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  1. Suresh Raj PR, Mohan Viswanathan P
    Chemosphere, 2023 Mar;316:137838.
    PMID: 36642142 DOI: 10.1016/j.chemosphere.2023.137838
    In this study, estuarine water samples were collected at diverse hot spots in Miri River Estuary, East Malaysia to appraise the geochemical processes, which controls the river water quality. The collected water samples were analysed for various physicochemical parameters (insitu parameters, nutrients, major ions and trace metals), including stable isotopes (oxygen and hydrogen). Suspended solids are also extracted from the water samples and analysed for trace metals. Standard graphs, Piper plot, Gibbs diagram, water quality indices, geochemical modelling and statistical analysis were used for the data analysis. The acquired water quality data was compared with national and international guidelines for the suitability of water for various purposes. Interpretation of data reveals that the estuarine water quality is deemed unsuitable to be used for both drinking and irrigation purposes. Overall, the elemental concentrations are increasing from downstream to river mouth. Based on pollution indices (HEI and Cd), downstream region shows high vulnerability to metal pollution due to anthropogenic disturbance. Isotope values of river water indicate direct atmospheric precipitation with minimal evaporation. Factor analysis reveals that seawater influx, urban pollution, domestic and agricultural discharges at the downstream region are the main controlling factors to the river water quality. It is also deduced that suspended solids play a vital role in the adsorption and desorption of trace metals in the estuarine water. The outcome of this study provides a comprehensive information on pollution status of Miri estuary, which helps the policy makers to practice sustainable management of this water resource for Miri community.
  2. Nyambar INA, Mohan Viswanathan P
    Environ Sci Pollut Res Int, 2024 Jun;31(29):41306-41328.
    PMID: 36650369 DOI: 10.1007/s11356-023-25172-9
    The main purpose of this study is to assess the urban lake water quality along the coastal region of Miri City, Sarawak, East Malaysia. This study concentrates on the hydrochemical characteristics and the mechanisms controlling the suitability of the lakes for domestic, irrigation, and industrial purposes. A total of 15 lake water samples were collected and analysed for physical parameters, major ions, nutrients, BOD, COD, and heavy metals. The results show that Lakes 6, 7, and 8 commonly exceeded the National Drinking Water Quality Standards (NDWQS) limits, particularly in physical parameters and major ions. The cation dominance was Na+  > Mg2+  > K+  > Ca2+, while the anion dominance was Cl-  > HCO3-  > SO42-. It is inferred that lake 8 was affected by the seawater intrusion through the inlet flow, resulting in an excess concentration of ions present in that lake. The concentrations of heavy metals in these lakes were considerably low, indicating that most of them were from the geogenic source. Most of the lakes were NaCl water type and the main controlling mechanism were weathering and ionic exchange processes, with anthropogenic impacts. Based on the calculated Water Quality Index (WQI) according to the National Water Quality Standards (NWQS), all lakes were suitable for irrigation use (class IV), while most of these lakes fell under the "polluted" index. Apart from that, based on the National Lake Water Quality Standards (NLWQS), all lakes were classified under category D, indicating that the lakes must be kept in good condition. According to the irrigation quality indices, lakes 1, 2, 3, 4, and 5 were the most suitable for irrigation purposes. As for metal pollution indices (HPI and HEI), lakes 1, 2, 3, 4, 5, and 15 were considered safe with low pollution status. From the multivariate statistical analysis, it is deduced that both anthropogenic and geogenic impacts mostly influenced the quality of these lake waters. The outcome of this study will help the policymakers under the national water department in sustainable management of water resources in this region.
  3. Ima-Nirwana S, Merican Z, Jamaluddin M, Viswanathan P, Khalid BA
    Asia Pac J Clin Nutr, 1996 Jun;5(2):100-4.
    PMID: 24394519
    The atherogenic potential of soybean oil (Sb) and palm oil (PO) was compared by measuring lipid profile, lipid peroxidation (LP) and activity of the antioxidant enzyme glutathione peroxidase (GSHPx) in rat sera and liver and heart homogenates. Male Rattus norwegicus rats were fed a basal diet, or basal diet fortified with 20% weight/ weight Sb or PO for 4 or 9 months. There was no difference in high density lipoprotein cholesterol:low density lipoprotein cholesterol ratio between the two groups, but triglyceride concentrations were higher in the PO fed rats compared to the Sb fed rats, although the difference diminished after 9 months. No differences in serum LP and GSHPx activity were seen between the two groups. In the liver and heart, LP was lower in PO after 4 months feeding, but the reverse was seen after 9 months. Liver and heart GSHPx activity was higher in the PO group after both treatment periods. In conclusion, both PO and Sb fed rats appeared comparable in their lipid profile, but the PO food had a temporary beneficial effect on the LP process in liver and heart. GSHPx activity however did not correlate well with LP in liver and heart, suggesting involvement of other antioxidants.
  4. Mohan Viswanathan P, Sabarathinam C, Karuppannan S, Gopalakrishnan G
    Environ Dev Sustain, 2022;24(6):8856-8882.
    PMID: 34393622 DOI: 10.1007/s10668-021-01719-z
    This study aims to explore the state-wise assessment of SARS-CoV-2 (COVID-19) pandemic spread in Malaysia with focus on influence of meteorological parameters and air quality. In this study, state-wise COVID-19 data, meteorological parameters and air quality index (AQI) were collected from March 13 to April 30, 2020, which encompass three movement control order (MCO) periods in the country. Overall, total infected cases were observed to be higher in MCO phase 1 and 2 and significantly reduced in MCO phase 3. Due to the variation in the spatial interval of population density and individual immunity, the relationship of these parameters to pandemic spread could not be achieved. The study infers that temperature (T) between 23 and 25 °C and relative humidity (RH) (70-80%) triggered the pandemic spread by increase in the infected cases in northern and central Peninsular Malaysia. Selangor, WP Kuala Lumpur and WP Putrajaya show significantly high infected cases and a definite trend was not observed with respect to a particular meteorological factor. It is identified that high precipitation (PPT), RH and good air quality have reduced the spread in East Malaysia. A negative correlation of T and AQI and positive correlation of RH with total infected cases were found during MCO phase 3. Principal component analysis (PCA) indicated that T, RH, PPT, dew point (DP) and AQI are the main controlling factors for the spread across the country apart from social distancing. Vulnerability zones were identified based on the spatial analysis of T, RH, PPT and AQI with reference to total infected cases. Based on time series analysis, it was determined that higher RH and T in Peninsular Malaysia and high amount of PPT, RH and good air quality in East Malaysia have controlled the spreading during MCO phase 3. The predominance of D614 mutant was observed prior to March and decreases at the end of March, coinciding with the fluctuation of meteorological factors and air quality. The outcome of this study gives a general awareness to the public on COVID-19 and the influence of meteorological factors. It will also help the policymakers to enhance the management plans against the pandemic spreading apart from social distancing in the next wave of COVID-19.

    SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10668-021-01719-z.

  5. Seow SQ, Mohan Viswanathan P, Dodge-Wan D
    Environ Sci Pollut Res Int, 2024 Jun;31(30):43292-43308.
    PMID: 38902441 DOI: 10.1007/s11356-024-33906-6
    Labuan, Miri, Kundasang and Raub regions of Malaysia have very different geological formations and settings that could result in different levels of natural radioactivity. Hence, this study determines the influence of different geological formations on radioactivity in these locations using field measurements, petrology and geochemistry. A total of 141 gamma dose rates and 227 beta flux measurements were collected using Polimaster survey meters (PM1405) in these four regions. The gamma dose rate values range from 0.37 to 0.05 µSv/h with a mean value of 0.11 µSv/h. Beta flux values range from 3.46 to 0.12 CPS with a mean value of 0.57 CPS. Mineralogy and elemental composition of the different rock types were analysed using thin-section petrography, XRD, ICP and pXRF methods. Felsic igneous rocks such as syenite and granite have higher natural radioactivity and contain more radionuclide-bearing minerals such as apatite, zircon, allanite, K-feldspar, titanite, muscovite and biotite. Metamorphic rocks have the second highest natural radioactivity and contain fewer radioactive minerals. The natural radioactivity of sedimentary rocks mostly depends on their clay content. The gamma dose rate maps show that igneous and metamorphic regions around Raub have higher radioactivity compared to the sedimentary-dominated regions around Miri and Labuan. Annual effective dose (AED) and excess lifetime cancer risk (ELCR) were calculated to evaluate the potential health risk for inhabitants of these regions. Labuan and Miri are considered to be safe zones with respect to natural radioactivity as the results show little to no risk for the public, compared with the Raub region, which is medium to high risk.
  6. Mishra A, Mohan Viswanathan P, Ramasamy N, Panchatcharam S, Sabarathinam C
    Environ Sci Pollut Res Int, 2023 Oct;30(46):103225-103243.
    PMID: 37688695 DOI: 10.1007/s11356-023-29582-7
    The current study aims to investigate the spatiotemporal distribution of microplastics (MPs) in the Miri coast, targeting their occurrences, characterisation, and potential sources. For a periodical study, coastal sediments were collected from three different time intervals (monsoon, post-monsoon, and post-COVID) and subjected to stereomicroscope, ATR-FTIR, and SEM-EDX analyses. These results show a significant increase of MPs in post-COVID samples by approximately 218% and 148% comparatively with monsoon and post-monsoon samples, respectively. The highest concentration of MPs was detected near the river mouths and industrial areas where the waste discharge rate and anthropogenic activities dominate. Fibre-type MPs are the most abundant, with an average of nearly 64%, followed by fragments, films, microbeads, and foams. The most dominant polymer types were polytetrafluoroethylene (PTFE), polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyester (PET). Overall, the current study shows a better understanding of MPs occurrence and potential sources in the Miri coastal area.
  7. Gantayat RR, Mohan Viswanathan P, Ramasamy N, Sabarathinam C
    Environ Sci Pollut Res Int, 2023 Aug;30(40):92692-92719.
    PMID: 37495801 DOI: 10.1007/s11356-023-28596-5
    A comprehensive geochemical study was conducted in the Sibuti River estuary by considering water, suspended solids (SS), and sediment samples from 36 stations during southwest monsoon (SWM) and northeast monsoon (NEM). In this study, the distribution of in situ parameters, major ions, nutrients, trace metals, and isotopes (δD, δ18O) were analyzed in water samples, whereas sediments and SS were studied for trace metals. The distribution revealed that suspended solids were the major carrier of Cd, Zn, and Mn, whereas sediments worked as a major source of Co, Cr, Ba, Se, Cu, and Pb. Na-Cl water type and ion exchange dominated the lower part of the estuary during both seasons. However, the mixed mechanism of Ca-Cl, Ca-Mg-Cl, and higher weathering indicated reverse ion exchange in the intermediate and upper parts of the estuary. Isotopic signatures of δD and δ18O in estuarine water indicate that the precipitation over the Limbang area dominates during SWM, whereas higher evaporation was confirmed during NEM. The factor analysis revealed that seawater influence in the estuary majority controlled the water chemistry irrespective of seasons. Major ions were mainly regulated by the tidal influence during the low flow time of the river (SWM), whereas the mixing mechanism of weathering and seawater controlled the concentrations during NEM. Nutrients such as NO3, SO42-, NH3, and NH4+ mainly originated from the agricultural fields and nitrification along with ammonification were responsible for the recycling of such nutrients. Trace metals except Cd were found to be geogenic in nature and originating mainly from the oxidation of pyrites present in the sandstone and mudstones of the Sibuti Formation. Redox condition was catalyzed by microorganisms near the river mouth, whereas Al-oxyhydroxides and Fe-oxyhydroxides complexes in the intermediate and upper part under oxygenated conditions controlled the absorption of metals. Overall, the estuary was found to be absorptive in nature due to ideal pH conditions and was confirmed by the saturation index (SI) of minerals.
  8. Mohan Viswanathan P, Mishra A, Singam DR, John J
    J Environ Manage, 2024 Sep;368:122207.
    PMID: 39180824 DOI: 10.1016/j.jenvman.2024.122207
    Mountain salts produced from the highland region in NE Sarawak have a market value and also provide basic income to the communities. During the salt-making process, microplastics (MPs) may enter into commercial table salts from various sources, which has not been explored yet. Hence, the current research investigates the presence of MPs in the rock salts produced from the highland saline water in two different locations (L1 and L2) in NE Sarawak. Among the brine water and rock salt samples analysed, the highest concentrations of MPs were detected from the salt samples. It has been revealed that both the water and salt samples have the highest concentration of MPs occurring within the size range of 1-1000 μm. Transparent MPs are the most common colour observed in both salt and water samples, followed by white, blue, red, and black. The most prevalent shapes of MPs are fibers, which account for almost 47% in water samples and 87% in salt samples. Based on the ATR-FTIR study, polyethylene (PE) is the most prevalent polymer observed in salt samples, followed by polypropylene (PP), polystyrene (PS), and polyethylene terephthalate (PET). In water samples, PP is the most dominating polymer, followed by PE and PS. Through SEM microphotographs, fiber-type MPs have smooth surfaces, fragment-type MPs have rough edges, and sheet-type MPs have layered surfaces. EDX analysis revealed that carbon (C) and oxygen (O) are the most abundant elements, followed by aluminium (Al) and sodium (Na) in MPs. Based on the results, it is inferred that the MPs in the rock salts are mainly sourced from the different stages of salt-making production. This preliminary study shed light on the presence and characteristics of MPs in rock salts in this region. The research outcomes could support sustainable management plans to improve the salt quality and enhance the market value.
  9. Mathivanan M, Sabarathinam C, Mohan Viswanathan P, Senapathi V, Nadesan D, Indrani GG, et al.
    Environ Res, 2022 Jan;203:111791.
    PMID: 34333012 DOI: 10.1016/j.envres.2021.111791
    Uranium (U) in groundwater is hazardous to human health, especially if it is present in drinking water. The semiarid regions of southern India chiefly depend on groundwater for drinking purposes. In this regard, a comprehensive sampling strategy was adopted to collect groundwater representing different lithologies of the region. The samples were collected in two different seasons and analysed for major and minor ions along with total U in the groundwater. Two samples during pre monsoon (PRM) and seven samples during post monsoon (POM) had U > 30 μgL-1, which is above the World Health Organization's provisional guideline value. The high concentration of U (188 μgL-1) was observed in the alluvial formation though a few samples showed the release of U near the pink granite (39 μgL-1) and the concentration was low in the lateritic formation (10 μgL-1). The uranyl carbonato complexes UO2(CO3)22- and UO2(CO3)34- were associated with high pH which facilitated the transport of U into groundwater especially during POM. U3O8 is the major form observed in groundwater compared to either UO2 or UO3 in the both seasons. The uranium oxides were observed to be more prevalent at the neutral pH. Though U concentration increases with pH, it is mainly governed by the redox conditions. The principal component analysis (PCA) analysis also suggested redox conditions in groundwater to be the major process facilitating the U release mechanism regardless of the season. The POM season has an additional source of U in groundwater due to the application of nitrogenous fertilizers in the alluvium region. Furthermore, redox mobilization factor was predominantly observed near the coastal region and in the agricultural regions. The process of infiltration of the fertilizer-induced U was enhanced by the agricultural runoff into the surface water bodies in the region. Health risk assessment was also carried out by determining annual effective dose rate, cancer mortality risk, lifetime average daily dose and hazard quotient to assess the portability of groundwater in the study area. Artificial recharge technique and reducing the usage of chemical based fertilizers for irrigation are suggested as sustainable plans to safeguard the vulnerable water resource in this region.
  10. Sabarathinam C, Mohan Viswanathan P, Senapathi V, Karuppannan S, Samayamanthula DR, Gopalakrishnan G, et al.
    PMID: 35028838 DOI: 10.1007/s11356-021-17481-8
    The study aims to determine the impact of global meteorological parameters on SARS-COV-2, including population density and initiation of lockdown in twelve different countries. The daily trend of these parameters and COVID-19 variables from February 15th to April 25th, 2020, were considered. Asian countries show an increasing trend between infection rate and population density. A direct relationship between the time-lapse of the first infected case and the period of suspension of movement controls the transmissivity of COVID-19 in Asian countries. The increase in temperature has led to an increase in COVID-19 spread, while the decrease in humidity is consistent with the trend in daily deaths during the peak of the pandemic in European countries. Countries with 65°F temperature and 5 mm rainfall have a negative impact on COVID-19 spread. Lower oxygen availability in the atmosphere, fine droplets of submicron size together with infectious aerosols, and low wind speed have contributed to the increase in total cases and mortality in Germany and France. The onset of the D614G mutation and subsequent changes to D614 before March, later G614 in mid-March, and S943P, A831V, D839/Y/N/E in April were observed in Asian and European countries. The results of the correlation and factor analysis show that the COVID-19 cases and the climatic factors are significantly correlated with each other. The optimum meteorological conditions for the prevalence of G614 were identified. It was observed that the complex interaction of global meteorological factors and changes in the mutational form of CoV-2 phase I influenced the daily mortality rate along with other comorbid factors. The results of this study could help the public and policymakers to create awareness of the COVID-19 pandemic.
  11. Raman R, Nair VK, Shivdas A, Bhukya R, Viswanathan PK, Subramaniam N, et al.
    Heliyon, 2023 Aug;9(8):e18510.
    PMID: 37576319 DOI: 10.1016/j.heliyon.2023.e18510
    Non-financial reporting (NFR) has become crucial to corporate sustainability strategies as companies demonstrate their commitment to the environmental, social, and governance actions outlined in the United Nations Sustainable Development Goals (SDGs) Agenda 2030. Among the various mandatory NFR initiatives, Sustainability Reporting (SR) has emerged as a widely adopted practice by companies worldwide. A gap that the study addresses is the theoretical perspectives on SR in the context of SDG. Then we conduct a bibliometric and science mapping analysis of research trends on SR and precisely map SR research to SDGs which is also a gap in the current literature. We find an exponential increase in the number of publications and citations on SR, particularly after 2015, which coincides with increased public awareness and scrutiny of the SDGs. At the country level, Australia leads with a total of 13 SDGs, followed by the UK, Spain, and Italy, which each address 12 SDGs. Emerging economies such as Indonesia, Malaysia, and India have also increased their contributions since 2019. A keyword co-occurrence analysis identified three main clusters: stakeholder engagement, corporate governance, and accountability; sustainable development goals and climate change; and sustainability reporting and global reporting initiatives. All three clusters had highly cited publications related to SDG 8 (decent work), SDG 9 (industry innovation), and SDG 12 (responsible consumption). This highlights the interdisciplinary nature of SR and its relevance to multiple SDGs. The study is distinctive in that we utilized social network analysis to examine the SDG network based on SR publications, which also affirmed the centrality of SDG 9 and 12. We utilized the prominence percentile, which indicates the momentum of a particular topic, to identify future topics in SR that align with the SDGs. These include cause-related marketing, environmentally preferable purchasing decisions, environmental management systems, education for sustainability, and green computing.
  12. Solomon SD, Ostrominski JW, Vaduganathan M, Claggett B, Jhund PS, Desai AS, et al.
    Eur J Heart Fail, 2024 Jun;26(6):1334-1346.
    PMID: 38733212 DOI: 10.1002/ejhf.3266
    AIMS: To describe the baseline characteristics of participants in the FINEARTS-HF trial, contextualized with prior trials including patients with heart failure (HF) with mildly reduced and preserved ejection fraction (HFmrEF/HFpEF). The FINEARTS-HF trial is comparing the effects of the non-steroidal mineralocorticoid receptor antagonist finerenone with placebo in reducing cardiovascular death and total worsening HF events in patients with HFmrEF/HFpEF.

    METHODS AND RESULTS: Patients with symptomatic HF, left ventricular ejection fraction (LVEF) ≥40%, estimated glomerular filtration rate ≥ 25 ml/min/1.73 m2, elevated natriuretic peptide levels and evidence of structural heart disease were enrolled and randomized to finerenone titrated to a maximum of 40 mg once daily or matching placebo. We validly randomized 6001 patients to finerenone or placebo (mean age 72 ± 10 years, 46% women). The majority were New York Heart Association functional class II (69%). The baseline mean LVEF was 53 ± 8% (range 34-84%); 36% of participants had a LVEF <50% and 64% had a LVEF ≥50%. The median N-terminal pro-B-type natriuretic peptide (NT-proBNP) was 1041 (interquartile range 449-1946) pg/ml. A total of 1219 (20%) patients were enrolled during or within 7 days of a worsening HF event, and 3247 (54%) patients were enrolled within 3 months of a worsening HF event. Compared with prior large-scale HFmrEF/HFpEF trials, FINEARTS-HF participants were more likely to have recent (within 6 months) HF hospitalization and greater symptoms and functional limitations. Further, concomitant medications included a larger percentage of sodium-glucose cotransporter 2 inhibitors and angiotensin receptor-neprilysin inhibitors than previous trials.

    CONCLUSIONS: FINEARTS-HF has enrolled a broad range of high-risk patients with HFmrEF and HFpEF. The trial will determine the safety and efficacy of finerenone in this population.

  13. Solomon SD, McMurray JJV, Vaduganathan M, Claggett B, Jhund PS, Desai AS, et al.
    N Engl J Med, 2024 Oct 24;391(16):1475-1485.
    PMID: 39225278 DOI: 10.1056/NEJMoa2407107
    BACKGROUND: Steroidal mineralocorticoid receptor antagonists reduce morbidity and mortality among patients with heart failure and reduced ejection fraction, but their efficacy in those with heart failure and mildly reduced or preserved ejection fraction has not been established. Data regarding the efficacy and safety of the nonsteroidal mineralocorticoid receptor antagonist finerenone in patients with heart failure and mildly reduced or preserved ejection fraction are needed.

    METHODS: In this international, double-blind trial, we randomly assigned patients with heart failure and a left ventricular ejection fraction of 40% or greater, in a 1:1 ratio, to receive finerenone (at a maximum dose of 20 mg or 40 mg once daily) or matching placebo, in addition to usual therapy. The primary outcome was a composite of total worsening heart failure events (with an event defined as a first or recurrent unplanned hospitalization or urgent visit for heart failure) and death from cardiovascular causes. The components of the primary outcome and safety were also assessed.

    RESULTS: Over a median follow-up of 32 months, 1083 primary-outcome events occurred in 624 of 3003 patients in the finerenone group, and 1283 primary-outcome events occurred in 719 of 2998 patients in the placebo group (rate ratio, 0.84; 95% confidence interval [CI], 0.74 to 0.95; P = 0.007). The total number of worsening heart failure events was 842 in the finerenone group and 1024 in the placebo group (rate ratio, 0.82; 95% CI, 0.71 to 0.94; P = 0.006). The percentage of patients who died from cardiovascular causes was 8.1% and 8.7%, respectively (hazard ratio, 0.93; 95% CI, 0.78 to 1.11). Finerenone was associated with an increased risk of hyperkalemia and a reduced risk of hypokalemia.

    CONCLUSIONS: In patients with heart failure and mildly reduced or preserved ejection fraction, finerenone resulted in a significantly lower rate of a composite of total worsening heart failure events and death from cardiovascular causes than placebo. (Funded by Bayer; FINEARTS-HF ClinicalTrials.gov number, NCT04435626.).

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