Chuck Chuan Ng

Molluscs, being highly susceptible to potentially toxic elements (PTEs) and easily accessible for human consumption, play a critical role in research on PTE pollution. This study focuses on Kukup Fishing Village in Johor, Malaysia, to investigate the levels of Cd, Cu, and Pb in seawater, sediment, and the soft tissues and shells of the gastropods Nerita articulata (lined nerite snail) and Cerithidea obtusa (obtuse horn shell). All collected samples were chemically digested before being analysed using the flame atomic absorption spectrometer (F-AAS). It is found that the PTEs are mostly accumulated in soft tissues and shells, followed by sediments and seawater, respectively. Besides, the results revealed that all study locations exhibited moderate to severe pollution, and the PTE concentrations in sea snails exceeded the thresholds set by the Malaysian Food Regulations (1985). The mean concentrations of the studied elements in the seawater, soft tissues, and shells of two studied species were found to be in the order of Pb > Cu > Cd. Additionally, Pb was heavily accumulated in the soft tissues of both species: N. articulata (712.587–723.242 ppm) and C. obtusa (705.935–708.626 ppm). Compared to N. articulata, C. obtusa showed a higher capacity to accumulate Cd (3.702–4.350 ppm) and Cu (92.687–157.445 ppm), particularly in the soft tissues. The shell of N. articulata and the soft tissue of C. obtusa were identified as potential biomonitoring indicators for Cd and Cu, respectively. It is recommended that the local Malaysian authorities could strengthen environmental management, implement regular monitoring, and raise public awareness to minimise seafood consumption from polluted areas as these measures could aid to reduce pollution, protect marine ecosystems, and safeguard public health.

Climate change, driven by greenhouse gas emissions, poses a significant threat to life and livelihoods globally. China, the world's largest carbon emitter, yet has a significant area of coastal blue carbon (CBC) ecosystems covering mangroves, salt marshes, and seagrass beds which are vital for carbon sequestration. This study assesses the current state of these ecosystems, evaluates Chinese policies for CBC conservation, appraise Chinese blue carbon (BC) market development and compares them with international efforts. The findings highlight inadequate conservation measures and a lack of specific laws and enforcement for BC protection in China. The BC market suffers from unclear responsibilities, dampening corporate participation. Recommendations include hastening legal frameworks, bolstering enforcement, defining BC rights and ownership, and involving the public in BC initiatives. A SWOT analysis underscores the need for urgent action to bolster China's CBC ecosystems and market development.

The global production of radioactive wastes is expected to increase in the coming years as more countries have resorted to adopting nuclear power to decrease their reliance on fossil-fuel-generated energy. Discoveries of remediation methods that can remove radionuclides from radioactive wastes, including those discharged to the environment, are therefore vital to reduce risks-upon-exposure radionuclides posed to humans and wildlife. Among various remediation approaches available, microbe-mediated radionuclide remediation have limited reviews regarding their advances. This review provides an overview of the sources and existing classification of radioactive wastes, followed by a brief introduction to existing radionuclide remediation (physical, chemical, and electrochemical) approaches. Microbe-mediated radionuclide remediation (bacterial, myco-, and phycoremediation) is then extensively discussed. Bacterial remediation involves biological processes like bioreduction, biosorption, and bioprecipitation. Bioreduction involves the reduction of water-soluble, mobile radionuclides to water-insoluble, immobile lower oxidation states by ferric iron-reducing, sulfate-reducing, and certain extremophilic bacteria, and in situ remediation has become possible by adding electron donors to contaminated waters to enrich indigenous iron- and sulfate-reducing bacteria populations. In biosorption, radionuclides are associated with functional groups on the microbial cell surface, followed by getting reduced to immobilized forms or precipitated intracellularly or extracellularly. Myco- and phycoremediation often involve processes like biosorption and bioaccumulation, where the former is influenced by pH and cell concentration. A Strengths, Weaknesses, Opportunities, and Threats (SWOT) analysis on microbial remediation is also performed. It is suggested that two research directions: genetic engineering of radiation-resistant microorganisms and co-application of microbe-mediated remediation with other remediation methods could potentially result in the discovery of in situ or ex situ microbe-involving radioactive waste remediation applications with high practicability. Finally, a comparison between the strengths and weaknesses of each approach is provided.

The accumulation of potentially toxic elements (PTEs) has raised public awareness due to harmful contamination to both human and marine creatures. This study was designed to determine the concentration of copper (Cu), zinc (Zn), cadmium (Cd), and nickel (Ni) in the intestine, kidney, muscle, gill, and liver tissues of local commercial edible fish, fourfinger threadfin (Eleutheronema tetradactylum), and black pomfret (Parastromateus niger) collected from Morib (M) and Kuala Selangor (KS). Among the studied PTEs, Cu and Zn were essential elements to regulate body metabolism with certain dosages required while Cd and Ni were considered as non-essential elements that posed chronic and carcinogenic risk. The concentration of PTEs in fish tissue samples was analyzed using flame atomic absorption spectrometry (F-AAS). By comparing the concentration of PTEs in fish tissues as a bioindicator, the environmental risk of Morib was more serious than Kuala Selangor because both fish species collected from Morib resulted in a higher PTEs concentration. For an average 62 kg adult with a fish ingestion rate (FIR) of 0.16 kg/person/day in Malaysia, the estimated weekly intake (EWI) of Cd from the consumption of E. tetradactylum (M: 0.0135 mg/kg; KS: 0.0134 mg/kg) and P. niger (M: 0.0140 mg/kg; KS: 0.0132 mg/kg) had exceeded the provisional tolerable weekly intake (Cd: 0.007 mg/kg) established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) and oral reference dose (ORD) values of Cd (0.001 mg/kg/day) as provided by the United States Environmental Protection Agency (USEPA) regional screening level, thus it posed chronic risks for daily basis consumption. Besides, the value of the carcinogenic risk of Cd (0.7−3 to 0.8−3) and Ni (0.5−3 to 0.6−3) were in between the acceptable range (10−6 to 10−4) of the health index that indicates a relatively low possibility cancer occurrence to the consumers in both Morib and Kuala Selangor. This study recommended FIR to be 0.80 kg/person/day to reduce the possibility of posing chronic and carcinogenic risks while at the same time obtaining the essential nutrients from the fish.

The environmental concern of plastic waste (PW) generation has escalated to an alarming level due to the versatility and high demand in various applications. In order to search for an effective way to utilise PW, reusing them for the production of construction material appears as an environmentally-friendly approach. This is also because conventional construction materials often consume high energy during production has caused many environmental impacts. This review paper summarises the previous studies on reusing various PW as raw material and aggregate for construction and its properties with special attention to bricks and paving blocks. This paper begins by illustrating on the properties of plastics and the impacts of PW to the environment. Followed by discussion on reusing PW and its impacts on the overall properties of construction material. This review found that limited studies had been conducted on the usage of PW in the production of the paving block. Besides, most of the studies focused predominantly on compressive strength and water absorption as the main parameters to evaluate the characteristics of bricks and paving blocks. It is concluded that the use of PW in construction material could possibly serve as a sustainable source for construction material in the future.

Plastic waste is a significant environmental problem for almost all countries; therefore, protecting the environment from the problem is crucial. The most sensible solution to these problems is substituting the natural aggregates with substantial plastic waste in various building materials. This study aimed to optimise the mixed design ratio of cement brick containing plastic waste as aggregate replacement. Plastic cement brick mixtures were prepared by the incorporation of four different types of plastic waste such as polyethylene terephthalate (PET), high-density polyethylene, low-density polyethylene and polypropylene into cement bricks with different cement contents (150, 300 and 450 g) and plastic replacement percentages (0, 3 and 6%). Compressive strength and water absorption of the plastic cement bricks were analysed using a statistical model through the response surface methodology. It revealed the optimum cement brick mixed design is C3-1% PET with the compressive strength of 27.50 MPa and water absorption of 1.16%. The optimised plastic cement brick also satisfied the general ASTM C62-17 requirements for building bricks despite the higher porosity observed by the scanning electron microscopy. The results from Fourier transform infrared spectroscopy analysis also showed that the addition of the plastic waste into cement brick was unlikely to modify the chemical compound within the cement brick mixtures. Thus, the proposed mathematical model can predict the required hardened properties of plastic cement bricks and could lead to greater utilisation of plastic waste in building materials.

Plastic waste accumulation in the environment due to huge volumes of plastic waste produced daily with no effective disposal method and waste management have raised public awareness to look for an alternative to replace the current disposal techniques. Waste utilisation or plastic recycling has been regarded as an excellent method to reduce the abundant amount of plastic waste as well as minimising the environmental impacts. In this article, a total of 163 previous studies between 2012 and 2021 had been reviewed to discuss the utilisation of different types of plastic waste as aggregate in construction materials. This paper evaluates on the use of plastic as aggregate in terms of the physical, mechanical and durability properties of the construction materials as well as the environmental and cost analyses. It was found that the mechanical and durability properties of produced materials were altered after the addition of plastic as aggregates; however, the materials are still fulfilling the requirement of construction materials. Besides, a general SWOT analysis to highlight the advantages and disadvantages of plastic waste utilisation was also conducted.

CLIMATE EDUCATION FOR WOMEN AND YOUTH Around the world, people still lack basic awareness and understanding of the drivers and impact of climate change, as well as options for reducing carbon emissions and adapting to the climate change impacts. In addition, climate change impacts are not equally distributed. Gender inequalities and development gaps increase the impacts of climate change for women and young people. Driving climate action through educating and empowering women and youth could lead to building resilience within communities. Thus, education and training are crucial to building capacity and enhance their ability to tackle climate change, especially as most of them have no access to information and resources related to climate action. Despite the evidence that education has a strong role to play in both climate adaptation and mitigation, the global education community has done little to advance wide-scale education efforts. Solid, coherent policies and plans are the bedrock on which to build sustainable education systems, achieve educational development goals and contribute effectively to lifelong learning. At a time of growing inequality, closing the gaps in access to quality education requires a long-term vision, engagement, and effective collaboration between various stakeholders. To do that, it’s critical to develop climate educational guides for developing countries that include the most important elements about formal and informal education for women and young people, as well as relevant learning materials and tools. Establishing a climate education coalition provides a forum for expert discussion and unlocks the potential of collaborative work. Embedding climate topics into formal and non-formal education is another priority area for action that could contribute to increasing climate awareness among youth. Community-level climate education projects and initiatives could be a powerful tool for educating and empowering women. Thus, governments and local authorities should ensure funds and provide resources for these projects and initiatives.

E-waste is one of the most pressing challenges of our time, yet it is often ignored, especially in Southeast Asia. The “tsunami of e-waste” in the region has been putting our lives and our environment at risk. With the extensive use of electrical and electronic devices, we are also contributing to harming the environment and quickening the climate change by producing and discarding e-waste. Youths are among major users of electronic devices, and hunger for upgraded and newer versions. However, there is still a lack of sensitization on e-waste management issues in the Southeast Asia region. Why should not the young people be pioneers in educating this challenge to the young public? Our FRE-E-WASTE project team is firm in our belief that youths should take the lead in bringing to light this aspect of climate justice, to the best of our ability. Implemented by a group of ASEAN environmental enthusiasts, STEP Forward Education and supported by the U.S. Department of State and the Young Southeast Asian Leaders Initiative (YSEALI), FRE-E-WASTE Project seeks to bring together a group of Southeast Asian environmental enthusiasts aged between 18 and 35 to connect and collaborate on e-waste issues in the region and eventually to create a toolkit about e-waste for the Southeast Asia region.

E-waste, also known as waste from electrical and electronic equipment, is a solid waste that accumulates quickly due to high demand driven by the market for replacing newer electrical and electronic products. The global e-waste generation is estimated to be between 53.6 million tons, and it is increasing by 3–5% per year. Metals make-up approximately 30% of e-waste, which contains precious elements Au, Ag, Cu, Pt, and other high-value elements, valued at USD 57 billion, which is driving the e-waste recycling industry. It is noteworthy that the recycling of precious elements from e-waste has emerged as a profitable enterprise in several parts of developing nations. E-waste contains 50–100 times higher levels of precious metals compared to natural ores, making it suitable for mining. E-waste recycling in developing nations, mostly occurs through the informal sector comprising manual collection, crushing, segregation and selling of precious elements, such as Au, Ag, Cu, Pb, Pt, and other rare elements (Nd, In, and Ga). The organized sector, on the other hand, mostly employs mechano-chemical methods, such as pyrometallurgy, hydrometallurgy, and bio-hydrometallurgy, which have serious environmental consequences. Both the informal and formal sectors of e-waste processing lead to the leaching of toxic elements into groundwater and soils. Owing to the lesser efficiency of greener technologies, such as phytoremediation and bioremediation, their use in precious metal extraction is very limited. However, this review explores several hyper-accumulating and tolerant plants viz. Brassica juncea and Berkheya coddii, which holds great potential in phytomining of precious metal from e-waste. Thus, the state of the art in precious metal extraction from e-waste as well as the advantages and disadvantages of different metal extraction technologies has been reviewed.

Phytoremediation is a biological remediation technique known for low-cost technology and environmentally friendly approach, which employs plants to extract, stabilise, and transform various compounds, such as potentially toxic elements (PTEs), in the soil or water. Recent developments in utilising chelating agents soil remediation have led to a renewed interest in chelate-induced phytoremediation. This review article summarises the roles of various chelating agents and the mechanisms of chelate-induced phytoremediation. This paper also discusses the recent findings on the impacts of chelating agents on PTEs uptake and plant growth and development in phytoremediation. It was found that the chelating agents have increased the rate of metal absorption and translocation up to 45% from roots to the aboveground plant parts during PTEs phytoremediation. Besides, it was also explored that the plants may experience some phytotoxicity after adding chelating agents to the soil. However, due to the leaching potential of synthetic chelating agents, the use of organic chelants have been explored to be used in PTEs phytoremediation. Finally, this paper also presents comprehensive insights on the significance of using chelating agents through SWOT analysis to discuss the advantages and limitations of chelate-induced phytoremediation.

Most phyto-remediation studies have been conducted merely on a single type of contaminant element without consideration of the influence of other co-existent contaminants. In this study, Vetiveria zizanioides (Linn.) Nash was evaluated in both single and mixed heavy metal (Cd, Pb, Cu and Zn) spiked contaminated soil. The plant growth, metal accumulation and overall efficiency of metal uptake by different plant parts (lower root, upper root, lower tiller and upper tiller) were investigated in detail. The relative growth performance, metal tolerance and phyto-assessment of heavy metal in roots and tillers of Vetiver grass were assessed. Metals in plants were measured using the flame atomic absorption spectrometry (F-AAS) after acid digestion. The root-tiller (R/T) ratio, tolerance index (TI), translocation factor (TF), biological concentration factor (BCF), biological accumulation coefficient (BAC) and metal uptake efficacy were estimated to examine the ability of metal accumulation and translocation in Vetiver grass. No significant difference (p > 0.05) of plant height was observed among all single and mixed heavy metal spiked soils compared with the control. However, significantly higher (p < 0.05) heavy metal (Cd, Pb, Cu and Zn) accumulations were found in roots, tillers and overall total accumulation of the individual spiked metal as compared with other treatments. Vetiver grass grown in the mixed Cd + Pb + Cu + Zn spiked soils accumulated the highest Zn (3322 ± 21.6 mg/kg) followed by Cu (430 ± 11.4 mg/kg), Pb (197 ± 13.5 mg/kg) and Cd (100 ± 0.7 mg/kg). Vetiver grass grown in mixed Cd + Pb, Cu + Zn and Cd + Pb + Cu + Zn spiked soils accumulated higher heavy metal concentrations than from the single spiked soil with the following order of metals: Zn > > Cu > Pb > Cd. Moreover, lower roots and lower tillers of Vetiver grass revealed a strong tendency for greater uptake and accumulation of all four heavy metals in both single and/or mixed spiked contaminated soils.

Over the years, ethylene-diamine-tetra-acetate (EDTA) has been widely used for many purposes. However, there are inadequate phytoassessment studies conducted using EDTA in Vetiver grass. Hence, this study evaluates the phytoassessment (growth performance, accumulation trends, and proficiency of metal uptake) of Vetiver grass, Vetiveria zizanioides (Linn.) Nash in both single and mixed heavy metal (Cd, Pb, Cu, and Zn)—disodium EDTA-enhanced contaminated soil. The plant growth, metal accumulation, and overall efficiency of metal uptake by different plant parts (lower root, upper root, lower tiller, and upper tiller) were thoroughly examined. The relative growth performance, metal tolerance, and phytoassessment of heavy metal in roots and tillers of Vetiver grass were examined. Metals in plants were measured using the flame atomic absorption spectrometry (F-AAS) after acid digestion. The root-tiller (R/T) ratio, biological concentration factor (BCF), biological accumulation coefficient (BAC), tolerance index (TI), translocation factor (TF), and metal uptake efficacy were used to estimate the potential of metal accumulation and translocation in Vetiver grass. All accumulation of heavy metals were significantly higher (p < 0.05) in both lower and upper roots and tillers of Vetiver grass for Cd + Pb + Cu + Zn + EDTA treatments as compared with the control. The single Zn + EDTA treatment accumulated the highest overall total amount of Zn (8068 ± 407 mg/kg) while the highest accumulation for Cu (1977 ± 293 mg/kg) and Pb (1096 ± 75 mg/kg) were recorded in the mixed Cd + Pb + Cu + Zn + EDTA treatment, respectively. Generally, the overall heavy metal accumulation trends of Vetiver grass were in the order of Zn >>> Cu > Pb >> Cd for all treatments. Furthermore, both upper roots and tillers of Vetiver grass recorded high tendency of accumulation for appreciably greater amounts of all heavy metals, regardless of single and/or mixed metal treatments. Thus, Vetiver grass can be recommended as a potential phytoextractor for all types of heavy metals, whereby its tillers will act as the sink for heavy metal accumulation in the presence of EDTA for all treatments.

Sources of soil contamination can exist in various types of conditions including in the form of semifluids. In this study, 3 different types of tropical plants, Acacia (Acacia mangium Willd), Mucuna (Mucuna bracteata DC. ex Kurz) and Vetiver (Vetiveria zizanioides L. Nash), were tested under different levels of soil-leachate conditions. The relative growth rate, metal tolerance, and phytoassessment of cadmium (Cd) and lead (Pb) accumulation in the roots and shoots were determined using flame atomic absorption spectrometry. Tolerance index, translocation factor, metal accumulation ratio, and percentage metal efficacy were applied to assess the metal translocation ability among all the 3 types of plants. Significantly higher (P < .05) accumulation of Cd and Pb was exhibited in the roots and shoots of all 3 plants growing under the soil-leachate conditions. However, negative growth performance and plant withering were observed in both Acacia and Mucuna with increased application of higher soil-leachate levels. Vetiver accumulated remarkably higher total concentration of Cd (116.16-141.51 mg/kg) and Pb (156.37-365.27 mg/kg) compared with both Acacia and Mucuna. The overall accumulation trend of Cd and Pb in the 3 plants growing under the soil-leachate conditions was in the order of Vetiver > Acacia > Mucuna. The findings of the study suggest that Vetiver has great potential as Cd and Pb phytoremediator in soil-leachate conditions.

Various types of plant species have been extensively used for heavy metals phyto-remediation without taking into consideration its tolerance threshold. In this study, Vetiver grass, Vetiveria zizanioides (Linn.) Nash was evaluated under five different sets of contaminated spiked cadmium (5Cd, 10Cd, 50Cd, 100Cd and 150Cd mg/kg) and lead (50Pb, 100Pb, 200Pb, 400Pb and 800Pb mg/kg) concentration levels in soil. The growth performance, metal tolerance and phyto-assessment of Cd and Pb in the roots and tillers were assessed using flame atomic absorption spectrometry (FAAS). Tolerance index (TI), translocation factor (TF), biological transfer factor (BTF), biological accumulation coefficient (BAC) and metal uptake efficacy were used to determine the Cd and Pb translocation capability in Vetiver grass. Significantly higher (p<0.05) accumulation of Cd and Pb was recorded in the roots of all spiked treatments. Furthermore, strong and significantly positive correlations were exhibited between the increased levels of spiked heavy metal concentrations with both Cd (r=0.975) and Pb (r=0.952) accumulations. The results of this study showed Vetiver grass as an effective phyto-stabilizer for both Cd and Pb. Nevertheless, the growth of Vetiver grass was restricted when the tolerance threshold of 100 mg/kg (dry weight basis) Cd was exceeded in the contaminated soil.

This paper investigates the local implementation of Malaysian public GAP standard called MyGAP by examining its effectiveness in raising the awareness and improving the pesticide use practices of participant smallscale farmers toward better food safety and quality assurance. For this objective, 19 MyGAP certified and 57 uncertified durian farms in the state of Pahang, Malaysia were surveyed. The research found that certified farm managers have a much better understanding of the basic intent of the policy than uncertified farms, reflecting the individually oriented interests and motivations of participant farmers in the national scheme. Their interests in and assessment of the merits of the scheme are found to concentrate in economic realms rather than in the original policy goal of food safety and quality assurance. As regards pesticide use practices, certified farms showed a much better performance than uncertified farms in record keeping and pesticide use and management. There remains a question, however, whether it is due to the farming practices improved through MyGAP adoption or due to the participation of farms already well-performing prior to MyGAP adoption.

Tropical grasses are fast growing and often used for phytoremediation. Three different types of tropical grasses: Vetiver (V. zizanoides), Imperata (I. cylindrical) and Pennisetum (P. purpureum) tested in different growth media of spiked heavy metal contents under the glasshouse environment of RimbaIlmu for 60-day. The growth performance, metals tolerance and phyto-assessment of cadmium (Cd), lead (Pb), zinc (Zn) and copper (Cu) in shoots and roots were assessed using flame atomic absorption spectrometry (FAAS).Tolerance index (TI), translocation factor (TF), biological accumulation coefficient (BAC), biological concentration factor (BCF), and uptake efficacy was applied to evaluate the metal translocation ability among all three grasses. All three grasses showed significantly higher (p<0.05) accumulation of the total heavy metals in the spiked metal treatment compared with other tested treatments. Vetiver accumulated remarkably higher total concentration of Cd (93.08 ± 3.81 mg/kg) and Zn (1284.00 ± 234.83 mg/kg) than both Imperata and Pennisetum. The overall trend of heavy metals accumulation for all three grasses followed the order of Zn>Pb>Cd>Cu. The results of study suggested that both Imperata and Pennisetum are commendable and potential phytoextractors for Zn as well as phytostabilizers for Cd, Pb and Cu, respectively.

The growth response, metal tolerance and phytoaccumulation properties of water spinach (Ipomoea aquatica) and okra (Abelmoschus esculentus) were assessed under different contaminated spiked metals: control, 50 mg Pb/kg soil, 50 mg Zn/kg soil and 50 mg Cu/kg soil. The availability of Pb, Zn and Cu metals in both soil and plants were detected using flame atomic absorption spectrometry. The concentration and accumulation of heavy metals from soil to roots and shoots (edible parts) were evaluated in terms of translocation factor, accumulation factor and tolerance index. Okra recorded the highest accumulation of Pb (80.20 mg/kg) in its root followed by Zn in roots (35.70 mg/kg) and shoots (34.80 mg/kg) of water spinach, respectively. Different accumulation trends were observed with, Pb > Zn > Cu in okra and Zn > Pb > Cu in water spinach. Significant differences (p < 0.01) of Pb, Zn and Cu accumulation were found in both water spinach and okra cultivated among tested treatments. However, only the accumulation of Pb metal in the shoots of water spinach and okra exceeded the maximum permissible levels of the national Malaysian Food Act 1983 and Food Regulations 1985 ([2006]) as well as the international Codex Alimentarius Commission limits. This study has shown that both water spinach and okra have good potential as Pb and Zn phytoremediators.

Three different types of low cost soil amendments, namely, EDTA, elemental S and N-fertilizer, were investigated with Vetiver grass, Vetiveria zizanioides (Linn.) Nash growing under highly mixed Cd–Pb contamination conditions. A significant increase (p < 0.05) in Cd and Pb accumulation were recorded in the shoots of all EDTA and N-fertilizer assisted treatments. The accumulation of Cd in 25 mmol EDTA/kg soil and 300 mmol N/kg soil showed relatively higher translocation factor (1.72 and 2.15) and percentage metal efficacy (63.25 % and 68.22 %), respectively, compared to other treatments. However, it was observed that the increased application of elemental S may inhibit the availability of Pb translocation from soil-to-root and root-to-shoot. The study suggests that viable application of 25 mmol EDTA/kg, 300 mmol N/kg and 20 mmol S/kg soil have the potential to be used for soil amendment with Vetiver grass growing under contaminated mixed Cd–Pb soil conditions.