Microplastic extraction from digestive tracts of large decapods.

The reliable quantification of microplastic contamination in chitinous organisms requires validated methods to remove interfering complex organic and inorganic material. This study trialled KOH, HO and HNO digestion methods on the digestive tracts of two large decapods (Panulirus cygnus and Portunus armatus) to validate a protocol that facilitates reliable microplastic extraction. KOH digestion provided the best recovery (>95 %) of all polymers (e.

Use of micropollutant indicator ratios to characterize wastewater treatment plant efficiency and to identify wastewater impact on groundwater.

Contamination by wastewater has been traditionally assessed by measuring faecal coliforms, such as E. coli and entereococci. However, using micropollutants to track wastewater input is gaining interest.

Comparison of Approaches for Authentication of Commercial Terpinen-4-ol-type Tea Tree Oils Using Chiral GC/MS.

A global demand for tea tree oil (TTO) has resulted in increased adulteration in commercial products. In this study, we use a novel enantiomeric gas chromatography mass spectrometry method for chiral analysis of key terpenes ((±)-terpinen-4-ol, (±)-α-terpineol, and (±)-limonene) and quantification of components present at >0.01% to test different methods of identifying adulterated TTO.

Development and validation of a direct injection liquid chromatography-tandem mass spectrometry method for the analysis of illicit drugs and psychopharmaceuticals in wastewater.

A direct injection liquid chromatography-tandem mass spectrometry method was successfully developed for the analysis of 19 illicit drugs and psychopharmaceuticals in raw and treated wastewater. The method includes the analysis of stimulants and opioids, and antidepressant, antipsychotic, antianxiety, appetite suppressant and hallucinogen drugs. The method limits of quantification range from 5 - 59 ng L and 2 - 38 ng L in raw and treated wastewater, respectively.

Halogenated semivolatile acetonitriles as chloramination disinfection by-products in water treatment: a new formation pathway from activated aromatic compounds.

The use of monochloramine as an alternative disinfectant to chlorine in drinking water treatment can lead to increased formation of emerging nitrogenous halogenated disinfection by-products (DBPs), even when the formation of regulated halogenated DBPs has decreased. In this study, we investigated formation of the semivolatile haloacetonitriles (HANs) from model nitrogen-containing compounds (6 amines, 1 amide, 6 amino acids, and 2 nitrogen-containing aromatic chemicals) and natural organic matter (NOM) reference materials after chloramination. In agreement with previous studies, most amino acids formed dichloroacetonitrile (DCAN).

Identification of eukaryotic microorganisms with 18S rRNA next-generation sequencing in wastewater treatment plants, with a more targeted NGS approach required for Cryptosporidium detection.

While some microbial eukaryotes can improve effluent quality in wastewater treatment plants (WWTPs), eukaryotic waterborne pathogens are a threat to public health. This study aimed to identify Eukarya, particularly faecal pathogens including Cryptosporidium, in different treatment stages (influent, intermediate and effluent) from four WWTPs in Western Australia (WA). Three WWTPs that utilise stabilisation ponds and one WWTP that uses activated sludge (oxidation ditch) treatment technologies were sampled.

Evaluation of 16S next-generation sequencing of hypervariable region 4 in wastewater samples: An unsuitable approach for bacterial enteric pathogen identification.

Recycled wastewater can carry human-infectious microbial pathogens and therefore wastewater treatment strategies must effectively eliminate pathogens before recycled wastewater is used to supplement drinking and agricultural water supplies. This study characterised the bacterial composition of four wastewater treatment plants (WWTPs) (three waste stabilisation ponds and one oxidation ditch WWTP using activated sludge treatment) in Western Australia. The hypervariable region 4 (V4) of the bacterial 16S rRNA (16S) gene was sequenced using next-generation sequencing (NGS) on the Illumina MiSeq platform.

Formation of odorous and hazardous by-products from the chlorination of amino acids.

The formation of odorous aldehydes and N-chloraldimines, and also nitriles, which are potentially hazardous to human health, was investigated in studies of the chlorination of amino acids (AAs) in both operational drinking water treatment plants and laboratory-based experiments. In the drinking water treatment plants studied, the concentration of total free AAs did not significantly change after treatment, even though good removal of DOC was observed. However, free AAs still contributed less than 3% of total nitrogen in the treated drinking waters, and no aldehydes, N-chloraldimines or nitriles of interest were detected in the treated waters, presumably due to the low concentrations of the precursor AAs in these water samples.

Removal of organic micropollutants in waste stabilisation ponds: A review.

As climate change and water scarcity continue to be of concern, reuse of treated wastewater is an important water management strategy in many parts of the world, particularly in developing countries and remote communities. Many countries, especially in remote regional areas, use waste stabilisation ponds (WSPs) to treat domestic wastewater for a variety of end uses, including using the treated wastewater for irrigation of public spaces (e.g.

Organic chloramines in chlorine-based disinfected water systems: A critical review.

This paper is a critical review of current knowledge of organic chloramines in water systems, including their formation, stability, toxicity, analytical methods for detection, and their impact on drinking water treatment and quality. The term organic chloramines may refer to any halogenated organic compounds measured as part of combined chlorine (the difference between the measured free and total chlorine concentrations), and may include N-chloramines, N-chloramino acids, N-chloraldimines and N-chloramides. Organic chloramines can form when dissolved organic nitrogen or dissolved organic carbon react with either free chlorine or inorganic chloramines.

Formation and control of nitrogenous DBPs from Western Australian source waters: Investigating the impacts of high nitrogen and bromide concentrations.

We studied the formation of four nitrogenous DBPs (N-DBPs) classes (haloacetonitriles, halonitromethanes, haloacetamides, and N-nitrosamines), as well as trihalomethanes and total organic halogen (TOX), after chlorination or chloramination of source waters. We also evaluated the relative and additive toxicity of N-DBPs and water treatment options for minimisation of N-DBPs. The formation of halonitromethanes, haloacetamides, and N-nitrosamines was higher after chloramination and positively correlated with dissolved organic nitrogen or total nitrogen.

Chlorination of Amino Acids: Reaction Pathways and Reaction Rates.

Chlorination of amino acids can result in the formation of organic monochloramines or organic dichloramines, depending on the chlorine to amino acid ratio (Cl:AA). After formation, organic chloramines degrade into aldehydes, nitriles and N-chloraldimines. In this paper, the formation of organic chloramines from chlorination of lysine, tyrosine and valine were investigated.

Formation of nitrogenous disinfection by-products in 10 chlorinated and chloraminated drinking water supply systems.

The presence of nitrogenous disinfection by-products (N-DBPs) in drinking water supplies is a public health concern, particularly since some N-DBPs have been reported to be more toxic than the regulated trihalomethanes and haloacetic acids. In this paper, a comprehensive evaluation of the presence of N-DBPs in 10 drinking water supply systems in Western Australia is presented. A suite of 28 N-DBPs, including N-nitrosamines, haloacetonitriles (HANs), haloacetamides (HAAms) and halonitromethanes (HNMs), were measured and evaluated for relationships with bulk parameters in the waters before disinfection.

Organic chloramines in drinking water: An assessment of formation, stability, reactivity and risk.

Although organic chloramines are known to form during the disinfection of drinking water with chlorine, little information is currently available on their occurrence or toxicity. In a recent in vitro study, some organic chloramines (e.g.

Degradation rates of benzotriazoles and benzothiazoles under UV-C irradiation and the advanced oxidation process UV/H2O2.

Benzotriazoles (BTs) and benzothiazoles (BTHs) are extensively used chemicals found in a wide range of household and industrial products. They are chemically stable and are therefore ubiquitous in the aquatic environment. The present study focuses on the potential of ultraviolet (UV) irradiation, alone or in combination with hydrogen peroxide (H2O2), to remove BTs and BTHs from contaminated waters.

Analysis of free amino acids in natural waters by liquid chromatography-tandem mass spectrometry.

This paper reports a new analytical method for the analysis of 18 amino acids in natural waters using solid-phase extraction (SPE) followed by liquid chromatography-electrospray tandem mass spectrometry (LC-MS/MS) operated in multiple reaction monitoring mode. Two different preconcentration methods, solid-phase extraction and concentration under reduced pressure, were tested in development of this method. Although concentration under reduced pressure provided better recoveries and method limits of detection for amino acids in ultrapure water, SPE was a more suitable extraction method for real samples due to the lower matrix effects for this method.

Development of a solid-phase extraction liquid chromatography tandem mass spectrometry method for benzotriazoles and benzothiazoles in wastewater and recycled water.

Two methods employing solid-phase extraction and liquid chromatography tandem mass spectrometry were developed for the analysis of benzotriazoles (BTs) and benzothiazoles (BThs), compounds which are commonly found in a large variety of commercial and household products. The first method was able to detect 7 BTs and 7 BThs, the largest suite of BTs and BThs analysed in a single method to-date, but could not distinguish between the isomers, 4-methylbenzotriazole (4-MeBT) and 5-methylbenzotriazole (5-MeBT). Therefore, a second method was developed to achieve the chromatographic separation of 4-MeBT and 5-MeBT.

Determination of halonitromethanes and haloacetamides: an evaluation of sample preservation and analyte stability in drinking water.

Simultaneous quantitation of 6 halonitromethanes (HNMs) and 5 haloacetamides (HAAms) was achieved with a simplified liquid-liquid extraction (LLE) method, followed by gas chromatography-mass spectrometry. Stability tests showed that brominated tri-HNMs immediately degraded in the presence of ascorbic acid, sodium sulphite and sodium borohydride, and also reduced in samples treated with ammonium chloride, or with no preservation. Both ammonium chloride and ascorbic acid were suitable for the preservation of HAAms.

Recycled water: potential health risks from volatile organic compounds and use of 1,4-dichlorobenzene as treatment performance indicator.

Characterisation of the concentrations and potential health risks of chemicals in recycled water is important if this source of water is to be safely used to supplement drinking water sources. This research was conducted to: (i) determine the concentration of volatile organic compounds (VOCs) in secondary treated effluent (STE) and, post-reverse osmosis (RO) treatment and to; (ii) assess the health risk associated with VOCs for indirect potable reuse (IPR). Samples were examined pre and post-RO in one full-scale and one pilot plant in Perth, Western Australia.

Occurrence of iodinated X-ray contrast media in indirect potable reuse systems.

A lack of knowledge of the health and environmental risks associated with chemicals of concern (COCs) and also of their removal by advanced treatment processes, such as micro-filtration (MF) and reverse osmosis (RO), have been major barriers preventing establishment of large water recycling schemes. As part of a larger project monitoring over 300 COCs, iodinated X-ray contrast media compounds (ICM) were analysed in treated secondary wastewater intended for drinking purposes. ICM are the most widely administered intravascular pharmaceuticals and are known to persist in the aquatic environment.

Bioavailability of nanoscale metal oxides TiO(2), CeO(2), and ZnO to fish.

Nanoparticles (NPs) are reported to be a potential environmental health hazard. For organisms living in the aquatic environment, there is uncertainty on exposure because of a lack of understanding and data regarding the fate, behavior, and bioavailability of the nanomaterials in the water column. This paper reports on a series of integrative biological and physicochemical studies on the uptake of unmodified commercial nanoscale metal oxides, zinc oxide (ZnO), cerium dioxide (CeO(2)), and titanium dioxide (TiO(2)), from the water and diet to determine their potential ecotoxicological impacts on fish as a function of concentration.

Analysis of pharmaceuticals in indirect potable reuse systems using solid-phase extraction and liquid chromatography-tandem mass spectrometry.

A solid-phase extraction (SPE) LC-MS/MS method for 18 commercial drugs in secondary wastewater and product water from water recycling plants using microfiltration (MF) and reverse osmosis (RO) has been developed, optimised and validated. The method incorporates a range of multi-class pharmaceuticals including lipid lowering agents, analgesics, antipyretics, non-steroidal anti-inflammatory drugs, antidepressants, anticoagulants, tranquilizers, cytostatic agents, and antiepileptics. Method limits of quantitation (MLQs) in secondary wastewater ranged from 15 to 250 ng/L, while MLQs in post-RO water ranged from 1 to 25 ng/L.

Dioxins, furans and PCBs in recycled water for indirect potable reuse.

An assessment of potential health impacts of dioxin and dioxin-like compounds in recycled water for indirect potable reuse was conducted. Toxic equivalency factors (TEFs) for 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (PCBs) congeners have been developed by the World Health Organization to simplify the risk assessment of complex mixtures. Samples of secondary treated wastewater in Perth, Australia were examined pre-and post-tertiary treatment in one full-scale and one pilot water reclamation plant.

Rapid analysis of iodinated X-ray contrast media in secondary and tertiary treated wastewater by direct injection liquid chromatography-tandem mass spectrometry.

The iodinated X-ray contrast media are the most widely administered intravascular pharmaceuticals and are known to persist in the aquatic environment. A rapid method using direct injection liquid chromatography-tandem mass spectrometry (DI-LC-MS/MS) has been developed to measure eight ICM. These include iopamidol, iothalamic acid, diatrizoic acid, iohexol, iomeprol, iopromide, plus both ioxaglic acid and iodipamide, which have not previously reported in the literature.

The Pb pollution fingerprint at Lochnagar: the historical record and current status of Pb isotopes.

Ratios of 206Pb/207Pb in a Lochnagar sediment core slowly decline from c. 1.32 at 140 cm to c.