Meththika Vithanage

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

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...

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...

13.1 Trace metal(loids) contamination in water Trace metal(loids) are elements that exhibited harmful effects on the environment and the living organisms , including humans, when reaching over a threshold level. In few decades, trace metal contamination in the environmental matrixes is a grave concern. Since the trace metals are stable at various c...

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...

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...

Sulfamethoxazole (SUL) is one of the sulfonamide antibiotics used to treat the urinary infections in human and veterinary animals. About 30% of SUL is excreted through the urine in the unmetabolized form and hence it possibly contaminates water sources. Thus, it is essential to remove the SUL from the water in a greener and cost-effective manner. T...

Land application of sewage sludge is increasingly used as an alternative to landfilling and incineration owing to a considerable content of carbon and essential plant nutrients in sewage sludge. However, the presence of chemical and biological contaminants in sewage sludge poses potential dangers; therefore, sewage sludge must be suitably treated b...

Particulate matter (PM) is a complex mixture of solid particles and liquid droplets suspended in the air with varying size, shape, and chemical composition which intensifies significant concern due to severe health effects. Based on the well-established human health effects of outdoor PM, health-based standards for outdoor air have been promoted (e...

Background: Microplastics are lightweight materials, and found ubiquitously in the aquatic environment due to the discharge of primary and secondary plastics. Pb2+ is a common micropollutant found in water discharged from wastewater from industries, service stations, and landfill leachate. Thus, microplastics are considered as a vector to transport...

The scope of environmental remediation governed by biochar is limited to that of activated carbon due to its lower functionality and lower surface area. Incorporation of clay to biochar could possibly impart excellent sportive properties to treat a diverse range of pollutants effectively through adsorption. Clays are considered as natural pollutant...

Biochar has widely been utilized as an agricultural soil amendment owing to its enhanced surface properties and cost-effectiveness. In the present work, the influence of tea waste biochar (TWBC) upon acid modification on Allium cepa L. (red onion) growth has been studied. Its effect as a soil amendment has also been studied by assessing the nutrien...

The removal of excessive ammonium from water is vital for preventing eutrophication of surface water and ensuring drinking water safety. Several studies have explored the use of biochar for removing ammonium from water. However, the efficacy of pristine biochar is generally weak, and various biochar modification approaches have been proposed to enh...

With the ever-increasing demand for lithium (Li) for portable energy storage devices, there is a global concern associated with environmental contamination of Li, via the production, use, and disposal of Li-containing products, including mobile phones and mood-stabilizing drugs. While geogenic Li is sparingly soluble, Li added to soil is one of the...

The purpose of this study was to assess the effect of cinnamon wood biochar (CWBC) in minimizing the plant uptake of sulfamethoxazole (SUL) from the contaminated soil. For this purpose, Ipomoea aquatica was grown in soil and 2.5% w/w CWBC amendment contaminated with 50 mg/kg of SUL for 4 weeks. The results suggest that the root uptake of SUL relati...

Research on microplastics (MPs) primarily focuses on the abundance in different ecosystems, ecotoxicology and health aspects. The primary focus is now on structural and physicochemical changes in soil, ecotoxicology and influence on plant growth performance. Compost is considered one of the prime sources of MPs in agricultural environments, where M...

Polycyclic aromatic hydrocarbons (PAHs) are generated due to incomplete burning of organic substances. Use of fossil fuels is the primary anthropogenic cause of PAHs emission in natural settings. Although several PAH compounds exist in the natural environmental setting, only 16 of these compounds are considered priority pollutants. PAHs imposes sev...

The study was designed to determine the variations in the diversity and the total abundance of airborne bacteria in the atmosphere of nine locations in Kandy City, the cultural capital of Sri Lanka. Culturable microorganisms were identified using 16S rDNA sequencing. Quantification of total bacterial abundance was calculated using real-time PCR. Tw...

Hierarchical porous carbon (HPC) has attracted increasing research interest for energy and environmental applications. HPC is conventionally fabricated by activated carbon, which potentially causes hidden environmental burdens. To overcome this issue, biochar, a promising renewable precursor, offers an attractive raw material substitute and has alr...

Recently, the adsorption-based environmental remediation techniques have gained a considerable attention, due to their economic viability and simplicity over other methods. Hence, detailed presentation and analysis were herein focused on describing the role of biochar in oil spill removal. Oil removal by utilizing biochar is assumed as a green-orie...

The prevalence of chronic kidney disease of unknown etiology (CKDu) is receiving considerable attention due to the serious threat to human health throughout the world. However, the roles of geo-socio-environmental factors in the prevalence of the CKDu endemic areas are still unknown. Sri Lanka is one of the countries most seriously affected by CKDu...

The escalating loads of municipal solid waste (MSW) end up in open dumps and landfills, producing continuous flows of landfill leachate. The risk of incorporating highly toxic landfill leachate into environment is important to be evaluated and measured in order to facilitate decision making for landfill leachate management and treatment. Leachate p...

Fluoride as a geogenic contaminant is commonly encountered in groundwater-based drinking water sources. In the present study Watermelon Rind (Citrullus lanatus) Biochar (WMRBC) was investigated for its defluoridation potential. The factors affecting the removal of fluoride, including pH, adsorbent dosage, initial concentration, and contact time wer...

Biochar is produced as a charred material with high surface area and abundant functional groups by pyrolysis, which refers to the process of thermochemical decomposition of organic material at elevated temperatures in the absence of oxygen. The carbon component in biochar is relatively stable, and, hence, biochar was originally proposed as a soil a...

Aqueous film-forming foam, used in firefighting, and biowastes, including biosolids, animal and poultry manures, and composts, provide a major source of poly- and perfluoroalkyl substances (PFAS) input to soil. Large amounts of biowastes are added to soil as a source of nutrients and carbon. They also are added as soil amendments to improve soil he...

Modification of biochar for efficient removal of antibiotics from water could be a valuable approach in the environmental applications. In this study, a brown seaweed (Sargassum crassifolium) was pyrolyzed at 500 ºC and the obtained biochar (SWBC) was modified with zeolite through the slurry method maintaining the ratio at 1:5 (zeolite: biochar) (S...

Municipal solid waste (MSW) has ranked among the most detrimental global issues of the decade, where it has been induced by the population trends, urbanization, and economic growth. The majority of conventional pollution treatment methods involve high capital and maintenance costs with sophisticated instruments and technology. Biomass valorization...

Experimental and computational investigations have been conducted in this study to assess the influence of municipal waste pyrolyzed biochar impregnated clay composites on antibiotic removal as a material for wastewater treatment and simultaneous value-addition for waste. The surface potential (zeta potential) of the pristine biochar and composite...

Biosolids produced at wastewater treatment facilities are extensively used in agricultural land and degraded mine sites to improve soil health and soil organic carbon (SOC) stocks. Many studies have reported increases in SOC due to application of biosolids to such sites. However, lack of a comprehensive quantification on overall trends and changes...

Swine and chicken manures are abundant solid wastes that can be converted into carbonaceous materials through hydrothermal carbonization (HTC). Owing to their unique biochemical compositions, co-HTC of these two types of manures may have significant implications for the generated products. We investigated the co-HTC of swine manure and chicken manu...

The discovery of anammox process has provided eco-friendly and low-cost means of treating ammonia rich wastewater with remarkable efficiency. Furthermore, recent studies have shown that the possibility of operating the anammox process under low temperatures and high organic matter contents broadening the application of the anammox process. However,...

South Asian countries have been experiencing frequent drought incidents recently, and due to this reason, many scientific studies have been carried out to explore drought in South Asia. In this context, we review scientific studies related to drought in South Asia. The study initially identifies the importance of drought-related studies and discuss...

Weathering of microplastics (MPs, < 5 mm) in terrestrial and aquatic environments affects MP transport and distribution. This paper first summarizes the sources of MPs, including refuse in landfills, biowastes, plastic films, and wastewater discharge. Once MPs enter water and soil, they undergo different weathering processes. MPs can be converted i...

South Asian countries experience frequent drought incidents recently, and due to this reason, many scientific studies were carried to explore the drought in South Asia. In this context, we review scientific studies related to drought in South Asia. The study initially identifies the importance of drought-related studies and discusses drought types...

The goal of the present study was to evaluate the immobilization and retention of caffeine (CFN) in soil and the influence of biochar for the CFN transport in agricultural soil. The biochar was produced from the Ulva reticulata seaweed biomass (ULBC) under the slow-pyrolysis with a heating rate of 7 °C/min at 500 °C and characterized using XRD and...

Arsenic (As), a geogenic and extremely toxic metalloid can jeopardize terrestrial and aquatic ecosystems through environmental partitioning in natural soil-water compartment, geothermal and marine environments. Although, many researchers have investigated the decontamination potential of different mesoporous engineered bio sorbents for a suite of c...