Monitoring and dietary exposure assessment of pesticide residues in strawberry in Beijing, China.

In this study, 142 pesticide residues in 245 strawberry samples, gathered from farmers markets or supermarkets in Beijing from June 2017 to May 2018, were investigated. The samples were analysed by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). According to the validation data, including linearity, recovery, precision and measurement uncertainty, the method performed well in monitoring pesticide residues and complied with the requirements of the European Guideline SANTE/11813/2017.

Nanoselenium transformation and inhibition of cadmium accumulation by regulating the lignin biosynthetic pathway and plant hormone signal transduction in pepper plants.

Selenium (Se) can promote the growth and resistance of agricultural crops as fertilizers, while the role of nano-selenium (nano-Se) against Cd remains unclear in pepper plants (Capsicum annuum L.). Biofortification with nano-Se observably restored Cd stress by decreasing the level of Cd in plant tissues and boosting the accumulation in biomass.

Diagnostic performances of the KWAK-TIRADS classification, elasticity score, and Bethesda System for Reporting Thyroid Cytopathology of TI-RADS category 4 thyroid nodules.

Objective: To explore the value of the KWAK Thyroid Imaging Reporting and Data System (KWAK-TIRADS), elasticity score (ES), and Bethesda System for Reporting Thyroid Cytopathology (BSRTC) in the diagnosis of suspicious thyroid nodules.

Materials And Methods: The study included 392 cases of TI-RADS category 4 thyroid nodules that underwent thyroidectomy between January 2017 and October 2019. All patients underwent ultrasonography, ultrasound elastography, and fine-needle aspiration cytology (FNAC) before surgery.

The Role of Surface Termination in Halide Perovskites for Efficient Photocatalytic Synthesis.

Halide perovskites have received attention in the field of photocatalysis owing to their excellent optoelectronic properties. However, the semiconductor properties of halide perovskite surfaces and the influence on photocatalytic performance have not been systematically clarified. Now, the conversion of triose (such as 1,3-dihydroxyacetone (DHA)) is employed as a model reaction to explore the surface termination of MAPbI .

Remediation of 1-Nitropyrene in Soil: A Comparative Study with Pyrene.

Nitrated polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants, which exhibits higher toxicity than their corresponding parent PAHs (PAHs). Recent studies demonstrated that the PAHs could represent major soil pollution, however the remediation of PAHs has been rarely reported. In this study, biological, physical, and chemical methods have been applied to remove 1-nitropyrene, the model PAH, in contaminated soil.

Development of a QuEChERS-Based Method for Determination of Carcinogenic 2-Nitrofluorene and 1-Nitropyrene in Rice Grains and Vegetables: A Comparative Study with Benzo[a]pyrene.

Nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) are ubiquitous environmental pollutants attracting increasing attention because of their potent mutagenicity to humans. Previous studies of nitro-PAHs focused on investigating their formation mechanisms and detecting them in atmospheric environment; however, few studies have reported their occurrence in food samples, and regulations on nitro-PAHs are still lacking. We report in this study the development and application of a quick, easy, cheap, effective, rugged, and safe (QuEChERS) method for determination of nitro-PAHs in rice and vegetable samples.

Quantitation of Aristolochic Acids in Corn, Wheat Grain, and Soil Samples Collected in Serbia: Identifying a Novel Exposure Pathway in the Etiology of Balkan Endemic Nephropathy.

While to date investigations provided convincing evidence on the role of aristolochic acids (AAs) in the etiology of Balkan endemic nephropathy (BEN) and upper urothelial cancer (UUC), the exposure pathways by which AAs enter human bodies to cause BEN and UUC remain obscure. The goal of this study is to test the hypothesis that environmental pollution by AAs and root uptake of AAs in the polluted soil may be one of the pathways by which AAs enter the human food chain. The hypothesis driving this study was that the decay of Aristolochia clematitis L.

Determination of DNA adducts by combining acid-catalyzed hydrolysis and chromatographic analysis of the carcinogen-modified nucleobases.

The commonly used method of analyzing carcinogen-induced DNA adducts involves the hydrolysis of carcinogen-modified DNA samples by using a mixture of enzymes, followed by (32)P-postlabeling or liquid chromatography (LC)-based analyses of carcinogen-modified mononucleotides/nucleosides. In the present study, we report the development and application of a new approach to DNA adduct analysis by combining the H(+)/heat-catalyzed release of carcinogen-modified nucleobases and the use of LC-based methods to analyze DNA adducts. Results showed that heating the carcinogen-modified DNA samples at 70 °C for an extended period of 4 to 6 h in the presence of 0.

Combination of precolumn nitro-reduction and ultraperformance liquid chromatography with fluorescence detection for the sensitive quantification of 1-nitronaphthalene, 2-nitrofluorene, and 1-nitropyrene in meat products.

Carcinogenic nitropolycyclic aromatic hydrocarbons (nitro-PAHs) are ubiquitous in the ambient environment. They are emitted predominantly from internal combustion engines and by reacting polycyclic aromatic hydrocarbons with nitrogen oxide. The emerging evidence that nitro-PAHs are taken up by plants and bioaccumulatd in the food chain has aroused worldwide concerns for the potential of chronic poisoning through dietary intake.

Influence of different planting seasons of six leaf vegetables on residues of five pesticides.

To investigate the influence of different planting seasons on the dissipation of pesticides, field experiments of thiophanate-methyl, metalaxyl, fluazifop-P-butyl, chlorpyrifos, and λ-cyhalothrin on six crops including pakchoi, rape, crown daisy, amaranth, spinach, and lettuce were designed and conducted. In this study, a high-performance liquid chromatography and electrospray ionization-tandem mass spectrometer with multiple reaction monitoring was used to simultaneously determine thiophanate-methyl and its metabolite carbendazim, metalaxyl, and fluazifop-P-butyl in various samples; gas chromatography with an electron capture detector was used to detect chlorpyrifos and λ-cyhalothrin. The limits of quantitation (LOQs) of these six pesticides were in the range of 0.

Spinach or amaranth contains highest residue of metalaxyl, fluazifop-P-butyl, chlorpyrifos, and lambda-cyhalothrin on six leaf vegetables upon open field application.

To select representative leaf vegetables which may contain the highest residue, field experiments of metalaxyl, fluazifop-P-butyl, chlorpyrifos, and lambda-cyhalothrin on six crops including pakchoi, rape, crown daisy, amaranth, spinach, and lettuce were designed and conducted. In this study, a high-performance liquid chromatograph and electrospray ionization tandem mass spectrometer with multiple reaction monitoring was used to simultaneously determine metalaxyl and fluazifop-P-butyl residue in various samples, and a gas chromatograph with electron capture detector was used to detect chlorpyrifos and lambda-cyhalothrin. The limits of quantification (LOQ) of metalaxyl, fluazifop-P-butyl, chlorpyrifos, and lambda-cyhalothrin were in the range of 0.

Uniconazole residue and decline in wheat and soil under field application.

Uniconazole residue dynamics and final residues in supervised field trials at GAP conditions were studied. The residue levels and dissipation rate of uniconazole was detected by LC-MS. At fortification levels of 0.