Shells that remember: Heavy metals concentrations in Perna Viridis shells from the West coast of peninsular Malaysia

Malaysia is one of the fast economic developing nations in the region. From the ecotoxicological points of view, many environmental concerns are expected to continually rise up due to the potential anthropogenic inputs such as industries and urbanization. Although the heavy metal concentrations had been reported in the sediments from the west coast of Peninsular Malaysia, the east coast receives lesser attention since it is not as populous and industrialized as in the west coast. In this study, concentrations of Cu and Zn for surface sediments were determined and the samples were collected between 2002 and 2004, from west (five sites), south (five sites) and east (10 sites) intertidal area of Peninsular Malaysia. Total Cu concentrations ranged from 3.80 to 117 μg/g dry weight with south coast recording the highest mean concentration (38.8 μg/g dry weight), followed by west (31.13 μg/g dry weight) and east coasts (12.96 μg/g dry weight). Total Zn concentrations ranged from 36.6 to 395 μg/g dry weight with west coast recording the highest mean concentration (137 μg/g dry weight), followed by south (111 μg/g dry weight) and east coasts (73.8 μg/g dry weight). Apart from the comparison based on the conventional total concentrations of metals, three geochemical fractions (EFLE, acid-reducible and oxidisable-organic) were also useful in identifying the polluted sites in which the three geochemical fractions in the sediments of the west and south coasts of Peninsular Malaysia had significantly (P < 0.05) higher concentrations of Cu and Zn when compared to those in the east coastal sediments. This had strengthened our previous assumption that the east coast is less polluted by anthropogenic Cu and Zn when compared to the west and south coasts of Peninsular Malaysia.

Malaysia is one of the fast economic developing nations in the region. From the ecotoxicological points of view, many environmental concerns are expected to continually rise up due to the potential anthropogenic inputs such as industries and urbanization. Although the heavy metal concentrations had been reported in the sediments from the west coast of Peninsular Malaysia, the east coast receives lesser attention since it is not as populous and industrialized as in the west coast. In this study, concentrations of Cu and Zn for surface sediments were determined and the samples were collected between 2002 and 2004, from west (five sites), south (five sites) and east (10 sites) intertidal area of Peninsular Malaysia. Total Cu concentrations ranged from 3.80 to 117 μg/g dry weight with south coast recording the highest mean concentration (38.8 μg/g dry weight), followed by west (31.13 μg/g dry weight) and east coasts (12.96 μg/g dry weight). Total Zn concentrations ranged from 36.6 to 395 μg/g dry weight with west coast recording the highest mean concentration (137 μg/g dry weight), followed by south (111 μg/g dry weight) and east coasts (73.8 μg/g dry weight). Apart from the comparison based on the conventional total concentrations of metals, three geochemical fractions (EFLE, acid-reducible and oxidisable-organic) were also useful in identifying the polluted sites in which the three geochemical fractions in the sediments of the west and south coasts of Peninsular Malaysia had significantly (P &lt; 0.05) higher concentrations of Cu and Zn when compared to those in the east coastal sediments. This had strengthened our previous assumption that the east coast is less polluted by anthropogenic Cu and Zn when compared to the west and south coasts of Peninsular Malaysia.

Heavy metal (Cd, Cu, Pb and Zn) concentrations in the green-lipped mussel Perna viridis (Linnaeus) collected from some wild and aquacultural sites in the west coast of Peninsular Malaysia

Surface sediments and giant mudskipper (Periophthalmodon schlosseri) were collected in August and September 2008 and in March and June 2010 from six sampling sites in the west coast of Peninsular Malaysia to assess heavy metals accumulation in the giant mudskipper. Sequential extraction technique was used to fractionate the sediments into four different geo-chemical fractions; easily, freely or leachable and exchangeable (EFLE), acid reducible, oxidizable organic and resistant fractions. Heavy metals concentrations (Cu, Zn, Pb, Cd and Ni) in the surface sediments and giant mudskipper were determined by using air acetylene flame atomic absorption spectrophotometer (AAS) Perkin Elmer Analyst 800. The results of Pearson’s correlation analyses showed that metal concentrations in the tissues of P. schlosseri were significantly correlated (p p P. schlosseri and Cu in the sediment (oxidisable-organic, resistant and total Cu), Zn in P. schlosseri and Zn in the sediment (EFLE and total Zn), Pb in P. schlosseri and Pb in the sediment (with all the four fractions of Pb), Cd and Ni in P. schlosseri and Cd and Ni in the sediment (with all fractions of Cd and Ni except acid-reducible Cd and Ni) which might suggest the use of P. schlosseri as a biomonitoring agent for heavy metals pollution in the west coast of Peninsular Malaysia.

The present study examined status of heavy metals (Cu, Zn, Pb, Cd and Ni) pollution in the surface sediments of west coast of Peninsular Malaysia. Heavy metals concentrations were determined by using air acetylene flame atomic absorption spectrophotometer (AAS) Perkin Elmer Analyst 800. The results of particle size analysis of the surface sediments indicate high metals concentrations at sampling sites with high content of sand and clay particles. The results of Pearson’s correlation analysis based on the relationship between particle size distribution and total heavy metals, and the relationship between the studied metals (Cu, Zn, Pb, Cd and Ni) revealed significant correlations at (p 5 > 3 > 1 > 6 > 4. The Igeo, EF and PLI values indicate heavy metals contamination in the study area, particularly Pb. Considerable attention should be made at sampling sites that showed higher metals contamination in order to monitor metals pollution and save its biological components from deterioration.

Surface sediments and giant mudskipper (Periophthalmodon schlosseri) were collected in August and September 2008 and in March and June 2010 from six sampling sites in the west coast of Peninsular Malaysia to assess heavy metals accumulation in giant mudskipper. The aim of the present study was to assess heavy metals concentration in giant mudskipper (Periophthalmodon schlosseri) and their correlations with different geochemical fractions of sediments. Sequential extraction technique was used to fractionate the sediments into four different geo-chemical fractions; easily, freely or leachable and exchangeable (EFLE), acid reducible, oxidizable organic and resistant fractions. Heavy metals concentrations (Cu, Zn, Pb, Cd and Ni) in the surface sediments and giant mudskipper were determined by using air acetylene flame atomic absorption spectrophotometer (AAS) Perkin Elmer Analyst 800. The results of Pearson’s correlation analyses showed that metal concentrations in the tissues of P. schlosseri were significantly correlated (p &lt; 0.01 or p &lt; 0.05), correlations were observed between Cu in P. schlosseri and Cu in the sediment (oxidisable organic, resistant and total Cu), Zn in P. schlosseri and Zn in the sediment (EFLE and total Zn), Pb in P. schlosseri and Pb in the sediment (with all the four fractions of Pb), Cd and Ni in P. schlosseri and Cd and Ni in the sediment (with all fractions of Cd and Ni except acid-reducible Cd and Ni) which might suggest the use of P. schlosseri as a biomonitoring agent for heavy metals pollution in the west coast of Peninsular Malaysia.

The present study analyzes and quantifies the spatial–temporal variability of outgoing longwave radiation (OLR) over peninsular Malaysia using the continuous wavelet transform (CWT) from 2003 to 2010. The goal is to understand the long-term variability of OLR over Malaysia in terms of time–frequency variations in relation to the monsoon period and other weather phenomena. The study regions selected were the west coast, east coast, and southern part of peninsular Malaysia. The OLR variation characteristics in time and space derived from wavelet transform were found to be distinctly different in these three regions. In these three regions, OLR showed significant periodicities dominated by the annual cycle, followed by a semiannual cycle. The west coast of peninsular Malaysia has a lower annual component compared to the other regions because of the rain-sheltering effect by the mountain range that blocked the heavy rainfall from northeast monsoon winds. Besides that, the results show that the wet and dry spells coincide with local monsoon and intermonsoon periods. Meanwhile, the results also revealed that the semiannual variation is statistically significant during 2004–06. The strong semiannual variation is coincident with several droughts that resulted from the strong El Niño events in 2004–06. In addition, the phase plot of wavelet coefficients shows that the variations at various scales are in phase, which coincided with the sudden variations of OLR, indicating heavy flood occurrences in the southern part of peninsular Malaysia. The results show that CWT is a powerful tool for analysis of phenomena involving multiscale interactions that exhibit localization in both time and frequency.

The mangrove horseshoe crab,Carcinoscorpius rotundicauda, has divergent populations between the east and west coasts of Peninsular Malaysia, with the southern coast acting as a land barrier. The actual position of such a genetic break along Peninsular Malaysia as well as the connectivity status of the southernmostC. rotundicaudapopulations with east and west coast populations remain unexplored, however.The aim was to investigate the genetic diversity and structure ofC. rotundicaudapopulations from the west (Kuala Sepetang in State Perak), east (Balok in State Pahang), and southern (Pendas in State Johor) coasts of Peninsular Malaysia. Haemolymph samples from adultC. rotundicaudaspecimens (n = 152) and eggs from their freshly deposited nests (n = 190) were collected monthly (from January 2016 to January 2017) for the sequencing of mitochondrial cytochrome coxidase subunit I (COI).Gene isolates ofC. rotundicaudafrom the present study were compared with National Center for Biotechnology Information (NCBI) GenBank sequences to cover most of the range of the species in Asia. A neighbour‐joining tree strongly supported two clades, separating the west‐coast populations from the south‐ and east‐coast populations, with further substructure patterns.Both haplotype network and barrier analyses revealed a genetic break within the Strait of Malacca instead of the southern tip of Peninsular Malaysia. The southernmost samples from the Strait of Johor formed a haplotypic diverse gene pool that appeared only as a subclade of the eastern populations. In a detailed haplotype network of 347 individuals, individuals with similarCOIsequences indicate connectivity betweenC. rotundicaudaon the east andC. rotundicaudaon south and south west of Peninsular Malaysia.Overall, the genetic break betweenC. rotundicaudapopulations is better explained by the convergent ocean currents and available mangrove habitats on the west coast (i.e. Strait of Malacca), rather than the point of the Malay Peninsula acting as a land barrier alone.

Paddy farming activity is in full swing in both east and west coast of Peninsular Malaysia, this was due to rice is a staple food for Malaysian and national food security. This study examined technical efficiency of paddy farming in east and west coast of Peninsular Malaysia by using data envelopment analysis. Besides, this study also attempted to investigate determinants of inefficiency by using Tobit regression. Information was collected through direct survey interview on a sample of 230 paddy farmers from Peninsular Malaysia. Average efficiency scores of paddy farming for the whole of Peninsular Malaysia, east and west coast had been estimated at 55.6, 51.7 and 63.1%, respectively. The variable tractor had been found positively and significantly affected inefficiency in the east coast of Peninsular Malaysia. On the other hand, inefficiency was found significantly and negatively affected by the variable seminar in the west coast. Efficiency performance of west coast in paddy farming was considered better off than the east coast. In brief, both east coast and west coast of Peninsular Malaysia had indicated relatively low efficiency performance. Encouragement of attending seminar in west coast of Peninsular Malaysia for regularly updating new technology and information should be done by authorities in order to improve efficiency performance of paddy farming.

Incidences of hermaphroditism in green mussels (Perna viridis) were determined in four different areas (Sebatu, Port Dickson, Muar and Johor Bahru) along the west coast of Peninsular Malaysia. In Sebatu, 1000 specimens of green mussels were used for the visual determination of sex ratios. The male:female visual ratio was 1:0.79. Three hundred and seventeen individuals were also sexually identified using histology technique. Male to female ratio was 1:1.01. Two hermaphrodite specimens were recorded during the months of June and September, 2004. In Port Dickson, 319 specimens were visually sex-determined, the male: female ratio was 1.00:0.86. One hundred forty one were also histologically identified. Male: female ratio was 1.00:0.96. There was no hermaphrodite specimen encountered in this population. For the population of Muar and Johor Bahru, the entire specimen’s numbers were visually sex-determined first and later confirmed by histological procedure. The male:female ratio was 0.72:1.00 and 1.00:0.95. No hermaphrodite specimen was found at either site. The pooled samples from different months showed no significant seasonal deviation in the sex ratio from a 1:1 ratio (Chi-square test, p>0.05).

Vegetable is an essential daily diet item for the people of Malaysia. This work addressed the radiation and heavy metal exposure scenarios through the consumption of vegetables. Kuala Selangor is located in Sungai Selangor estuary in the west coast of Peninsular Malaysia, which is susceptible to pollution load due to the presence of large-scale industrial and human activities. Radioactivity and heavy metals level in human diet is of particular concern for the assessment of possible radiological and chemical hazards to human health. Therefore, a comprehensive study was carried out to determine the radioactivity levels ((226)Ra, (228)Ra and (40)K) and heavy metal concentrations (Cr, As, Cd, Mn, Mg, Al, Sr, Rb, Sb, Ba, Hg, Fe, Ni, Zn, Cu, Bi and Pb) in 10 varieties of vegetable collected from different farmlands in Kuala Selangor region. The committed doses for (226)Ra, (228)Ra and (40)K due to consumption of vegetables were found 16.6±1.3, 23.6±1.7 and 58±5 µSv y(-1), respectively, with a total of 98±8 µSv y(-1). This dose imposes no significant threat to human health. The estimated cancer risk shows that probability of increase in cancer risk from daily intake of vegetables is only a minor fraction of International Commission on Radiological Protection values. The concentrations of heavy metal were below the daily intake recommended by the international organisations.

Environmental pollution in the form of increased concentration of heavy metal Copper (Cu) becomes the main factor that can affect water quality and inhibit green mussel culture ( Perna viridis ) in Ujung Pangkah Coastal Area of Gresik District. The purpose of this research is to analyze concentration of heavy metal Copper (Cu) on water and its bioaccumulation in green mussel ( P. viridis ) in Ujung Pangkah waters, Gresik District. This research will be conducted from June to August 2017. The method used in this research is descriptive method. Sampling of seawater and mussel by purposive sampling. Cu heavy metal content in Ujung Pangkah waters, Gresik District has 0.003 – 0.006 ppm in July and 0.002 – 0.006 ppm in August. That value is still safe below predetermined quality standards. The results of heavy metal measurement test in shellfish has 0.159 to 0.69 ppm in July and 0.162 – 0.71 ppm in August. The high concentrations of Cu heavy metals in Ujung Pangkah waters are simultaneous to the bioaccumulation concentration in the green mussel. The higher concentration in the waters, the higher the bioaccumulation in the green mussels. And vice versa. The distribution of Cu heavy metal concentration at point 4 is the highest. While at point 1 has the lowest Cu heavy metal concentration. Keywords: Copper, Bioaccumulation, Green Mussel, Heavy Metal, Perna viridis .

Concentrations of Cu and Pb in the offshore and intertidal sediments of the west coast of Peninsular Malaysia

The background levels of heavy metal concentration in sediments of the west coast of Peninsular Malaysia

Subtropical meiobenthic nematode communities in Victoria Harbour, Hong Kong