Most of the detrimental effects of using conventional insecticides to control crop pests are now well identified and are nowadays major arguments for replacing such compounds by the use of biological control agents. In this respect, the bacterium Bacillus thuringiensis var. kurstaki and Trichogramma (Hymenoptera: Trichogrammatidae) parasitic wasp species are both effective against lepidopterous pests and can actually be used concomitantly. In this work, we studied the potential side effects of B. thuringiensis var. kurstaki on Trichogramma chilonis females. We first evidenced an acute toxicity of B. thuringiensis on T. chilonis. Then, after ingestion of B. thuringiensis at sublethal doses, we focused on life history traits of T. chilonis such as longevity, reproductive success and the time spent on host eggs patches. The reproductive success of T. chilonis was not modified by B. thuringiensis while a significant effect was observed on longevity and the time spent on host eggs patches. The physiological and ecological meanings of the results obtained are discussed.

Commercial production of nanoparticles (NP) has created a need for research to support regulation of nanotechnology. In the current study, microbial biofilm communities were developed in rotating annular reactors during continuous exposure to 500 μg L⁻¹ of each nanomaterial and subjected to multimetric analyses. Scanning transmission X-ray spectromicroscopy (STXM) was used to detect and estimate the presence of the carbon nanomaterials in the biofilm communities. Microscopy observations indicated that the communities were visibly different in appearance with changes in abundance of filamentous cyanobacteria in particular. Microscale analyses indicated that fullerene (C60) did not significantly (p < 0.05) impact algal, cyanobacterial or bacterial biomass. In contrast, MWCNT exposure resulted in a significant decline in algal and bacteria biomass. Interestingly, the presence of SWCNT products increased algal biomass, significantly in the case of SWCNT-COOH (p < 0.05) but had no significant impact on cyanobacterial or bacterial biomass. Thymidine incorporation indicated that bacterial production was significantly reduced (p < 0.05) by all nanomaterials with the exception of fullerene. Biolog assessment of carbon utilization revealed few significant effects with the exception of the utilization of carboxylic acids. PCA and ANOSIM analyses of denaturing gradient gel electrophoresis (DGGE) results indicated that the bacterial communities exposed to fullerene were not different from the control, the MWCNT and SWNT-OH differed from the control but not each other, whereas the SWCNT and SWCNT-COOH both differed from all other treatments and were significantly different from the control (p < 0.05). Fluorescent lectin binding analyses also indicated significant (p < 0.05) changes in the nature and quantities of exopolymer consistent with changes in microbial community structure during exposure to all nanomaterials. Enumeration of protozoan grazers showed declines in communities exposed to fullerene or MWCNT but a trend for increases in all SWCNT exposures. Observations indicated that at 500 μg L⁻¹, carbon nanomaterials significantly alter aspects of microbial community structure and function supporting the need for further evaluation of their effects in aquatic habitats.

One technique applied to restore degraded or contaminated soils is to use amendments made of different types of waste materials, which in turn may contain metals such as Cu, Pb and Zn. For this reason, it is important to determine the capacity of the soil to retain these materials, and to compare the sorption capacity between an amended soil and another unamended soil. The aim of this study was to determine the mobility and availability of these metals in the soil after applying the amendment, and how it affected the soil’s sorption capacity. Sorption isotherms were compared with the empirical models of Langmuir and Freundlich to estimate the sorption capacity. The overall capacity of the soils to sorb Cu, Pb or Zn was evaluated as the slope Kr. The amendments used in this study were a mixture made of compost and biochar in different proportions (20, 40, 60, 100 %), which were applied to the mine tailing from a settling pond from a copper mine. The mine tailing that were amended with the mixture of compost and biochar had a higher sorption capacity than the mine tailing from the unamended pond, and their sorption isotherms had a greater affinity towards Cu, Pb and Zn than the mine tailing that was studied. Therefore, the results obtained show that adding a mixture of compost and biochar favours the retention of Cu, Pb and Zn in mine tailing.

This study aimed to contribute to the enhancement of the knowledge of levels, trends and behaviour of eight siloxanes (four linear and four cyclic) in the environment. Adding to the prioritised scrutiny of the incidence in the atmosphere through passive samplers (sorbent-impregnated polyurethane foam disks—SIPs), the sampling of pine needles and soil was also performed, thus closing the circle of atmospheric exposure in the areas of study. Two sampling campaigns (one in summer and one in winter) were done in a total of eight sampling points in the Portuguese territory, which covered a wide range of human presence and land uses (urban, industrial, remote and beach areas). By adopting a “green” approach in terms of analytical methods, namely reducing the clean-up steps for the passive air samples and using the quick, easy, cheap, effective, rugged and safe (QuEChERS) technology for soils and pine needles, the results showed total concentration of siloxanes between 5 and 70 ng g⁻¹ (dry weight) for soils and from 2 to 118 ng g⁻¹ (dry weight (dw)) for pine needles, with no clear seasonal trend. For SIPs, the levels varied from 0.6 to 7.8 ng m⁻³ and were higher in summer than in winter in all sites. Overall, the cyclic siloxanes were found in much higher concentrations, with D5 and D6 being the most predominant in a great majority of cases. Also, the urban and industrial areas had the highest incidence, suggesting a strong anthropogenic fingerprint, in line with their main uses.

Prevention of chemical transfer from soil to surface runoff, under condition of irrigation and subsurface drainage, would improve surface water quality. In this paper, a series of laboratory experiments were conducted to assess the effects of various soil and hydraulic factors on chemical transfer from soil to surface runoff. The factors include maximum depth of ponding water on soil surface, initial volumetric water content of soil, depth of soil with low porosity, type or texture of soil and condition of drainage. In the experiments, two soils, sand and loam, mixed with different quantities of soluble KCl were filled in the sandboxes and prepared under different initial saturated conditions. Simulated rainfall induced surface runoff are operated in the soils, and various ponding water depths on soil surface are simulated. Flow rates and KCl concentration of surface runoff are measured during the experiments. The following conclusions are made from the study results: (1) KCl concentration in surface runoff water would decrease with the increase of the maximum depth of ponding water on soil surface; (2) KCl concentration in surface runoff water would increase with the increase of initial volumetric water content in the soil; (3) smaller depth of soil with less porosity or deeper depth of soil with larger porosity leads to less KCl transfer to surface runoff; (4) the soil with finer texture, such as loam, could keep more fertilizer in soil, which will result in more KCl concentration in surface runoff; and (5) good subsurface drainage condition will increase the infiltration and drainage rates during rainfall event and will decrease KCl concentration in surface runoff. Therefore, it is necessary to reuse drained fertile water effectively during rainfall, without polluting groundwater. These study results should be considered in agriculture management to reduce soluble chemical transfer from soil to surface runoff for reducing non-point sources pollution.

Cadmium (Cd) in agricultural soil negatively affects crops yield and compromises food safety. Remediation of polluted soil is necessary for the re-establishment of sustainable agriculture and to prevent hazards to human health and environmental pollution. Phytoremediation is a promising technology for decontamination of polluted soil. The present study investigated the effect of molybdenum (Mo) (0.5, 1.0 and 2.0 ppm) on endogenous production of total phenolics and free proline, plant biomass and photosynthetic pigments in Ricinus communis plants grown in Cd (25, 50 and 100 ppm) contaminated soils and the potential for Cd phytoextraction. Mo was applied via seed soaking, soil addition and foliar spray. Foliar sprays significantly increased plant biomass, Cd accumulation and bioconcentration. Phenolic concentrations showed significantly positive correlations with Cd accumulation in roots (R ² = 0.793, 0.807 and 0.739) and leaves (R ² = 0.707, 721 and 0.866). Similarly, proline was significantly positively correlated with Cd accumulation in roots (R ² = 0.668, 0.694 and 0.673) and leaves (R ² = 0.831, 0.964 and 0.930). Foliar application was found to be the most effective way to deliver Mo in terms of increase in plant growth, Cd accumulation and production of phenolics and proline.

The evaluation of formaldehyde (FD) exposure in beauty salons, due to the use of hair straightening products, and its relation with genotoxicity biomarkers was performed in this study. Regardless of official recommendations, the inappropriate use of homemade hair creams has became a popular practice in Brazil, and high formaldehyde content in the “progressive straightening” creams can contain mutagens that could increase the incidence of neoplasia in those people who use them. Damage to DNA was assessed by conducting a micronuclei test (MNT) on buccal cells and the comet assay on heparinized venous blood samples. A total of 50 volunteers were recruited at six different beauty salons (labeled A to F). At two salons that used products that did not contain FD (salons D and E), environmental FD concentrations were 0.04 and 0.02 ppm. In contrast, the products used at salons A, B, C, and F contained 5.7, 2.61, 5.9, and 5.79 % of FD, and these salons had environmental FD concentrations of 0.07, 0.14, 0.16, and 0.14 ppm, respectively. Comparison of the beauty salon workers from each of the six beauty salons revealed significant differences in urinary formic acid (FA) concentration before exposure (p = 0.016), urinary FA after exposure (p = 0.004), variation in FA concentration before and after exposure (p = 0.018), environmental FD concentration (p < 0.001), cytogenetic damage detected by the comet assay according to both damage index (p < 0.001) and frequency of damage (p < 0.001), and for karyorrhexis only according to the MNT (p = 0.001).

With the rapid development of urbanization and industrialization, many developing countries are suffering from heavy air pollution. Governments and citizens have expressed increasing concern regarding air pollution because it affects human health and sustainable development worldwide. Current air quality prediction methods mainly use shallow models; however, these methods produce unsatisfactory results, which inspired us to investigate methods of predicting air quality based on deep architecture models. In this paper, a novel spatiotemporal deep learning (STDL)-based air quality prediction method that inherently considers spatial and temporal correlations is proposed. A stacked autoencoder (SAE) model is used to extract inherent air quality features, and it is trained in a greedy layer-wise manner. Compared with traditional time series prediction models, our model can predict the air quality of all stations simultaneously and shows the temporal stability in all seasons. Moreover, a comparison with the spatiotemporal artificial neural network (STANN), auto regression moving average (ARMA), and support vector regression (SVR) models demonstrates that the proposed method of performing air quality predictions has a superior performance.

Nitrate is a worldwide pollutant in aquifers. Shallow aquifer nitrate concentrations generally display vertical stratification, with a maximum concentration immediately below the water level. The concentration then gradually decreases with depth. Different techniques can be used to highlight this stratification. The paper aims at comparing the advantages and limitations of three open hole multilevel sampling techniques (packer system, dialysis membrane samplers and bailer), chosen on the base of a literary review, to highlight a nitrate vertical stratification under the assumption of (sub)horizontal flow in the aquifer. The sampling systems were employed at three different times of the year in a shallow aquifer piezometer in northern Italy. The optimal purge time, equilibration time and water volume losses during the time in the piezometer were evaluated. Multilevel techniques highlighted a similar vertical nitrate stratification, present throughout the year. Indeed, nitrate concentrations generally decreased with depth downwards, but with significantly different levels in the sampling campaigns. Moreover, the sampling techniques produced different degrees of accuracy. More specifically, the dialysis membrane samplers provided the most accurate hydrochemical profile of the shallow aquifer and they appear to be necessary when the objective is to detect the discontinuities in the nitrate profile. Bailer and packer system showed the same nitrate profile with little differences of concentration. However, the bailer resulted much more easier to use.

Salicylic acid (SA) mediates tolerance mechanisms in plants against a wide spectrum of biotic and abiotic stresses. Therefore, the present study was carried out to determine how SA regulates the plant protection mechanisms in two cultivars of oilseed rape (Brassica napus L.) under chromium (Cr) stress. Exogenously applied SA enhanced plant growth, increased dry biomasses, and strengthened the reactive oxygen scavenging system by improving cell organelles that were severely damaged via Cr toxicity. The contents of Cr were significantly enhanced in both root and leaf of cultivar Zheda 622 (yellow color) compared with cultivar ZS 758 (black color). Exogenous application of SA significantly reduced the Cr contents in both plant organs as well as enhanced the SA contents under Cr stress. A dose-dependent increase was observed in reactive oxygen species (ROS) generation under Cr stress. To ease the inimical effects of ROS, plants’ defense systems were induced under Cr stress, and SA further enhanced protection. Further, TEM micrographs results showed that Cr stress alone significantly ruptured the plant cell organelles of both cultivars by increasing the size of starch grain and the number of plastoglobuli, damaging the chloroplast and mitochondrion structures. However, exogenously applied SA significantly recovered these damages in the plant cells of both cultivars. It was also observed that cultivar ZS 758 was proved to be more tolerant under Cr toxicity. Gene expression analysis revealed that combined treatments of Cr and SA increased antioxidant-related gene expression in both cultivars. Findings of the present study demonstrate that SA induces the enzymatic antioxidant activities and related gene expression, secondary metabolism, and improves the cell structural changes and the transcript level of specific stress-associated proteins in root and leaf of two oilseed rape cultivars under Cr toxicity.