Concerns have been raised regarding the ecotoxicity of ionic liquids (ILs) owing to their wide usage in numerous fields. Three imidazolium chloride ILs with different numbers of methyl substituents, 1-decyl-imidazolium chloride ([C10IM]Cl), 1-decyl-3-methylimidazolium chloride ([C10MIM]Cl), and 1-decyl-2,3-dimethylimidazolium chloride ([C10DMIM]Cl), were examined to assess their effects on growth, photosynthesis pigments content, chlorophyll fluorescence, photosynthetic and respiration rate, and cellular ultrastructure of Scenedesmus obliquus. The results showed that algal growth was significantly inhibited by ILs treatments. The observed IC50,48h doses were 0.10 mg/L [C10IM]Cl, 0.01 mg/L [C10MIM]Cl, and 0.02 mg/L [C10DMIM]Cl. The chlorophyll a, chlorophyll b, and total chlorophyll content declined, and the chlorophyll fluorescence parameters, minimal fluorescence yield (F0), maximal fluorescence yield (Fm), maximum quantum yield of PSII photochemistry (Fv/Fm), effective quantum yield of PSII [Y(II)], non-photochemical quenching (NPQ) and non-photosynthetic losses yield [Y(NO)] were notably affected by ILs in a dose-dependent manner. ILs affected the primary photosynthetic reaction, impaired heat dissipation capability, and diminished photosynthetic efficiency, indicating negative effects on photosystem II. The photosynthetic and respiration rates of algal cells were also reduced due to the ILs treatments. The adverse effects of ILs on plasmolysis and chloroplast deformation were examined using ultrastructural analyses; chloroplast swelling and lamellar structure almost disappeared after the [C10MIM]Cl treatment, and an increased number of starch grains and vacuoles was observed after all ILs treatments. The results indicated that one-methyl-substituted ILs were more toxic than non-methyl-substituted ILs, which were also more toxic than di-methyl-substituted ILs. The toxicity of the examined ILs showed the following order: [C10IM]Cl < [C10DMIM]Cl ≤ [C10MIM]Cl.

While infants are developing, they are easily affected by toxic chemicals existing in their environments, such as semi-volatile organic compounds (SVOCs): phthalates, polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs), and organophosphate esters (OPEs). However, the specific living environment of infants, including increased plastic products and foam floor mats, may increase the presence of these chemicals. In this study, 68 air, dust, and window film samples were collected from homes, with 3- to 6-month-old infant occupants, to analyze phthalates, PAHs, PBDEs, and OPEs. High detection rates and concentrations suggest that these SVOCs are widespread in infant environments and are associated with cooking methods, smoking habits, the period of time after decoration, and room floors. The partitioning behavior of SVOCs indicates that the logarithms of the dust/gas-phase air partition coefficient (logKD) and the window film/gas-phase air partition coefficient (logKF) in homes are not at an equilibrium state when the logarithm of the octanol/air partition coefficient (logKOA) is less than 8 or greater than 11. Considering the 3 exposure routes, ingestion and dermal absorption have become the main routes of infant exposure to phthalates and OPEs, and ingestion and inhalation have become the dominant routes of exposure to PAHs and PBDEs. The total carcinogenic risk of SVOCs, which have carcinogenic toxicities, via ingestion and dermal absorption for infants in homes exceeds the acceptable value, suggesting that the current levels of these SVOCs in homes might pose a risk to infant health.

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.

Eutrophication of lakes has become one of the world's most serious environmental problems, resulting in an urgent need to monitor and provide safeguards to control water quality. Results from analysis of lake trophic status based on calculated throphic state index (TSI) showed that 69.5% of the surveyed 277 lakes were in a state of eutrophication. Significant logarithmic relationships between light absorption of optically active components (aOACs) and TSI (R2 = 0.78) existed: TSI = 13.64 × ln(aOACs)+43.24, and the regression relationship between aOACs and TSI had a better degree of fit (R2) than the currently used reflectance-TSI relationship. aOACs appeared to be a good predictor of TSI estimation in lake ecosystems. The relationship coefficient (aOACs-TSI) slightly varied with lake type, and relationships in saline lakes and phy-type lakes were shown to be more robust than the relationship with the total lake data. This study highlights the quantification of the trophic status in lakes using aOACs, which realized the monitoring of trophic status in lakes using inherent optical properties on a large-scale. To our knowledge this is the first investigation to assess the variability of trophic status in lakes across China. The assessment trophic state of lakes based on aOACs provides a new way to monitor the trophic status of lakes, and findings may have applications for monitoring large-scale and long-term trophic patterns in lakes using remote sensing techniques.

Using a realistic and environmental relevant approach, the present study aimed at understanding the biochemical and physiological basis of glyphosate (GLY)-induced stress in non-target plant species, using tomato (Solanum lycopersicum L.) as a model. For this purpose, plants were grown for 28 days under different concentrations of a commercial formulation of GLY (Roundup® UltraMax) - 0, 10, 20 and 30 mg kg⁻¹ soil. The exposure of plants to increasing concentrations of GLY caused a severe inhibition of growth (root and shoot elongation and fresh weight), especially in the highest treatments. In what regards the levels of reactive oxygen species (ROS), both hydrogen peroxide (H₂O₂) and superoxide anion (O₂.⁻) remained unchanged in shoots, but significantly increased in roots. Moreover, a concentration-dependent decrease in lipid peroxidation (LP) was found in shoots, though in roots differences were only found for the highest concentration of GLY. The evaluation of the antioxidant system showed that GLY interfered with several antioxidant metabolites (proline, ascorbate and glutathione) and enzyme activities (superoxide dismutase – SOD; catalase – CAT; ascorbate peroxidase – APX), generally inducing a positive response of the defense mechanisms. Overall, data obtained in this study unequivocally demonstrated that soil contamination by GLY, applied as part of its commercial formulation Roundup® UltraMax, impairs the growth and physiological performance of tomato plants, and likely of other non-target plant species, after 28 days of exposure by clearly affecting the normal redox homeostasis.

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.

It remains a challenge to precisely predict and control environmental behaviors of ionizable organic contaminants (IOCs) due to their species change relative to pH and because of the lack of appropriate models to illustrate the underlying pH-dependent mechanisms. We studied the pH-dependent sorption behavior of five sulfonamide antibiotics (SAs) as typical IOCs with different pKₐ values towards a series of biochars as representative sorbents with well-characterized surface structures. After subtracting the contribution of the speciation effect using a classical speciation model, up to three unexpected enhanced sorption peaks could be found and regulated by the pKₐ,SA of the SAs and the pKₐ, BC of the biochars. The mono H-bond formation between the two pKₐ,SA of the SAs (pKₐ,SA₁ is from NH₂, pKₐ,SA₂ is from SO₂NH), and the biochar surface functional groups with comparable pKₐ values generated two peaks. Another peak around the middle between pKₐ,SA₁ and pKₐ,SA₂ appeared due to the aromatic π bonding-enhanced dual H-bond. All of these peaks were quantitatively separated by a novel two-compartment model, which was developed by capturing the characteristics of pH-dependent sorption. The quantified hydrogen bonding among different SAs elucidates the effectiveness and limits of the pKₐ equalization principle to predict the strengthening of hydrogen bonding at the solid-aqueous interface. This work recognizes the quantitative relationship among the structure, sorption, and H-bond interaction of biochars and guides the prediction of the fate of IOCs in the environment and the development of remediation options.

Chronic ambient fine particulate matter (PM₂.₅) exposure correlates with various adverse health outcomes. Its impact on the circulating metabolome−a comprehensive functional readout of the interaction between an organism's genome and environment−has not however been fully understood. This study thus performed metabolomics analyses using a chronic PM₂.₅ exposure mouse model. C57Bl/6J mice (female) were subjected to inhalational concentrated ambient PM₂.₅ (CAP) or filtered air (FA) exposure for 10 months. Their sera were then analyzed by liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS). These analyses identified 2570 metabolites in total, and 148 of them were significantly different between FA- and CAP-exposed mice. The orthogonal partial least-squares discriminant analysis (OPLS-DA) and heatmap analyses displayed evident clustering of FA- and CAP-exposed samples. Pathway analyses identified 6 perturbed metabolic pathways related to amino acid metabolism. In contrast, biological characterization revealed that 71 differential metabolites were related to lipid metabolism. Furthermore, our results showed that CAP exposure increased stress hormone metabolites, 18-oxocortisol and 5a-tetrahydrocortisol, and altered the levels of circadian rhythm biomarkers including melatonin, retinal and 5-methoxytryptophol.

Ionic liquids (ILs) are extensively used in several chemistry fields. And research about the effects of ILs on soil microbes is needed. In this study, brown soil was exposed to 1-butyl-3-methylimidazolium bromide ([C₄mim]Br), 1-hexyl-3-methylimidazolium bromide ([C₆mim]Br) and 1-decyl-3-methylimidazolium bromide ([C₁₀mim]Br). The toxicities of the three ILs are evaluated by measuring the soil culturable microbial number, enzyme activity, microbial diversity and, abundance of the ammonia monooxygenase (amoA) genes of ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). Results showed that all tested ILs caused a decrease in culturable microbial abundance. Tested ILs exposure inhibit urease activity and promote acid phosphatase and β-glucosidase activities. Tested ILs reduced soil microbial diversity and the abundances of AOB-amoA and AOA-amoA genes significantly. After a comparison of the integrated biomarker response (IBR) index, the toxicities of tested ILs to soil microorganisms were as follows: [C₁₀mim]Br > [C₆mim]Br > [C₄mim]Br. Among all collected biomarkers, the abundance of the AOA-amoA gene was the most sensitive one and was easily affected after ILs exposure.

Hydrotalcite (HT) is a layered double hydroxide (LDH), which is considered as a potential adsorbent to remove anion contaminants. In this study, adsorption of chromate (CrO₄) and phosphate (PO₄) on HT was conducted at various pH and temperatures. Related adsorption mechanisms were determined via the isotherm, kinetic, and competitive adsorption studies as well as the Cr K-edge X-ray absorption fine-structure (XAFS) spectroscopy. The maximum adsorption capacities for CrO₄ and PO₄ on HT were 0.16 and 0.23 mmol g⁻¹. Regarding adsorption kinetics, CrO₄ and PO₄ adsorption on HT could be well described by the second order model, and the rate coefficient of CrO₄ and PO₄ on HT decreased significantly with the increasing pH from 5 to 9. The adsorption kinetics for CrO₄ and PO₄ were divided into fast and slow stages with the boundary at 15 min. This biphasic adsorption behavior might be partially attributed to multiple reactive pathways including anion exchange and surface complexation. Fitting results of Cr K-edge EXAFS analysis showed a direct bonding between CrO₄ and Al on HT surfaces. Such a surface complexation appeared to be the rate-limiting step for CrO₄ adsorption on HT. By contrast, the diffusion through the hydrated interlayer space of HT was the major rate-limiting step for PO₄. This study determined the adsorption behaviors of CrO₄ and PO₄ on HT, including the initial transfer process and the subsequent adsorption mechanisms. Such information could improve the strategy to use HT as the potential adsorbent for the remediation of anionic pollutants.