Degradation Of Chlorpyrifos Research Articles

Enhanced solar light photocatalytic performance of Fe-ZnO in the presence of H2O2, S2O82−, and HSO5− for degradation of chlorpyrifos from agricultural wastes: Toxicities investigation

This study reported Fe doped zinc oxide (Fe-ZnO) synthesis to degrade chlorpyrifos (CPY), a highly toxic organophosphate pesticide and important sources of agricultural wastes. Fourier transform infrared, X-ray diffraction, scanning electron microscope, and energy-dispersive X-ray spectroscopic analyses showed successful formation of the Fe-ZnO with highly crystalline and amorphous nature. Water collected from agricultural wastes were treated with Fe-ZnO and the results showed 67% degradation of CPY by Fe-ZnO versus 39% by ZnO at 140 min treatment time. Detail mechanism involving reactive oxygen species production from solar light activated Fe-ZnO and their role in degradation of CPY was assessed. Use of H2O2, peroxydisulfate (S2O82−) and peroxymonosulfate (HSO5−) with Fe-ZnO under solar irradiation promoted removal of CPY. The peroxides yielded hydroxyl (OH) and sulfate radical (▪) under solar irradiation mediated by Fe-ZnO. Effects of several parameters including concentration of pollutant and oxidants, pH, co-existing ions, and presence of natural organic matter on CPY degradation were studied. Among peroxides, HSO5− revealed to provide better performance. The prepared Fe-ZnO showed high reusability and greater mineralization of CPY. The GC-MS analysis showed degradation of CPY resulted into several transformation products (TPs). Toxicity analysis of CPY as well as its TPs was performed and the formation of non-toxic acetate imply greater capability of the treatment technology.

Combined biostimulation and bioaugmentation for chlorpyrifos degradation in laboratory microcosms.

The online version contains supplementary material available at 10.1007/s13205-021-02980-9.

Plant-microbial remediation of chlorpyrifos contaminated soil

With the development of modern agriculture, the pollution caused by the use of chemical fertilizers and pesticides has become a serious problem, posing a threat to human health and the living environment. The remediation of plant microorganisms has been seen as an economical, effective, and eco-friendly method of cleaning up soils contaminated with organophosphorus pesticides. In this study, white-rot fungi were immobilized by adsorption method, a plant-microbial remediation met was established. The data results show that after 30 days, the combined remediation system for corn microbes increased the rate of chlorpyrifos degradation by 18% compared to the single remediation of the plant, and the rate of combined remediation of ryegrass microbes increased by 23%. The effect of CPF content in soil on the combined remediation is mainly reflected in the significant difference in the number of microorganisms (P < 0.05). In this article, plant-microbial remediation were applied to soil contaminated by CPF, which provides a new idea for the remediation of pesticide-contaminated soil. Combined bioremediation may be a better alternative to mitigate the impact of high pollution on microorganisms at different pollutant concentrations compared to single microbial remediation or phytoremediation.

Estimation of residue degradation of cypermethrin and chlorpyrifos in brinjal, tomato and cauliflower under supervised field trial

A study was carried out to detect and estimate the residue of cypermethrin and chlorpyrifos in brinjal, tomato and cauliflower using Gas Chromatography (GC) coupled with Electron Capture Detector (ECD) and Flame Thermionic Detector (FTD). Three supervised field trials were conducted and sprayed with the recommended dose of cypermethrin (1 ml/L of water) and chlorpyrifos (3 ml/L of water) in three vegetables by knapsack sprayer. Samples were collected at 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11 days after spray (DAS). The quantity of cypermethrin residue was above EU-MRLs (Maximum Residue Limit set by European Union) up to 4 DAS with 0.538 mg/kg in cauliflower; 3 DAS with 0.508 mg/kg in brinjal and 0.695 mg/kg in tomato. The quantity decreased down 0.328-0.019 mg/kg in cauliflower (4-9 DAS); 0.098-0.012 mg/kg (4-7 DAS) in brinjal and 0.458-0.022 mg/kg (4-7 DAS) in tomato which were below EU-MRLs (0.5 mg/kg). The quantity of chlorpyrifos residue was above EU-MRLs up to 9 DAS with 0.012 mg/kg in cauliflower but in brinjal and tomato, the detected quantities were above EU-MRLs up to 7 DAS with 0.029 mg/kg and 0.017 mg/kg residue. No residue was detected from brinjal and tomato samples collected at 8 DAS. But in cauliflower, no residue was detected at 10 days after spray. So, brinjal, tomato and cauliflower can be harvested safely at 4 DAS and 5 DAS for cypermethrin and in case of chlorpyrifos it was 8 DAS in brinjal and tomato and 10 DAS in cauliflower. Asian Australas. J. Biosci. Biotechnol. 2021, 6 (2), 60-67

Evaluation of Compost and Biochar to Mitigate Chlorpyrifos Pollution in Soil and Their Effect on Soil Enzyme Dynamics

The widespread environmental contamination of chlorpyrifos (CP) has raised human health concerns and necessitated cost-effective methods for its remediation. The current study evaluated the degradation behavior of CP in compost and biochar amended and unamended (original and sterilized) soils in an incubation trial. Two levels of CP (100 and 200 mg kg−1), compost and biochar (0.50%) were applied, and soil was collected at different time intervals. At the higher CP level (200 mg kg−1), CP a showed lower degradation rate (ƙ = 0.0102 mg kg−1 d−1) compared with a low CP level (ƙ = 0.0173 mg kg−1 d−1). The half-lives of CP were 40 and 68 days for CP at 100 and 200 mg kg−1 in original soil, respectively, and increased to 94 and 141 days in sterilized soils. CP degradation was accelerated in compost amended soils, while suppressed in biochar amended soils. Lower half lives of 20 and 37 days were observed with compost application at CP 100 and 200 mg kg−1 doses, respectively. The activities of soil enzymes were considerably affected by the CP contamination and significantly recovered in compost and biochar amended soils. In conclusion, the application of organic amendments especially compost is an important strategy for the remediation of CP contaminated soil.

Biodegradation of chlorpyrifos by an optimized Bacillus consortium isolated from pesticide-contaminated soils of Kerala, India

The current study attempted to develop a bacterial consortium which can degrade chlorpyrifos pesticide efficiently. Five morphologically different bacterial strains, capable to tolerate high chlorpyrifos concentration, were isolated from pesticide-contaminated soil. Further, possible combinations of the isolates were formed and each combination was screened and chlorpyrifos degradation percentage and half-lives were calculated. The consortium CON11, comprising of four isolates (CP28, CP30, CP31, and CP34) showed the highest chlorpyrifos degradation. The individual independent variables of chlorpyrifos degradation by CON11 viz. temperature (°C), pH, incubation time (days) and pesticide concentration (ppm) were optimized using one-factor at-a-time experiments. The consortium isolates were then identified by the molecular tools 16S rRNA gene typing and the sequences were submitted to GenBank. The four bacterial isolates thus identified are Bacillus amyloliquefaciens CP28 (MH667455), Bacillus pumilus CP30 (MH667456), Bacillus marisflavi CP31 (MN715880), and Bacillus subtilis CP34 (MH667458). These isolates which comprise CON11 consortium could degrade 91% of 100 ppm chlorpyrifos after 6 days of incubation at 30 °C and pH 7 with a half-life of 1.73 days indicating the promising potential of the consortium, CON11, in the cleanup of chlorpyrifos contaminated sites.

Interactions of chlorpyrifos degradation and Cd removal in iron-carbon-based constructed wetlands for treating synthetic farmland wastewater

Pesticide and heavy metal contaminants, such as chlorpyrifos (CP) and cadmium (Cd) in farmland drainage had caused the water pollution and attracted extensive concerns around the world. The incorporation of zeolite-based iron-carbon (ZB-IC) into constructed wetlands (CWs) was prepared to simultaneously remove chlorpyrifos (CP) and cadmium (Cd) in farmland drainage, and the interaction of CP degradation and Cd removal was investigated. Laboratory simulated experiments were carried out in this study, and the results presented that the removal efficiencies of CP and Cd by ZB-IC coupled CWs (ZB–IC–CW) were 99.55% and 98.59%, respectively, which were much higher than that of the zeolite-based (ZB) CWs (CP = 92.99%; Cd = 63.54%). The removal mechanism of CP and Cd by ZB-IC substrate was mainly attributed to electron transfer, which occurred from iron corrosion and hydrogen generation process. In addition, CP could act as carbon source to promote denitrification process. Microbial analysis revealed that the relative abundances of CP-resistant bacteria (Firmicutes, Clostridia and Acetobacterium), Cd-resistant bacteria (Bacteroidetes) and denitrifying bacteria (Proteobacteria and Patescibacteria) were dramatically increased due to the addition of ZB-IC. The higher czcA gene and opd gene in ZB–IC–CW demonstrated that the addition of CP played a positive role in Cd removal, while Cd showed slightly affect to CP removal.

Identification of photodegradation product of organophosphorus pesticides and elucidation of transformation mechanism under simulated sunlight irradiation

Organophosphorus pesticides (OPs) are posing great threat to the environment and human health, due to their overuse and persistence in the environment. Photolysis has been established as an effective method to degrade OPs. The influence of pH value, the initial concentration of pesticides and the light source on the photolysis of two OPs, including chlorpyrifos and dimethoate, was investigated. The optimal reaction condition for OPs degradation was under pH 9, with xenon lamp as the light source, in which the photodegradation efficiencies of chlorpyrifos and dimethoate (500 mg/L) were 75.12% and 94.31%, respectively. The photodegradation products of chlorpyrifos and dimethoate were identified by GC-MS. Also, density functional theory (DFT) calculations were used to characterize the molecular properties of chlorpyrifos and dimethoate, as well as predicting potential photolysis reactions. Photodegradation mechanisms of chlorpyrifos and dimethoate were proposed, in which 3,5,6-trichloropyridinol (TCP), O,O-diethyl thiophosphate (DETP), 2,3,5-Trichloro-6-methoxypyridine (TMP) and O,O,S-trimethyl phosphorothioate were identified as the main products of chlorpyrifos degradation. Omethoate, O,O,S-trimethyl thiophosphorothioate, N-methyl-2-sulfanylacetamide, O,O,O-trimethyl thiophosphate, O,O,S-trimethylphosphorothiate, and O,O,O-trimethyl phosphoric ester as the main photodegradation products for dimethoate. The main degradation mechanisms included ring opening, cleavage, oxidation and demethylation. This work demonstrated the feasibility of combining chemical analysis with quantum chemical calculation in unraveling degradation mechanisms of OPs. Also, it is of great significance for evaluating the environmental fate of OPs in aquatic system and further environmental risk assessment.

Biodegradation of organophosphorus insecticide chlorpyrifos into a major fuel additive 2,4-bis(1,1 dimethylethyl) phenol using white-rot fungal strain Trametes hirsuta MTCC-1171

Biodegradation of chlorpyrifos, a widely used organophosphorus insecticide, was accomplished by using a white-rot fungal strain (Trametes hirsuta MTCC-1171). The experimental results showed that the fungal strain can effectively and rapidly degrade chlorpyrifos while using it as a sole source of carbon and energy when provided with mineral salt medium (MSM). The optimum experimental conditions for degradation of chlorpyrifos in liquid media can be summed as follows: initial pH 6.0; mycelial inoculum 0.18 ​± ​0.01 ​g ​L−1 (dry weight); chlorpyrifos concentration 150 ​mg ​L−1; pH 6.0; temperature 30 ​°C; and shaking speed 150 ​rpm. Under these optimal experimental parameters, T. hirsuta MTCC-1171 achieved ≥95% degradation of chlorpyrifos in 16 ​h of incubation. The degradation rate was quantified by employing HPLC followed by identification of degradation metabolites using gas chromatography–mass spectrometry (GC-MS). 2,4-Bis (1,1 dimethylethyl) phenol, a fuel additive, was found to be a major metabolite product of chlorpyrifos degradation. However, no metabolite bioaccumulation was observed in the process. Additionally, soil studies were carried out to investigate the degradation ability of the strain against chlorpyrifos, in a natural environment. During the assessment 37 ​± ​2.3% degradation was observed after 15 days of incubation. These results illustrate that T. hirsuta MTCC-1171 has a potential of using chlorpyrifos as a sole source of carbon. Besides, fundamental understanding gained through this work lays a foundation to investigate efficient and rapid bioremediation processes in agricultural and forest environments.

Chlorpyrifos degradation using binary fungal strains isolated from industrial waste soil

Chlorpyrifos degradation using binary fungal strains isolated from industrial waste soil

Highly efficient photocatalytic degradation of chlorpyrifos in aqueous solutions by nano hydroxyapatite modified CFGO/ZnO nanorod composite

A visible-light-driven photocatalyst, nanohydroxy apatite decorated carboxyl functionalized graphene oxide/zinc oxide nanorod (nHAP@CFGO/ZnR) composite was prepared and well characterized by FTIR, XRD, SEM/EDS, HRTEM, XPS, AFM, Raman, DRS, Surface area analyser, PL and EIS. nHAP@CFGO/ZnR composite exhibited high photoactivity and photostability to degrade the pesticide, chlorpyrifos (CP) in aqueous solutions under visible light. The band gap of the prepared photocatalyst was found to be 2.8 eV which is in the visible region. The maximum adsorption occurs at pH 3.5. The adsorption kinetic and isotherm data were described using pseudo-second-order kinetic model and Sips isotherm model, respectively. The photocatalytic degradation of CP was found to follow first-order kinetics and optimum pH for degradation was found to be 3.0. The regeneration and recyclability of the photocatalyst was examined upto five cycles that confirmed the relative stability of the photocatalyst.

Molecular Diversity of Chlorpyrifos Degrading Bacteria Isolated from Apple Orchard Soils of Himachal Pradesh

A total of seventy-two bacterial isolates were obtained employing enrichment culture technique from apple orchard soils contaminated with chlorpyrifos. Pure cultures of bacterial isolates were obtained using streak plate method on mineral salt medium. Bacterial isolates were characterized on the basis of morphology, culture and biochemical properties. Six bacterial isolates exhibited high extracellular organophosphorus hydrolase activity along with high tolerance towards high concentrations of chlorpyrifos. Genomic DNA extraction from bacterial isolates was done with phenol/chloroform method. Molecular Diversity of six chlorpyrifos degrading bacterial isolates was done employing RAPD-PCR technique by using 25 decamer primers, where amplification was showed by only 20 primers. A total of 337 amplified bands and 64 unique bands ranging in size from 100 to 4900bps were produced after RAPD analysis. The similarity coefficient estimated by Jaccard’s coefficient for these bacterial isolates was found to range between 31 to 64 percent.

Co-Al Layered double hydroxides decorated with CoFe2O4nanoparticles and g-C3N4nanosheets for efficient photocatalytic pesticide degradation

In this work, composite photocatalysts containing cobalt-aluminum layered double hydroxides (Co-Al LDH), graphitic carbon nitride (g-C3N4), and cobalt ferrite (CoFe 2O4) were prepared and applied for the photocatalytic degradation of chlorpyrifos (CP) as a model agricultural pollutant. The Co-Al LDH/g-C3N4-CoFe 2O4 composites showed enhanced photocatalytic activity compared to g-C3N4, due to the improved separation of photo-generated electrons and holes. 97.2% of CP was degraded during the photocatalytic process in the presence of the Co-Al LDH/g-C3N4-CoFe 2O4 photocatalyst. Almost complete degradation of CP was achieved under visible light irradiation, the photocatalytic activity of the composite was also dependent on the CP concentration, pH, and photocatalyst amount. A mathematical model incorporating these parameters was developed through response surface methodology, allowing optimized photodegradation of CP. The photo-oxidation of CP followed a pseudo-first-order kinetic model.

Magnetically retrievable cysteine modified graphene oxide@nickelferrite@titanium dioxide photocatalyst for the effective degradation of chlorpyrifos from aqueous solutions

A novel magnetically separable cysteine-modified graphene [email protected] ferrite @Titanium dioxide ([email protected]2O4@TiO2) composite was fabricated for the effective removal and subsequent photodegradation of the pesticide, chlorpyrifos (CP) from aqueous solutions. The composite material was characterized by DRS, FTIR, Surface Area Analyser, EDAX, SEM, TEM, PL, CV, VSM, EIS, XPS and XRD. The photocatalytic performance of [email protected]2O4@TiO2 composite was assessed by the degradation of CP under visible light irradiation. The bandgap of the photocatalyst was found to be 2.8 eV. The maximum adsorption occurs at pH 3.0. The photocatalytic degradation of CP was found to follow second-order kinetics and the optimum pH for degradation was found to be 7.0. The regeneration of the adsorbent and photocatalyst was also examined up to five cycles that confirmed the relative stability of the photocatalyst. The magnetic property of the photocatalyst was utilized, and it was separated from the solution by an external magnet. The recyclable and eco-friendly properties of the composite could be economically significant in the industry.

Rice recruits Sphingomonas strain HJY-rfp via root exudate regulation to increase chlorpyrifos tolerance and boost residual catabolism.

Inoculation with pollution-degrading endophytes boosts the catabolism of residual contaminants and promotes the pollution adaptation of host plants. We investigated the interaction pattern between Sphingomonas strain HJY-rfp, a chlorpyrifos-degrading endophytic bacterium, and rice (Oryza sativa) under pesticide stress using hydroponic cultivation. We observed a notable trend of endophytic root colonization in rice plants treated with 10 mg l-1 chlorpyrifos solution, and after 24 h the migration of HJY-rfp enhanced the chlorpyrifos degradation rate in leaves and stems by 53.36% and 40.81%, respectively. Critically, the rice root exudate profile (organic acids and amino acids) changed under chlorpyrifos stress, and variations in the contents of several components affected the chemotactic behaviour of HJY-rfp. HJY-rfp colonization dramatically activated defensive enzymes, which enabled efficient scavenging of reactive oxygen species, and led to 9.8%, 22.5%, and 41.9% increases in shoot length, fresh weight, and accumulation of total chlorophyll, respectively, in rice suffering from oxidative damage by chlorpyrifos. Endophytic colonization caused up-regulation of detoxification genes that have shown a significant positive correlation with chlorpyrifos degradation in vivo. Collectively, our results demonstrate that agrochemical stress causes plants to actively recruit specific symbiotic microbes to detoxify contaminants and survive better under pollution conditions.

Biodegradation of chlorpyrifos using isolates \xa0from contaminated agricultural soil, its kinetic studies

Extensive pesticides use is negatively disturbing the environment and humans. Pesticide bioremediation with eco-friendly techniques bears prime importance. This study evaluates the bioremediation of chlorpyrifos in soil using indigenous Bacillus cereus Ct3, isolated from cotton growing soils. Strains were identified through ribotyping (16s rRNA) by Macrogen (Macrogen Inc. Geumchen-gu, South Korea). Bacillus cereus Ct3 was resistant up to 125 mg L−1 of chlorpyrifos and successfully degraded 88% of chlorpyfifos in 8 days at pH 8. Bacillus cereus Ct3 tolerated about 30–40 °C of temperature, this is a good sign for in situ bioremediation. Green compost, farmyard manure and rice husk were tested, where ANOVA (P < 0.05) and Plackett–Burman design, results indicated that the farm yard manure has significant impact on degradation. It reduced the lag phase and brought maximum degradation up to 88%. Inoculum size is a statistically significant (P < 0.05) factor and below 106 (CFU g−1) show lag phase of 4–6 days. Michaelis–Menten model results were as follows; R2 = 0.9919, Vmax = 18.8, Ks = 121.4 and Vmax/Ks = 0.1546. GC–MS study revealed that chlorpyrifos first converted into diethylthiophosphoric acid and 3,5,6-trichloro-2-pyridinol (TCP). Later, TCP ring was broken and it was completely mineralized without any toxic byproduct. Plackett–Burman design was employed to investigate the effect of five factors. The correlation coefficient (R2) between experimental and predicted value is 0.94. Central composite design (CBD) was employed with design matrix of thirty one predicted and experimental values of chlorpyrifos degradation, having “lack of fit P value” of “0.00”. The regression coefficient obtained was R2 = 0.93 which indicate that the experimental vales and the predicted values are closely fitted. The most significant factors highlighted in CBD/ANOVA and surface response plots were chlorpyrifor concentration and inoculum size. Bacillus cereus Ct3 effectively degraded chlorpyrifos and can successfully be used for bioremediation of chlorpyrifos contaminated soils.

Efficiency of Pseudomonas putida in bioremediation of chlorpyrifos toxicity

At present, extensive varieties of pesticides are being used but the demand for Organophosphorus pesticide is increasing globally to control insects. Chlorpyrifos is a broad-spectrum, highly toxic, and chlorinated organophosphate insecticide that is synthetic in origin and is normally ester or thiol derivatives of phosphoric. The mode of action involves inhibiting acetyl-cholinesterase leading to the accumulation of acetylcholine causing neurotoxicity. Bacteria capable of degrading the pesticide, chlorpyrifos, were isolated from soil contaminatied with pesticiedes. In this way, three distinct chlorpyrifosdegrading strains of Pseudomonas putidia were isolated, and were characterized using morphological and biochemical analysis. Strain PB1 exhibited the greatest chlorpyrifos degradation rate reach to 100% and was consequently selected for further investigation. Degradation of chlorpyrifos by strain PC1 was rapid at 20 and 37C. Strain PB1 was able to effectively degrade chlorpyrifos in sterilized medium using high inoculum levels. The maximum degradation rate of chlorpyrifos was calculated as 0.08µg/ml to 0.002µg/ml during 6-12 days. Bacteria such as strain PB1, that use chlorpyrifos as a carbon source, could be employed for the bioremediation of sites contaminated with pesticides.

A Pesticide Biopurification System: A Source of Biosurfactant-Producing Bacteria with Environmental Biotechnology Applications

Biosurfactants, a wide group of compounds produced by different microorganisms, generally have less toxicity and are more biodegradable than synthetic surfactants. Biosurfactant-producing bacteria can be found in contaminated environments, such as soils receiving pesticide applications constantly, or in pesticides treatment systems where microorganisms are adapted to biodegrading pesticides. Five pesticide-tolerant bacteria previously isolated from a pesticide biopurification system were evaluated as biosurfactant-producers. Pseudomonas rhodesiae C4, Rhodococcus jialingiae C8 and Pseudomonas marginalis C9 strains were positive in qualitative tests. Biosurfactant production by these strains using Bushnell-Haas medium with olive oil at 2% (w/v) was evaluated as emulsification index, oil displacement, droplet collapse test and surface tension. After 144 h, these strains showed a similar emulsification index of &gt;55%. The two Pseudomonas (C4 and C9) strains showed lower superficial tension compared with Rhodococcus strain (C8)—34.47, 37.44 and 47.55 mN/m for strains C4, C9 and C8, respectively. The chemical characterization of the biosurfactants revealed the presence of glycolipids in P. rhodesiae (C4) and glycopeptides in P. marginalis (C9). The degradation of chlorpyrifos increased from 39.2% to 51.6% when biosurfactants produced by P.rhodesiae (C4) were added (10%) with respect to the control. Therefore, biopurification systems are a relevant source of biosurfactant-producing bacteria with environmental biotechnology applications.

Bio-synthesized Cu–ZnO hetro-nanostructure for catalytic degradation of organophosphate chlorpyrifos under solar illumination

In present study, a simple, effective and rapid green method using leaf extract of Melia azedarach was explored for the synthesis of Cu–ZnO nano heterojunction particles. The leaf extract of Melia azedarach acts as a reducing agent and prevents the agglomeration of nanoparticles. Different standard analytical techniques were used to study the morphology and size of synthesized nanocomposite. The efficiency of the synthesized material was tested as a photocatalyst for the degradation of simulated wastewater having chlorpyriphos pesticide. The different factors have been investigated such as pH of the solution, catalyst dosage and conact time. Approximately, 81% of chlorpyrifos was degraded after 240 min of solar illumination. The generation of hydroxyl radicals at the catalysts surface owing to photo-irradiation contributed to the chlorpyrifos degradation. The maximum photo-degradation (91%) of pesticides was observed at 6.0 pH. The pathway for the degradation of chlorpyriphos has been checked by LC-MS and this hinting the absence of any harmfull side product. The COD removal and TOC was found to be 32.4% and 28.5%, respectively. The photodegradation of chlorpyriphos using Cu–ZnO nanocomposite was followed the pseudo-first-order kinetic with higher value of regressiuon coefficient (0.99).

Optimization of biotic and abiotic factors liable for biodegradation of chlorpyrifos and their modeling using neural network approaches

Chlorpyrifos has a substantial risk to human health besides biodiversity. In the present study, a previously isolated bacterial strain Enterobacter sp. SWLC2 has been used to investigate its biodegradation potential in different soil-slurries systems and to optimize culture conditions to achieve enhanced biodegradation of chlorpyrifos. The optimization results indicate that the maximum (87%) spiked-chlorpyrifos biodegradation occurred in a sandy loam soil-slurry system in aeration mode after 18 days of incubation at the optimal temperature (35 °C) and pH (7). The effect of sources of carbon/nitrogen (organic sugars, organic acids, and amino acids, etc.) on the biodegradation of chlorpyrifos has been investigated and their optimal values are estimated. The neural networks have been designed to find the optimal values of earlier factors in the predictive modeling of degradation of chlorpyrifos.