Asteraceae presents one of the most globally prevalent, cultivated, and fundamental plant families. However, a large amount of agricultural wastes has been yearly released from Asteraceae crops, causing adverse impacts on the environment. The objective of this work is to have insights into their biomass potentials and technical possibility of conversion into biochars. Physicochemical properties are systematically articulated to orientate environmental application, soil amendment, and other utilizations. Utilizations of Asteraceae biochars in wastewater treatment can be categorized by heavy metal ions, organic dyes, antibiotics, persistent organic pollutants (POPs), and explosive compounds. Some efforts were made to analyze the production cost, as well as the challenges and prospects of Asteraceae-based biochars.
Above 1000 invasive species have been growing and developing ubiquitously on Earth. With extremely vigorous adaptability, strong reproduction, and spreading powers, invasive species have posed an alarming threat to indigenous plants, water quality, soil, as well as biodiversity. It was estimated that an economic loss of billions of dollars or equivalent to 1 % of gross domestic product as a consequence of lost crops, control efforts, and damage costs caused by invasive plants in the United States. While eradicating invasive plants from the ecosystems is practically infeasible, taking advantage of invasive plants as a sustainable, locally available, and zero-cost source to provide valuable phytochemicals for bionanoparticles fabrication is worth considering. Here, we review the harms, benefits, and role of invasive species as important botanical sources to extract natural compounds such as piceatannol, resveratrol, and quadrangularin-A, flavonoids, and triterpenoids, which are linked tightly to the formation and application of bionanoparticles. As expected, the invasive plant-mediated bionanoparticles have exhibited outstanding antibacterial, antifungal, anticancer, and antioxidant activities. The mechanism of biomedical activities of the invasive plant-mediated bionanoparticles was insightfully addressed and discussed. We also expect that this review not only contributes to efforts to combat invasive plant species but also opens new frontiers of bionanoparticles in the biomedical applications, therapeutic treatment, and smart agriculture.
The speciation patterns of Cu, Cd, Zn, Pb, Fe and Mn in sediment samples under anoxic and oxidized conditions were investigated using three-stage, four-stage and five-stage sequential extraction schemes. All the extraction schemes identify the non-residual metal among three basic operationally-defined host fractions, namely, exchangeable, reducible and organic/sulfide bound. The anoxic sediment samples were found to have been oxidized during the extraction stage for the reducible fraction under the three-stage and four-stage schemes and the moderately reducible fraction under the five-stage scheme despite the maintenance of an oxygen-free environment. This artifact has resulted in an over-representation of the reducible fraction and an under-representation of the organic/sulfide fraction in the heavy metal speciation patterns of anoxic sediment samples. For Cd, Zn and Pb which had > 70% associated with the acid volatile sulfide in the organic/sulfide fraction, this artifact has resulted in the observation of a decrease in the reducible fraction and, in some cases, an increase in the organic/sulfide fraction upon oxidation of the anoxic sediment samples.
An effective drought monitoring tool is essential for the development of timely drought early warning system. This study evaluates Evaporative Demand Drought Index (EDDI) as a drought indicator in measuring spatiotemporal evolution of droughts over Peninsular Malaysia during 1989-2018. The modified Mann-Kendall and Sen's slope tests were performed to detect the presence of monotonic trends in EDDI, Standardized Precipitation Index (SPI), Standardized Precipitation Evapotranspiration Index (SPEI) and their related climate variables. The performance of EDDI in capturing the drought onset, evolutions and demise of historical severe droughts was also compared with SPI and SPEI at multiple timescales. EDDI demonstrates strong spatiotemporal correlations with SPI and SPEI and comparable performance in historical drought events identification. At sub-monthly timescale, 2-week EDDI displays equivalent drought severities and durations for all historical severe droughts corresponding to the monthly EDDI. In the case when rainfall deficits are normalized in an otherwise warm and dry month, EDDI may serve as a great alternative to SPI and SPEI due to it being sensitive to the changes in prevalent atmospheric conditions. Collectively, the results fill in the knowledge gaps on drought evolutions from the evaporative perspective and highlight the efficacy of EDDI as a valuable drought early warning tool for Peninsular Malaysia. Future study should explore the physical mechanisms behind the development of flash drought and the role of evaporation in the drought propagation processes.
The quantification of microplastics in environmental samples often requires an observer to determine whether a particle is plastic or non-plastic, prior to further verification procedures. This implies that inconspicuous microplastics with a low natural detection may be underestimated. The present study aimed at assessing this underestimation, looking at how colour (white, green and blue), size (large; ~1000 μm and small; <400 μm) and grain size fraction may affect detection. Sediment treatments varying in grain size were inoculated with known quantities of low-density polyethylene microbeads extracted from commercially bought facial scrubs. These microbeads varied in colour and size. Once extracted using a density separation method microbeads were counted. An overall underestimation of 78.59% may be a result of observer error and/or technical error. More specifically, the results suggested that microbeads varying in colour and size have a different detection probability and that these microbead features are more important in underestimation likelihoods than grain sizes.
Microplastics are important novel pollutants in freshwaters but their behaviour in river sediments is poorly understood due to the large amounts of coloured dissolved organic matter that impede sample processing. The present study aimed to 1.) estimate the microplastic pollution dynamics in an urban river system experiencing temporal differences in river flow, and 2.) investigate the potential use of chironomids as indicators of microplastic pollution levels in degraded freshwater environments. Microplastic levels were estimated from sediment and Chironomus spp. larvae collected from various sites along the Bloukrans River system, in the Eastern Cape South Africa during the summer and winter season. River flow, water depth, channel width, substrate embeddedness and sediment organic matter were simultaneously collected from each site. The winter season was characterised by elevated microplastic abundances, likely as a result of lower energy and increased sediment deposition associated with reduced river flow. In addition, results showed that particle distribution may be governed by various other external factors, such as substrate type and sediment organic matter. The study further highlighted that deposit feeders associated with the benthic river habitats, namely Chironomus spp. ingest microplastics and that the seasonal differences in sediment microplastic dynamics were reflected in chironomid microplastic abundance. There was a positive, though weakly significant relationship between deposit feeders and sediment suggesting that deposit feeders such as Chironomus spp. larvae could serve as an important indicator of microplastic loads within freshwater ecosystems.
Microwave vacuum pyrolysis of palm kernel shell (PKS) was performed to produce biochar, which was then tested as bio-fertilizer in growing Oyster mushroom (Pleurotus ostreatus). The pyrolysis approach produced biochar containing a highly porous structure with a high BET surface area of up to 270m2/g and low moisture content (≤10wt%), exhibiting desirable adsorption properties to be used as bio-fertilizer since it can act as a housing that provides many sites on which living microorganisms (mycelium or plant-growth promoting bacteria) and organic nutrients can be attached or adsorbed onto. This could in turn stimulate plant growth by increasing the availability and supply of nutrients to the targeted host plant. The results from growing Oyster mushroom using the biochar recorded an impressive growth rate and a monthly production of up to about 550g of mushroom. A shorter time for mycelium growth on one whole baglog (21days) and the highest yield of Oyster mushroom (550g) were obtained from cultivation medium added with 20g of biochar. Our results demonstrate that the biochar-based bio-fertilizer produced from microwave vacuum pyrolysis of PKS shows exceptional promise as growth promoting material for mushroom cultivation.
Polycyclic aromatic hydrocarbons (PAHs) in the atmospheric particles constitute a topic of growing health concern. This study aims to calculate PAH concentrations, identify the source, assess the health risk from exposure to carcinogenic PAHs, and the respiratory deposition flux. PM10 and PM2.5 were collected in September 2019 in the urban, semi-urban, and semi-urban-industrial areas of Kuala Lumpur, Batu Pahat, and Bukit Rambai, respectively. A total of 18 PAHs from PM10 and 17 PAHs from PM2.5 were extracted using dichloromethane and determined using gas chromatography coupled with a flame ionization detector (GC-FID). The health risk assessment (HRA) calculated included B[a]P equivalent (B[a]Peq), lifetime lung cancer risk (LLCR), incremental lifetime cancer risk (ILCR), and respiratory deposition dose (RDD). The results show PAHs in PM10 recorded in Kuala Lumpur (DBKL), Batu Pahat (UTHM), and Bukit Rambai are 9.91, 8.45, and 9.57 ng/m3, respectively. The average PAHs in PM2.5 at the three sampling sites are 11.65, 9.68, and 9.37 ng/m3, respectively. The major source of PAHs obtained from the DRs indicates pyrogenic activities for both particle sizes. For PM10, the total B[a]Peq in DBKL, UTHM, and Bukit Rambai were 1.97, 1.82, and 2.32 ng/m3, respectively. For PM2.5 samples, the total B[a]Peq in DBKL, UTHM, and Bukit Rambai were 2.80, 2.33, and 2.57 ng/m3, respectively. The LLCR and ILCR show low to moderate risk for all age groups. The RDD of adults and adolescents is highest in both PM10 and PM2.5, followed by children, toddlers, and infants. Overall, we perceive that adults and adolescents living in the urban area of Kuala Lumpur are at the highest risk for respiratory health problems because of prolonged exposure to PAHs in PM10 and PM2.5, followed by children, toddlers, and infants.
Among numerous methods developed in purification and separation industries, the adsorption process has received considerable attention due to its inexpensive, facile, and eco-friendly nature. The importance of the adsorption process causes extraordinary endeavors for modeling the adsorption isotherms during the years; thus, myriads of research have been conducted and many reviews have been published. In this paper, we have attempted to gather the most widely used adsorption isotherms and their related definitions, along with examples of correlated work of the recent decade. In the present review, 37 adsorption isotherms with about 400 references have been collected from the research published in the period of 2010-2020. The adsorption isotherms utilized are alphabetically organized for ease of access. The parameters of each isotherm, as well as the applicable definitions, are presented in the table, in addition to being discussed in the text. Another table is provided for the practical use of researchers, featuring the usage of the related isotherms in peer-reviewed studies.
Landfilling is the most widely used disposal method for municipal solid waste around the world. The main disadvantage of this strategy is 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(s) of discharging potentially harmful landfill leachate into the environment need to be assessed and measured in order to make effective choices about landfill leachate management and treatment. In view of this, the present review aims to investigate (a) how landfill leachate is perceived as an emerging concern, and (b) the stakeholders' mid- to long-term policy priorities for implementing technological and integrative solutions to reduce the harmful effects of landfill leachate. Because traditional methods alone have been reported ineffective, and in response to emerging contaminants and stringent regulations, new effective and integrated leachate treatments have been developed. This study gives a forward-thinking of the accomplishments and challenges in landfill leachate treatment during the last decade. It also provides a comprehensive compilation of the formation and characterization of landfill leachate, the geo-environmental challenges that it raises, as well as the resource recovery and industrial linkage associated with it in order to provide an insight into its sustainable management.
Exposure to secondhand smoke (SHS) can affect fetal brain development as well as subsequent neurodevelopment. This study aimed to determine the association between prenatal and postnatal SHS exposure with children's neurodevelopment at 2years of age. Among 107 mother-child pairs from a Malaysia prospective cohort, prenatal and postnatal SHS exposure was determined based on maternal and child hair nicotine concentrations. Multiple linear regressions were used to determine the association between prenatal and postnatal levels of nicotine in maternal and children's' hair with children's neurodevelopment. After adjustment for confounders, prenatal nicotine concentration levels were negatively associated with communication (β=-2.059; p=0.015) and fine motor skills (β=-2.120; p=0.002) while postnatal nicotine concentration levels were inversely associated with fine motors (β=-0.124; p=0.004) and problem solving skills (β=-0.117; p=0.013). In conclusion, this study suggests that early life exposure to SHS may affect children's neurodevelopment.
The eastern coast of India is one of the regions where most of the population resides in urban areas in the low-elevation coastal zone, making it vulnerable to frequent extreme weather events. The objectives of this study are to assess the short- to long-term shoreline changes of the Odisha coast, to understand how anthropogenic influences, and particularly extreme natural events, affect these changes, and to predict shoreline changes for 2050. This study utilized multi-temporal/spectral/spatial resolution satellite images and a digital shoreline analysis (DSAS) tool to appraise the short- (at five/six-year intervals) and long-term (1990-2019) shoreline dynamics along the coastal part of Odisha over the past three decades (1990-2019). The long-term shoreline analysis shows that the mean shoreline change is about 0.67 m/year and highlights that 52.47 % (227.4 km), 34.70 % (150.4 km), and 12.83 % (55.6 km) of the total Odisha coastline exhibit erosion, accretion, and stability, respectively. During the short-term analysis, the 2000-2005 period had the highest percentage of erosion (64.27 %), followed by the 2005-2010 period with an erosional trend of 59.06 %. The 1995-2000 period showed an accretion trend, whereas, during the last period, i.e., 2015-2019, the percentage of transects depicting erosion and accretion was almost similar. In 2050, 55.85 % of the transects are expected to show accretion, while 44.15 % would show erosion or a constant trend. The study identified the hotspots of coastal erosion along delineated study zones by synthesizing data from previous studies as well. The regional analysis of shoreline change along the Odisha coast would not only provide coastal managers with critical information on shoreline dynamics but also draw attention to vulnerable areas linked to shoreline dynamicity along the coast.
The spatial distribution of 19 polycyclic aromatic hydrocarbons (tPAHs) was quantified in aquacultures located in intertidal mudflats of the west coast of Peninsular Malaysia in order to investigate bioaccumulation of PAH in blood cockles, Anadara granosa (A. granosa). Fifty-four samples from environmental matrices and A. granosa were collected. The sampling locations were representative of a remote area as well as PAH-polluted areas. The relationship of increased background levels of PAH to anthropogenic PAH sources in the environment and their effects on bioaccumulation levels of A. granosa are investigated in this study. The levels of PAH in the most polluted station were found to be up to ten-fold higher than in remote areas in blood cockle. These high concentrations of PAHs reflected background contamination, which originates from distant airborne and waterborne transportation of contaminated particles. The fraction and source identification of PAHs, based on fate and transport considerations, showed a mix of petrogenic and pyrogenic sources. The relative biota-sediment accumulation factors (RBSAF), relative bioaccumulation factors from filtered water (RBAFw), and from suspended particulate matter (SPM) (RBAFSP) showed higher bioaccumulations of the lower molecular weight of PAHs (LMWs) in all stations, except Kuala Juru, which showed higher bioaccumulation of the higher molecular weight of PAHs (HMWs). Calculations of bioaccumulation factors showed that blood cockle can accumulate PAHs from sediment as well as water samples, based on the physico-chemical characteristics of habitat and behaviour of blood cockles. Correlations among concentrations of PAHs in water, SPM, sediment and A. granosa at the same sites were also found. Identification of PAH levels in different matrices showed that A. granosa can be used as a good biomonitor for LMW of PAHs and tPAHs in mudflats. Considering the toxicity and carcinogenicity of PAHs, the bioaccumulation by blood cockles are a potential hazard for both blood cockles and their consumers.
A study on lead exposure among school children aged between 7 and 12 years from Kajang and Sepang in the state of Selangor, Malaysia was carried out using delta-aminolevulinic acid (delta-ALA) levels in the urine as an index. The delta-ALA levels in urine were linked to variables which could contribute to lead exposure. Out of 1628 school children studied [Kajang (43.5%) and Sepang (56.5%)], only 194 subjects (16 and 8.8% from Kajang and Sepang, respectively) had urinary delta-ALA levels between 0.6 and 2.0 mg/100 ml. However, chi 2 analysis demonstrated significant association between delta-ALA of this group to some of the variables. The strongest association was found in the habit of biting fingernails (P < 0.025). Other statistically significant correlations were found between delta-ALA and father's occupation (P < 0.05) and the amount of time spent playing in the field (P < 0.01). Generally, this study indicates that school children in Kajang and Sepang are still relatively safe from excessively high lead exposure. However, a more sensitive indicator, which is based on a lower tolerable lead limits, such as lead in blood, are necessary to affirm this finding.
Carbonation for the curing of cement-based materials has been gaining increased attention in recent years, especially in light of emerging initiatives to reduce carbon dioxide (CO2) emissions. Carbonation method or CO2 curing is founded on the basis of the reaction between CO2 and cement products to form thermally stable and denser carbonate, which not only improves the physical and mechanical properties of cement-based materials, but also has the ability to utilize and store CO2 safely and permanently. This study aims to assess the effect of CO2 curing technology on the high-temperatures performance of cement blocks. Upon molding, dry-mix cement blocks were cured under statically accelerated carbonation condition (20% CO2 concentration with 70% relative humidity) for 28 days, followed by exposure to elevated temperatures of 300 °C to 800 °C in order to comprehensively study the principal phase changes and decompositions of cement hydrates. The results indicated that CO2 curing improved the performance of cement blocks, such as enhancement in the residual compressive strength and reducing the sorptivity. At 600 °C, the scanning electron microscopy (SEM) revealed a denser microstructure while thermal analisis and X-ray diffraction (XRD) analysis also clearly demonstrated that higher amounts of calcium carbonate were present in the cement blocks after CO2 curing, suggesting better high-temperature performance compared to natural cured cement blocks. In general, an improved high-temperature performance, specifically at 600 °C of the dry-mixed cement blocks was demonstrated by adopting the CO2 curing technology. This confirms the potential of utilizing CO2 curing technology in not only improving quality of cement blocks, new avenue for storing of CO2 in construction material can be realized at the same time.
While existing moratoria in Indonesia and Malaysia should preclude continued large-scale expansion of palm oil production into new areas of South-East Asian tropical peatland, existing plantations in the region remain a globally significant source of atmospheric carbon due to drainage driven decomposition of peatland soils. Previous studies have made clear the direct link between drainage depth and peat carbon decomposition and significant reductions in the emission rate of CO2 can be made by raising water tables nearer to the soil surface. However, the impact of such changes on palm fruit yield is not well understood and will be a critical consideration for plantation managers. Here we take advantage of very high frequency, long-term monitoring of canopy-scale carbon exchange at a mature oil palm plantation in Malaysian Borneo to investigate the relationship between drainage level and photosynthetic uptake and consider the confounding effects of light quality and atmospheric vapour pressure deficit. Canopy modelling from our dataset demonstrated that palms were exerting significantly greater stomatal control at deeper water table depths (WTD) and the optimum WTD for photosynthesis was found to be between 0.3 and 0.4 m below the soil surface. Raising WTD to this level, from the industry typical drainage level of 0.6 m, could increase photosynthetic uptake by 3.6 % and reduce soil surface emission of CO2 by 11 %. Our study site further showed that despite being poorly drained compared to other planting blocks at the same plantation, monthly fruit bunch yield was, on average, 14 % greater. While these results are encouraging, and at least suggest that raising WTD closer to the soil surface to reduce emissions is unlikely to produce significant yield penalties, our results are limited to a single study site and more work is urgently needed to confirm these results at other plantations.
In 2016, the World Health Organization (WHO) estimated that approximately 4.2 million premature deaths worldwide were attributable to exposure to particulate matter 2.5 μm (PM2.5). This study assessed the environmental burden of disease attributable to PM2.5 at the national level in Malaysia. We estimated the population-weighted exposure level (PWEL) of PM10 concentrations in Malaysia for 2000, 2008, and 2013 using aerosol optical density (AOD) data from publicly available remote sensing satellite data (MODIS Terra). The PWEL was then converted to PM2.5 using Malaysia's WHO ambient air conversion factor. We used AirQ+ 2.0 software to calculate all-cause (natural), ischemic heart disease (IHD), stroke, chronic obstructive pulmonary disease (COPD), lung cancer (LC), and acute lower respiratory infection (ALRI) excess deaths from the National Burden of Disease data for 2000, 2008 and 2013. The average PWELs for annual PM2.5 for 2000, 2008, and 2013 were 22 μg m-3, 18 μg m-3 and 24 μg m-3, respectively. Using the WHO 2005 Air Quality Guideline cut-off point of PM2.5 of 10 μg m-3, the estimated excess deaths for 2000, 2008, and 2013 from all-cause (natural) mortality were between 5893 and 9781 (95 % CI: 3347-12,791), COPD was between 164 and 957 (95 % CI: 95-1411), lung cancer was between 109 and 307 (95 % CI: 63-437), IHD was between 3 and 163 deaths, according to age groups (95 % CI: 2-394) and stroke was between 6 and 155 deaths, according to age groups (95 % CI: 3-261). An increase in estimated health endpoints was associated with increased estimated PWEL PM2.5 for 2013 compared to 2000 and 2008. Adhering the ambient PM2.5 level to the Malaysian Air Quality Standard IT-2 would reduce the national health endpoints mortality.
Biochar can be used for soil remediation in environmentally beneficial manner, especially when combined with nanomaterials. After a decade of research, still, no comprehensive review was conducted on the effectiveness of biochar-based nanocomposites in controlling heavy metal immobilization at soil interfaces. In this paper, the recent progress in immobilizing heavy metals using biochar-based nanocomposite materials were reviewed and compared their efficacy against that of biochar alone. In details, an overview of results on the immobilization of Pb, Cd, Cu, Zn, Cr, and As was presented by different nanocomposites made by various biochars derived from kenaf bar, green tea, residual bark, cornstalk, wheat straw, sawdust, palm fiber, and bagasse. Biochar nanocomposite was found to be most effective when combined with metallic nanoparticles (Fe3O4 and FeS) and carbonaceous nanomaterials (graphene oxide and chitosan). This study also devoted special consideration to different remediation mechanisms by which the nanomaterials affect the effectiveness of the immobilization process. The effects of nanocomposites on soil characteristics related to pollution migration, phytotoxicity, and soil microbial composition were assessed. A future perspective on nanocomposites' use in contaminated soils was presented.
Current worldwide projections of sea-level rise show a staggering increase in water level of up to 2 m by 2100 owing to global warming exacerbated by anthropogenically induced climate change. While amplified rates of sea-level rise is an immense hazard to coastal communities, storm surges are expected to increase in intensity and frequency making it an equally significant threat to coastal populations. In France, these hazards are not uncommon with records of extreme tempests every thousand years in the Holocene. Despite these recurring devastating events, in the Bay of Saint-Brieuc, Brittany, legislated laws for coastal management do not entirely focus on protecting littoral zones from such calamities. 130,739 people are concentrated in 21 municipalities with major cities located at close proximity to the shoreline with numerous socio-economic activities, which increases the vulnerability of the coastal population and infrastructures; thus, affirming the indispensable need of a thorough vulnerability assessment. Here, we conduct a mechanistic appraisal of the vulnerability of the bay considering thirteen parameters within three governing sub-systems that demonstrate the multidimensional dynamics in these municipalities. In the occasion of an extreme climatic event, our results of total vulnerability show risks in the sub-systems highlighting erosional processes due to augmented hydrodynamics, socio-economic and administrative vulnerabilities associated with anthropogenic development. Eight municipalities of the bay portray moderate to very high vulnerability and the remaining exhibits a lower risk; however, not devoid of high vulnerabilities for certain sub-systems. We posit that a more accurate fit for predicting the total vulnerability of the region can be achieved by exclusively integrating physical-natural and administrative sub-system vulnerabilities. We propose generic but requisite recommendations for Integrated Coastal Zone Management such as surveillance of urban development along the coast, implementation of coastal defense systems and appropriate industrial corridors to attenuate and dispose hazardous refuse.
Fluoroquinolone (FQ) antibiotics have become a subject of growing concern due to their increasing presence in the environment, particularly in the soil and groundwater. This review provides a comprehensive examination of the attributes, prevalence, ecotoxicity, and remediation approaches associated with FQs in environmental matrices. The paper discusses the physicochemical properties that influence the fate and transport of FQs in soil and groundwater, exploring the factors contributing to their prevalence in these environments. Furthermore, the ecotoxicological implications of FQ contamination in soil and aquatic ecosystems are reviewed, shedding light on the potential risks to environmental and human health. The latter part of the review is dedicated to an extensive analysis of remediation approaches, encompassing both in-situ and ex-situ methods employed to mitigate FQ contamination. The critical evaluation of these remediation strategies provides insights into their efficacy, limitations, and environmental implications. In this investigation, a correlation between FQ antibiotics and climate change is established, underlining its significance in addressing the Sustainable Development Goals (SDGs). The study further identifies and delineates multiple research gaps, proposing them as key areas for future investigational directions. Overall, this review aims to consolidate current knowledge on FQs in soil and groundwater, offering a valuable resource for researchers, policymakers, and practitioners engaged in environmental management and public health.