd) and/or feed added with 0.10 g/kg BAI for 30 days. The analysis of ion content in serum showed that Cd exposure disturbed ion homeostasis, and BAI could reduce serum Cd concentration. The histopathological results of gills showed that Cd exposure caused gill tissue lesions and structural damage, and BAI feeding effectively alleviated this damage. In addition, BAI could enhance antioxidant activity and activate Nrf2/HO-1 axis, thereby reducing oxidative stress and endoplasmic reticulum (ER) stress. Moreover, BAI lightened cytokine imbalance, inflammatory response, and necroptosis. Overall, the results indicated that BAI feeding could maintain gill homeostasis against Cd poisoning via the ROS/ER stress signaling. This trial revealed the properties of BAI resistance to metal Cd in aquaculture and partially elucidated its mechanism.

Bioaccumulation and sources of metal(loid)s in fish species from a subtropical river in Bangladesh: a public health concern

Toxic metals and freshwater fish's metalloid contamination are significant environmental concerns for overall public health. However, the bioaccumulation and sources of metal(loids) in freshwater fishes from Bangladesh still remain unknown. Thus, the As, Pb, Cd, and Cr concentrations in various freshwater fish species from the Rupsha River basin were measured, including Tenualosa ilisha, Gudusia chapra, Otolithoides pama, Setipinna phasa, Mystus vittatus, Glossogobius giuris, and Pseudeutropius atherinoides. An atomic absorption spectrophotometer was used to determine metal concentrations. The mean concentrations of metal(loids) in the fish muscle (mg/kg) were found to be As (1.53) > Pb (1.25) > Cr (0.51) > Cd (0.39) in summer and As (1.72) > Pb (1.51) > Cr (0.65) > Cd (0.49) in winter. The analyzed fish species had considerably different metal(loid) concentrations with seasonal variation, and the distribution of the metals (loids) was consistent with the normal distribution. The demersal species, M. vittatus, displayed the highest bio-accumulative value over the summer. However, in both seasons, none of the species were bio-accumulative. According to multivariate statistical findings, the research area's potential sources of metal(loid) were anthropogenic activities linked to geogenic processes. Estimated daily intake, target hazard quotient (THQ), and carcinogenic risk (CR) were used to assess the influence of the risk on human health. The consumers' THQs values were < 1, indicating that there were no non-carcinogenic concerns for local consumers. Both categories of customers had CRs that fell below the permissible range of 1E - 6 to 1E - 4, meaning they were not at any increased risk of developing cancer. The children's group was more vulnerable to both carcinogenic and non-carcinogenic hazards. Therefore, the entry of metal(loids) must be regulated, and appropriate laws must be used by policymakers.

The comparison and analysis of nutritional qualities of Chinese mitten crabs (Eriocheir sinensis) in rice field and pond culture modes

The nutritional quality of three edible parts (gonads, hepatopancreas and muscles) of Chinese mitten crabs (CMCs) from rice field culture and pond culture was firstly compared in our current study. It was found that the contents of mineral elements and volatile compounds in rice CMCs were superior to those in pond CMCs, and the antioxidant enzyme activities of rice CMCs were markedly higher than those of pond CMCs. Besides, the total free amino acid levels in the edible parts of pond CMCs were higher than those of rice CMCs. Compared with other tissues, the nucleotide and equivalent umami concentrations of the gonads in female rice CMCs were the maximum. Overall, both types of crabs demonstrated good nutritional quality, which met human nutrition and dietary needs. In comparison, the quality of rice CMCs was better than that of pond CMCs.

Ecological risk assessment for metals in sediment and waters from the Brazilian Amazon region

Pollution by metals is a matter of concern around the world. In recent decades, the high population growth in urban centers has significantly magnified the entry of these pollutants into aquatic ecosystems. The Amazon region, intense migratory flow, gold mining, and industrialization have been considered the main driving forces for increasing metal pollution. Thus, the main aim of this study is to conduct, for the first time, an Ecological Risk Assessment (ERA) based on metal concentrations measured in the sediment and water of several aquatic environments from the Amazon basin, based on the risk quotient values (RQ = measured environmental concentration - MEC/predicted no effect concentration - PNEC). In addition, the metal contamination factor (CF) was estimated. Although metal concentrations in water were generally low, these values were far above the limits established by current national legislation in many areas, showing higher concentrations for the metals Co, Pb, Cr, Cu, and Ni. Concentrations of Mn, Cu, Ba, Pb, Co, Ni, Cr, Zn, Cd, and As were especially high in the sediment for several evaluated environments. The ERA for the water compartment revealed that 56% of the studied areas presented high risk (RQ > 1) for aquatic biota. In the sediment, 66% of the sites presented a high risk and 40% medium risk (RQ = 0.1-1). The CF indicated that 49% of the sampling points had high contamination and only 24%, had low contamination. These results reveal that monitoring studies in the Amazon region, provides important information so that public policies for the preservation of water resources can be strengthened in the Amazon.

Evaluation of water quality and bioaccumulation of metals in commercially important fishes: a human health concern

The present study aimed to determine the physicochemical properties of the coastal water and metal concentration in the muscle tissues of five commercially important fish species (Leiognathus equulus, Lates calcarifer, Sillago sihama, Scolopsis bimaculatus, Lutjanus fulviflamma) along Thondi coast, as well as the potential human health risks on consumption of these species were also studied. Water quality parameters, such as mean temperature (31.3 ± 1.86 °C), salinity (28.35 ± 0.79‰), pH (7.95 ± 0.22), TDS (12840 ± 1.49 mg L-1), TSS (310 ± 0.51 mg L-1) and DO (5.99 ± 0.14 mg L-1) were obtained. Various nutrients such as calcium (300.0 ± 36.05 mg L-1), inorganic phosphate (0.186 ± 0.02 μg L-1), magnesium (1077.6 ± 107.01 mg L-1), nitrate (1.584 ± 0.31 μg L-1), nitrite (1.179 ± 0.34 μg L-1), silicate (29.717 ± 1.93 μg L-1) and total phosphorus (0.153 ± 0.08 μg L-1) were also analysed. The concentration of metals As, Cd, Cr, Cu, Pb and Zn in the muscle tissue was determined using atomic absorption spectroscopy (AAS). Arsenic, Cu and Pb were found to be highest in S. sihama; 1.2364 ± 0.12, 1.6102 ± 0.28 and 1.0103 ± 0.21 μg/g respectively. Cadmium and Zn were found maximum in S. bimaculatus; 0.0876 ± 0.04 and 1.0564 ± 0.16 μg/g respectively, whereas Cr was found highest in L. Calcarifer; 1.6781 ± 0.18 μg/g. Compared our results with FAO/WHO/EU regulations. The estimated daily intake (EDI) specifies that there is no risk of consuming these species. However, the target hazard quotient (THQ) in As is found to be > 1 in these fish species, which implies a possible danger to consumers.

Microbial Biosurfactant: Candida bombicola as a Potential Remediator of Environments Contaminated by Heavy Metals

Industrial interest in surfactants of microbial origin has intensified recently due to the characteristics of these compounds, such as biodegradability and reduced toxicity, and their efficiency in removing heavy metals and hydrophobic organic compounds from soils and waters. The aim of this study was to produce a biosurfactant using Candida bombicola URM 3712 in a low-cost medium containing 5.0% molasses, 3.0% corn steep liquor and 2.5% residual frying oil for 144 h at 200 rmp. Measurements of engine oil tension and emulsification were made under extreme conditions of temperature (0 °C, 5 °C, 70 °C, 100 °C and 120 °C), pH (2-12) and NaCl concentrations (2-12), demonstrating the stability of the biosurfactant. The isolated biosurfactant was characterized as an anionic molecule with the ability to reduce the surface tension of water from 72 to 29 mN/m, with a critical micellar concentration of 0.5%. The biosurfactant had no toxic effect on vegetable seeds or on Eisenia fetida as a bioindicator. Applications in the removal of heavy metals from contaminated soils under dynamic conditions demonstrated the potential of the crude and isolated biosurfactant in the removal of Fe, Zn and Pb with percentages between 70 and 88%, with the highest removal of Pb being 48%. The highest percentage of removal was obtained using the cell-free metabolic liquid, which was able to remove 48, 71 and 88% of lead, zinc and iron from the soil, respectively. Tests in packed columns also confirmed the biosurfactant's ability to remove Fe, Zn and Pb between 40 and 65%. The removal kinetics demonstrated an increasing percentage, reaching removal of 50, 70 and 85% for Pb, Zn and Fe, respectively, reaching a greater removal efficiency at the end of 24 h. The biosurfactant was also able to significantly reduce the electrical conductivity of solutions containing heavy metals. The biosurfactant produced by Candida bombicola has potential as an adjuvant in industrial processes for remediating soils and effluents polluted by inorganic contaminants.

Integrating chemical and biological data by chemometrics to evaluate detoxification responses of a neotropical bivalve to metal and metalloid contamination

Mangroves represent a challenge in monitoring studies due to their physical and chemical conditions under constant marine and anthropogenic influences. This study investigated metals/metalloids whole-body bioaccumulation (soft tissues) and the risk associated with their uptake, biochemical and morphological detoxification processes in gills and metals/metalloids immobilisation in shells of the neotropical sentinel oyster Crassostrea rhizophorae from two Brazilian estuarine sites. Biochemical and morphological responses indicated three main mechanisms: (1) catalase, superoxide dismutase and glutathione played important roles as the first defence against reactive oxygen species; (2) antioxidant capacity against peroxyl radicals, glutathione S-transferase, metallothionein prevent protein damage and (3) metals/metalloids sequestration into oyster shells as a mechanism of oyster detoxification. However, the estimated daily intake, target hazard quotient, and hazard index showed that the human consumption of oysters would not represent a human health risk. Among 14 analysed metals/metalloids, chemometrics indicate that Mn, As, Pb, Zn and Fe overload the antioxidant system leading to morphological alterations in gills. Overall, results indicated cellular vacuolization and increases in mucous cell density as defence mechanisms to prevent metals/metalloids accumulation and the reduction in gill cilia; these have long-term implications in respiration and feeding and, consequently, for growth and development. The integration of data from different sites and environmental conditions using chemometrics highlights the main biological patterns of detoxification from a neotropical estuarine bivalve, indicating the way in which species can cope with metals/metalloids contamination and its ecological consequences.

Bio-based functionalized adsorptive polymers for sustainable water decontamination: A systematic review of challenges and real-world implementation

The overwhelming concerns of water pollution, industrial discharges and environmental deterioration by various organic and inorganic substances, including dyes, heavy metals, pesticides, pharmaceuticals, and detergents, intrinsically drive the search for urgent and efficacious decontamination techniques. This review illustrates the various approaches to remediation, their fundamentals, characteristics and demerits. In this manner, the advantageous implementation of nature-based adsorbents has been outlined and discussed. Different types of lignocellulosic compounds (cellulose, lignin, chitin, chitosan, starch) have been introduced, and the most used biopolymeric materials in bioremediation have been highlighted; their merits, synthesis methods, properties and performances in aqueous medium decontamination have been described. The literature assessment reveals the genuine interest and dependence of academic and industrial fields to valorize biopolymers in the adsorption of various hazardous substances. Yet, the full potential of this approach is still confined by certain constraints, such as the lack of reliable, substantial, and efficient extraction of biopolymers, as well as their modest and inconsistent physicochemical properties. The futuristic reliance on such biomaterials in all fields, rather than adsorption, is inherently reliable on in-depth investigations and understanding of their features and mechanisms, which can guarantee a real-world application and green technologies.

Heavy metals in five commonly consumed fish species from River Swat, Pakistan, and their implications for human health using multiple risk assessment approaches

This study analyzed the levels of heavy metals bioaccumulation in commonly consumed riverine fish species, including G. cavia, T. macrolepis, G. gotyla, S. plagiostomus, and M. armatus from River Swat in Pakistan, and quantify their potential risk to children and adults in general and fisherfolk communities using multiple pollution and risk assessment approaches. The highest metal detected by inductive coupled plasma mass spectrometry (ICP-MS) was Zn, which ranged from 49.61 to 116.83 mg/kg, followed by Fe (19.25-101.33 mg/kg) > Mn (5.25-40.35 mg/kg) > Cr (3.05-14.59 mg/kg) > Ni (4.26-11.80 mg/kg) > Al (1.59-12.25 mg/kg) > Cu (1.24-8.59 mg/kg) > Pb (0.29-1.95 mg/kg) > Co (0.08-0.46 mg/kg) > Cd (0.01-0.29 mg/kg), demonstrating consistent fluctuation with the safe recommendations of global regulatory bodies. The average bioaccumulation factor (BAF) values in the examined fish species were high (BAF > 5000) for Pb, Zn, Mn, Cu, Cr, Ni, and Cd, bioaccumulate (1000 > BAF < 5000) for Co, and probable accumulative (BAF <1000) for Fe, and Al, while the overall ∑heavy metals pollution index (MPI) values were greater than one (MPI > 1) indicating sever heavy metals toxicity in G. cavia, followed by S. plagiostomus, M. armatus, G. gotyla, and T. macrolepis. The multivariate Pearson's correlation analysis identified the correlation coefficients between heavy metal pairs (NiCr, CuCr, PbCr, AlCo, CuNi, and PbNi), the hierarchical cluster analysis (CA) determined the origin by categorizing heavy metal accumulation into Cluster-A, Cluster-B, and Cluster-C, and the principal component analysis (PCA) discerned nearby weathering, mining, industrial, municipal, and agricultural activities as the potential sources of heavy metals bioaccumulation in riverine fish. As per human risk perspective, S.plagiostomus contributed significantly to the estimated daily intake (EDI) of heavy metals, followed by G.cavia > M.armatus > G.gotyla > T.macrolepis in dependent children and adults of the fisherfolk followed by the general population. The non-carcinogenic target hazard quotient (THQ) and hazard index (HI) values for heavy metal intake through fish exposure were < 1, while the carcinogenic risk (CR) for individual metal intake and the total carcinogenic risk (TCR) for cumulative Cr, Cd, and Pb intake were within the risk threshold of 10-6-10-4, suggesting an acceptable to high non-carcinogenic and carcinogenic risk for both children and adults in the fisherfolk, followed by the general population.

Spatio-temporal Sediment Quality Risk Assessment by Using Ecological and Statistical Indicators: A Review of the Upper Sakarya River, Türkiye

In this study, heavy metal accumulation levels (Cu, Zn, Cr, Pb, As) in biotic [Carassius gibelio (Bloch, 1782), Squalius pursakensis (Hankó 1925)] and abiotic (sediments) components in a significant freshwater ecosystem in Türkiye were investigated on the basis of seasonal variations using geographic information systems (GIS) and some ecotoxicological risk assessment indices [PLI (pollution load index), PERI (potential ecological risk index), Igeo (geo accumulation index), CF (contamination factor) and BRI (Biological Risk Index)]. GIS-based maps were utilized to depict the distribution of ecotoxicological risk assessment indices to provide a visual explanation by using the Inverse Distance Weighted (IDW) as an estimation method. Samples were collected seasonally from 12 stations selected on the Upper Sakarya River Basin, which is one of the longest fluvial ecosystems in Türkiye. As a result of applied indices, cadmium was found as the most hazardous heavy metal in terms of PERI and CF, nickel was found as the most hazardous heavy metal in terms of BRI and arsenic was found as the most hazardous heavy metal in terms of Igeo. As a result of applied PCI, 2 statistically significant factors explained 81.31% of the total variance. It was also determined that levels of almost all the investigated heavy metals (except Zn) in muscle tissues of fishes were under the permissible limits of Turkish legislation and the FAO.

Human Health Risk Assessment for Exposure to Heavy Metals via Dietary Intake of Rainbow Trout in the Influence Area of a Smelting Facility Located in Peru

Abandoned mining-metallurgical sites can significantly impact the environment and human health by accumulating heavy metals in aquatic ecosystems. The water in the sub-basin near an abandoned smelting facility in the city of La Oroya, Peru, is primarily used for pisciculture. The objective of this study was to assess the risk to human health from exposure to heavy metals via dietary intake of rainbow trout (Oncorhynchus mykiss) in the influence area of a smelting facility located in the central Andean region of Peru. The bioconcentration factor, biosediment accumulation factor, and consumption risks were evaluated using the Monte Carlo method. The results showed that the concentrations of elements (Zn > Pb > Cu > As) in rainbow trout muscle did not exceed the maximum limit (ML). However, the water significantly exceeded the ML for Pb in all sectors and As in the lower and middle parts of the river. The concentration of Pb in sediments also significantly exceeded the ML in the upper and lower parts of the river. Consequently, rainbow trout consumption in the study area presents risks to human health due to the bioaccumulation of heavy metals, with a 1.27% carcinogenic risk in samples from the lower part of the river.

Analysis of the Mercury Content in Fish for Human Consumption in Poland

Mercury (Hg) is a metal with toxic effects on the environment, including living organisms. Organic Hg derivatives readily penetrate biological membranes and pose a particular health risk. Food of aquatic origin is the main source of human exposure to methylmercury (MeHg). In Poland, the consumption of fishery and aquaculture products has been gradually increasing. The aim of this study was to determine the content of Hg in fish intended for human consumption and purchased in Poland. The total Hg content of the edible parts of different species of marine and freshwater fish was analysed. The range of Hg content in all fish was 0.004-0.827 mg/kg, with an arithmetic mean of 0.084 mg/kg. The concentration of Hg in marine fish (0.100 mg/kg) was higher than in freshwater fish (0.063 mg/kg). The highest concentration of Hg was found in tuna. The Estimated Hazard Quotient (EHQ) calculated for the tuna samples analysed was >1. This may represent a potential health risk for consumers. The consumption of the other fish analysed was considered safe on the basis of the EHQ. The Hg content of the analysed fish samples did not exceed the current limits for food.

Metal Load of Potentially Toxic Elements in Tuna (Thunnus albacares)-Food Safety Aspects

The consumption of marine fishes has a positive effect on a consumer's health; however, it poses a potential risk due to their level of heavy metals in their body. Heavy metals can be naturally found in the environment, but their concentration can be increased with anthropogenic activities. Samples of tuna (Thunnus albacares) were collected at a fishery market. The potentially toxic elements (arsenic, cadmium, lead, and mercury) were determined with a validated method in the flesh of fish using inductively plasma optical emission spectrometry after microwave digestion. Generally, the average concentration of them was below the official limit values regulated by the European Union, except for lead. Based on the concentrations of arsenic (inorganic derivates: 0.05 ± 0.02 mg/kg) and cadmium (0.03 ± 0.01 mg/kg) in the tuna fish samples, and their calculated EDI values (As: 0.03-0.09 µg/kg/day; Cd: 0.05-0.07 µg/kg/day), the investigated food could be declared safe for human consumption. Generally, mercury content was below the official regulated limit, and the calculated EDI value was below the dietary reference value (0.3 μg/kg/day) in most of the samples (90%), exceeding it only in two samples (0.69 and 0.82 μg/kg/day); thus, they may not be harmful to the consumer. The concentration of lead above the official maximum limit (0.30 mg/kg) in 40% of tuna samples (0.30-1.59 mg/kg), as well as the exceeding of the dietary reference value for lead (adult: 0.16 μg/kg/day; children: 0.26 μg/kg/day) based on the calculated EDI values (0.28-1.49 μg/kg/day), draw attention to the importance of environmental pollution and the protection of consumers' health.

Detrimental influence of industrial effluents, especially heavy metals, on limnological parameters of water and nutritional profile in addition to enzymatic activities of fish, Sperata seenghala (Sykes, 1839) from diverse Ramsar sites, India (Punjab)

The present research was designed to determine the nutritive value of the liver and intestine of fish, Sperata seenghala, the impact of effluence load on limnological parameters of water and proximate composition of fish organs, especially on fatty acids, liver enzymatic activities, seasonal variations in the nutritional profile of fish, and to check and compare the pollution status of Ramsar sites in Punjab by calculating the water quality index, heavy metal pollution index, and metal index from June 2018 to August 2020. WQI of Harike wetland was found to be 53.95, which depicts that water quality in this region is "poor". At Nangal wetland, water quality index was reported to be "excellent" quality water and fit for the whole ecological unit. Overall heavy metal pollution index for Harike wetland was reported 174.569, whereas for Nangal wetland it was 5.994, depicting massive contaminant loads in a polluted region. MI value was also recorded as being higher (6.9336) in polluted habitat than in control habitat (0.8175). In fish liver, significant (p < 0.05) higher mean total lipids (6.73%), total proteins (3.98%), moisture (77.69%), ash (3.56%), and carbohydrates (3.79%) were observed in the samples from Nangal wetland than Harike wetland. A similar trend was reported in all biochemical contents of the fish intestine. Enzyme activities such as aspartate-aminotransferase and alanine-aminotransferase were significantly elevated (p < 0.05) in the specimens collected from the polluted region. The mean total n-3 (except in spring), n-6 polyunsaturated fatty acids (except in winter), and average monounsaturated and saturated fatty acids diminished significantly (p < 0.05) in the liver of fish from contaminated habitat than control site. In the intestine of fish collected from the polluted region, significant reductions in the mean total n-3 (except in autumn as well as summer), total n-6 PUFAs (in autumn and winter), and total SFAs were reported than control site.

Inorganic nutrients and heavy metals in some wild edible plants consumed by rural communities in Northern Uganda: Implications for human health

For centuries, wild edible plant species have sustained local communities across Africa by supplementing households' diets in seasons of food shortage. Wild edible plants contain inorganic nutrients, which are essential for the proper functioning of organisms. However, their nutritional contents have not been well researched and are generally poorly understood. This study aimed to quantify the levels of inorganic micro-and macronutrients as well as heavy metals (Mg, Ca, K, Fe, Zn, Cd, Hg and Pb) in selected wild edible plants traditionally consumed among the Acholi communities in northern Uganda, and associated health risks of consuming them. The leaves and young stems of 12 wild edible plants, viz: Acalypha rhomboidea, Asystacia gangetica, Crassocephalum sacrobasis, Crotalaria ochroleuca, Heterotis rotundifolia, Hibiscus cannabinus, Hibiscus sp., Hibiscus surattensis, Ipomoea eriocarpa, Maerua angolensis, Senna obtusifolia and Vigna membranacea were air-dried and crushed to powder. The powders were then macerated using aqua regia solution and analyzed in triplicates using the Atomic Absorption Spectrophotometry (AAS). The target hazard quotient (THQ) of Pb was calculated for non-carcinogenic health risks. Mg, Ca, K, Fe, Zn and Pb were detectable in all the wild edible plants sampled. All inorganic nutrients (mg/100gdw), were below the Recommended Daily Allowance (RDA); Mg (9.4 ± 0.19 to 10.4 ± 0.15), Ca (119 ± 5.82 to 1265 ± 14.9), Fe (3.29 ± 0.02 to 11.2 ± 0.09), Zn (0.52 ± 0.02 to 2.36 ± 0.03). Hg and Cd were below detectable limits in all the samples tested. The content of Pb (0.69 ± 0.11 to1.22 ± 0.07) was higher than the CODEX and EU limits of 0.1 ppm (0.001 mg/g) but was below the recommended threshold of 1. The health risk assessment revealed no potential hazards both in children and adults. However, there is a need to study the bioavailability of Pb when the vegetables are consumed due to factors such as indigestion and antinutritional compounds.

Metal Contaminants in Fish: Blood as a Potential Non-lethal Monitoring Tool

The use of fish to monitor metal contamination is well established, but existing studies often focus on internal tissues that require the sacrifice of organisms. Developing non-lethal methods is thus a scientific challenge to enable large scale biomonitoring of wildlife health. We explored blood as a potential non-lethal monitoring tool for metal contamination in brown trout (Salmo trutta fario) as a model species. First, we investigated differences in metal contamination loads (i.e., Cr, Cu, Se, Zn, As, Cd, Pb and Sb) in different blood components (whole blood, red blood cells and plasma). Whole blood was reliable to measure most metals, implying that blood centrifugation is not necessary, thus minimizing sample preparation time. Second, we measured the within individual distribution of metals across tissues (whole blood, muscle, liver, bile, kidney and gonads) to test if blood could be a reliable monitoring tool compared to other tissues. Results show that the whole blood was reliable compared to muscle and bile to measure the levels of metals such as Cr, Cu, Se, Zn, Cd and Pb. This study opens the possibility for future ecotoxicological studies in fish to use blood instead of internal tissues to quantify some metals, thus reducing the negative impacts of biomonitoring on wildlife.

Bioaccumulation and Bioremediation of Heavy Metals in Fishes-A Review

Heavy metals, the most potent contaminants of the environment, are discharged into the aquatic ecosystems through the effluents of several industries, resulting in serious aquatic pollution. This type of severe heavy metal contamination in aquaculture systems has attracted great attention throughout the world. These toxic heavy metals are transmitted into the food chain through their bioaccumulation in different tissues of aquatic species and have aroused serious public health concerns. Heavy metal toxicity negatively affects the growth, reproduction, and physiology of fish, which is threatening the sustainable development of the aquaculture sector. Recently, several techniques, such as adsorption, physio-biochemical, molecular, and phytoremediation mechanisms have been successfully applied to reduce the toxicants in the environment. Microorganisms, especially several bacterial species, play a key role in this bioremediation process. In this context, the present review summarizes the bioaccumulation of different heavy metals into fishes, their toxic effects, and possible bioremediation techniques to protect the fishes from heavy metal contamination. Additionally, this paper discusses existing strategies to bioremediate heavy metals from aquatic ecosystems and the scope of genetic and molecular approaches for the effective bioremediation of heavy metals.

Metal pollution in freshwater fish: A key indicator of contamination and carcinogenic risk to public health

Metals are micropollutants that cannot be degraded by microorganisms and are infiltrated into various environmental media, including both freshwater and marine water. Metals from polluted water are absorbed by many aquatic species, especially fish. Fish is a staple food in the diets of many regions in the world; hence, both the type and concentration of metals accumulated and transferred from contaminated water sources to fish must be determined and assessed. In this study, the heavy metal concentration was determined and assessed in fish collected from freshwater sources via published literature and Estimated of Daily Intake (EDI), Target hazard quotient (THQ), and Carcinogenic Risk (CR) analyses, aiming to examine the metal pollution in freshwater fish. The fish was used as a bioindicator, and Geographic information system (GIS)was sued to map the polluted regions. The results confirmed that Pb was detected in fish sampled at 28 locations, Cr at 24 locations, Cu and Zn at 30 locations, with values Pb detected ranging from 0.0016 mg kg^-1 to 44.3 mg kg^-1, Cr detected ranging from 0.07 mg kg^-1 to 27 mg kg^-1, Cu detected ranging from 0.031 mg kg^-1 to 35.54 mg kg-¹, and Zn detected ranging from 0.242 mg kg^-1 to 103.2 mg kg^-1. The strongest positive associations were discovered between Cu-Zn (r = 0.74, p < 0.05) and Cr-Zn (r = 0.57, p < 0.05). Spatial distribution maps depicting the consumption of fish as food and its corresponding Pb and Cr intake revealed a higher incidence of both carcinogenic and non-carcinogenic health concerns attributed to Pb and Cr in the region with populations consuming the fish.

Green synthesis of Fe3O4 nanoparticles using Alliaceae waste (Allium sativum) for a sustainable landscape enhancement using support vector regression

The synthesis of metal nanoparticles using green chemistry methods has gained significant attention in the field of landscape enhancement. Researchers have paid close attention to the development of very effective green chemistry approaches for the production of metal nanoparticles (NPs). The primary goal is to create an environmentally sustainable technique for generating NPs. At the nanoscale, ferro- and ferrimagnetic minerals such as magnetite exhibit superparamagnetic properties (Fe3O4). Magnetic nanoparticles (NPs) have received increased interest in nanoscience and nanotechnology due to their physiochemical properties, small particle size (1-100 nm), and low toxicity. Biological resources such as bacteria, algae, fungus, and plants have been used to manufacture affordable, energy-efficient, non-toxic, and ecologically acceptable metallic NPs. Despite the growing demand for Fe3O4 nanoparticles in a variety of applications, typical chemical production processes can produce hazardous byproducts and trash, resulting in significant environmental implications. The purpose of this study is to look at the ability of Allium sativum, a member of the Alliaceae family recognized for its culinary and medicinal benefits, to synthesize Fe3O4 NPs. Extracts of Allium sativum seeds and cloves include reducing sugars like glucose, which may be used as decreasing factors in the production of Fe3O4 NPs to reduce the requirement for hazardous chemicals and increase sustainability. The analytic procedures were carried out utilizing machine learning as support vector regression (SVR). Furthermore, because Allium sativum is widely accessible and biocompatible, it is a safe and cost-effective material for the manufacture of Fe3O4 NPs. Using the regression indices metrics of root mean square error (RMSE) and coefficient of determination (R2), the X-ray diffraction (XRD) study revealed the lighter, smoother spherical forms of NPs in the presence of aqueous garlic extract and 70.223 nm in its absence. The antifungal activity of Fe3O4 NPs against Candida albicans was investigated using a disc diffusion technique but exhibited no impact at doses of 200, 400, and 600 ppm. This characterization of the nanoparticles helps in understanding their physical properties and provides insights into their potential applications in landscape enhancement.

Assessment of Edaphic pollution indices and bioaccumulation of trace metals in Solanum lycopersicum, Spinacia oleracea and Triticum aestivum: an associated health risk evaluation

The present study investigates bioaccumulation factor (B_fc), Edaphic pollution indices and associated health risk assessment of trace metals (TMs) i.e., Cu, Fe, Zn, Mn and Co in the crops, agricultural soil (AgS), and irrigation water (IgW) collected from various peri-urban area of metropolitan city of India, Lucknow. Though the level of these TMs was within the permissible limits (PL) (FAO/WHO, 2011) in AgS and IgW however it was higher than PL in tomato, spinach and wheat cultivated in the fields. The bioaccumulation factor of Cu, Fe and Mn in edible parts of tomato, spinach and wheat was 8 to 25 times higher through the AgS and 10 to 300 times higher through the IgW in the tomato, spinach and wheat samples. The enrichment factor (E^fc), contamination factor (C^fc), contamination degree (C_dg) and modified contamination degree (mC_dg) values of Co, Cu, Mn, Fe and Zn ranged from low to high levels of contamination, whereas the geo-accumulation index reflected low contamination in agricultural soil. on the other hand, the metal pollution load index (M_pi) was found strongly contaminated in most of the study areas. Due to the consumption of these contaminated vegetables and cereal (VCs) by human consumers, the hazard quotient (HQ), total hazard quotient (THQ) and hazard index (HI) were found to be more than the requisite value of 1, which indicates a far-long health risk in this crowded city and its surrounding regions.

Intestinal response of Rana chensinensis larvae exposed to Cr and Pb, alone and in combination

Although numerous investigations on the adverse impact of Cr and Pb have been performed, studies on intestinal homeostasis in amphibians are limited. Here, single and combined effects of Cr (104 μg/L) and Pb (50 μg/L) on morphological and histological features, bacterial community, digestive enzymes activities, as well as transcriptomic profile of intestines in Rana chensinensis tadpoles were assessed. Significant decrease in the relative intestine length (intestine length/snout-to-vent length, IL/SVL) was observed after exposure to Pb and Cr/Pb mixture. Intestinal histology and digestive enzymes activities were altered in metal treatment groups. In addition, treatment groups showed significantly increased bacterial richness and diversity. Tadpoles in treatment groups were observed to have differential gut bacterial composition from controls, especially for the abundance of phylum Proteobacteria, Firmicutes, Verrucomicrobia, Actinobacteria, and Fusobacteria as well as genus Citrobacter, Anaerotruncus, Akkermansia, and Alpinimonas. Moreover, transcriptomic analysis showed that the transcript expression profiles of GPx and SOD isoforms responded differently to Cr and/or Pb exposure. Besides, transcriptional activation of pro-apoptotic and glycolysis-related genes, such as Bax, Apaf 1, Caspase 3, PK, PGK, TPI, and GPI were detected in all treatment groups but downregulation of Bcl2 in Pb and Cr/Pb mixture groups. Collectively, these results suggested that Cr and Pb exposure at environmental relevant concentration, alone and in combination, could disrupt intestinal homeostasis of R. chensinensis tadpoles.

Accumulation and human health risk assessment of trace elements in two fish species, Cirrhinus mrigala and Oreochromis niloticus, at Tarukri Drain, District Rahimyar Khan, Punjab, Pakistan

The toxic discharge of heavy metals into the water affects the aquatic ecosystem as well as the human population interacting with it because of their toxicity, bioaccumulation, long persistence, and transfer through the food chain. Thus, it is very important to conduct studies to determine the level of heavy metal pollution in order to better control, manage, and preserve the pollution of aquatic ecosystems. This study assessed heavy metal contamination in fish and its associated health risk to the population around the Tarukri Drain, Punjab, Pakistan. Two fish species (Oreochromis niloticus and Cirrhinus mrigala) were collected from three different sites in two different seasons. Collected fish were analyzed for cadmium (Cd), iron (Fe), lead (Pb), nickel (Ni), and zinc (Zn) accumulation using atomic absorption spectrometer (AAS). Furthermore, the human health risks associated with the consumption of affected fish were also assessed. Target hazardous quotient for seasonal consumers was between 0.12, - 1.58 × 10^-4, and 0.54 - 3.28 × 10^-4 (mg/kg) in O. niloticus and C. mrigala, respectively. While for regular consumers it was between 0.28-3.71 × 10^-4 and 1.27-7.68 × 10^-4 (mg/kg) in O. niloticus and C. mrigala respectively for the studied heavy metals. Fish sampled from Sadiqabad contained the highest concentration of heavy metals. The analysis of fish organs (kidney, liver, and muscles) showed heavy metal accumulation in the order of kidney > liver > muscles (p < 0.00). The obtained results showed that heavy metal contaminations in both fish species were within the permissible limits recommended by the World Health Organization (WHO). Both sampling seasons (i.e., summer and winter) showed a non-significant difference in heavy metal concentration. The calculated total target hazardous quotient across all heavy metals remained < 1 with only one exception. The carcinogenic risk assessment of heavy metals showed a non-significant effect in both fish species.

Fish liver damage related to the wastewater treatment plant effluents

Wastewater treatment plants (WWTPs) continuously release a complex mixture of municipal, hospital, industrial, and runoff chemicals into the aquatic environment. These contaminants are both legacy contaminants and emerging-concern contaminants, affecting all tissues in a fish body, particularly the liver. The fish liver is the principal detoxifying organ and effects of consistent pollutant exposure can be evident on its cellular and tissue level. The objective of this paper is thus to provide an in-depth analysis of the WWTP contaminants' impact on the fish liver structure, physiology, and metabolism. The paper also gives an overview of the fish liver biotransformation enzymes, antioxidant enzymes, and non-enzymatic antioxidants, their role in metabolizing xenobiotic compounds and coping with oxidative damage. Emphasis has been placed on highlighting the vulnerability of fish to xenobiotic compounds, and on biomonitoring of exposed fish, generally involving observation of biomarkers in caged or native fish. Furthermore, the paper systematically assesses the most common contaminants with the potential to affect fish liver tissue.

Contamination of Selected Toxic Elements in Integrated Chicken-Fish Farm Settings of Bangladesh and Associated Human Health Risk Assessments

The presence of trace elements in the environment can contaminate a food chain of an agro farm in various ways. Integrated chicken-fish farms (i.e., where poultry chicken and fish are cultivated in same places) are getting popular nowadays to meet the demands of a balanced diet. The present study conducted a health risk assessment on the basis of selected heavy metal (i.e., Cr and Pb) and metalloid (i.e., As) contamination in this type of farm in Bangladesh. Samples of various types were collected from different farms between September 2019 and March 2020. The concentrations of the elements were checked by Flame-AAS and HG-AAS. Our findings demonstrated that the elements' concentrations in fishes were simultaneously induced by the habitation and bioaccumulation through the food chain of the farm. The concentrations of As and Pb in the chicken parts and Cr and As in some fishes were greater than the highest limits set by different permissible standards. Overall, the metal concentration obtained in different samples was in descending order: sediment > droppings > different fish parts > various species of chicken > pond water. Among the pollutants, As gave target hazard quotient (THQ) values higher than 1 for all the species, suggesting health risks from the intake of fishes and chicken. However, there was non-target cancer risk present while considering all the elements together. Notably, the study found carcinogenic risks of As, Pb, and Cr for humans due to poultry and/or fish consumption; the identified health risks associated with the integrated farming setting will be crucial in further tackling strategies. Investigation of the possible sources of heavy metals in commercial chicken feeds and regular monitoring of groundwater used for agro-farming are highly recommended to reduce the burden.

Comparative assessment of human health risk associated with heavy metals bioaccumulation in fish species (Barbus grypus and Tenualosa ilisha) from the Karoon River, Iran: Elucidating the role of habitat and feeding habits

Concentrations of Cd, Ni, and Pb were measured in the liver and muscle tissues of benthic omnivorous (Barbus grypus) and pelagic herbivorous (Tenualosa ilisha) fish collected from two sampling sites along the Karoon River, Khuzestan Province, southwest of Iran. Potential human health risks were evaluated by measuring the estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI), and target cancer risk (TR). The results highlight the important role of habitat and feeding habits in the uptake of HMs by the two species. The EDI for all HMs exceeded the oral reference doses (RfDo) provided by the USEPA, indicating the two fish species are not entirely safe for human consumption. The THQ values were within the permissible limit (< 1), while HI values (> 1) showed there was non-carcinogenic risk for consumers. The TR values for Pb were within the acceptable range (1.00E-06-1.00E-04) for both species.

Assessment of groundwater geochemistry for drinking and irrigation suitability in Jaunpur district of Uttar Pradesh using GIS-based statistical inference

The quality of groundwater in the Jaunpur district of Uttar Pradesh is poorly studied despite the fact that it is the only supply of water for both drinking and irrigation and people use it without any pre-treatment. The evaluation of groundwater quality and suitability for drinking and irrigation is presented in this study. Groundwater samples were collected and analysed by standard neutralisation and atomic emission spectrophotometry for major anions (HCO₃^-, SO₄^2-, Cl^-, F^-, NO₃^-), cations (Ca²⁺, Mg²⁺, Na⁺, K⁺), and heavy metals (Cd, Mn, Zn, Cu, and Pb). The geographic information system (GIS) and statistical inferences were utilised for the spatial mapping of the groundwater's parameters. The potential water abstraction (i.e. taking water from sources such as rivers, streams, canals, and underground) for irrigation was assessed using the sodium absorption ratio (SAR), permeability index (PI), residual sodium carbonate (RSC), and Na percentage. According to the findings, the majority of the samples had higher EC, TDS, and TH levels, indicating that they should be avoided for drinking and irrigation. The positive correlation coefficient between chemical variability shows that the water chemistry of the studied region is influenced by geochemical and biological causes. According to the USSL (United States Salinity Laboratory) diagram, most of the samples fall under the C2-S1 and C3-S1 moderate to high salt categories. Some groundwater samples were classified as C4-S3 class which is unfit for irrigation and drinking. This study suggests that the groundwater in the study area is unfit for drinking without treatment. However, the majority of the samples were suitable for irrigation.

Metals bioaccumulation, possible sources and consumption risk assessment in five Sillaginid species, a case study: Bandar Abbas (Persian Gulf) and Chabahar Bay (Oman Sea), Iran

In this study, the concentrations of 10 metals (As, Al, Cd, Cr, Cu, Fe, Hg, Ni, Pb and Zn) in different tissues (gill, muscle and otolith) of five sillaginid species (Sillago arabica, S. attenuata and S. sihama from the Persian Gulf and S. indica, S. sihama and Sillaginopodys chondropus from the Oman Sea) were analyzed using ICP-MS, and the potential human health risk assessment for local consumers was also conducted using standard indices. The concentration of trace metals (μg g^-1 dw) in fish ranged from 0.24 to 16.09 (As), 7.88 to 167.51 (Al), 0.005 > -0.866 (Cd), 0.006 > -7.95 (Cr), 1.02-5.58 (Cu), 24.86 to 390.85 (Fe), 0.005 > -1.93 (Hg), 0.021 > -7.80 (Ni), 0.33-4.41 (Pb) and 4.78-170.43 (Zn). The levels of trace metals varied significantly among sampling sites, fish species and their tissues. Gill tissues accumulate higher concentrations of the analyzed elements, except for As and Hg, whose higher concentrations were found in muscle tissues. Among the species, S. sihama in the Persian Gulf showed the highest levels of toxic metals compared to the other species. The dendrogram of metal association in fish muscle tissues revealed that Ni, Cr, Cd, Pb and Hg in muscles mainly originated from anthropogenic sources, especially petroleum activities. A second dendrogram based on the association of these five metals in the muscle tissue separated the sillaginid species of the Persian Gulf from the Oman Sea. The mean concentrations of the analyzed metals in the edible tissues were lower than international standards of maximum permissible limits (MPL), except for inorganic As (_iAs) and Pb. The index of estimated daily intake (EDI) for Cr and Hg in all sillaginid species, and _iAs, Pb and Ni only in the Persian Gulf's sillaginid species was higher than the recommended values. The value of the target hazard quotient (THQ) indicated that the intake of individual heavy metals due to the consumption of sillaginid species was safe for human health (except Hg in S. arabica) whereas combined heavy metals' intake revealed potential health problems in the case of increased consumption for all three sillaginids in the Persian Gulf. Target cancer risk (TR) for _iAs in all species and Cd, Cr and Ni in Persian Gulf species was higher than the acceptable range. The results indicated the health issues associated with high consumption, especially for sillaginids in the Persian Gulf, which should be considered in food safety monitoring for local people in the area.

Bioaccumulation and human health risk assessment of some heavy metals in sediments, Sparus aurata and Salicornia europaea in Güllük Lagoon, the south of Aegean Sea

In the current study, it was aimed to determine the sediment in Sparus aurata (Linnaeus 1758) tissues and Salicornia europaea L. Cu, Zn Fe, Hg, Cd, Pb and Mn concentration distributions in Güllük Lagoon which is located in the south of Aegean Sea and under the influence of anthropogenic activities by means of metal pollution and health indices and to investigate the effects of these metals on public health. The concentration range of Cu, Zn, Fe, Hg, Cd, Pb and Mn in sediment samples was determined as 12.16-26.00, 1.62-2.03, 7.77-8.36, 7.52-16.15, 0.071-0.40, 7.99-13.74 and 12.11-12.63 mg kg^-1, respectively. Cu and Hg concentrations in sediment were found to be higher than sediment quality guidelines standards. In addition, according to the enrichment factor (EF), Hg, Cd and Cu were found to show above moderate enrichment. Cu, Zn, Fe, Hg, Cd and Mn concentrations in S. aurata muscle tissue were 1.31 ± 2.30, 1.01 ± 0.24, 3.43 ± 0.75, 2.79 ± 0.85, 0.01 ± 0.01 and 1.80 ± 1.12 mg kg^-1, respectively. S. europaea heavy metals (HMs) concentrations were determined as Cu = 10.97 ± 3.20, Zn = 0.74 ± 0.62, Fe = 5.69 ± 0.22, Hg = 9.62 ± 8.84, Cd = 0.53 ± 0.33, Pb = 0.22 ± 0.26 and Mn = 8.61 ± 0.14 mg kg^-1. It was seen that Hg in S. aurata muscle tissue and Hg in S. europaea concentrations exceeded the limit values determined for consumption purposes. Target hazard quotient (THQ) and total target hazard quotient (TTHQ) values were found to be < 1 for S. aurata and S. europaea. When all these results were considered, it was determined that the metals that could pose a potential ecological and health risk were Hg, Cd and Cu in the study area.