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Organophosphorous (OP) pesticides can cause many human diseases. In this study, the separation and determination of two organophosphorous pesticides (diazinon and methyl-parathion) in biological samples using solid-phase extraction method prior to their measurements by high‐performance liquid chromatography (HPLC) were investigated. Herein, a new functionalized cerium-based metal–organic framework (MOF) bearing oxime moiety, denoted here UiO-66(Ce)-MO, was synthesized through two-synthetic steps from the pristine UiO-66(Ce) and then applied as an efficient porous adsorbent for the extraction of pesticides from biological samples. Various techniques including Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and Brunauer–Emmett–Teller (BET) analysis were used for the description of adsorbent. The optimization of variables was performed by Box–Behnken design combined with response surface methodology. The factors' effects including pH, eluent volume (EV), sample flow rate (SF) and eluent flow rate (EF) were also examined. The optimum conditions for both compounds were pH 5.5, eluent volume 0.6 mL, SF 2 mL min−1, and EF 0.2 mL min−1, leading to 97.1% and 96.0% removal of diazinon and methyl-parathion, respectively. Under the optimum conditions, the maximum adsorption capacity was obtained 454.5 mg g−1 for methyl-parathion and 476.2 mg g−1 for diazinon. The limit of detection (LOD) was found to be 0.04 μgL−1 for diazinon and 0.06 μgL−1 for methyl-parathion. Sensitivity analysis showed that pH plays a significant role on the efficiency of both organic pollutants. Remarkably, the results showed that this adsorbent outperforms the other UiO-66(Ce) samples and is suitable for separation and determination of these organic materials from water and biological real samples (blood plasma and urine). A porous oxime-functionalized Ce-MOF, UiO-66(Ce)-MO, was synthesized and applied for efficient extraction and determination of trace amounts of methyl-parathion and diazinon from water and biological samples. [ABSTRACT FROM AUTHOR]

Pesticide pollution in recent times has emerged as a grave environmental problem contaminating both aquatic and terrestrial ecosystems owing to their widespread use. Bioremediation using gene editing and system biology could be developed as an eco-friendly and proficient tool to remediate pesticide-contaminated sites due to its advantages and greater public acceptance over the physical and chemical methods. However, it is indispensable to understand the different aspects associated with microbial metabolism and their physiology for efficient pesticide remediation. Therefore, this review paper analyses the different gene editing tools and multi-omics methods in microbes to produce relevant evidence regarding genes, proteins and metabolites associated with pesticide remediation and the approaches to contend against pesticide-induced stress. We systematically discussed and analyzed the recent reports (2015–2022) on multi-omics methods for pesticide degradation to elucidate the mechanisms and the recent advances associated with the behaviour of microbes under diverse environmental conditions. This study envisages that CRISPR-Cas, ZFN and TALEN as gene editing tools utilizing Pseudomonas, Escherichia coli and Achromobacter sp. can be employed for remediation of chlorpyrifos, parathion-methyl, carbaryl, triphenyltin and triazophos by creating gRNA for expressing specific genes for the bioremediation. Similarly, systems biology accompanying multi-omics tactics revealed that microbial strains from Paenibacillus, Pseudomonas putida, Burkholderia cenocepacia, Rhodococcus sp. and Pencillium oxalicum are capable of degrading deltamethrin, p-nitrophenol, chlorimuron-ethyl and nicosulfuron. This review lends notable insights into the research gaps and provides potential solutions for pesticide remediation by using different microbe-assisted technologies. The inferences drawn from the current study will help researchers, ecologists, and decision-makers gain comprehensive knowledge of value and application of systems biology and gene editing in bioremediation assessments. [ABSTRACT FROM AUTHOR]

The current approach for the risk assessment of chemicals does not account for the complex human real-life exposure scenarios. Exposure to chemical mixtures in everyday life has raised scientific, regulatory, and societal concerns in recent years. Several studies aiming to identify the safety limits of chemical mixtures determined hazardous levels lower than those of separate chemicals. Following these observations, this study built on the standards set by the real-life risk simulation (RLRS) scenario and investigated the effect of long-term exposure (18 months) to a mixture of 13 chemicals (methomyl, triadimefon, dimethoate, glyphosate, carbaryl, methyl parathion, aspartame, sodium benzoate, EDTA, ethylparaben, butylparaben, bisphenol A and acacia gum) in adult rats. Animals were divided into four dosing groups [0xNOAEL (control), 0.0025xNOAEL (low dose—LD), 0.01xNOAEL (medium dose—MD) and 0.05xNOAEL (high dose-HD) (mg/kg BW/day)]. After 18 months of exposure, all animals were sacrificed, and their organs were harvested, weighed, and pathologically examined. While organ weight tended to be higher in males than in females, when sex and dose were taken into account, lungs and hearts from female rats had significantly greater weight than that of males. This discrepancy was more obvious in the LD group. Histopathology showed that long-term exposure to the chemical mixture selected for this study caused dose-dependent changes in all examined organs. The main organs that contribute to chemical biotransformation and clearance (liver, kidneys, and lungs) consistently presented histopathological changes following exposure to the chemical mixture. In conclusion, exposure to very low doses (below the NOAEL) of the tested mixture for 18 months induced histopathological lesions and cytotoxic effects in a dose and tissue-dependent manner. [ABSTRACT FROM AUTHOR]

A dual-emission fluorescent (FL) probe was constructed by coordinating Cu2+ of copper metal–organic frameworks (Cu-MOFs) with − COO− group of carbon dots (CDs) for pesticide thiophanate-methyl (TM) determination. TM was recognized by organic ligands (H2BDC and H2BDC-NH2) of Cu-MOFs via π stacking. Due to the higher affinity of Cu2+ to TM than ligands and CDs, TM chelated with Cu2+ to form TM-Cu complex. Thus coordination of Cu-MOFs was damaged and the ligands were released resulting in the FL intensity increase of Cu-MOFs (F430). And also CDs were released from CDs@Cu-MOFs hybrids and electron transfer from CDs to CuMOFs was inhibited, leading to the FL intensity increase of CDs (F600). The FL intensity ratio (F430/F600) showed a good linear relationship with TM concentrations of 0.0307–0.769 μmol L−1 with a limit of detection (LOD) of ~ 3.67 nmol L−1. The probe was successfully applied to detect TM in spiked food samples with satisfactory recoveries of 93.1–113%. Additionally, visual detection of TM was achieved according to the fluorescence color variation from blue to carmine, indicating promising application of CDs@Cu-MOFs probe. [ABSTRACT FROM AUTHOR]

Methyl parathion (MP), as a typical organophosphorus pesticide, has been widely used in pest control and plant growth regulation. Simultaneously, the problem of pesticide residues also poses a serious threat to the environment and human health. Currently, pesticide residue detection technology still faces great challenges in practical applications due to the problems of expensive facilities and complicated operations in conventional analysis methods. To address these problems, a novel nonenzymatic electrochemical pesticide sensor was reported. A zirconium-based metal organic framework material with terephthalic acid as a ligand (Zr-BDC) was designed to combine with electro-reduced graphene oxides (rGO). The Zr-BDC-rGO nanocomposite contains Zr-OH groups with high affinity for phosphate groups, endowing it with selective recognition and a higher adsorption capacity for MP. Moreover, rGO has a high specific surface area and excellent electron transport capability, making it an excellent functionalized adsorption and substrate material, which could improve the conductivity of the material and achieve a lower detection limit. Upon optimization, this sensor provided a wide linear range from 0.001 to 3.0 μg mL−1 and low limit of detection 0.5 ng mL−1 for MP. This work provides a rapid, sensitive and cost-effective sensing platform for pesticide residue detection. [ABSTRACT FROM AUTHOR]

This study aimed to find out the effective biotreatment processes of aqueous methyl parathion in stipulations of its biotransformation by potential indigenous mpd strains of Pseudomonas aeruginosa and Fusariumspp. Microbial biotransformation study of methyl parathion in contaminated synthetic wastewater at optimum conditions by P. aeruginosa mpd-5 (at temperature 33 °C, pH 7, under the aerobic condition with inoculum density of 108cells/mL) and by Fusarium spp mpd-1 (at temperature 30 °C, pH 7, under the aerobic condition with inoculum density of 25 mgL−1 dry biomass) was carried out. The major biodegradation compounds formed during the biotreatment process were analyzed by spectral studies using GCMS and FTIR. GCMS analysis of bacterial transformed compounds was p-nitrophenol, dimethylaminophenol, and glycyl-L-proline of 2-(3-methylpiperidino-4-5, 6-benzothiazin-4-one) and 2, 5-piperazinodione 3, 6-bis (2-methylpropyl). And the fungal transformed compounds were observed to be p-nitrophenol, phenol,2,4-Bis(1,1-Dimethylethyl), beta-L-arabinopyranoside-methyl, Cyclobutanethiol, 3-2(4)-thiophenone, dihydro-5-(1-methylethyl), Benzene,1,3-bis(1,1-dimethyl ethyl), Butanoic acid, 2-methyl methyl ester, and L-(+)-Ascorbic acid. The FTIR spectra of the molecule and the products of methyl parathion are observed to be changed in structures. It can be concluded from the aforementioned results and discussions that P. aeruginosa mpd-5 and Fusarium spp mpd-1 can be used in the biotreatment of pesticide wastewater having the high methyl parathion concentration and is possible by the indigenous microbial strains; they utilize as phosphate and carbon source of energy. Hence the strains can be used as a whole microbial cell, or its bioactive metabolites can be applied for the biotreatment of pesticide wastewater and potentially degrade methylparathion. [ABSTRACT FROM AUTHOR]

In the scope, the developed novel ZnSeO3/g-C3N4 nanocomposites and characterized in detail. Interestingly, the as prepared nanocomposites examined for the detoxification of organic pollutants like methyl parathion (MP) and cefuroxime drug (CF) under Visible light irradiation. The synthesized ZnSeO3/g-C3N4 nanocomposites were characterized by various techniques such as X-ray diffraction (XRD), fourier transform infra-red (FTIR), UV–Vis diffuse reflectance spectra (DRS/UV–Vis), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray spectra (EDX). The photocatalytic studies carried out by UV–Visible Spectroscopy it was exhibited that ZnSeO3/g-C3N4 nanocomposites photocatalyst was a superior photocatalytic performance with the degradation efficiency of an analytic solution of MP and CF observed about 120 mins and 80 mins. The reactive oxidative species are ·OH radical and superoxide radical O2•− involved in the photocatalytic reaction under the source of visible light irradiation by trapping experiments. After the completion of degradation process, the photocatalyst was reused by centrifugation method. The reusability of photocatalyst was highly stable up to eighth cycle. [ABSTRACT FROM AUTHOR]