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This study assessed the impact of heat treatment on beta-casomorphin 5 (β-CM5) and beta-casomorphin 7 (β-CM7) after in-vitro gastrointestinal digestion of milk representing beta-casein (β-CN) A1A1, A2A2 and A2I phenotype. After heat treatment at 73 °C/20 s, 85 °C/5 min and 121 °C/12 min, milk samples were subjected to in-vitro gastrointestinal digestion. β-CM5/7 were analysed using ultra high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and further confirmed using ultra high-performance liquid chromatography-high resolution accurate mass Orbitrap™ mass spectrometry (UHPL-HRMS). β-CM5 was not released after in-vitro gastrointestinal digestion of all heated milk. Similarly, β-CM7 was not released in all milk with β-CN A2A2 phenotype. However, this peptide level ranged from 127.25 to 198.10 ng/mL (4.94–7.70 ng/mg protein) in heated milk with β-CN A1A1 phenotype, whereas it was released at much lower levels ranging from 19.35 to 24.50 ng/mL (0.71–0.91 ng/mg protein) in heated milk with β-CN A2I phenotype.

While nutrient removal has been well studied in waste stabilisation ponds (WSPs), studies of organic micropollutant removal in pond systems are limited. In this study, we investigated organic micropollutant, nitrogen and organic carbon removal in selected WSPs that differed in geographical location and pond configuration, and compared their performance to an oxidation ditch wastewater treatment plant (WWTP). Of the 232 chemicals measured, 36 were detected in wastewater influent and 33 were detected in treated wastewater effluent. New data for micropollutant removal in WSPs was generated for three pesticides or related chemicals, five pharmaceuticals, the plasticizer N-butylbenzenesulfonamide, the antioxidant 2,6-di-t-butyl-p-cresol, and two flame retardants tris(dichloropropyl)phosphate and tris(chloropropyl)phosphate isomers. Most of these micropollutants were relatively well removed in WSPs. The poorest treatment efficiency was observed in the single facultative pond system, with no maturation pond, suggesting that the presence of a maturation pond is important for chemical removal. The two WSPs in temperate climates were found to have higher concentrations of motile algae that can optimise their position with respect to light and temperature. However, to-date, the micropollutant removal by these algal species is not known. The highest removals of micropollutants in a WSP were measured in a complex WSP system with two maturation ponds, and the removals achieved were comparable to the oxidation ditch system. The key factors contributing to high micropollutant removal in this WSP were high solar irradiation and warm temperatures that promoted the growth of non-motile green algae previously found to degrade micropollutants, and photodegradation.

The objective of this study was to determine the β-CN phenotypes in cow milk collected from HF and cross-bred HF dairy cattle in Phu Dong, Vietnam. In total, 85 samples of raw milk were collected from 85 individual cows. Beta-casein (β-CN) phenotypes in cow milk were determined using ultra-high performance liquid chromatography coupled to high resolution mass spectrometry (UHPLC-HRMS). The results showed that three β-CN variants A1, A2 and I were detected and identified in the milk samples. Five β-CN phenotypes A1A1, A1A2, A1I, A2A2 and A2I were found with percentages of 0.035, 0.400, 0.059, 0.482 and 0.024, respectively. The higher proportion of β-CN phenotype A2A2 compared to other phenotypes was expected because of changes in dairy cow breeding in Phu Dong, Vietnam.

The authors regret that the printed version of the above article contained errors in the colour codes of Fig. 3, Fig. 4. The correct figures should have shown the ‘Perth Hills’ site in red and the ‘Matuwa’ site in black as per Fig. 2. The correct and final versions of Fig. 3, Fig. 4 are shown below. The authors would like to apologise for any inconvenience caused.

Anticoagulant rodenticides (ARs) are regularly used around the world to control pest mammals. Second-generation anticoagulant rodenticides (SGARs) are highly persistent in biological tissue and have a high potential for bioaccumulation and biomagnification. Consequently, exposure and poisoning of non-target organisms has been frequently documented, especially in countries with unregulated AR sales and usage. Most of this research has focussed on rodent-predators, usually raptors and predatory mammals, although exposure has also been documented in invertebrates and insectivorous fauna. Few studies have explored non-target exposure in reptiles, despite species sharing similar trophic positions and dietary preferences to other exposed fauna. We tested three abundant urban reptile species in Perth, Western Australia that differ in diet and trophic tiers for multiple AR exposure, the dugite Pseudonaja affinis (rodent-predator), the bobtail Tiliqua rugosa (omnivore) and the tiger snake Notechis scutatus occidentalis (frog-predator). We found frequent exposure in all three species (91% in dugites, 60% in bobtails and 45% in tiger snakes). Mean combined liver concentrations of ARs of exposed individuals were 0.178 mg/kg in dugites, 0.040 mg/kg in bobtails and 0.009 mg/kg in tiger snakes. High exposure frequency and liver concentration was expected for the dugite. Exposure in the other species is more surprising and implies widespread AR contamination of the food web. We discuss the likelihood of global AR exposure of urban reptiles, highlight the potential for reptiles to be important vectors of ARs in the food web and highlight implications for humans consuming wild reptiles.

Beta-casomorphin peptides including beta-casomorphin 5 (β-CM5) and beta-casomorphin 7 (β-CM7) in raw cow milk were analyzed using a liquid chromatography-tandem mass spectrometry (LC-MS/MS). Milk samples were acidified with HCl followed by centrifuged and cleaned-up using solid-phase extraction (SPE). The eluents were evaporated to dryness and subsequently reconstituted with methanol. Limits of detection (LOD) were 0.32 ng/g for β-CM5 and 0.24 ng/g for β-CM7 and limits of quantification (LOQ) were 1.06 ng/g and 0.69 ng/g for β-CM5 and β-CM7, respectively. Recoveries ranged from 89.7% to 99.4% for β-CM5 and from 96.3% to 98.9% for β-CM7. Intra-day precision was ranged between 7.3% and 22.7% for β-CM5; and 4.5% and 7.3% for β-CM7, meanwhile inter-day precision resulted 7.3%–16.5% for β-CM5 and 9.3%–12.8% for β-CM7. The concentration of β-CM5/7 was analyzed in different milk samples. β-CM7 was detected in 21 out of 30 samples and ranged from 0.76 to 8.41 ng/g milk, while β-CM5 was unequivocally identified in 3 samples, its concentration was 0.4–0.64 ng/g. This is the first report to describe the natural occurrence of β-CM5/7 in raw milk using LC-MS/MS. The present study provides evidence of β-CMs, especially β-CM7 that can be released in raw milk from different breeds.

Transformation of squalene and its by-products in latent fingermarks over time under different storage conditions (light, dark, and underwater) was examined through ultrahigh-performance liquid chromatography-high resolution accurate mass Orbitrap™ mass spectrometry. Complications of assessing fingermark compositional variation over time using multiple samples with varying initial compositions were elucidated and a more rational approach was successfully demonstrated. Squalene was detected in all fresh natural fingermarks deposited on non-porous surfaces and the amount ranged between 0.20 to 11.32 μg/5 fingertips. A notable difference in the transformation of squalene was observed with different storage conditions, where a dark aquatic environment accelerated degradation of squalene compared to dark but dry conditions. Squalene monohydroperoxide was extremely short-lived in natural deposits while the amount of squalene epoxide was still increasing relative to the initial amount, after ageing under dark and aquatic conditions for up to 7 days. Some oxidation by-products of cholesterol were also tentatively identified, which exhibited a growth over time against their initial concentration under any of the storage condition tested. These by-products, therefore, show potential as biomarkers for targeted visualisation of aged deposits.

This study investigated beta-casomorphin 7 (BCM7) in yogurt by means of LC-tandem MS (MS/MS) and enzyme-linked immunosorbent assay (ELISA) and use LC-MS/MS as the "gold standard" method to evaluate the applicability of a commercial ELISA. The level of BCM7 in milk obtained from ELISA analysis was much lower than that obtained by LC-MS/MS analysis and trended to increase during fermentation and storage of yogurt. Meanwhile, the results obtained from LC-MS/MS showed that BCM7 degraded during stages of yogurt processing, and its degradation may have been caused by X-prolyl dipeptidyl aminopeptidase activity. As a result, the commercial sandwich ELISA kit was not suitable for the quantification of BCM7 in fermented dairy milk.

Lead toxicity from ammunition has been shown to be a threat to scavenging birds across the globe. Despite decades of research in Europe, North and South America, Asia and Africa, there have been no studies to investigate this phenomenon in Australia despite that continent having many species of scavenging birds and widespread shooting practices. We present preliminary evidence of lead exposure in Australia's largest bird of prey, the wedge-tailed eagles (Aquila audax) through analysis of bone and eggshell samples from south-western Australia. From 11 bone samples, three birds (27%) had lead levels exceeding literature thresholds for elevated levels (>6.75 ppm). From 36 eggshell samples, no samples had lead levels >0.5 ppm, suggesting some limitations for this matrix as an indicator of lead exposure. Isotope ratios suggested ammunition as a likely source of the lead found in bone samples with elevated lead levels but other potential sources of lead require further investigation. Our preliminary results demonstrate that lead exposure is occurring in scavenging birds in Australia, and like the rest of the world, is likely to be derived from ammunition. This study supports an urgent call for further research into this worldwide phenomenon in Australia.

© 2019 Elsevier B.V. The quantitative variation in latent fingermark deposits sampled from the same donor (intra-donor) poses considerable challenges to studies into the chemical composition of latent fingermarks. The work presented here investigates approaches to the sampling of latent fingermark residues within this context. The amount of squalene in fingermarks deposited on non-porous surfaces, determined by GC–MS, was used as an indicator of the amount of non-polar material present. It was found that the percentage difference of squalene between deposits from two hands at a given time, without controlling the deposition force, was in the range of 4–100%. This was reduced to 0–44% in alternative sampling approaches where deposition force was controlled. These results demonstrate the significant influence of sampling on subsequent chemical analysis of fingermark residues, and offer possible sampling strategies to overcome issues associated with intra-donor variation.

Liquid chromatography-high resolution mass spectrometry (LC-HRMS) was used to investigate the degradation of β-casomorphin 5 (β-CM5) and β-casomorphin 7 (β-CM7) by Streptococcus thermophilus and/or Lactobacillus delbrueckii ssp. bulgaricus, and to identify the degradation products forming during yoghurt processing. Bovine UHT milk was fermented with: (i) a single strain of L. delbrueckii ssp. bulgaricus, (ii) a single strain of S. thermophilus and (iii) the mixture of S. thermophilus and L. delbrueckii ssp. bulgaricus to pH 4.5 and then stored at 4 °C for 1 and 7 days. Results showed that L. delbrueckii ssp. bulgaricus and/or S. thermophilus completely degraded β-CM5 and β-CM7 upon fermentation to pH 4.5 and degradation products were significantly influenced by bacteria strains and storage time. Four peptides, β-CNf60–61 (YP), β-CNf62–63 (FP), β-CNf64–66 (GPI) and β-CNf62–66 (FPGPI) were tentatively identified through high resolution MS/MS experiments; however, it was not possible to confirm if either milk protein or β-casomorphins was a source releasing these peptides. Nonetheless, in this study peptides YP and GPI were released by L. delbrueckii ssp. bulgaricus. This is the first time GPI has been identified and thus future investigation of its bioactivity is warranted.

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. Laboratory formation potential experiments showed that carboxylic acids can form from the degradation of aldehydes and nitriles. Volatile carboxylic acids could result in odour issues and some carboxylic acids may be of potential health concern. Therefore, carboxylic acids should also be considered as potential by-products of interest in distribution systems with long contact times of = 7days. A higher proportion of nitrile formation, and promotion of carboxylic acid formation, was observed when the chlorine to AA ratio was greater than 4 compared to when this ratio was 2.8, indicating that the Cl:AA ratio is an important factor in DBP formation pathways. This suggests that results from laboratory formation studies undertaken at these low Cl:AA ratios cannot be directly applied to ‘real’ water systems, which typically have Cl:AA ratios that are orders of magnitude higher than 4. Laboratory formation potential experiments also showed that the short-term rate of formation of aldehydes and N-chloraldimines was reduced in the presence of ammonia, although formation over longer timescales (e.g. 7 days) was not significantly different between chlorination and chloramination experiments. Therefore, the use of chloramination instead of chlorination do

© 2017 Elsevier Ltd Liquid chromatography-high resolution mass spectrometry (LC-HRMS) was used to investigate the degradation of ß-casomorphin 5 (ß-CM5) and ß-casomorphin 7 (ß-CM7) by Streptococcus thermophilus and/or Lactobacillus delbrueckii ssp. bulgaricus, and to identify the degradation products forming during yoghurt processing. Bovine UHT milk was fermented with: (i) a single strain of L. delbrueckii ssp. bulgaricus, (ii) a single strain of S. thermophilus and (iii) the mixture of S. thermophilus and L. delbrueckii ssp. bulgaricus to pH 4.5 and then stored at 4 °C for 1 and 7 days. Results showed that L. delbrueckii ssp. bulgaricus and/or S. thermophilus completely degraded ß-CM5 and ß-CM7 upon fermentation to pH 4.5 and degradation products were significantly influenced by bacteria strains and storage time. Four peptides, ß-CNf60–61 (YP), ß-CNf62–63 (FP), ß-CNf64–66 (GPI) and ß-CNf62–66 (FPGPI) were tentatively identified through high resolution MS/MS experiments; however, it was not possible to confirm if either milk protein or ß-casomorphins was a source releasing these peptides. Nonetheless, in this study peptides YP and GPI were released by L. delbrueckii ssp. bulgaricus. This is the first time GPI has been identified and thus future investigation of its bioactivity is warranted.

This study investigated beta-casomorphin 7 (BCM7) in yogurt by means of LC-tandem MS (MS/MS) and enzyme-linkedimmunosorbent assay (ELISA) and use LC-MS/MS as the "gold standard" method to evaluate the applicability of a commercial ELISA. The level of BCM7 in milk obtained from ELISA analysis was much lower than that obtained by LC-MS/MS analysis and trended to increase during fermentation and storage of yogurt. Meanwhile, the results obtained from LC-MS/MS showed that BCM7 degraded during stages of yogurt processing, and its degradation may have been caused by X-prolyl dipeptidyl aminopeptidase activity. As a result, the commercial sandwich ELISA kit was not suitable for the quantification of BCM7 in fermented dairy milk.

Simple, fast and low cost methods for the detection of sulfate are required for different applications. Electrochemistry at water/o-nitrophenyloctylether (W/NPOE) interfaces was employed to evaluate sulfate detection by ionophore-facilitated ion-transfer at an array of micro-interfaces. With ionophore 1,3-[Bis(3-phenylthioureidomethyl)]benzene present in the NPOE phase, the transfer of sulfate across the interface was determined by voltammetry at ca. - 0.35 V for 0.01 M Na2SO4 on the Galvani potential scale. The potentiometric detection limit for sulfate was 0.6 × 10- 6 M, based on the shift in the half-wave transfer potential with concentration. Amperometric detection limits for forward and reverse ion transfer currents were determined to be 14 × 10- 6 M and 0.8 × 10- 6 M, respectively. Electrochemical analysis of the half-wave potential versus logCSO42 -w and the corresponding electrospray ionisation – high resolution mass spectrometry (ESI-HRMS) analysis of W/NPOE emulsions indicated interfacial complexation via the formation of 1:1 sulfate:ionophore complexes. ESI-HRMS analysis of W/NPOE emulsions formed with water samples from an advanced water treatment plant revealed the binding of the ionophore to potential interferences from this environment, thus providing a guide to sensor development.

In this report, we summarise collected data on the occurrence and removal of several anthropogenic chemicals in Western Australian Waste Water Treatment Plants (WWTPs) that differ in geographical location and design. Treatment efficiency was also characterised by monitoring nutrient concentrations. A wide variety of anthropogenic compounds were detected in the WWTPs. Wastewater treatments reduced the concentrations of some of these chemicals to varying extents, while other chemicals were persistent through treatment. While there was no consistent pattern in chemical removal at different WWTPs, preliminary results indicate that the simple pond systems generally performed less effectively compared to oxidation ditch and combined pond systems. Multivariate analysis of the DNA sequencing results indicated that microbiomes (i.e., the microbial DNA) associated with the treatment plants could be differentiated based on location, treatment stage and treatment technology. For 3 out of the 4 plants (WWTP 1, WWTP 3, WWTP 4), all influents were similar, but microbial communities after treatment varied widely, depending on the location or technology. The microbial community of WWTP 2 influent was different from the other treatment plants and the microbial profile remained similar even after treatment.

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. They are potentially harmful to humans and may exist as an intermediate for other disinfection by-products. However, little information is available on the formation or occurrence of organic chloramines in water due to a number of challenges. One of the biggest challenges for the identification and quantification of organic chloramines in water systems is the lack of appropriate analytical methods. In addition, many of the organic chloramines that form during disinfection are unstable, which results in difficulties in sampling and detection. To date research has focussed on the study of organic monochloramines. However, given that breakpoint chlorination is commonly undertaken in water treatment systems, the formation of organic dichloramines should also be considered. Organic chloramines can be formed from many different precursors and pathways. Therefore, studying the occurrence of their precursors in water systems would enable better prediction and management of their formation.

Milk proteins including casein are sources of peptides with bioactivity. One of these peptides is beta-casomorphin (BCM) which belongs to a group of opioid peptides formed from β-casein variants. Beta-casomorphin 7 (BCM7) has been demonstrated to be enzymatically released from the A1 or B β-casein variant. Epidemiological evidence suggests the peptide BCM 7 is a risk factor for development of human diseases, including increased risk of type 1 diabetes and cardiovascular diseases but this has not been thoroughly substantiated by research studies. High performance liquid chromatography coupled to UV-Vis and mass spectrometry detection as well as enzyme–linked immunosorbent assay (ELISA) has been used to analyze BCMs in dairy products. BCMs have been detected in raw cow's milk and human milk and a variety of commercial cheeses, but their presence has yet to be confirmed in commercial yoghurts. The finding that BCMs are present in cheese suggests they could also form in yoghurt, but be degraded during yoghurt processing. Whether BCMs do form in yoghurt and the amount of BCM forming or degrading at different processing steps needs further investigation and possibly will depend on the heat treatment and fermentation process used, but it remains an intriguing unknown.

Beta-casomorphin 5 (BCM5) and beta-casomorphin 7 (BCM7) in 14 commercial pasteurised milks from around Australia were investigated using liquid chromatography–tandem mass spectrometry (LC–MS/MS) and liquid chromatography–high resolution (Orbitrap) mass spectrometry (LC–HRMS). Collision induced dissociation HRMS was used to confirm the presence of BCM7 in milk extracts. The accurate mass-to-charge ratio (m/z) and relative abundance of BCM7 parent ion and fragments in milk extracts matched with those obtained from the analysis of a BCM7 standard solution. The deviation against the theoretical values of the measured m/z of BCM7 (parent ion and fragments) all gave results below 5 ppm (relative error). BCM5 was below limit of detection (LOD) for all milks, while BCM7 was between 0.13 and 2.38 ng/g in 10 milks and below LOD in the others. Pasteurised milks containing the highest and lowest BCM7 levels were produced in Western Australia.

Beta-casomorphin 5 (BCM5) and beta-casomorphin 7 (BCM7) in 14 commercial pasteurised milks from around Australia were investigated using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and liquid chromatography-high resolution (Orbitrap) mass spectrometry (LC-HRMS). Collision induced dissociation HRMS was used to confirm the presence of BCM7 in milk extracts. The accurate mass-to-charge ratio ( m/ z) and relative abundance of BCM7 parent ion and fragments in milk extracts matched with those obtained from the analysis of a BCM7 standard solution. The deviation against the theoretical values of the measured m/ z of BCM7 (parent ion and fragments) all gave results below 5. ppm (relative error). BCM5 was below limit of detection (LOD) for all milks, while BCM7 was between 0.13 and 2.38 ng/g in 10 milks and below LOD in the others. Pasteurised milks containing the highest and lowest BCM7 levels were produced in Western Australia.

Removal of organic micropollutants from wastewater during secondary treatment followed by reverse osmosis and UV disinfection was evaluated by a combination of four in-vitro cell-based bioassays and chemical analysis of 299 organic compounds. Concentrations detected in recycled water were below the Australian Guidelines for Water Recycling. Thus the detected chemicals were considered not to pose any health risk. The detected pesticides in the wastewater treatment plant effluent and partially advanced treated water explained all observed effects on photosynthesis inhibition. In contrast, mixture toxicity experiments with designed mixtures containing all detected chemicals at their measured concentrations demonstrated that the known chemicals explained less than 3% of the observed cytotoxicity and less than 1% of the oxidative stress response. Pesticides followed by pharmaceuticals and personal care products dominated the observed mixture effects. The detected chemicals were not related to the observed genotoxicity. The large proportion of unknown toxicity calls for effect monitoring complementary to chemical monitoring.