1,721,032 research outputs found
Distributions of heavy metal concentrations in different tissues of the mangrove snail nerita lineata
No full textThis study focused on the distributions of Cd, Cu, Fe, Ni, Pb and Zn in the various tissues (shell, operculum, muscle, digestive cecum, foot, cephalic tentacles, mantle, radular and remainder) of the mangrove snail nerita lineata collected from Sungai Janggut, Selangor. Copper and Zn levels in all soft tissues were found to exceed those in the sediment, indicating bioaccumulation of these metals. Fe levels in all soft tissues of the snails were found to be lower than those in the sediment even though Fe is the most abundant metal among the six metals investigated. Cd and Pb levels in
soft tissues were also found to be lower than those in the sediment but opposite trends were observed for Cd and Pb levels in the shells. Ni, Cd and Pb levels in the shells were significantly (p< 0.05) higher than those in the soft tissues and sediment. However, digestive cecum and remainder showed higher Ni level as compared with sediment. The biota sediments accumulation factor (BSAF) has identified that the shell and operculum were macroconcentrators for Cd, Ni and Pb while all the soft tissues of n. lineata were macroconcentrators for Cu (except for muscle) and Zn. The findings indicated that the differences in metal distribution could be attributed to the differences in tissue physiology and metal handling, storage and detoxification strategies
Heavy metal concentrations in ceiling fan dusts sampled at schools around Serdang area, Selangor
No full textIn this study, ceiling fan dust samples were collected from three schools in the district of Serdang Selangor, Malaysia. The sampled dust were analysed for the concentrations of Cd, Cu, Fe, Ni, Pb and Zn. The heavy metal ranges found in all the schools were 2.96-7.74 ?g/g dry weight for Cd, 75-442 ?g/g dry weight for Cu, 3445-3852 ?g/g dry weight for Fe, 24-66 ?g/g dry weight for Ni, 140-734 ?g/g dry weight for Pb and 439-880 ?g/g dry weight for Zn. SMK Seri Serdang School was found to have elevated concentrations of Cd, Cu, Ni, Pb, and Zn which indicated the anthropogenic sources of the study sites. In comparison to other reported studies in the literature, the maximum levels of Cd, Cu, Ni, and Pb were comparable or higher to those cities reported. Therefore, more monitoring studies should be conducted in future since dusts could be related to human health hazards and the dusts can be used as a potential monitoring tool for heavy metal pollution in the atmosphere
Effects of metal-contaminated soils on the accumulation of heavy metals in different parts of Centella asiatica: a laboratory study
No full textCentella asiatica is widely used as a medicinal plant in Malaysia and other parts of the world. In the present study, the growth and uptake of heavy metal by C. asiatica were determined based on the plant exposure to different treatment of metal-contaminated soils under laboratory conditions. Heavy metals uptake in different parts of the plants namely roots, stems and leaves were determined. In general, it was found that the metal uptake capacity followed the order: roots > stems > leaves. Since a close positive relationship was established between the concentrations of metal accumulated in different parts of the plant and the metal levels in the most contaminated soil, C. asiatica has the potential of being used as a biomonitoring plant for heavy metal pollution in the polluted soils
Distribution of heavy metal concentrations in different soft tissues and shells of the bivalve Psammotaea elongata and Gastropod faunus ater collected from Pantai Sri Tujuh, Kelantan
No full textSnails (Psammotaea elongate) and clams (Faunus ater) collected from Pantai Sri Tujuh, Tumpat (Kelantan) were dissected into operculum, foot, gill, muscle, and digestive caecum. The clams were dissected into siphon, foot, gill, muscle, mantle and remainder parts. The different soft tissues and shells were pooled and determined for Cd, Cu, Pb and Zn. Both species were found to have higher concentrations of non-essential Cd and Pb in their shells than those in the different soft tissues. On the other hand, the soft tissues (especially remainder parts) had consistently higher concentrations of essential Zn and Cu than those in the shells in both molluscs. The ecological distribution and metal concentrations for the two molluscs species found at Pantai Sri Tujuh can serve as a baseline information
Accumulation and depuration of Cu and Zn in the blood cockle Anadara granosa (linnaeus) under laboratory conditions
No full textStudies on the accumulation (4 days of single metal exposure) and depuration (6 days in natural seawater) of Cu and Zn were conducted in the blood cockle Anadara granosa under laboratory conditions. Different rates of accumulation and depuration between the soft and hard tissues probably reflect the different mechanisms of binding and regulation of Cu and Zn between the soft tissues and shells of cockles. At the end of depuration, the concentrations of Cu and Zn in the soft tissues were only 1.71 and 1.75 times higher than prior to the exposure, respectively. Thus, no significant difference was found in the depuration level between Cu and Zn. Hard tissues showed that the levels of Cu and Zn are similar to those before the exposure. This indicated the slow rates of accumulation and depuration in the shells as compared to the soft tissues of A. granosa. The condition index of A. granosa could be used as a potential physiological indicator of metal pollution. The capabilities to accumulate Cu and Zn and to depurate both metals in the soft tissues indicate that A. granosa is a potential biomonitoring organism for its health assessment using the condition index
Distributions of Cu and Zn in the shell lipped part periostracum and soft tissues of perna viridis: the potential of periostracum as a biomonitoring material for Cu contamination
No full textPeriostracum is the outer shell layer composes mainly of organic materials. In the present study, the green-lipped mussel Perna viridis was used to investigate the distributions of Cu and Zn in the periostracum and soft tissues of the P. viridis which were sampled from 17 geographical sites [23 populations] along the coastal waters of Peninsular Malaysia. The concentrations of Cu in the periostracum and the soft tissues of P. viridis were 7.41- 42.63 mg/g dry weight and 3.49-31.1 mg/g dry weight, respectively. Meanwhile, the concentrations of Zn in the periostracum and soft tissues of P. viridis were 4.90-39.79 mg/g dry weight and 65.75-144.9 mg/g dry weight, respectively. The ratios of the metals in periostracum to soft tissues were 0.73-3.99 mg/g for Cu and 0.05-0.36 mg/g for Zn. These ratios indicated that the concentrations of Cu in the periostracum were generally greater than those in the soft tissues while the concentrations of Zn were generally higher in the soft tissues than those in the periostracum. The higher Cu levels in the soft tissues compared to that in the periostracum (Fig. 2) and the relatively close relationships of Cu between periostracum and sediment indicated that the periostracum was a good biomonitoring material for Cu, but periostracum was not a good biomonitoring material for Zn because it did not reflect the environmental contamination as reflected in the low correlation between the periostracum and sediment
Cd and Zn in Nerita lineata collected from selected areas of the south west coast of Peninsular Malaysia
No full text5.60 and 14.26 for opercul
Elevated heavy metal concentrations in surface sediments collected from the drainages of the Sri Serdang industrial area, Malaysia
No full textThe surface sediments were collected from the drainages and rivers of the Sri Serdang Industrial area at six sampling sites in August 2005. The samples were analyzed for total concentrations of Cd, Cu, Pb, Zn and Ni by using the aqua-regia method. The heavy metal concentrations (ug/g dry weight) ranged from 169.3 to 296.3 for Zn, 56.1 to 404.3 for Pb, 2.40 to 10.2 for Cd, 43.0 to 551.2 for Cu and 35.4 to 582.3 for Ni. A sampling site near to a metal manufacturing factory recorded the highest concentrations of Zn, Pb, Cd, Cu and Ni. In addition, these metal ranges were much higher than those reported for other polluted sites in the west coast of Peninsular Malaysia reported by Yap et al. (2002, 2003). Since these metal concentrations were higher than the Interim Sediment Quality Values- high (ISQVs-high) for Hong Kong (Chapman et al., 1999) and Interim Freshwater Sediment Quality Guidelines for Canada (CCME, 2002), these elevated metal concentrations are most likely contributed by nearby industrial activities. Therefore, further ecotoxicological research on heavy metal pollution in the Sri Serdang Industrial area is necessary
Effect of body size on heavy metal contents and concentrations in green-lipped mussel Perna Viridis (linnaeus) from Malaysian coastal waters
No full textThe concentrations of cadmium, copper, zinc and lead, in the total soft tissues of green-lipped mussel Perna viridis of a wide range of sizes (2-11 cm), were determined from a population at Pasir Panjang. The metal contents (?g per individual) and concentrations (?g per g) of cadmium, lead, copper and zinc were studied in P. viridis to find the relationships with body sizes. Smaller and younger mussels showed higher concentrations (?g per g) of Cd, Pb and Zn than the larger and older ones. The results of the present study showed that the plotting of the metal content, against dry body flesh weight on a double logarithmic basis, gave good positive straight line
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