Occurrence and seasonal variations of heavy metal (loid)s in lake case: effects of climate and water source perspectives

Following recent concerns of chemical pollution around Lake Naivasha, especially originating from recent agricultural activities in the catchment, samples of water, sediments, and fish Common carp (Cyprinus carpio) were collected from the Hippo Point, Kasarani, Mouth of Malewa River, Mouth of Karati River, Crescent Island, Sher Karuturi Discharge outlet and Oserian Bay for analysis of Cu, Cd and Pb by FAAS. The mean heavy metal levels ranged from 5.12–58.11 (Pb), 1.06–1.73 (Cd), and <0.03–2.29 (Cu) mg/kg wet weight in C. carpio muscle, <100–179.83 (Pb), <10.00–10.06 (Cd) and <30.00–32.33 (Cu) μg/L in surface water, and 17.11–53.07 (Pb), 1.18–5.58 (Cd) and 3.00–8.48 (Cu) mg/kg dry weight in sediment and showed a wide variation within and between samples with relatively high concentrations in sediments and fish muscle tissues. The results indicate that Lake Naivasha, in some parts, is polluted with these heavy metals of which relatively higher concentrations are found at the discharge outlets near Sher Karuturi and Oserian Bay. This indicates possible contribution from surrounding horticultural/floricultural activities and the Mouths of the Rivers Malewa and Karati which flow from it’s upper catchment.

ABSTRACTImproper disposal of domestic sewage and effluents from drug manufacturing units for several years has resulted in the accumulation of pollutants in Musi river sediments. There were no studies carried out before to quantify the antibiotic resistance in this river, despite the fact that its sediments are loaded with antibiotics. The present study investigated the relationship between the proliferation of ciprofloxacin resistant culture with the occurrence of fluoroquinolone and heavy metals in sediments of Musi River. The fluoroquinolones concentration in river sediments were observed in high concentration (13336.4 ng/g) and were found to be positively correlated with the occurrence of ciprofloxacin resistant bacteria (r = 0.386 to 0.675, p < 0.05). The occurrence of heavy metals was also in positive correlation with the distribution of antibiotic resistant bacteria in the river (r = 0.454 to 0.881, p < 0.05). This study indicated the spread of antibiotic resistance in polluted river sediments that might pose a serious threat to public health as the river water is used for irrigation, drinking, and recreational purposes; and needs an immediate risk assessment and mitigation strategies.

Background: Aquatic ecosystems face an increase of contamination from heavy metals released through urban waste, agricultural runoff and industrial effluents. Such toxic elements, that are non-biodegradable, accumulate in aquatic organisms and persist in the environment, leading to various behavioral and physiological disturbances. Between freshwater species, common carp (Cyprinus carpio) aids as a best bio indicator because of its sensitivity to pollutants and wide distribution. Heavy metals for example mercury (Hg), copper (Cu), cadmium (Cd), chromium (Cr), and lead (Pb) are mainly recognized to induce oxidative stress that damages tissues and organs of fish at cellular and biochemical levels. Purpose: The aim of this review is to analyze and summarize present research on the effects of heavy metal exposure on behavioral changes, hematological changes and oxidative stress in carp fish. Its focus is to understand how such pollutants influence the normal behavioral patterns of fish, change antioxidant enzyme activity and induce hematological changes that contribute to reduced ecological fitness and physiological impairments. Materials and Methods: Related data were composed from scientific databases that include PubMed, Springer Link, Science Direct and Google Scholar. Readings associated to oxidative biomarkers, heavy metal exposure and behavioral parameters in carp fish (Cyprinus carpio) were studied. Some keywords such as “oxidative stress,” “behavioral changes,” “hematological changes”, “heavy metals,” “aquatic toxicity” and “carp fish,” were used. Comparative study of results from numerous studies was accomplished to highlight consistent variations and patterns through experimental situations. Results: Findings shown that heavy metals raise reactive oxygen species (ROS) levels that lead to oxidative stress as well as depletion of antioxidant enzymes for example catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD). Such biochemical disproportions are frequently accompanied by behavioral abnormalities for example reduced swimming performance, decreased feeding activity, loss of equilibrium and erratic movements, all are symbolic of stress as well as neurotoxicity. Conclusion: The exposure of heavy metal considerably affects the behavioral, hematological and oxidative physiology of carp fish that compromise their total health, survival and growth. The understandings of such responses offer valuable perception for ecological risk assessment and environmental monitoring. The review highlights the significance of using behavioral biomarkers and antioxidant as sensitive indicators for identifying heavy metal pollution in aquatic environments and inspires stricter pollution control approaches to shield aquatic biodiversity.

Heavy metals are potentially toxic to organisms causing lethal and sub lethal effects. Above threshold levels, these metals have been shown to adversely affect both aquatic and terrestrial organisms. Human health may also be impacted negatively through consumption of metal-contaminated foods and water. Lake Naivasha, Kenya, like many freshwater bodies in developing countries is a source of fish and water for human consumption in Naivasha town and its environs. Ironically, the lake receives untreated floricultural, agricultural and industrial effluents from its catchment area. In the recent past, there have been unconfirmed reports that fish from this lake are contaminated with heavy metals mainly Cu, Hg, Cd and Pb to levels that are harmful to humans. It is against this background that this study was conducted to determine the sources of the aforementioned heavy metals in the lake, their concentrations in water and sediments and in common carp (<em>Cyprinus carpio</em>) that constitutes a major portion of the Lake Naivasha fishery. Water, sediment and fish samples were collected from purposefully selected sites in six sampling occasions during both the dry and wet seasons. Analyses for heavy metals in fish, sediment and water samples were done using an Atomic Absorption Spectrophotometer (AAS). The study findings indicate that the heavy metal concentrations in the water and sediments collected from impacted sites were significantly higher (p<0.05) compared to those from unexpected sites. In spite of this, the metal concentrations in water were significantly lower than those recommended by the WHO and USEPA as drinking water guideline values. Metal concentrations in <em>C. carpio</em> were also significantly lower (p<0.05) than the World Health Organization (WHO) recommended levels for fish intended for human consumption. Based on these findings, it is safe to conclude that drinking water and fish collected from Lake Naivasha do not pose immediate health risks to human health. Despite this observation, we recommend continuous monitoring of heavy metal concentrations in water and sediment in the lake given their potential for bioaccumulation and biomagnifications and likely adverse effects on aquatic organisms and humans.

In this study, a sample of 220 common carp (Cyprinus carpio Linnaeus 1758) was obtained from two distinct ponds in the Taqtaq District, situated in the northeastern region of Erbil Province, Kurdistan Region, Iraq. Specifically, 98 specimens were sourced from Pond A, while 122 were collected from Pond B., between September 2021 and April 2022. The fish underwent examination to determine the presence of fungal infections. The study identified eight species of fungi through morphological analysis of colony characteristics, specific growth media, and the VITEK II compact system (Biomerieux-USA). This research marks the initial documentation of five fungal species (Aspergillus flavus, Naganishia albidus, Penicillium vermiculatus, Cystobasidium minutum, and Sporothrix schenckii) infecting common carp in Iraq. Additionally, three fungal species (Aspergillus fumigatus, Aspergillus niger, and Saprolegnia parasitica) were reported for the first time in common carp within the Kurdistan Region.

The occurrence of heavy metals (HMs) in drinking water has been a critical water quality concern for a long time and can compromise its aesthetic value to the larger extent. Chronic exposure of human beings to these toxic and non-toxic HMs through water ingestion can result in significant health risks. To assess these associated health risks, the present study was planned, designed and carried out for analyses of nine HMs namely, Al, Cr, Mn, Co, Ni, Cu, Zn, Cd and Pb in the potable water samples collected from different sources located across the Mandakini valley of Garhwal Himalaya, India using Inductively Coupled Plasma Mass Spectrometry. The measured values of Al, Cr, Mn, Co, Ni, Cu, Zn, Cd and Pb were found in the range of BDL–27.4 µg l−1, 0.26–4.5 µg l−1, BDL–139 µg l−1, 0.02–0.9 µg l−1, 0.4–5.5 µg l−1, 0.07–9.2 µg l−1, BDL–4164 µg l−1, BDL–0.8 µg l−1, and BDL–11.2 µg l−1, respectively. The observed values of analyzed HMs except Zn and Pb were found below the reference values prescribed by the WHO, USEPA and BIS. In addition, Zn concentration exceeded its maximum permissible limit (4000 µg l−1) recommended by WHO for infants at one station only. The observed indices show that there are no health risks from HMs contamination via drinking water in the region. Moreover, the estimated hazard quotients for children and adults also revealed no potential health risks. The results of present study will be useful as baseline data for state and national regulatory agencies.

The study assessed the occurrence of legally-monitored heavy metals and unmonitored antimicrobials in sludge from small, medium, large and very large municipal wastewater treatment plants (WWTPs), and the predicted environmental risk and risk of resistance selection associated with sludge administration to soil. The temporal variations of the studied compounds in sludge and associated risks to soil were determined by sampling over a year.Although the highest concentrations of heavy metals were noted in sludge from the largest WWTP, i.e. from 1.50 mg/kg (mean 1.61 mg/kg) for Cd to 2188 mg/kg (mean 1332 mg/kg) for Zn, the obtained values only reached a few percent of the legal limits. The same WWTP also demonstrated lower concentrations of antimicrobials compared to the smaller ones. The highest concentrations of antimicrobials, ranging from 24.04 μg/kg for trimethoprim to 900.24 μg/kg for tetracycline, were found in the small and medium WWTPs. However, due to lack of regulations at the national and EU levels, the results cannot be compared with legal limits. Principal Component Analysis (PCA), cluster and heatmap analysis separated samples according to WWTP size. Small WWTP demonstrated correlation with antimicrobials (tetracycline, trimethoprim, clindamycin, ciprofloxacin and ofloxacin), while the large and very large WWTP revealed correlations with heavy metals (Cu and Cr).The obtained environmental risk quotients confirmed that the heavy metals did not present a threat, measured either as individual risk quotients (RQenv), cumulative risk (RQcumulative) or risk of mixture of heavy metals (RQmix-metals). In the case of antimicrobials, only tetracycline demonstrated moderate RQenv, RQcumulative and RQmix-antimicrobials in the small WWTP sludge, with values of 0.1 to 1. Our findings highlight the importance of monitoring sewage sludge before soil application, especially from small WWTPs, to reduce the potential environmental impact of antimicrobials. They also confirm our previous data regarding the environmental risk associated with various toxic compounds, including emerging contaminants, in the sludge from small WWTPs.

Potential metal phytoremediation in peri-urban wetlands using rooted macrophytes

Swimming, grazing and social behaviour of rohu Labeo rohita (Hamilton) and common carp Cyprinus carpio (L.) in tanks under fed and non-fed conditions

Rapid urbanization and industrialization in communities of Nigeria contribute significantly to environmental pollution. Amongst the diversity of these environmental contaminants are heavy metals, a rarely biodegradable and toxic class of metals. Heavy metals are known to be harmful to plants, aquatic species, and subsequently endanger human health through bioaccumulation or biomagnification. Even at low concentrations, heavy metals may affect key soil microbial processes; inhibit plant metabolism and growth. Toxic metals in groundwater affect water quality and potability, and their presence in aquatic systems also facilitate the production of reactive oxygen species that can damage physiological processes in fishes and other aquatic organisms. This chapter highlights the occurrence and impact of heavy metals in different environmental matrices and organisms sampled across some Southwestern states in Nigeria. Various studies including those of the authors found varying levels of heavy metals, especially in concentrations that can imperil ecosystem functions. While results of studies included in this chapter may suggest heavy metal introduction through anthropogenic-urbanization means, the lack of proper implementation of environmental monitoring laws in Nigeria also clearly exist. As such, the mitigation of heavy metals amongst other pollutants demands better home-grown decentralized technologies.

Heavy metal concentrations in sediments and Cyprinus carpio from Maqalika Reservoir –Maseru, Lesotho: An analysis of potential health risks to Fish consumers

Background.Efforts are needed to evaluate heavy metal concentrations in aquatic sediments which serve as repositories and as sources of contamination of other habitats.Objectives.The present study assessed temporal changes in the pH, particle size and concentration of metals in sediments of a mining-affected river in Zambales, Philippines.Methods.Sediment samples were collected at different periods in four stations along the river using a modified Van Veen grab. The samples were subjected to quartering, air-drying, and sieved through a mesh of 40 mm prior to X-ray fluorescence spectroscopy analysis using Thermo Scientific Niton XL3t to determine metal concentrations. The sediment particle size was analyzed by the sieve method and soil pH by the electrode method.Results.Measured metal concentrations in the sediment were as follows: iron (Fe)> calcium (Ca)> chromium (Cr)> nickel (Ni)> manganese (Mn) with averages of 174.6 mg/g, 7.89 mg/g, 6.54 mg/g, 4.82 mg/g, and 2.75 mg/g dry matter (DM), respectively. The mean pH of riverine sediments was generally neutral, except for Station 4. In terms of particle size, silt and clay fractions increased in the upstream station but decreased in the midstream and downstream stations across the sampling periods. The flooding brought by Typhoon Koppu resulted in lowered concentrations of Fe, Mn, Cr, and Ni and an upsurge in Ca and potassium levels.Discussion.Most of the heavy metals (Fe, Ni, Cr, Mn) exceeded the probable effect level (PEL) for inorganics in sediments, suggesting that the adverse effects of these metals on the environment and aquatic organisms are expected to occur frequently. In comparison with Station 4, which was less affected by siltation, there was a sign of metal enrichment in the area. This indicates that soil erosion and runoff, which might have been triggered by vegetation loss, mineral extraction, and agricultural activities, had a significant impact on the quality of river sediments.Conclusions.The findings of the study point to the need for the formulation and implementation of appropriate regulatory measures for the protection and rehabilitation of the heavy metal-loaded river.Competing Interests.The authors declare no competing financial interests.

Improper disposal of domestic sewage and effluents from drug manufacturing units for several years has resulted in the accumulation of pollutants in Musi river sediments. There were no studies carried out before to quantify the antibiotic resistance in this river, despite the fact that its sediments are loaded with antibiotics. The present study investigated the relationship between the proliferation of ciprofloxacin resistant culture with the occurrence of fluoroquinolone and heavy metals in sediments of Musi River. The fluoroquinolones concentration in river sediments were observed in high concentration (13336.4 ng/g) and were found to be positively correlated with the occurrence of ciprofloxacin resistant bacteria (r = 0.386 to 0.675, p<0.05). The occurrence of heavy metals was also in positive correlation with the distribution of antibiotic resistant bacteria in the river (r = 0.454 to 0.881, p<0.05). This study indicated the spread of antibiotic resistance in polluted river sediments which might pose a serious threat to public health as the river water is used for irrigation, drinking, and recreational purposes; and needs an immediate risk assessment and mitigation strategies.

Concentrations of heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn) were measured in water, sediments, Ceratophyllum (hornwort), and Bellamya sp. (edible snail) from residential, mixed (industrial and commercial), and agricultural areas with rural rivers in the Taihu Lake region, China. Zn concentrations were the highest, whereas Cd concentrations were the lowest among the six metals in water, sediments, and aquatic organisms. Cd was mainly present in the acid-soluble fraction, Cr in the residual fraction, and Pb in the reducible fraction of sediments. Heavy metal concentrations in water, sediments, and aquatic organisms in the three areas followed the order of the mixed area > residential area > agricultural area. Heavy metal concentrations in aquatic organisms were not only related to total metal concentrations in water and sediments but also to metal speciation concentrations in sediments. In addition, the bio-concentration factor (BCF) values of Cr, Cu, Pb, and Zn for Bellamya sp. were higher than those for Ceratophyllum, whereas the BCF values of Cd and Ni for Bellamya sp. were lower than those for Ceratophyllum. An ecological risk assessment of heavy metals in sediments showed that Cd posed the highest ecological risk to the environment. A health risk assessment showed that consuming Bellamya sp. from the mixed area could cause a potential health risk.

The occurrence of heavy metals in water ecosystems and sediment can impact human life, due to their possible transfer to food chain and adverse effects. Therefore, it is crucial the evaluation of the status of heavy metals in water and sediments in order to evaluate water quality and their environmental impacts. Current study aims to evaluate the occurrence of heavy metals in water and sediment as well as the water and sediment pollution of Drini Bardhe River in Kosovo. Three representatives sampling sites were selected along Drini Bardhe River to collect water and sediment samples. Heavy metals concentrations in water and sediment samples were determined by using atomic absorption spectrophotometer (AAS). The data of heavy metal concentration in water were compared with EC Directives 75/440/EEC and 2008/105/EC in order to evaluate water quality. The degree of sediment pollution was evaluated by using Enrichment Factor (EF) and Geo-accumulation Index (Igeo). Based on obtained data of heavy metals concentration in water, the values of iron and arsenic were over acceptable values of EC directives. Enrichment factor (Ef) calculations showed that sediments have moderate severe enrichment for Cd and Ni, minimal enrichment for Cu, Cr, and Pb, whereas no enrichment for Fe, Mn and Zn. Based on Geo-accumulation Index (Igeo) calculations sediments result strongly polluted with Cd and Ni, moderately polluted with Cr, unpolluted to moderately polluted with Cu, Mn, Pb and Zn, and unpolluted with Fe. The Occurrence of heavy metals in water and sediments indicates potential risk of some heavy metals as their amounts were over acceptable limits. Keywords: Heavy metals, Ef, Igeo, pollution, water, sediment.