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Rapid and efficient detection of mycotoxins is of great significance in the field of food safety. In this review, several traditional and commercial detection methods are introduced, such as high-performance liquid chromatography (HPLC), liquid chromatography/mass spectrometry (LC/MS), enzyme-linked immunosorbent assay (ELISA), test strips, etc. Electrochemiluminescence (ECL) biosensors have the advantages of high sensitivity and specificity. The use of ECL biosensors for mycotoxins detection has attracted great attention. According to the recognition mechanisms, ECL biosensors are mainly divided into antibody-based, aptamer-based, and molecular imprinting techniques. In this review, we focus on the recent effects towards the designation of diverse ECL biosensors in mycotoxins assay, mainly including their amplification strategies and working mechanism. [ABSTRACT FROM AUTHOR]

Agricultural soil contaminated with potentially toxic metals poses great health risk to humans and it requires long-term remediation. Here, we investigate the remediation of metal-polluted agricultural soil by combining chemical washing with repeated phytoextraction. The polluted field was initially washed with 40 mmol L−1 FeCl3 (F) or 20 mmol L−1 FeCl3 + 40 mmol L−1 citric acid (F + C). After the application of organic fertilizer (O), lime (L), and sepiolite (S), Sedum plumbizincicola was cultivated for three successive crops from 2017 to 2019. Results showed that the soil washed with FeCl3 had high removal efficiencies of Cd (35.2%), Pb (24.3%), and Zn (26.6%). Although the shoot biomass and metal concentrations of S. plumbizincicola decreased significantly in the first crop, there were no significant differences in the subsequent two crops. Throughout the remediation process, the higher total removal efficiencies of Cd, Pb, and Zn were conducted in F + OLS treatment which observed in 71.0, 34.0, and 47.7%, respectively. The results, therefore, conclusively indicated that combining chemical washing with repeated phytoextraction showed considerable potential for the remediation of agricultural soils polluted with multiple metals. However, further studies are required to focus on the amelioration of the degraded soil quality and safe agricultural production. [ABSTRACT FROM AUTHOR]

Purpose: Batch extraction experiments were conducted to investigate the chemical washing of metal-contaminated paddy soils using mixtures of ferric chloride (FeCl3) and citric acid (CTA).Materials and methods: The effects of the extractants (FeCl3, CTA, or FeCl3 + CTA) and washing cycles (single-step or multistep washing) on the metal removal efficiency were studied. FeCl3 + CTA increased metal removal efficiency to some extent compared to single FeCl3 or CTA. When the liquid-to-solid ratio was 2:1 with three washes and two rinses, a mixture of 10 mmol L−1 FeCl3 and 20 mmol L−1 CTA removed 78.9% Cd, 15.8% Cu, 34.0% Zn, and 18.1% Pb from a Typic Fe–accumuli–Stagnic Anthrosols. Using multistep washing instead of single-step increased the metal extraction effect. Moreover, the removal efficiency and speciation of metals in different soils and changes in soil properties in washed soils were also studied.Results and discussion: The removal rate of Cd was higher than that of Zn, Cu, or Pb because of the higher proportions of acid-soluble forms of Cd in the soils. The removal of metals from different soils depended on the distribution of metal speciation and soil type. Soil pH, CEC, exchangeable Ca, and exchangeable Mg decreased significantly after soil washing.Conclusions: We conclude that chemical washing of metal-contaminated paddy soils with mixtures of FeCl3 and citric acid may be a feasible technique for soil remediation. [ABSTRACT FROM AUTHOR]

The degradation of p-nitrochlorobenzene (p-NCB) in soil by zero-valent iron-activated persulfate is of environmental and applied significance. In this study, the effects of initial pH and temperature on the removal of p-NCB by Fe0-activated persulfate were investigated. The results demonstrated that both initial pH and temperature played an important role in the degradation of p-NCB and the removal of p-NCB increased from 20.9% at pH 10.0 to 97.3% at pH 3.0 and from 60.9% at 15 °C to 96.2% at 35 °C. The kinetic curves were best fitted to zero order kinetic equation at low dosage of the zero-valent iron, and the activation energy was calculated to be 26.88 kJ·mol-1. However, the reaction followed first order kinetic at high dosage of the zero-valent iron, and the activation energy was 31.79 kJ·mol-1. The degradation intermediates of p-NCB were analyzed with GC-MS, which mainly included 4-chloroaniline,1-(4-chlorophenyl)-3-phenlurea,5-chloro-2-(4-chlorophenyl diazenyl)phenol and 1,4-benzoquinone. In the system of Fe0-activated persulfate, a nitro group was first reduced to amine group and p-chloroaniline was easier to be oxidized than p-NCB. Therefore, it was concluded that the Fe0-activated persulfate was an effective approach to removal of p-NCB in soil. [ABSTRACT FROM AUTHOR]

Interactions between anions and cations are important for understanding the behaviors of chemical pollutants and their potential risks in the environment. Here we prepared soil aggregates of a yellow paddy soil from the Taihu Lake region, and investigated the effects of phosphate (P) pretreatment on adsorption-desorption of Cu 2+ of soil aggregates, free iron oxyhydrates-removed soil aggregates, goethite, and kaolinite with batch adsorption method. The results showed that Cu 2+ adsorption was reduced on the aggregates pretreated with low concentrations of P, and promoted with high concentrations of P, showing a V-shaped change. Compared with the untreated aggregates, the adsorption capacity of Cu 2+ was reduced when P application rates were lower than 260, 220, 130 and 110 mg/kg for coarse, clay, silt and fine sand fractions, respectively. On the contrary, the adsorption capacity of Cu 2+ was higher on P-pretreated soil aggregates than on the control ones when P application rates were greater than those values. However, the desorption of Cu 2+ was enhanced at low levels of P, but suppressed at high levels of P, displaying an inverted V-shaped change over P adsorption. The Cu 2+ adsorption by the aggregate particles with and without P pretreatments was well described by the Freundlich equation. Similar results were obtained on P-pretreated goethite. However, such P effects on Cu 2+ adsorption-desorption were not observed on kaolinite and free iron oxyhydrates-removed soil aggregates. The present results indicate that goethite is one of the main soil substances responsible for the P-induced promotion and inhibition of Cu 2+ adsorption. [ABSTRACT FROM AUTHOR]