The negative impact of conventional pesticides on the environment is already extensively discussed worldwide. Although the use of chemical agents for controlling agricultural pests remains as first-line strategy for pest control, novel biorational active insecticides, such as spirotetramat, have appeared in the pesticide market during recent years in Argentina. The aim of this study was to assess the toxicity of spirotetramat on two developmental stages of a Neotropical strain of Eretmocerus mundus, with the conventional insecticide cypermethrin as a positive control, and to determine spirotetramat’s side effects on parasitoid demographic parameters. Lethal effects of both insecticides on pupae and adults were evaluated by adult emergency and survival, respectively; whereas sublethal effects on both development stages were assessed by adult longevity, reproduction capacity, sex ratio, and longevity of the first progeny. Spirotetramat proved less harmful than cypermethrin at both developmental stages studied, corroborating once more the high toxicity of this pyrethroid to natural enemies. Although spirotetramat did not affect the emergence and reproductive capacity of adults surviving pupal exposure, the longevity of the first progeny was reduced as was adult survival and longevity after exposure to residues. Spirotetramat also reduced all demographic parameters in the population evaluation. This work is the first report of spirotetramat toxicity at the population level and demonstrates the need to assess the total effect of pesticides on natural enemies.

Whole-cell biosensors based on reporter genes allow detection of toxic metals in water with high selectivity and sensitivity under laboratory conditions; nevertheless, their transfer to a commercial inline water analyzer requires specific adaptation and optimization to field conditions as well as economical considerations. We focused here on both the influence of the bacterial host and the choice of the reporter gene by following the responses of global toxicity biosensors based on constitutive bacterial promoters as well as arsenite biosensors based on the arsenite-inducible Pₐᵣₛ promoter. We observed important variations of the bioluminescence emission levels in five different Escherichia coli strains harboring two different lux-based biosensors, suggesting that the best host strain has to be empirically selected for each new biosensor under construction. We also investigated the bioluminescence reporter gene system transferred into Deinococcus deserti, an environmental, desiccation- and radiation-tolerant bacterium that would reduce the manufacturing costs of bacterial biosensors for commercial water analyzers and open the field of biodetection in radioactive environments. We thus successfully obtained a cell survival biosensor and a metal biosensor able to detect a concentration as low as 100 nM of arsenite in D. deserti. We demonstrated that the arsenite biosensor resisted desiccation and remained functional after 7 days stored in air-dried D. deserti cells. We also report here the use of a new near-infrared (NIR) fluorescent reporter candidate, a bacteriophytochrome from the magnetotactic bacterium Magnetospirillum magneticum AMB-1, which showed a NIR fluorescent signal that remained optimal despite increasing sample turbidity, while in similar conditions, a drastic loss of the lux-based biosensors signal was observed.

Converting the NO from gaseous pollutant into NH₄ ⁺ through electrocatalytical reduction using cost-effective materials holds great promise for pollutant purifying and resources recycling. In this work, we developed a highly selective and stable catalyst CoSe₂ nanoparticle hybridized with carbon nanotubes (CoSe₂@CNTs). The CoSe₂@CNTs hybrid catalysts performed an extraordinary high selectivity for NH₄ ⁺ formation in NO electroreduction with minimal N₂O production and H₂ evolution. The specific spatial structure of CoSe₂ is conductive to the predominant formation of N-H bond between the N from adsorbed NO and H and inhibition of N-N formation from adjacent adsorbed NO. It was also the first time to convert the coordinated NO into NH₄ ⁺ using non-noble metal catalysis. Moreover, the original concept of employing CoSe₂ as eletrocatalyst for NO hydrogenation presented in this work can broaden horizons and provide new dimensions in the design of new highly efficient catalysts for NH₄ ⁺ synthesis in aqueous solution.

The recovery of microbial community and activities is crucial to the remediation of contaminated soils. Distance-dependent variations of microbial community composition and metabolic characteristics in the rhizospheric soil of hyperaccumulator during phytoextraction are poorly understood. A 12-month phytoextraction experiment with Sedum alfredii in a Cd-contaminated soil was conducted. A pre-stratified rhizobox was used for separating sub-layer rhizospheric (0–2, 2–4, 4–6, 6–8, 8–10 mm from the root mat)/bulk soils. Soil microbial structure and function were analyzed by phospholipid fatty acid (PLFA) and MicroResp™ methods. The concentrations of total and specified PLFA biomarkers and the utilization rates for the 14 substrates (organic carbon) in the 0–2-mm sub-layer rhizospheric soil were significantly increased, as well as decreased with the increase in the distance from the root mat. Microbial structure measured by the ratios of different groups of PLFAs such as fungal/bacterial, monounsaturated/saturated, ratios of Gram-positive to Gram-negative (GP/GN) bacterial, and cyclopropyl/monoenoic precursors and 19:0 cyclo/18:1ω7c were significantly changed in the 0–2-mm soil. The PLFA contents and substrate utilization rates were negatively correlated with pH and total, acid-soluble, and reducible fractions of Cd, while positively correlated with labile carbon. The dynamics of microbial community were likely due to root exudates and Cd uptake by S. alfredii. This study revealed the stimulations and gradient changes of rhizosphere microbial community through phytoextraction, as reduced Cd concentration, pH, and increased labile carbons are due to the microbial community responses.

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous constituents of air particulate matter and can be taken up by plants from the atmosphere. However, the purification of particulate-bound PAHs in the atmosphere by greening tree species has not been reported. In this study, we assess the concentrations, distribution, and sources of PM₂.₅-bound PAHs at three representative sites of Beijing in April, July, and November (non-heating period) and analyze the correlation between PAHs in Populus tomentosa leaves and in atmospheric PM₂.₅. The total PAH concentrations in PM₂.₅ were in the range of 19.85 ± 13.59–42.01 ± 37.17 ng/m³ with mean value of 31.35 ng/m³ at the three sites, and the PM₂.₅-bound PAHs concentrations in the two suburban sites (YF and YQ) were significantly higher than that in urban site (XZM) in November (autumn). At the three sites, the high molecular weight (HMW) PAHs in PM₂.₅ were dominant, accounting for 54.09–64.90% of total PAHs and the concentration of HMW PAHs was, on average, 9.1 times higher than that of low molecular weight (LWM) PAHs. Principal component analysis combined with diagnostic ratio analysis indicated that vehicle emission, wood combustion, and industrial processes were the main sources for PM₂.₅-bound PAHs in the non-heating period of Beijing. However, the LMW PAHs were dominant in P. tomentosa leaves. The concentrations of HMW PAHs (BbF, BkF, BaP, IcdP, and BghiP) in P. tomentosa leaves reached 26.11 ± 2.39, 41.42 ± 7.77, and 55.70 ± 12.33 ng/g at YQ, XZM, and YF in autumn, respectively, and were, on average, 2.1 times higher than those in April (spring) at the three sites. The ∑5PAHs concentration in P. tomentosa leaves accumulatively increased from spring to autumn, which was not related to the temporal variation of PM₂.₅-bound PAHs. Nevertheless, the ∑5PAHs mean concentrations followed the order of YF > XZM > YQ. This trend was consistent with spatial distribution of atmosphere PM₂.₅, indicating that HMW PAHs in leaves increased with the increase of atmosphere PM₂.₅ concentration. Our results indicated that P. tomentosa may be used as a useful species for removing PAHs from the air and biomonitoring PAHs in atmosphere.

A quasi-hexagonal prism-shaped carbon nitride (H-C₃N₄) was synthesized from urea-derived C₃N₄ (U-C₃N₄) using an alkaline hydrothermal process. U-C₃N₄ decomposition followed by hydrogen bond rearrangement of hydrolyzed products leads to the formation of a quasi-hexagonal prism-shaped structure. The H-C₃N₄ catalysts displayed superior activity in the photoreduction of CO₂ with H₂O compared to U-C₃N₄. The enhanced photocatalytic activities can be attributed to the promotion of incompletely coordinated nitrogen atom formation in the C₃N₄ molecules. Graphical abstract ᅟ

The recovery of silver from Ag⁺ solution coupled with power generation was investigated in bio-electrochemical system (BES). In this system, chemical energy existing in the organic matter in the anode chamber can be converted biologically to electrical energy which can be used for the reduction of Ag⁺ ions in the cathode chamber. Results showed that type of substrate influenced the metabolic pathway and affected the cell voltage progression, and columbic efficiency. Silver recovery was not affected by increasing initial pH (2.0 to 7.0) and Ag⁺ concentration (100 to 1000 mg/L) in the catholyte, whereas power generation was improved. A maximum power density of 8258 mW/m³ and a columbic efficiency of 21.61% could be achieved with 1000 mg/L of Ag⁺. Ag⁺ ions were reduced to form metallic deposits as Ag⁰ crystals on the cathode surface, which were then confirmed by scanning electron microscope (SEM) image and energy dispersive X-ray (EDX) spectrum. The BES reactor had high silver removal (i.e., >96%) after 24 h of operation. When considering the crossover of Ag⁺ ions through the cation exchange membrane, the removal was in the range of 83.73–92.51%. This crossover was not considerable as compared to the Ag⁺ initial concentration. At higher initial Ag⁺ concentration (2000 mg/L), the silver removal decreased to 88.61% and the maximum power density decreased to 5396 mW/m³. This study clearly showed that BES can be employed for silver recovery, wastewater treatment, and also electricity generation.

We studied adsorption of organic compounds to a wide range of indoor materials, including plastics, gypsum board, carpet, and many others, under various relative humidity conditions by applying a conceptual model of the free energy of interfacial interactions of both van der Waals and Lewis acid-base (e-donor/acceptor) types. Data used for the analyses were partitioning coefficients of adsorbates between surface and gas phase obtained from three sources: our sorption experiments and two other published studies. Target organic compounds included apolars, monopolars, and bipolars. We established correlations of partitioning coefficients of adsorbates for a considered surface with the corresponding hexadecane/air partitioning coefficients of the adsorbates which are used as representative of a van der Waals descriptor instead of vapor pressure. The logarithmic adsorption coefficients of the apolars and weak bases, e.g., aliphatics and aromatics, to indoor materials linearly correlates well with the logarithmic hexadecane/air partitioning coefficients regardless of the surface polarity. The surface polarity in terms of e-donor/acceptor interactions becomes important for adsorption of the strong bases and bipolars, e.g., amines, phenols, and alcohols, to unpainted gypsum board. Under dry or humid conditions, the adsorption to flat plastic materials still linearly correlates well with the van der Waals interactions of the adsorbates, but no correlations were observed for the adsorption to fleecy or plush materials, e.g., carpet. Adsorption of highly bipolar compounds, e.g., phenol and isopropanol, is strongly affected by humidity, attributed to Lewis acid-base interactions with modified surfaces.

Exposure to bisphenol A (BPA) is known to be widespread and available data suggests that BPA can act as an endocrine disruptor. Diet is generally regarded as the dominant BPA exposure source, namely through leaching to food from packaging materials. The aim of this study was to evaluate the exposure of 110 Portuguese children (4–18 years old), divided in two groups: the regular diet group (n = 43) comprised healthy normal weight/underweight children with no dietary control; the healthy diet group (n = 67) comprised children diagnosed for obesity/overweight (without other known associated diseases) that were set on a healthy diet for weight control. First morning urine samples were collected and total urinary BPA was analyzed after enzymatic hydrolysis via on-line HPLC-MS/MS with isotope dilution quantification. Virtually, all the children were exposed to BPA, with 91% of the samples above the LOQ (limit of quantification) of 0.1 μg/L. The median (95th percentile) urinary BPA levels for non-normalized and creatinine-corrected values were 1.89 μg/L (16.0) and 1.92 μg/g creatinine (14.4), respectively. BPA levels in the regular diet group were higher than in the healthy diet group, but differences were not significant. Calculated daily BPA intakes, however, were significantly higher in children of the regular diet group than in children of healthy diet group. Median (95th percentile) daily intakes amounted to 41.6 (467) ng/kg body weight/day in the regular diet group, and 23.2 (197) ng/kg body weight/day in the healthy diet group. Multiple logistic regression analysis revealed that children in the healthy diet group had 33% lower intakes than children in the regular diet group (OR 0.67; 95% CI 0.51–0.89). For both groups, however, urinary BPA levels and daily BPA intakes were within the range reported for other children’s populations and were well below health guidance values such as the European Food Safety Authority (EFSA) temporary tolerable daily intake (t-TDI) of 4 μg/kg body weight/day. In addition, lower daily BPA intakes were more likely linked with the inherent dietary approach rather than with high BMI or obesity.

Under greenhouse conditions, we evaluated establishment of four tree species and their capacity to degrade crude oil recently incorporated into the soil; the species were as follows: Cedrela odorata (tropical cedar), Haematoxylum campechianum (tinto bush), Swietenia macrophylla (mahogany), and Tabebuia rosea (macuilis). Three-month-old plants were planted in soil with three treatments of heavy petroleum and a control (C0 0 mg kg⁻¹; C1 18,000 mg kg⁻¹; C2 31,700 mg kg⁻¹; C3 47,100 mg kg⁻¹) with four repetitions per treatment and species; the experiment was carried out for 245 days. Height and biomass of all species significantly diminished as petroleum concentration increased, although plant survival was not affected. The quantity of colony-forming units (CFU) of rhizospheric bacteria varied among tree species and treatments; petroleum stimulated bacterial CFU for S. macrophylla. The number of fungi CFU for S. macrophylla and T. rosea was significantly greater in C0 than in soil with petroleum, but among species and among different concentrations, no significant differences were found. The greatest percentage of total petroleum hydrocarbon (TPH) degradation was found in C1 for soil without plants (45 %). Differences from the remaining treatments (petroleum concentrations in soil and plant species) were not significant (P < 0.05). Among all trees, H. campechianum had the greatest TPH degradation (32.5 % in C2). T. rosea (C1) and H. campechianum (C2) resulted in petroleum degradation at levels ranging from 20.5 to 32.5 %. On the basis of this experiment, the tree species used did not improve TPH degradation. However, all of them showed high rates of survival and vigor. So, as tree species provide goods and services, experiments with inoculation of hydrocarbonclastic microorganisms, addition of fertilizers, and mixture of tree and grasses are recommended.