Degradation Of Chlorpyrifos Research Articles

Mesoporous TiO2 @ Fe metal organic framework nanocomposite for an efficient chlorpyrifos detection and degradation

We report a sensitive voltammetric sensor for chlorpyrifos based on TiO2@Fe-imidazole MOF nanocomposite through hydrothermal process modified glassy carbon, screen printed carbon and graphene electrodes (MGCE, MSPCE & MSPGE). The electrode surface morphology and enhancement study was performed through SEM, electrochemical impedance spectroscopy Randels fit analysis and the results revealed that the TiO2@Fe-imidazole MOF modified electrodes reduced the resistance of the redox probe, which helps to promote the sensing ability and electro oxidation behaviour of chlorpyrifos. A voltammetric result revealed that the TiO2@Fe-imidazole MOF at MGCE, MSPCE and MSPGE detects potential at 8.91E−07:0.161 V, 2.52E−06; 0.26 V and 4.86E−06; 0.322 V respectively. The developed sensor exhibits low detection limit of 10 pg/drop through DROPSENS and revealed excellent degradation efficiency through spectroelectrochemical degradation of chlorpyrifos with TiO2@Fe-imidazole MOF. The real time drop sensing of TiO2@Fe-imidazole MOF at modified electrodes performed with real samples exhibits good sensitivity and selectivity towards chlorpyrifos. Hence, this characteristic of MOF helps to improve the futuristic environmental applications at one drop.

Green synthesis of rGO-AgNP composite using Curcubita maxima extract for enhanced photocatalytic degradation of the organophosphate pesticide chlorpyrifos.

In this study, Curcubita maxima leaves are used as a novel source for green synthesis of reduced graphene oxide - silver nanoparticle composite in a single pot. Characterization of the novel phyto source-driven composite was performed by UV-visible spectroscopy, Fourier transform infrared analysis, X-ray diffraction analysis, and field emission scanning electron microscopic methods. The assessment of degradation effect of chlorpyrifos by the synthesized nanocomposite was performed. The photocatalytic activity of the composite was demonstrated through two different processes as adsorption under room temperature and photocatalysis in the presence of sunlight. Different parameters such as pH, time, photocatalyst dose and pesticide concentration were optimized. The adsorption isotherms governing the photocatalytic adsorption process were investigated to predict the adsorption capacity of the synthesized nanocomposite. In addition, the results of antimicrobial activity of the nanocomposite against gram-positive, gram-negative bacteria and antifungal activity were also been found to be highly promising to utilize this composite for the removal of microbial contaminations in wastewater treatment.

Degradation insight of organophosphate pesticide chlorpyrifos through novel intermediate 2,6-dihydroxypyridine by Arthrobacter sp. HM01

Organophosphates (OPs) are hazardous pesticides, but an indispensable part of modern agriculture; collaterally contaminating agricultural soil and surrounding water. They have raised serious food safety and environmental toxicity that adversely affect the terrestrial and aquatic ecosystems and therefore, it become essential to develop a rapid bioremediation technique for restoring the pristine environment. A newly OPs degrading Arthrobacter sp. HM01 was isolated from pesticide-contaminated soil and identified by a ribotyping (16S rRNA) method. Genus Arthrobacter has not been previously reported in chlorpyrifos (CP) degradation, which shows 99% CP (100 mg L−1) degradation within 10 h in mMSM medium and also shows tolerance to a high concentration (1000 mg L−1) of CP. HM01 utilized a broad range of OPs pesticides and other aromatic pollutants including intermediates of CP degradation as sole carbon sources. The maximum CP degradation was obtained at pH 7 and 32 °C. During the degradation, a newly identified intermediate 2,6-dihydroxypyridine was detected through TLC/HPLC/LCMS analysis and a putative pathway was proposed for its degradation. The study also revealed that the organophosphate hydrolase (opdH) gene was responsible for CP degradation, and the opdH-enzyme was located intracellularly. The opdH enzyme was characterized from cell free extract for its optimum pH and temperature requirement, which was 7.0 and 50 °C, respectively. Thus, the results revealed the true potential of HM01 for OPs-bioremediation. Moreover, the strain HM01 showed the fastest rate of CP degradation, among the reported Arthrobacter sp.Graphical

Molecular characterization of chlorpyrifos degrading bacteria isolated from contaminated dairy farm soils in Nakuru County, Kenya

Chlorpyrifos (CP) is an organophosphate widely used as an insecticide and acaricide. Extensive application of CP contaminates ecosystems, polluting the environment and food products, creating health complications to humans due to its neurotoxicity. The study evaluated CP bioremediation by bacteria isolated from dairy farm soils in Nakuru County, Kenya, through enrichment culture technique. The growth response of the bacteria and degradation of chlorpyrifos was monitored every five days using UV-VIS Spectrophotometer (600nm). Enrichment culture technique led to the isolation of eighteen (MA1-MA18) potential CP degraders belonging to the genera Pseudomonas, Stenotrophomonas, Bacillus, Alicaligenes, and Achromobacter. The efficacy of four (4) strains was further investigated using Gas Chromatography-Mass Spectrometry (GC-MS) analysis. The results showed that all four strains significantly degraded chlorpyrifos in Minimum Salt Medium (MSM): Lysinibacillus sp.HBUM206408 (87.16 %), Stenotrophomonas maltophilia (82.04 %), Pseudomonas putida (89.52 %), and Achromobacter insuavis (91.08 %) within 16 days, producing 2-Hydroxy-3, 5, 6-trichloropyridine (TCP) as the main metabolite. Therefore, these strains can be used to degrade chlorpyrifos in contaminated soil. There is a need for further studies to determine the possible mechanisms and other metabolites of chlorpyrifos degradation by the isolates obtained in the study. Besides, future studies should explore the efficacy and survival of the organisms in the contaminated environment.

An integrated hybrid nanoplatform with polymer coating: Zinc based green nanocomposites with improved photoactivity under sunlight irradiation

Domestic, farming, and industries required many highly persisting and low-priced pesticides. Environmental concern arose via bioaccumulation and toxicity of pesticides emphasizing for requirement of effective removal techniques based on novel nanomaterials. To substantiate this, the potential of crystalline hybrid nanocomposites of zinc oxide and zinc sulfide with urea-formaldehyde (ZnO@UF and ZnS@UF) were utilized to remove hazardous pesticides. ZnO@UF and ZnS@UF were synthesized via green methodology using Sapindus mukorossi seed extract as natural surfactant. Characterization indicated the successful formation of hybrid nanoparticles (particle size: <100 nm) with polymer coating. Zinc oxide/sulfide-resin (25 mg) proved to be highly efficient in the degradation of chlorpyrifos (89–92%) at optimum pollutant concentration (2 mg L−1) and under neutral pH conditions. The sharp decline in chlorpyrifos concentration followed by slow reduction revealed first-order kinetics initiated with Langmuir adsorption. The highest removal by hybrid nanocomposites showed their superiority attributed to enhanced surface area and narrow band gap of ZnO@UF (78.9 m2g−1; 1.3 eV) and ZnS@UF (63.8 m2g−1; 1.8 eV) as an effect of semiconducting and interactive feature. Moreover, ZnO@UF reduced the half-life of chlorpyrifos up to 3.4 h than ZnS@UF (3.5 h) and bared ZnO (4.9 h) and ZnS (6.1 h). Scavenger analysis by ethanol, benzoquinone, and triethanolamine confirms presence of hydroxyl radicals, holes, and O2.⁻, responsible for degradation of chlorpyrifos. GC-MS analysis revealed degradation of chlorpyrifos into safer and smaller bi-products. Conclusively, by virtues of high surface activity, high reusability (n = 10), stability, and greater charge separation, hybrid ZnO@UF and ZnS@UF nanocomposite may prove as an alternative catalyst for industrial application with intense scope.

Degradation mechanism and toxicity assessment of chlorpyrifos in milk by combined ultrasound and ultraviolet treatment

The aim of this study was to compare the degradation kinetics of chlorpyrifos by treatment with ultrasound (US), ultraviolet radiation (UV) and a combination of both (US/UV), to evaluate the toxicity of the degradation products and the effect of the treatments on milk quality. US/UV markedly accelerated the degradation of chlorpyrifos. The half-life of chlorpyrifos by US/UV was 6.4 min, which was greatly shortened compared to the treatment with US or UV alone. Five degradation products were identified by GC–MS, and a degradation pathway for chlorpyrifos was proposed, based on density functional theory calculations. According to the luminescent bacteria test and predictions from a structure/activity relationship model, the toxicity of the degradation products was lower than that of chlorpyrifos. In addition, US/UV treatment had little effect on the quality of the treated milk. Therefore, US/UV can be used as a potential non-thermal processing method to degrade pesticide residues in milk.

Field test of the TOXSWA pesticide fate model: Comparison of simulated and observed chlorpyrifos in water, sediment and macrophytes in four stagnant ditches

TOXSWA is a numerical model describing pesticide behavior in an edge-of-field waterbody. It is widely used to predict exposure in regulatory risk assessment for aquatic ecosystems. Exposure concentrations are predicted based upon pesticide process parameters obtained in standardized laboratory experiments. However, few tests of the model performance based on field data have been carried out. We compare simulated concentrations to observations from a field experiment with four shallow stagnant ditches over sprayed with chlorpyrifos, a moderately volatile pesticide with a significant sorption capacity. Input parameters describing the four ditches, such as dimensions, water depth, sediment and macrophyte characteristics were measured in detail. Additionally, laboratory experiments were carried out to determine site-specific values for parameters describing chlorpyrifos degradation in water and sediment, as well as sorption to the two dominant macrophyte species. Based upon these estimated parameters, the correspondence between simulated and measured concentrations in water, sediment and macrophytes is poor. We attribute this discrepancy to a lack of site-specific input for the processes of volatilization and sorption to sediment, which both are important processes for chlorpyrifos. Therefore, we calibrated TOXSWA using the optimization tool PEST. The transfer coefficient for volatilization and the coefficient for sorption to sediment were optimized based on the observed concentrations in water and sediment. This resulted in a substantial improvement of correspondence. Optimized values of the transfer coefficient for volatilization and the coefficient for sorption to sediment are substantially higher than their initial estimates (4–8-fold and 2–4-fold increase, respectively), but can be well explained. The optimized coefficients vary less than a factor 2 between the four ditches. We conclude that TOXSWA can adequately predict chlorpyrifos behavior in the four ditches, provided that reliable site-specific parameter estimates are available. Field tests for other pesticides, waterbodies and agro-environmental conditions are warranted.

Effective biocatalyst developed via genipin mediated acetylcholinesterase immobilization on rice straw derived cellulose nanofibers for detection and bioremediation of organophosphorus pesticide

This study aims to utilize cellulose nanofibers (CNFs) derived from rice straw to immobilize acetylcholinesterase (AChE) and their effective use as fluorescent sensor cum biocatalyst for sensing and degradation of chlorpyrifos (CPF) into 3,5,6-trichloro-2-pyridinol (TCP) and benign metabolites. AChE immobilized CNFs (AChE@CFs) exhibited excellent selectivity towards CPF in presence of other pesticides, amino acids and heavy metal ions with limit of detection as 90 nM. As compared to free enzyme, a better storage stability, higher endurance to change in pH and temperature and recyclability upto 20 cycles with 8% loss of activity was achieved. AChE@CFs effectively degraded CPF in 36 h. Kinetics of degradation revealed first order kinetics with rate constant of 0.0611 h−1 and half-life of 11.34 h, better than the reported studies leading to conclusion that AChE@CFs is efficacious catalyst for degradation of CPF, not reported hitherto.

Enterobacter sp. SWLC2 for biodegradation of chlorpyrifos in the aqueous medium: Modeling of the process using artificial neural network approaches

Chlorpyrifos is a widely used organochlorine pesticide. The unsystematic use of pesticides for the restrain of soil-borne pests and bacterium causes pollution of ecosystems and harming the health of animals and humans. Moreover, due to high persistence, mobility, and higher toxicity in soil environments, it causes severe destruction of species. Therefore the investigation of the degradation process of chlorpyrifos polluted locations to diminish its lethal effect is important. With this objective, the present study reports the efficiency of new isolated bacterial strain SWLC2 for chlorpyrifos degradation in an aqueous medium and the biotic/abiotic factors influencing the process and their optimization using statistical Taguchi design and artificial neural network (ANN) approaches. Results revealed a higher efficiency of bacterium SWLC2 for chlorpyrifos degradation at optimal environmental and general conditions (800 μL inoculum, glucose (97%), arginine (89%), and succinic acid (83%)). External supplements (carbon and nitrogen sources) had stimulating effects on chlorpyrifos biodegradation depending on the concentration of supplemented substrate. Chlorpyrifos biodegradation by SWLC2 also varied as the initial concentration of the tested compound changes, following first-order kinetics. The finding provides a basic understanding of the application of the bacteria strain SWLC2 in the bioremediation of soils contaminated with chlorpyrifos pesticide. ANN approaches have achieved an average R2 equal to 0.98–0.99 in the prediction of chlorpyrifos degradation considering the affecting biotic/abiotic factors.

Environmental Distribution, Metabolic Fate, and Degradation Mechanism of Chlorpyrifos: Recent and Future Perspectives.

Pesticides play a significant role in crop production and have become an inevitable part of the modern environment due to their extensive distribution throughout the soil ecosystem. Prophylactic applications of chlorpyrifos (CP) affect soil fertility, modify soil microbial community structure, and pose potential health risks to the nontarget organisms. Bioremediation through microbial metabolism is found to be an ecofriendly and cheaper process for CP removal from the environment. So far, various bacterial and fungal communities have been reported for CP and its metabolites degradation. Organophosphorus hydrolase (OPH) and methyl parathion hydrolase (MPH) are crucial bacterial enzymes for CP degradation as they efficiently hydrolyze the unbreakable P-O and P = S bond. This review discusses the prospects of toxicity level, persistency, and harmful effects of CP on the environment. CP degradation mechanisms, metabolic pathways, and key enzymes, along with their structural details, are also featured. The highlights on molecular docking with OPH and MPH enzyme for CP show the best binding affinity with OPH; hence, it is an essential part of CP degradation. Simultaneously, metagenomic analysis of soil from contaminated agricultural lands and wastewater was analyzed with the goal to identify the dominant CP degraders and enzymes. The identification of potent degraders, key enzymes, and evaluation of microbial community dynamics upon pesticide exposure can be used as a warning for its dissemination and biomagnification into the food chain.

Microbial degradation of chlorpyrifos and carbosulfan in sterile soil under laboratory conditions

Bacterial degradation of chlorpyrifos and carbosulfan in sterile soil under laboratory condition has been investigated at different concentrations (100, 200 and 300 μg g–1 of soil for chlorpyrifos and 100 and 400 μg g–1 of soil for carbosulfan). HPLC data of chlorpyrifos after 60 days of sampling revealed that the insecticide has degraded to 98.48, 98.22 and 95.19 per cent from its initial concentrations of 100, 200 and 300 μg g−1 in sterile soil. Whereas, the degradation percentages were 29.58, 37.16 and 28.40 after 60 days from the control samples without microbial consortium. Similarly, 100 per cent degradation for carbosulfan in sterile soil by microbial consortium was achieved at 30 days after treatment for 100 μg g−1 and at 60 days for 400 μg g−1 compared to control. Faster degradation by bacterial consortium was recorded for both the insecticides which followed pseudo first order rate kinetics. The study confirmed that microbial consortium could effectively be utilized for faster bioremediation of these insecticides in sterile soil under laboratory conditions. This consortium can also be used for effective biodegradation of two insecticides in mango orchard soil under field conditions.

Polyamidoamine Dendrimers-MoS2 Nanocomposites for Photocatalytic Degradation of Chlorpyrifos and Glyphosate Pesticides

Polyamidoamine dendrimers-MoS2 nanocomposites for photocatalytic degradation of chlorpyrifos and glyphosate pesticidesPolyamidoamine dendrimer functionalized with MoS2 nanoparticles was synthesized and fully characterized using field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, X-ray diffractometry, Brunauer-Emmett-Teller, and thermal gravimetric analysis. The synthesized nanocomposite showed excellent photocatalytic activities for the degradation of two commonly used pesticides (chlorpyrifos and glyphosate). According to the optimization study, the pH value of 10 and the minimum reaction time of 110 minutes is required for optimal degradation of pesticides. Based on the kinetics study on the photocatalytic reaction, it was inferred that more than 95% of the pesticides were degraded into non-harmful products in less than two hours. By comparing the obtained data in this study with previous reports for photocatalytic degradation of chlorpyrifos and glyphosate, it was concluded that the present nanocomposite was able to degrade pesticides faster and more efficient.Keywords: Chlorpyrifos, Glyphosate, Polyamidoamine dendrimer, Photocatalyst, Pesticide

Comparison of Mw/Pds System and Mw/Pms System for Degradation of Chlorpyrifos in Soil: Mechanism and Products

Comparison of Mw/Pds System and Mw/Pms System for Degradation of Chlorpyrifos in Soil: Mechanism and Products

Gold Nanoclusters@Zif-8 Fluorescent Probe for Ratiometric Monitoring of Chlorpyrifos Degradation with High Anti-Interference Ability

Gold Nanoclusters@Zif-8 Fluorescent Probe for Ratiometric Monitoring of Chlorpyrifos Degradation with High Anti-Interference Ability

Biocatalytic degradation of organophosphate pesticide from the wastewater and hydrolytic enzyme properties of consortium isolated from the pesticide contaminated water

The indiscriminate application of various pesticides leads to toxicity to the humans, animals, fishes and threatens the environment and ecosystem. The present study was aimed to investigate pesticide degrading bacteria from the pesticide contaminated sample and to localize organophophate hydrolase activity from the bacteria. Sediment sample was selected as the source of microorganism for the degradation of chlorpyrifos. Enterobacter aerogenes CP2 and Streptococcus pyogenes CP11 isolated from the contaminated sample removed 77 ± 1.8%, 74.2 ± 3.1 chlorpyrifos. These strains have the potential to utilize pesticide as the source of carbon and energy. The pesticides inoculated with both CP 2 and CP 11 enhanced biodegradation of chlorpyrifos at optimized condition. E. aerogenes CP2 and S. pyogenes CP11 produced organophosphate hydrolase activity and localized enzyme biosynthesis. Organophosphate hydrolase activity was high in intracellular, followed by outer membrane and extracellular sample for both bacteria. The treated wastewater has no impact on the seed germination indicated normal cell division, cell elongation and indole-3 acetic acid synthesis. The strain CP2 has the rapid rate of organophosphate degradation among Enterobacter species.

IMPACT OF CHLORPYRIFOS ON BACILLUS CEREUS OP3 SOIL BACTERIA ISOLATED FROM RHIZOSPHERE

Chlorpyrifos is a pesticide belongs to organophosphate group and widely used in Indian agriculture. The evaluation of chlorpyrifos removal from the soil using pesticide degrading bacteria will help in the resilience of soil fertility. Bacteria capable of degrading chlorpyrifos were isolated from chlorpyrifos-treated agricultural soil. The degradation of chlorpyrifos by a potential isolate was determined using FTIR and quantified using the molecular extinction coefficient in an ELISA reader. GC-MS was used to analyze the chlorpyrifos degradation metabolites. Additionally, the effect of chlorpyrifos exposure on genomic DNA and total protein content was determined. A total of 174 bacterial colonies were isolated, of which only 40 bacterial colonies were pesticide tolerant in 100ppm chlorpyrifos. Among them, only three isolates (OP3, OP5, and OP7) demonstrated tolerance above 100ppm. Within five days of incubation, OP3 demonstrated tolerance to chlorpyrifos concentrations up to 300ppm and 47 percent of chlorpyrifos was removed. By 16S rRNA sequencing, potential OP3 isolates were identified as Bacillus cereus OP3. FTIR spectra confirmed that B. cereus degraded chlorpyrifos, with 92.4 percent of chlorpyrifos degraded. In GC-MS analysis, metabolites such as MNitroaniline and 4-Methyl-2-{(4-Nitrophenyl)Thio}Pyrimidine were detected. Chlorpyrifos overexposure alters the total protein content of exposed cells and induces DNA breaks. As a result, it is concluded that B. cereus is able to degrade chlorpyrifos and the excessive use of pesticides make some changes in the soil bacteria. Overexposure of chlorpyrifos leads to an increase in total protein content and induce DNA strands breaks in pesticide degrading Bacillus cereus.

Alleviation of Chlorpyrifos Toxicity in Maize (Zea mays L.) by Reducing Its Uptake and Oxidative Stress in Response to Soil-Applied Compost and Biochar Amendments.

Chlorpyrifos (CP) is a pesticide used extensively in agricultural crops. Residual CP has been found in a variety of soils, vegetables and fruits indicating a serious danger to humans. Therefore, it is necessary to restrict its entry into agricultural products for food safety. A wire-house pot experiment was conducted with maize plants in biochar- and compost-amended soil (at 0.25% and 0.50%, respectively, in weight-by-weight composition) contaminated with 100 and 200 mg kg−1 of CP, respectively. Results indicated toxicity at both CP levels (with 84% growth reduction) at CP 200 mg kg−1. However, application of compost and biochar at the 0.50% level improved the fresh weight (2.8- and 4-fold, respectively). Stimulated superoxide dismutase (SOD) and peroxidase (POX) activities and depressed catalase (CAT) activity were recorded in response to CP contamination and were significantly recovered by the amendments. Both amendments significantly decreased the CP phytoavailability. With biochar, 91% and 76% reduction in the CP concentration in maize shoots and with compost 72% and 68% reduction was recorded, at a 0.50% level in 100 and 200 mg kg−1 contaminated treatments respectively. Compost accelerated the CP degradation in postharvest soil. Therefore, biochar and compost amendments can effectively be used to decrease CP entry in agricultural produce by reducing its phytoavailability.

Chlorpyrifos degradation, biocontrol potential and antioxidant defence activation under pesticide stress by rhizosphere bacteria isolated from rhizosphere of peach (Prunus persica) plants

ABSTRACT Current experiments were done to isolate plant growth-promoting rhizobacteria (PGPR) from peach (Prunus persica) rhizosphere having biocontrol, biodegradation and defence mechanism activation against pesticide toxicity. PGPR strains (Pseudomonas and Bacillus) showed biocontrol activity against phytopathogens. Bacillus flexus PS-26 tolerated a maximum amount of chlorpyrifos and was also able to degrade different concentrations of chlorpyrifos within 30 h. Bacillus flexus PS-26 formed more biofilm, released a high amount of antioxidants and exopolysaccharides under chlorpyrifos stress, which suggested its detoxification role. The present study proved Bacillus flexus PS-26 to be a super-bioinoculant, which could protect plants against pesticide.

Chitosan functionalized Halloysite Nanotubes as a receptive surface for laccase and copper to perform degradation of chlorpyrifos in aqueous environment

Chitosan (CTS) functionalized Halloysite Nanotubes (HNT) have been used as receptive nano-supports for the grafting of copper (Cu) and laccase (Lac) for the degradation of chlorpyrifos. The developed nanocomposite Lac@Cu-CTS-HNT showed 83.4% Lac immobilization which was further characterized by TEM, SEM-EDX, FTIR, XRD, DSC and TGA. The chlorpyrifos degradation studies were performed under constant stirring for 24 h with both free enzyme and Lac@Cu-CTS-HNT and were analysed through HPLC. Percentage degradation of chlorpyrifos with the nanocomposite went as high as 97% for 50 μg/mL chlorpyrifos at neutral pH and room temperature. Variable pesticide and nanocomposite concentration, pH, and temperature studies for pesticide degradation were also performed, followed by reusability studies. The nanocomposite maintained its degradation ability at ~97% even at variable temperature and pH conditions. Reusability study was performed 5 times wherein the degradation percentage remained the same after 5 cycles (~<95%). Degradation kinetics were also performed for the nanocomposite in the presence and absence of the immobilized enzyme. Through this study, it is suggested that Lac@Cu-CTS-HNT can be a potential nano-catalyst for the degradation of chlorpyrifos in aqueous environment.

Dissipation of Chlorpyrifos in Bottled Tea Beverages and the Effects of (−)-Epigallocatechin-3-Gallate

Bottled tea beverages (BTB) are popular for the health benefits and convenience. Because chlorpyrifos (CP) is commonly used as a biomarker for exposure, as well as a pesticide in the field, it is important to determine the dynamics of CP dissipation in BTB to better perform risk assessments. This study focused on the dynamic behavior of CP for 22 days by fortifying bottled green tea, dark tea, and oolong tea beverages with the parent chemical and analyzing the degradation products. Photoinduction was used to generate the two transient intermediates: the reactive oxygen species from H2O2 and the triplet excited state of CP from the parent chemical in water were designed to observe the effects of (-)-epigallocatechin-3-gallate (EGCG) on the dissipation and transformation of CP. The results indicated that the CP degraded in BTB and the main products were detected. The half-life values of CP illustrated that EGCG increased the dissipation of CP by combination with CP and inhibited the generation of CP-oxon by scavenging the emerged oxidant, the reactive oxygen species, and interfering with the transformation of the triplet excited state of CP. This work suggests EGCG could play various roles in the dissipation and transformation of CP. Thus, a comprehensive identification of CP degradation should be performed when assessing the exposure risk in drinking BTB.