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Cesium copper halide (CCH) nanocrystals (NCs) have gained significant interest as a Pb-free alternative to conventional cesium lead halide NCs in fabricating LEDs due to their broadband emission. An in-depth analysis of the origin of such broadband emission in colloidal CCH NCs is presented in this work. Further, the effect of introducing Mn as an emission center in CCH by in situ doping facilitates easy energy transfer to analytes exhibiting remarkable picomolar sensitivity (1.86 pM) toward bentazone (analyte) which otherwise was difficult to achieve, even microlevel sensitivity. A mechanism that can predict the success of sensitized dopant emission and guide the design of host–guest combinations has been systematically elucidated. [ABSTRACT FROM AUTHOR]

In this study, a resonance Rayleigh scattering technique-based sensing method for detecting Bentazone residual in water samples has been developed. This technique was carried out using chitosan-capped gold nanoparticles with a spectrofluorimetric method. Experimental results revealed that the developed method could allow the detection of Bentazone residual as low as a concentration of 0.02 ng mL−1 within 50-sec time. Overall results confirmed the very low detection limit for measuring the Bentazone. The chitosan-capped gold nanoparticles as an excellent sensor were applied to measure and analyze Bentazone in water samples. This article developed a resonance Rayleigh scattering technique-based sensing method for the detection of bentazone residual in water samples. This technique was carried out using chitosan-capped gold nanoparticles with spectrofluorimetric method. Because, Chitosan-capped AuNPs have exciting features, such as resonance Rayleigh scattering (RRS). Use of Chitosan-capped AuNPs sensor as an inexpensive valuable resource, and nontoxic. Chitosan has no toxicity, does not cause allergies and irritations, and is biodegradable and biocompatible. Chitosan-capped AuNPs have exciting features, such as resonance Rayleigh scattering (RRS). These properties are enhanced and modified by adding a hydrophilic polymer such as natural chitosan. [ABSTRACT FROM AUTHOR]

Weeds alone cause a 37% loss in attainable soybean production. Bentazone is a postemergence herbicide used to control broadleaf weeds in the cultivation of cereals, legumes, vegetables, and tuber crops. This study aimed to screen the Korean collections of cultivated soybeans in relation to bentazone, identifying the genetic loci controlling bentazone reactions to cultivated soybean collections using a genome-wide association study (GWAS). This study identified bentazone-tolerant and bentazone-sensitive soybean germplasms from 418 cultivated soybean germplasms and found that moderate bentazone tolerance predominated in the Korean collection of cultivated soybeans. The GWAS revealed that 42 SNPs distributed on chromosomes 3, 5, 6, 13, and 20 were strongly associated with the bentazone reaction in 418 cultivated soybean accessions over three years. Of these loci, a genomic region on chromosome 5 contained significant SNPs and was identified as being involved in the bentazone reaction in both 2020 and 2021, based on FarmCPU analysis. By conducting a haplotype analysis, this study identified five putative genes, namely, Glyma.05g145000 (ATP-binding cassette transporter), Glyma.05g145100 (unknown), Glyma.05g145200 (ankyrin repeat family protein), Glyma.05g145300 (transmembrane amino acid transporter protein), and Glyma.05g145400 (unknown). Further studies are required to confirm the involvement of the putative genes in the bentazone reaction by comparing their expression levels between bentazone-tolerant and bentazone-sensitive plants. Therefore, the results of this study can be used for marker-assisted selection in programs for the breeding of herbicide-tolerant soybeans. [ABSTRACT FROM AUTHOR]

Soybean (Glycine max (L.) Merr.) is one of the most economically important crops in the world due to its nutritional value. To optimize soybean growth and yield, a wide range of commercial herbicides intended for weed control in crops are used. Although the herbicides used are selective, they can still cause oxidative stress and disturb photosynthetic reactions in soybean crops. In this work, the influence of commercial selective herbicides for weed control on the photosynthetic efficiency and antioxidative response of two soybean cultivars was investigated. The parameters describing the photosynthetic performance of soybean were derived by measuring in vivo chlorophyll a fluorescence while the antioxidative response was evaluated by determining activities of the selected antioxidative enzymes and parameters of oxidative stress at different development stages. The results showed a different response of the two soybean cultivars to herbicide treatment. Both investigated soybean cultivars showed that herbicide treatment did not cause oxidative damage. However, they revealed different adaptation mechanisms of photosynthetic apparatus. A negative impact of herbicide application was observed mainly on the electron transport chain in both varieties. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Hydrobiology / Shuisheng Shengwu Xuebao is the property of Editorial Department of Journal of Hydrobiology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Removal of bentazone herbicide through photodegradation process using nanostructured TiO2 / Clinoptilolite composite was studied to investigate the potential of clinoptilolite natural support and the effect of the loaded TiO2 content on the process efficiency. For this purpose, TiO2 /Clinoptilolite photocatalysts containing different amounts of titania (10, 20, 30, 40 wt.%) were synthesized using a simple and inexpensive wet impregnation method and characterized by XRD, FESEM, EDX, BET, PL, and UV-vis analyses. The characterization results confirmed the successful synthesis of nanocomposite samples and showed that the use of zeolitic support, reducing the recombination rate of electron-hole pairs, improves the dispersion of titania nanoparticles and reduces the accumulation of these particles. The performance results showed that by increasing the TiO2 loading up to 30 wt.%, the removal efficiency of bentazone increases, which is due to the greater number of available active sites. By further increasing the amount of TiO2 loading, the percentage of photocatalytic removal decreases because of the increment in the number of agglomerations on the catalyst surface and the decrement in the adsorption capacity. Also, the kinetic studies show a higher rate of bentazone degradation over the sample containing 30 wt.% of titania and the results follow the first-order kinetic reaction. In order to ensure the efficiency of the selected photocatalyst in the removal of other agricultural pesticides, its efficiency in the photocatalytic removal of paraquat herbicide was also evaluated, which showed good performance. Thus, it can be concluded that the immobilization of the optimal amount of titania on clinoptilolite, in addition to better and easier separation, leads to improved optical and structural properties, and ultimately increased photocatalytic performance. [ABSTRACT FROM AUTHOR]

Weeds alone cause a 37% loss in attainable soybean production. Bentazone is a postemergence herbicide used to control broadleaf weeds in the cultivation of cereals, legumes, vegetables, and tuber crops. This study aimed to screen the Korean collections of cultivated soybeans in relation to bentazone, identifying the genetic loci controlling bentazone reactions to cultivated soybean collections using a genome-wide association study (GWAS). This study identified bentazone-tolerant and bentazone-sensitive soybean germplasms from 418 cultivated soybean germplasms and found that moderate bentazone tolerance predominated in the Korean collection of cultivated soybeans. The GWAS revealed that 42 SNPs distributed on chromosomes 3, 5, 6, 13, and 20 were strongly associated with the bentazone reaction in 418 cultivated soybean accessions over three years. Of these loci, a genomic region on chromosome 5 contained significant SNPs and was identified as being involved in the bentazone reaction in both 2020 and 2021, based on FarmCPU analysis. By conducting a haplotype analysis, this study identified five putative genes, namely, Glyma.05g145000 (ATP-binding cassette transporter), Glyma.05g145100 (unknown), Glyma.05g145200 (ankyrin repeat family protein), Glyma.05g145300 (transmembrane amino acid transporter protein), and Glyma.05g145400 (unknown). Further studies are required to confirm the involvement of the putative genes in the bentazone reaction by comparing their expression levels between bentazone-tolerant and bentazone-sensitive plants. Therefore, the results of this study can be used for marker-assisted selection in programs for the breeding of herbicide-tolerant soybeans.

Soybean (Glycine max (L.) Merr.) is one of the most economically important crops in the world due to its nutritional value. To optimize soybean growth and yield, a wide range of commercial herbicides intended for weed control in crops are used. Although the herbicides used are selective, they can still cause oxidative stress and disturb photosynthetic reactions in soybean crops. In this work, the influence of commercial selective herbicides for weed control on the photosynthetic efficiency and antioxidative response of two soybean cultivars was investigated. The parameters describing the photosynthetic performance of soybean were derived by measuring in vivo chlorophyll a fluorescence while the antioxidative response was evaluated by determining activities of the selected antioxidative enzymes and parameters of oxidative stress at different development stages. The results showed a different response of the two soybean cultivars to herbicide treatment. Both investigated soybean cultivars showed that herbicide treatment did not cause oxidative damage. However, they revealed different adaptation mechanisms of photosynthetic apparatus. A negative impact of herbicide application was observed mainly on the electron transport chain in both varieties.

A small low-power humidifier with a simple programmable on/off switch was used as a pulsed ultrasound generator. Using this tool, a novel sonochemiluminescence (SCL) method was developed to determine bentazone. To the best of our knowledge, no chemiluminescence method has been proposed to determine this pesticide. Only five studies have been proposed for SCL quantitative applications so far. Therefore, revealing new aspects of SCL promises to develop analytical methods for the quantitative determination of different substances. A molecularly imprinted polymerized high internal phase emulsion (MIP-polyHIPE) was synthesized, bentazone separated from aqueous solutions, and pre-concentrated by the MIP-polyHIPE foam. The adsorption of bentazone on the MIP-polyHIPE adsorbent was theoretically studied by density functional theory through molecular dynamics simulation. Both experimental and simulation results indicated removal and pre-concentration of bentazone by the MIP-polyHIPE adsorbent. Using the proposed SCL method and without pre-concentration process, a linear dynamic range (LDR) of 2.5 × 10−7–5.0 × 10−5 mol L−1 and a limit of detection (LOD) of 8.4 × 10−8 mol L−1 were obtained for bentazone with a relative standard deviation of 2.64%. The LDR and LOD were improved to 2.6 × 10−9–2.0 × 10–7 mol L−1 and 8.8 × 10−10 mol L−1, respectively, using MIP-polyHIPE adsorbents. The method's application was evaluated by removing and pre-concentration of bentazone from water samples, including well, river, and tap water. The results showed that the pre-concentration factor and recovery percentages were 113–131 times and 93–106%, respectively, using the MIP-polyHIPE absorbent. [ABSTRACT FROM AUTHOR]

Bentazone is a widely used post-emergence herbicide, while no data was available on its concentrations in tap water from China and in urine among the general population. It was determined in the source (Wuhan section of the Yangtze River watershed), treated, and tap water (n = 20, 20, and 170, respectively) in different seasons (2019) in Wuhan, central China. Also, urine samples (n = 38) collected from healthy adults in Wuhan (September 2020) were analyzed to characterize its urinary concentration. Bentazone was detected in all the source and treated water samples. Its concentrations in the source water in July were higher than those in February (median: 17.9 ng/L vs. 2.86 ng/L) (p < 0.05). It cannot be removed efficiently (27.8–27.9%) by conventional drinking water treatment using NaClO, but it can be efficiently removed by using chlorine dioxide or ozone combined with activated carbon. Bentazone was frequently detected (detection frequency: 96.3%) in 160 tap water samples (underwent conventional treatment) (median: 1.95 ng/L, range: <0.02–47.0 ng/L), while it was not detectable in tap water samples that underwent ozone combined with activated carbon. Seasonal variations were found, with the lowest median concentration (ng/L) in April (0.46) and the highest in July (17.6). In addition, bentazone was frequently (92.1%) detected in human urine samples (median: 0.02 ng/mL; range: < 0.01–0.11 ng/mL). The estimated daily intake of bentazone based on its median concentration in tap water (0.04 ng/kg-body weight [bw]/day) accounted for approximately 8% of that based on the median urinary concentration (0.48 ng/kg-bw/day). This is the first time to characterize its occurrence in drinking water from China and its occurrence in the urine of the general population. [ABSTRACT FROM AUTHOR]

The usefulness of 3 herbicides and flame weeding in lemon balm sown directly into the field was assessed in a two-year experiment. Glufosinate-ammonium (600 g·ha-1) and flame weeding (90 kg propane·ha-1) were applied 12-13 days after lemon balm sowing, i.e. shortly after weed emergence and 4 days before crop emergence. Bentazon (960 g·ha-1) and fluazifop-P-butyl (150 g·ha-1) were sprayed approximately 3 weeks after sowing, during the emergence of lemon balm, and when the weeds were in the cotyledon -- 2-4 true leaves stage. All of the studied weed control methods significantly reduced the number and fresh weight of weeds growing 4 weeks after lemon balm sowing. The most effective method was spraying with glufosinate-ammonium, which controlled 69-76% of weeds. The efficiency of flame weeding was slightly lower. Bentazon caused slight, temporary chlorosis of some lemon balm cotyledons. Content of essential oil (1.9-2.1%), its composition and content of rosmarinic acid (2.08-2.44%) in lemon balm leaves, as well as content of total nitrogen (2.18-2.55%), phosphorus (0.30-0.32%), potassium (2.94-3.22%), calcium (1.02-1.60%), and magnesium (0.30-0.32%) in lemon balm raw material were independent of the weeding method. Content of essential oil, phosphorus, potassium and calcium were significantly higher in the dryer year. Studied weed control methods proved useful in the cultivation of lemon balm from direct sowing into the field. Methods with total action (flaming and glufosinate-ammonium) were more effective than those with selective herbicides (bentazon and fluazifop-P-butyl). [ABSTRACT FROM AUTHOR]

Yellow nutsedge (Cyperus esculentus) is a troublesome weed. It reproduces and spreads mainly via tubers, but also viable seeds are produced. The seeds are very small and have little resources stored. The seedlings are very fragile and look like grasses (poaceae). We hypothesized that C. esculentus plants originating from seeds are more susceptible to herbicides than plants originating from tubers. Cyperus esculentus plants grown from seeds in the greenhouse were treated with glyphosate, bentazone, bromoxynil, pelargonic acid and clethodim. Herbicide efficacy was rated and produced tubers were counted. None of the treatments achieved full control. Four weeks after application a growth reduction of 84% was observed in the glyphosate treatment, whereas bentazone reduced growth by 34% compared to the control. In the other treatments, growth reduction was < 15%. In the glyphosate and bentazone treatment, considerably fewer tubers were produced than in the control. Concluding, we could not confirm our hypothesis. Already 6 weeks after germination seedlings were well developed, tolerant to the sprayed herbicides, except for glyphosate and bentazone, and produced tubers. This implies, that already after a short time Cyperus esculentus stands originating from seeds pose the same problems as the ones originating from tubers.

The usefulness of 3 herbicides and flame weeding in lemon balm sown directly into the field was assessed in a two-year experiment. Glufosinate-ammonium (600 g∙ha–1) and flame weeding (90 kg propane∙ha–1) were applied 12–13 days after lemon balm sowing, i.e. shortly after weed emergence and 4 days before crop emergence. Bentazon (960 g∙ha–1) and fluazifop-P-butyl (150 g∙ha–1) were sprayed approximately 3 weeks after sowing, during the emergence of lemon balm, and when the weeds were in the cotyledon – 2–4 true leaves stage. All of the studied weed control methods significantly reduced the number and fresh weight of weeds growing 4 weeks after lemon balm sowing. The most effective method was spraying with glufosinate-ammonium, which controlled 69–76% of weeds. The efficiency of flame weeding was slightly lower. Bentazon caused slight, temporary chlorosis of some lemon balm cotyledons. Content of essential oil (1.9–2.1%), its composition and content of rosmarinic acid (2.08–2.44%) in lemon balm leaves, as well as content of total nitrogen (2.18–2.55%), phosphorus (0.30–0.32%), potassium (2.94–3.22%), calcium (1.02–1.60%), and magnesium (0.30–0.32%) in lemon balm raw material were independent of the weeding method. Content of essential oil, phosphorus, potassium and calcium were significantly higher in the dryer year. Studied weed control methods proved useful in the cultivation of lemon balm from direct sowing into the field. Methods with total action (flaming and glufosinate-ammonium) were more effective than those with selective herbicides (bentazon and fluazifop-P-butyl).

Introduction: Bentazon (BNTZ) is a selective contact herbicide widely used to control field weeds for crop production. Excessive use of BNTZ leads to its accumulation in soils and crops, becoming an environmental contaminant. Therefore, investigation of the mechanisms for BNTZ detoxification and degradation in crops is fundamentally important to reduce crop contamination and ensure food safety., Objectives: This study aims to elucidate the mechanism of detoxification and degradation pathways of the BNTZ complex in rice by creating transgenic lines expressing a rice ATP-binding cassette (OsABC) transporter gene through genetic engineering techniques combined with chemical analytical techniques and metabolomics approaches., Methods: We established the rice transgenic lines overexpressing (OE) a rice OsABC transporter and its knockout lines by CRISPR-Cas9 to characterize the gene function and measured the accumulation of BNTZ residues in rice. The metabolites of BNTZ were characterized by LC/Q-TOF-HRMS/MS (Liquid chromatography/time of flight-high resolution mass spectrometry)., Results: Overexpression of OsABC significantly conferred rice resistance to BNTZ toxicity by increasing plant elongation, dry weight, and chlorophyll content, and significantly reducing cell membrane damage and BNTZ accumulation in rice tissues. Six different metabolites and ten conjugates were well defined in chemical structures. The reduced BNTZ levels and degradation products in the grains of the OE lines supported the robust activity of the OsABC gene function. Using UPLC-Q-TOF/MS, we further identified accumulated basic metabolites of various carbohydrates, amino acids, hormones, and flavonoids, and found that these metabolites involved in BNTZ degradation were increased more in OE lines than in wild-type (WT) rice., Conclusions: Our work demonstrates that the OsABC transporter plays a critical role in regulating the mobility and degradative metabolism of BNTZ in rice, thus revealing a regulatory mechanism underlying rice resistance to BNTZ toxicity and adaptation to the environmental stress., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Production and hosting by Elsevier B.V.)

In Japan, the spread of morning glory (Ipomoea spp.) in soybean fields has become a serious issue. To establish a control approach for Ipomoea species, this study considered the optimal system combining cultural and chemical control methods. Field experiments were conducted for 3 years to investigate the effects of no‐tillage compared with tillage seeding in narrow‐row soybean and of application timing of selective post‐emergence herbicides bentazone and fluthiacet‐methyl. The cumulative emergence of entireleaf morning glory (Ipomoea hederacea [L.] Jacq. var. integriuscula A. Gray) in no‐tillage was 25–79% of that in tillage, and the initial growth was suppressed. In no‐tillage, the dry matter weight of I. hederacea var. integriuscula was suppressed compared to tillage methods. However, in no‐tillage, initial soybean growth was inferior, and reduction of the relative photosynthetic photon flux density (RPPFD) in the soybean canopy was delayed. A combination of selective post‐emergence herbicide applications at the second and fourth trifoliate leaf stages (TLS) of soybean was most effective in I. hederacea var. integriuscula suppression. The initial growth of soybean greatly fluctuated yearly, and the period when the RPPFD became less than 50% varied at the fourth through seventh TLS. Therefore, if the initial soybean growth is good, the end of the required period for weed control can be defined as the fourth TLS. No‐tillage cultivation combined with management to promote soybean growth, such as adequate soil moisture control by subirrigation systems, may be effective in controlling I. hederacea var. Integriuscula. [ABSTRACT FROM AUTHOR]

Bentazone (BEZ) is one of the utmost selective problematic contact-past herbicide with high toxicity for humans owing to feasible contamination of surface and ground water. In this work, an electrochemical sensor has been developed for the sensitive detection of BEZ, based on hierarchically porous three-dimensional (3D) carbon superstructures (CS)–modified electrodes. The CSs (namely, CSHEX, CSPY, CSACN, and CSNOS) were prepared by the pyrolysis process from organic porous polyacrylonitrile (PAN) superstructure particles (namely, PANHEX, PANPY, PANACN, and PANNOS) obtained by free radical polymerization method using different solvents (hexane, pyridine, acetonitrile, and also no solvent). The assembly with the working electrode of CSs causes the electrocatalytic BEZ oxidation by rapid electron transfer compared to the PAN superstructures and bare electrodes. Intriguingly, compared to all electrodes, CSHEX-modified electrode showed the superior electrochemical detection of BEZ at a working potential of 0.99 V (vs. Ag/AgCl), very low detection limit (0.002 μM), wide dynamic linear range (0.03 to 200 μM), high sensitivity (9.95 μA μM−1 cm−2), and excellent reliability. The advanced sensors displayed an intensification of oxidation peak current of BEZ with high selectivity, remarkable sensitivity, and reproducibility for BEZ detection and received satisfactory outcomes designating the application of sensors for the determination of BEZ in river water samples. [ABSTRACT FROM AUTHOR]

Pesticides are the most perilous organic compounds that are of major human health concern. The hazardous pesticides such as bentazone (BTZN) and mexacarbate (MCBT) which badly cause the environmental pollution and pose lethal impacts on human health. In an effort to develop a highly efficient, reliable and sensitive electrochemical sensor, the novel CuO nanostructures were synthesized through easy and green aqueous chemical growth procedure and used as sensitive probe for the simultaneous determination of bentazone and mexacarbate pesticides. The prepared material was used as conductive and catalytic tool for the modification of glassy carbon electrode (GCE). The exquisite CuO nanostructures were characterized by FTIR, FE-SEM, XRD, EDS, zeta sizer and zeta potential to reveal the functionalities, morphological texture, crystallinity, size and existing charge on the surface of nanostructures. The conductive nature and charge transfer kinetics of CuO/GCE was explored through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Under the optimized parameters, the sensitive and reliable simultaneous determination of two pesticides was carried out via CV and DPV that exhibited fluent determination process. The Ipa response was linearly proportional to the concentration of pesticides with low LOD and LOQ observed as (0.008 and 0.026 µM) for bentazone and (0.0015 and 0.004 µM) for mexacarbate, which is lower than the permissible limit set by US Health Advisory Level. Moreover, the developed sensor manifested tunable reusability, stability, and selectivity for both analytes. The proposed method is a reliable step towards the on-site detection of pesticides in various resources. [ABSTRACT FROM AUTHOR]

Herbicides are hazardous organic pollutants that contribute to the risk of environmental contamination. The aim of this work was to investigate the synergistic effect of silver (Ag) and gold (Au) bimetallic nanoparticles deposited on palygorskite (PAL) in the presence of TiO2 for photodegradation of bentazone (BTZ) herbicide under UV light. Ag and Au@Ag nanoparticles exhibited an average size below 75 nm and surface charge values less than − 30 mV. UV-Vis spectroscopy indicates the formation of core@shell bimetallic nanoparticles. XRD results showed the interactions between the NPs and the palygorskite structure. SEM images clearly illustrate the presence of small spherical particles distributed in the clay fibers. The control of the size and distribution of the nanoparticles played an important role in the properties of the composites. The degradation of the herbicide BTZ showed that nanoparticles, clay, and only TiO2 did not produce satisfactory results; however, when Ag-Pal and Au@Ag-Pal were in the presence of the TiO2, the degradation was efficient. The best photodegradative system was Au@Ag-Pal+TiO2, which was maintained after the third cycle. The bentazone photodegradation using Au@Ag-PAL+TiO2 exhibited toxicity against Artemia salina. Therefore, Au@Ag-PAL+TiO2 photocatalyst showed that the synergy of bimetallic nanoparticles deposited on clay for enhanced photodegradation activity of bentazone herbicide. [ABSTRACT FROM AUTHOR]

Abstract In accordance with Article 6 of Regulation (EC) No 396/2005, the applicant BASF SE submitted a request to the competent national authority in the Netherlands to modify the existing maximum residue levels (MRLs) for bentazone in beans and peas with and without pods. The data submitted in support of the request were found to be sufficient to derive MRL proposals for peas with pods. Results from the residue trials indicated that there is no need to modify the existing MRLs for beans with pods, beans without pods and peas without pods. Adequate analytical methods for enforcement are available to control the residues of bentazone and its metabolites in the commodity under consideration at the validated limit of quantification (LOQ) of 0.01 mg/kg. EFSA concluded that the proposed use of bentazone on peas with pods will not result in a consumer exposure exceeding the toxicological reference values and therefore is unlikely to pose a risk to consumers’ health for parent bentazone. The risk assessment however is indicative and affected by additional, non‐standard uncertainties resulting from the insufficient information related to the toxicological properties for 6‐hydroxy‐bentazone in the wheat metabolism study.

The aim of the study is to determine the effects of Bentagran on growth and oxidative effects to Chlorella vulgaris and Arthrospira platensis and to evaluate the herbicide toxicity on primary producers of aquatic ecosystems. The decrease in both biomass accumulation and chlorophyll-a content in a dose-dependent manner were observed in both organisms exposed to different Bentagran concentrations (for C. vulgaris 60–960 µg mL−1; for A. platensis 100–800 µg mL−1) during 7 days. SOD activity increases significantly in Chlorella vulgaris and Arthrospira platensis at concentrations of 480 and 200 ug mL−1, respectively. Although there was no significant change in APX (ascorbate peroxidase) activity in C. vulgaris, the APX activity decreased at 400 and 600 µg mL−1 concentrations in A. platensis. While the GR (glutathione reductase) activity increased at 960 µg mL−1 concentration in C. vulgaris, it also showed increases at 100, 200 and 400 μg mL−1 concentrations, but it decreased at 600 µg mL−1 concentration in A. platensis. MDA (malondialdehyde) and proline amounts decreased only at the concentration of 960 µg mL−1, while H2O2 didn't change compared to control. Total MDA, H2O2 (hydrogen peroxide) and proline amounts did not show significant change compared to control. It is found that the effects of Bentagran on growth and antioxidant parameters are diverse at different concentrations and species, and this can be attributed to the different reactive oxygen species (ROS) production ability in these species. The aim of the study is to determine the effects of Bentagran on growth and oxidative effects to Chlorella vulgaris and Arthrospira platensis and to evaluate the herbicide toxicity on primary producers of aquatic ecosystems. Bentagran effected to the biomass accumulation and chlorophyll-a content in a dose-dependent manner and it caused the oxidative stress in both organism. [ABSTRACT FROM AUTHOR]

In accordance with Article 6 of Regulation (EC) No 396/2005, the applicant BASF SE submitted a request to the competent national authority in the Netherlands to modify the existing maximum residue levels (MRLs) for bentazone in beans and peas with and without pods. The data submitted in support of the request were found to be sufficient to derive MRL proposals for peas with pods. Results from the residue trials indicated that there is no need to modify the existing MRLs for beans with pods, beans without pods and peas without pods. Adequate analytical methods for enforcement are available to control the residues of bentazone and its metabolites in the commodity under consideration at the validated limit of quantification (LOQ) of 0.01 mg/kg. EFSA concluded that the proposed use of bentazone on peas with pods will not result in a consumer exposure exceeding the toxicological reference values and therefore is unlikely to pose a risk to consumers' health for parent bentazone. The risk assessment however is indicative and affected by additional, non-standard uncertainties resulting from the insufficient information related to the toxicological properties for 6-hydroxy-bentazone in the wheat metabolism study. [ABSTRACT FROM AUTHOR]

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bentazone is a herbicide, which is frequently detected in groundwater due to its mobility and persistence in aquifers. Groundwater is used as a drinking water source all over the world, and sustainable methods to remove pesticides at low concentrations are urgently needed since pesticide contaminations can adversely affect human health. The aim of this study was to investigate whether microbial bentazone degradation was associated with methane oxidation in full-scale drinking water treatment plants. To this end, we investigated bentazone biodegradation in microcosms with water and filter material from rapid sand filters, or biomass from aeration systems, and we investigated the statistical relation between the presence of methane and bentazone in groundwater abstraction wells. An array of evidence supported an association between bentazone degradation and methane oxidation in the biological treatment process. The biodegradation potential of bentazone was associated with the presence of methane in the raw water at 14 different water works. In contrast, no association was observed with any of the other investigated inorganic energy sources, e.g., ammonium. Addition of acetylene inhibited methane oxidation and the bentazone degradation in filter material from two investigated waterworks. Biomass from the aeration tanks degraded bentazone, but only while oxidizing methane. Bentazone removal rates and methane removal rates correlated significantly across all the experiments with biomass or filter material, with an overall transformation yield of 15 ± 1 × 10–5 moleBTZ/moleCH4. This demonstrated that the bentazone degradation was conducted by the same type of process in all the investigated communities, governed by methane oxidation. Furthermore, based on more than 10.000 water analyses from waterworks abstraction wells in Denmark, bentazone was detected significantly less frequent in wells with high methane concentrations (>1 mg/L) than in wells without methane. This suggests that biological treatment of bentazone contamination in drinking water may be achieved using methanotrophs.

Bentazone is one of the toxic insecticides used to control forest tent caterpillar moths, boll weevils, gypsy moths, and other types of moths in various field crops. We report the efficacy of biochar prepared from the Azardirachta Indica waste biomass as adsorbent for removal of Bentazone. Biochar material was prepared by pyrolysis process under limited oxygen conditions. Biochar material was characterized by proximate and ultimate analysis, SEM analysis, FTIR analysis and TG/DTA analyses. The Bentazone adsorption capacity by biochar from aqueous solutions was assessed. Effect of time, adsorbent dosage, insecticide concentration and pH on the adsorption characteristics of the biochar were evaluated. Adsorption parameters were obtained at equilibrium contact time of 150 min, with biochar dosage of 0.5 g at pH 8. From the optimization studies, desirability of 0.952 was obtained with response (adsorption uptake) of 79.40 mg/g, for initial concentration of insecticide (50 mg/L), adsorbent dosage (0.448 g), time 30.0 min and pH 2. The adsorption isotherm data for the removal of Bentazone fitted well with the Freundlich isotherm. This study indicates that the biochar produced from the bark of Azardirachta Indica biomass could be employed as a potential adsorbent for removal of synthetic organic pollutants from the water streams. [ABSTRACT FROM AUTHOR]

Under rice-rapeseed rotation in the Yangzi River Basin, risk of rice herbicide residues on rapeseed production should be evaluate for selection of herbicide-tolerant rapeseed. Thus 19 rapeseed varieties were evaluated under pyrazosulfuron, pretilachlor, bentazone and cyhalofop herbicides stresses. Rapeseed traits were investigated on seed germination rate, plant height, maximum root length, fresh weight aboveground, fresh weight of roots, dry weight aboveground and root dry weight. Results showed that, under herbicide stresses, the tolerance coefficients of different genotype were significantly different. By cluster analysis, varieties were selected with relatively strong tolerance to different herbicides. It showed that comprehensive evaluation of herbicide tolerance was effective on rapeseed by integration of principal component analysis, subordinative function value and clustering analysis, which could avoid bias and instability of single index analysis. It suggested a practical selecting method for rapeseed as succession crop after rice according to actual use of herbicides in rice plantation. [ABSTRACT FROM AUTHOR]

Necessity of having simple selective and robust methods for the analysis of environmentally relevant chemicals stimulates the development of new approaches to material preparation. Electrochemical sensing using electroactive substrates has proved efficient in the analysis of a wide range of pesticides and is widely used as a routine analytical method. Recently, mixed oxides showed promising electrocatalytic activity toward hazardous substrates. Prevalence of wet chemical methods in the synthesis of mixed oxides creates a methodological obstacle and inconvenience for their wide utilization. In this work we challenged the common preparation of mixed oxides with simple powder mixing and developed an electrode for bentazone detection with satisfactory detection limit (0.4 μM), recovery rate (≈104%), and a broad linearity range (1–45 μM). The proposed modified carbon paste electrode is highly selective and can be used for determination of bentazone in presence of interfering ions in water samples. [Display omitted] • Zero-waste mixing of commercially available oxide provided electroactive material. • PXRD and XPS confirmed significant interaction of two oxide phases. • Mixed oxides served an excellent CPE-modifier for bentazon detection. • Developed pesticide-sensor demonstrated good sensitivity, selectivity and stability over time. • Old-fashion sensor preparation will be upgraded to mechanochemical processing. [ABSTRACT FROM AUTHOR]

Wetlands are among the most threatened ecosystems on the planet and pollution is a major factor causing the decline of wetland biodiversity. Despite the increasing use of pesticides, their fate and effects on freshwater reptiles remain largely unknown. We studied the European pond turtle (Emys orbicularis), a long-lived species at risk with a high exposure potential to pesticides. Between 2018 and 2020, we measured 29 pesticides and metabolites in 408 blood samples of turtles from two populations in the Camargue wetland (France). We were able to quantify 24 compounds and at least one pesticide or one degradation product in 62.5% of samples. Pesticide occurrences and concentrations were low, except for a herbicide widely used in rice cultivation and locally detected in water: bentazone that reached high blood concentrations in E. orbicularis. The occurrence and the concentration of pesticides in E. orbicularis blood depended mainly on the site and the sampling date in relation to pesticide application. Individual characteristics (sex, age, body condition) did not explain the occurrence or the concentration of pesticides found in turtle blood. Assessing the exposure of aquatic wildlife to a cocktail of currently-used pesticides is a first and crucial step before studying their effects at the individual and population levels. [Display omitted] • Turtles from rice-growing drainage area were frequently contaminated by pesticides. • Pesticide occurrence and concentrations were linked to the year and day of sampling. • Bentazone was the most detected pesticide without evidence for bioaccumulation. • Individual characteristics did not influence occurrence nor pesticide concentration. [ABSTRACT FROM AUTHOR]

Bentazone is classified as a moderately hazardous (class II) herbicide by the World Health Organization. A 53-year-old Korean woman was transferred to the emergency department after a suicide attempt using approximately 500 mL of bentazone one hour prior to admission. Upon admission, she was alert and tachycardia of 125/min was observed. She was treated with gastric lavage and activated charcoal, during which she experienced diarrhea. Two hours after bentazone ingestion, cardiac arrest and muscle rigidity throughout the body occurred. Cardiopulmonary resuscitation was immediately started. Endotracheal intubation after administration of a muscle relaxant (succinylcholine) was unsuccessful because of temporomandibular joint muscle rigidity. Surgical cricothyroidotomy was performed by the emergency physician, but the patient was not resuscitated. For cardiac arrest patients with muscle rigidity caused by bentazone overdose, endotracheal intubation may be challenging because of muscle rigidity, despite appropriate use of muscle relaxants. Early surgical cricothyroidotomy may be the preferred method of airway management in these patients.

In this study, the photocatalyst of TiO2/Fe2O3 based on clinoptilolite natural zeolite was synthesized by co-precipitation method and its function in degradation of Bentazone, as one of the most widely used herbicides in agriculture, was evaluated. The effect of process parameters simultaneously including pollutant concentration (1-40 mg/l), pH (4-10) and hydrogen peroxide concentration (25-100 mg/l) on photocatalytic degradation efficiency of Bentazone was investigated using design of experiments in response surface methodology. Synthesized photocatalyst was characterized by XRD, XRF, FT-IR, FE-SEM and EDX analyses. The results of XRD, FT-IR, and EDX confirmed the presence of TiO2 and Fe2O3 nanoparticles on the surface of clinoptilolite. The FE-SEM results confirmed the deposition of TiO2/Fe2O3 on the surface of clinoptilolite zeolite and also the approximate particle size of TiO2/Fe2O3 was 52 nm. According to XRF results, the synthesized nanoparticles had Fe3+/TiO2 optimal molar ratio of 0.06. The results showed that Bentazone concentration, pH and hydrogen peroxide concentration were the most effective factors on photocatalytic degradation efficiency of Bentazone, respectively. According to the experimental data at optimal conditions (pH, pollutant concentration and hydrogen peroxide concentration are 10, 10 mg/l and 50 mg/l, respectively), degradation efficiency of Bentazone was obtained 97% and the degradation efficiency was 78% at maximum concentration of pollutant (40 mg/l). This study showed that the synthesized photocatalyst has acceptable efficiency for degradation of non-biodegradable pollutant and removal pesticides from contaminated water.

Abstract In accordance with Article 6 of Regulation (EC) No 396/2005, the applicant BASF SE submitted an application to the competent national authority in the Netherlands to modify the existing maximum residue levels (MRLs) for bentazone in soyabeans and poppy seeds. The data submitted in support of the request were found to be sufficient to derive MRL proposals for both commodities. Adequate analytical methods for enforcement are available to control the residues of bentazone and its metabolites in plant matrices under consideration. The studies requested by EFSA in the framework of the peer review to address the toxicological properties of metabolite 6‐hydroxy‐bentazone were only partially provided. Instead of studies investigating the general toxicity of this metabolite, the applicant provided an argumentation to justify read‐across from the available information on parent bentazone and 8‐hydroxy‐bentazone. EFSA did not agree with the provided reasoning for read‐across. Therefore, the EMS asked EFSA to continue the assessment despite the data gap. EFSA performed an indicative short‐term and long‐term dietary risk assessment; the calculated dietary exposure was well below the toxicological reference values. The risk assessment however is affected by additional, non‐standard uncertainties resulting from data gap related to the toxicological properties for 6‐hydroxy‐bentazone.

Abstract The applicant BASF SE submitted a request to the competent national authority in the Netherlands to evaluate the confirmatory data that were identified for bentazone in the framework of the maximum residue level (MRL) review under Article 12 of Regulation (EC) No 396/2005 as not available. To address the data gaps, a new livestock feeding study and storage stability data for bentazone and 6‐hydroxy bentazone in animal matrices were submitted. To address the data gap for potatoes, adjusted less critical good agricultural practices (GAPs) were reported and supporting residue data were provided. The data gap related to analytical methods in fat and herbal infusions were addressed in the framework of the peer review. The data gap for residue trials on leek has not been addressed. Further confirmation from the applicant/Member States are needed for the clarification of the GAP for herbal infusions. Based on the information submitted in support of the confirmatory data request, the existing EU MRLs for bentazone need to be modified for potato and leek, for swine fat and kidney and for bovine, equine, goat and sheep fat, liver and milk. The consumer risk assessment performed in the MRL review was updated, using new toxicological reference values derived by the peer review. No consumer intake concerns were identified.

Potato (Solanum tuberosum), an important food crop worldwide, is threatened by broadleaf weeds. Bentazone is an effective herbicide for controlling weeds; however, as a photosynthesis inhibitor, it can also affect potato plants. Therefore, screening potato seedlings for bentazone resistance and determining the genes involved is essential. Herein, we selected potato varieties with tolerance and sensitivity to bentazone. The photosynthetic rate of sensitive plants was notably affected by bentazone application, whereas the tolerant plants showed a significantly higher photosynthetic rate. We observed 95.7% bentazone degradation within 24 d after application in the tolerant plants. Transcriptome sequencing revealed that the numbers of differentially expressed genes (DEGs) between the tolerant and sensitive potato seedlings were 2703 and 11,024 before and after bentazone application, respectively. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that the majority of DEGs were enriched in metabolic pathways, biosynthesis of secondary metals, carbon metabolism, glutathione metabolism, and photosynthesis. Polyphenol oxidase (PPO), flavonoid 3′,5′-methyltransferase-like (AOMT3), ribulose bisphosphate carboxylase small chain C (RBCS-C), and chalcone synthase 2 (CHS2) were identified as candidates contributing to bentazone tolerance. These results provide a theoretical basis for selecting potato stress-resistant resources in the future.

Bentazone is one of the most problematic pesticides polluting groundwater resources. It is on the list of pesticides that are mandatory to analyze at water work controls. The current pesticide measuring approach includes manual water sampling and time-consuming chromatographical quantification of the bentazone content at centralized laboratories. Here, we report the use of an electrochemical approach for analytical determination of bentazone that takes 10 s. The electrochemical electrodes were manually screen printed, resulting in the low-cost fabrication of the sensors. The current response was linearly proportional to the bentazone concentration with a R2 ~ 0.999. We demonstrated a sensitivity of 0.0987 μA/μM and a limit of detection of 0.034 μM, which is below the U.S. Health Advisory level. Furthermore, the sensors have proved to be reusable and stable with a drop of only 2% after 15 times reuse. The sensors have been applied to successfully quantify bentazone spiked in real groundwater and lake water. The sensing method presented here is a step towards on-site application of electrochemical detection of pesticides in water sources. Unlabelled Image • Selective method for instant quantification of bentazone in water with detection limit below the U.S. Health Advisory level. • Simple in-house fabrication of low-cost sensors for bentazone detection. • Sensors can be deployed in the field as they are reusable and can measure with high reproducibility. • Selective bentazone detection was possible despite the presence of other interfering chemicals. • Sensors were applied for detection of bentazone in real ground water and lake water with high precision. [ABSTRACT FROM AUTHOR]

Superfine powdered activated carbon (SPAC) of micron to submicron particle size is produced by micro-milling of conventionally sized powdered activated carbon. SPAC has attracted attention because of its high adsorption capacity; however, milling to the submicron particle size range lowers its adsorption capacity. Here, we found that this decrease of adsorption capacity was due to the introduction of oxygen/hydrogen-containing functional groups into the graphene structure of the carbon from water during the milling, causing it to become less hydrophobic. This finding was supported by three analyses of SPAC particles before and after milling: 1) elemental analysis revealed increased oxygen and hydrogen content, 2) Boehm titration analysis revealed increased amounts of acidic functional groups, including carboxylic and phenolic hydroxyl groups, and 3) Fourier-transform infrared spectroscopy showed increased peaks at 1200, 1580, and 3400 cm−1, confirming the presence of those groups. Dissolved oxygen concentration did not strongly affect the increase of oxygen content in SPAC, and no evidence was found for hydroxyl radical production during micro-milling, suggesting that a mechanochemical reaction underlies the increase in oxygen/hydrogen-containing functional groups. An increase in 18O content in the SPAC particles after milling in water-18O indicated that the oxygen in the functional groups originated from the surrounding water. Graphical abstract Image 1 Highlights • Long-time milling of activated carbon decreases adsorption capacity. • It is due to decrease of hydrophobicity at activated carbon particle surface. • Oxygen/hydrogen-containing functional groups are introduced into graphene structure. • Oxygen in the functional groups originates from the surrounding water. • Oxidation of carbon by DO plays a minor role and no other oxidants are formed. [ABSTRACT FROM AUTHOR]

Hydrolysis and photolysis of bentazone in abiotic aqueous solutions were examined under laboratory conditions. Hydrolysis was studied in different buffer solutions (pH 4.0 ± 0.1, 7.0 ± 0.1, and 9.0 ± 0.1), at different temperatures (15 °C ± 2 °C, 25 °C ± 2 °C, 35 °C ± 2 °C, and 45 °C ± 2 °C), and at different Fe3+ concentrations (1, 5, and 10 mg/L). Photolysis was assessed in different buffer solutions and at different solvent (methanol and ethyl acetate) concentrations (10%, 20%, and 30%) or Fe3+ (1, 5, and 10 mg/L) concentrations and under mercury or xenon light irradiation. Hydrolysis half-lives ranged 46–99 days at three different conditions. Photolysis half-lives ranged 2.3–7.5 h in three different conditions under mercury and xenon irradiation. Hydrolysis and photolysis of bentazone were accelerated by both alkaline conditions and elevated temperatures, and solvents and Fe3+ strongly enhanced bentazone degradation. Photodecomposition was much faster under a mercury lamp than under a xenon lamp. N-methyl bentazone and 6-OH bentazone/8-OH bentazone were identified as degradation products using UPLC-Q-TOF-MS. The data generated from this study could be useful for risk assessment of pesticides in the environment. [ABSTRACT FROM AUTHOR]

Soybean is one of the most important crops widely used as food, feed, and industrial products. Weeds compete with the crops for light, nutrients, water, space, and other growth requirements, causing an average yield reduction of 37% in soybean. Bentazone is an herbicide that selectively kills broadleaf weeds by inhibiting photosynthesis. It is widespread in soybean-cultivating areas including genetically modified organism (GMO) and GMO-free regions all around the world. This herbicide carries a double-edged sword since it can also incur damage to crops upon application. The challenge, therefore, lies in the deliberate selection of bentazone-tolerant cultivars. We systematically analyzed several factors that affect the metabolism of bentazone in soybean, such as phenotypic and genotypic differences among soybean accessions, the time and method of application, the absorption and metabolism of bentazone in soybean, and the effects of effective application and cultivar selection on yield and crop injury. Furthermore, we recommend that further studies should be done in aid of discovering more tolerant soybean cultivars. We hope that our review will help farmers and soybean producers, as well as geneticists, in developing bentazone-tolerant soybean cultivars to improve the global yield of soybean crops as a response to the ever-dynamic food demand across the globe.

Pesticides are heavily used in agriculture to protect crops from diseases, insects, and weeds. However, only a fraction of the used pesticides reaches the target and the rest slips through the soil, causing the contamination of ground- and surface water resources. Given the emerging interest in the on-site detection of analytes that can replace traditional chromatographic techniques, alternative methods for pesticide measuring have recently encountered remarkable attention. This review gives a focused overview of the literature related to the electrochemical detection of selected pesticides. Here, we focus on the electrochemical detection of three important pesticides; glyphosate, lindane and bentazone using a variety of electrochemical detection techniques, electrode materials, electrolyte media, and sample matrix. The review summarizes the different electrochemical studies and provides an overview of the analytical performances reported such as; the limits of detection and linearity range. This article highlights the advancements in pesticide detection of the selected pesticides using electrochemical methods and point towards the challenges and needed efforts to achieve electrochemical detection suitable for on-site applications.

The herbicide bentazone is recalcitrant in aquifers and is therefore frequently detected in wells used for drinking water production. However, bentazone degradation has been observed in filter sand from a rapid sand filter at a waterworks with methane-rich groundwater. Here, the association between methane oxidation and removal of bentazone was investigated with a methanotrophic enrichment culture derived from methane-fed column reactors inoculated with that filter sand. Several independent lines of evidence obtained from microcosm experiments with the methanotrophic enrichment culture, tap water and bentazone at concentrations below 2 mg/L showed methanotrophic co-metabolic bentazone transformation: The culture removed 53% of the bentazone in 21 days in presence of 5 mg/L of methane, while only 31% was removed in absence of methane. Addition of acetylene inhibited methane oxidation and stopped bentazone removal. The presence of bentazone partly inhibited methane oxidation since the methane consumption rate was significantly lower at high (1 mg/L) than at low (1 μg/L) bentazone concentrations. The transformation yield of methane relative to bentazone normalized by their concentration ratio ranged from 58 to 158, well within the range for methanotrophic co-metabolic degradation of trace contaminants calculated from the literature, with normalized substrate preferences varying from 3 to 400. High-resolution mass spectrometry revealed formation of the transformation products (TPs) 6-OH, 8-OH, isopropyl-OH and di-OH-bentazone, with higher abundances of all TPs in the presence of methane. Overall, we found a suite of evidence all showing that bentazone was co-metabolically transformed to hydroxy-bentazone by a methanotrophic culture enriched from a rapid sand filter at a waterworks. [ABSTRACT FROM AUTHOR]

This study presents two cases of lethal bentazone poisonings, their clinical presentation, the course of the disease and the autopsy findings. The first is a 50-year-old male who had sprayed corn with a solution of bentazone and was admitted to the hospital with sweating, fever, nausea, vomiting of aqueous and hemorrhagic content, and bloody, watery stools. He was treated according to the symptoms including extracorporeal hemodialysis, but eventually suffered from multiorgan failure (acute respiratory failure, acute liver failure, coagulopathy, acute renal failure, metabolic acidosis, and gastrointestinal bleeding) and died 11.35 h after admittance. The cause of death was probable bentazone intoxication. The second case, also a male, aged 49 who committed suicide by ingesting a bentazone solution. He was transferred to the hospital prostrated and cyanotic and died 14.15 h after admittance despite all efforts by the hospital staff. The cause of death was acute bentazone intoxication. [ABSTRACT FROM AUTHOR]

A liquid chromatography-tandem mass spectrometry method with solid-phase extraction (SPE) was developed and validated for the detection and quantitation of bentazone and its two hydroxylated metabolites, 6-hydroxybentazone and 8-hydroxybentazone, in postmortem blood. Sample cleanup was performed using a hydrophilic-lipophilic balanced (HLB) SPE cartridge and then separated on a C18 LC column using a gradient elution of 0.1% formic acid in distilled water and 0.1% formic acid in methanol. The identification of bentazone and its hydroxylated metabolites was performed using tandem mass spectrometry with electrospray ionization in negative ion mode with selective reaction monitoring. The retention times of bentazone, 6-hydroxybentazone, 8-hydroxybentazone, and 2-methyl-4-chlorophenoxyacetic acid (MCPA, internal standard) appeared separately in the chromatogram. The matrix effect, recovery, and process efficiency of bentazone were 75.3%, 103.6% and 77.9%, respectively. In addition, good accuracy (88.2-110.5%), precision (0.5-7.5%, bias), and linearity (5-500ng/mL) were obtained with this method. The limit of detection (LOD) of bentazone, 6-hydroxybentazone, and 8-hydroxybentazone were 0.05, 0.5, and 0.5ng/mL, respectively. The method developed herein was applied to authentic samples from three fatal cases from 2016 for the determination of the corresponding bentazone and its metabolites levels. The concentration ranges of bentazone, 6-hydroxybentazone, and 8-hydroxybentazone in the heart blood from the three victims were 46.0-91.8, 4.2-6.2, and 0.2-0.6μg/mL, respectively. [ABSTRACT FROM AUTHOR]

Bentazone (BNTZ) is a selective and efficient herbicide used in crop production worldwide. However, the persistence of BNTZ residues in the environment has led to their increasing accumulation in farmland and crops, posing a high risk to human health. To evaluate its impact on crop growth and environmental safety, a comprehensive study was conducted on BNTZ toxicity, metabolic mechanism, and resultant pathways in rice. The rice growth was compromised to the treatment with BNTZ at 0.2-0.8 mg/L (529.95-1060.05 g a.i./ha), while the activities of enzymes including SOD, POD, CAT, GST, GT, and CYP450 were elevated under BNTZ stress. A genome-wide RNA-sequencing (RNA-Seq) was performed to dissect the variation of transcriptomes and metabolic mechanisms in rice exposed to BNTZ. The degradative pathways of BNTZ in rice are involved in glycosylation, hydrolysis, acetylation, and conjugation processes catalyzed by the enzymes. Our data provided evidence that helps understand the BNTZ metabolic and detoxic mechanisms.

Chlorophyll fluorescence is a type of radiation emitted by plants as unused part of energy absorbed from sunlight. Its intensity depends on many stress factors, nutrition, weather conditions etc. Methods based on chlorophyll fluorescence measurement have potential to be perspective for the assessment of herbicide efficacy, phytotoxicity or stress influence. Two fluorometers (FluorCam and handy FluorPen) were used for measurements in laboratory experiments in 2007–2009. Herbicide Basagran super with active ingredient bentazone (480 g.l−1) was tested using a parameter called ‚Quantum yield of fluorescence‘ (QY) in three different doses: the registered dose 2.0 l.ha−1 (100%) and lower doses 1.5 l.ha−1 (75%) and 1.0 l.ha−1 (50%). Treated experimental plants of redroot pigweed (Amaranthus retroflexus L.) were measured in 0, 1, 2, 3, 6, 9 and 15 days after treatment and the results were compared with subjective assessment (estimation) and growth parameters. The obtained results showed that the effect of bentazone measured by both devices was statistically significantly different from untreated control. We can also detect herbicide effect earlier by QY measurement than by other methods. Different doses showed significant differences 15 days after treatment for dose 2.0 l.ha−1 in comparison with both reduced doses. The subjective assessment showed significant differences in all terms of measurement (1–15 days after application) except of the day of application. Regeneration of plants for which the youngest leaves were not treated by herbicide was observed for all doses. Difference of QY values between used devices was on average 0.119 (higher for FluorCam) but statistically insignificant.

The effect of spray liquid leaves coverage on efficacy of herbicides was investigated. Five nozzles sizes were used to reach different percentage coverage. The effect of leaves coverage on Elytrigia repens (L.) Desv. was evaluated using systemic herbicide (clethodim 240 g / l + surfactant) and the effect of leaves coverage on Chenopodium album L. and Galium aparine L. was evaluated using contact herbicides (bentazone 600 g / l and the mixture of bentazone 480 g / l + activator 150 g / l). No significant differences of the efficacy were observed between different percentages of leaves coverage in case of systemic herbicides. Vice versa the efficacy significantly increased with higher percentage of leaves coverage in case of contact herbicides.

A micronucleus test was run to investigate mutagenic potential of the herbicide GAL-57, a formulated mixture of bentazone and dicamba.The test was applied to mice of both sexes (strain: CRL: NMRI BR) and the herbicide (product) was administered by gavage at 2000 mg/kg rate, twice within 24 hs. Cyclophosphamide (positive control) was administered at 60 mg/kg, while distilled water as a solvent was negative control. The animals were sacrificed 24 hs after second treatment, their bone marrow cells isolated from femur, and effects evaluated.The data acquired showed that repeated treatment of mice with GAL-57 caused neither biological nor significant statistical increase in the number of micronuclei in treated animals. At the same time, the number of micronucleated polychromatic erythrocytes in the bone marrow of animals treated with cyclophosphamide (positive control) showed a significant statistical increase. The results suggest that the herbicide product tested did not show any mutagenic activity under the conditions of mouse micronucleus test.

Abstract The conclusions of the European Food Safety Authority (EFSA) following the peer review of the initial risk assessments carried out by the competent authority of the rapporteur Member State Netherlands, for the pesticide active substance bentazone are reported. The context of the peer review was that required by Commission Regulation (EU) No 1141/2010 as amended by Commission Implementing Regulation (EU) No 380/2013. The conclusions were reached on the basis of the evaluation of the representative uses of bentazone as a herbicide on a variety of crops in the EU. The reliable endpoints concluded as being appropriate for use in regulatory risk assessment, derived from the available studies and literature in the dossier peer reviewed, are presented. Missing information identified as being required by the regulatory framework is listed. Concerns are identified.