Meththika Vithanage

Ecosphere Resilience Research Center · Faculty of Applied Sciences-University of Sri Jayewardenepura-Nugegoda-Sri Lanka

A composite material prepared from municipal solid waste-derived biochar and montmorillonite (MSW-BC-MMT) was studied as a remediation medium for the removal of oxytetracycline (OTC) from aqueous systems. The morphological characterization using SEM images revealed that the composite had a heterogeneous flaky, plate-like surface appearance. Based o...

Arsenic (As) is known as an extremely toxic metalloid available in the environment due to both anthropogenic and geogenic activities. Even though adsorption has shown promising results in remediating As, the speciation of As poses a challenge. Bioavailability and mobility of As can be potentially improved with the addition of biochar to contaminate...

Arsenic (As) is recognized as a persistent and toxic contaminant in the environment that is harmful to humans. Biochar, a porous carbonaceous material with tunable functionality, has been used widely as an adsorbent for remediating As-contaminated water and soils. Several types of pristine and modified biochar are available, and significant efforts...

Microplastics (MPs) and SARS-CoV-2 interact due to their widespread presence in our environment and affect the virus' behaviour indoors and outdoors. Therefore, it is necessary to study the interaction between MPs and SARS-CoV-2. The environmental damage caused by MPs is increasing globally. Emerging pollutants may adversely affect organisms, espec...

The emergence of novel respiratory disease (COVID-19) caused by SARS-CoV-2 has become a public health emergency worldwide, subsequently causing distressing consequences on the world economy and ecosystem services. Despite growing facts reported in the literature on the presence of SARS-CoV-2 in different environmental compartments, the virus's tran...

Microplastics can act as a vector to transport various organic and inorganic contaminants. Hydrophobic and hydrophilic organic contaminants tend to bind to microplastics due to their hydrophobicity and high surface area to volume ratio. Recent studies have focused their attention on evaluating the ability of microplastics to bind potentially toxic...

Microplastics and caffeine co-occur in wastewater due to their vital usage. The hydrophobicity of microplastics enriches their potency to interact with caffeine in water, however studies on vector transportation of microplastic-bound caffeine is still in its infancy. Therefore, caffeine adsorption to pristine and aged polyethylene (PE) microplastic...

Soil and water contamination with toxic metal(loid)s (TMs) has increased globally in the present era due to rapid industrialization, improper waste disposal, application of chemical fertilizers and pesticides, mining and other anthropogenic activities. Most of them are toxic even at low concentrations, persistent in the environment, and cannot be d...

Fluoride () is one of the essential elements found in soil and water released from geogenic sources and several anthropogenic activities. Fluoride causes fluorosis, dental and skeletal growth problems, teeth mottling, and neurological damage due to prolonged consumption, affecting millions worldwide. Adsorption is an extensively implemented techniq...

Abundance of buried microplastics in sand profiles and pellet pollution index at Sarakkuwa beach, at west-coast of Sri Lanka was studied as a case study due to the receival of plastic nurdles and debris from the MV X-Press Pearl ship disaster in May 2021. Sand collected at 7 locations to a depth of 2 m in different depths for a beach segment of 200...

Landfilling is the most widely used disposal method for municipal solid waste around the world. The main disadvantage of this strategy is the formation of leachate, among other aspects. Landfill leachate contains highly toxic and bio-refractory substances that are detrimental to the environment and human health. Hence, the risk of discharging poten...

Microplastics has become a global concern due to their ubiquitous presence which poses unavoidable human exposure risks. Geographical distribution and yearly trends of research on microplastics, food, and beverages do not exist. Thus, no overall account is available regarding the presence of microplastics and plastics-associated contaminants in foo...

Water usage increased alongside its competitiveness due to its finite amount. Yet, many industries still rely on this finite resource thus recalling the need to recirculate their water for production. Circular bioeconomy is presently the new approach emphasizing on the ‘end-of-life’ concept with reusing, recycling, and recovering materials. Microal...

Endocrine-disrupting chemicals (EDCs) such as natural estrogens, bisphenol A, and nonylphenol are widely spread in the environment due to improper waste disposal. Emergence of EDCs mainly occurs from widely used consumer products like pharmaceuticals, personal care products, plastic preservatives, pesticides, and industrial lubricants. Both acute a...

Absract This study sought to reckon the efficacy of activated carbon from pomegranate peels (ACPP) in removing Basic Red 46 (BR46). The yielded sample was then characterized by XRD, FTIR, SEM/EDS, BET/BJH, pHpzc, and Boehm titration, showing an amorphous and mesoporous structure with a specific surface area of 102.068 m² g⁻¹, along with the sight o...

Contagious diseases are needed to be monitored to prevent spreading within communities. Timely advice and predictions are necessary to overcome the consequences of those epidemics. Currently, emphasis has been placed on computer modelling to achieve the needed forecasts, the best example being the COVID-19 pandemic. Scientists used various models t...

The sorption medium plays a vital role in vector transport of microplastics bound metal ions. The influence of soapy water on transportation of microplastics bound Cr(VI) and sorption mechanisms are still not clear. Therefore, in the present study the performance of pristine and aged polyethylene (PE) microplastics to adsorb Cr(VI) in soapy water w...

The scientific revolution in omics technologies has paved the way for emerging technologies in wastewater treatment. These approaches have been adopted to investigate the metabolic potential, diversity, and spatiotemporal dynamics of microorganisms in wastewater systems. The prokaryotic, eukaryotic diversity can be utilized in industrial wastewater...

Chronic kidney disease of unknown etiology (CKDu) is receiving considerable attention throughout the world due to its severe threat to human health. However, the linkage between dissolved organic matter (DOM) in groundwater to CKDu is still unclear, especially at molecular level. Herein, the molecular differences of DOM between groundwaters related...

Chronic kidney disease of unknown etiology (CKDu) has posed a serious threat to human health around the world. The link between the prevalence of CKDu and groundwater geochemistry is not well understood. To identify the potential geogenic risk factors, we collected 52 groundwater samples related to CKDu (CKDu groundwater) and 18 groundwater samples...

This study was envisaged to understand the effect of increasing pyrolysis temperature on the Cr(VI) removal potential of the groundnut shells derived biochars. The biochars were prepared at four different pyrolysis temperatures (350 °C, 450 °C, 550 °C, 650 °C) and were used unmodified to examine the adsorption potential for Cr(VI). Influence of bio...

Poly- and per-fluoroalkyl substances (PFAS) are synthetic chemicals and reach the terrestrial and aquatic environments through anthropogenic activities. Aqueous, film-forming foam used in firefighting and disposal of solid (e.g., dewatered biosolids) and liquid (e.g., sewage effluent) wastes are major sources of PFAS in soil. Because of the strong...

Vanadium is an essential element for humans and animals. The toxicity of vanadium at higher concentrations could be a global environmental concern and a significant issue for both environmental protection and economic benefits. The relevance of anthropogenic vanadium in the environment has increased significantly in recent years due to an increased...

Several health issues are related to toxic metals among which Pb, Cr, Cd, and Ni are categorized as human carcinogenic. We analyzed the health risks linked with food chain contamination due to vegetables irrigated with wastewater containing metals. Thirty-six samples of each vegetable, water, and soil (at two depths, 0–15 cm, and 15–30 cm) were col...

Hydroxyapatite (HAP) is an easily synthesizable, low-cost mineral that has been recognized as a potential material for fluoride removal. Some of the synthesis methods of HAP are quite straightforward and cost-effective, while some require sophisticated synthesis techniques under advanced laboratory conditions. This review assesses the physicochemic...

Nanoplastics are emerging contaminants of concern for living organisms and ecosystems, yet nanoplastics are difficult to extract and analyse. Once released into the environment, the fate and behavior of nanoplastics are controlled by physical, chemical, and biological factors. Here, we review nanoplastics weathering, aggregation, biofouling, and bi...

The rapid increase in population growth due to industrialization and urbanization has resulted in air quality deterioration in Pakistan. Consequently, a considerable increase has been seen in the types of sources of air pollutants. However, the air quality of the country has deteriorated in the absence of management capabilities against air quality...

In this study the multiple metal(loid) (As, Cd, Cu and Ni) resistant bacterium Serratia sp. KUJM3 was able to grow in both single and multiple metal(loid) contaminated wastewater and remove them by 34.93–48.80% and 22.93–32%, respectively. It reduced As(v) to As(III) by 68.44–85.06% in a concentration dependent manner. The strain's IAA production p...

In recent years, biomass has been reported to obtain a wide range of value-added products. Biochar can be obtained by heating biomass, which aids in carbon sinks, soil amendments, resource recovery, and water retention. Microwave technology stands out among various biomass heating technologies not only for its effectiveness in biomass pyrolysis for...

Biochar is a carbon-rich material resulting from the pyrolysis of plant and animal biomass. Biochar has a long history as a soil amendment for centuries since the Mayan civilization. Attaining sustainability in agriculture is not easy; however, the addition of biochar may reduce the adverse effects of numerous malpractices in conventional agricultu...

Menstrual hygiene waste management has received lack of attention and hence it has been poorly investigated, mainly due to its association to social and cultural aspects of a natural process, that is often surrounded of entrenched stigma and taboos. Therefore, data about quantities and full lifecycle of the generated waste are often not available o...

This work aimed to study the synthesis of Mg/Al layered double hydroxides (LDH) from aluminum residues. LDH was produced by co-precipitation and hydrothermal methods using Al(OH)3 synthesized from aluminum residue. It was possible to confirm the formation of LDH, with an increase in crystallinity for the hydrothermal synthesis. The FTIR indicates n...

Anthropogenic and natural sources influence trace metals (TMs) bound to different sized particulate matter (PM) in dry and wet atmospheric deposition, which can create ecosystem and human health issues in the long run. Limited reviews are available summarizing worldwide concentrations in TMs in atmospheric PMs, their sources and pathways. Simultane...

Poly- and perfluoroalkyl substances (PFAS) are synthetic chemicals, which reach terrestrial and aquatic environments through anthropogenic activities. Major sources of PFAS in the environment include fire-fighting foams (aqueous film forming foam (AFFF)), wastewater sources, biosolids, and composts. Limited information is available about PFAS in wa...

To preserve the quality of life, numerous products containing inorganic and organic hazardous materials increased, which led to uncontrolled disposal of them to the environment. Among many contaminants, toxic metals can cause deleterious effects to the environment and target organisms even at trace levels. The removal of noxious contaminants from t...

Particulate plastic fragments (micro and nano-plastics) in aquatic environments provide abundant solid sub-strates, which serve as an important habitat for a variety of microorganisms. Surfaces of microplastics (MPs) exhibit hydrophobicity that facilitate the adsorption of dissolved organic carbon (DOC) in the aquatic environment. Furthermore, MPs...

Extensive use of Poly- and perfluoroalkyl substances (PFASs) in various industrial activities and daily-life products has made them ubiquitous contaminants in soil and water. PFAS-contaminated soil acts as a long-term source of pollution to the adjacent surface water bodies, groundwater, soil microorganisms, and soil invertebrates. While several re...

The Virtual Special Issue entitled “Tackling Water Security” is mainly focused on water availability, water quality, management, governance, biotic or abiotic emerging contaminants and policy development in the Anthropocene. The issue is further dedicated to highlight the new opportunities and approaches to elevate the efficiency of water treatment...

Chronic kidney disease of unknown etiology (CKDu) becomes a health concern in developing countries. It is urgent to recognize CKDu-related groundwater in CKDu-prevalent areas. Here, spectral indices showed that DOM from CKDu groundwater was characterized by higher molecular weight, stronger exogenous feature, and greater degree of humification and...

The objectives of the research was to assess the coastal pollution by plastic nurdles, pyrolitic debris, associated potential toxic elements (PTEs) concentrations and mitigatory efforts by the worst ever maritime accident of a chemical and plastic boarded container vessel; MV X-press Pearl. Field sampling was carried out three times during May, Jun...

The invasive nature of cyanotoxin-producing cyanobacteria and the adverse effects concerning their toxic impacts have gained heightened scientific attention of late. The persistence of cyanotoxins in irrigation water leads to bioaccumulation in plants, the development of phytotoxic effects, and the threat of groundwater contamination. The accumulat...

The objectives of the study were to evaluate and compare the efficacy of hexavalent chromium (Cr(VI)) removal by amino-modified (HDA-MPBC) and pristine biochar (MPBC) derived from an invasive plant Mimosa pigra. Prepared biochars were characterized and batch experiments were conducted to check the performance and the mechanisms of Cr(VI) removal. F...

This study proposes a modular floating biofilm reactor (MFBR) for in situ nitrogen removal from slightly polluted water in rivers using enriched indigenous microorganisms. Its main structure is a 60 cm × 60 cm × 90 cm rectangular reactor filled with hackettens. After a 96-day startup, the removal efficiencies of ammonia-N and total N (TN) reached 8...

The global data on the temporal tracking of the COVID-19 through wastewater surveillance needs to be comparatively evaluated to generate a proper and precise understanding of the robustness, advantages, and sensitivity of the wastewater-based epidemiological (WBE) approach. We reviewed the current state of knowledge based on forty scientific articl...

This study aimed at recovering nutrients from human urine as valorized products through chemical and biological mineralization, and assessing their fertilizer potential. Chemosynthesis of struvite (MgNH4PO4 ⋅6H2O) was accomplished from fresh human urine through chemical mineralization using magnesia, whereas biogenic synthesis was achieved through...

Objectives of the present research were to examine the capacity of disc-milled high lignin biochar colloids (CBC) for the removal of ciprofloxacin (CPX) from aqueous solution and synthetic hydrolyzed human urine. In this study, adsorption of CPX was tested against the initial pH (3–10), ionic strength (0.001–0.1 M NaNO3), resident time (up to 8 h),...

The objective of this research was to evaluate the efficacy of cinnamon wood biochar (CWBC) in adsorbing sulfamethoxazole (SUL), which alleviates bioavailability and plant uptake. Batch studies at various pH, contact times, and initial SUL loading were used to study SUL adsorption in CWBC, soil, and 2.5% CWBC amended soil. SUL mitigation from plant...

One of the key focuses of the agricultural industry for preventing the decline in crop yields due to pests is to develop effective, safe, green, and sustainable pesticide formulation. A key objective of industry is to deliver active ingredients (AIs) that have minimal off site migration and non-target activity. Nanoporous materials have received si...

Antimony (Sb) is introduced into soils, sediments, and aquatic environments from various sources such as weathering of sulfide ores, leaching of mining wastes, and anthropogenic activities. High Sb concentrations are toxic to ecosystems and potentially to public health via the accumulation in food chain. Although Sb is poisonous and carcinogenic to...

In the present study, microwave co-pyrolysis (MCP) was used to simultaneously convert medical plastic waste (MPW) and waste frying oil (WFO) into liquid oil products. The MCP process demonstrated a faster heating rate (24 • C/min) and shorter process time (20 min) compared to conventional pyrolysis techniques converting MPW and WFO into liquid oil...

Wastewater is degraded and discarded water inevitably and ubiquitously generated from human facilities and anthropogenic activities, and discharged into the environment. It is a cocktail of countless chemicals, both beneficial and harmful ones ranging from organic matter to toxic metals, nutrients to persistent organic pollutants and pathogens, and...

During recent decades, agriculture production has intensified by using a large number of chemical substances as pesticides to protect crops from unwanted fungi, weeds, and insects. It has been reported that long-time exposure of pesticides to different environmental conditions results in persistence of many derivatives of them in the environment. I...

Hydroxyapatite (HAP) (Ca10(PO4)6(OH)2) is a calcium phosphate mineral that is considered as one of the widely used inorganic biocompatible materials for contaminant removal. This is a particular composition that specific methods can easily produce as dry methods, wet methods, high-temperature processes, from biogenic sources and a combination of fe...

Biochar application has long been recognized as one of the best approaches for sustainable agriculture. In this regard, studies involved investigating the impact of various biochar types on a wide range physicochemical and biological properties of different soil types and the growth performance of crop species. Although the studies focus on the div...

The new coronavirus (COVID-19) has become a global pandemic within a short period. Current attention is to restrict its direct transmission. However, the focus on secondary transmission via wastewater is lacking. The virus has been identified in fecal matter, raw wastewater, sewage samples, urine, secondary treated effluent, etc., in different coun...

Among Sri Lanka's River basins Kala Oya basin third largest catchment (2.87x10 9 m 2), and one of the most widely used sources of water for irrigation, water supply, and other diversions. The North Central and North Western provinces are known to be having bi-seasonal climates that are dry season and rainy season. In the dry season, people tend to...

Ambient temperature in Sri Lanka greatly influences each and every venture throughout the island. The gradual climate change in global scale further worsens the existing situation causing tremendous impacts. The primary objective of this study is to assess the presence and significance of linear temperature trends in climatological zones in Sri Lan...

The Martian critical zone, especially its soil‐atmosphere interface, may host an active halogen cycle affecting habitability, as inferred from halogen trends observed in situ at Gusev and Meridiani, along with oxychlorine species detected in situ. However, the sinks and sources of the Martian halogen cycle remain poorly constrained, especially for...

The contamination of natural resources by hexavalent chromium (Cr(VI)) originating from natural and anthropogenic activities is a serious environmental concern. Although many articles on chromium remediation have been published, a comprehensive understanding of the mechanisms involved in remediation with different sorbents is not yet available. In...

This review focuses on existing technologies for carcass and corpse disposal and potential alternative treatment strategies. Furthermore, key issues related to these treatments (e.g., carcass and corpse disposal events, available methods, performances, and limitations) are addressed in conjunction with associated environmental impacts. Simultaneous...