Trace metals and rare earth elements in Rock Oyster Saccostrea cucullata along the east coast of Peninsular Malaysia

Trace metals and rare earth elements (REEs) in the soft tissue of rocky shore Rock Oyster, Saccostrea cucullata, along the east coast of Peninsular Malaysia were determined. Significant inter-spatial variations ( p < 0.05) in trace metals and REEs were recorded. Significant positive correlations ( p < 0.01) were found among REEs concentrations. A few significant correlations were found for trace metals and REEs. Average distribution of metals indicated that Johor State had the highest concentrations compared with Pahang and Terengganu for all metals, except for Pb and Cu. This could most likely be attributed to the highly urbanized and industrialized activities such as sewage discharge. The metal accumulation patterns in the oyster indicated enrichment of essential metals. Sites with relatively high concentrations of the contaminant metals Hg, Cu, Pb and Zn were related to their close proximity to industrial and urban sites or to boating and aquaculture activities. Relative enrichment of Cu, Pb and Zn in oysters in the whole study even from relatively pristine areas is thought to be derived from natural sources as these metals are significantly correlated to REEs distribution. The distribution of REEs show close similarity between all sampling sites, suggesting that they are of similar origins. In all sites, typical saw-tooth chondrite-normalized patterns were observed, which strongly suggested the REEs bioaccumulated in oyster tissues is derived from geogenic sources. Typical deviations from this pattern were found for Ce and Eu and could be explained by their redox chemistry. Results of light to heavy REEs (LREE/HREE) ratios suggested REEs fractionation in coastline marine environment produced more light REEs and less heavy REEs absorbed in the soft tissue of S. cucullata. The ratio of La/Yb in the oyster of 27.3 was remarkably similar to Terengganu River basin soil of 33.0 and to Terengganu River sediment of 27.6. Comparison of metal concentration with maximum permissible limits of toxic metals in food established in different countries, as well as Malaysian Food Act 1983 and Food Regulations 1985 Fourteen Schedule, indicated values were well within safety levels, except for Cu and Zn. Along with its wide distribution on rocky shore areas along the east coast, the present results of trace metals and REEs recorded in soft tissue of S. cucullata collected from 14 sites along the east coast of Peninsular Malaysia served as baseline data for future reference

The recovery of microplastics from rock oysters using digestion method

The widespread deposition of microplastics (<5.0 mm) in the marine environment have appeared to be pervasive across the globe. It has led to major attention of many researchers to study this problem. Despite the amount of work conducted to understand these infamous microplastics, there is still no standard procedure for microplastics extraction from marine organism samples. This study investigated three types of digestion treatments; (1) KOH, (2) KOH/H2O2, and (3) KOH/NaClO, followed by density separation using 50% KI to extract the spiked microplastics from the rock oyster. Each treatment was tested to study the digestion effectiveness of the organic soft tissue materials while preserving the microplastic particles. Aside from recovering the spiked microplastics, other small contaminants have been detected in each treatment. All the spiked microplastics and the contaminants obtained were analysed using microscope and FTIR for characterisation. From this study, it was observed that each treatment resulted in high microplastics recovery. Among the three treatments, using 10% KOH alone provided the highest digestion rate, but it required more time to digest the oyster soft tissue. The contaminants detected in the oyster suggested the possibility of microplastics accumulation in non-digestion organs through adherence

Elimination and kinetics of ammonium Ions from waste water using by Zeolite (NaY) preparing from agriculture waste

Zeolite NaY prepared by ash from rice husk used for elimination of ammonium from aqueous solutions. Its performance investigation was compared with natural zeolite granulated formed and powdered mordenite. Natural zeolite mordenite and prepared Zeolite NaY were characterized by Energy Dispersive X-ray (EDX), X-ray Diffraction (XRD) and total cation exchange capacity (CEC) was measured. Measured cation exchange capacity (CEC) of zeolite NaY was 3.15 meq g-1, powdered mordenite was 1.46 meq g-1 and granular mordenite 1.34 meq g-1. Kinetics of adsorption and for the deletion of NH4+ ions of equilibrium data from aqueous solutions were examined by fitting the investigational data to various models of reaction order. NH4+ adsorption on zeolite NaY and mordenite powder followed Pseudo-second-order reaction kinetically. Compared to all isotherms equations, the equilibrium pattern fits well to the Langmuir isotherm equation. The adsorption capacity of the monolayer for powdered mordenite 14.99 mg g- and granular mordenite 13.56 mg g- to be very lower than that zeolite Y was found 43.25 mg g-. Compared to natural mordenite, it can be concluded that zeolite Y synthesized from ash husk is a better sorbent for ammonia removal from aqueous solutions predicted to its higher adsorption capacity and rapid adsorption rate

Determination of some toxic elements such as arsenic, selenium, chromium and lead using icp-ms and gf-aas in rural ground water in Terengganu, Malaysia

ABSTRACT The concentrations of some toxic elements Arsenic (As), Selenium (Se), Lead (Pb) and Chromium (Cr) etc in rural groundwater in Terengganu, Malaysia were determined using most sophisticated instrument ICP-MS and GF-AAS. Most of the populations of Terengganu live in rural area and they use ground water surviving their life. Obtained results are compared with WHO and interim water quality guideline. The determination of heavy and toxic elements in drinking water was obtained by elemental analysis techniques such as inductively coupled plasma mass spectrometry (ICP-MS) and graphite furnace atomic absorption spectrometry (GF-AAS). Groundwater samples were taken from different districts of Terengganu. Most importantly, ICP-MS has recently been described as a very sensitive, multi-element technique. Detection limits obtained by GF-AAS for heavy and trace metals such as Cr and Pb are 1.15 and 3.21 g L -1 respectively, and detection limits obtained by ICP-MS for As, Se and Pb are 8.3, 18 and 0.22 g L-1 respectively. Obtained results showed that all samples got high concentration of lead (Pb) but does not exceed the WHO and Malaysian standards. Keywords: toxic elements, groundwater, detection limits, ICP-MS, GF-AA

Trace metals in Thais clavigera along coastal waters of the East Coast of Peninsular Malaysia

The selected trace metals in the soft tissue of Thais clavigera from 11 sampling sites along the coastal waters of the east coast of Peninsular Malaysia were studied. Significant inter-spatial variations in trace metals were recorded. Sites with relatively high concentrations of the contaminant metals Hg, Cd, Pb and Zn are correlated to their close proximity to industrial and urban sites or to boating and aquaculture activities. This could possibly be contributed by the high growth of industrial activities like port and sewage release. Interspatial comparison with previous studies indicated lower measurement. Meanwhile, comparison with other studies around the world also designated lower values except for Zn. The metal accumulation patterns indicated an enrichment of essential metals over non-essential metals. Comparison of metal concentration with maximum permissible limits of toxic metals in food established in different countries, as well as Malaysian Food Act 1983 and Food Regulations 1985 Fourteen Schedule, indicated the values were well within safety levels

An artificial neural network approach on catering premises inspection in Pahang state

Background: The hygiene level of the premise reflect the safety and quality of the food served in the food services kitchen and the poor sanitary condition can contribute to food poisoning outbreaks. Recently, many food poisoning cases reported from food services sector and most of the cases are from institutional food services. These premises sometimes are graded as clean or very clean which can be questioned, mostly at institutions such as schools. Objective; The aim of this research is to identify the level of significance among the contributing factors which influence the caterers’ grading score in Pahang as the biggest state in Malaysian Peninsular using artificial neural network (ANN). Methods: In this research, the premises have been categorised into 3 categories namely Rest and Rescue Area (RnR) premises along the East Coast Highway, event caterers and institutional. A total of 268 premises were involved in this research with 66 (24.63%) RnR, 63 (23.51%) event caterers, and 139 (51.87%) institutional caterers. The instrument used in this research is based on the official risk based premise inspection form currently used by Ministry of Health Malaysia (MOH). The important items in the inspection form are process control, building and facilities, equipment and utensils, cleaning and maintenance, as well as food handler’s requirements. These items consist a total of thirty-one (31) elements with respected weightage score based on risk to food safety. The collected data is analysed using two-layer neural network with tansig-linear configurations, with trainlm activation function. Results: Prior to data normalization, the dataset is partitioned according 70-30-30 sets. In this research, the final model is reliable where the relative error of the training set is 0.076. The five most significant factors influencing the premises grades are critical control points (CCP), transportation condition, risky other related activity, adequate toilets, as well as adequate and safe water supply. Conclusion: As a conclusion, it is expected that the results will assist the related authorities to take appropriate actions prior to the important and compliance information, especially the significant aspects with respect to public health, permit, inspection and other related legal issues. It is suggested that the result can be improved by using other type of training functions such trainscg and trainbfg