Multi-residue analytical method for human pharmaceuticals and synthetic hormones in river water and sewage effluents by solid-phase extraction and liquid chromatography–tandem mass spectrometry.

Pollutants such as human pharmaceuticals and synthetic hormones that are not covered by environmental legislation have increasingly become important emerging aquatic contaminants. This paper reports the development of a sensitive and selective multi-residue method for simultaneous determination and quantification of 23 pharmaceuticals and synthetic hormones from different therapeutic classes in water samples. Target pharmaceuticals include anti-diabetic, antihypertensive, hypolipidemic agents, β2-adrenergic receptor agonist, antihistamine, analgesic and sex hormones. The developed method is based on solid phase extraction (SPE) followed by instrumental analysis using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC–ESI-MS/MS) with 30 min total run time. River water samples (150 mL) and (sewage treatment plant) STP effluents (100 mL) adjusted to pH 2, were loaded into MCX (3 cm3, 60 mg) cartridge and eluted with four different reagents for maximum recovery. Quantification was achieved by using eight isotopically labeled internal standards (I.S.) that effectively correct for losses during sample preparation and matrix effects during LC–ESI-MS/MS analysis. Good recoveries higher than 70% were obtained for most of target analytes in all matrices. Method detection limit (MDL) ranged from 0.2 to 281 ng/L. The developed method was applied to determine the levels of target analytes in various samples, including river water and STP effluents. Among the tested emerging pollutants, chlorothiazide was found at the highest level, with concentrations reaching up to 865 ng/L in STP effluent, and 182 ng/L in river water

Genetic structure of glyphosate-resistant ( R ) and glyphosate-susceptible ( S ) populations of Eleusine indica (L.) Gaertn from Peninsular Malaysia

Glyphosate is the world’s most widely used herbicide, accounting for 11 % of worldwide herbicide sales (Powles et al., 1997). As a nonselective herbicide with no soil activity (Grossbard & Atkinson 1985), it is an ideal herbicide to control a broad range of weed species. In Malaysia, glyphosate is used to control various weed species growing in oil palm and rubber plantations. In some instances, multiple treatments have been carried out continuously for several years

Content determination and health risk assessment of polycyclic aromatic hydrocarbon in fish tissue samples from Perhentian Island, Malaysia

The concentration of polycyclic aromatic hydrocarbon (PAH) in three fish species with different feeding habits and habitat i.e. Lolong (Selar boops), Kerisi (Nemipterus peronii) dan Mengkarong (Trachinocephalus myops) from offshore of Perhentian Island, Malaysia was determined. Three individuals from each species were taken at random and the PAHs contents were determined in the muscles. Ten PAH compounds, phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(e)pyrene and dibenzo(a,h)anthracene were determined. PAH in fish tissues was extracted using Soxhlet method and detected using gas chromatography – mass spectrometry (GC-MS). The level of PAH in fish tissue ranged from 17.89 – 42.18 ng/g wet weight and 393.98 – 511.07 ng/g lipid weight. The order of PAH concentration in wet weight was Kerisi (511.07 ng/g)> Mengkarong (409.50 ng/g)> Lolong (393.98 ng/g) but in terms of lipid weight, the order was Kerisi (511.07 ng/g)> Mengkarong (409.50 ng/g)> Lolong (393.98 ng/g). Kerisi has the lowest lipid content of 3.5% compared to Lolong (6.5 %) and Mengkarong (10.3 %). No obvious significant difference (p>0.05) of PAH levels in three fish spesies was observed (ANOVA, p>0.05). There was no significant relationship between lipid content and PAH accumulation in fish. Based on fish consumption rate of 142.2 g/day, the Potency Equivalent Concentration (PEC), which is a carcinogenic potency value for PAH, was found to be ranged from 0.41 – 0.63 ng/g wet weight in all three species of fish. This value is below the limit set by USEPA, which is 0.67 ng/g wet weight for human consumption

Flood analysis of December 2006: focus at Segamat Town, Johor

This study aimed to ascertain the causes of Segamat flood which occurred from 17 to 21 December 2006. Actvities include collection, evaluation and analysis of rainfall data from January 1998 to December 2006, and analysis of daily telemetry for water levels and discharge in December 2006. The daily, monthly and annual rainfall of Felda Medoi Station, Segamat were analyzed and correlated with the telemetry data. Based on the 9 years rainfall data, monthly rainfall in Segamat area ranged from 2.5 mm (Februari 2004) to 536.8 mm (January 2003). Monthly rainfall distribution from October to December 2006 increased from 118 mm to 435 mm but decreased (392 mm) in January 2007. Our result showed that extra ordinary heavy downpour, low and undulating topography of the study area was identified as the main cause for the Segamat flood. Keywords: 2006 Segamat flood; Felda Medoi station; stream flow; telemetry dat

Spatial distribution and sources of polycyclic aromatic hydrocarbons (PAHs) in green mussels (Perna viridis) from coastal areas of Peninsular Malaysia: implications for source identification of perylene

Distribution of polycyclic aromatic hydrocarbons (PAHs) was determined in green mussels (Perna viridis) from various sites in coastal waters of Peninsular Malaysia between August 2004 and January 2007, in order to assess contamination by petroleum hydrocarbons. The range of ∑PAHs detected in mussels was from 766 to 110500 (ng/g lipid wt.). High concentrations of PAHs were found in mussel tissues collected near Penang Bridge. The ratios of methyl phenanthrenes to phenanthrene (∑MP/P ratio) for Penang, Kg. Pasir Puteh and Tebing Runtuh (Johore Straits) were greater than 2, indicating extensive input of petrogenic PAHs. The results indicated that male individuals elevated more considerable concentrations of PAHs in their soft tissues in comparison to female individuals. The results of independent sample T-test showed that there were no significant differences (p > 0.05) between male and female mussels analysed in the Pasir Panjang station. Negative significant correlations (r = −0.890, p < 0.01) and (r = −0.0655, p < 0.05), were found between weight and total of PAHs in female and male species, respectively. This indicated that body weight of each individual was not affected by the PAHs concentrations. The present study proposes the use of soft tissue of Perna viridis as a biomonitor of perylene bioavailability and contamination in coastal waters of Peninsular Malaysia

Use of different tissues of Perna viridis as biomonitors of polycyclic aromatic hydrocarbons (PAHs) in the coastal waters of Peninsular Malaysia

For the first time, in May 2007, the distributions of polycyclic aromatic hydrocarbons (PAHs) were studied in the soft tissues (STs) (mantle, gills, foot, gonad, muscle, byssus, and remaining soft tissues) of the green-lipped mussel Perna viridis, collected from eight geographic locations along the coastal waters of peninsular Malaysia. The STs of the mussels collected from the eastern part of the Johore Straits indicated higher bioavailability of and contamination by PAHs than from other areas. The results also indicated a significantly higher concentration of the lower molecular weight (LMW) PAHs in tissues compared to that of the higher molecular weight (HMW) PAHs, perhaps due to the greater bioavailability of the more water-soluble LMW PAHs or related to a partial biotransformation of the higher molecular weight PAHs. The results also suggest that the differences found in the contents of PAHs in various STs of P. viridis were mainly due to differences between individual PAHs volatility and solubility in water, as well as the mechanism of PAH accumulation by mussels. Of the STs in general, the gonad was shown to contain the highest levels of PAHs, but it is not a potential biomonitoring organ because it is highly influenced by spawning conditions. Isomeric PAH ratios were used to differentiate pollution sources.The findings of the study suggest that STs of P. viridis are good biomonitors of the bioavailability and contamination with PAHs in tropical coastal waters