Cadmium (Cd) is among the non-essential elements for the growth of crops while silicon (Si) is a beneficial element for plant growth. There is little evidence regarding the use of silicon nanoparticles (Si NPs) on the reduction of Cd accumulation in crops especially wheat. The present study determined the impact of seed priming with Si NPs on Cd-induced responses in wheat in terms of growth, yield, photosynthesis, oxidative stress, and Si and Cd accumulation in wheat. Seed priming was done by different levels of Si NPs (0, 300, 600, 900, 1200 mg/L) for 24 h by providing continuous aeration. Afterwards, seeds were sown in soil contaminated with Cd. The results depicted that Si NPs positively affected the wheat growth and chlorophyll contents over the control. The Si NPs diminished the oxidative stress and positively affected the antioxidant enzyme activity. The Si NPs decreased the Cd concentrations in wheat, especially in grains, and increased the Si concentrations in plants. The Si NPs reduced the Cd contents by 10–52% in shoot, by 11–60% in roots, and by 12–75% in grains as compared with respective controls. The study suggested that the use of Si NPs may be a tool for reducing the Cd toxicity in wheat and declining its concentration in grains. Thus, Si NPs application by seed priming method might be helpful in increasing plants biomass and yield while reducing the oxidative stress and Cd uptake in wheat grains.

The removal of 17β-estradiol (E2) from contaminated water on nanoscale Fe–Mn binary oxide-loaded multiwalled carbon nanotubes (MWCNTs/FMBO) was evaluated in this work. The characterizations of the mesoporous adsorbent were analyzed by using SEM, TEM, VSM, XRD, XPS, and FTIR measurements. The effects of experimental conditions in E2 removal, including stabilizer additional level, adsorption time, initial E2 concentration, solution pH, reaction temperature, and foreign ions, were examined. The maximum monolayer adsorption capacity (qₘ) of MWCNTs/FMBO for E2 in the experiment was 47.25 mg/g as verified by the Langmuir sorption isotherm study. The adsorption process was pH-sensitive with an optimum pH of 7.0. On the kinetics study, the adsorption data could be satisfactorily fitted by the pseudo-second-order kinetics. Thermodynamic parameters indicated that the adsorption process was spontaneous and exothermal. In addition, the foreign ions did not show any noticeable inhibition for E2 removal from the water solution except for PO₄³⁻ that was adversely affected for E2 uptake than other anions in a certain concentration. The adsorption capacities of the mesoporous adsorbent remained at 86.16% even after five adsorption–desorption cycles without significant loss of capacity, which demonstrated the stability and reusability for further removal of E2. Moreover, both hydrogen bond and π–π interaction might be the dominating adsorption mechanisms for E2 adsorption onto MWCNTs/FMBO.

The aim of this study was to examine the effect of the secondary biological treatment plant effluent administration on the kidneys, urinary bladder, and testis of Wistar rats in relation to lead (Pb) and cadmium (Cd) accumulation, since such an effluent is used for irrigation of edible plants. Male Wistar rats, randomly assigned into 5 groups, were treated with domestic sewage effluent (DSE) for 24 months. Cadmium and lead concentrations in the DSE, rats’ tissues, and urine were estimated by means of atomic spectroscopy. Lead was rapidly accumulated in high amounts in rats’ kidney and to a lesser extent in the testis whereas Cd concentration was raised in all tissues examined. Deposition of Cd and Pd in the kidney of the rats resulted in profound damage over time. The results showed that long-term administration to DSE as drinking water exposes living organisms to urogenital stress related to heavy metal concentration and pH of the effluent.

Daphniopsis tibetana Sars lives in elevation, usually with strong solar UV radiation. We speculate that UV may have an effect on the ecology and evolutionary biology of this species. However, the regulatory effect and mechanism of UV on D. tibetana have not been studied previously. Here, our results showed that UVB could act as a positive factor in the relative body lengths, reproductive parameters, and population growth parameters of D. tibetana when UVB radiation is 20–170 mJ cm⁻², compared with the control group. Strikingly, these parameters were highest at 120 mJ cm⁻². To explore the mechanism underlying the UVB irradiation effects, we conducted a transcriptome analysis using the Trinity platform. The results indicated that differentially regulated genes were mostly enriched in lipid transport and lipid localization by Gene Ontology (GO) enrichment analysis of 146 differentially expressed genes (83 upregulated and 63 downregulated). This is the first study of UVB radiation of D. tibetana to reveal genes that may have crucial roles in survival, growth, and reproduction and could be candidates for future functional studies. Additionally, the study could supply a substantial resource for investigating and elucidating lipids that could play important roles in a physiological context.

Waste electric and electronic equipment (WEEE) represents a potential secondary source of valuable materials, whose recovery is a growing business activity worldwide. In low-income countries, recycling is carried out under poorly controlled conditions resulting in severe environmental pollution. High concentrations of both metallic and organic pollutants have been confirmed in air, soil, water, and sediments in countries with informal recycling areas. The release of these contaminants into the environment presents a risk to the health of the exposed population that has been widely acknowledged but still needs to be quantified. The aim of this work was to evaluate the relative risk from inhalation associated with the open burning of different kinds of WEEE. The shrinking core model was applied to estimate the concentration of the metals which would be released into the environment during the incineration of different types of WEEE. In addition, the potential generation of dioxins during the same informal practice was estimated, based on the plastic content of the WEEE. The results provided for the first time a comparative analysis of the risk posed from the open burning of WEEE components, proposing a methodology to address the absolute risk assessment to workers from the informal recycling of WEEE.

Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants. Exposure to PAHs is associated with several adverse health outcomes. However, no previous study has examined the relationship between PAH exposure and functional dependence in an elderly population. Our aim was to examine whether PAH exposure was associated with functional dependence including total disability, activities of daily living (ADL), instrumental activities of daily living (IADL), leisure and social activities (LSA), lower extremity mobility (LEM), and general physical activities (GPA) in an elderly population. A total of 5816 elderly adults from the National Health and Nutrition Examination Survey (NHANES) from 2001 to 2006 were examined. PAH exposure was measured by urinary biomarkers. Functional dependence was assessed by 19 structured questions. The association between PAH exposures with functional dependence was performed by using a multivariable linear regression model. After adjusting for pertinent variables, positive associations were observed between the total number of disabilities and 2-naphthalene and 1-pyrene quartiles (all Pₜᵣₑₙd < 0.05). There was a dose-dependent relationship between 1-pyrene quartiles and all functional dependence domains, and the higher quartile of 1-pyrene was more closely associated with functional impairment (all Pₜᵣₑₙd < 0.05). PAH exposure is associated with functional dependence in American elderly adults. Future research is needed to bring to light the pathophysiological underlying mechanisms related to these findings.

Disinfection byproducts (DBPs) in swimming pool have elicited increasing worldwide concern due to their potential health risks. However, only trihalomethanes (THMs) are regulated by several local governing bodies. Studies indicated that specific unregulated DBP classes would drive disinfected water toxicity in addition to THMs. Halobenzoquinones (HBQs), a type of emerging unregulated DBPs, have been shown to be possible bladder cancer carcinogens. This study aimed to determine the distribution and formation of HBQs in indoor and outdoor swimming pool waters of Nanning City, Southwest China. Seven HBQs in water from seven public indoor and outdoor swimming pools were examined using an effective ultra-performance liquid chromatography–tandem mass spectrometry method. Results suggest the presence of 2,6-dichloro-1,4-benzoquinone in all the swimming pool waters in the range of 4.56–45.30 ng/L. Furthermore, 2,6-dibromo-1,4-benzoquinone and 3,4,5,6-tetrachloro-1,2-benzoquinone (TetraC-1,2-BQ) were detected in two pools at concentrations of < 0.38–14.20 and < 0.54–2.60 ng/L, respectively. The swimming pool water featured higher HBQs than input tap water, and TetraC-1,2-BQ was only detected in pool water. Higher HBQ levels were observed in the indoor pools than in the outdoor pools. These findings demonstrate that low NH₃–N, high chloride, humic acid, chemical oxygen demand, and UV₂₅₄ in the indoor pools increased the HBQ formation. This study is the first to reveal the occurrence and formation of HBQs in water from Chinese indoor and outdoor swimming pools. The findings should be useful in the management of these governing factors and HBQ controls in swimming pools.

In this study, the quality of groundwater was tested in 95 sampling wells in Shuangliao City. Based on the results, the coefficient of variation method was used to calculate the comprehensively evaluated value F, and the grade of groundwater quality, in accordance with the actual scenario in the study area, was classified according to the results of the evaluation. The spatial distribution of groundwater quality types in the study area was classified. In addition, the influence of human activity on each groundwater subsystem was assessed. Combined with the land use types in the study area, the Circle model was used to extract the land use types in the circular buffer zone with a radius of 500 m, and the Kendall rank correlation test was used to analyze the influence of the land use types on the spatial distribution of groundwater pollution. Based on the coefficient of variation, the groundwater quality standard was divided into four sections considering the actual scenario: ≤ 0.92 (I), 0.92~≤ 1.75 (II), 1.75~≤ 2.40 (III), and > 2.40 (IV). Water from class II was considered the main type for groundwater quality. NO₃⁻, TFe, and Mn were deemed the main indexes of groundwater pollution. Further, land use type was found to have a great influence on the spatial distribution of groundwater pollution; specifically, dry land, paddy field, areas with dense traffic, and residential areas are the main land types that affect the groundwater environment.

The study was initiated to evaluate constructed wetland technology as a method for treating alkaline (pH 8.0–8.6) drainage high in Al, Mo, V, As and Ga originating from bauxite residue storage areas. Pilot-scale horizontal flow constructed wetlands were operated over a 40-week period using three filter materials (granitic gravel, bauxite and alum water treatment sludge), and half of the wetlands were planted with Phragmites australis and the other half left unplanted. Gravel was the least effective medium for removing the target elements, while of the two active media, water treatment sludge was more effective than bauxite. Plants removed only small amounts of elements into their above- and below-ground dry matter (0.4–4.9% of that added). Nonetheless, the presence of plants greatly increased the effectiveness of all three media since their presence decreased effluent pH values by 0.5–1.3 pH units and that of the filter media by 0.4 pH units. Removal of elements followed the order Al > Ga > V > As > Mo. For planted wetlands, total elemental removal ranged from 18 to 98% for gravel, 80 to 99% for bauxite, and 93 to 99% for water treatment sludge. The lowest removal was for Mo (ranging from 18% for gravel to 93% for water treatment sludge) and the highest for Al (ranging from 98% in gravel to 99% in water treatment sludge). A sequential fractionation scheme for As, V and Mo on filter material at the end of the experiment showed that for bauxite and water treatment sludge, V and As were concentrated in the NaOH extractable fraction while Mo was concentrated in the less strongly adsorbed NaHCO₃ extractable fraction. It was concluded that a constructed wetland with water treatment sludge as an active filter material is an effective technology for removal of the target elements from the alkali drainage.