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  1. Fulltext A discussion of microplastics in soil and risks for ecosystems and food chains
    Li Z, Yang Y, Chen X, He Y, Bolan N, Rinklebe J, et al.
    Chemosphere, 2023 Feb;313:137637.
    PMID: 36572363 DOI: 10.1016/j.chemosphere.2022.137637
    Microplastics are among the major contaminations in terrestrial and marine environments worldwide. These persistent organic contaminants composed of tiny particles are of concern due to their potential hazards to ecosystem and human health. Microplastics accumulates in the ocean and in terrestrial ecosystems, exerting effects on living organisms including microbiomes, fish and plants. While the accumulation and fate of microplastics in marine ecosystems is thoroughly studied, the distribution and biological effects in terrestrial soil call for more research. Here, we review the sources of microplastics and its effects on soil physical and chemical properties, including water holding capacity, bulk density, pH value as well as the potential effects to microorganisms and animals. In addition, we discuss the effects of microplastics in combination with other toxic environmental contaminants including heavy metals and antibiotics on plant growth and physiology, as well as human health and possible degradation and remediation methods. This reflect is an urgent need for monitoring projects that assess the toxicity of microplastics in soil and plants in various soil environments. The prospect of these future research activities should prioritize microplastics in agro-ecosystems, focusing on microbial degradation for remediation purposes of microplastics in the environment.
  2. A recent global review of hazardous chlorpyrifos pesticide in fruit and vegetables: Prevalence, remediation and actions needed
    Foong SY, Ma NL, Lam SS, Peng W, Low F, Lee BHK, et al.
    J Hazard Mater, 2020 Dec 05;400:123006.
    PMID: 32947729 DOI: 10.1016/j.jhazmat.2020.123006
    Pollution with pesticides is a widespread global problem and biomonitoring of the environment and human populations is necessary to assess potential harmful biological effects. One of the pesticides that are showing up in vegetables and fruit is chlorpyrifos (CPS). CPS is a nerve-poisoning organophosphorus insecticide, which is in up to 1/3 of all conventionally produced citrus fruits. Our review shows that CPS is a hazardous material that poses risks to human health and also pollutes the environment. There is numerous risk assessment of CPS reported, however, the assessment is easily affected by factors such as climate change, exposure period and CPS concentration. Therefore, rigorous update of the hazardous level of CPS is needed to determine the threshold level safe for humans and animals. There is a need for remediation using for example photoreactive nanoparticle methods and microbial degeneration possessing high degradation efficiency (73-97%). In addition, stringent biomonitoring of food, environment and human exposure should occur to avoid exposure to chemicals via citrus fruits and vegetables. This is necessary to assess health risks and socioeconomic impacts which also require collaboration between private and public sectors to facilitate the growth, sale and manufacturing of biopesticides.
  3. A review of dietary phytochemicals and their relation to oxidative stress and human diseases
    Guan R, Van Le Q, Yang H, Zhang D, Gu H, Yang Y, et al.
    Chemosphere, 2021 May;271:129499.
    PMID: 33445014 DOI: 10.1016/j.chemosphere.2020.129499
    Phytochemicals refer to active substances in plant-based diets. Phytochemicals found in for example fruits, vegetables, grains and seed oils are considered relatively safe for consumption due to mammal-plant co-evolution and adaptation. A number of human diseases are related to oxidative stress caused by for example chemical environmental contaminants in air, water and food; while also lifestyle including smoking and lack of exercise and dietary preferences are important factors for disease development in humans. Here we explore the dietary sources of antioxidant phytochemicals that have beneficial effects on oxidative stress, cardiovascular and neurological diseases as well as cancer. Plant-based diets usually contain phenolic acids, flavonoids and carotenoids, which have strong antioxidant properties, and therefore remove the excess of active oxygen in the body, and protect cells from damage, reducing the risk of cardiovascular and Alzheimer's disease. In most cases, obesity is related to diet and inactivity and plant-based diets change lipid composition and metabolism, which reduce obesity related hazards. Cruciferous and Allium vegetables are rich in organic sulphides that can act on the metabolism of carcinogens and therefore used as anti-cancer and suppressing agents while dietary fibres and plant sterols may improve intestinal health and prevent intestinal diseases. Thus, we recommend a diet rich in fruits, vegetables, and grains as its content of phytochemicals may have the potential to prevent or improve a broad sweep of various diseases.
  4. A review of historical and recent locust outbreaks: Links to global warming, food security and mitigation strategies
    Peng W, Ma NL, Zhang D, Zhou Q, Yue X, Khoo SC, et al.
    Environ Res, 2020 12;191:110046.
    PMID: 32841638 DOI: 10.1016/j.envres.2020.110046
    Locusts differ from ordinary grasshoppers in their ability to swarm over long distances and are among the oldest migratory pests. The ecology and biology of locusts make them among the most devastating pests worldwide and hence the calls for actions to prevent the next outbreaks. The most destructive of all locust species is the desert locust (Schistocerca gregaria). Here, we review the current locust epidemic 2020 outbreak and its causes and prevention including the green technologies that may provide a reference for future directions of locust control and food security. Massive locust outbreaks threaten the terrestrial environments and crop production in around 100 countries of which Ethiopia, Somalia and Kenya are the most affected. Six large locust outbreaks are reported for the period from 1912 to 1989 all being closely related to long-term droughts and warm winters coupled with occurrence of high precipitation in spring and summer. The outbreaks in East Africa, India and Pakistan are the most pronounced with locusts migrating more than 150 km/day during which the locusts consume food equivalent to their own body weight on a daily basis. The plague heavily affects the agricultural sectors, which is the foundation of national economies and social stability. Global warming is likely the main cause of locust plague outbreak in recent decades driving egg spawning of up to 2-400,000 eggs per square meter. Biological control techniques such as microorganisms, insects and birds help to reduce the outbreaks while reducing ecosystem and agricultural impacts. In addition, green technologies such as light and sound stimulation seem to work, however, these are challenging and need further technological development incorporating remote sensing and modelling before they are applicable on large-scales. According to the Food and Agriculture Organization (FAO) of the United Nations, the 2020 locust outbreak is the worst in 70 years probably triggered by climate change, hurricanes and heavy rain and has affected a total of 70,000 ha in Somalia and Ethiopia. There is a need for shifting towards soybean, rape, and watermelon which seems to help to prevent locust outbreaks and obtain food security. Furthermore, locusts have a very high protein content and is an excellent protein source for meat production and as an alternative human protein source, which should be used to mitigate food security. In addition, forestation of arable land improves local climate conditions towards less precipitation and lower temperatures while simultaneously attracting a larger number of birds thereby increasing the locust predation rates.
  5. A review on phytoremediation of contaminants in air, water and soil
    Wei Z, Van Le Q, Peng W, Yang Y, Yang H, Gu H, et al.
    J Hazard Mater, 2021 02 05;403:123658.
    PMID: 33264867 DOI: 10.1016/j.jhazmat.2020.123658
    There is a global need to use plants to restore the ecological environment. There is no systematic review of phytoremediation mechanisms and the parameters for environmental pollution. Here, we review this situation and describe the purification rate of different plants for different pollutants, as well as methods to improve the purification rate of plants. This is needed to promote the use of plants to restore the ecosystems and the environment. We found that plants mainly use their own metabolism including the interaction with microorganisms to repair their ecological environment. In the process of remediation, the purification factors of plants are affected by many conditions such as light intensity, stomatal conductance, temperature and microbial species. In addition the efficiency of phytoremediation is depending on the plants species-specific metabolism including air absorption and photosynthesis, diversity of soil microorganisms and heavy metal uptake. Although the use of nanomaterials and compost promote the restoration of plants to the environment, a high dose may have negative impacts on the plants. In order to improve the practicability of the phytoremediation on environmental restoration, further research is needed to study the effects of different kinds of catalysts on the efficiency of phytoremediation. Thus, the present review provides a recent update for development and applications of phytoremediation in different environments including air, water, and soil.
  6. A review on valorization of oyster mushroom and waste generated in the mushroom cultivation industry
    Wan Mahari WA, Peng W, Nam WL, Yang H, Lee XY, Lee YK, et al.
    J Hazard Mater, 2020 12 05;400:123156.
    PMID: 32574879 DOI: 10.1016/j.jhazmat.2020.123156
    A review of valorization of oyster mushroom species and waste generated in the mushroom cultivation is presented, with a focus on the cultivation and valorization techniques, conditions, current research status and particularly the hazard mitigation and value-added recovery of the waste mushroom substrate (WMS) - an abundant waste in mushroom cultivation industry. Based on the studies reviewed, the production rate of the present mushroom industry is inadequate to meet market demands. There is a need for the development of new mushroom cultivation methods that can guarantee an increase in mushroom productivity and quality (nutritional and medicinal properties). This review shows that the cylindrical baglog cultivation method is more advantageous compared with the wood tray cultivation method to improve the mushroom yield and cost efficiency. Approximately 5 kg of potentially hazardous WMS (spreading diseases in mushroom farm) is generated for production of 1 kg of mushroom. This encourages various valorization of WMS for use in agricultural and energy conversion applications, mainly as biocompost, plant growing media, and bioenergy. The use of WMS as biofertilizer has shown desirable performance compared to conventional chemical fertilizer, whilst the use of WMS as energy feedstock could produce cleaner bioenergy sources compared to conventional fuels.
  7. A state-of-the-art review on producing engineered biochar from shellfish waste and its application in aquaculture wastewater treatment
    Wan Mahari WA, Waiho K, Azwar E, Fazhan H, Peng W, Ishak SD, et al.
    Chemosphere, 2022 Feb;288(Pt 2):132559.
    PMID: 34655643 DOI: 10.1016/j.chemosphere.2021.132559
    Global production of shellfish aquaculture is steadily increasing owing to the growing market demands for shellfish. The intensification of shellfish aquaculture to maximize production rate has led to increased generation of aquaculture waste streams, particularly the effluents and shellfish wastes. If not effectively managed, these wastes could pose serious threats to human health and the ecosystem while compromising the overall sustainability of the industry. The present work comprehensively reviews the source, composition, and environmental implications of shellfish wastes and aquaculture wastewater. Moreover, recent advancements in the valorization of shellfish wastes into value-added biochar via emerging thermochemical and modification techniques are scrutinized. The utilization of the produced biochar in removing emerging pollutants from aquaculture wastewater is also discussed. It was revealed that shellfish waste-derived biochar exhibits relatively higher adsorption capacities (300-1500 mg/g) compared to lignocellulose biochar (<200 mg/g). The shellfish waste-derived biochar can be effectively employed for the removal of various contaminants such as antibiotics, heavy metals, and excessive nutrients from aquaculture wastewater. Finally, future research priorities and challenges faced to improve the sustainability of the shellfish aquaculture industry to effectively support global food security are elaborated. This review envisages that future studies should focus on the biorefinery concept to extract more useful compounds (e.g., carotenoid, chitin) from shellfish wastes for promoting environmental-friendly aquaculture.
  8. A strategy for bioremediation of nuclear contaminants in the environment
    Li Z, He Y, Sonne C, Lam SS, Kirkham MB, Bolan N, et al.
    Environ Pollut, 2023 Feb 15;319:120964.
    PMID: 36584860 DOI: 10.1016/j.envpol.2022.120964
    Radionuclides released from nuclear contamination harm the environment and human health. Nuclear pollution spread over large areas and the costs associated with decontamination is high. Traditional remediation methods include both chemical and physical, however, these are expensive and unsuitable for large-scale restoration. Bioremediation is the use of plants or microorganisms to remove pollutants from the environment having a lower cost and can be upscaled to eliminate contamination from soil, water and air. It is a cheap, efficient, ecologically, and friendly restoration technology. Here we review the sources of radionuclides, bioremediation methods, mechanisms of plant resistance to radionuclides and the effects on the efficiency of biological adsorption. Uptake of radionuclides by plants can be facilitated by the addition of appropriate chemical accelerators and agronomic management, such as citric acid and intercropping. Future research should accelerate the use of genetic engineering and breeding techniques to screen high-enrichment plants. In addition, field experiments should be carried out to ensure that this technology can be applied to the remediation of nuclear contaminated sites as soon as possible.
  9. Applying microwave vacuum pyrolysis to design moisture retention and pH neutralizing palm kernel shell biochar for mushroom production
    Wan Mahari WA, Nam WL, Sonne C, Peng W, Phang XY, Liew RK, et al.
    Bioresour Technol, 2020 Sep;312:123572.
    PMID: 32470829 DOI: 10.1016/j.biortech.2020.123572
    Microwave vacuum pyrolysis of palm kernel shell was examined to produce engineered biochar for application as additive in agriculture application. The pyrolysis approach, performed at 750 W of microwave power, produced higher yield of porous biochar (28 wt%) with high surface area (270 cm2/g) compared to the yield obtained by conventional approach (<23 wt%). Addition of the porous biochar in mushroom substrate showed increased moisture content (99%) compared to the substrate without biochar (96%). The mushroom substrate added with biochar (150 g) was optimal in shortening formation, growth, and full colonization of the mycelium within one month. Using 2.5% of the biochar in mushroom substrate desirably maintained the optimum pH level (6.8-7) during the mycelium colonization period, leading to high mycelium growth (up to 91%) and mushroom yield (up to 280 g). The engineered biochar shows great potential as moisture retention and neutralizing agent in mushroom cultivation.
  10. Fulltext Body mass, mercury exposure, biochemistry and untargeted metabolomics of incubating common eiders (Somateria mollissima) in three Baltic colonies
    Ma NL, Hansen M, Roland Therkildsen O, Kjær Christensen T, Skjold Tjørnløv R, Garbus SE, et al.
    Environ Int, 2020 09;142:105866.
    PMID: 32590281 DOI: 10.1016/j.envint.2020.105866
    The Baltic/Wadden Sea Flyway of common eiders has declined over the past three decades. Multiple factors such as contaminant exposure, global warming, hunting, white-tailed eagle predation, decreased agricultural eutrophication and infectious diseases have been suggested to explain the decline. We collected information on body mass, mercury (Hg) concentration, biochemistry and untargeted metabolomics of incubating birds in two colonies in the Danish Straits (Hov Røn, n = 100; Agersø, n = 29) and in one colony in the Baltic proper (Christiansø, n = 23) to look into their metabolisms and energy balance. Body mass was available from early and late incubation for Hov Røn and Christiansø, showing a significant decline (25-30%) in both colonies with late body mass at Christiansø being the lowest. Whole blood concentrations of total mercury Hg were significantly higher in birds at Christiansø in the east compared to Hov Røn in the west. All birds in the three colonies had Hg concentrations in the range of ≤1.0 μg/g ww, which indicates that the risk of effects on reproduction is in the no to low risk category for wild birds. Among the biochemical measures, glucose, fructosamine, amylase, albumin and protein decreased significantly from early to late incubation at Hov Røn and Christiansø, reflecting long-term fastening as supported by the decline in body mass. Untargeted metabolomics performed on Christiansø eiders revealed presence of 8,433 plasma metabolites. Of these, 3,179 metabolites changed significantly (log2-fold change ≥1, p ≤ 0.05) from the early to late incubation. For example, smaller peptides and vitamin B2 (riboflavin) were significantly down-regulated while 11-deoxycorticosterone and palmitoylcarnitine were significantly upregulated. These results show that cumulative stress including fasting during incubation affect the eiders' biochemical profile and energy metabolism and that this may be most pronounced for the Christiansø colony in the Baltic proper. This amplify the events of temperature increases and food web changes caused by global warming that eventually accelerate the loss in body weight. Future studies should examine the relationship between body condition, temperature and reproductive outcomes and include mapping of food web contaminant, energy and nutrient content to better understand, manage and conserve the populations.
  11. Cervicograms of normal labour in Malaysian women
    Peng WW, Aun LM, Sinnathuray TA, Lin WM
    Med J Malaysia, 1976 Jun;30(4):261-3.
    PMID: 979726
  12. Comparison of shrimp waste-derived chitosan produced through conventional and microwave-assisted extraction processes: Physicochemical properties and antibacterial activity assessment
    Mohammadi P, Taghavi E, Foong SY, Rajaei A, Amiri H, de Tender C, et al.
    Int J Biol Macromol, 2023 Jul 01;242(Pt 2):124841.
    PMID: 37182628 DOI: 10.1016/j.ijbiomac.2023.124841
    Depending on its physicochemical properties and antibacterial activities, chitosan can have a wide range of applications in food, pharmaceutical, medicine, cosmetics, agriculture, and aquaculture. In this experimental study, chitosan was extracted from shrimp waste through conventional extraction, microwave-assisted extraction, and conventional extraction under microwave process conditions. The effects of the heating source on the physicochemical properties and antibacterial activity were investigated. The results showed that the heating process parameters affected the physicochemical properties considerably. The conventional procedure yielded high molecular weight chitosan with a 12.7 % yield, while the microwave extraction procedure yielded a porous medium molecular weight chitosan at 11.8 %. The conventional extraction under microwave process conditions led to medium molecular weight chitosan with the lowest yield (10.8 %) and crystallinity index (79 %). Antibacterial assessment findings revealed that the chitosan extracted using the conventional method had the best antibacterial activity in the agar disk diffusion assay against Listeria monocytogenes (9.48 mm), Escherichia coli. (8.79 mm), and Salmonella Typhimurium (8.57 mm). While the chitosan obtained by microwave-assisted extraction possessed the highest activity against E. coli. (8.37 mm), and Staphylococcus aureus (8.05 mm), with comparable antibacterial activity against S. Typhimurium (7.34 mm) and L. monocytogenes (6.52 mm). Moreover, the minimal inhibitory concentration and minimal bactericidal concentration assays demonstrated that among the chitosan samples investigated, the conventionally-extracted chitosan, followed by the chitosan extracted by microwave, had the best antibacterial activity against the target bacteria.
  13. Fulltext Covid-19 pandemic in the lens of food safety and security
    Ma NL, Peng W, Soon CF, Noor Hassim MF, Misbah S, Rahmat Z, et al.
    Environ Res, 2021 Feb;193:110405.
    PMID: 33130165 DOI: 10.1016/j.envres.2020.110405
    The recently emerged coronavirus disease (COVID-19), which has been characterised as a pandemic by the World Health Organization (WHO), is impacting all parts of human society including agriculture, manufacturing, and tertiary sectors involving all service provision industries. This paper aims to give an overview of potential host reservoirs that could cause pandemic outbreak caused by zoonotic transmission. Amongst all, continues surveillance in slaughterhouse for possible pathogens transmission is needed to prevent next pandemic outbreak. This paper also summarizes the potential threats of pandemic to agriculture and aquaculture sector that control almost the total food supply chain and market. The history lesson from the past, emerging and reemerging infectious disease including the Severe Acute Respiratory Syndrome (SARS) in 2002, Influenza A H1N1 (swine flu) in 2009, Middle East Respiratory Syndrome (MERS) in 2012 and the recent COVID-19 should give us some clue to improve especially the governance to be more ready for next coming pandemic.
  14. Current and emerging applications of saccharide-modified chitosan: a critical review
    Kazemi Shariat Panahi H, Dehhaghi M, Amiri H, Guillemin GJ, Gupta VK, Rajaei A, et al.
    Biotechnol Adv, 2023 Sep;66:108172.
    PMID: 37169103 DOI: 10.1016/j.biotechadv.2023.108172
    Chitin, as the main component of the exoskeleton of Arthropoda, is a highly available natural polymer that can be processed into various value-added products. Its most important derivative, i.e., chitosan, comprising β-1,4-linked 2-amino-2-deoxy-β-d-glucose (deacetylated d-glucosamine) and N-acetyl-d-glucosamine units, can be prepared via alkaline deacetylation process. Chitosan has been used as a biodegradable, biocompatible, non-antigenic, and nontoxic polymer in some in-vitro applications, but the recently found potentials of chitosan for in-vivo applications based on its biological activities, especially antimicrobial, antioxidant, and anticancer activities, have upgraded the chitosan roles in biomaterials. Chitosan approval, generally recognized as a safe compound by the United States Food and Drug Administration, has attracted much attention toward its possible applications in diverse fields, especially biomedicine and agriculture. Despite some favorable characteristics, the chitosan's structure should be customized for advanced applications, especially due to its drawbacks, such as low drug-load capacity, low solubility, high viscosity, lack of elastic properties, and pH sensitivity. In this context, derivatization with relatively inexpensive and highly available mono- and di-saccharides to soluble branched chitosan has been considered a "game changer". This review critically scrutinizes the emerging technologies based on the synthesis and application of lactose- and galactose-modified chitosan as two important chitosan derivatives. Some characteristics of chitosan derivatives and biological activities have been detailed first to understand the value of these natural polymers. Second, the saccharide modification of chitosan has been discussed briefly. Finally, the applications of lactose- and galactose-modified chitosan have been scrutinized and compared to native chitosan to provide an insight into the current state-of-the research for stimulating new ideas with the potential of filling research gaps.
  15. Deforestation of rainforests requires active use of UN's Sustainable Development Goals
    Wan Mahari WA, Azwar E, Li Y, Wang Y, Peng W, Ma NL, et al.
    Sci Total Environ, 2020 Nov 10;742:140681.
    PMID: 33167298 DOI: 10.1016/j.scitotenv.2020.140681
    The deforestation and burning of the Amazon and other rainforests is having a cascade of effects on global climate, biodiversity, human health and local and regional socioeconomics. This challenging situation demands a sustainable exploitation of the region's resources in accordance with the United Nations (UNs) Sustainable Development Goals (SDGs) in order to meet Good Environmental Status and reduce poverty. The management of forests sustainability spans across at least eight of the 17 UN SDGs mainly to combat desertification, halt biodiversity loss, and reverse land degradation. Significant changes are needed if we are to sustain the world's rainforests and thereby the global climate and biodiversity. These measures and mitigations are of global responsibility requiring both developed and developing nations such as the United States, EU, and China to change their policies and stand regarding their high demand for meat and hardwood. When possible, non-profit tree-planting internet browsers should be implemented by governments and institutions. So far, there is a lack of active use of the UN SDGs and the countries must therefore need to fully adopt the UN SDGs in order to help the situation. One way to enforce this could be through imposing economic penalties to governments and national institutions that do not adhere to for example publishing open access of data and other important information relevant for the mission of the UN SDGs.
  16. Design, preparation and evaluation of a high performance sensor for formaldehyde based on a novel hybride nonocomposite ZnWO3/rGO
    Ashraf MA, Liu Z, Peng W, Parsaee Z
    Anal Chim Acta, 2019 Mar 21;1051:120-128.
    PMID: 30661608 DOI: 10.1016/j.aca.2018.11.014
    The ultrasound wave assisted synthesis of a novel ZnWO3/rGO hybrid nono composition (ZnWO3/rGO HNC) as a high performance sensor for formaldehyde (FA) has been reported. Different techniques of analysis such as XRD, FE-SEM, TGA, XPS, HRTEM and BET were applied for morphological and spectroscopic characterization of the ZnWO3/rGO HNC. The sensing evaluation of the constructed sensor showed high selectivity, sensitivity and a linear correlation between achieved responses and concentration of target gas (1-10 ppm) with R2 = 0.993 at temperature of 95 °C. The determination of FA was validated and performed using gas chromatography-mass spectrometry combined by solid phase micro-extraction after derivatization with O-(2,3,4,5,6-pentafluoro-benzyl)-hydroxylamine hydrochloride. Validation was carried out in terms of limit of detection linearity, precision, and recovery. The mechanistic evaluation of sensing behavior of the ZnWO3/rGO HNC was interpreted based on large specific surface area (SSA) to volume, mesoporous structure and the heterojunction between rGO and ZnWO3 at the interface between the rGO and ZnWO3.
  17. Driving sustainable circular economy in electronics: A comprehensive review on environmental life cycle assessment of e-waste recycling
    He Y, Kiehbadroudinezhad M, Hosseinzadeh-Bandbafha H, Gupta VK, Peng W, Lam SS, et al.
    Environ Pollut, 2024 Feb 01;342:123081.
    PMID: 38072018 DOI: 10.1016/j.envpol.2023.123081
    E-waste, encompassing discarded materials from outdated electronic equipment, often ends up intermixed with municipal solid waste, leading to improper disposal through burial and incineration. This improper handling releases hazardous substances into water, soil, and air, posing significant risks to ecosystems and human health, ultimately entering the food chain and water supply. Formal e-waste recycling, guided by circular economy models and zero-discharge principles, offers potential solutions to this critical challenge. However, implementing a circular economy for e-waste management due to chemical and energy consumption may cause environmental impacts. Consequently, advanced sustainability assessment tools, such as Life Cycle Assessment (LCA), have been applied to investigate e-waste management strategies. While LCA is a standardized methodology, researchers have employed various routes for environmental assessment of different e-waste management methods. However, to the authors' knowledge, there lacks a comprehensive study focusing on LCA studies to discern the opportunities and limitations of this method in formal e-waste management strategies. Hence, this review aims to survey the existing literature on the LCA of e-waste management under a circular economy, shedding light on the current state of research, identifying research gaps, and proposing future research directions. It first explains various methods of managing e-waste in the circular economy. This review then evaluates and scrutinizes the LCA approach in implementing the circular bioeconomy for e-waste management. Finally, it proposes frameworks and procedures to enhance the applicability of the LCA method to future e-waste management research. The literature on the LCA of e-waste management reveals a wide variation in implementing LCA in formal e-waste management, resulting in diverse results and findings in this field. This paper underscores that LCA can pinpoint the environmental hotspots for various pathways of formal e-waste recycling, particularly focusing on metals. It can help address these concerns and achieve greater sustainability in e-waste recycling, especially in pyrometallurgical and hydrometallurgical pathways. The recovery of high-value metals is more environmentally justified compared to other metals. However, biometallurgical pathways remain limited in terms of environmental studies. Despite the potential for recycling e-waste into plastic or glass, there is a dearth of robust background in LCA studies within this sector. This review concludes that LCA can offer valuable insights for decision-making and policy processes on e-waste management, promoting environmentally sound e-waste recycling practices. However, the accuracy of LCA results in e-waste recycling, owing to data requirements, subjectivity, impact category weighting, and other factors, remains debatable, emphasizing the need for more uncertainty analysis in this field.
  18. Effect of carnosine supplementation on lipid profile, fasting blood glucose, HbA1C and insulin resistance: A systematic review and meta-analysis of long-term randomized controlled trials
    Peng W, Mao P, Liu L, Chen K, Zhong Y, Xia W, et al.
    Complement Ther Med, 2020 Jan;48:102241.
    PMID: 31987255 DOI: 10.1016/j.ctim.2019.102241
    OBJECTIVE: Glucose disorders and dyslipidemia are closely associated with obesity and metabolic disease. The purpose of this study was to investigate the effect of Carnosine supplementation on lipid profile, fasting blood glucose, HbA1C and Insulin resistance.

    METHOD: MEDLINE/PubMed, Scopus and Web of sciences were investigated to identify relevant articles up to June 2019. The search strategy combined the Medical Subject Heading and Title and/or abstract keywords. The combined effect sizes were calculated as weight mean difference (WMD) using the random-effects model. Between study heterogeneity was evaluated by the Cochran's Q test and I2.

    RESULTS: Four RCTs studies investigated Carnosine use versus any control for at least 2 weeks were identified and analyzed. Overall results from the random-effects model on included studies, with 184 participants, indicated that carnosine intervention reduced HbA1C levels in intervention vs control groups (WMD: -0.92 %, 95 % CI: -1.20, -0.63, I2:69 %). Four studies, including a total of 183 participants, reported TG changes as an outcome measure variable, but combined results did not show significant reduction in this outcome (WMD: -14.46 mg/dl, 95 % CI: -29.11, 0.19, I2:94 %). Furthermore, combined results did not show any significant change in HOMA-IR, Cholesterol, fasting blood sugar, or HDL-C.

    CONCLUSION: Carnosine supplementation results in a decrease in HbA1C, but elicits no effect on HOMA-IR, Cholesterol, fasting blood sugar, TG and HDL-C. Future studies with a larger sample sizes, varied doses of carnosine, and population-specific sub-groups are warranted to confirm, and enhance, the veracity of our findings.

  19. Fulltext Effects of Size and Aggregation/Agglomeration of Nanoparticles on the Interfacial/Interphase Properties and Tensile Strength of Polymer Nanocomposites
    Ashraf MA, Peng W, Zare Y, Rhee KY
    Nanoscale Res Lett, 2018 Jul 17;13(1):214.
    PMID: 30019092 DOI: 10.1186/s11671-018-2624-0
    In this study, several simple equations are suggested to investigate the effects of size and density on the number, surface area, stiffening efficiency, and specific surface area of nanoparticles in polymer nanocomposites. In addition, the roles of nanoparticle size and interphase thickness in the interfacial/interphase properties and tensile strength of nanocomposites are explained by various equations. The aggregates/agglomerates of nanoparticles are also assumed as large particles in nanocomposites, and their influences on the nanoparticle characteristics, interface/interphase properties, and tensile strength are discussed. The small size advantageously affects the number, surface area, stiffening efficiency, and specific surface area of nanoparticles. Only 2 g of isolated and well-dispersed nanoparticles with radius of 10 nm (R = 10 nm) and density of 2 g/cm3 produce the significant interfacial area of 250 m2 with polymer matrix. Moreover, only a thick interphase cannot produce high interfacial/interphase parameters and significant mechanical properties in nanocomposites because the filler size and aggregates/agglomerates also control these terms. It is found that a thick interphase (t = 25 nm) surrounding the big nanoparticles (R = 50 nm) only improves the B interphase parameter to about 4, while B = 13 is obtained by the smallest nanoparticles and the thickest interphase.
  20. Engineered biochar via microwave CO2 and steam pyrolysis to treat carcinogenic Congo red dye
    Yek PNY, Peng W, Wong CC, Liew RK, Ho YL, Wan Mahari WA, et al.
    J Hazard Mater, 2020 08 05;395:122636.
    PMID: 32298946 DOI: 10.1016/j.jhazmat.2020.122636
    We developed an innovative single-step pyrolysis approach that combines microwave heating and activation by CO2 or steam to transform orange peel waste (OPW) into microwave activated biochar (MAB). This involves carbonization and activation simultaneously under an inert environment. Using CO2 demonstrates dual functions in this approach, acting as purging gas to provide an inert environment for pyrolysis while activating highly porous MAB. This approach demonstrates rapid heating rate (15-120 °C/min), higher temperature (> 800 °C) and shorter process time (15 min) compared to conventional method using furnace (> 1 h). The MAB shows higher mass yield (31-44 wt %), high content of fixed carbon (58.6-61.2 wt %), Brunauer Emmett Teller (BET) surface area (158.5-305.1 m2/g), low ratio of H/C (0.3) and O/C (0.2). Activation with CO2 produces more micropores than using steam that generates more mesopores. Steam-activated MAB records a higher adsorption efficiency (136 mg/g) compared to CO2 activation (91 mg/g), achieving 89-93 % removal of Congo Red dye. The microwave pyrolysis coupled with steam or CO2 activation thereby represents a promising approach to transform fruit-peel waste to microwave-activated biochar that remove hazardous dye.
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