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Heavy metals contamination in soil is one of the global issues, posing a threat not just to the environment but also to human health. Identifying the source and distribution of heavy metal pollutants around mining areas can provide a scientific basis for future environmental control. Distributions of the heavy metals (Cd, Cr, As, and Ni) in this study were evaluated using descriptive and multivariate statistics and further described using a geostatistical approach and pollution indices. The total content of Cr, Cd, and Ni in surface soil was observed with a higher concentration level according to the Dutch target values and the 95% Investigation Levels determined for Malaysia soil. Statistical analyses, geostatistics, and GIS mapping suggested that Cd, Cr, and Ni were derived mainly from anthropogenic sources, including mining and agricultural activities, while As could be derived from lithogenic and anthropogenic sources. Geoaccumulation index analysis demonstrated that the contamination that occurred with Cd posed the greatest risk of contamination, followed by Cr, Ni, and As. A spatial interpolated map showed a higher concentration of heavy metals in the vicinity of the mining area. These findings highlight the effectiveness of principal component analysis, geostatistics, and geospatial analyses in evaluating heavy metal contents in the study area. The obtained results could be used by authorities to identify areas requiring remediation management and establish scientific baseline data related to soil quality. [ABSTRACT FROM AUTHOR]

An investigation study was conducted in Bukit Merah Reservoir (BMR) for the assessment of arsenic concentration in the surface sediment in 23 sampling stations. The sediment samples were digested and analysed for arsenic using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). Sediment parameters such as pH (4.42 ± 0.71), redox potential (121.77 ± 42.45 mV), conductivity (205.7 ± 64.07 µS cm-1) and organic matter (25.35 ± 9.34%) were also examined. The main objectives of this study are to determine the arsenic distribution and concentration and at the same time to assess the enrichment of arsenic using the geoaccumulation index (Igeo) and enrichment factor (EF). This study shows the total arsenic concentration in the surface sediment of BMR is 4.302 ± 2.43 mg kg-1 and found to be below the threshold value of Canadian Interim Sediment Quality Guidelines (ISQG). High arsenic concentration is recorded near the southern part of the lake where anthropogenic activities are prevalent. Based on Igeo, 13% of sampling stations are categorised as moderately polluted, 52.2% as unpolluted to moderately polluted and the rest is categorised as unpolluted. EF shows 78.3% stations are classified as extremely high enrichment and the rest as very high enrichment. This finding provides important information on the status of arsenic contamination in BMR and creating awareness concerning the conservation and management of the reservoir in the future. [ABSTRACT FROM AUTHOR]

A study was carried out on the distribution and enrichment of trace elements in the core marine sediments of East Malaysia from three stations at South China Sea and one station each at Sulu Sea and Sulawesi Sea. Five stations of sediment cores were recovered and the vertical concentration profiles of six elements namely Br, Cs, Hf, Rb, Ta, and V were determined using the instrumental neutron activation analysis. The enrichment factor, geoaccumulation index and the modified degree of contamination were used to calculate the anthropogenic and pollution status of the elements in the samples. Except for Cs and Hf, which by the enrichment factor are categorized from minimum enrichment to moderate enrichment in all stations and for V and Rb in Sulu Sea and Sulawesi Sea, which are categorized minimum enrichment, other elements are found to be no enrichment at all stations. The geoaccumulation index of Hf in one station shows moderately polluted and for other elements are unpolluted. However, the modified degree values of all samples are less than 1, suggesting very low contamination of elements found in all the stations. [ABSTRACT FROM AUTHOR]

Heavy metal concentrations were examined in 30 soil samples from Gebeng industrial city, Malaysia using inductively coupled plasma-mass spectrometry for As, Ba, Cd, Co, Cr, Cu, Ni, Pb and Zn, and direct mercury analyzer (DMA-80) for Hg. Multivariate statistical techniques including hierarchical cluster analysis (CA), principal component analysis (PCA), correlation analysis and analysis of variance were used to identify the spatial distribution and potential sources of heavy metals. The mean concentrations of heavy metals in the soil samples are in decreasing order as follows: Co > Ba > Zn > As > Pb > Cr > Cu > Ni > Hg > Cd. The Gebeng soils are characterized by high mean relative concentration of As, Ba, Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn in the industrial zone (IZ) than the Kampung-Balok residential area (KB) and submerged area (SA), indicating inputs from industrial activities. Geochemical results suggested that Gebeng soils are primarily polluted by As, Co, Hg, Pb, and Cu subsequently derived from anthropogenic sources. PCA and CA in the heavy metals indicate both anthropogenic and natural origin. However, the geoaccumulation index and pollution load index further confirm the high contamination levels of the heavy metals in IZ and low to uncontaminated in KB and SA regions. [ABSTRACT FROM AUTHOR]

The present study investigates the concentration of Pb, Cd, Ni, Zn, and Cu in the paddy field soils collected from Tumpat, Kelantan. Soil samples were treated with sequential extraction to distinguish the anthropogenic and lithogenic origin of Pb, Cd, Ni, Zn, and Cu. ELFE and oxidizable-organic fractions were detected as the lowest accumulation of Pb, Cd, Ni, Zn, and Cu. Therefore, all the heavy metals examined were concentrated, particularly in resistant fraction, indicating that those heavy metals occurred and accumulated in an unavailable form. The utilization of agrochemical fertilizers and pesticides might not elevate the levels of heavy metals in the paddy field soils. In comparison, the enrichment factor and geoaccumulation index for Pb, Cd, Ni, Zn, and Cu suggest that these heavy metals have the potential to cause environmental risk, although they present abundance in resistant fraction. Therefore, a complete study should be conducted based on the paddy cycle, which in turn could provide a clear picture of heavy metals distribution in the paddy field soils. [ABSTRACT FROM AUTHOR]

Heavy metals bioavailability, organic matter and grain size were investigated in the surface sediment of Sungai Puloh mangrove area using modified sequential extraction technique, loss on ignition and pipette method, respectively. There was elevated level of heavy metals concentration for Cd, Cu, Pb, Zn and Ni as high as 1.46, 202.34, 225.47, 650.83 and 226.90 µg/g, respectively. High organic matter content was also recorded in the range 38.45-46.90%. Particle size analysis revealed that the sediment is sufficiently of clay texture (over 50%). Geoaccumulation index (Igeo), contamination factor (CF), pollution loads index (PLI) and risk assessment code were determined. RAC was as high as 50%. Very strong pollution (Igeo < 3) and high CF (CF > 6) were observed. All sites therefore may be considered polluted (PLI > 1). Discriminant analysis, nonparametric Kruskal-Wallis test as well as principal component analysis (PCA) were conducted. Significant difference for concentration of heavy metals in sediment was obtained (P < 0.05) for Kruskal-Wallis tests. PCA resulted in the extraction of three components (F1, F2 and F3) accounts for 80.04% of the total variation. Anthropogenic as well as natural activities are the sources of pollution in Sungai Puloh. [ABSTRACT FROM AUTHOR]

Sediment can accumulate trace elements in the environment. This study profiled the magnitude of As, Ba, Cd, Co, Cu, Cr, Ni, Pb, Se, and Zn pollution in surface sediments of the west coast of Peninsular Malaysia. Trace elements were digested using aqua regia and were analyzed using the inductively coupled plasma-mass spectrometry. The extent of elemental pollution was evaluated using with the enrichment factor (EF) and geoaccumulation index (I geo ). This study found that the elemental distribution in the sediment in descending order was Zn > Ba > Cr > Pb > Cu > As > Ni > Co > Se > Cd. Zn concentrations in all samples were below the interim sediment quality guideline (ISQG) (124 mg/kg). In contrast, Cd concentrations (2.34 ± 0.01 mg/kg) at Station 31 (Merlimau) exceeded the ISQG (0.70 mg/kg), and the concentrations of As in the samples from Station 9 (Tanjung Dawai) exceeded the probable effect level (41.60 mg/kg). The I geo and EF revealed that Station 9 and Station 31 were extremely enriched with Se and Cd, respectively. All stations posed low ecological risk, except Station 31, which had moderate ecological risk. The outputs from this study are expected to provide the background levels of pollutants and help develop regional sediment quality guideline values. This study is also important in aiding relevant authorities to set priorities for resources management and policy implementation.