Advances in the Effect of Heavy Metals in Aquatic Environment on the Health Risks for Bone

The increasing levels of toxic heavy metals in aquatic environments pose significant threats to ecosystems, biodiversity, and human health. The Diva-Motagaon Creek, located in Thane District, Mumbai, is one such site under investigation in this study, which aims to analyze the concentrations of various toxic heavy metals in sediment samples. As a reliable and accurate method, Atomic Absorption Spectroscopy (AAS) was used to study the effects of long-term pollution load and the buildup of heavy metal contaminants in this estuarine ecosystem.Sediment samples were collected from four strategically selected stations along the Diva-Motagaon Creek, covering four seasons from January 2023 to December 2023. The four seasons—pre-monsoon, monsoon, post-monsoon, and summer—were chosen to capture the seasonal variations in pollution levels, as aquatic environments are highly dynamic and pollutant concentrations can fluctuate due to factors like rainfall, industrial runoff, and human activities. The collected samples were analysed for the presence of chromium (Cr), copper (Cu), iron (Fe), lead (Pb), and zinc (Zn), which are commonly found in environmental pollution, particularly industrial effluents, urban runoff, and agricultural practices.The analysis revealed notable variations in the concentrations of these heavy metals across different seasons and geographical locations within the creek. Zinc was found to be the most abundant heavy metal, followed by iron, copper, lead, and chromium, in that order. The fact that the concentration changes with the seasons suggests that the metal levels are affected by things like industrial discharges, monsoon runoff, and human activities in the area, such as religious events like immersing Ganapati idols. Among the studied metals, zinc showed the highest concentrations, which may be attributed to local industrial activities and sewage discharge into the creek.The results of this study demonstrate that heavy metal pollution in Diva-Motagaon Creek is influenced by a combination of natural processes and anthropogenic activities. High levels of metals like lead, copper, and chromium are especially bad for the environment because they can build up in aquatic organisms and make fish, invertebrates, and other marine life sick. Zinc, while essential in trace amounts for aquatic organisms, can become toxic in higher concentrations, disrupting the health of aquatic ecosystems.The study’s findings are crucial for environmental management and policy development, as they offer a scientific basis for monitoring and controlling pollution in the Diva-Motagaon Creek. The findings indicate the need for immediate action to reduce the heavy metal concentrations in the creek, particularly through effective waste management practices, industrial regulation, and pollution control strategies. The fishing industry is prevalent in the area, and the study's results emphasise the importance of protecting aquatic resources to ensure the safety of local livelihoods and the sustainability of the marine ecosystem.This study sets a baseline for the current level of pollution, which is very important for future research and actions that will be taken to help the environment and lessen the harmful effects of heavy metal pollution. The results can inform the rational planning of pollution control strategies and support efforts to restore and protect the health of Diva-Motagaon Creek. The results also show how important it is for scientists to keep an eye on things all the time to learn more about how heavy metal toxicity changes over time and how it affects marine and estuarine environments over time.The increasing levels of toxic heavy metals in aquatic environments threaten ecosystems, biodiversity, and human health. Atomic Absorption Spectroscopy (AAS) is used to look at heavy metal contamination in sediment samples from Diva-Motagaon Creek in Thane District, Mumbai. In 2023, samples were taken from four locations during four seasons: pre-monsoon, monsoon, post-monsoon, and summer. The goal was to see how the concentrations of chromium (Cr), copper (Cu), iron (Fe), lead (Pb), and zinc (Zn) changed with the seasons.Results revealed significant seasonal and spatial variations, with zinc being the most abundant metal, followed by iron, copper, lead, and chromium. High metal levels, especially during and after the monsoon season, are a sign of pollution from factories, urban runoff, and human activities like immersing Ganapati idols. While zinc is essential in trace amounts, its high concentrations, along with toxic levels of lead, copper, and chromium, pose ecological risks through bioaccumulation in aquatic organisms.These findings highlight the urgent need for pollution control measures, including industrial regulation, improved waste management, and continuous environmental monitoring. Given the creek’s significance to local fisheries, mitigating heavy metal contamination is crucial for preserving marine ecosystems and safeguarding livelihoods. This study establishes a baseline for future research and policy interventions to restore and protect Diva-Motagaon Creek.

Microalgae account for most of the biologically sequestered trace metals in aquatic environments. Their ability to adsorb and metabolize trace metals is associated with their large surface:volume ratios, the presence of high-affinity, metal-binding groups on their cell surfaces, and efficient metal uptake and storage systems. Microalgae may bind up to 10% of their biomass as metals. In addition to essential trace metals required for metabolism, microalgae can efficiently sequester toxic heavy metals. Toxic heavy metals often compete with essential trace metals for binding to and uptake into cells. Recently, transgenic approaches have been developed to further enhance the heavy metal specificity and binding capacity of microalgae with the objective of using these microalgae for the treatment of heavy metal contaminated wastewaters and sediments. These transgenic strategies have included the over expression of enzymes whose metabolic products ameliorate the effects of heavy metal-induced stress, and the expression of high-affinity, heavy metal binding proteins on the surface and in the cytoplasm of transgenic cells. The most effective strategies have substantially reduced the toxicity of heavy metals allowing transgenic cells to grow at wild-type rates in the presence of lethal concentrations of heavy metals. In addition, the metal binding capacity of transgenic algae has been increased five-fold relative to wild-type cells. Recently, fluorescent heavy metal biosensors have been developed for expression in transgenic Chlamydomonas. These fluorescent biosensor strains can be used for the detection and quantification of bioavailable heavy metals in aquatic environments. The use of transgenic microalgae to monitor and remediate heavy metals in aquatic environments is not without risk, however. Strategies to prevent the release of live microalgae having enhanced metal binding properties are described.

Microplastics as a vehicle of heavy metals in aquatic environments: A review of adsorption factors, mechanisms, and biological effects

Sediment plays animportant role in controlling biogeochemical cycling of heavy metals in aquatic environment. The Ya-Er Lake is a typical lake which was historically contaminated by heavy metals in Hubei province, China. After industries surrounding the Ya-Er Lake being shut down, oxidation pond treatment and dredging program were conducted for pollution management since 1970s. To date, the Ya-Er Lake has been used for aquaculture for several decades. However, the status of heavy metal levels and ecological risks in this lake remains unclear. Herein, concentrations, chemical fractions, and risk assessment of heavy metals were investigated in the Ya-Er Lake sediment. Results showed that concentrations of heavy metals in the Ya-Er Lake sediment were higher than other reported lake systems, suggesting that heavy metal pollution in the Ya-Er Lake is still serious. Relatively higher proportions of carbonates bound form of Cd and Ni indicated high-risk potential of these two heavy metals, and Cd and Ni should be listed as the primary heavy metal pollutants in the Ya-Er Lake according to the results of potential ecological risk index (PERI) and sediment quality guidelines (SQGs). The risk assessment code (RAC) analysis showed that Ni and Cd poses higher bioavailability and mitigation potential, and may affect the Ya-Er Lake ecosystem and downstream aquatic environment. These findings reflected that oxidation pond treatment and dredging sediment to near place are not effective to control heavy metal pollution, and a long-term ecological risk is still posed to surrounding aquatic environment. Our study provides scientific basis on pollution control and management in aquatic system contaminated by heavy metals.

Heavy metals are among the most persistent and hazardous pollutants affecting aquatic ecosystems worldwide. Their presence in water bodies is influenced by both natural processes and anthropogenic activities such as industrial discharge, agricultural runoff, mining, and urbanization. Seasonal variations significantly affect the concentration, distribution, and chemical behavior of heavy metals in aquatic environments by altering hydrological conditions, physicochemical parameters, and biological activity. These seasonal dynamics directly influence the bioavailability of metals and their subsequent uptake by aquatic organisms, particularly fish. Fish accumulate heavy metals in various tissues through direct absorption from water and through dietary intake, leading to seasonal variations in bioaccumulation patterns. Elevated temperatures and increased metabolic activity during warmer seasons often enhance metal uptake, while colder seasons may reduce accumulation rates. Seasonal bioaccumulation of heavy metals poses serious ecological risks to aquatic life and potential health hazards to humans through fish consumption. This theoretical review highlights the seasonal dynamics of heavy metals in aquatic environments and their bioaccumulation in fish tissues, emphasizing the importance of seasonal monitoring for environmental management and public health protection.

Microplastics (MPs) migrate by adsorbing heavy metals in aquatic environments and act as their carriers. However, the aging mechanisms of MPs in the environment and the interactions between MPs and heavy metals in aquatic environments require further study. In this study, two kinds of materials, polyamide (PA) and polylactic acid (PLA) were used as target MPs, and the effects of UV irradiation on the physical and chemical properties of the MPs and the adsorption behavior of Cu(II) were investigated. The results showed that after UV irradiation, pits, folds and pores appeared on the surface of aged MPs, the specific surface area (SSA) increased, the content of oxygen-containing functional groups increased, and the crystallinity decreased. These changes enhanced the adsorption capacity of aged MPs for Cu(II) pollutants. The adsorption behavior of the PA and PLA MPs for Cu(II) conformed to the pseudo-second-order model and Langmuir isotherm model, indicating that the monolayer chemical adsorption was dominant. The maximum amounts of aged PA and PLA reached 1.415 and 1.398 mg/g, respectively, which were 1.59 and 1.76 times of virgin MPs, respectively. The effects of pH and salinity on the adsorption of Cu(II) by the MPs were significant. Moreover, factors such as pH, salinity and dosage had significant effects on the adsorption of Cu(II) by MPs. Oxidative complexation between the oxygen-containing groups of the MPs and Cu(II) is an important adsorption mechanism. These findings reveal that the UV irradiation aging of MPs can enhance the adsorption of Cu(II) and increase their role as pollutant carriers, which is crucial for assessing the ecological risk of MPs and heavy metals coexisting in aquatic environments.

The mobility of heavy metals in aquatic environments, impacted by discharges from mining waste, is one of the major processes causing metal pollution mainly by arsenic (As), cadmium (Cd), lead (Pb), zinc (Zn) and iron (Fe), which could be risky for biota and human health. The heavy metals contained in mining waste constituted by large amounts of sulfides can reach the aquatic compartments by acid mine drainage and runoff and eventually become deposited in sediments and associated with colloidal material, being this one of the main reservoirs and ways of transport. However, the mobility of heavy metal is influenced by their specific chemical properties and undergo several physicochemical phenomena as sorption, oxidation–reduction, hydrolysis and this can be influenced by water flow, the size and composition of geological material. Hence, this work aims to review the processes and mechanism involved in the fate and transport of heavy metals from mining-waste to aquatic compartments and the methods used for identification of the specific chemical species associated with their mobility and ecological risk.

Higher levels of heavy metals in aquatic environments are most likely influenced by crude oil spills which may induce significant risk of heavy metal toxicity in aquatic species and humans. This research evaluated the levels of heavy metals and other physicochemical parameters in the crude oil-impacted Santa-Barbara River and environs of Bayelsa State, Nigeria. Heavy metals and other physicochemical parameters were examined using standard methods. Heavy metal pollution status was then deduced with standard pollution indicators. The water and fish samples collected from crude oil-impacted Santa Barbara River were heavily and moderately contaminated with iron, respectively (Igeo index = 4.29 and 2.87 for water and fish, respectively) and highly polluted with examined heavy metals (PLI = 4.29 and 1.13 for water and fish, respectively). The water samples from hand-dug wells were moderately contaminated with iron (Igeo index = 2.87) with overall low pollution by heavy metals (PLI = 0.46), while fish sold in neighboring communities was moderately contaminated with iron (Igeo index = 2.98) with overall moderate pollution by heavy metals (PLI = 0.86). However, potential ecological risks mediated by examining heavy metals in all water and fish samples were generally low (RI < 40). The total dissolved solids, biochemical oxygen demand, nitrate and phosphate concentrations in all water samples were within permissible limits of WHO and FEPA. The ecological risks associated with water and fish from all sampling locations were deduced as low, mainly because iron was the most abundant heavy metal contaminant with no significant toxic response.

As the most important graphene derivate, graphene oxide (GO) is a high-efficient adsorbent for the removal of heavy metals in aquatic environment due to its abundant oxygen functional groups, enormous specific area, and strong hydrophilia. However, there are some drawbacks, such as easily aggregating and difficult separation, restricting the environmental application of GO. GO is not a suitable adsorbent by itself. Hence, some materials were used to synthesize GO composites, and GO composites are commonly characterized by high adsorption capacity to overcome the above drawbacks. This review discusses five main GO composites-GO-chitosan, GO-alginate, GO-SiO2, NZVI-rGO, and magnetic GO composites-and summarizes the synthesis methods of GO composites and its application for the removal of heavy metals in aquatic environments. The influencing factors, adsorption capacities, and mechanisms related to the removal of heavy metals by GO composites are highlighted. Lastly, the application potentials and challenges of GO composites for aqueous environmental remediation are discussed. Graphical abstract.

Water-sediment interactions and mobility of heavy metals in aquatic environments

Water quality degradation due to heavy metal contamination poses serious threats to both human health and aquatic ecosystems. The rise in the concentration of heavy metals in aquatic environments is largely attributable to anthropogenic activities. These metals accumulate over time in water bodies, necessitating rigorous monitoring to accurately assess pollution levels. The present study is concerned with the assessment of heavy metal pollution in the Styr River (Ukraine) before and after the discharge of water from a nuclear power plant. The assessment is based on three indices: the Heavy Metal Pollution Index, the Heavy Metal Evaluation Index, and the Degree of Contamination. Therefore, heavy metals, including zinc (Zn), cadmium (Cd), lead (Pb), copper (Cu), nickel (Ni), manganese (Mn), arsenic (As) and chromium (Cr), were analyzed in this study. Water samples were collected at two locations on a monthly basis over the course of five years (2018–2022) and subsequently analysed using inductively coupled plasma optical emission spectroscopy. The results indicates a low contamination level at both sampling sites, indicating stable and uniform concentrations of metals across the study area. Moreover, statistical analysis highlights significant associations between certain metals and pollution indices, supporting the indices’ utility in tracking pollution trends and assessing environmental impacts. This dataset underscores the importance of ongoing monitoring for effective water quality management.

The waterborne Vibrio parahaemolyticus can cause acute gastroenteritis, wound infection, and septicemia in humans. Pollution of heavy metals in aquatic environments is proposed to link high incidence of the multidrug-resistant (MDR) pathogen. Nevertheless, the genome evolution and heavy metal tolerance mechanism of V. parahaemolyticus in aquatic animals remain to be largely unveiled. Here, we overcome the limitation by characterizing an MDR V. parahaemolyticus N10-18 isolate with high cadmium (Cd) tolerance using genomic and transcriptomic techniques. The draft genome sequence (4,910,080 bp) of V. parahaemolyticus N10-18 recovered from Ostrea gigas Thunberg was determined, and 722 of 4653 predicted genes had unknown function. Comparative genomic analysis revealed mobile genetic elements (n = 11) and heavy metal and antibiotic-resistance genes (n = 38 and 7). The bacterium significantly changed cell membrane structure to resist the Cd2+ (50 μg/mL) stress (p < 0.05). Comparative transcriptomic analysis revealed seven significantly altered metabolic pathways elicited by the stress. The zinc/Cd/mercury/lead transportation and efflux and the zinc ATP-binding cassette (ABC) transportation were greatly enhanced; metal and iron ABC transportation and thiamine metabolism were also up-regulated; conversely, propanoate metabolism and ribose and maltose ABC transportation were inhibited (p < 0.05). The results of this study demonstrate multiple strategies for the Cd tolerance in V. parahaemolyticus.

Bioindication of heavy metals in aquatic environment using photosynthetic pigments in cyanobacteria

The pollution of heavy metals in aquatic environments is a major concern for human beings. The present study demonstrates the phytoremediation potential of the aquatic macrophyte Pistia stratiotes for removal of Cr, Pb and Ni from simulated wastew

It is widely accepted that heavy metal contamination in sediment, soil, and groundwater is one of the largest threats to environmental and human health. Sediments are the principle sinks for heavy metals in aquatic environments and can result in a secondary contamination source affecting the ecosystem. Analysis of heavy metal amounts in sediments and comparison with reference levels is a reliable indicator of ecosystem health, however understanding the distribution of pollutants is among most essential information for environmental research and critical for environmental management and decision-making. 64 samples were collected from surface (0–0.6 m) and subsurface (0.6–1.2 m) layers of sediments in the northern part (bay) of Lake Babrukas, which had undergone pollution by municipal wastewater in 1964–2002. The level of pollution attributed to heavy metals was evaluated using X-Ray fluorescence analysis and comparison with several reference levels (maximum allowable concentrations in soil, background concentrations in Lithuanian soils and background concentrations in Lithuanian lake sediments) in order to determine anthropogenically derived sediment contamination of bottom sediments. Spatial distribution patterns of metals in sediments were demonstrated by employing ordinary kriging interpolation. Results of heavy metal pollution analysis reveal a significant anthropogenic impact on the northern part of Lake Babrukas with concentrations of several heavy metals in both surface and subsurface layers of sediments exceeding not only background concentrations in Lithuanian soils and lake sediments, but even maximum concentrations allowable by Lithuanian legislation. Detected levels of arsenic (As), cadmium (Cd), antimony (Sb), mercury (Hg) and tin (Sn) demonstrate a significant pollution anomaly and high potential threat to the water ecosystem and even human health by exceeding maximum allowable concentration up to 10.6 times, while detected levels of chromium (Cr), copper (Cu), nickel (Ni), and zinc (Zn) show the effects of anthropogenic activity on the lake by exceeding background concentrations in Lithuanian soils and lake sediments up to 7.25 times. A comparison of heavy metal amounts and spatial distribution patterns in the two layers of sediments reveals much higher pollution levels in the subsurface (0.6–1.2 m) than surface (0–0.6 m) level by most metals, namely As, Cd, Hg, Ni, Sb and Sn, while Zn was the only metal with higher concentrations in the surface level. Spatial distribution analysis demonstrates irregular distribution of most metals due to complexity of influencing physical and chemical processes, but the general trend of high concentration anomalies stretching through the south-eastern and north-eastern parts of the bay towards its northern point is explained by former discharges of wastewater into the littoral zone of the eastern shoreline and water currents towards excess water overflow into Lake Lovka (Olauka), interconnected with Lake Babrukas in the north.