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∑QNs in the water-sediment system exhibited decreasing trends from northwest (NW) to southeast (SE) in both periods; however, the Koc (organic carbon normalized partition coefficients) of individual QNs in DP sharply rose compared with those in NDP, which indicated that water diversion would alter the environmental fate of QNs in Luoma Lake. In DP, all QNs, excluding NOR, were all biodiluted across the food web; whereas their bioaccumulation potentials in the SE subregion were higher than those in the NW subregion, which was in contrast to the spatial distribution of their exposure concentrations. The estimated daily QN intakes via drinking water and aquatic products suggested that residents in the SE side were exposed to greater health risks, despite less aquatic pollution in the region.Total suspended particulate (TSP) and PM10 filters collected from two ambient air monitoring stations in Port Pirie were analysed to determine the impact of a lead (Pb) smelter redevelopment on air quality parameters including total elemental concentration, Pb isotopic ratio, Pb bioaccessibility and Pb speciation. Filters from 2009 to 2020 were analysed with a focus on samples from 2017 (immediately prior to smelter redevelopment) and 2020 (post-smelter redevelopment). Lead concentration in 2009-2020 TSP was variable ranging up to 6.94 μg m-3 (mean = 0.57 μg m-3), however, no significant decrease in Pb concentration was observed at either Port Pirie West (p = 0.56, n = 34) or Oliver Street (p = 0.32, n = 28) monitoring stations when 2017 and 2020 TSP values were compared. Similarly, no significant difference (p = 0.42) in PM10 Pb concentration was observed in 2017 (mean = 0.80 μg m-3) and 2020 (0.60 μg m-3) Oliver Street filters. Although no change in percentage Pb bioaccessibility was observed when 2017 and 2020 Port Pirie West TSP samples were compared (mean of 88.7% versus 88.0%), Pb bioaccessibility was lower (p less then 0.005) in both 2020 TSP (mean of 83.9% versus 62.9%) and PM10 (mean of 70.8% versus 58.3%) Oliver Street filters compared to 2017. While scanning electron microscopy, energy dispersive x-ray spectroscopy identified a number of Pb phases within filters (galena, anglesite, cerussite, conglomerates), differences in Pb speciation between 2017 and 2020 filters could not be identified although it was presumed that this influenced Pb bioaccessibility outcomes at Oliver Street. Data from this study suggests that recent smelter redevelopments have not significantly decreased the concentrations of airborne Pb in Port Pirie although re-entrainment of soil-Pb from historical impact may also be a contributing Pb source.The installation of marine renewable energy devices (MREDs, wind turbines and converters of wave, tidal and ocean thermal energy) has increased quickly in the last decade. There is a lack of knowledge concerning the effects of MREDs on benthic invertebrates that live in contact with the seabed. The European common cuttlefish (Sepia officinalis) is the most abundant cephalopod in the Northeast Atlantic and one of the three most valuable resources for English Channel fisheries. A project to build an offshore wind farm in the French bay of Saint-Brieuc, near the English Channel, raised concern about the possible acoustic impact on local cuttlefish communities. In this study, consisting of six exposure experiments, three types of noise were considered 3 levels of pile-driving and 3 levels of drilling. The objectives were to assess possible associated changes in hatching and larva survival, and behavioural and ultrastructural effects on sensory organs of all life stages of S. officinalis populations. After exposure, damage was observed in the statocyst sensory epithelia (hair cell extrusion) in adults compared to controls, and no anti-predator reaction was observed. The exposed larvae showed a decreased survival rate with an increasing received sound level when they were exposed to maximum pile-driving and drilling sound levels (170 dB re 1 μPa2 and 167 dB re 1 μPa2, respectively). However, sound pressure levels's lower than 163 dB re 1 μPa2 were not found to elicit severe damage. Simulating a scenario of immobile organisms, eggs were exposed to a combination of both pile driving and drilling as they would be exposed to all operations without a chance to escape. In this scenario a decrease of hatching success was observed with increasing received sound levels.Carbonaceous aerosols pose significant climatic impact, however, their sources and respective contribution to light absorption vary and remain poorly understood. In this work, filter-based PM2.5 samples were collected in winter of 2021 at three urban sites in Yibin, a fast-growing city in the south of Sichuan Basin, China. The composition characteristics of PM2.5, light absorption and source of carbonaceous aerosol were analyzed. The city-wide average concentration of PM2.5 was 87.4 ± 31.0 μg/m3 in winter. Carbonaceous aerosol was the most abundant species, accounting for 42.5% of the total PM2.5. Source apportionment results showed that vehicular emission was the main source of PM2.5 during winter, contributing 34.6% to PM2.5. The light absorption of black carbon (BC) and brown carbon (BrC) were derived from a simplified two-component model. We apportioned the light absorption of carbonaceous aerosols to BC and BrC using the Least Squares Linear Regression with optimal angstrom absorption exponent of BC (AAEBC). The average absorption of BC and BrC at 405 nm were 51.6 ± 21.5 Mm-1 and 17.7 ± 8.0 Mm-1, respectively, with mean AAEBC = 0.82 ± 0.02. The contribution of BrC to the absorption of carbonaceous reached 26.1% at 405 nm. Based on the PM2.5 source apportionment and the mass absorption cross-section (MAC) value of BrC at 405 nm, vehicle emission was found to be the dominant source of BrC in winter, contributing up to 56.4%. Therefore, vehicle emissions mitigation should be the primary and an effective way to improve atmospheric visibility in this fast-developing city.Two kinds of C8 isomers, di-n-butyl ether (DNBE) and 1-octanol, as potential oxygen-containing alternative fuels, show important value in the trade-off between efficiency and emission. In the present work, the effects of DNBE/1-octanol with different proportions (0, 10%, and 20%) blended into diesel on the combustion characteristics, fuel economy, and emission characteristics in a six-cylinder heavy-duty diesel engine were studied at low, medium, and high loads. 1-Octanol with a 20% blending ratio showed different combustion characteristics in the cylinder compared with the other fuels. Protosappanin B nmr The economic analysis showed that the brake specific fuel consumption of DNBE-diesel blend fuels was higher than that of 1-octanol-diesel blend fuels, while brake thermal efficiency was the opposite tendency. The emissions of nitrogen oxides (NOx), hydrocarbons (HC), and carbon monoxide (CO) were affected by the types of blend fuels, blending ratios, and loads. In comparison with 1-octanol-diesel blend fuels, the addition of DNBE in diesel promoted the emission of nitrogen oxides, but inhibited the emissions of soot, HC, and CO. DNBE- and 1-octanol-diesel blend fuels increased the weighted brake specific fuel consumption but decreased the weighted brake thermal efficiency compared with diesel in the World Harmonized Stationary Cycle test cycle of Euro VI regulation. The weighted NOx, HC, soot, and CO emissions of blend fuels depended on the types of blend fuels and blend ratios. The weighted NOx, HC, and soot emissions were reduced by blending 1-octanol into diesel, while the weighted CO emission was increased. The weighted CO and soot emissions of diesel blended with DNBE were reduced than that of diesel.Per- and polyfluorinated alkyl substances (PFAS) are highly persistent chemicals, which pose a potential risk for aquatic wildlife due to their bioaccumulative behaviour and toxicological effects. Although the distribution of PFAS in marine environments has been studied worldwide, little is known on the contamination of PFAS in the southern North Sea. In the present study, the bioaccumulation and trophic transfer of Perfluoroalkyl acids (PFAAs) was studied in liver and muscle tissue of seven fish species and in whole-body tissue of two crustacean species, collected at 10 sites in the Belgian North Sea. Furthermore, the human and ecological health risks were examined. Overall, perfluorooctane sulfonate (PFOS) was predominant in all matrices and other long-chain PFAS were frequently detected. Mean PFOS concentrations ranged from less then LOQ to 107 ng/g (ww) in fish liver, from less then LOQ to 24 ng/g ww in fish muscle and from 0.29 to 5.6 ng/g ww in crustaceans. Elevated perfluorotridecanoic acid (PFTrDA) concentrations were detected in fish liver from the estuarine and coastal region ( less then LOQ-116 ng/g ww), indicating a specific point source of this compound. Based on stable isotope analysis, no distinctive trophic transfer patterns of PFAS could be identified which implies that the bioconcentration of PFAS from the surrounding abiotic environment is most likely dominating over the biomagnification in the studied biota. The consumption of commercially important species such as the brown shrimp (Crangon crangon), plaice (Pleuronecta platessa), sole (Solea solea) and whiting (Merlangus merlangus) might pose potential health risks if it exceeds 17 g/day, 18 g/day, 26 g/day and 43 g/day respectively. Most PFOS measurements did not exceed the QSbiota,hh of 9.1 ng/g ww, however, the benchmark of 33 ng/g ww targeting the protection of wildlife from secondary poisoning was exceeded for 43% and 28% of the samples in plaice and sole.China has been in a rapid development period in recent decades, the mass production and use of chemical industrial products and pesticides have resulted in a large amount of pollutants in the environment. These pollutants enter the human body through environmental exposure and dietary intake, causing adverse health effects. Although many of them have been banned and restricted in the production and use in China, these pollutants still remain in the human body due to their high persistence and strong bioaccumulation. In this review, we aim to reveal the accumulation levels and profiles, as well as the temporal and spatial distribution of common chemical pollutants including chlorinated paraffins (CPs), polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers, organophosphorus flame retardants (OPFRs), new halogenated flame retardants (NHFRs), polychlorinated biphenyls, phthalic acid esters, perfluorinated compounds, bisphenols, organophosphorus pesticides and pyrethroid insecticides in the blood (including whole blood, serum and plasma) of Chinese adults by extracting 93 related studies published from 1990 to 2021. Results have shown that CPs, OCPs and PAHs were the main pollutants in China, the levels of short-chain chlorinated paraffin, p,p'-DDE and phenanthrene in blood even reached 11,060.58, 740.41 and 498.28 ng/g lipid respectively. Under the strict control of pollutants in China, the levels of most pollutants have been on a downward trend except for perfluoro octanoate and perfluoro nonanoate. Besides, OPFRs, NHFRs and PAHs may have a potential upward trend, requiring further research and observation. As for spatial distribution, East China (Bohai Bay and Yangtze River Delta) and South China (Pearl River Delta) were the major polluted regions due to their fast development of industry and agriculture.

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