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Continuous exposure to airborne pesticides causes their gradual accumulation in the human body, eventually posing a threat to human health. To the best of our knowledge, risk assessment study of pesticide non-occupational exposure to residents in agricultural areas has not been conducted in China. In this study, air samples (gas and dust) were collected from inside and outside residences of seven households and an area near the field in a grain-growing area (wheat and maize rotation) for eight months, and the pesticides present were examined both qualitatively and quantitatively. Using a 95% confidence interval, 9 out of 16 pesticides were detected, namely acetamiprid, acetochlor, atrazine, flucarbazone-sodium, imidacloprid, methyldisulfuron-methyl, nicosulfuron-methyl, pendimethalin, and beta-cyhalothrin, and their safety was subsequently evaluated. The results showed that the inhalation exposure of households to beta-cyhalothrin exceeded the acceptable range in the first residential, and the excess lifetime cancer risk of acetochlor inhalation exposure in six households and area around the field exceeds 1E−6, which highlights the need to strengthen preventive screening for cancer risk. [ABSTRACT FROM AUTHOR]

In comparison to an open field, greenhouses utilize much more pesticides. The non-occupational exposure risk caused by pesticide drift is unknown. In this study, within 8 months (from March 2018 to October 2018), air samples were collected from indoor and outdoor houses and public areas near greenhouses in vegetable growing areas (eggplant, leek, garlic, etc.), and qualitative and quantitative analyses of pesticides were carried out. Using a 95% confidence interval, six pesticides (acetamiprid, difenoconazole, thiazophos, isoprocarb, malathion, and pyridaben) were detected. The results of the safety assessment showed that the non-cancer exposure risk of single pesticides for all residents in the agricultural areas was within the acceptable range, and the excess lifetime cancer risk of all residents inhaling difenoconazole exceeded 1E−6, and the agricultural region urgently needs increased cancer regulatory scrutiny. But combined toxicity of six pesticides not evaluated due to lack of suitable data. Comparison with open field scenes, the results show that pesticide levels to airborne are lower in greenhouse regions. [ABSTRACT FROM AUTHOR]

Rechargeable aluminum‐ion batteries have attracted significant attention as candidates for next‐generation energy storage devices owing to their high theoretical capacity, safe performance, and abundance of raw materials. Al metal is the best option as the negative electrode, while its issues such as dendrite growth and corrosion accompanying hydrogen evolution in ionic liquid electrolyte have been seriously overlooked. Understanding the electrochemical mechanism of the surface evolution behavior of Al metal is a vital pathway for solving these issues. Kinetic parameters and electrode structure are the two key parameters that affect the surface evolution behavior of Al negative electrodes. Herein, the qualitative relationship between the kinetic parameters and surface evolution behavior of the Al negative electrode was established through a combination of in‐situ optical technology and multi‐physical field numerical simulation method. The key kinetic parameters, including ion concentration and transfer coefficient, exhibited different laws of influence on the surface evolution behavior, such as dendrite growth and corrosion. The electrochemical mechanism on the surface evolution was explored to guide the optimization design of Al‐ion batteries. Based on the coupling design of the electrode structure and kinetic parameters, a highly stable porous aluminum structure composed of Al powder with a particle size of 100 μm was constructed to obtain highly stable and high‐performance aluminum‐ion batteries. This method provides new sight into the design of high‐performance aluminum‐ion batteries. [ABSTRACT FROM AUTHOR]

Rechargeable Al-ion batteries (AIBs) are considered as one of the most fascinating energy storage systems due to abundant Al resource and low cost. However, the cycling stability is subjected to critical problems for using Al foil as negative electrode, including Al dendrites, corrosion and pulverization. For addressing these problems, here a lightweight self-supporting N-doped carbon rod array (NCRA) is demonstrated for a long-life negative electrode in AIBs. Experimental analysis and first-principle calculations reveal the storage mechanism involving the induced deposition of N-containing function groups to Al as well as the ideal skeleton of the NCRA matrix for Al plating/stripping, which is favorable for regulating Al nucleation and suppressing dendrites growth. Compared with the Al foil, the NCRA exhibits lower areal mass density (∼ 72% of Al foil), smaller thickness (40% of Al foil), but much longer cycle life (> 4 times of Al foil). Benefiting from the remarkable stability of the array structure, symmetric cells show excellent cycling stability with small voltage hysteresis (∼ 80 mV) and meanwhile there are no corrosion and pulverization problems even after cycled for 120 hours. Besides, full cells also manifest long lifespan (1,500 cycles) and increased Coulombic efficiency (100±1%). [ABSTRACT FROM AUTHOR]

The production and export volume of fruits from China are among the top three in the world. Pesticides are applied to orchards more than 10 times a year to control pests, and stretcher-type power sprayers are widely used to apply chemical pesticides. However, an assessment of pesticide-handler exposure to pesticides in this scenario has not been reported in China. The test pesticide, 30% SYP-9625 concentrate diluted 3000 times, was sprayed on apple orchards in Beijing China. Experiments were conducted to assess dermal and inhalation exposure using standard whole-body dosimetry and air-sampling methodologies. The dermal deposition was the main route of exposure in this study. The dermal unit exposure (UE) of handlers was 350 mg·kg−1 a.i. of SYP-9625. The hands accounted for 59% of the total exposure and were the most exposed body part. Inhalation UE was 0.720 mg·kg−1 a.i. of SYP-9625 and was negligible compared with dermal exposure. We found that use of protective garments while using stretcher-type powers sprayers reduced dermal pesticide exposure. These results can be used as a reference for the handler's safety in pesticide management and orchard mechanical management. [ABSTRACT FROM AUTHOR]

Triazide herbicides were widely used in China. Triazine herbicides belong to the environmental hormone and mainly affect the endocrine system, which have potential carcinogenic effects. Low content of triazine compounds in the environment was detected by isotope dilution mass spectrometry more sensitive and accurate than others. Therefore, prometryn-13C3, simetryn-13C3, terbuthylazine-13C3 and terbutryn-13C3 were first successfully synthesised with good yield and high purity. A reliable and sensitive isotope-labelled internal standard method was developed for simultaneous determination of prometryn, simetryn, terbuthylazine and terbutryn in soil using ultrahigh-performance liquid chromatography-tandem mass spectrometry was developed. Isotope-labelled internal standards could effectively overcome the matrix effect. The recoveries in the soil at three spiking levels (10, 20, 50 μg·kg−1) ranged from 92.3% to 105.2%, with all relative standard deviations being less than 9.6% for all analytes. The limits of detection and the limits of quantification were below 0.06 and 0.2 μg·kg−1, respectively. The method was demonstrated to be convenient and accurate for the routine monitoring of prometryn, simetryn, terbuthylazine and terbutryn in the soil to provide a reference to the environmental management of China. [ABSTRACT FROM AUTHOR]

The Claisen condensation reaction is a classical method used for the formation of C−C bonds. Homo‐ and cross‐Claisen condensation reactions are usually carried out using a Ti(IV)‐based reagent at ultra‐low‐temperatures. In this report, intermediate β‐keto acyl imidazoles were synthesised using a sodium imidazolide‐catalysed homo‐ and cross‐condensation reaction of N‐acyl imidazoles performed under mild conditions and subsequently used to prepare a range of β‐keto esters and ketones via alcoholysis or hydrolysis. This method is particularly suitable for the synthesis of isotopically‐labelled acetylacetic ester compounds. N‐acyl imidazole compounds are useful reactants for the Claisen condensation reaction. [ABSTRACT FROM AUTHOR]

BACKGROUND Neonicotinoid insecticides (NIs) have been recently banned in some countries because of increased pest resistance and deleterious risks to non‐target organisms. Recent studies considered all parts of crops as a whole part in plant protection. However, there are few reports focused on the distribution and metabolic trends of NIs on target feeding sites of different pests in apple orchards. RESULTS: The spatial and temporal distribution, absorption, degradation, and metabolism of three NIs, imidacloprid, acetamiprid, and thiamethoxam, on different parts of apple trees were studied under foliar spray and root irrigation treatments. In the spray treatment, the initial average concentration ratios (TCRs) were 31.6% for lower shoots, 23.3% for upper leaves, 23.2% for upper shoots, 21.0% for lower leaves, and 0.5% and 0.4% for upper and lower fruits, respectively. The average half‐lives of the three NIs were 2.9 days for shoots, 7.4 days for leaves, and 10.8 days for fruits. The degradation rate of shoots was 2.5 times that of leaves, and 3.6 times that of fruits. Imidacloprid olefin and N‐methyl acetamiprid were two of the main metabolites. In the root treatment, both roots and soils had high TCRs during the whole sampling period. Only imidacloprid was transmitted to above‐ground parts of the plants, with TCRs of 0.38–50.94%. CONCLUSION: This study found significant differences in spatial and temporal distribution, degradation, metabolism, and trends of NIs on different pest target sites of apple trees. The data obtained may help promote scientific control of target pests and evaluation of safety for non‐target species in orchards. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Phytophthora capsici is a devastating pathogen for crop. Cellulose synthase 3 (CesA3) is a target for many potential fungicides such as valinamide derivatives. However, the 3‐dimensional structure (3‐DS) of CesA3 in Phytophthora capsici was still unknown. RESULTS: Here CesA3 protein sequence was retrieved from the NCBI protein sequence database We did the 3‐DS structural modeling for CesA3 and used molecular dynamics to optimize the model. The model was further validated by the Ramachandran plot in PROCHECK program. Two series of new valinamide compound were synthesized and tested for its biological activity. The docking data obtained by the model perfectly matched with the biometric data, indicating that the model is valid. Moreover, docking study data revealed the mechanism of action of inhibitors on target enzymes. CONCLUSION: The 3‐DS structural model was analyzed from the perspective of the biocide receptor, the structure of the target protein and the mechanism of action of the compound. It provides a new perspective for the design of new fungicides. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Treated soil is the second most prevalent application technique for all registered pesticides in China. Some developing countries also adopt this method. However, the safety of this scenario has not been reported in the literature. Experiments were therefore conducted to assess exposure using standard whole-body dosimetry and air sampling methodologies. RESULTS Dermal deposition was the main route of exposure in this scenario. The total dermal unit exposure ( UE) of operators to clothianidin-treated soil was 51.7 mg kg−1 AI handled ( SD = 20.59, n = 16), and hands accounted for 36%. Inhalation UE was 0.04 mg kg−1 AI handled ( SD = 0.02, n = 4), negligible compared with dermal exposure. Using an NOAEL (no observed adverse effect level) of 10 mg kg−1 day−1, the margin of exposure was 773, i.e. greater than 100. CONCLUSION For the first time, the scenario of treated soil exposure was assessed and was found to pose less risk than conventional pesticide application. These results can be used as a reference in pesticide management. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The coffee bean weevil (CBW), Araecerus fasciculatus (De Geer, 1775) (Coleoptera: Anthribidae) is an important pest of stored products such as grains, coffee beans, cassava, and traditional Chinese medicine materials. In China, CBW causes large losses of Daqu, a traditional Chinese liquor fermentation starter, and, unfortunately, the use of conventional insecticides against CBW is not suitable in Daqu storage. We found CBW to be highly attracted to fermenting yeast cultures, such as Kluyveromyces lactis. Eight volatile compounds, produced by fermenting cultures and not by sterile samples, were identified by gas chromatography coupled with mass spectrometry. Five of these substances elicited significant responses in Y-tube behavioral bioassays. Field trapping experiments revealed 2-phenylethanol and 2-phenylethyl acetate to be crucial for attraction of CBW. Results show that yeast volatiles play an important role in host location, and that 2-phenylethanol and 2-phenylethyl acetate could be utilized as potential attractants in monitoring and control systems against this important pest. [ABSTRACT FROM AUTHOR]

BACKGROUND To date, no research has been conducted to establish exposure levels for occupational pesticide operators under typical use scenarios in China. Through surrogate skin techniques (the whole-body method), the authors monitored dermal and inhalation exposure of pesticide applicators in China. In addition, the exposure of pesticide mixers was analysed. RESULTS The total dermal exposure of inexperienced and experienced applicators was respectively 4037 and 536 mg kg−1 of active ingredient ( AI) handled for application to maize that was <80 cm in height. The exposure level was highest on hands; the closer to the hands, the lower arms and the upper legs, the higher the exposure. The unit exposure of mixers differed according to the formulation; exposure to emulsifiable concentrate ( EC) and oil-in-water emulsion ( EW) was greater than exposure to wettable powder ( WP) or wettable dispersible granules ( WG). The unit exposure of mixers via inhalation was significantly greater than that of applicators when chlorpyrifos (48% EC) was used ( P < 0.0001). CONCLUSIONS The main objectives of this study were to provide an indication of the realistic exposure risk of mixers and applicators, and to contribute useful information for risk mitigation and management and epidemiological studies in China. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A series of novel (4′-tosyl) piperidin-4-yl containing α-aminophosphonates were synthesized by a one-pot reaction, efficiently catalyzed by magnesium perchlorate, under solvent-free conditions from 1-tosylpiperidin-4-one, substituted aromatic amines, and diethyl phosphite (DEP). The synthesized compounds were characterized by IR,1H NMR,13C NMR,31P NMR, and HRMS spectroscopy. A single-crystal X-ray structure of diethyl 4-(2-chlorophenyl) amino-1-(4’-methylbezenesulfonyl) piperidin-4-yl-phosphonate (2a) was obtained, and some of the title compounds displayed insecticidal activities againstPlutella xylostella. Supplementary materials are available for this article. Go to the publisher's online edition ofPhosphorus, Sulfer, and Silicon and the Related Elementsfor the following free supplemental files: Additional figures and tables. [ABSTRACT FROM PUBLISHER]

The phase behavior of the system of surfactant SAA [0203B, nonionic surfactant 700# and methanol (weight ratio=6&ratio;1&ratio;1)]/mixed oil [beta‐cypermethrion, dimethyl benzene and cyclohexanone (weight ratio=2&ratio;2&ratio;1,or 0&ratio;2&ratio;1)]/water [distilled water (0 mg/L), or standard water (342 mg/L), or ultra‐hard water (500 mg/L)] has been studied in a pseudoternary phase diagram at 25 ± 1°C. Our results indicated that the isotropic monophasic area in the phase diagrams decreased significantly as the beta‐cypermethrion was added in the oil phase. In an attempt to the microemulsion electrical condectivity can be define regions corresponding to three structure states W/O, B.C., and O/W type in the microemulsion domain. The influence of beta‐cypermethrion on their regions sequences B.C. > O/W≫W/O type. This work will be beneficial to improving the quality of beta‐cypermethrion microemulsion and make it more competitive in the market. [ABSTRACT FROM AUTHOR]

Atrazine is a long-lasting herbicide that has been shown to affect hormone levels in amphibians. Using the C-13 labeled atrazine to detect its residue is effective and essential. This study presents three steps for the synthesis of [13C3]atrazine, which starts from [13C]urea, and results in the incorporation of C-13 atoms at the 1, 3 and 5 positions of the S-triazine ring of atrazine. The method prepares the product in an overall yield of 57.6% and chemical purity of 98.6%, for use as an internal standard. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]