Inventory of heavy metals and organic micropollutants In an urban water catchment drainage basin

The Linggi River drainage basin in Negeri Sembilan Malaysia is the major source of potable water for the townships of Seremban and Port Dickson. Water quality is threatened by industrial and commercial development taking place in the basin. This study investigated the concentrations and distribution of organic micro-pollutants and heavy metals within the catchment. Arsenic, copper, cadmium, lead, mercury and zinc were determined in water and sediment samples. All heavy metal concentrations were increased down the basin; arsenic and copper concentration in particular were elevated probably due respectively to flow in of arsenical herbicides in rubber and oil palm plantations and copper sulphate and an additive in pig food.Total phenol concentration also increased considerably within the catchment as a result of urbanisation. Five priority phenolic pollutants (2,4-dimethylphenol; 4-chloro-3-methylphenol; 2,4,6-trichlorophenol; 4-introphenol; pentachlorophenol) were found.     

The determination of heavy metals in water,suspended materials and sediments from Langat River,Malaysia

The distributions of heavy metals in the Langat River were studied for a period of six months between September 1984 and February 1985. Heavy metals such as arsenic, cadmium, cerium, cobalt, chromium, caesium, lanthanum, rubidium, antimony, scandium, thorium and zinc were determined in water, suspended materials and sediment samples from the Langat River by neutron activation and atomic absorption spectrometry. The concentrations of arsenic, cadmium, cerium, cobalt, scandium, antimony, and zinc were generally highest in the suspended materials, whereas the concentrations of chromium, rubidium and thorium were always highest in the sediments: Arsenic concentrations in the river were slightly higher than the natural concentration, while other elements were generally at their natural concentration levels. The use of arsenical herbicides in plantations along the river could be a source of arsenic pollution.     

Mercury determination in hair of Malaysian fishermen by neutron activation analysis

Biological Trace Element Research - Fish has been known as a source of nonoccupational mercury exposure to fish-consuming population groups. In this study, hair samples collected from fishermen and...     

Nutrient Amendments of Inorganic Fertiliser and Oil Palm Empty Fruit Bunch and Their Influence on Bacterial Species Dominance and Degradation of the Associated Crude Oil Constituents

The effects of inorganic commercial fertiliser (N:P:K = 8:8:1) and oil palm empty fruit bunch (EFB) as nutrient amendments for crude oil degradation and microbial population shift by a microbial consortium [Pseudomonas sp. (UKMP-14T), Acinetobacter sp. (UKMP-12T), Trichoderma sp. (TriUKMP-1M and TriUKMP-2M)] were assessed. The bacterial populations present during crude oil degradation were analysed by spread plate method and 16S rRNA sequences, whereas the presence of fungi was assessed by growth on potato dextrose agar. Crude oil degradation analysed using gas chromatography-flame ionisation detection showed total petroleum hydrocarbon reduced between 70 and 100%, depending on the type of amendments compared to control (≈55%) after 30 days of incubation. Nutrient amendments using NPK fertiliser or EFB were found to influence the domination of different bacterial species, which in turn preferentially utilised different hydrocarbons. This study suggested different nutrient amendments could be used to preferentially select bacteria to degrade different components of crude oil, particularly pertaining to the recalcitrant phytane. This information is very useful for application of in situ bioremediation of soil hydrocarbon contamination.     

Relationship between root colonization and initial adsorption ofAzospirillum to plant roots

Four strains ofAzospirillum were ranked according to numbers of cells adsorbed on the roots of seedlings in liquid medium, and the rankings were evaluated for their usefulness in predicting success of colonization of the roots of pot-grown plants. Different rankings were observed on different parts of the roots and on different host plants. Rhizosphere colonization results for rice were similar to those for clover and showed little difference between bacterial strains. The population densities were approximately equal to those of the most dense strains in the wheat rhizosphere, whereas the highest concentrations in the root interior of clover and rice were only about one-tenth of those in wheat. Rankings of initial adsorptive ability on various parts of the roots showed potential for predicting the best strains for colonizing the root interiors of wheat and clover. On wheat, the two strains (Cd and SpBr14) which showed best initial adsorption to the root cap were best at colonizing the endorhizosphere of pot-grown plants. For rice, strains Cd and SpBr14 gave lowest and highest values, respectively, both for adsorption to the terminal 2 cm of roots and for subsequent colonization of the root interior. Data on initial adsorption were of no value in predicting the relative success of strains in colonizing the root surface of any host plants or the interior of clover roots.     

Elemental analysis of herbal preparations for traditional medicines by neutron activation analysis with the k0 standardization method

Medicinal herb preparations prescribed for specific treatment purposes were purchased from markets and were analyzed by instrumental neutron activation analysis withk ₀ standardization. Then, 500–700 mg of each sample was pelletized under a pressure of six tones and irradiated together with monitors for a and neutron flux ratio determinations for about 6 h in a thermal flux of 2.29 x 10¹² n/cm²/s. The accuracy of the method was established by analyzing standard reference materials. Twenty-nine elements, Ag, As, Au, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Mn, Mo, Na, Rb, Sb, Sc, Se, Sm, Sr, Th, U, Yb, and Zn, were measured in all the samples, and Hg was detected in some samples, with good accuracy and reproducibility. The concentration of elements determined was found to vary depending on the composition of the herbs used. Although the trend linking the element of the medicinal plants to its curative abilities could not be clearly determined, this study showed that the toxic elements found in the samples were below the levels prescribed by health regulations. Nevertheless, such data are important to understand the pharmacological action and the exact mechanisms of action and formation of active constituents for each medicinal plant and to decide the dosage of the herbs used in the final formulation.     

Distribution of cyclic imide-transforming activity in microorganisms

Cyclic imide-transforming activity was found to be widely distributed in bacteria, yeast and molds. This activity was not correlated with cyclic ureide-transforming activity in bacteria, but there was some correlation in yeast and molds. These two activities are probably catalyzed by different enzymes in bacteria. Besides the well-known cyclic ureide transformation, cyclic imide transformation by microorganisms was common.     

Instrumental neutron activation analysis of kidney stones

Biological Trace Element Research - Kidney stone samples of the types calcium oxalate, uric acid, and xanthine were analyzed for their elemental contents by neutron activation analysis to study...