Cadmium Toxicity in Water

Cadmium (Cd), a naturally occurring heavy metal, has garnered significant attention due to its widespread presence in the environment and potential adverse effects on ecosystems and human health. This chapter provides a comprehensive overview of the sources, distribution, fate, and toxicological aspects of cadmium in the environment. Industrial processes, mining activities, and agricultural practices are significant contributors to cadmium contamination in the environment, impacting soil, water, and air quality. Additionally, atmospheric deposition of combustion emissions and urbanization also play crucial roles in the dissemination of cadmium pollutants. These diverse anthropogenic activities can lead to the release of cadmium into the environment through various pathways, posing risks to ecosystems and human health. Cadmium's high mobility is influenced by various factors, including pH, redox state, and ionic strength. Despite this, Cd can endure in solution via water-soluble complexes like CdCl⁻ and Cd(SO₄)₂²⁻, and interacts with dissolved organic matter. Overall, cadmium toxicity is a serious health and environmental concern, necessitating vigilant monitoring and precautionary measures to safeguard human health and ecological integrity. This overview aims to aid researchers, policymakers, and environmental practitioners in tackling cadmium contamination and fostering sustainable environmental management.

Heavy metals are serious pollutants and their accumulation in the environment imposes great effects on environmental ecology. Cadmium contamination is one of the heavy metals that is currently becoming a serious concern worldwide due to its high toxicity effects leading to worse results on both environmental and human health. This is particularly due to the consumption of plants with cadmium deposition. This chapter makes a critical review by highlighting sources of cadmium in soil, its accumulation, permissible levels, uptake mechanism and translocation in plant tissue, and its toxicity effects on the plant and humans. Also, the scope of this paper describes various remediation strategies currently available for reducing cadmium accumulation in the soil as well as in plants.

The chapter begins with an introduction that familiarizes readers with cadmium as a toxic heavy metal and its various sources, including industrial activities, soil and water contamination, and cigarette smoke. The objective of the chapter is then presented, which is to delve into the health risks associated with cadmium toxicity. The second section focuses on cadmium uptake and accumulation in the body. It explains the different routes through which cadmium enters the body, such as inhalation, ingestion, and dermal absorption. Furthermore, the chapter explores the bioavailability and absorption mechanisms of cadmium in different organs. The factors influencing the accumulation and distribution of cadmium within the body are also discussed in detail. Moving on to the core of the chapter, the third section examines the wide-ranging health effects caused by cadmium exposure. Both acute and chronic effects are explored, with an emphasis on the organs most heavily impacted by cadmium, including the kidneys, liver, lungs, and bones. Furthermore, the chapter delves into the mechanisms by which cadmium induces its toxic effects, such as oxidative stress, disruption of cellular processes, and interference with essential nutrients. The subsequent sections offer a deeper exploration of specific health risks associated with cadmium toxicity. The chapter discusses the link between cadmium exposure and kidney disease, detailing the mechanisms through which cadmium affects renal function and presenting epidemiological evidence supporting the association. Similarly, the respiratory effects of cadmium are examined, highlighting the risk of chronic obstructive pulmonary disease (COPD) and lung cancer due to cadmium-induced inflammation, fibrosis, and impaired lung function. Additionally, the detrimental impact of cadmium on bone health is explored, with an emphasis on the interference with bone metabolism, decreased bone mineral density, and increased risk of osteoporosis and fractures. The chapter also addresses other health risks related to cadmium toxicity, such as cardiovascular diseases, reproductive disorders, and cancer. The mechanisms by which cadmium contributes to the development of these conditions are discussed in depth, underlining the urgent need for preventative measures and interventions to reduce cadmium exposure. In conclusion, this book chapter provides a comprehensive overview of the health risks associated with cadmium toxicity. By exploring the mechanisms through which cadmium induces toxicity and examining its impact on various organs and systems, the chapter highlights the importance of awareness, prevention, and regulations to mitigate cadmium exposure. It concludes by offering recommendations for future research and actions to minimize the adverse health effects of cadmium.

Cadmium, a toxic heavy metal, has gained significant attention due to its detrimental effects on the nervous system. This book chapter provides a comprehensive overview of cadmium's neurotoxic effects, highlighting the importance of studying its impact on neurohealth. The chapter begins with an introduction that outlines cadmium as a toxic heavy metal and emphasizes the need to understand its neurotoxic effects. It then delves into the sources and exposure routes of cadmium, including natural and anthropogenic sources, occupational exposure, and dietary intake. The implications of cadmium contamination in food are also discussed in this section. Next, the chapter explores the absorption and distribution of cadmium within the body, focusing on the mechanisms of absorption, tissue distribution, and factors influencing cadmium metabolism. This understanding sets the stage for a detailed exploration of the neurological effects of cadmium. It highlights cadmium-induced neurotoxicity, its manifestations, and the impacts on the central nervous system (CNS). The chapter also investigates the neurodevelopmental effects, cognitive impairments, behavioral changes, and psychological disorders associated with cadmium exposure. The mechanisms underlying cadmium neurotoxicity are then examined, including oxidative stress and reactive oxygen species (ROS) generation, mitochondrial dysfunction, neurotransmitter and synapse function impairment, inflammation, immune responses in the CNS, and epigenetic alterations. The chapter further explores the connection between cadmium exposure and neurodegenerative diseases, including Alzheimer's and Parkinson's disease, along with other conditions associated with cadmium exposure. The vulnerability of certain populations, such as children and the aging population, to cadmium neurotoxicity is addressed, as well as potential gender differences. The chapter also discusses various methods and techniques for detecting and assessing cadmium neurotoxicity, including biomarkers, measuring cadmium concentration in biological samples, and neurological assessment methods. Moreover, preventive measures and mitigation strategies are outlined to address cadmium neurotoxicity. Occupational safety measures and environmental policies are discussed, along with dietary guidelines and pharmacological interventions such as chelating agents. In conclusion, the chapter summarizes the neurotoxic effects of cadmium, emphasizes the significance of further research, and provides strategies for reducing cadmium exposure and safeguarding neurohealth. This comprehensive examination of cadmium and its neurotoxic effects contributes to our understanding of the potential risks associated with cadmium exposure and informs future research endeavors to protect individuals from its deleterious effects on the nervous system.

Cadmium (Cd) is a highly poisonous heavy metal that presents a considerable hazard to the environment and human health. It can move from water to soil, then food crops and accumulate in their edible parts. When it becomes part of the food chain, it causes toxic effects to human life via kidney damage to even cancers. Numerous methods have shown varied efficacies for its remediation from contaminated environments. One method that has shown promising results with sustainable Cd removal is phytoremediation, which involves phytoextraction, rhizofiltration, phytostabilization, and phytostimulation through diverse plant species. Based on Cd uptake in aerial part of plant three types of plants are existed and exploited for phytoremdiation such as hyperaccumulator (concentrate substantial amount of Cd in shoot with BCF > 1), excluder (concentrate tiny amount of Cd in shoot with BCF < 1), and indicator plants (concentrate reasonable amount of Cd in shoot with BCF = 1). Numerous plant species have been exploited for remediation of Cd in water (Eichhornia crassipes, Pistia stratiotes, Lemna minor), whereas in soil (Brassica spp., Sedum alfredii, Populus alba, Alyssum murale, Helianthus annuus, Thlaspi caerulescens, Zea mays). This chapter critically reviewed the sources, and toxicity of Cd. Finally, selection criteria of plant, merits and demerits and types of phytoremediation elaborated in detail for remediation of Cd contaminated water and soil resources for achieving sustainable development.

Cadmium (Cd) is a highly toxic heavy metal that poses serious environmental risks due to its persistence and bioaccumulation in various ecosystems. Traditional methods of Cd remediation, such as chemical precipitation and adsorption are not environment-friendly and expensive. In recent years, bioremediation has emerged as a promising and sustainable alternative for the removal of Cd from contaminated environments. This review explores the various microbial strategies (bioaugmentation, mycoremediation, phycoremediation, phytoremediation, nano bioremediation, microbial fuel cells, microbial consortia, and biofilm applications) employed for potential removal of Cd from soil and water resources, emphasizing their efficiency, applicability, and prospects. We also elaborated different mechanisms (such as biosorption, bioprecipitation, bioleaching, bioaccumulation, biotransformation, sequestration, phytoextraction, phytostabilization, rhizofiltration, and molecular mechanisms) responsible for Cd removal from wastewater. This review provides valuable insights into harnessing the power of microorganisms to combat Cd pollution effectively.

Wastewater produced from industrial and municipal processes has been reported for heavy metal contamination. Amongst them, cadmium (Cd) concentration has been reported (up to 0.02 mg/L) in Pakistan, (up to 0.03 mg/L) in China and (up to 0.07 mg/L) in India, which is quite higher than the standard limits of WHO (0.003 mg/L). It has serious implications for human health, getting into the tissues via direct ingestion, dermal contact, inhalation, and adsorption. Several methods have been explored for the extermination of Cd from the environment. Conventional methods (such as adsorption, chemical precipitation, membrane filtration, electrodialysis, photocatalysis) of metal removal are constrained by the processing problems, expenses, and the generation of toxic sludge, therefore more research is now focused on the use of advanced treatment methods (such as fluidized bed reactor, advanced oxidation process, nanotechnology, hybrid system method, chelation, solvent extraction, foam fractionation, cryogens, graphene, carbon nanotubes, activated carbon, zeolites, microbial fuel cells, and phytoremediation) for the removal of Cd metal ions from the wastewater. These advanced processes may be cost-effective, viable, more efficient and less time taking than the existing techniques and have intense opportunity.

Cadmium is a compound toxic, which can induce adverse effects on the different organs like heart, kidneys, liver, lung, and their exposition has been linked with cancer in humans, hence important remove it of sites contaminated with it. Some methods are used to eliminate this metal from differents contaminated places. The objective of the present work, was analyze the remediation of the heavy metal with nine natural obtained from fungal strains fungi from samples of soil contaminated of zone high-rish, and one of a place near the Universitary zone of San Luis Potosí, S.L.P., México, finding that the biomasses of Purpureocillim lilacinium, Aspergillus flavus, Penicillium sp-1, and Aspergillus terreus, had the best removal rates of the metal (with dithizone at 518 nm), with a removal between 76 and 99%, in the conditions analyzed. These biomasses are a great alternative for the elimination of this and other contaminants from the different high-risk sites, and in this study, the hability of eliminate this contaminant by environmental polluting fungus strain of Purpureocillim lilacinium, was analysed.

Cadmium (Cd) is a toxic heavy metal that poses a significant threat to the environment and human health due to its persistence and ability to accumulate in various ecosystems. In recent years, the use of microbial bioremediation strategies to mitigate the adverse effects of cadmium toxicity has gained considerable attention. Native soil bacteria have emerged as promising candidates for bioremediation due to their adaptability to diverse soil environments and ability to interact with heavy metals. This abstract highlights the potential of microbial native soil bacteria in combating cadmium toxicity. Firstly, it explores how these bacteria can alleviate cadmium toxicity, including metal sequestration, enzymatic detoxification, and bioaccumulation. Native soil bacteria possess various physiological and genetic adaptations that enable them to survive in cadmium-contaminated soils and tolerate high levels of cadmium exposure. The abstract discusses the interactions between native soil bacteria and plants in the context of cadmium remediation. Certain soil bacteria have been found to form symbiotic associations with plants, enhancing their cadmium tolerance through mechanisms such as phytoextraction, rhizodegradation, and rhizofiltration. These interactions hold great potential for developing efficient and sustainable strategies for cadmium bioremediation. The abstract also discusses the challenges of applying native soil bacteria for cadmium bioremediation. Factors such as microbial competition, nutrient availability, pH, and temperature can influence the effectiveness of microbial remediation approaches. Therefore, optimizing bacterial growth and activity conditions is crucial for maximizing their remediation potential. Utilizing microbial native soil bacteria represents a promising approach for mitigating cadmium toxicity. Their unique adaptations and interactions with plants provide potential solutions for remediating cadmium-contaminated soils and reducing the associated environmental and health risks. Further research and development in this field are necessary to optimize the efficacy of microbial bioremediation strategies and facilitate their practical implementation on a larger scale.

The contamination of soils with heavy metals poses a significant threat to the environment and human health. Among these heavy metals, cadmium (Cd) is of particular concern due to its persistence, high toxicity, and ability to accumulate in the food chain. The rhizosphere, the region of soil surrounding plant roots, plays a crucial role in the fate and behaviour of Cd in the soil–plant system. This study aims to investigate the toxicity of rhizospheric cadmium-contaminated soil and explore the potential of phytoremediation as an environmentally friendly approach to mitigate Cd pollution. The research utilizes a combination of field surveys, laboratory experiments, and plant growth trials to assess the effects of Cd on soil properties, plant growth, and the remediation potential of selected plant species. The results of the field surveys reveal elevated levels of Cd in rhizospheric soils compared to bulk soils, indicating the accumulation and retention of Cd within the rhizosphere. The increased Cd concentration in the rhizosphere has detrimental effects on soil microbial activity, nutrient availability, and plant growth. The accumulation of Cd in crops grown in contaminated soils risks food safety and human health. To mitigate the toxic effects of Cd, phytoremediation, a plant-based remediation technique, is explored. Various plant species known for their Cd accumulation capabilities, such as hyperaccumulators and metal-tolerant plants, are evaluated for their effectiveness in remediating Cd-contaminated soil. The plant’s ability to extract, accumulate, and detoxify Cd is assessed through plant growth parameters, Cd uptake analysis, and anatomical and physiological changes in plant tissues. The findings demonstrate that certain plant species have the potential to remediate Cd-contaminated soils by reducing Cd concentrations and improving soil quality. These plants can accumulate Cd in their tissues, sequester it in the roots, or translocate it to the aboveground biomass. The rhizosphere microbial community is also vital in facilitating Cd uptake, mobilization, and transformation, enhancing phytoremediation efficiency. Overall, this study emphasizes the importance of understanding the toxicity of Cd in rhizospheric soils and highlights the potential of phytoremediation as a sustainable approach for Cd pollution mitigation. The insights gained from this research contribute to developing strategies for effective soil management and selecting suitable plant species for phytoremediation projects to restore Cd-contaminated environments.

Cadmium (Cd) is considered as one of the most hazardous elements and its existence in crop field is of great environmental concern due to its detrimental impacts, persistence, and intense level of bioaccumulation. In the developing nations, rice is counted as the most essential food crop and over half of the global population relies on rice for the survival. The consumption of rice is a significant dietary source of Cd and may pose human health risk. Therefore, to ensure food safety and reducing Cd toxicity, a comprehensive review incorporating innovative and sustainable, ecofriendly approach are needed. The origin of Cd in paddy soils and effect of dominant soil components like soil pH, soil redox potential on Cd availability, Cd toxicity in rice and genotypic variation in Cd uptake are highlighted in this review. This review also focused on the application of various organic and inorganic amendment to reduce Cd accumulation in rice plant. Moreover, this review provides an insight of Fe plaque formation and its adsorptive action to decrease Cd addition in rice. Furthermore, the present review discusses the Cd transport mechanism in rice and future research thrusts and guidelines to moderate Cd uptake in rice.

Under favourable circumstances, reactive oxygen species (ROS) is frequently produced at safe levels and controlled by multifarious networks. The delicate equilibrium between ROS (O₂^•−, H₂O₂, ¹O₂, ^•OH) origination and ROS scavenging is constantly disordered by environmental stress factors like drought, heat, salinity and heavy metal. The heavy metal ions including Cd extensively disrupt redox homeostasis making ROS extremely deadly and impair cellular homeostasis. This in turn indicates scanty plant health and crop output. To ensure the existence and adapt to such Cd mediated stress conditions, plants have amalgamated antioxidant machinery having two well equipped arms, enzymatic superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR), glutathione peroxidase (GPX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR) and non-enzymatic ascorbic acid (AsA), glutathione (GSH), carotenoids, α-Tocopherol, phenol, proline. These two arms scavenge ROS in a cooperative fashion. In this study, we pivot on Cd stress mediated ROS generation, ROS chemistry and localization and their scavenging mechanism resolved by both arms of the antioxidative defence systems, emphasizing their promising role in Cd stress tolerance. Such inclusive knowledge on antioxidant defence will permit us to evolve genetically engineered Cd stress-tolerant plants.

Cadmium (Cd) is one of the non-essential, extremely harmful contaminants that are generating major environmental and agricultural issues globally. From germination to yield, plants are harmed by Cd toxicity, but the magnitude of the harm depends on the dosage and the period of exposure. Due to prolonged Cd exposure, it interference with enzymatic and photosynthetic activities, as well as membrane degradation whereas, seed germination and plant growth are reduced. At higher levels, Higher levels of cadmium exposure disrupt plant nutrition and water relationships and result in oxidative damage. Additionally, Cd-induced structural alterations in the photosynthetic system reduce crop yield. Cd can be removed from and stabilized in soil by phytoremediation, whereas Cd can also be absorbed into the bodies of microorganisms. Increased Cd absorption in hyper accumulator plants to remove and change the poisonous form of Cd into harmless forms. Cd can be washed out, immobilized, and stabilised in the soil using chemical treatments during chemical remediation. Due to its eco-friendly characteristics, bioremediation of polluted environments is regarded as effective and credible. Furthermore, the application of nutrients antagonistic to Cd reduce uptake and toxicity in crops. The pH of the soil may be raised by the organic additions, and they may also bind to its functional groups, create complexations, and turn exchangeable forms into residual ones. Adopting certain agricultural practises is also found to be beneficial in lowering Cd uptake and accumulation in plants and harvesting high-quality food from Cd-contaminated soils.

Zinc (Zn) deficiency and cadmium (Cd) toxicity in soils are both responsible for poor agronomic performance of crops. Mung bean was grown in a greenhouse under Cd contamination. Zn was applied to reduce the adverse effect of Cd on growth and yield of Mung beans. Zn and Cd rates (mg kg⁻¹) were 0, 5, 10, 20 and 0, 2, 4, respectively. Basal Zn supply boosted about 26% of yield and replenished 30% yield loss of Mung beans due to Cd contamination. Approximately 35% decline of grain yield was found due to Cd contamination in the soils as compared to Cd control. The decrease in grain yield per plant under Cd toxicity conditions was the result of reduced number of seeds per pod, 100 seed weight and number of seeds per plant. Improved grain yield was due to a significant increase in the number of pods, number of grains per pod and 100 grain weight owing to enhanced chlorophyll pigments in Mung bean leaves. Among the basal Zn application @ 5 mg Zn kg⁻¹ soil was the best viable option to obtain a larger yield of Mung beans for Cd contaminated soils.