Chromium is used in daily life and has a wide range of functions. It plays an important role in protein synthesis and carbohydrate and lipid metabolism. Chromium is found in trivalent Cr(III) and hexavalent Cr(VI) form; Cr(III) is relatively stable and intimately participates with many phenomena of metabolisms. Whereas, Cr(VI) is toxic, which results in growth inhibition and leading to changes in components of antioxidant systems as well as secondary metabolites. However, the molecular mechanism that is involved in Cr (VI)-induced hepatotoxicity is still unclear. For this purpose, 40 chickens were randomly assigned into two groups: the normal group (feeding the basic diet and clear water), the chromium group (16%LD₅₀, 74.24 mg/kg/day K₂Cr₂O₇). The samples were subjected to pathological examination and UHPLC-QE-MS non-target metabolomics method for metabolomics analysis of broiler liver using principal component analysis (PCA) and partial least squares discriminant analysis (OPLS-DA). The central venous cells of the broiler liver in the chromium poisoning group showed turbidity and flaky necrosis, nuclear condensation, nuclear rupture, and even nuclear dissolution. The differential metabolite analysis between the chromium poisoning and the control group showed that 32 differential metabolites were upregulated and 15 were downregulated in positive ion mode. Whereas,17 differential metabolites were downregulated, and 35 were downregulated in negative ion mode (P ≤ 0.05). The potential marker substances are oleic acidamide, farnesylacetone, betaine, taurine, choline, and galactinol. Additionally, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways showed that the lipid metabolism, carbohydrate metabolism, nucleotide metabolism, amino acid metabolism, energy metabolism, membrane transport, digestive system, and nervous system were the most important metabolic pathways in the liver. This study provides a theoretical basis for the future understanding of the pathogenesis of chromium poisoning and a new insight of the subsequent molecular mechanism of chromium hepatotoxicity.

Miracle-Gro Singles, Miracle-Gro Shake and Feed, and Vigoro fertilizers are associated with net loss/enhancement of Mn, up to an order of magnitude when referenced to controls in soil, radish vegetables, and radish leaves; Mn enhancements are a factor of 4 to 65 below the daily required intake for humans (2–5.5 mg/day). Manganese levels were measured by atomic absorption spectrometry (AAS). Control soil, radish vegetables, and radish leaves contained 65 μg/g to 146 μg/g (median = 108), 65 μg/g to 357 μg/g (median = 281), and 185 μg/g to 401 μg/g (median = 323) of Mn, correspondingly. Manganese uptake was ten times greater in radish leaves compared to radish vegetables and enhanced by a factor of 3 in soils. Edible radish leaves/vegetables contain 65 times less than human Mn daily requirements. This equates eating 140 lb/day of radish vegetables/leaves. The fertilizers have a minor impact on Mn accumulation in radish leaves/vegetables. The USDA Nutrient Database for radish (0.69 μg/g of Mn) contradicts this notion as one would need to consume ~ 7 to 18 lb/day of radish to satisfy their daily intake. This study complements investigations showing that fertilizers induce minimal uptake of heavy metals in food; simultaneously, the net loss of Mn amounts observed in some samples of radish leaves and vegetables is analogous to the dilution effect of minerals/nutrients in edibles. Although a deficiency/excess of Mn in one’s diet may lead to adverse health effects, background inhalation exposure in general public, occupational, and emergency response settings has a greater influence on one’s propensity toward developing adverse health effects related to Mn inhalation exposure.

Laccases produced by Leucoagaricus gongylophorus act in lignocellulose degradation and detoxification processes. Therefore, the use of L. gongylophorus laccase (Lac1Lg) was proposed in this work for degradation of anthracene and others polycyclic aromatic hydrocarbons without the use of mediators. Degradation reactions were performed in buffer aqueous solution with 10 ppm of anthracene and other PAHs, Tween-20 in 0.25% v/v and a laccase preparation of 50 U. The optimum condition (pH 6.0 and 30 °C) was determined by response surface methodology with an excellent coefficient of determination (R²) of 0.97 and an adjusted coefficient of determination (R²ₐdⱼ) of 0.93. In addition, the employment of the mediator ABTS decreased the anthracene biodegradation from 44 ± 1% to 30 ± 1%. This optimum pH of 6.0 suggests that the reaction occurs by a hydrogen atom transfer mechanism. Additionally, in 24 h Lac1Lg biodegraded 72 ± 1% anthracene, 40 ± 3% fluorene and 25 ± 3% phenanthrene. The yellow laccase from L. gongylophorus biodegraded anthracene and produced anthrone and anthraquinone, which are interesting compounds for industrial applications. Moreover, this enzyme also biodegraded the PAHs phenanthrene and fluorene justifying the study of Lac1Lg for bioremediation of these compounds in the environment.

Natural steroid estrogens (NSEs), including free estrogens (FEs) and conjugated estrogens (CEs), are of emerging concern globally among public and scientific community due to their recognized adverse effects on human and wildlife endocrine systems in recent years. In this review, the properties, occurrence, sorption process, and transformation pathways of NSEs are clarified in the environment. The work comprehensively summarizes the occurrence of both free and conjugated estrogens in different natural and built environments (e.g., river, WWTPs, CAFOs, soil, and sediment). The sorption process of NSEs can be impacted by organic compounds, colloids, composition of clay minerals, specific surface area (SSA), cation exchange capacity (CEC), and pH value. The degradation and transformation of free and conjugated estrogens in the environment primarily involves oxidation, reduction, deconjugation, and esterification reactions. Elaboration about the major, subordinate, and minor transformation pathways of both biotic and abiotic processes among NSEs is highlighted. The moiety types and binding sites also would affect deconjugation degree and preferential transformation pathways of CEs. Notably, some intermediate products of NSEs still remain estrogenic potency during transformation process; the elimination of total estrogenic activity needs to be addressed in further studies. The in-depth researches regarding the behavior of both free and conjugated estrogens are further required to tackle their contamination problem in the ecosystem. Graphical abstract ᅟ

Monitoring of particulate matter (PM) is important in air quality, public health, and epidemiological studies and in decision-making for policy implementation. In the present study, the temporal variability of surface-measured PM concentrations ([PM]) and their relationship with meteorological variables and aerosol optical depth (AOD), with the aid from source apportionment studies, are investigated at four urban cities in the Chinese Yangtze River Delta (YRD) region during January 2014 to December 2017. The annual mean concentrations of [PM₂.₅] ([PM₁₀]) observed at Shanghai (SH), Nanjing (NJ), Hangzhou (HZ), and Hefei (HF) were 46.98 ± 12.21, 54.84 ± 46.14, 52.82 ± 16.98, and 64.03 ± 20.57 μg m⁻³ (68.07 ± 14.33, 96.48 ± 26.86, 83.08 ± 22.38, and 97.61 ± 20.19 μg m⁻³), respectively. However, the [PM] exceeded the Chinese National Air Quality Standards of GB3095-2012, being higher (lower) during winter (summer). The [PM] was found higher in the morning (08:00–10:00 LT) and evening (18:00–20:00 LT) and lower in early morning (04:00 LT) and afternoon (14:00 LT) attributed to the dynamics of boundary layer height and varied emission sources. With an annual mean of 0.6–0.7, the PM ratio (PMr = PM₂.₅/PM₁₀) was observed to have a single peak distribution in all seasons indicating the dominance of fine particles (PM₂.₅). Further, the [PM₁₀] and [PM₂.₅] were highly correlated (r ≥ 0.90) in all cities, with slope > 0.70 representing the abundance of fine particles, except for NJ (< 0.70). A low correlation (< 0.5) was noticed between [PM₁₀] and AOD₅₅₀ suggesting that the aerosol particles had a large influence on AOD, contributing less to PM₁₀. Finally, the concentration bivariate probability function (CBPF) and trajectory statistical models like potential source contribution function (PSCF) and concentration-weighted trajectory (CWT) suggested that local and regional sources contributed a lot for the high [PM₂.₅] observed at the four cities in the YRD, China.

We investigated the effects of sub-chronic exposure to Kalach 360 SL (KL), glyphosate-based herbicide used in Tunisia, on liver and hematological system in different groups of female rats. Group 1 was used as a control, while animals of groups 2 and 3 received orally 0.07 mL and 0.175 mL of KL, respectively (126 and 315 mg of glyphosate/kg), for 60 days. As a result, the KL-exposed groups exhibited hypochromic microcytic anemia, systemic inflammation, cytolysis, decrease in hepatic enzyme activity, and cholestasis. Exposure to different doses of KL could induce erythrocyte destruction (hemolysis) in hematopoietic organs (bones). Moreover, lipid peroxidation contents and protein oxidation markers significantly increased in exposed groups, while enzymatic and non-enzymatic antioxidant activities decreased considerably, in both erythrocytes and liver tissues, compared with those in controls. Liver histological studies confirmed the presence of inflammatory reaction with pathology involving the damage or necrosis of hepatocytes, however, without fibrosis remodulation. Thus, KL sub-chronic exposure caused hepatonecrosis, systemic inflammation, and hemolysis.

Spirotetramat is a toxic commercially known as Movento used to control pistachio psylla pests. In the present study, the effects of Movento on passive avoidance learning of rats and their ability to explore the novel object in the novel object recognition test were investigated. The changes in the concentration of hippocampal brain-derived neurotrophic factor (BDNF) proteins were evaluated, too. Male Wistar rats were gavaged at different dosages of the Movento (50, 100, 250, 500, 1000, 1250, and 1500 mg/kg) or saline for 7 days (administered every 2 days). We showed that Movento caused 50 and 100% mortality at the dose of 1250 and 1500 mg/kg, respectively. At the dose of 1000 mg/kg, Movento significantly decreased locomotor activity (P < 0.05). These rats also displayed a significant decrease in the number of training trials in the shuttle box and the ability to recognize a novel object compared with the control group (P < 0.01). The BDNF protein level of hippocampus also showed a significant decrease in the Movento (1000 mg/kg) compared with the control group (P < 0.01) while the number of pancellular necrosis pyramidal CA1 cells increased significantly in the Movento group (P < 0.001). We concluded that exposure to Movento can decline sensory, motor, and learning in rats.

When using a simulation model to study seawater intrusion (SI), uncertainty in the parameters directly affects the results. The impact of the rise in sea levels due to global warming on SI cannot be ignored. In this paper, the Monte Carlo method is used to analyze the uncertainty in modeling SI. To reduce the computational cost of the repeated invocation of the simulation model as well as time, a surrogate model is established using a radial basis function (RBF)–based neural network method. To enhance the accuracy of the substitution model, input samples are sampled using the Latin hypercube sampling (LHS) method. The results of uncertainty analysis had a high reference value and show the following: (1) The surrogate model created using the RBF method can significantly reduce computational cost and save at least 95% of the time needed for the repeated invocation of the simulation model while maintaining high accuracy. (2) Uncertainty in the parameters and the magnitude of the rise in sea levels have a significant impact on SI. The results of prediction were thus highly uncertain. In practice, it is necessary to quantify uncertainty to provide more intuitive predictions.

To assess the toxicity and accumulation (total and subcellular partitioning) of cadmium (Cd) and mercury (Hg), juvenile eastern oysters, Crassostrea virginica, were exposed for 4 weeks to a range of concentrations (Control, Low (1×), and High (4×)). Despite the 4-fold increase in metal concentrations, oysters from the High-Cd treatment (2.4 μM Cd) attained a body burden that was only 2.4-fold greater than that of the Low-Cd treatment (0.6 μM Cd), while oysters from the High-Hg treatment (0.056 μM Hg) accumulated 8.9-fold more Hg than those from the Low-Hg treatment (0.014 μM Hg). This fold difference in total Cd burdens was, in general, mirrored at the subcellular level, though binding to heat-denatured proteins in the High-Cd treatment was depressed (only 1.6-fold higher than the Low-Cd treatment). Mercury did not appear to appreciably partition to the subcellular fractions examined in this study, with the fold difference in accumulation between the Low- and High-Hg treatments ranging from 1.5-fold (heat-stable proteins) to 4.6-fold (organelles). Differences in toxicological impairments (reductions in condition index, protein content, and ETS activity) exhibited by oysters from the High-Cd treatment may be partially due to the nature of how different metals partition to subcellular components in the oysters, though exact mechanisms will require further examination.

Accurate quantification of the emission of CO₂ from streams and rivers is one of the primary challenges in determining the global carbon budget because our knowledge of the spatial and seasonal heterogeneity on these CO₂ emissions is limited. In karst areas, the groundwater-stream continuum is likely ubiquitous because the carbon-rich groundwater discharges into some of the streams through springs or subterranean streams, which results in more complex spatial and seasonal variations in the CO₂ emissions. To address this issue, the spatial and seasonal characteristics of partial pressure of CO₂ (pCO₂), the δ¹³CDIC, and the CO₂ emission flux of the Guancun surface stream (GSS) karst groundwater-stream continuum in southern China were investigated from the stream head (groundwater outlet) to the downstream mouth during the 2014–2017 period. Our results reveal that the pCO₂ and CO₂ emissions exhibit high spatial and seasonal heterogeneities over ~ 1300 m in the GSS. Spatially, the pCO₂ and CO₂ emissions decrease sharply from the stream head (mean 8818.4 μatm for pCO₂ and mean 423.4 mg m⁻² h⁻¹ for CO₂ emission) to the site farthest downstream (mean 2752.7 μatm for pCO₂ and 257.0 mg m⁻² h⁻¹ for CO₂ emission). Except for the dates when extreme rainfall occurred, the pCO₂ and CO₂ emission values were higher in the rainy season than in the dry season. This suggests that in a groundwater-stream continuum, CO₂ emission occurs very soon after the water is transferred from the karst groundwater to the surface water. We estimate that the total amount of CO₂ released to the atmosphere from the GSS is 21.75 t CO₂/year, which is only 1.71–5.62% of the dissolved inorganic carbon loss flux in the GSS during the study period. It is important to note that the measured CO₂ emission and pCO₂ levels decrease farther downstream, so carbon loss is underestimated when it is calculated using downstream sampling points. Therefore, accurate assessments of the CO₂ emission flux need to take into consideration the high spatio-temporal heterogeneity in order to reduce the bias of the entire CO₂ emission flux.