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Study on Carapace Width Growth Band Counts Relationship of Orange Mud Crab, Scylla olivacea (Herbst, 1796) from Terengganu Coastal Waters, Malaysia

Hasyima Ismail N, Amin Safwan A, Fairuz Fozi N, Megat FH, Muhd Farouk H, Kamaruddin SA, et al.

Pak J Biol Sci, 2017;20(3):140-146.
PMID: 29023005 DOI: 10.3923/pjbs.2017.140.146

BACKGROUND: Orange mud crab Scylla olivacea is one of the most important fisheries resources. A new development in ageing technique of crustaceans has been introduced. The detection of growth band deposited in hard structure of gastric mill in the cardiac stomach are found retained after moulting process can be used as age indicator and growth estimation.
OBJECTIVE: This study was carried out to determine the comparison between carapace width and growth band count of S. olivacea in Malaysia.
MATERIALS AND METHODS: Samples were collected from Setiu Wetlands, Terengganu, Malaysia from February until August, 2016. Samples were categorized based on their morphological measurements. The mesocardiac and zygocardiac ossicles in the gastric mill of S. olivacea was dissected out and preserved in solutions and underwent a cross sectioning process. A total of 76 of wild S. olivacea ranging from 6.56 to 12.84 cm in carapace width were analysed. The growth band counts were examined for each individual and ranging from 1 to 3 band counts.
RESULTS: A positive linear relation was observed between CW and GBC with r2 = 0.5178, p<0.01. Overall, there was a strong, positive correlation between CW and GBC. Increase in CW were correlated with increases in GBC respectively for this species.
CONCLUSION: Therefore, the carapace width, growth band counts and body weight can be used to improve data on growth, recruitment, maturation and mortality. Thus, this study would able to improve new ageing technique and contribute greatly to improve the conservation and management of S. olivacea in Setiu Wetlands, Terengganu, Malaysia.

Matched MeSH terms: Environmental Monitoring/methods*
A review of personal exposure studies in selected Asian countries' public transport microenvironments: lessons learned and future directions

Otuyo MK, Nadzir MSM, Latif MT, Din SAM

Environ Sci Pollut Res Int, 2023 Dec;30(58):121306-121337.
PMID: 37993649 DOI: 10.1007/s11356-023-30923-9

This comprehensive paper conducts an in-depth review of personal exposure and air pollutant levels within the microenvironments of Asian city transportation. Our methodology involved a systematic analysis of an extensive body of literature from diverse sources, encompassing a substantial quantity of studies conducted across multiple Asian cities. The investigation scrutinizes exposure to various pollutants, including particulate matters (PM10, PM2.5, and PM1), carbon dioxide (CO2), formaldehyde (CH2O), and total volatile organic compounds (TVOC), during transportation modes such as car travel, bus commuting, walking, and train rides. Notably, our review reveals a predominant focus on PM2.5, followed by PM10, PM1, CO2, and TVOC, with limited attention given to CH2O exposure. Across the spectrum of Asian cities and transportation modes, exposure concentrations exhibited considerable variability, a phenomenon attributed to a multitude of factors. Primary sources of exposure encompass motor vehicle emissions, traffic dynamics, road dust, and open bus doors. Furthermore, our findings illuminate the influence of external environments, particularly in proximity to train stations, on pollutant levels inside trains. Crucial factors affecting exposure encompass ventilation conditions, travel-specific variables, seat locations, vehicle types, and meteorological influences. The culmination of this rigorous review underscores the need for standardized measurements, enhanced ventilation systems, air filtration mechanisms, the adoption of clean energy sources, and comprehensive public education initiatives aimed at reducing pollutant exposure within city transportation microenvironments. Importantly, our study contributes to the growing body of knowledge surrounding this subject, offering valuable insights for policymakers and researchers dedicated to advancing air quality standards and safeguarding public health.

Matched MeSH terms: Environmental Monitoring/methods
Fulltext Development of Biopolymer and Conducting Polymer-Based Optical Sensors for Heavy Metal Ion Detection

Ramdzan NSM, Fen YW, Anas NAA, Omar NAS, Saleviter S

Molecules, 2020 May 30;25(11).
PMID: 32486124 DOI: 10.3390/molecules25112548

Great efforts have been devoted to the invention of environmental sensors as the amount of water pollution has increased in recent decades. Chitosan, cellulose and nanocrystalline cellulose are examples of biopolymers that have been intensively studied due to their potential applications, particularly as sensors. Furthermore, the rapid use of conducting polymer materials as a sensing layer in environmental monitoring has also been developed. Thus, the incorporation of biopolymer and conducting polymer materials with various methods has shown promising potential with sensitively and selectively toward heavy metal ions. In this feature paper, selected recent and updated investigations are reviewed on biopolymer and conducting polymer-based materials in sensors aimed at the detection of heavy metal ions by optical methods. This review intends to provide sufficient evidence of the potential of polymer-based materials as sensing layers, and future outlooks are considered in developing surface plasmon resonance as an excellent and valid sensor for heavy metal ion detection.

Matched MeSH terms: Environmental Monitoring/methods
Environmental DNA metabarcoding of freshwater fish in Malaysian tropical rivers using short-read nanopore sequencing as a potential biomonitoring tool

Munian K, Ramli FF, Othman N, Mahyudin NAA, Sariyati NH, Abdullah-Fauzi NAF, et al.

Mol Ecol Resour, 2024 May;24(4):e13936.
PMID: 38419264 DOI: 10.1111/1755-0998.13936

The approach of combining cost-effective nanopore sequencing and emerging environmental DNA (eDNA) metabarcoding could prove to be a promising tool for biodiversity documentation, especially in Malaysia. Given the substantial funding constraints in recent years, especially in relation to the country's biodiversity, many researchers have been limited to conduct restricted research without extended monitoring periods, potentially hindering comprehensive surveys and could compromise the conservation efforts. Therefore, the present study aimed to evaluate the application of eDNA metabarcoding on freshwater fish using short reads generated through nanopore sequencing. This assessment focused on species detection in three selected rivers within the Endau Rompin Landscape in Malaysia. Additionally, the study compared levels of species detection between eDNA metabarcoding and conventional sampling methods, examined the effectiveness of primer choice, and applied both metabarcoding and shotgun sequencing to the eDNA approach. We successfully identified a total of 22 and 71 species with an identification threshold of >97% and >90%, respectively, through the MinION platform. The eDNA metabarcoding approach detected over 13% more freshwater fish species than when the conventional method was used. Notably, the distinction in freshwater fish detection between eDNA primers for 12S rRNA and cytochrome oxidase I was insignificant. The cost for eDNA metabarcoding proved to be more effective compared to conventional sampling with cost reduction at 33.4%. With favourable cost-effectiveness and increased species detection, eDNA metabarcoding could complement existing methods, enhance holistic diversity documentation for targeted habitats and facilitate effective conservation planning.

Matched MeSH terms: Environmental Monitoring/methods
An assessment of the potential health hazards associated with metal contamination in a variety of consumable species living along the industrialized coastline of East Java, Indonesia

Marchellina A, Soegianto A, Putranto TWC, Mukholladun W, Payus CM, Irnidayanti Y

Mar Pollut Bull, 2024 May;202:116375.
PMID: 38621352 DOI: 10.1016/j.marpolbul.2024.116375

The massive industrial growth in Gresik, East Java, Indonesia has the potential to result in metal contamination in the nearby coastal waters. The purpose of this study was to analyze the metal concentrations in edible species from the Gresik coastal waters and evaluate the potential health risks linked to this metal contamination. Metal concentrations (Cu, Fe, Pb, Zn, As, Cd, Ni, Hg, and Cr) in fish and shrimp samples mostly met the maximum limits established by national and international regulatory organizations. The concentrations of As in Scatophagus argus exceed both the permissible limit established by Indonesia and the provisional tolerable weekly intake (PTWI). The As concentration in Arius bilineatus is equal to the PTWI. The target cancer risk (TCR) values for both As and Cr in all analyzed species exceed the threshold of 0.0001, suggesting that these two metals possess the potential to provide a cancer risk to humans.

Matched MeSH terms: Environmental Monitoring*
Organophosphate esters in water and air: A minireview of their sources, occurrence, and air-water exchange

Marlina N, Hassan F, Chao HR, Latif MT, Yeh CF, Horie Y, et al.

Chemosphere, 2024 May;356:141874.
PMID: 38575079 DOI: 10.1016/j.chemosphere.2024.141874

Organophosphate esters (OPEs) have received considerable attention in environmental research due to their extensive production, wide-ranging applications, prevalent presence, potential for bioaccumulation, and associated ecological and health concerns. Low efficiency of OPE removal results in the effluents of wastewater treatment plants emerging as a significant contributor to OPE contamination. Their notable solubility and mobility give OPEs the potential to be transported to coastal ecosystems via river discharge and atmospheric deposition. Previous research has indicated that OPEs have been widely detected in the atmosphere and water bodies. Atmospheric deposition across air-water exchange is the main input route for OPEs into the environment and ecosystems. The main processes that contribute to air-water exchange is air-water diffusion, dry deposition, wet deposition, and the air-water volatilization process. The present minireview links together the source, occurrence, and exchange of OPEs in water and air, integrates the occurrence and profile data, and summarizes their air-water exchange in the environment.

Matched MeSH terms: Environmental Monitoring*
A novel quantity assessment of landscape ecological risk using human-nature driving mechanism for sustainable society

Liu L, Wei J, Luo P, Zhang Y, Wang Y, Elbeltagi A, et al.

Sci Total Environ, 2024 Oct 15;947:173892.
PMID: 38876337 DOI: 10.1016/j.scitotenv.2024.173892

The rapid advancement of global economic integration and urbanization has severely damaged the stability of the ecological environment and hindered the ecological carbon sink capacity. In this study, we evaluated the spatiotemporal evolution pattern of landscape ecological risk (LER) in the Loess Plateau from 2010 to 2020. This was examined under the driving mechanism of human and natural dual factors. We combined the random forest algorithm with the Markov chain to jointly simulate and predict the development trend of LER in 2030. From 2010 to 2020, LER on the Loess Plateau showed a distribution pattern with higher values in the southeast and lower values in the northwest. Under the interaction of human and natural factors, annual precipitation exerted the strongest constraint on LER. The driving of land use and natural factors significantly influenced the spatial differentiation of the LER, with a q-value >0.30. In all three projected scenarios for 2030, there was an increase in construction land area and a significant reduction in cultivated land area. The urban development scenario showed the greatest expansion of high-risk areas, with a 5.29 % increase. Conversely, the ecological protection scenario showed a 1.53 % increase in high-risk areas. The findings have provided a reference for ecological risk prevention and control, and sustainable development of the ecological environment in arid regions.

Matched MeSH terms: Environmental Monitoring/methods
Toxicity factors, ecological and health risk assessments of heavy metal in the urban soil: a case study of an agro-machinery area in a developing country

Islam MS, Al Bakky A, Saikat MSM, Antu UB, Akter R, Roy TK, et al.

Environ Geochem Health, 2024 Sep 24;46(11):437.
PMID: 39316128 DOI: 10.1007/s10653-024-02213-x

The contribution of heavy metals in surface soils by the influences of agro-machinery factories is a significant growing concern. Heavy metals were analyzed by inductively coupled plasma mass spectrometry technique to assess human and ecological risks. The concentrations of Fe, Cd, Cr, Cu, As, Pb, Mn, Ni, and Zn in soil ranged from 18,274-22,652, 2.06-4.92, 24.8-41.9, 126.8-137.5, 9.20-25.2, 17.8-46.1, 114.4-183.1, 86.9-118.1, and 101.6-159.6 mg/kg, respectively. The enrichment factor values of heavy metals were greater than 1.5, suggesting severe anthropogenic activities such as untreated waste discharging, burning of metallic wastes, wear, and tear, and dismantling of old batteries for heavy metals enrichment in studied soil. The contamination factor indicates considerable to very high contamination of heavy metals in soil. Moderate to high ecological risk was observed for analyzed metals which mainly originated from the maintenance and repairing of various engines in the workshop and welding and soldering of metallic substances. The target hazard quotient (THQ) was ranged from 6.99E-04 to 2.21E-01 for adults and 5.59E-03 to 1.82E + 00 for children, respectively; indicating children were more sensitive to heavy metals exposure from soil dust. The carcinogenic risk of As (1.72E-05) exceeded the USEPA acceptable limits indicating cancer risk to the residence. The current emphasized the significance of intensive heavy metals monitoring in surface soils around the agro-machinery areas due to their potential health risks associated with children.

Matched MeSH terms: Environmental Monitoring/methods
Assessing and anticipating environmental challenges in Lahore, Pakistan: future implications of air pollution on sustainable development and environmental governance

Nasar-U-Minallah M, Jabbar M, Zia S, Perveen N

Environ Monit Assess, 2024 Aug 30;196(9):865.
PMID: 39212804 DOI: 10.1007/s10661-024-12925-3

Urban environment and air quality are changing primarily due to land use land cover (LULC) changes, economic activity, and urbanization. Air pollution has been increasingly acknowledged as a major issue for cities due to its extensive effects on health and well-being. As the second most populous city in the country, Lahore faces alarming levels of air pollutants, which induced this study to focus on the pervasive issue of air pollution in Lahore. For this, the study collected air pollutants data from the Environmental Protection Department of Punjab and analyzed them using the ARIMA model. In the research results, both the observed data and predictive models uncovered concerning trends in pollutant concentrations, ultimately portraying a concerning picture for air quality management. Carbon monoxide (CO) levels show a consistent rise, surpassing Pakistan's environmental standards by 2025. Similarly, nitrogen dioxide (NO2) concentrations escalate, exceeding prescribed standards. Ground-level ozone (O3) also demonstrates a substantial increase, surpassing standards by 2025. Both PM2.5 and PM10 exhibit marked upward trends, projected to exceed recommended limits, particularly PM10 throughout the study year. The Air Quality Index exhibits an observable upward trend, fluctuating between 70 and 442 from 2015 to 2020. Similarly, a positive correlation was found between population growth and land use conversion into residential areas. Projections suggest a continuous increase, potentially hitting a severe level of 500 during winter by 2025. These findings point to an impending air pollution crisis, demanding urgent action to address the hazardous situation in the city. The study recommends that urban air pollution should be reduced, and the negative health effects of air pollution should be minimized using vegetation barriers, screens, and greening initiatives. Strict regulations and monitoring initiatives need to be put in place in big cities to monitor pollution and vegetation.

Matched MeSH terms: Environmental Monitoring*
Fulltext A comprehensive Review into Emission Sources, Formation Mechanisms, Ecological Effects, and Biotransformation Routes of Halogenated Polycyclic Aromatic Hydrocarbons (HPAHs)

Ali L, Alam A, Ali AM, Teoh WY, Altarawneh M

Ecotoxicol Environ Saf, 2024 Nov 01;286:117196.
PMID: 39426109 DOI: 10.1016/j.ecoenv.2024.117196

Halogenated polycyclic aromatic hydrocarbons (HPAHs, H = F, Cl, Br) are a new class of PAHs derivatives that mainly originate from the incomplete combustion of halogen-laden materials and via metallurgical operations. These compounds circulate extensively in various environmental matrices. This survey provides a comprehensive review on governing synthesis routes of HPAHs, their environmental occurrence, and their health and ecological effects. The review comprehensively enlists and presents emission sources of these emerging organic pollutants into the air that serves as their main reservoir. The formation of HPAHs ensues through successive addition reactions of related precursors accompanied by ring cyclization steps; in addition to direct unimolecular fragmentation of parents halogenated. Halogenation of parent PAHs rapidly occurs in saline ecosystems, thus multiplying the availability of these notorious compounds in the environment. Certain HPAHs appear to be more carcinogenic than dioxins. Transmission routes of HPAHs from their emission sources to water bodies, soil, aquatic life, plants, terrestrial animals, and humans are well-documented. Later, the direct and indirect diffusion of HPAHs from air to the biotic (plants, animals, humans) and abiotic components (soil, water, sediments) are described in detail. The study concludes that HPAHs are permeable to the carbon matrices resulting in the alleviation of the source-to-sink interface. As a potential future perspective, understanding the transmission interfaces lays a foundation to intervene in the introduction of these toxicants into the food chain.

Matched MeSH terms: Environmental Monitoring*
Toxicity assessment of heavy metals translocation in maize grown in the Ganges delta floodplain soils around the Payra power plant in Bangladesh

Islam MS, Al Bakky A, Ahmed S, Islam MT, Antu UB, Saikat MSM, et al.

Food Chem Toxicol, 2024 Nov;193:115005.
PMID: 39284411 DOI: 10.1016/j.fct.2024.115005

As a cereal crop, maize ranked third place after wheat and rice in terms of land area coverage for its cultivation, and in Bangladesh, it ranked second place after rice in its production. As the substitution of wheat products, maize has been used widely in baking for human consumption and animal fodder. However, maize grown in this soil around the coal-burning power plant may cause heavy metals uptake that poses a risk to humans. The study was conducted at the maize fields in the Ganges delta floodplain soils of Bangladesh to know the concentration of eight heavy metals (Ni, Cr, Cd, Mn, As, Cu, Zn, and Pb) in soil and maize samples using an inductively coupled plasma mass spectrometer (ICP-MS) and to estimate the risk of heavy metals in maize grains. Mean concentrations of heavy metals (mg/kg) in soil were in decreasing order of Zn (10.12) > Cu (10.02) > Mn (5.48) > Ni (4.95) > Cr (3.72) > As (0.51) > Pb (0.27) > Cd (0.23). The plant tissues showed the descending order of heavy metal concentration as roots > grains > stems > leaves. BCF values for As, Cd, Pb, and Mn in roots were higher than 1.0, indicating considerable accumulation of these elements in maize via roots. Total hazard quotient (ƩTHQ) of heavy metals through maize grain consumption was 3.7E+00 and 3.9E+00 for adults and children, respectively, indicating non-cancer risk to the consumers. Anthropogenic influences contributed to the heavy metals enrichment in the Ganges delta floodplain soils around the thermal plant, and potential risks (non-carcinogenic and carcinogenic) were observed due to the consumption of maize grain cultivated in the study area.

Matched MeSH terms: Environmental Monitoring/methods
Key insight of groundwater quality and nutrients contamination in Pulau Kapas, Terengganu

Cheong SM, Joseph B, Ahmad Idham K, Ahmad Rusyaidi MM, Yong JC, Adiana G

Mar Pollut Bull, 2024 Dec;209(Pt A):117102.
PMID: 39406063 DOI: 10.1016/j.marpolbul.2024.117102

Pulau Kapas is tropical island which dominantly depends on land-supplied and groundwater for freshwater sources. The groundwater quality was monitored monthly, to identify the possible factors effecting the groundwater quality throughout May to October 2022. Physico-chemical parameters were in-situ measured and groundwater were collected for nutrients analysis in the laboratory. The concentration of ammonium, phosphate, nitrite, and nitrate were in the range of 0.07-1.08 mg/L, 0.00-0.06 mg/L, BDL-18 × 10-4 mg/L and 0.01-0.19 mg/L, respectively. The cluster and principal component analysis unveiled the seawater intrusion for freshwater needs was the dominant factor affecting the groundwater. Followed by the dissolution of soil particles surrounds the groundwater table, and the surface run-off by rainfall. In conclusion, the groundwater was affected by geogenic factors as it was not extensively extracted due to movement control order of Covid-19 event. This has provided significant insight for a better management plan in sustaining the groundwater of Pulau Kapas.

Matched MeSH terms: Environmental Monitoring*
Sectional analysis of the pollutant wash-off process based on runoff hydrograph

Alias N, Liu A, Egodawatta P, Goonetilleke A

J Environ Manage, 2014 Feb 15;134:63-9.
PMID: 24463850 DOI: 10.1016/j.jenvman.2013.12.034

The validity of using rainfall characteristics as lumped parameters for investigating the pollutant wash-off process such as first flush occurrence is questionable. This research study introduces an innovative concept of using sector parameters to investigate the relationship between the pollutant wash-off process and different sectors of the runoff hydrograph and rainfall hyetograph. The research outcomes indicated that rainfall depth and rainfall intensity are two key rainfall characteristics which influence the wash-off process compared to the antecedent dry period. Additionally, the rainfall pattern also plays a critical role in the wash-off process and is independent of the catchment characteristics. The knowledge created through this research study provides the ability to select appropriate rainfall events for stormwater quality treatment design based on the required treatment outcomes such as the need to target different sectors of the runoff hydrograph or pollutant species. The study outcomes can also contribute to enhancing stormwater quality modelling and prediction in view of the fact that conventional approaches to stormwater quality estimation is primarily based on rainfall intensity rather than considering other rainfall parameters or solely based on stochastic approaches irrespective of the characteristics of the rainfall event.

Matched MeSH terms: Environmental Monitoring
Advances in paper-based sample pretreatment for point-of-care testing

Tang RH, Yang H, Choi JR, Gong Y, Feng SS, Pingguan-Murphy B, et al.

Crit Rev Biotechnol, 2016 Apr 14.
PMID: 27075621 DOI: 10.3109/07388551.2016.1164664

In recent years, paper-based point-of-care testing (POCT) has been widely used in medical diagnostics, food safety and environmental monitoring. However, a high-cost, time-consuming and equipment-dependent sample pretreatment technique is generally required for raw sample processing, which are impractical for low-resource and disease-endemic areas. Therefore, there is an escalating demand for a cost-effective, simple and portable pretreatment technique, to be coupled with the commonly used paper-based assay (e.g. lateral flow assay) in POCT. In this review, we focus on the importance of using paper as a platform for sample pretreatment. We firstly discuss the beneficial use of paper for sample pretreatment, including sample collection and storage, separation, extraction, and concentration. We highlight the working principle and fabrication of each sample pretreatment device, the existing challenges and the future perspectives for developing paper-based sample pretreatment technique.

Matched MeSH terms: Environmental Monitoring
Fulltext Optimization of Multiple and Multipurpose Reservoir System Operations by Using Matrix Structure (Case Study: Karun and Dez Reservoir Dams)

Heydari M, Othman F, Taghieh M

PLoS One, 2016;11(6):e0156276.
PMID: 27248152 DOI: 10.1371/journal.pone.0156276

Optimal operation of water resources in multiple and multipurpose reservoirs is very complicated. This is because of the number of dams, each dam's location (Series and parallel), conflict in objectives and the stochastic nature of the inflow of water in the system. In this paper, performance optimization of the system of Karun and Dez reservoir dams have been studied and investigated with the purposes of hydroelectric energy generation and providing water demand in 6 dams. On the Karun River, 5 dams have been built in the series arrangements, and the Dez dam has been built parallel to those 5 dams. One of the main achievements in this research is the implementation of the structure of production of hydroelectric energy as a function of matrix in MATLAB software. The results show that the role of objective function structure for generating hydroelectric energy in weighting method algorithm is more important than water supply. Nonetheless by implementing ε- constraint method algorithm, we can both increase hydroelectric power generation and supply around 85% of agricultural and industrial demands.

Matched MeSH terms: Environmental Monitoring
Recent progress in research on PM2.5 in subways

Chang L, Chong WT, Wang X, Pei F, Zhang X, Wang T, et al.

Environ Sci Process Impacts, 2021 May 26;23(5):642-663.
PMID: 33889885 DOI: 10.1039/d1em00002k

Nowadays, PM2.5 concentrations greatly influence indoor air quality in subways and threaten passenger and staff health because PM2.5 not only contains heavy metal elements, but can also carry toxic and harmful substances due to its small size and large specific surface area. Exploring the physicochemical and distribution characteristics of PM2.5 in subways is necessary to limit its concentration and remove it. At present, there are numerous studies on PM2.5 in subways around the world, yet, there is no comprehensive and well-organized review available on this topic. This paper reviews the nearly twenty years of research and over 130 published studies on PM2.5 in subway stations, including aspects such as concentration levels and their influencing factors, physicochemical properties, sources, impacts on health, and mitigation measures. Although many determinants of station PM2.5 concentration have been reported in current studies, e.g., the season, outdoor environment, and station depth, their relative influence is uncertain. The sources of subway PM2.5 include those from the exterior (e.g., road traffic and fuel oil) and the interior (e.g., steel wheels and rails and metallic brake pads), but the proportion of these sources is also unknown. Control strategies of PM mainly include adequate ventilation and filtration, but these measures are often inefficient in removing PM2.5. The impacts of PM2.5 from subways on human health are still poorly understood. Further research should focus on long-term data collection, influencing factors, the mechanism of health impacts, and PM2.5 standards or regulations.

Matched MeSH terms: Environmental Monitoring
Fulltext Association of Physicochemical Characteristics, Aggregate Indices, Major Ions, and Trace Elements in Developing Groundwater Quality Index (GWQI) in Agricultural Area

Harun HH, Kasim MRM, Nurhidayu S, Ash'aari ZH, Kusin FM, Karim MKA

Int J Environ Res Public Health, 2021 04 25;18(9).
PMID: 33923119 DOI: 10.3390/ijerph18094562

The aim of this study was to propose a groundwater quality index (GWQI) that presents water quality data as a single number and represents the water quality level. The development of the GWQI in agricultural areas is vital as the groundwater considered as an alternative water source for domestic purposes. The insufficiency of the groundwater quality standard in Malaysia revealed the importance of the GWQI development in determining the quality of groundwater. Groundwater samples were collected from thirteen groundwater wells in the Northern Kuala Langat and the Southern Kuala Langat regions from February 2018 to January 2019. Thirty-four parameters that embodied physicochemical characteristics, aggregate indicator, major ions, and trace elements were considered in the development of the GWQI. Multivariate analysis has been used to finalize the important parameters by using principal component analysis (PCA). Notably, seven parameters-electrical conductivity, chemical oxygen demand (COD), magnesium, calcium, potassium, sodium, and chloride were chosen to evaluate the quality of groundwater. The GWQI was then verified by comparing the groundwater quality in Kota Bharu, Kelantan. A sensitivity analysis was performed on this index to verify its reliability. The sensitivity GWQI has been analyzed and showed high sensitivity to any changes of the pollutant parameters. The development of GWQI should be beneficial to the public, practitioners, and industries. From another angle, this index can help to detect any form of pollution which ultimately could be minimized by controlling the sources of pollutants.

Matched MeSH terms: Environmental Monitoring
Fulltext Predicting Arsenic (As) Exposure on Human Health for Better Management of Drinking Water Sources

Ahmed MF, Lim CK, Mokhtar MB, Khirotdin RPK

Int J Environ Res Public Health, 2021 07 28;18(15).
PMID: 34360286 DOI: 10.3390/ijerph18157997

Chemical pollution in the transboundary Langat River in Malaysia is common both from point and non-point sources. Therefore, the water treatment plants (WTPS) at the Langat River Basin have experienced frequent shutdown incidents. However, the Langat River is one of the main sources of drinking water to almost one-third of the population in Selangor state. Meanwhile, several studies have reported a high concentration of Arsenic (As) in the Langat River that is toxic if ingested via drinking water. However, this is a pioneer study that predicts the As concentration in the Langat River based on time-series data from 2005-2014 to estimate the health risk associated with As ingestion via drinking water at the Langat River Basin. Several time-series prediction models were tested and Gradient Boosted Tree (GBT) gained the best result. This GBT model also fits better to predict the As concentration until December 2024. The mean concentration of As in the Langat River for both 2014 and 2024, as well as the carcinogenic and non-carcinogenic health risks of As ingestion via drinking water, were within the drinking water quality standards proposed by the World Health Organization and Ministry of Health Malaysia. However, the ingestion of trace amounts of As over a long period might be detrimental to human health because of its non-biodegradable characteristics. Therefore, it is important to manage the drinking water sources to minimise As exposure risks to human health.

Matched MeSH terms: Environmental Monitoring
Microplastics in seawater and zooplankton: A case study from Terengganu estuary and offshore waters, Malaysia

Taha ZD, Md Amin R, Anuar ST, Nasser AAA, Sohaimi ES

Sci Total Environ, 2021 Sep 10;786:147466.
PMID: 33984707 DOI: 10.1016/j.scitotenv.2021.147466

Widespread accumulation and distribution of microplastics at the sea surface raise concerns as the habitat is a feeding ground for zooplankton. As primary consumers, these organisms are closely connected to microplastic input in the marine food chain. Little comparative information currently exists about this problem in estuary and offshore systems. This study investigates microplastic distribution in the surface water and the potential ingestion of microplastics in selected taxonomic groups of zooplankton from the Terengganu Estuary to offshore waters, Malaysia. In the surface water, three types of microplastics were found (fibres, fragments and pellets). Fibres made up the highest percentage, comprising 80.8% and 73.8% of microplastics in offshore waters and estuaries, respectively. The highest total density of microplastics was found in the Terengganu Estuary (545.8 particles m-3). Microplastics sampled from the offshore waters were identified as polyamide, polyethylene, and polypropylene, which possibly originated from secondary microplastic sources. Two types of microplastics were detected in zooplankton: fibres and fragments. Fibres were the most commonly ingested microplastic type in zooplankton collected from offshore waters (94%) and estuaries (77.7%). The average sizes of ingested fibres and fragments were 361.7 ± 226.8 μm and 96.8 ± 28.1 μm, respectively, with a wider range of sizes ingested observed in offshore waters than in estuaries. The concentration of microplastics in seven zooplankton groups varied from 0.01 ± 0.002 particles ind.-1 (Harpacticoida) to 0.2 ± 0.14 particles ind.-1 (Aphragmophora). Notwithstanding the conformity of our results (increased anthropogenic activities led to greater plastic pollution within the estuary), no significant correlation was observed between the levels of microplastic ingestion and microplastic concentration in the surface water within both areas. Our results provide an important baseline reference on microplastic pollution from estuary to offshore waters, as well as proving that zooplankton act as a repository for microplastic in the marine ecosystem.

Matched MeSH terms: Environmental Monitoring
Fulltext Accumulation and depuration of heavy metals in the hard clam (Meretrix meretrix) under laboratory conditions

Wahi Abdul Rashid, Vun, Leong Wan, Mohd Harun Abdullah

Trop Life Sci Res, 2009;20(1):-.
MyJurnal

Heavy metal accumulation and depuration may alter the effectiveness of Meretrix meretrix as a biomonitoring organism for water quality assessment. Therefore, this study was conducted to evaluate the effects of heavy metal accumulation and depuration on M. meretrix, by immersing it in Copper (Cu), Zinc (Zn), and Lead (Pb)
solutions under laboratory conditions. The results showed that M. meretrix is able to accumulate Cu, Zn, and Pb at the rate of 0.99, 21.80, and 0.57 μg/g per day, respectively, and depurates at the rate of 0.42, 23.55, and 1.01 μg/g per day, respectively. These results indicate that M. meretrix could be effectively used as a biomonitoring organism for Cu because the accumulation rate is significantly (p ≤ 0.05) higher than the depuration rate. However, this was not the case for Zn because the accumulation rate was almost similar to the depuration rate, while for Pb, accumulation or depuration did not occur in M. meretrix.

Matched MeSH terms: Environmental Monitoring

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