Endocrine disrupting compounds (EDCs) in environmental matrices: review of analytical strategies for pharmaceuticals, estrogenic hormones, and alkylphenol compounds

Endocrine disrupting compounds (EDCs) have been widely reported as potential carcinogenic threats to the human population. The release of EDCs to environmental compartments, such as water, sediment, and biota, has been monitored extensively. Considering the typically low levels of EDC concentrations found in environmental samples and the complexity of biota matrices, the main challenge is with the extraction and cleanup of samples, as well as with finding a sensitive enough instrumentation system for analyte detection. This paper presents a review of recent trends in the analysis of EDCs in environmental matrices. The focus of this review is three classes of environmentally important EDCs; namely, pharmaceuticals, estrogenic hormones, and alkylphenol compounds. Discussions about state-of-the-art instrumentation and sample preparation techniques, as well as a review of sample storage and preservation, are highlighted. Overall, the use of LC-MS-MS as an instrumentation technique has increased over the past 15 years

Occurrence and level of emerging organic contaminant in fish and mollusk from Klang River estuary, Malaysia and assessment on human health risk

The occurrence, level, and distribution of multiclass emerging organic contaminants (EOCs) in fish and mollusks from the Klang River estuary were examined. The targeted EOCs for this assessment were phenolic endocrine disrupting compounds (bisphenol A, 4-OP, and 4-NP), organophosphorous pesticides (quinalphos, chlorpyrifos, and diazinon), estrogenic hormones (E2, E1, and EE2), and pharmaceutically active chemicals (primidone, sulfamethoxazole, dexamethasone, diclofenac, amoxicillin, progesterone, and testosterone). Results from this study showed that the prevalent contamination of the Klang River estuary by EOCs with diclofenac, bisphenol A, progesterone, and amoxicillin were predominantly detected in fish and mollusks. Among the EOCs, diclofenac and progesterone had the highest concentrations in fish and mollusk samples, respectively. The concentrations of diclofenac and progesterone in fish and mollusk samples range from 1.42 ng/g to 10.76 ng/g and from 0.73 ng/g to 9.57 ng/g, respectively. Bisphenol A should also be highlighted because of its significant presence in both fish and mollusks. The concentration of bisphenol A in both matrices range from 0.92 ng/g to 5.79 ng/g. The calculated hazard quotient (HQ) for diclofenac, bisphenol A, and progesterone without consideration to their degradation byproduct were less than one, thus suggesting that the consumption of fish and mollusks from the Klang River estuary will unlikely pose any health risk to consumers on the basis of the current assessment. Nonetheless, this preliminary result is an important finding for pollution studies in Malaysian tropical coastal ecosystems, particularly for organic micropollutant EOCs, and can serve as a baseline database for future reference

Mineralogy and geochemistry of gold mineralization at Southern Part of Ulu Sokor Gold Deposit, Kelantan, Malaysia

The Ulu Sokor gold deposit is classified as orogenic type deposit with evidence from previous studies on the structural, mineralogical, alteration, fluid inclusion, and stable isotope data. This study focuses on the mineralogy and geochemical analysis of representative ore rock samples from southern part of Ulu Sokor gold deposits. The project area is situated at the North of Kelantan state which lies on the Central Belt of Peninsular Malaysia. The main objective of this research is to determine the gold mineralization enrichment pattern relative to other trace elements based on the new data of mineralogy and geochemical analysis. Gold mineralization is primarily hosted in structurally controlled quartz vein which occurs in various degrees of ductile-brittle environment. Based on the field relationships, ore microscopy and geochemical data analysis, there are two main gold mineralization type in the southern part of Ulu Sokor gold deposit, namely (1) Gold associated and as inclusions in bismuthinite based on the mineralogy study, and (2) Refractory gold occurs as lattice bound in pyrite based on the Au/As molar ratio. In terms of mineral exploration and gold prospecting, the significant enrichment in this study area is Bi. However, some other metals can also be considered as a significant value in this area such as Pb, As, Cu and Zn. From the bulk ore chemistry, the geometric mean values of Au and Bi are 1.9 ppm Au (n=23) and 96 ppm Bi (n=22), respectively. The knowledge base for bismuth minerals in Malaysia would provide a significant targeting clue for the gold mineralization

Risk assessment of pharmaceutically active compounds (PhACs) in the Klang River estuary, Malaysia

The concentration profile, distribution and risk assessment of pharmaceutically active compounds (PhACs) in the coastal surface water from the Klang River estuary were measured. Surface coastal water samples were extracted using offline solid phase, applying polymeric C18 cartridges as extraction sorbent and measuring with liquid chromatography mass spectrometry-mass spectrometry (LC MS-MS) technique. Extraction method was optimized for its recovery, sensitivity and linearity. Excellent recoveries were obtained from the optimized method with percentage of recoveries ranging from 73 to 126%. The optimized analytical method achieved good sensitivity with limit of detection ranging from 0.05 to 0.15 ng L-1, while linearity of targeted compounds in the LC MS-MS system was more than 0.990. The results showed that amoxicillin has the highest concentration (102.31 ng L-1) followed by diclofenac (10.80 ng L-1) and primidone (7.74 ng L-1). The percentage of contribution (% of total concentration) for the targeted PhACs is in the following order; amoxicillin (92.90%) > diclofenac (3.95%) > primidone (1.23%) > dexamethasone (0.75%) > testosterone (0.70%) > sulfamethoxazole (0.33%) > progesterone (0.14%). Environmental risk assessment calculated based on deterministic approach (the RQ method), showed no present risk from the presence of PhACs in the coastal water of Klang River estuary. Nonetheless, this baseline assessment can be used for better understanding on PhACs pollution profile and distribution in the tropical coastal and estuarine ecosystem as well as for future comparative studies

Multiclass analysis of emerging organic contaminants in tropical marine biota using improved QuEChERS extraction followed by LC MS/MS

Marine biota is one of the important components of an ecosystem, and it has been widely used as a pollution indicator for emerging organic contaminants (EOCs) in the coastal zone. Previous studies divulged the concentration of EOCs in various types of biota matrices at trace level detection. EOCs have been associated with several adverse human health effects. Bioaccumulation of EOCs in the food web has been the main concern, and thus a sensitive and selective method for trace quantification of EOCs in biota matrices need to be developed and optimized. Considering various matrix interferences for EOC analysis in marine biota, a combination technique of QuEChERS and solid phase extraction cleanup with detection based on liquid chromatography with tandem mass spectrometry (LC MS/MS) is presented in this study. A method for 16 compounds grouped into four different classes, namely, pharmaceutically active chemicals, phenolic endocrine disrupter compounds, estrogenic hormones, and pesticides, was developed and validated for biota extraction. Satisfactory extraction was obtained for the optimized method with percentage of recovery from 64% to 114% and excellent sensitivity with detection limit in the range of 0.02–3.50 ng/g. Linearity of the standards (in the solvent) in the LC MS-MS analysis ranged from 0.991 to 0.999. The relative standard deviation for intra-day and inter-day repeatability was less than 20%, indicating good-precision analysis. Assessment on the matrix effects showed ionization suppression for all the developed compounds. The developed method was verified by analyzing biota matrices collected from the Klang River estuary. Trace concentrations of EOCs, ranging from 0.05 to 10.76 ng/g, were found in those matrices. Of the 16 targeted compounds, 10 were detected, namely, diclofenac, bisphenol A, sulfamethoxazole, amoxicillin, E2, E1, progesterone, testosterone, primidone, and 4-octylphenol. The other compounds were below the method detection limit

Investigation of nitrogen doped graphene as saturable absorber in Thulium-Doped Fiber Laser

The work investigated the Q-switched Thulium-Doped Fiber Laser (TDFL) that operates in 1900 nm region by using nitrogen graphene (NG) embedded in polyethylene oxide (PEO) as saturable absorber (SA). The highest output power achieved was 0.52 mW with highest repetition rate of 33.43 kHz. The shortest pulse width was 3.205 µs with pulse energy of 31.11 nJ

Deposition of silver nanoparticles on polyvinyl alcohol film using electron beam evaporation and its application as a passive saturable absorber

This study investigated the generation of Q-switched pulse in fibre laser operation at 1550 nm wavelength region using silver nanoparticles (Ag NPs) as passive saturable absorber (SA). The Ag NP SA was prepared through the electron beam evaporation method with a thickness of 10 nm on pure polyvinyl alcohol (PVA) film. The average size of the Ag NPs was around 50 nm and the existence of silver element had been investigated by using the energy dispersive spectroscopy (EDS) technique. The modulation depth of the developed silver-based passive SA was 19% with saturation intensity of 170.26 mW/cm 2 . The laser was operated at 1560 nm centre wavelength with 3 dB spectral bandwidth of 1.3 nm. The pulsed laser was able to generate pulse energy of 146.4 nJ with peak power of 20.5 mW at a maximum pump of 90.4 mW. A signal-to-noise ratio (SNR) value of 67.5 dB was obtained at the repetition rate of 65.4 kHz for maximum input pump power