Search Results (51)

Pesticides remain indispensable for modern agriculture, yet their persistence in soil poses serious ecological and human-health risks through bioaccumulation, groundwater contamination, and impacts on non-target organisms. Although extensive research exists on pesticide degradation, most reviews separate biochemical pathways, environmental controls, and applied bioremediation strategies, limiting the ability to predict real-world field performance. This review integrates mechanistic enzymology, soil ecological responses, quantitative degradation kinetics, and emerging synthetic biology innovations into one unified framework. Soil bacteria including Pseudomonas, Bacillus, Rhodococcus, and Arthrobacter degrade organophosphates, carbamates, triazines, neonicotinoids, pyrethroids, and organochlorines through hydrolysis, oxidation, nitroreduction, and ring-cleavage pathways, often supported by plasmid-encoded genes and horizontal gene transfer. Bioaugmented systems typically achieve 70 to 95 percent removal within 10 to 30 days, with highly efficient cases such as Pseudomonas putida KT2440 removing 96 percent chlorpyrifos in 5 days, Rhodococcus koreensis mineralizing 98 percent endosulfan in 7 days, and Arthrobacter sp. AD26 degrading 95 percent atrazine in 72 h. Field-scale Azotobacter–Pseudomonas consortia have reduced chlorpyrifos from 25 mg kg⁻¹ to less than 1 mg kg⁻¹ within 30 days. Environmental conditions strongly influence degradation efficiency. Acidic soils increase pyrethroid half-lives by two to three times, anaerobic conditions can extend pesticide persistence from months to years, and drought or low organic matter reduces microbial activity by 60 to 80 percent, increasing neonicotinoid DT₅₀ to more than 1000 days. Advances in omics, metagenomics, kinetic assays, and synthetic biology now enable engineered strains and synthetic consortia capable of more than 90 percent mineralization within 7 to 21 days. By linking molecular mechanisms, ecological constraints, quantitative outcomes, and emerging biotechnologies, this review provides a predictive roadmap for climate-resilient, scalable, and sustainable bioremediation strategies. Full article

Exploration of new niches for microorganisms capable of degrading recalcitrant molecules is still required. We hypothesized that the gut microbiota associated with the field S. frugiperda population carries pesticide-degrading bacteria that would enhance the host’s ability to metabolize pesticides. Three strategies were implemented to address this principle: (i) isolation and identification of chlorpyrifos-degrading gut bacteria from field-collected S. frugiperda larvae; (ii) evaluation of chlorpyrifos biodegradation capacity through in vitro assays; and (iii) assessment of the impact of specific bacterial taxa capable of degrading chlorpyrifos directly within the gut. In this study, we successfully isolated four chlorpyrifos-degrading gut bacterial isolates from a field-collected population of S. frugiperda. These isolates were identified using 16S rDNA sequencing as Klebsiella quasipneumoniae strain 60D (PP504878), Klebsiella pneumoniae strain 64D (PP504879), Klebsiella pneumoniae strain 66D (PP504880), and Klebsiella pneumoniae strain 71D (PP504881). In vitro chlorpyrifos degradation assays revealed that all isolates exhibited strong degradative capacities, with Klebsiella pneumoniae strain 64D achieving the highest degradation rate, 80.38%, after one day of inoculation. In contrast, in vivo chlorpyrifos biodegradation assessment demonstrated a clear protective effect of gut bacteria on host survival. Among the mono-associated groups, larvae colonized with Klebsiella pneumoniae strain 66D exhibited the most pronounced reduction in mortality by 19.16-fold compared to antibiotic-treated larvae following exposure to chlorpyrifos suspension. Full article

Widespread use of pesticides in agriculture causes adverse impacts on non-target organisms and environmental pollution. Efficient and sustainable pesticide removal alternatives must be developed to reduce pesticide environmental impacts. Recently, bioremediation based on immobilized microorganisms has been proposed as an environmentally friendly and cost-effective approach for pesticide degradation in water. Agro-industrial wastes are produced in large quantities in crop fields; their high availability, low cost, and potential for reuse make them ideal support materials for microbial immobilization. This systematic review, conducted through the PRISM 2020 methodology, compiles recent research on using agro-industrial waste to immobilize microorganisms for pesticide degradation. The identified studies highlight corn straw as the most studied agro-industrial waste, while the organophosphorus insecticides, chlorpyrifos, and methyl parathion were the most representative pesticides; in the identified studies, pesticide degradation was conducted mainly by bacteria of the Acinetobacter, Bacillus, and Pseudomonas genera. Overall, microbial immobilization significantly enhanced pesticide degradation, rendering it a viable bioremediation strategy for pesticide-contaminated water. Full article

In this work, OP- and OC-degrading bacteria were isolated from agricultural soil samples taken in the department of Bolivar, Colombia. The objective of this research was to degrade organochlorine and organophosphorus pesticides using bacterial colonies native to agricultural soils. Two bacterial colonies were isolated from the soil samples, which showed a higher degree of adaptation to media contaminated with the pesticide mixtures. They were identified by biochemical tests using BBL Crystal kits, and, subsequently, their 16S rDNA was sequenced using the PCR technique. Bacterial growth was studied by the OD index, taking absorbance readings on a UV-VIS spectrophotometer at 600 nm, at the 0.5 McFarland scale, and quantification of pesticide degradation was studied by GC–MS. The colonies identified were Bacillus cereus and Paenibacillus lautus. B. cereus isolates were exposed to the OPs malathion, chlorpyrifos, and coumaphos [80 mg·L⁻¹], degrading at rates of 52.4%, 78.8% and 79.5%, respectively, after 12 days of incubation in liquid medium at pH = 7.0 ± 0.2 and 37 °C. Furthermore, P. lautus isolates exposed to the OCs lindane, metolachlor, endrin, and p,p′-DDT [80 mg·L⁻¹] degraded at rates of 64.0%, 60.8%, 55.7% and 65.1% under the same conditions of temperature, pH, and incubation time. These results show that B. cereus and P. lautus might be useful for cleaning up environments that have been polluted by OPs and OCs. Full article

The increasing presence of pollutants, including pharmaceuticals and pesticides, in water resources necessitates the development of effective remediation technologies. Zeolites are promising agents for pollutant removal due to their high surface area, ion-exchange capacity, natural abundance, and diverse tailorable porous structures. This review focuses on the efficient application of modified zeolites and mesoporous materials as photocatalysts and adsorbents for removing contaminants from water bodies. The adsorption and photodegradation of pesticides and selected non-steroidal anti-inflammatory drugs and antibiotics on various zeolites reveal optimal adsorption and degradation conditions for each pollutant. In most reported studies, higher SiO₂/Al₂O₃ ratio zeolites exhibited improved adsorption, and thus photodegradation activities, due to increased hydrophobicity and lower negative charge. For example, SBA-15 demonstrated high efficiency in removing diclofenac, ibuprofen, and ketoprofen from water in acidic conditions. Metal doped into the zeolite framework was found to be a very active catalyst for the photodegradation of organic pollutants, including pesticides, pharmaceuticals, and industrial wastes. It is shown that the photocatalytic activity depends on the zeolite-type, metal dopant, metal content, zeolite pore structure, and the energy of the irradiation source. Faujasite-type Y zeolites combined with ozone achieved up to 95% micropollutant degradation. Bentonite modified with cellulosic biopolymers effectively removed pesticides such as atrazine and chlorpyrifos, while titanium and/or silver-doped zeolites showed strong catalytic activity in degrading carbamates, highlighting their environmental application potential. Full article

For the first time, a novel catalyst named Dy₂EuSbO₇ was successfully synthesized via the high-temperature solid-state sintering method (HTSSM). Dy₂EuSbO₇/ZnBiDyO₄ heterojunction photocatalyst (DZHP) was fabricated through the HTSSM for degrading chlorpyrifos (CPS) in the pesticide wastewater under visible light irradiation (VSLID). Under VSLID, DZHP could effectively degrade CPS in pesticide wastewater. The experimental outcomes suggested that the kinetic curve with the Dy₂EuSbO₇/ZnBiDyO₄ heterojunction (DZH) as a photocatalyst for the reduction of CPS under VSLID conformed to the first-order kinetics (FOKT). After VSLID of 156 min, the photocatalytic degradation (PTD) removal rate of CPS using DZH as photocatalyst was 1.12 times, 1.21 times, or 2.96 times that using Dy₂EuSbO₇ as a photocatalyst, ZnBiDyO₄ as a photocatalyst, or nitrogen-doped titanium dioxide as a photocatalyst. After VSLID of 156 min for four cycle degradation tests (FCDTS) with DZH as a photocatalyst, the removal rate of CPS reached 98.78%, 97.66%, 96.59%, and 95.69%, respectively. Above results indicated that the DZHP possessed high stability. Experiments with the addition of trapping agents showed that hydroxyl radicals (•OH) owned the strongest oxidative removal ability for degrading CPS compared with superoxide anions (•O₂⁻) or holes (h⁺). The oxidation capacity of three oxidation radicals for eliminating CPS was ranked in the ascending order as follows: h⁺ < •OH < •O₂⁻. Lastly, the possible degradation pathway and degradation mechanism of CPS were discussed in detail. A visible light responsive heterojunction catalyst with high catalytic activity and a photocatalytic reaction system which were capable of efficiently removing toxic organic pollutants from pesticide wastewater were obtained. Full article

This study utilizes Mentha piperita (MI) for the first time to investigate the uptake and translocation of chlorpyrifos (CPF; 10 µg g⁻¹) from soil, introducing a new approach to improve the efficacy of this technique, which includes using biosurfactants (Bacillus subtilis and Pseudomonas aeruginosa) at 10⁷ CFU/mL to degrade CPF under greenhouse conditions. Moreover, antioxidant enzymes, including superoxide dismutase (SOD) and peroxidase (Prx), and oxidative stress due to hydrogen peroxide (H₂O₂) and malondialdehyde (MDA) in MI roots and leaves were evaluated under CPF stress. Our results demonstrated that amending soil with MI and B. subtilis followed by P. aeruginosa significantly reduced CPF levels in the soil (p > 0.05) and enhanced CPF concentrations in MI roots and leaves after 1, 3, 7, 10, and 14 days of the experiment. Furthermore, CPF showed its longest half-life (t_1/2) in soil contaminated solely with CPF, lasting 15.36 days. Conversely, its shortest half-life occurred in soil contaminated with CPF and treated with MI along with B. subtilis, lasting 4.65 days. Soil contaminated with CPF and treated with MI and P. aeruginosa showed a half-life of 7.98 days. The half-life (t_1/2) of CPF-contaminated soil with MI alone was 11.41 days. A batch equilibrium technique showed that B. subtilis is better than P. aeruginosa for eliminating CPF from soil in In vitro experiments. Notably, CPF-polluted soil treated with coadministration of MI and the tested bacteria improved the activities of SOD and Prx and reduced H₂O₂ and MDA compared with CPF-polluted soil treated with MI alone. Our findings demonstrated that using B. subtilis and P. aeruginosa as biosurfactants to augment phytoremediation represents a commendable strategy for enhancing the remediation of CPF contamination in affected sites while reducing the existence of harmful pesticide remnants in crop plants. Full article

In this study, the degradation system of Shewanella oneidensis MR-1 and goethite was constructed with chlorpyrifos as the target contaminant. The effects of initial pH, contaminant concentration, and temperature on the removal rate of chlorpyrifos during the degradation process were investigated. The experimental conditions were optimized by response surface methodology with a Box–Behnken design (BBD). The results show that the removal rate of chlorpyrifos is 75.71% at pH = 6.86, an initial concentration of 19.18 mg·L⁻¹, and a temperature of 30.71 °C. LC-MS/MS analyses showed that the degradation products were C₄H₁₁O₃PS, C₇H₇Cl₃NO₄P, C₉H₁₁Cl₂NO₃PS, C₇H₇Cl₃NO₃PS, C₉H₁₁Cl₃NO₄P, C₄H₁₁O₂PS, and C₅H₂Cl₃NO. Presumably, the degradation pathways involved are: enzymatic degradation, hydrolysis, dealkylation, desulfur hydrolysis, and dechlorination. The findings of this study demonstrate the efficacy of the goethite/S. oneidensis MR-1 complex system in the removal of chlorpyrifos from water. Consequently, this research contributes to the establishment of a theoretical framework for the microbial remediation of organophosphorus pesticides in aqueous environments. Full article

Litsea martabanica root’s antioxidant and acetylcholinesterase (AChE) activity showed promise as a pesticide detoxification agent in our previous study. In addition to its root, leaves can help alleviate pesticide exposure, although there is limited scientific evidence supporting their efficacy. However, the use of roots in several countries, such as Thailand, could contribute to environmental degradation, as highland communities traditionally used leaves instead of roots. This study aims to evaluate the antioxidant activity and anti-pesticide potential of water extract from L. martabanica leaves through in vitro and in vivo investigations. In the in vitro study, L. martabanica water extract and its fractions demonstrated antioxidant activity and induced apoptosis in hepatic satellite cells. In the in vivo study, treatment with the leaf extract led to increased AChE activity, decreased malondialdehyde (MDA) levels, increased superoxide dismutase (SOD) levels, and reduced glutathione in chlorpyrifos-exposed rats. Histopathological examination revealed that chlorpyrifos-treated rats exhibited liver cell damage, while treatment with the water extract of L. martabanica exhibited a protective effect on the liver. In conclusion, L. martabanica water extract exhibited antioxidant activity, enhanced AChE activity, and improved histopathological abnormalities in the liver. Full article

Persulfate-based advanced oxidation process has been proven to be a promising method for the toxic pesticide chlorpyrifos (CPY) degradation in wastewater treatment. However, due to the limitation for the short-lived intermediates detection, a comprehensive understanding for the degradation pathway remains unclear. To address this issue, density functional theory was used to analyze the degradation mechanism of CPY at the M06-2X/6-311++G(3df,3pd)//M06-2X/6-31+G(d,p) level, and computational toxicology methods were employed to explore the toxicity of CPY and its degradation products. Results show that hydroxyl radicals (·OH) and sulfate radicals (SO₄^•−) initiate the degradation reactions by adding to the P=S bond and abstracting the H atom on the ethyl group, rather than undergoing α-elimination of the pyridine ring in the persulfate oxidation process. Moreover, the addition products were attracted and degraded by breaking the P–O bond, while the abstraction products were degraded through dealkylation reactions. The transformation products, including 3,5,6-trichloro-2-pyridynol, O,O-diethyl phosphorothioate, chlorpyrifos oxon, and acetaldehyde, obtained through theoretical calculations have been detected in previous experimental studies. The reaction rate constants of CPY with ·OH and SO₄^•− were 6.32 × 10⁸ and 9.14 × 10⁸ M⁻¹·s⁻¹ at room temperature, respectively, which was consistent with the experimental values of 4.42 × 10⁹ and 4.5 × 10⁹ M⁻¹ s⁻¹. Toxicity evaluation results indicated that the acute and chronic toxicity to aquatic organisms gradually decreased during the degradation process. However, some products still possess toxic or highly toxic levels, which may pose risks to human health. These research findings contribute to understanding the transformation behavior and risk assessment of CPY in practical wastewater treatment. Full article

Eu₂SmSbO₇ and ZnBiEuO₄ were synthesized for the first time using the hydrothermal method. Eu₂SmSbO₇/ZnBiEuO₄ heterojunction photocatalyst (EZHP) was synthesized for the first time using the solvothermal method. The crystal cell parameter of Eu₂SmSbO₇ was 10.5547 Å. The band gap width of Eu₂SmSbO₇ was measured and found to be 2.881 eV. The band gap width of ZnBiEuO₄ was measured and found to be 2.571 eV. EZHP efficiently degraded the pesticide chlorpyrifos under visible light irradiation (VLID). After VLID of 160 min, the conversion rate of the chlorpyrifos concentration reached 100%, while the conversion rate of the total organic carbon (TOC) concentration was 98.02% using EZHP. After VLID of 160 min, the photocatalytic degradation conversion rates of chlorpyrifos using EZHP were 1.13 times, 1.19 times, and 2.84 times those using Eu₂SmSbO₇, ZnBiEuO₄, and nitrogen-doped titanium dioxide (N-doped TiO₂), respectively. The photocatalytic activity could be ranked as follows: EZHP > Eu₂SmSbO₇ > ZnBiEuO₄ > N-doped TiO₂. The conversion rates of chlorpyrifos were 98.16%, 97.03%, 96.03%, and 95.06% for four cycles of experiments after VLID of 160 min using EZHP. This indicated that EZHP was stable and could be reused. In addition, the experiments with the addition of capture agents demonstrated that the oxidation removal ability of three oxidation free radicals for degrading chlorpyrifos obeyed the following order: hydroxyl radical > superoxide anion > holes. This study examined the intermediates of chlorpyrifos during the photocatalytic degradation of chlorpyrifos, and a degradation path was proposed, at the same time, the degradation mechanism of chlorpyrifos was revealed. This study provides a scientific basis for the development of efficient heterojunction photocatalysts. Full article

Chlorpyrifos (CP) is a globally used pesticide with acute toxicity. This work studied the photocatalytic degradation of CP using TiO₂, ZnO nanoparticles, and nanocomposites of TiO₂ and ZnO supported on SPIONs (SPION@SiO₂@TiO₂ and SPION@SiO₂@ZnO). The nanocomposites were synthesized by multi-step incipient wetness impregnation. The effects of the initial pH, catalyst type, and dose were evaluated. The nanocomposites of SPION@SiO₂@TiO₂ and SPION@SiO₂@ZnO showed higher CP photodegradation levels than free nanoparticles, reaching 95.6% and 82.3%, respectively, at pH 7. The findings indicate that iron oxide, as a support material for TiO₂ and ZnO, extended absorption edges and delayed the electron–hole recombination of the nanocomposites, improving their photocatalytic efficiency. At the same time, these nanocomposites, especially SPION@SiO₂@TiO₂, showed efficient degradation of 3,5,6-trichloropyridinol (TCP), one of the final metabolites of CP. The stability and reuse of this nanocomposite were also evaluated, with 74.6% efficiency found after six cycles. Therefore, this nanomaterial represents an eco-friendly, reusable, and effective alternative for the degradation of chlorpyrifos in wastewater treatment. Full article

To investigate the effect of pesticide use on surface water, the concentration and distribution characteristics of 57 pesticides and 3 degradation products were analyzed in the farmland soil and surface water in the Xingkai Lake area, including water from paddy fields, drainages and the Xingkai Lake, in Heilongjiang Province, China. Forty-three pesticides and three degradation products were detected in farmland soil. In dry field (corn and soybean field) soil, the main detected pesticides were atrazine and acetochlor with mean concentrations of 26.09 ng·g⁻¹ and 49.08 ng·g⁻¹, respectively. In paddy field soil, oxadiazon, mefenacet and chlorpyrifos were the main detected pesticides with mean concentrations of 14.32 ng·g⁻¹, 78.60 ng·g⁻¹ and 20.03 ng·g⁻¹, respectively. In the surrounding water, including water from paddy fields, drainages and Xingkai Lake, the total concentrations of contaminants detected in the water samples ranged from 71.19 ng·L⁻¹ to 10,145.76 ng·L⁻¹. Of the three sampling periods, the mean concentration of contaminants in the water exhibited its peak during the vegetative period. In the analysis of the drainage water, the primary pesticides detected were atrazine, acetochlor and buprofezin with mean concentrations of 354.83 ng·L⁻¹, 109.09 ng·L⁻¹ and 254.56 ng·L⁻¹, respectively. Atrazine, simetryn, buprofezin and isoprothiolane were the main pesticides detected in Xingkai Lake water, with the mean concentrations of 222.35 ng·L⁻¹, 112.76 ng·L⁻¹, 301.87 ng·L⁻¹ and 138.02 ng·L⁻¹, respectively. The concentrations of contaminants could be correlated with drainage, Da Xingkai Lake and Xiao Xingkai Lake water (ρ > 0.8) suggested that the source of these contaminants in drainage and Xingkai Lake water could be the same. The maximum potentially affected fraction (PAF) values of atrazine, chlorpyrifos and prometryn were higher than 5% in Xingkai Lake water, resulting in high ecological risks. Full article

A groundbreaking photocatalytic nanomaterial, Dy₂NdSbO₇, was fabricated smoothly using the hydrothermal synthesis technique for the first time. Apart from that, Dy₂NdSbO₇/Bi₂WO₆ heterojunction photocatalyst (DBHP) was initially fabricated using the solvothermal fabrication technique. X-ray diffractometer, Fourier-transform infrared spectrometer, Raman spectrometer, UV-visible spectrophotometer, X-ray photoelectron spectrometer, inductively coupled plasma optical emission spectrometer, transmission electron microscope, and X-ray energy dispersive spectroscopy have been applied to evaluate and investigate the thetastructure, morphology, and physicochemical properties of synthesized samples. The results confirmed that the pyrochlore-type crystal structures of Dy₂NdSbO₇ belonged to the Fd3m space group with the cubic crystal system and the β-pyrochlore-type crystal structures of Bi₂WO₆ which belonged to the Pca21 space group with orthorhombic crystal system. Under visible light exposure for 155 min (VLP-155min) using DBHP in the capacity of the photocatalytic nanomaterial, the removal efficiency of chlorpyrifos (CPS) saturation reached 100%. Comparison of CPS removal efficiency after VLP-155min revealed that DBHP exhibited higher removal efficiency than Dy₂NdSbO₇, Bi₂WO₆, or N-doped TiO₂ photocatalyst, with removal efficiency 1.15 times, 1.23 times, or 2.55 times higher, respectively. Furthermore, the oxidizing capability of free radicals was investigated using trapping agents. Results demonstrated that superoxide anions exhibited the strongest oxidative capability, followed by hydroxyl radicals and holes. The results presented in this study lay a robust groundwork for future investigations and advancements in the field of highly efficient heterostructure material. These findings have significant implications for the development of environmental remediation strategies and provide valuable insights into sustainable solutions for addressing CPS contamination. Full article

This study investigates the degradation characteristics of chlorpyrifos under individual exposure and compound exposure to multiple pesticides in both traditional constructed wetlands and electrochemically constructed wetland coupled systems, while also analyzing the microbial communities within the systems using high-throughput sequencing technology. The results show that the electric field can enhance the degradation performance of the system. The degradation effect of the coupled electrochemically constructed wetland coupled system is better than that of the traditional constructed wetland, while the compound exposure to multiple pesticides inhibits the degradation efficiency. Under the influence of pesticides, the diversity of microbial communities decreases towards the end of the system operation, and the electrochemically constructed wetland coupled system exhibits lower diversity compared to the traditional constructed wetland. Proteobacteria is the dominant phylum under compound exposure to multiple pesticides, while Firmicutes, Fusobacteria, Verrucomicrobia, Aeromonas, and Methylophilus are the dominant electrochemically active phyla and genera in the electrochemically constructed wetland coupled system. The impact of pesticides and the electric field results in a decrease in amino acid metabolism and carbohydrate metabolism functions, while membrane transport functions increase. The compound exposure to multiple pesticides has a more significant impact on the microbial community structure and functionality than the electric field. The results also lay a theoretical foundation for the expansion of pesticide degradation technology and constructed wetland treatment technology to new fields, which is of great significance in realizing the “zero direct discharge” of agricultural production wastewater, solving the problem of agricultural non-point source pollution and ensuring the availability of agricultural production. Full article