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Earthworms are ecosystem engineers, owed to their ability to modify the soil resources for other organisms through induction of important changes in the state of the biotic and abiotic soil components. They are very sensitive small invertebrate animals to agricultural pesticides, as well as the best soil pollution bioindicators. Thus, the present study aimed to assess the effects of an herbicide (Linuron) induced changes in major biochemical markers (the content of total protein, total carbohydrate, total lipid, and catalase activity) in Lumbricus terrestris. Statistical analysis of data revealed significant differences in the content of total proteins, lipids, and total carbohydrates, and no significant difference in catalase activity between control and Linurontreated L. terrestris over the three exposure periods (24 h, 48 h, and 72 h) and the three doses used (250 µg, 500 µg, and 1000 µg). Moreover, correlation coefficient analysis showed a positive correlation between protein and lipid contents (r = 0.50, r2 = 50%) during all three exposure periods. Conclusively, this study suggested the determined metabolites as a valuable tools in the environmental risk assessment, and the understanding of the process underlying Linuron induced oxidative stress in L. terrestris. [ABSTRACT FROM AUTHOR]

Pesticides are defined as chemical substances used to protect a variety of plants from parasite infestation. Due to their chemical structure, they have a long half-life and the capacity to form residues, and therefore many fruits can contain pesticide residues. Pesticide exposure may occur via inhalation, ingestion, or direct contact. The European Commission's directive restricts the use of pesticides and sets a residue limit of 0.1 μg/L. The aim of this study is to determine the impact of bacteria in the human gut microbiota on the biodegradation of commonly used pesticides. This study investigated the effects of five bacterial strains, namely Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae (K. pneumoniae), and Enterococcus faecalis (E. faecalis), isolated from neonatal rectal swab samples and, blood samples on the degradation of pesticides using liquid chromatography and mass spectrometry. (LC-MS). All bacteria resulted in significant pesticide degradation (p < 0.05). E. faecalis caused significantly more degradation than K. pneumoniae (p = 0.043). No significant difference was observed between the degradation rates of pesticides and other bacteria (p > 0.05). The results demonstrate that bacteria can be used to clean water and soil contaminated with pesticides. Therefore, we do not have information about possible mutations in DNA. This is the biggest limitation of this study. Therefore, our study data needs to be supported with study data including more strains and examining bacterial DNA with new generation sequencing methods.

Innovation in agriculture chemicals and delivery systems is essential for the production of food for sustainable development. Herein, natural polymers and agar-gelatin-derived controlled delivery devices for linuron herbicide to prevent environmental and health hazards. These hydrogels were designed by the graft-copolymerization reaction of poly(methacrylamide) [poly(MAAm)] on agar-gelatin for use as controlled-release formulations (CRF). Copolymers were characterized by Copolymers were characterized scanning electron micrographs (SEM), Atomic force microscopy (AFM), X-ray diffraction (XRD) Fourier transform infrared spectroscopy (FTIR), 13C-nuclear magnetic resonance (NMR), and thermogravimetric analysis -differential thermogravimetry (TGA-DTG) techniques. SEM shows the uneven surface morphology, and AFM showed a rough surface with an average roughness value of 137.50 nm in the polymeric matrix. The amorphous nature of the polymer was confirmed with XRD techniques. Grafting of the poly(MAAm) on the agar and gelatin was confirmed by FTIR and 13C NMR spectra. Agar-gelatin-cl-poly(MAAm) hydrogels absorbed water at 4.05 ± 0.32 g per gram, which is useful for soil water retention. Release of the linuron herbicide occurred in a controlled manner during 72 h of observations and followed non-Fickian diffusion mechanism. The slow release of the linuron from the hydrogel is a useful observation for preventing leaching and evaporation loss of herbicide. In the soil column, the release of linuron occurred in a slow and sustained manner for 240 h. A soil adsorption study showed a decrease in ground water ubiquity score (GUS) for linuron-encapsulated hydrogel as compared to commercial formulations. It can reduce groundwater contamination risk due to the leaching of the linuron herbicide. Degradation of CRF may improve micronutrient and soil quality.

The unsustainable use of manmade chemicals poses significant threats to biodiversity and human health. Emerging evidence highlights the potential of certain chemicals to cause transgenerational impacts on metabolic health. Here, we investigate male transmitted epigenetic transgenerational effects of the anti-androgenic herbicide linuron in the pancreas of Xenopus tropicalis frogs, and their association with metabolic phenotypes. Reduced representation bisulfite sequencing (RRBS) was used to assess genome-wide DNA methylation patterns in the pancreas of adult male F2 generation ancestrally exposed to environmentally relevant linuron levels (44 ± 4.7 μg/L). We identified 1117 differentially methylated regions (DMRs) distributed across the X. tropicalis genome, revealing potential regulatory mechanisms underlying metabolic disturbances. DMRs were identified in genes crucial for pancreatic function, including calcium signalling (clstn2, cacna1d and cadps2), genes associated with type 2 diabetes (tcf7l2 and adcy5) and a biomarker for pancreatic ductal adenocarcinoma (plec). Correlation analysis revealed associations between DNA methylation levels in these genes and metabolic phenotypes, indicating epigenetic regulation of glucose metabolism. Moreover, differential methylation in genes related to histone modifications suggests alterations in the epigenetic machinery. These findings underscore the long-term consequences of environmental contamination on pancreatic function and raise concerns about the health risks associated with transgenerational effects of pesticides. [Display omitted] • Linuron exposure caused transgenerational epigenetic changes in frog pancreas. • 1117 Differentially Methylated Regions (DMRs) in F2 male X. tropicalis. • DMRs in genes related to F2 phenotypical metabolic changes. • Levels of methylation in relevant genes were correlated with plasma glucose levels. • Methylation of T2D markers tcf7l2 and adcy5 correlated to glucose metabolism changes. [ABSTRACT FROM AUTHOR]

TiO2 pillared clay was prepared by intercalation of titan polyoxocation into interlamelar space of an Algerian montmorillonite and used for the photocatalytic degradation of the linuron herbicide as a target pollutant in aqueous solution. The TiO2 pillared montmorillonite (Mont-TiO2) was characterized by X-ray photoelectron spectroscopy (XPS), X-Ray diffraction (XRD), X-Ray fluorescence (XRF), scanning electronic microscopy (SEM), thermogravimetry and differential thermal analysis (TG-DTA), Fourier transformed infra-red (FT-IR), specific area and porosity determinations. This physicochemical characterization pointed to successful TiO2 pillaring of the clay. The prepared material has porous structure and exhibit a good thermal stability as indicated by its surface area after calcination by microwave. The effects of operating parameters such as catalyst loading, initial pH of the solution and the pollutant concentration on the photocatalytic efficiency and COD removal were evaluated. Under initial pH of the solution around seven, pollutant concentration of 10 mg/L and 2.5 g/L of catalyst at room temperature, the degradation efficiency and COD removal of linuron was best then the other operating conditions. It was observed that operational parameters play a major role in the photocatalytic degradation process. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

A two-year field experiment was conducted at experimental farm, Faculty of Agriculture, Kafrelsheikh University, Egypt during both 2015/2016 and 2016/2017 successive winter growing seasons to the effect of some pre and postemergence herbicides on physiological and histological characters, productivity and quality of carrots (cv. "Tokita"). Each experiment included nine weed control treatments which consists of four herbicides (three herbicides used as pre-emergence i. e. prometryn 312.5 or 625g; linuron 112.5 or 225g and pendimethalin 425 or 850 g a. i./fed. while the other herbicide i. e. fluazifop-p-butyl 62.5 g was used as post-emergence, and hand hoeing twice (at 30 and 45 DAS) and weedy chick. Significant differences on chlorophyll content (chi. a, b and total) were induced during the both seasons. Prometryn gave the highest value of chlorophyll a. Pendimethalin gave the highest value of RWC and least of LWD. The highest values of carrot root half diameters and cortex tissue thickness were detected by pendimethalin treatment. All tested herbicides gave the highest values of quality characters in carrot roots, followed by hand weeding of the annual weeds. [ABSTRACT FROM AUTHOR]

Biochar is increasingly been used as a soil amendment to improve water-holding capacity, reduce nutrient leaching, increase soil pH, and also as a means to reduce contamination through sorption of heavy metals or organic pollutants. The sorption behavior of three phenylurea herbicides (monuron, diuron and linuron) on five biochars (Enhanced Biochar, Hog Waste, Turkey Litter, Walnut Shell and Wood Feedstock) and an agricultural soil (Yolo silt loam) was investigated using a batch equilibration method. Sorption isotherms of herbicides to biochars were well described by the Freundlich model (R(2) = 0.93-0.97). The adsorption KF values ranged from 6.94 to 1306.95 mg kg(-1) and indicated the sorption of herbicides in the biochars and Yolo soil was in the sequence of linuron > diuron > monuron and walnut shell biochar > wood feedstock biochar > turkey litter biochar > enhanced biochar > hog waste biochar > Yolo soil. These data show that sorption of herbicides to biochar can have both positive (reduced off-site transport) and negative (reduced herbicide efficacy) implications and specific biochar properties, such as H/C ratio and surface area, should be considered together with soil type, agriculture chemical and climate condition in biochar application to agricultural soil to optimize the system for both agricultural and environmental benefits.

TiO2 pillared clay was prepared by intercalation of titan polyoxocation into interlamelar space of an Algerian montmorillonite and used for the photocatalytic degradation of the linuron herbicide as a target pollutant in aqueous solution. The TiO2 pillared montmorillonite (Mont-TiO2) was characterized by X-ray photoelectron spectroscopy (XPS), X-Ray diffraction (XRD), X-Ray fluorescence (XRF), scanning electronic microscopy (SEM), thermogravimetry and differential thermal analysis (TG-DTA), Fourier transformed infra-red (FT-IR), specific area and porosity determinations. This physicochemical characterization pointed to successful TiO2 pillaring of the clay. The prepared material has porous structure and exhibit a good thermal stability as indicated by its surface area after calcination by microwave. The effects of operating parameters such as catalyst loading, initial pH of the solution and the pollutant concentration on the photocatalytic efficiency and COD removal were evaluated. Under initial pH of the solution around seven, pollutant concentration of 10 mg/L and 2.5 g/L of catalyst at room temperature, the degradation efficiency and COD removal of linuron was best then the other operating conditions. It was observed that operational parameters play a major role in the photocatalytic degradation process. [ABSTRACT FROM AUTHOR]

We investigated changes in 8-hydroxy-2-deoxyguanosine (8-OHdG) activity which is a product of oxidative DNA damage, histopathological changes and antioxidant responses in liver and gill tissues of rainbow trout, following a 21-day exposure to three different concentrations of linuron (30 µg/L, 120 µg/L and 240 µg/L). Our results indicated that linuron concentrations caused an increase in LPO levels of liver and gill tissues (p < 0.05). While linuron induced both increases and decreases in GSH levels and SOD activity, CAT activity was decreased by all concentrations of linuron (p < 0.05). The immunopositivity of 8-OHdG was detected in the hepatocytes of liver and in the epithelial and chloride cells of the secondary lamellae of the gill tissues. Our results suggested that linuron could cause oxidative DNA damage by causing an increase in 8-OHdG activity in tissues, and it induces histopathological damage and alterations in the antioxidant parameters of the tissues. [ABSTRACT FROM AUTHOR]

Phenyl urea herbicides are being extensively used for weed control in both agricultural and non-agricultural applications. Linuron is one of the key herbicides in this family and is in wide use. Like other phenyl urea herbicides, it is known to have toxic effects as a result of its persistence in the environment. The natural removal of linuron from the environment is mainly carried through microbial biodegradation. Some microorganisms have been reported to mineralize linuron completely and utilize it as a carbon and nitrogen source. Variovorax sp. strain SRS 16 is one of the known efficient degraders with a recently sequenced genome. The genomic data provide an opportunity to use a genome-scale model for improving biodegradation. The aim of our study is the construction of a genome-scale metabolic model following automatic and manual protocols and its application for improving its metabolic potential through iterative simulations. Applying flux balance analysis (FBA), growth and degradation performances of SRS 16 in different media considering the influence of selected supplements (potential carbon and nitrogen sources) were simulated. Outcomes are predictions for the suitable media modification, allowing faster degradation of linuron by SRS 16. Seven metabolites were selected for in vitro validation of the predictions through laboratory experiments confirming the degradation-promoting effect of specific amino acids (glutamine and asparagine) on linuron degradation and SRS 16 growth. Overall, simulations are shown to be efficient in predicting the degradation potential of SRS 16 in the presence of specific supplements. The generated information contributes to the understanding of the biochemistry of linuron degradation and can be further utilized for the development of new cleanup solutions without any genetic manipulation.

The frequent exposure of agricultural soils to pesticides can lead to microbial adaptation, including the development of dedicated microbial populations that utilize the pesticide compound as a carbon and energy source. Soil from an agricultural field in Halen (Belgium) with a history of linuron exposure has been studied for its linuron-degrading bacterial populations at two time points over the past decade and Variovorax was appointed as a key linuron degrader. Like most studies on pesticide degradation, these studies relied on isolates that were retrieved through bias-prone enrichment procedures and therefore might not represent the in situ active pesticide-degrading populations. In this study, we revisited the Halen field and applied, in addition to enrichment-based isolation, DNA stable isotope probing (DNA-SIP), to identify in situ linuron-degrading bacteria in linuron-exposed soil microcosms. Linuron dissipation was unambiguously linked to Variovorax and its linuron catabolic genes and might involve the synergistic cooperation between two species. Additionally, two novel linuron-mineralizing Variovorax isolates were obtained with high 16S rRNA gene sequence similarity to strains isolated from the same field a decade earlier. The results confirm Variovorax as a prime in situ degrader of linuron in the studied agricultural field soil and corroborate the genus as key for maintaining the genetic memory of linuron degradation functionality in that field. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Plant Production is the property of Egyptian National Agricultural Library (ENAL) 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.)

In this study, commercial activated carbon, NORIT SA2 was used for removal of linuron and isoproturon pesticides from aqueous solutions. The main parameters of adsorption process such as dosage of adsorbent, contact time and initial concentration of linuron and isoproturon were investigated. Also, pH value for adsorption on activated carbon, NORIT SA2 was studied. Adsorption equilibrium studies were carried out in batch systems. Results were modeled by adsorption isotherms: Langmuir, Freundlich and Temkin isotherms, which gave correlation coefficients r = 0.878, 0.974 and 0.953 for linuron and r = 0.804, 0.977 and 0.936 for isoproturon, respectively. The maximum adsorption capacities calculated from the Langmuir isotherms were 312.50 mg g-1 for linuron and 182.00 mg g-1 for isoproturon at room temperature. Commonly applied kinetic models such as the pseudo-first order model, the pseudo-second order model and the intraparticle diffusion model, were studied for adsorption kinetics of linuron and isoproturon. The data were best fitted to the pseudo-second order kinetic model. It could be concluded that activated carbon, NORIT SA2 is effective adsorbent for the removal of linuron and isoproturon from aqueous solutions. [ABSTRACT FROM AUTHOR]

The herbicide linuron can cause endocrine disrupting effects in Xenopus tropicalis frogs, including offspring that were never exposed to the contaminant. The mechanisms by which these effects are transmitted across generations need to be further investigated. Here, we examined transgenerational alterations of brain and testis DNA methylation profiles paternally inherited from grandfathers developmentally exposed to an environmentally relevant concentration of linuron. Reduced representation bisulfite sequencing (RRBS) revealed numerous differentially methylated regions (DMRs) in brain (3060 DMRs) and testis (2551 DMRs) of the adult male F2 generation. Key genes in the brain involved in somatotropic (igfbp4) and thyrotropic signaling (dio1 and tg) were differentially methylated and correlated with phenotypical alterations in body size, weight, hind limb length and plasma glucose levels, indicating that these methylation changes could be potential mediators of the transgenerational effects of linuron. Testis DMRs were found in genes essential for spermatogenesis, meiosis and germ cell development (piwil1, spo11 and tdrd9) and their methylation levels were correlated with the number of germ cells nests per seminiferous tubule, an endpoint of disrupted spermatogenesis. DMRs were also identified in several genes central for the machinery that regulates the epigenetic landscape including DNA methylation (dnmt3a and mbd2) and histone acetylation (hdac8, ep300, elp3, kat5 and kat14), which may at least partly drive the linuron-induced transgenerational effects. The results from this genome-wide DNA methylation profiling contribute to better understanding of potential transgenerational epigenetic inheritance mechanisms in amphibians., 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. All work was carried out when employed at Uppsala University. Sofie Svanholm is now employed at The Swedish Chemicals Agency but The Swedish Chemicals Agency was not involved in any part of this study. The views expressed in this study are that of the author alone and do not reflect those of the Swedish Chemicals Agency., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

This research is to study the efficacy of linuron herbicide removal from wastewater with four adsorbents. These adsorbents were 1) synthetic zeolite NaY combined with activated carbon (SZA) 2) synthetic zeolite NaY with activated carbon and modified with HDTMA surfactant (MSZA) 3) synthetic zeolite NaY (SZ) and 4) synthetic zeolite NaY and modified with HDTMA surfactant (MSZ). The results showed that the adsorption of linuron herbicide of all adsorbents increased rapidly and approach to equilibrium at 24 h. When the amount of adsorbent increased, the adsorption of linuron herbicide also increased. The maximum adsorption efficiency SZA, MSZA, SZ and MSZ were 63.49 %, 77.97 %, 66.57 % and 38.52 %, respectively at a concentration of 2 ppm linuron, 0.1 g. of adsorbents and 24 h. The adsorption isotherm corresponded to Langmuir model. XRD, FT-IR and SEM techniques were use to study the characteristics of these adsorbents. In summary, zeolite synthesis combined with activated carbon (ZSA) has efficiency in adsorbing linuron herbicide and as an alternative to eliminate pesticide, herbicide, organic toxins and other wastes released into the environment. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing 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.)

Although the herbicide linuron is banned for use in the EU due to its reproductive and developmental toxicity, it can still be found in randomly sampled foods grown in and outside the EU. It is not clear if metabolites of linuron can contribute to the endocrine disrupting effects following exposure to the parent compound. To address this gap, we analysed linuron and the metabolites 1-(3,4-dichlorophenyl) urea (DCU), 3,4-dichloroaniline (DCA) and 1-(3,4-dichlorophenyl)-3-methoxyurea (DCXU) for androgen receptor (AR) activities and effects on steroidogenesis. Generally, linuron and the metabolites showed qualitatively similar antiandrogenic profiles, but potencies varied. All compounds were AR antagonists, with linuron showing highest potency (IC 50 of 2.8 μM). The overall picture of effects on steroidogenesis showed that linuron and metabolites increased the levels of estrogens and corticosteroids, whereas the synthesis of androgens was inhibited. The metabolite DCU was by far the most potent inhibitor of testosterone synthesis (IC 50 of 6.7 μM compared to IC 50 of 51.1 μM for linuron). We suggest that it is likely that the metabolites contribute to the antiandrogenic effects of linuron in vivo , especially by inhibiting testosterone synthesis. [Display omitted] • Potency ranking for hAR antagonism: Linuron > DCXU > DCA > DCU. • Metabolite DCU is the most potent testosterone synthesis inhibitor in vitro. • The metabolites may contribute to linuron-induced male reproductive toxicity. [ABSTRACT FROM AUTHOR]

The sorption of three herbicides (alachlor, atrazine and linuron) on samples from six peats of progressive degree of maturity (fibric, hemic or sapric types) and soil samples (dryland agricultural Calcic Luvisol amended with the peats) was determined. The extent of the sorption was examined in terms of peat maturity (up to 220 analytical descriptors of the peat material). In most cases, a sorption enhancement effect was observed in the peat–soil system compared with the sum of the sorption in peat and soil alone, i.e., a positive interaction leading to an increase in soil matrix reactive sites. The analytical characteristics of humic and bitumen peat subfractions were useful in forecasting sorption performance. This was the case for high molecular weight hydrophobic fractions, the extent of the alkyl domain in humic substances and oxygen-containing groups. Correspondence analysis illustrated how different characteristics of the peats played a distinct role in sorption in the herbicide–peat system or in the soil–peat–herbicide system. In the former system, there was a relevant bearing of parameters indicating low peat maturity, whereas in the second the sorption was mainly explained by peat colloidal properties, including the concentration and base saturation of oxygen-containing functional groups.

Potato (Solanum tuberosum L.) is grown in over 160 countries. Weed competition and environmental stressors during the vegetative growth stage significantly impact crop yields. An experiment was conducted from 2012 to 2014 in Poland to assess the effect of herbicides linuron + clomazone (L+CH) and metribuzin (M) as well as herbicides mixed with biostimulants (linuron + clomazone and algae extract of Ecklonia maxima—auxins and gibberellins (L+CH+E) and metribuzin + sodium p-nitrophenolate, sodium o-nitrophenolate and sodium 5-nitroguaiacolate (M+S)) on weed infestation, marketable yield and yield components of the following three table potato cultivars: Bartek, Gawin and Honorata. In plots where potato had been treated with herbicides and herbicides mixed with biostimulants, a decline in the fresh matter of weeds was observed, ranging from 72.4% to 96.1%, which was followed by an increase in potato marketable yield (from 27.5% to 61%) and improved parameters of S. tuberosum yield components, compared with the control. Linear correlation coefficients indicated that the following characteristics: marketable yield, weight of tubers per plant and average weight per tuber were associated with weed infestation determined prior to potato harvest.

Linuron is a selective herbicide used for the control of broadleaf weeds. Its mode of action is the inhibition of photosynthesis. The QuEChERS method for extraction of linuron residues from chamomile was used. The LC–MS/MS method was used for determination of linuron residues. Its linearity was studied in a range of 0.025-0.50 μg/ml using matrix-matched calibration, and the determination coefficient (R2) was higher than 0.99. Blank chamomile samples were spiked with linuron solution at three concentration levels yielding recoveries of over 90%. The internal standard added in all samples was isoproturon–d6. There were no linuron residues in chamomile flowers, while the residues ranged from 0.010 to 0.040 mg/kg in the flower stalk samples.

Two fungal strains were applied to soil polluted with herbicide in order to determine their degradation potential. Three experimental setups were used. In the first setup, the soil in pots was contaminated by linuron in final concentration of 1 ppm. Suspensions of Phanerocheate chrysosporium and Trichoderma asperellum were applied sepa­rately or in combination. Tomato plantlets were transplanted and chlorophyll content in their leaves was determined at two time points during plant growth. In the second setup in pots, the final concentration of linuron was lower, 0.45 ppm. In the third setup 0.1 ppm of linuron was applied in the field plot. Plantlets of lettuce were transplanted and chlorophyll content was measured as indicator of plant stress. The content of linuron in soil was determined by HPLC. The applied fungal strains significantly reduced toxic effect of 0.45 ppm linuron on plants, which was not the case for 1 ppm linuron. Both fungi, applied separately or in combination, were effective in decreasing the linuron content in the soil. However, in field conditions the combination of both fungi was the most effective. [Projekat Ministarstva nauke Republike Srbije, br. III43010]

The phenylurea herbicide, linuron (LIN), is used to control various types of weeds. Despite its efficient role in controlling weeds, it presents a persistent problem to the environment. In the current study, phytoremediation properties of transgenic CYP1A2 Arabidopsis thaliana plants to LIN were assessed. CYP1A2 gene was firstly cloned and expressed in bacteria before proceeding to plants. In presence of LIN, The growth of CYP1A2 expressing bacteria was superior compared to control bacteria transformed with the empty bacterial expression vector pET22b(+). No clear morphological changes were detected on CYP1A2 transgenic plants. However, significant resistance to LIN herbicide application either via spraying the foliar parts of the plant or via supplementation of the herbicide in the growth medium was observed for CYP1A2 transformants. Plant growth assays under LIN stress provide strong evidence for the enhanced capacity of transgenic lines to grow and to tolerate high concentrations of LIN compared to control plants. HPLC analyses showed that detoxification of LIN by bacterial extracts and/or transgenic plant leaves is improved as compared to the corresponding controls. Our data indicate that over expression of the human CYP1A2 gene increases the phytoremediation capacity and tolerance of Arabidopsis thaliana plants to the phenylurea herbicide linuron. [ABSTRACT FROM AUTHOR]

The present study aimed to optimize ozone (O 3 ) treatments, as gas and dissolved in water, to remove difenoconazole and linuron in carrots. We employed a central composite design to study three variables governing the efficacy of treatments: O 3 concentration, temperature and treatment time. The temperature did not influence the efficacy of treatments. The removal percentage of pesticides increases with increases in ozone concentration and the time of treatment. O 3 application promoted the removal of more than 80% of pesticides when the roots were exposed for approximately 120 min at 5 and 10 mg L −1 , respectively, in treatments with O 3 as gas and dissolved in water. After storage, pesticide removal was higher than 98% for difenoconazole and 95% for linuron. The degradation products from the pesticides resulting from treatment were monitored, but none were found. This is the first report demonstrating the removal of difenoconazole and linuron from carrots by ozone. [ABSTRACT FROM AUTHOR]

Several short-term whole-organism bioassays based on transgenic aquatic models are now under validation by the OECD (Organization for Economic Co-operation and Development) to become standardized test guidelines for the evaluation of the endocrine activity of substances. Evaluation of the endocrine disrupting capacity of pesticides will be a domain of applicability of these future reference tests. The herbicide linuron and the insecticide fenoxycarb are two chemicals commonly used in agricultural practices. While numerous studies indicate that linuron is likely to be an endocrine disruptor, there is little information available on the effect of fenoxycarb on vertebrate endocrine systems. Using whole-organism bioassays based on transgenic Xenopus laevis tadpoles and medaka fry we assessed the potential of fenoxycarb and linuron to disrupt thyroid, androgen and estrogen signaling. In addition we used in silico approach to simulate the affinity of these two pesticides to human hormone receptors. Linuron elicited thyroid hormone-like activity in tadpoles at all concentrations tested and, showed an anti-estrogenic activity in medaka at concentrations 2.5 mg/L and higher. Our experiments suggest that, in addition to its previously established anti-androgenic action, linuron exhibits thyroid hormone-like responses, as well as acting at the estrogen receptor level to inhibit estrogen signaling. Fenoxycarb on the other hand, did not cause any changes in thyroid, androgen or estrogen signaling at the concentrations tested. [ABSTRACT FROM AUTHOR]

Linuron is a widely used herbicide; its toxicity on the male reproductive system has been recognized. The current study was designed to explore the molecular mechanism underlying linuron-induced reproductive toxicity. Pregnant rats received daily oral gavage of linuron at the dose of 120 mg/kg/d from gestation day (GD)12 to GD17. Tissues from male offspring rats were collected for pathological examination and microarray gene expression profiling. Changes in gene expression were further verified by quantitative real-time RT-PCR. Data showed that linuron-exposed offspring rats had a decreased sperm count (88% of controls) and disrupted acrosome formation. There were evident damages in seminiferous tubules and abnormal morphology in mesenchymal cells in samples from linuron-exposed animals. Microarray analysis indicated that the expressions of testosterone synthesis-associated genes, i.e., Star, P450scc, 3β-Hsd, Abp, Cox7a2, Pcna, p450c17 and 17β-Hsd were significantly altered by linuron exposure, along with other genes involving in cell proliferation and apoptosis, such as c-myc, S6K, Apaf1 , and TSC1 . These data indicate that linuron upon entering male offspring body can directly or indirectly interact with the androgen production and function; linuron-induced alteration in genes encoding testosterone synthesis is likely a major factor in linuron-induced male reproductive toxicity. [ABSTRACT FROM AUTHOR]

Lignocellulosic wastes and by-products containing lignin are now available in large amounts from forestry and industrial activities, and could be promising organic materials for the biosorption of pesticides by soils in order to reduce point-source pollution. Adding these materials to soil requires understanding the process of pesticide sorption-desorption by wood-soils, as sorption capacity could increase, with changes in pesticide bioavailability and final fate. The objective of this work was to study the effect that pine and oak wood added to soils had on the sorption/desorption of the pesticides linuron, alachlor, and metalaxyl. Experiments were conducted with two sandy loam and sandy clay soils each amended with two wood doses (5% and 50%) after different incubation times (0, 5 and 12 months). A low wood dose (5%) had no significant impact on the sorption (K f ) of alachlor, but K f increased for linuron (up to 5.4–1.7 times) and metalaxyl (up to 4.4 and 8.6 times) in all wood-soil systems. The results were not significantly different after different incubation times. The desorption results indicated that wood decreases the sorption irreversibility of alachlor, and increases that of linuron and metalaxyl, with a varying effect of the wood-soil incubation time. The addition of a high wood dose to soil (50%) was more significant for increasing the sorption of all the pesticides, and the sorbed amounts remaining after desorption (>49% for linuron, >33% for alachlor and >6% for metalaxyl), although there was no apparent discrimination between the two types of woods. The role of the nature of the organic carbón (K oc values) for sorption was evidenced for alachlor and metalaxyl, but not for linuron. These outcomes are of interest for extending wood application to soil as a barrier for avoiding environmental risk by point-source pollution due to the use and management of pesticides in farming systems. [ABSTRACT FROM AUTHOR]

Linuron is a widely used herbicide in agriculture; its endocrine disruptive toxicity has recently received public attention. This study was designed to examine the developmental toxicity of linuron on the reproductive system of male offspring following maternal exposure. Mother rats received oral gavages of linuron, once daily, at the dose of 0, 50, 100, 150 or 200 mg/kg, from gestational day (GD)13 to GD18; gonadal organs from GD20 fetuses were examined. Data indicated that exposed male offspring had a significantly shortened anogenital distance. Pathological examination further revealed a lack of fusion in the urogenital fold in treated fetuses, the damaged seminiferous tubules, and the injured Leydig cell ultrastructure. Analysis of serum testosterone concentrations at postnatal day (PND)2 showed a significant dose-related reduction (about 33.7–58.75%, r = −0.838, p < 0.05) as compared to controls. Immunohistochemical results demonstrated a significantly reduced expression of enzymes pertinent to the testosterone production including P450scc, 3β-HSD, and PCNA in Leydig cells (p < 0.05). qPCR studies confirmed decreased levels of mRNAs encoding P450scc, 3β-HSD and PCNA (p < 0.05). Taken together, these data suggest that maternal exposure to linuron hampers the male gonadal organ development; this appears to be due to linuron’s direct action on the production of testosterone in fetal and postnatal offspring. [ABSTRACT FROM AUTHOR]

Linuron is a widely used herbicide to control grasses and annual broad leaf weeds. It is known that linuron has toxic effects on different organisms. However, the toxic effects of linuron on aquatic organisms, especially fish, is completely unknown. Thus, we aimed to investigate changes in 8-hydroxy-2-deoxyguanosine (8-OHdG) and nuclear factor kappa B (NFkB) activity, histopathological changes, antioxidant responses and acetylcholinesterase (AChE) activity in rainbow trout brain after exposure to linuron. Fish were exposed to 30 μg/L, 120 μg/L and 240 μg/L concentrations of linuron for twenty-one days. Brain tissues were taken from fish for 8-OHdG and NFkB activity, histopathological examination and determination of superoxide dismutase (SOD), catalase (CAT) enzyme activity, lipid peroxidation (LPO), and reduced glutathione (GSH) levels. Our data indicated that high linuron concentrations caused a decrease in GSH levels, SOD and CAT activities in brain tissues ( p < 0.05). LPO levels were significantly increased by 240 μg/L linuron. All concentrations caused a significant inhibition in brain AChE enzyme activity ( p < 0.05). Immunopositivity was detected for 8-OHdG and NFkB, and linuron exposure caused histopathological damage to the brain tissues. The results of this study can provide useful information for understanding of linuron-induced toxicity. [ABSTRACT FROM AUTHOR]

Background: Maternal occupational exposure to pesticides has been linked to adverse birth outcomes but associations with residential pesticide exposures are inconclusive., Objectives: To explore associations between residential exposure to specific pesticides and birth outcomes using individual level exposure and pregnancy/birth data., Methods: From all 2009-2013 singleton births in the Dutch birth registry, we selected mothers > 16 years old living in non-urban areas, who had complete address history and changed addresses at most once during pregnancy (N = 339,947). We estimated amount (kg) of 139 active ingredients (AI) used within buffers of 50, 100, 250 and 500 m around each mother's home during pregnancy. We used generalized linear models to investigate associations between 12 AIs with evidence of reproductive toxicity and gestational age (GA), birth weight (BW), perinatal mortality, child́s sex, prematurity, low birth weight (LBW), small for gestational age (SGA) and large for gestational age (LGA), adjusting for individual and area-level confounders. For the remainder 127 AIs, we used minimax concave penalty with a stability selection step to identify those that could be related to birth outcomes., Results: Regression analyses showed that maternal residential exposure to fluroxypyr-meptyl was associated with longer GA, glufosinate-ammonium with higher risk of LBW, linuron with higher BW and higher odds of LGA, thiacloprid with lower odds of perinatal mortality and vinclozolin with longer GA. Variable selection analysis revealed that picoxystrobin was associated with higher odds of LGA. We found no evidence of associations with other AIs. Sensitivity and additional analysis supported these results except for thiacloprid., Discussion: In this exploratory study, pregnant women residing near crops where fluroxypyr-meptyl, glufosinate-ammonium, linuron, vinclozolin and picoxystrobin were applied had higher risk for certain potentially adverse birth outcomes. Our findings provide leads for confirmatory investigations on these compounds and/or compounds with similar modes of action., 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 © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Two modified electrodes (Pb/PbO2 and C/PbO2) were prepared by electrodeposition and used as anodes for electrochemical degradation of linuron (phenylurea pesticide) in aqueous solution. Different operating conditions and factors affecting the treatment process including current density, temperature, initial concentration of linuron, pH, conductive electrolyte and time of electrolysis were studied and optimized. The best degradation occurred in the presence of NaCl (1 gL−1) as conductive electrolyte. After 30 min, nearly complete degradation of linuron was achieved (92% and 84%) using C/PbO2 and Pb/PO2 electrodes at pH 7 and 1.5, respectively. Higher degradation efficiency was obtained at low temperature (5–10 °C). The optimum current density for the degradation of linuron on both electrodes was (150 mAcm−2).

Abstract The conclusions of EFSA following the peer review of the initial risk assessments carried out by the competent authorities of the rapporteur Member State Italy and co‐rapporteur Member State Germany for the pesticide active substance linuron are reported. The context of the peer review was that required by Commission Implementing Regulation (EU) No 844/2012. The conclusions were reached on the basis of the evaluation of the representative use of linuron as a herbicide on carrots. The reliable end points, appropriate for use in regulatory risk assessment, are presented. Missing information identified as being required by the regulatory framework is listed. Concerns are identified.

This paper summarises the results of voltammetric studies on the herbicide 3-(3,4-dichlorophenyl)-1-methoxy-1-methylurea (Linuron), using a carbon paste electrode containing tricresyl phosphate (TCP-CPE) as liquid binder. The principal experimental conditions, such as the pH effect, investigated in Britton-Robinson buffer solutions (pH 2.0–7.0), the peak characteristics for the analyte of interest, or instrumental parameters for the differential pulse voltammetric mode were optimized for the method. As found out, the best electroanalytical performance of the TCP-CPE was achieved at pH 2.0, whereby the oxidation peak of Linuron appeared at ca. +1.3 V vs. SCE. The analytical procedure developed offers good linearity in the concentration range of 1.25–44.20 μg mL−1 (1.77 × 10−4–5.05 × 10−6 mol L−1), showing - for the first time - the applicability of the TCP-CPE for anodic oxidations in direct voltammetry (without accumulation). The method was then verified by determining Linuron in a spiked river water sample and a commercial formulation and the results obtained agreed well with those obtained by the reference HPLC/UV determination.

About a half of the herbicides used at present in agnculture inhibit the light reactions in photosynthesis. Triazines and phenylureas shut down the photosynthetic process in susceptible plants by binding to specific sites within the plants photosystem II (PS II) complex. Both of them bind at the QB site on the Dl protein of PS II, and prevent the transport of electrons between the primary electron acceptor Q and the plastoquinone (PQ). Herbicides can be highly toxic to human and animal health (triazines are possible human carcinogens). Their indiscriminate use has serious environmental implications, for example pollution of soil and water. We compare two heibicides to investigate the one of lowest environmental toxicity but of high toxicity to weeds.

In this study, physical, chemical, and electrochemical properties of lab-made boron-doped diamond electrodes (BDDE) prepared by hot filaments chemical vapor deposition under different conditions have been investigated. The B/C ratio in the gas phase varied in the range of 0-20,000 ppm and the content of CH in H was changed in the interval of 0.5-2 %. Scanning electron microscopy and Raman spectroscopy were used for characterization of BDD films. Cyclic voltammetry and electrochemical impedance spectroscopy of the redox system [Fe(CN)] were used for electrochemical characterization of prepared electrodes. Finally, all BDDEs in combination with differential pulse voltammetry were tested for herbicide linuron determination under optimized experimental conditions. Graphical abstract: [ABSTRACT FROM AUTHOR]

The conclusions of EFSA following the peer review of the initial risk assessments carried out by the competent authorities of the rapporteur Member State Italy and co-rapporteur Member State Germany for the pesticide active substance linuron are reported. The context of the peer review was that required by Commission Implementing Regulation ( EU) No 844/2012. The conclusions were reached on the basis of the evaluation of the representative use of linuron as a herbicide on carrots. The reliable end points, appropriate for use in regulatory risk assessment, are presented. Missing information identified as being required by the regulatory framework is listed. Concerns are identified. [ABSTRACT FROM AUTHOR]

The photocatalytic degradation of 3-[3,4-(dichlorophenyl)-1-methoxy-1-methylurea] (Linuron), which is one of phenylurea herbicides, has been studied using natural iron oxide (NIO) as a heterogeneous catalyst in the presence of H 2 O 2 under various conditions. The characterization of this catalyst revealed that NIO has a mixed elemental composition and consists mainly of iron oxide (α-Fe 2 O 3 ). This powder contains hematite as iron source and its dissolution provides Fe 3+ cations for the Fenton-like reaction in solution. The degradation rate was strongly influenced by pH, initial concentrations of H 2 O 2 , amount of NIO particles and type of irradiation (artificial or natural sunlight). An initial Linuron concentration of 4.0 × 10 −5 mol L −1 was completely degraded after 45 min under the optimum conditions. The decrease of chemical oxygen demand (COD) as a result of mineralization of the herbicide was observed i.e., 99.99% of the initial concentration of Linuron and over 80% of COD were removed after 6 h under our experimental conditions. The degradation of Linuron is mainly due to the formation of hydroxyl radicals as confirmation by the use of 2.0% of isopropanol as an HO scavenger. The decomposition of Linuron gave eight main intermediate products, and a degradation mechanism is suggested on the basis of these identified intermediates. The use of NIO is interesting; because in addition to its catalytic effect, its high density enables an easy solid-liquid separation, making it a versatile material for environmental applications. [ABSTRACT FROM AUTHOR]

On-farm biopurification systems (BPSs) treat pesticide-contaminated wastewater at farms through biodegradation and sorption processes. However, information on the microbiota involved in pesticide removal in BPSs is scarce. Here we report on the response of BPS bacterial communities to the herbicide linuron (BPS+) compared with the control (BPS-) in a microcosm experiment. Both denaturing gradient gel electrophoresis (DGGE) and pyrosequencing of 16S rRNA gene fragments amplified from community DNA indicated shifts in the bacterial community after linuron application. Responding populations belonged to taxa that were previously reported from linuron degrading consortia cultivated from soil (Hyphomicrobiaceae, Comamonadaceae, Micrococcaceae). In addition, numerous taxa with increased relative abundance were identified that were previously not associated with linuron degradation. The relative abundance of IncP-1 korB copies increased in response to linuron application. Amplicon pyrosequencing of IncP-1 trfA genes revealed a high IncP-1 plasmid diversity and suggested that populations carrying IncP-1β plasmids increased in relative abundance. Transferable mercury resistance plasmids were exogenously captured from BPS+/BPS-, and in three transconjugants from BPS+ the gene hylA was detected. Our data suggest the existence of a multispecies linuron degrading bacterial food web and an involvement of IncP-1 plasmids in the adaptation of bacterial communities to pesticide pollution in BPSs. [ABSTRACT FROM AUTHOR]