There were several studies that measured organophosphate esters (OPEs) in foods to assess the dietary intake of OPEs but none has measured OPE metabolites (mOPEs) in the same samples. In this study, we measured the concentrations of OPEs and mOPEs in 87 food samples and in five tap water samples collected in Queensland, Australia belonging to eight food groups. Tris(2-chloroisopropyl) phosphate (TCIPP) (detection frequency (DF), 77%) and tributyl phosphate (TBP) (DF, 71%), were the most frequently detected OPEs, while dibutyl phosphate (DBP) (DF, 84%) and diphenyl phosphate (DPhP) (DF, 86%) were the most frequently detected mOPEs. Vegetables had the highest concentrations of both ∑ 9 OPEs and ∑ 11 mOPEs, with the mean concentrations of 2.6 and 17 ng/g wet weight. Compared with dust ingestion and inhalation, dietary intake was the most important exposure pathway for tris(2-chloroethyl) phosphate (TCEP) (4.1 ng/kg bw/day), TCIPP (25 ng/kg bw/day), and TBP (6.7 ng/kg bw/day), accounting for >75% of total intake. Furthermore, we found that the intakes of some mOPEs, that is, bis(1,3-dichloroisopropyl) phosphate (BDCIPP) and DPhP from diet were typically higher than that of their parent OPEs. Such high levels of mOPE intakes could interfere with the utilization of mOPEs as biomarkers for assessing OPE exposure and warrant further investigation.

Plastics are contaminants of emerging concern that can enter the environment from multiple sources, including via land application of treated sewage sludge (biosolids). Biosolids samples collected from 82 wastewater treatment plants (WWTPs) across Australia and covering 34% of the population during census week in 2016 were quantitatively analyzed to estimate the release of seven common plastics. Quantitative analysis was performed by pressurized liquid extraction followed by double-shot microfurnace pyrolysis coupled to gas chromatography mass spectrometry. Ninety nine percent of the samples contained plastics (Σ 6 plastics) at concentrations of between 0.4 and 23.5 mg/g dry weight (median; 10.4 mg/g dry weight), while polycarbonate was not detected in any sample. Per-capita mass loads of plastics (Σ 6 plastics) released were between 8 and 877 g/person/year across all investigated WWTPs. Polyethylene was the predominant plastic detected, contributing to 69% of Σ 6 plastics. Based on the concentrations measured, it was projected that around 4700 metric tons (Mt) of plastics are released into the Australian environment through biosolids end-use each year, equating to approximately 200 g/person/ year, which represents 0.13% of total plastics use in Australia. Of this, 3700 Mt of plastics are released to agricultural lands and 140 Mt to landscape topsoil. Our results provide a first quantitative per-capita mass loads and emission estimate of plastic types through biosolids end-use.

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Observations of Kuiper belt objects (KBOs) in Neptune's 5:2 resonance present two puzzles: this third order resonance hosts a surprisingly large population, comparable to the prominent populations of Plutinos and Twotinos in the first order 3:2 and 2:1 resonances, respectively; secondly, their eccentricities are concentrated near 0.4. To shed light on these puzzles, we investigate the phase space near this resonance with use of Poincaré sections of the circular planar restricted three body model. We find several transitions in the phase space structure with increasing eccentricity, which we explain with the properties of the resonant orbit relative to Neptune's. The resonance width is narrow for very small eccentricities, but widens dramatically for e 0.2, reaching a maximum near e ≈ 0.4, where it is similar to the maximum widths of the 2:1 and 3:2 resonances. We confirm these results with N-body numerical simulations, including the effects of all four giant planets and a wide range of orbital inclinations of the KBOs. We find that the boundaries of the stable resonance zone are not strongly sensitive to inclination and remain very similar to those found with the simplified three body model, with the caveat that orbits of eccentricity above ∼ 0.53 are unstable; higher eccentricity orbits are phase-protected from destabilizing encounters with Neptune but not with Uranus. These results show that the 5:2 resonant KBOs are not more puzzling than the Plutinos and Twotinos; however, detailed understanding of the origins of eccentric, inclined resonant KBOs remains a challenge.

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We report the first confirmation of a hot Jupiter discovered by the Transiting Exoplanet Survey Satellite (TESS ) mission: HD 202772A b. The transit signal was detected in the data from TESS Sector 1, and was confirmed to be of planetary origin through radial velocity (RV) measurements. HD 202772A b is orbiting a mildly evolved star with a period of 3.3 days. With an apparent magnitude of V = 8.3, the star is among the brightest known to host a hot Jupiter. Based on the 27 days of TESS photometry, and RV data from the CHIRON and HARPS spectrographs, the planet has a mass of 1.008 +0.074 −0.079 M J and radius of 1.562 +0.053 −0.069 R J , making it an inflated gas giant. HD 202772A b is a rare example of a transiting hot Jupiter around a quickly evolving star. It is also one of the most strongly irradiated hot Jupiters currently known.

Mean motion resonances [MMRs] play an important role in the formation and evolution of planetary systems and have significantly influenced the orbital properties and distribution of planets and minor planets in the solar system as well as exo-planetary systems. Most previous theoretical analyses have focused on the low-to-moderate eccentricity regime, but with new discoveries of high eccentricity resonant minor planets and even exoplanets, there is increasing motivation to examine MMRs in the high eccentricity regime. Here we report on a study of the high eccentricity regime of MMRs in the circular planar restricted three-body problem. Non-perturbative numerical analyses of the 2:1 and the 3:2 interior resonances are carried out for a wide range of secondary-to-primary mass ratio, and for a wide range of eccentricity of the test particle. The surface-of-section technique is used to study the phase space structure near resonances. We identify transitions in phase space at certain critical eccentricities related to the geometry of resonant orbits; new stable libration zones appear at high eccentricity at libration centers shifted from those at low eccentricities. We present novel results on the mass and eccentricity dependence of the resonance libration centers and their widths in semi-major axis. Our results show that MMRs have sizable libration zones at high eccentricities, comparable to those at lower eccentricities.