Emerging Technologies for Degradation of Dichlorvos: A Review

Hesperetin-7-O-rhamnoglucoside ameliorates dichlorvos-facilitated cardiotoxicity in rats by counteracting ionoregulatory, ion pumps, redox, and lipid homeostasis disruptions

The contamination of edible agricultural goods with pesticides, including dichlorvos (DVDP), poses a substantial public health risk, promoting severe morbidity and mortality, especially in developing countries. It has been shown that hesperidin (hesperetin-7-O-rhamnoglucoside or Hes-7-RGlc) preserves cytomembrane, redox, and lipid homeostasis; unfortunately, its function on dichlorvos-incited heart damage has not been investigated. This work explored the ameliorative influence of Hes-7-RGlc on DVDP-activated cardiotoxicity. For this end, forty-two rats were randomly appropriated into seven groups (6 rats/group): Control, DVDP alone (8 mg.kg⁻¹day⁻¹), DVDP supplied with either Hes-7-RGlc (50 and 100 mg.kg⁻¹day⁻¹) or the reference medication atropine (0.2 mg.kg⁻¹day⁻¹), and Hes-7-RGlc alone (50 and 10 mg.kg⁻¹day⁻¹) were the seven groups investigated. DVDP was administered orally for seven days, followed by fourteen days of Hes-7-RGlc therapy. Then the rats were euthanized, and their blood and hearts were removed. Hes-7-RGlc chemotherapy substantially (p<0.05) restored DVDP-elicited dynamics in plasma and cardiac/myocardium creatine kinase isoenzyme (CK-MB), major lipids (cholesterol, triacylglycerol, and phospholipids), electrolytes (Na⁺, K⁺, Ca²⁺, Mg²⁺, Cl⁻), and total protein. Hes-7-RGlc remedy decidedly (p<0.05) abolished DDVP-stimulated amplification in the cardiac concentration of H₂O₂, NO and malondialdehyde; annulled DVDP-educed decreases in heart GSH levels, activities of GST, SOD, catalase, and glutathione peroxidase, ion transporters (Na⁺/K⁺-ATPase and Ca²⁺/Mg²⁺-ATPase), ALT, AST, ALP, and LDH-1. Collectively, Hes-7-RGlc can be advocated as a natural supplementary candidate and blocker of DVDP-provoked heart deficits via its capacity to reverse disruptions of electrolytes, ion pumps, redox status, and lipid homeostasis.

"Catch-and-feed": Janus catalytic flow-through membrane enables highly efficient removal of micropollutants in water

Micropollutants, due to their low concentrations, exceptional chemical stability, and profound toxicity, present a significant challenge in water treatment. While electrocatalysis and photocatalysis have shown promise as potential water purification techniques, their inherent limitations in mass transfer often result in elevated energy requirements and suboptimal efficiency. In this study, a Janus catalytic flow-through membrane (JCFM) was utilized to successfully remove two notorious micropollutants dichlorvos (DDVP) and azoxystrobin (AZX) from water based on the "catch-and-feed" strategy. This membrane adopts a ``sandwich'' configuration, comprising platinum-modified reduced titanium (Pt@rTO) as the electrocatalytic layer, porous titanium (Ti) as the current collector, and rTO as the photocatalytic layer. The JCFM exhibited remarkable performance, maintaining an •OH energy conversion efficiency of up to 20.12 nM and displaying catalytic activity (kJCFM = 6.97 × 10-4 s-1) in degrading AZX far superior to that of photocatalysis (kPC = 9.51 × 10-5 s-1) or electrocatalysis (kEC = 9.89 × 10-5 s-1) alone. It is evidenced that the Pt@rTO layer efficiently generates reactive oxygen species (ROS), which, along with the micropollutants, flow through the JCFM ("feed"), which strengthens mass transfer and facilitates efficient reactions within the confined space ("catch"). The ROSs then seep through the rTO layer, where they are reactivated by UV light radiation. The mechanism and the alternative reaction pathway of DDVP and AZX has also been proposed. In sequential testing, the JCFM achieved continuous and energy-efficient removal of micropollutants, exceeding 97.5 % over 200 h. The scale-up application of this technology has proven effective in the treatment of secondary biochemical effluent from municipal sewage, coking wastewater, and landfill leachate, achieving the concurrent degradation of various micropollutants.

The Degradation and Migration of Cyclanilide in Soil and Sediment in China

The environmental fate of a plant growth regulator cyclanilide was studied in this paper. The degradation, adsorption, and migration behaviors of cyclanilide were detailly measured in the laboratory. The results showed that the DT50 of cyclanilide degradation in the Jiangxi red, Taihu paddy, Changshu wushan, Shaanxi tide, and Dongbei black soils was 42.3 d, 31.9 d, 14.4 d, 30.4 d as well as 27.4 d under aerobic conditions and 32.3 d, 37.4 d, 29.3 d, 48.9 d as well as 27.0 d under water anaerobic conditions, respectively, with the main metabolite being 2,4-dichloroaniline (2,4-D). The DT50 of 2,4-D ranged from 5.26 to 27.1 days under aerobic conditions, and from 10.6 to 54.1 days under anaerobic conditions. The adsorption of cyclanilide by the soils was well fitted by the empirical linear adsorption isotherm, and the adsorption constant (Kd, H) values in the Jiangxi red, Taihu paddy, Changshu wushan, Shaanxi tide, and Dongbei black soils were 7.08, 4.49, 4.05, 3.20, and 1.41, respectively. The results of a mobility test showed that cyclanilide had strong mobility in the most test soils. Furthermore, soil pH is the dominant element affecting the adsorption of cyclanilide in the soils. Under aerobic environment, the DT50 of total cyclanilide in river and lake water-sediment systems were 30.7 d and 34.0 d, respectively; under anaerobic environment, their DT50 were 30.8 d and 31.4 d, respectively. In water-sediment systems, 2,4-D mainly exists in aqueous phase and the DT50 ranged from 5.23 to 8.76 days. This work demonstrated that cyclanilide has the potential risk to contaminate environment and attention should be paid to its application.

Sexual dysfunction in dichlorvos-exposed male Wistar rat is ameliorated by curcumin and associated with the upregulation of testosterone

Dichlorvos is an organophosphate pesticide that is commonly used for agricultural and domestic control of pests and insects. Despite its usefulness, it exerts reproductive toxicity and induces male sexual dysfunction. On the other hand, curcumin has been reported to improve sexual dysfunction. However, till date, no study has reported the impact of curcumin on dichlorvos-induced sexual dysfunction. This study investigated the effect and associated mechanism of curcumin on dichlorvos-induced sexual dysfunction. Thirty-two male Wistar rats were randomized into four groups; the control (1 mL of olive oil), curcumin-treated (100 mg/kg), DDVP-treated (98.54 g/m3 of dichlorvos by inhalation), and DDVP + Curcumin-treated. Dichlorvos induced sexual dysfunction as depicted by reduced motivation to mate (8.38 ± 0.18 vs. 4.00 ± 0.33, P < 0.0001), prolonged latencies (46.63 ± 1.30 vs. 98.75 ± 1.32, P < 0.0001) and reduced frequencies of mount (14.88 ± 0.52 vs. 8.63 ± 0.38), intromission (9.38 ± 0.50 vs. 3.75 ± 0.31, P < 0.0001), and ejaculation (7.63 ± 0.38 vs. 1.50 ± 0.19, P < 0.0001). These findings were accompanied by suppression of hypothalamic-pituitary-testicular axis, evidenced by marked reductions in circulating FSH (60.00 ± 1.04 vs. 21.13 ± 0.52, P < 0.0001), LH (46.38 ± 1.38 vs. 19.00 ± 0.46, P < 0.0001), and testosterone (6.01 ± 0.50 vs. 0.74 ± 0.05, P < 0.0001). Nonetheless, the administration of curcumin in dichlorvos-exposed rats significantly attenuated dichlorvos-induced sexual dysfunction by improving the assessed indices of male sexual act. Also, curcumin significantly increased serum levels of FSH (21.13 ± 0.52 vs. 47.25 ± 0.10, P < 0.0001), LH (19.00 ± 0.46 vs. 43.00 ± 1.49), and testosterone (0.74 ± 0.05 vs. 3.98 ± 0.08, P < 0.0001). This study revealed that curcumin attenuated dichlorvos-induced sexual dysfunction by activating the hypothalamic-pituitary-testicular axis and upregulating circulating testosterone.

Critical review on organophosphate esters in water environment: Occurrence, health hazards and removal technologies

Organophosphate esters (OPEs), which are phosphoric acid ester derivatives, are anthropogenic substances that are widely used in commerce. Nevertheless, there is growing public concern about these ubiquitous contaminants, which are frequently detected in contaminated water sources. OPEs are mostly emitted by industrial operations, and the primary routes of human exposure to OPEs include food intake and dermal absorption. Because of their negative effects on both human health and the environment, it is clear that innovative methods are needed to facilitate their eradication. In this study, we present a comprehensive overview of the existing characteristics and origins of OPEs, their possible impacts on human health, and the merits, drawbacks, and future possibilities of contemporary sophisticated remediation methods. Current advanced remediation approaches for OPEs include adsorption, degradation (advanced oxidation, advanced reduction, and redox technology), membrane filtration, and municipal wastewater treatment plants, degradation and adsorption are the most promising removal technologies. Meanwhile, we proposed potential areas for future research (appropriate management approaches, exploring the combination treatment process, economic factors, and potential for secondary pollution). Collectively, this work gives a comprehensive understanding of OPEs, providing useful insights for future research on OPEs pollution.

Development of a Green Single Drop Microextraction Based on Deep Eutectic Solvent and HPLC-UV for Trace Residue Analysis of Three Frequent-Used Pesticides

Background

A green sample preparation method named deep eutectic solvent-based single drop microextraction (DES-SDME) was developed and optimized for determining trace metribuzin, dichlorvos, and fenthion.

Methods

Two hundred seventy experimental runs were performed, and the optimal values of the five influential factors in the DES-SDME method were determined. The design of the study was based on one factor at a time and the peak area of high-performance liquid chromatography was used as a benchmark for comparing analysis results.

Results

After optimizing the effective factors, the linearity range, detection limit and quantification limit of the method were determined by drawing calibration curves for the studied analytes.

Conclusion

The results indicated the success of the developed method in obtaining acceptable figures of merit as a green preparation method with accuracy and precision.

New roles for Bacillus thuringiensis in the removal of environmental pollutants

For a long time, the well-known Gram-positive bacterium Bacillus thuringiensis (Bt) has been extensively studied and developed as a biological insecticide for Lepidoptera and Coleoptera pests due to its ability to secrete a large number of specific insecticidal proteins. In recent years, studies have found that Bt strains can also potentially biodegrade residual pollutants in the environment. Many researchers have isolated Bt strains from multiple sites polluted by exogenous compounds and characterized and identified their xenobiotic-degrading potential. Furthermore, its pathway for degradation was also investigated at molecular level, and a number of major genes/enzymes responsible for degradation have been explored. At present, a variety of xenobiotics involved in degradation in Bt have been reported, including inorganic pollutants (used in the field of heavy metal biosorption and recovery and precious metal recovery and regeneration), pesticides (chlorpyrifos, cypermethrin, 2,2-dichloropropionic acid, etc.), organic tin, petroleum and polycyclic aromatic hydrocarbons, reactive dyes (congo red, methyl orange, methyl blue, etc.), and ibuprofen, among others. In this paper, the biodegrading ability of Bt is reviewed according to the categories of related pollutants, so as to emphasize that Bt is a powerful agent for removing environmental pollutants.

Metals (Ga, In) decorated fullerenes as nanosensors for the adsorption of 2,2-dichlorovinyldimethylphosphate agrochemical based pollutant

Owing to the fact that the use of 2,2-dichlorovinyldimethylphosphate (DDVP) as an agrochemical has become a matter of concern due to its persistence and potential harm to the environment and human health. Detecting and addressing DDVP contamination is crucial to protect human health and mitigate ecological impacts. Hence, this study focuses on harnessing the properties of fullerene (C60) carbon materials, known for their biological activities and high importance, to develop an efficient sensor for DDVP. Additionally, the sensor's performance is enhanced by doping it with gallium (Ga) and indium (In) metals to investigate the sensing and trapping capabilities of DDVP molecules. The detection of DDVP is carefully examined using first-principles density functional theory (DFT) at the Def2svp/B3LYP-GD3(BJ) level of theory, specifically analyzing the adsorption of DDVP at the chlorine (Cl) and oxygen (O) sites. The adsorption energies at the Cl site were determined as - 57.894 kJ/mol, - 78.107 kJ/mol, and - 99.901 kJ/mol for Cl_DDVP@C60, Cl_DDVP@Ga@C60, and Cl_DDVP@In@C60 interactions, respectively. At the O site, the adsorption energies were found to be - 54.400 kJ/mol, - 114.060 kJ/mol, and - 114.056 kJ/mol for O_DDVP@C60, O_DDVP@Ga@C60, and O_DDVP@In@C60, respectively. The adsorption energy analysis highlights the chemisorption strength between the surfaces and the DDVP molecule at the Cl and O sites of adsorption, indicating that the O adsorption site exhibits higher adsorption energy, which is more favorable according to the thermodynamics analysis. Thermodynamic parameters (∆H and ∆G) obtained from this adsorption site suggest considerable stability and indicate a spontaneous reaction in the order O_DDVP@Ga@C60 > O_DDVP@In@C60 > O_DDVP@C60. These findings demonstrate that the metal-decorated surfaces adsorbed on the oxygen (O) site of the biomolecule offer high sensitivity for detecting the organophosphate molecule DDVP.

Membrane technology for pesticide removal from aquatic environment: Status quo and way forward

The noxious side effects of pesticides on human health and environment have prompted the search of effective and reliable treatment techniques for pesticide removal. The removal of pesticides can be accomplished through physical, chemical and biologicals. Physical approaches such as filtration and adsorption are prevailing pesticide removal strategies on account of their effectiveness and ease of operation. Membrane-based filtration technology has been recognized as a promising water and wastewater treatment approach that can be used for a wide range of organic micropollutants including pesticides. Nanofiltration (NF), reverse osmosis (RO) and forward osmosis (FO) have been increasingly explored for pesticide removal from aquatic environment owing to their versatility and high treatment efficiencies. This review looks into the remedial strategies of pesticides from aqueous environment using membrane-based processes. The potentials and applications of three prevailing membrane processes, namely NF, RO and FO for the treatment of pesticide-containing wastewater are discussed in terms of the development of advanced membranes, separation mechanisms and system design. The challenges in regards to the practical implementation of membrane-based processes for pesticide remediation are identified. The corresponding research directions and way forward are highlighted. An in depth understanding of the pesticide nature, water chemistry and the pesticide-membrane interactions is the key to achieving high pesticide removal efficiency. The integration of membrane technology and conventional removal technologies represents a new dimension and the future direction for the treatment of wastewater containing recalcitrant pesticides.

Environmental Occurrence, Toxicity Concerns, and Degradation of Diazinon Using a Microbial System

Diazinon is an organophosphorus pesticide widely used to control cabbage insects, cotton aphids and underground pests. The continuous application of diazinon in agricultural activities has caused both ecological risk and biological hazards in the environment. Diazinon can be degraded via physical and chemical methods such as photocatalysis, adsorption and advanced oxidation. The microbial degradation of diazinon is found to be more effective than physicochemical methods for its complete clean-up from contaminated soil and water environments. The microbial strains belonging to Ochrobactrum sp., Stenotrophomonas sp., Lactobacillus brevis, Serratia marcescens, Aspergillus niger, Rhodotorula glutinis, and Rhodotorula rubra were found to be very promising for the ecofriendly removal of diazinon. The degradation pathways of diazinon and the fate of several metabolites were investigated. In addition, a variety of diazinon-degrading enzymes, such as hydrolase, acid phosphatase, laccase, cytochrome P450, and flavin monooxygenase were also discovered to play a crucial role in the biodegradation of diazinon. However, many unanswered questions still exist regarding the environmental fate and degradation mechanisms of this pesticide. The catalytic mechanisms responsible for enzymatic degradation remain unexplained, and ecotechnological techniques need to be applied to gain a comprehensive understanding of these issues. Hence, this review article provides in-depth information about the impact and toxicity of diazinon in living systems and discusses the developed ecotechnological remedial methods used for the effective biodegradation of diazinon in a contaminated environment.

Biodegradation of fipronil: current state of mechanisms of biodegradation and future perspectives

Fipronil is a broad-spectrum phenyl-pyrazole insecticide that is widely used in agriculture. However, in the environment, its residues are toxic to aquatic animals, crustaceans, bees, termites, rabbits, lizards, and humans, and it has been classified as a C carcinogen. Due to its residual environmental hazards, various effective approaches, such as adsorption, ozone oxidation, catalyst coupling, inorganic plasma degradation, and microbial degradation, have been developed. Biodegradation is deemed to be the most effective and environmentally friendly method, and several pure cultures of bacteria and fungi capable of degrading fipronil have been isolated and identified, including Streptomyces rochei, Paracoccus sp., Bacillus firmus, Bacillus thuringiensis, Bacillus spp., Stenotrophomonas acidaminiphila, and Aspergillus glaucus. The metabolic reactions of fipronil degradation appear to be the same in different bacteria and are mainly oxidation, reduction, photolysis, and hydrolysis. However, the enzymes and genes responsible for the degradation are somewhat different. The ligninolytic enzyme MnP, the cytochrome P450 enzyme, and esterase play key roles in different strains of bacteria and fungal. Many unanswered questions exist regarding the environmental fate and degradation mechanisms of this pesticide. The genes and enzymes responsible for biodegradation remain largely unexplained, and biomolecular techniques need to be applied in order to gain a comprehensive understanding of these issues. In this review, we summarize the literature on the degradation of fipronil, focusing on biodegradation pathways and identifying the main knowledge gaps that currently exist in order to inform future research. KEY POINTS: • Biodegradation is a powerful tool for the removal of fipronil. • Oxidation, reduction, photolysis, and hydrolysis play key roles in the degradation of fipronil. • Possible biochemical pathways of fipronil in the environment are described.

Emerging Strategies for the Bioremediation of the Phenylurea Herbicide Diuron

Diuron (DUR) is a phenylurea herbicide widely used for the effective control of most annual and perennial weeds in farming areas. The extensive use of DUR has led to its widespread presence in soil, sediment, and aquatic environments, which poses a threat to non-target crops, animals, humans, and ecosystems. Therefore, the removal of DUR from contaminated environments has been a hot topic for researchers in recent decades. Bioremediation seldom leaves harmful intermediate metabolites and is emerging as the most effective and eco-friendly strategy for removing DUR from the environment. Microorganisms, such as bacteria, fungi, and actinomycetes, can use DUR as their sole source of carbon. Some of them have been isolated, including organisms from the bacterial genera Arthrobacter, Bacillus, Vagococcus, Burkholderia, Micrococcus, Stenotrophomonas, and Pseudomonas and fungal genera Aspergillus, Pycnoporus, Pluteus, Trametes, Neurospora, Cunninghamella, and Mortierella. A number of studies have investigated the toxicity and fate of DUR, its degradation pathways and metabolites, and DUR-degrading hydrolases and related genes. However, few reviews have focused on the microbial degradation and biochemical mechanisms of DUR. The common microbial degradation pathway for DUR is via transformation to 3,4-dichloroaniline, which is then metabolized through two different metabolic pathways: dehalogenation and hydroxylation, the products of which are further degraded via cooperative metabolism. Microbial degradation hydrolases, including PuhA, PuhB, LibA, HylA, Phh, Mhh, and LahB, provide new knowledge about the underlying pathways governing DUR metabolism. The present review summarizes the state-of-the-art knowledge regarding (1) the environmental occurrence and toxicity of DUR, (2) newly isolated and identified DUR-degrading microbes and their enzymes/genes, and (3) the bioremediation of DUR in soil and water environments. This review further updates the recent knowledge on bioremediation strategies with a focus on the metabolic pathways and molecular mechanisms involved in the bioremediation of DUR.