The response of sediment bacterial communities in subtropical freshwater benthic microcosms to sediment-associated triclosan (TCS; 28 d exposure) was analysed using Illumina high-throughput sequencing. This study highlights the interactive effects of TCS and the presence of benthic macroinvertebrates (Limnodrilus hoffmeisteri and Viviparidae bellamya) on sediment bacterial communities. Our results show that TCS alone significantly altered the taxonomic composition and decreased alpha diversity of sediment bacterial communities at concentrations ≥80 μg TCS/g dry weight (dw) sediment (sed). Regarding dominant phyla, TCS significantly reduced the relative abundance of Bacteroidetes and Firmicutes at these concentrations, whereas the relative abundance of Chloroflexi and Cyanobacteria increased. In the presence of benthic macroinvertebrates, the sediment bacterial community was affected by 8 μg TCS/g dw sed as well. However, the presence of benthic macroinvertebrates did not cause measurable changes to bacterial community in unspiked (i.e., control) sediment. These results indicate that TCS alone would not alter the sediment bacterial community at environmentally relevant concentrations (up till 8 μg/g dw sed), but may have an effect in combination with the presence of benthic macroinvertebrates. Therefore, we recommend to include benthic macroinvertebrates when assessing the response of sediment bacterial communities during exposure to environmental stress such as organic contaminants.

Propylea japonica is a very important predator in agricultural ecosystems, which could be exposed to Bt protein. In this study, the bacterial community of P. japonica fed with normal food and food containing Cry2Ab protein was characterized for the first time using qPCR and high-throughput sequencing approaches. Results showed no effect of Cry2Ab on P. japonica development and reproduction. The most abundant bacterial phylum was Firmicutes, and the most abundant genus was Staphylococcus. The total bacteria copy number was not significantly different across four larval stages. Bacteria species composition was gathered more closely in feed on sucrose solution (sucrose-fed) than in larvae only fed on pea aphid (aphid-fed), the diversity indices of some operational taxonomic unit (OTU) were significantly different between sucrose-fed and aphid-fed samples. Different instar larval stages of P. japonica fed with sucrose solution containing Cry2Ab Bt protein and found no effect on microbial community composition and total bacteria copy numbers. However, effects on relative abundance of microbes, copy numbers of Corynebacterium 1 and Glutamicibacter arilaitensis were observed significantly lower in Bt-fed first and fourth larval stages. Low and high concentrations of Cry2Ab protein altered the microbial abundance relative to sucrose-fed P. japonica and copy numbers of G. arilaitensis and Staphylococcus xylosus were significantly lower in Bt-fed samples than control sucrose-fed. Our results are the first report showing that feeding on Cry2Ab protein does not alter microbial species composition in P. japonica, but effects gene copy number of some dominant bacteria. Further investigations are needed to assess the effect of copy number change on P. japonica.

Hexabromocyclododecane (HBCD) is commonly used in commercial products and factories. HBCDs can be detected in the air, bioaccumulated deposits, water, soil, sediments, and in biota and foodstuffs in the food-chain because they are not chemically bound to the polymer. We determined the levels of α-, β-, and γ-HBCDs in 270 foodstuffs and the doses of HBCDs Taiwanese are normally exposed to. We also wanted to create a strategy of risk management for HBCDs based on margins of exposure (MOE). HBCDs were frequently detectible in fish, seafood, and poultry. Their highest concentrations were in fish, oil, poultry, and livestock. The highest estimated daily intake was in 0- to 3-year-olds (1.576 ng/kg/day), and lower in 3- to 6- (1.064 ng/kg/day), 6- to 12- (0.899 ng/kg/day), and lowest in 12- to 16- (0.632 ng/kg/day) year-olds. The exposure doses to HBCDs indicated no health concern for Taiwanese. Except for fish, significant concentrations of α- and γ-HBCDs were detected in many other foodstuffs, which might indicate that exposure to HBCD is a relatively recent problem. Therefore, one goal of a management policy should be to follow-up the flow direction of HBCDs in Taiwan.

A number of systematic reviews have investigated the association between air pollutants and health impacts, these mostly focus on morbidity and mortality from hospital data. Previously, no reviews focused solely on ambulance dispatch data. These data sets have excellent potential for environmental health research. For this review, publications up to April 2019 were identified using three main search categories covering: ambulance services including dispatches; air pollutants; and health outcomes. From 308 studies initially identified, 275 were excluded as they did not relate to ambulance service dispatches, did not report the air pollutant association, and/or did not study ambient air pollution. The main health outcomes in the remaining 33 studies were cardiac arrest (n = 14), cardiovascular (n = 11) and respiratory (n = 10) dispatches. Meta-analyses were performed to summarise pooled relative risk (RR) of pollutants: particulate matter less than 2.5 and 10 μm (PM₂.₅, PM₁₀), the fraction between PM₁₀ and PM₂.₅ (coarse) and suspended particulate matter (SPM) per 10 μg/m³ increase, carbon monoxide (CO) per 1 ppm increase and of sulphur dioxide (SO₂), nitrogen dioxide (NO₂), and ozone (O₃) per 10 ppb increment and ambulance dispatches. Statistically significant associations were found for ambulance dispatch data for all-respiratory and PM₂.₅ at 1.03 (95% CI:1.02–1.04) and at 1.10 (95% CI:1.00–1.21) for asthma and NO₂ associations. For dispatches with subsequent paramedic assessment for cardiac arrest with PM₂.₅, CO and coarse dispatches at 1.05 (95% CI:1.03–1.08), 1.10 (95% CI:1.02–1.18) and 1.04 (95% CI:1.01–1.06) respectively. For dispatches with subsequent physician diagnosis for all-respiratory and PM₂.₅ at 1.02 (95% CI:1.01–1.03). In conclusion, air pollution was significantly associated with an increase in ambulance dispatch data, including those for cardiac arrest, all-respiratory, and asthma dispatches. Ambulance services should plan accordingly during pollution events. Furthermore, efforts to improve air quality should lead to decreases in ambulance dispatches.

The immunotoxicity of synthetic pyrethroid (SPs) has garnered much attention, and our previous research demonstrated that β-CYP causes immunotoxicity and oxidative stress in macrophages. Nevertheless, the underlying mechanism remains largely unknown. In this study, the murine macrophage RAW 264.7 cells and murine peritoneal macrophages (PMs) were exposed to β-CYP. The results showed that β-CYP elevated intracellular ROS levels in both RAW 264.7 cells and PMs. Exposure to β-CYP also caused mitochondrial dysfunction with reduced mitochondrial membrane potential (MMP), intracellular ATP level and mitochondrial DNA (mtDNA) content in the two cell types. In addition, exposure of RAW 264.7 cells to β-CYP for 12 h and 24 h enhanced autophagy, with elevated Beclin1, Rab7, Lamp1 and LC3-II expression levels, while 48 h of exposure attenuated autophagy. In contrast, exposure of PMs to β-CYP for 12 h promoted autophagy, whereas exposure for 24 h and 48 h impaired autophagy. Cotreatment with an antioxidant, N-acetyl-L-cysteine (NAC), partially blocked the reduced MMP, intracellular ATP level and autophagy disturbance. Moreover, cotreatment with an autophagy agonist, rapamycin (RAPA), partially blocked mitochondrial dysfunction and oxidative stress in the two cell types, whereas cotreatment with an autophagy inhibitor, 3-methyladenine (3-MA), augmented the abovementioned toxic effects. Furthermore, mitochondrial ROS levels in both RAW 264.7 cells and PMs were elevated by exposure to β-CYP, and molecular docking showed that β-CYP docked with mouse respiratory chain complex I by binding to the ND2, ND4, and ND5 subunits of the protein complex. Taken together, the data obtained in the present study demonstrate that oxidative stress partially mediates mitochondrial dysfunction and autophagy disturbance upon exposure to β-CYP in macrophages, and autophagy plays a protective role against the toxic effects.

The effect of different Na concentrations on the fate of trace metals (Cd, Cu, Ni, Zn) in standard OECD soil was evaluated by performing soil leaching column experiments. Five Na concentrations added in synthetic irrigation water (0, 1, 5, 10, 50 mM) were studied in order to evaluate the fate of the metals contained in both the irrigation water leachate and the soil layer. In all experiments, metals mostly accumulated on the top soil layer (0–0.5 cm), at variable concentrations according to the Na content in the artificial irrigation water. Nevertheless, concentration peaks of metal contamination occurred at different sampling time in the soil leachates depending on the metal and on influent water sodicity. Peaks of metals in the leachate appeared simultaneously with the release of organic matter and/or release of Al, suggesting significant involvement of colloids in metals transport. Sodium concentration (10–50 mM) was demonstrated to highly reduce colloidal mobilization leading to the accumulation of more than 95% of the influent metal in the top soil layer. Conversely, low Na concentrations (1–5 mM) favored colloidal transport leading to the recovery of metals in the soil leachates.

The transport and retention behavior of polymer- (PVP-AgNP) and surfactant-stabilized (AgPURE) silver nanoparticles in carbonate-dominated saturated and unconsolidated porous media was studied at the laboratory scale. Initial column experiments were conducted to investigate the influence of chemical heterogeneity (CH) and nano-scale surface roughness (NR) arising from mixtures of clean, positively charged calcium carbonate sand (CCS), and negatively charged quartz sands. Additional column experiments were performed to elucidate the impact of CH and NR arising from the presence and absence of soil organic matter (SOM) on a natural carbonate-dominated aquifer material. The role of the nanoparticle capping agent was examined under all conditions tested in the column experiments. Nanoparticle transport was well described using a numerical model that facilitated blocking on one or two retention sites. Results demonstrate that an increase in CCS content in the artificially mixed porous medium leads to delayed breakthrough of the AgNPs, although AgPURE was much less affected by the CCS content than PVP-AgNPs. Interestingly, only a small portion of the solid surface area contributed to AgNP retention, even on positively charged CCS, due to the presence of NR which weakened the adhesive interaction. The presence of SOM enhanced the retention of AgPURE on the natural carbonate-dominated aquifer material, which can be a result of hydrophobic or hydrophilic interactions or due to cation bridging. Surprisingly, SOM had no significant impact on PVP-AgNP retention, which suggests that a reduction in electrostatic repulsion due to the presence of SOM outweighs the relative importance of other binding mechanisms. Our findings are important for future studies related to AgNP transport in shallow unconsolidated calcareous and siliceous carbonate sands.

A growing concern for contamination due to pharmaceutical compounds in groundwater is expanding globally.The β-blocker propranolol is a β-adrenoceptors antagonist commonly detected in European groundwater bodies. The effect of propranolol on stygobiotic species (obligate groundwater dweller species) is compelling in the framework of environmental risk assessment (ERA) of groundwater ecosystems. In fact, in Europe, ERA procedures for pharmaceuticals in groundwater are based on data obtained with surrogate surface water species. The use of surrogates has aroused some concern in the scientific arena since the first ERA guideline for groundwater was issued. We performed an ecotoxicological and a behavioural experiment with the stygobiotic crustacean species Diacyclops belgicus (Copepopda) to estimate a realistic value of the Predicted No Effect Concentration (PNEC) of propranolol for groundwater ecosystems and we compared this value with the PNEC estimated based on EU ERA procedures. The results of this study showed that i) presently, propranolol does not pose a risk to groundwater bodies in Europe at the concentrations shown in this study and ii) the PNEC of propranolol estimated through the EU ERA procedures is very conservative and allows to adequately protect these delicate ecosystems and their dwelling fauna. The methodological approach and the results of this study represent a first contribution to the improvement of ERA of groundwater ecosystems.

The majority of plastics present in the marine environment are microplastics (MPs, <5 mm). Suspension filter feeders are susceptible species to MPs ingestion. Once ingested MPs can be eliminated packed in fecal pellets, or they can be accumulated within tissues, and likely be transferred along the food web. The research on MPs is hampered by the difficulty on their quantification and the lack of standardized methodologies. Indeed, limited information exits about the capacity of marine organisms to ingest, accumulate and eliminate MPs. In this work we investigated the uptake, elimination and accumulation of MPs (irregularly shaped particles of high density polyethylene, ≤22 μm) in mussel. Mussels were exposed to two concentrations of MPs (2 and 4 mm3 l−1), and their uptake, elimination and accumulation in digestive gland was investigated. The results showed that the uptake of MPs increased at the high concentration tested, and that mussels cleared MPs at the same extent than a food item (microalgae) of similar size. Small MPs (2–4 μm) were less efficiently cleared than the larger ones. Large MPs (>10 μm) were faster eliminated than the smaller ones. The global balance showed that after 6 days of depuration mussels eliminated ≈85% of the MPs cleared, and that ≈2–6% of the MPs cleared remained in the digestive gland, essentially those <6 μm. We recorded a long retention time for MPs, contrasting with the lower times assumed to be necessary to empty mussel's gut before quantifying MPs. Our study emphasized the gap of knowledge on the feeding behaviour of mussels in relation to MPs, and the necessity to investigate it in different marine species, and under different exposure scenarios.

To identify the sources and heterogeneous reactions of sulfate and nitrate with dust in the atmosphere, airborne particles in Xi'an, inland China during the spring of 2017 were collected and measured for chemical compositions, along with a laboratory simulation of the heterogeneous formation of ammonium nitrate on the dust surface. Our results showed that concentrations of Ca²⁺, Na⁺ and Cl⁻ in the TSP samples were enhanced in the dust events, with the values of 41.8, 5.4 and 4.0 μg m⁻³, respectively, while NO₃⁻ (7.1 μg m⁻³) and NH₄⁺ (2.4 μg m⁻³) remarkably decreased, compared to those in the non-dust periods. During the dust events, NH₄⁺ correlated only with NO₃⁻ (R² = 0.52) and abundantly occurred in the coarse mode (>2.1 μm), in contrast to that in the non-dust periods, which well correlated with sulfate and nitrate and enriched in the fine mode (<2.1 μm). SO₄²⁻ in Xi'an during the dust events existed mostly as gypsum (CaSO₄·2H₂O) and mirabilite (Na₂SO₄·10H₂O) and dominated in the coarse mode, suggesting that they were directly transported from the upwind Gobi Desert region. Our laboratory simulation results showed that during the long-range transport hygroscopic salts in the Gobi dust such as mirabilite can absorb water vapor and form a liquid phase on the particle surface, then gaseous NH₃ and HNO₃ partition into the aqueous phase and form NH₄NO₃, resulting in the strong correlation of NH₄⁺ with NO₃⁻ and their accumulation on dust particles. The dry deposition flux of total inorganic nitrogen (NH₄⁺ + NO₃⁻) in Xi'an during the dust events was 0.97 mg-N m⁻² d⁻¹ and 37% higher than that in the non-dust periods. Such a significant enhanced N-deposition is ascribed to the heterogeneous formation of NH₄NO₃ on the dust particle surface, which has been ignored and should be included in future model simulations.