Dimethoate Residues Research Articles

Synergistic Effect of Copper oxide Nanoparticles and Diazonium-Modified Carbon Nanotubes for Colorimetric Detection of Dimethoate Residues in Food Products

Synergistic Effect of Copper oxide Nanoparticles and Diazonium-Modified Carbon Nanotubes for Colorimetric Detection of Dimethoate Residues in Food Products

Synthesis of a new camphor-derived carboxylesterase-activated fluorescent probe for sensitive detection of dimethoate residues in agricultural products and its applications in biological systems

In this paper, a camphor-derived enzyme activatable probe CPA was synthesized for detecting dimethoate pesticide. The ester bond of probe CPA could be selectively hydrolyzed and fragmented in the presence of carboxylesterase (CE), which caused a remarkably enhanced green fluorescence signal at 501 nm. Probe CPA could function as an effective fluorescent platform for the sequential detection of dimethoate due to the obvious inhibition effect of dimethoate on the activity of CE. The detection limit of probe CPA to dimethoate was computed to be 0.1104 μg/mL. Even more important, CPA was effectively utilized for quantitative determination of trace dimethoate residues in agricultural products including fresh vegetables and fruits with good accuracy. Furthermore, the probe CPA could realize the detection of dimethoate in living cells and zebrafish. This work is expected to provide a highly sensitive and accurate analytical method for detecting organophosphorus pesticide residues in food samples and biological systems.

Colorimetric sensor and visual enzyme sheets for sensitive detection of dimethoate residue in vegetables based on laccase-like activity of coral-like silver citrate

The overutilization of dimethoate may lead to its deposition in both the environment and crops, which potentially induces neurological, respiratory, and hepatic abnormalities upon absorption by organisms. Colorimetry can accurately determine dimethoate, but there are still many challenges in the rapid, convenient, and point-of-care detection. Herein, based on the inhibitory effect of dimethoate on the laccase activity of silver citrate (AgCit), a smartphone-assisted colorimetric sensor and rapid detection enzyme sheets were constructed. It was demonstrated that dimethoate could adsorb on the surface of AgCit and inhibit the production of semiquinone radicals in the reaction system. Then, the AgCit laccase activity was inhibited, causing the colorimetry sensor and the enzyme sheets turned light red or even colorless. The constructed sensor has higher sensitivity and the limit of detection for dimethoate is 1.0 μg⋅L−1. Moreover, the developed enzyme sheets have good selectivity and specificity, and display the detection results within 5 min. Thus, the colorimetric sensor and the constructed enzyme sheets are expected to be used for large-scale preliminary detection of dimethoate residues in actual agricultural products.

Probabilistic risk assessment of endocrine disrupting pesticides in Iran

ABSTRACT The chronic dietary risk assessment for 34 pesticides suspected of acting as endocrine disrupters in Iran was assessed by comparing TMDI with the Acceptable Daily Intakes (ADI). Of 34 investigated endocrine-disrupting pesticides (EDPs), 6 had TMDI > ADI. In addition, potential non-carcinogenic and carcinogenic health risk assessments were evaluated using Monte Carlo simulation. HQ in wheat was 17.40 and 20.29 in adults and children, respectively. Due to dimethoate residue in wheat, HQ was 2.78, and for fenitrothion residue, 3.22. HI was 21.22 for adults and 24.76 for children in wheat, more than 1. Total Carcinogenic risk (TCR) due to EDPs residues was 6.40 × 10−5 in apples, in citrus fruits 5.97 × 10−5, 3.33 × 10−5 in cucumber, 5.30 × 10−5 in lettuce, in potato was 2.36 × 10−5, in rice was 1.61 × 10−5, 1.78 × 10−5 in tomato, and due to epoxiconazole residues in wheat was 3.18 × 10−5, more than acceptable limit 1.0 × 10−6. Therefore, consumers were at significant risk of carcinogenesis. Abbreviations: PCBs: polychlorinated biphenyls; BPA: Bisphenol A; ED: Endocrine Disrupting; EDCs: Endocrine Disrupting Chemicals; EDPs: Endocrine Disrupting Pesticides; ADI: Acceptable Daily Intake; TMDI: Theoretical Maximum Daily Intake; FAO: Food and Agriculture Organization; WHO: World Health Organization; MRL: Maximum Residue Limit; HQ: Hazard Quotient; HI: Hazard Index; CR: Cancer Risk; TCR: Total Cancer Risk; PPP: plant protection products

Development and validation of a modified QuEChERS method coupled with LC-MS/MS for simultaneous determination of difenoconazole, dimethoate, pymetrozine, and chlorantraniliprole in brinjal collected from fields and markets places to assess human health risk

An effective and sensitive analytical method was developed to quantify the most common pesticide residues (difenoconazole, dimethoate, pymetrozine, and chlorantraniliprole) used for brinjal cultivation in Bangladesh. The quantification of the analytes was done using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The samples were extracted using a modified QuEChERS method and followed by purification with dispersive solid phase extraction (d-SPE) sorbents (PSA, GCB, and C18). Matrix-matched calibration with a regression coefficient R2 ≥ 0.9964 were used to minimize the brinjal matrix effect. The method was validated in quintuple (n = 5) at five different spiked levels (8–400 μg/kg) having recoveries in the range of 70.3–113.2% with relative standard deviations RSDs ≤6.8%, limits of detection (LOD) and limits of quantification (LOQ) was in the range of 0.15–0.66 μg/kg and 0.4–2.0 μg/kg, respectively, for the four analytes. A total 100 samples (50 samples directly from fields of Jessore district, Bangladesh and 50 samples from local market of Dhaka, Bangladesh) were collected to analyse the pesticides residue. The result showed that pesticides residue was found in both the field and market collected samples, 54% and 38%, respectively. The overall mean residue levels of four pesticides in field samples were significantly higher than those of market samples. Moreover, 20% of the field samples and 10% of the market samples had dimethoate residues, which were the most abundant among the four analytes and it ranged from 0.017 to 0.252 mg/kg. In terms of health risk assessments, dimethoate showed the highest estimated daily intake (EDI) and hazard quotient (HQ) values that are 3.02 × 10−5 mg/kg/day and 1.51%, respectively, in field samples. Till now, there have been no regulations or guidelines for the maximum admissible pesticide residue in Bangladesh. Therefore, the above findings will be an initial step for the regulatory authorities of Bangladesh to implement regulations and guidelines for pesticide usage.

Toxicity of Insecticides in the Adult and Larva Olive Fruit Fly, after Estimation of the Dislodgeable Foliar and Fruit Residues in Olive Trees by LC-MS/MS and GC-MS/MS

“Can systemic insecticides be used in bait spots in order to kill the adult olive fly?” Effort was directed toward providing an answer to that question. Both field and laboratory tests were implemented to detect the dislodgeable residues of dimethoate, phosmet and b-cyfluthrin in olive leaves and fruit using the LC-MS/MS and GC-MS/MS chromatographic techniques. Residues of dimethoate declined more over time than those of phosmet, while levels of beta-cyfluthrin remained almost stable, both in leaves and fruit. Additionally, significantly higher and faster toxicity of dimethoate and beta-cyfluthrin (>92%) compared to phosmet (80%) to fly adults was shown, which was reduced significantly after a two-week period. Conversely, 100% mortality of the larval stages within olive flesh was observed at the 2nd day for dimethoate and at the 7th day for phosmet. Although phosmet was not expected to contribute to preventing larval development, its application in bait sprays presented similar toxicity to that of dimethoate. However, no larval toxicity was recorded in beta-cyfluthrin. As a primary conclusion, we recommend the avoidance of the use of systemic insecticides in bait sprays.

Human health risk assessment of pesticides in lettuce and spinach grown in urban backyard garden soils

Pesticide residues in lettuce and spinach could be a serious human health concern since the average per capita consumption per day of leafy salad vegetables is ∼60 g. Here, we determined the leftover residues (LoR) of dimethoate, 2,4-D, glyphosate, and chlorothalonil in lettuce and spinach grown in three urban backyard soils to assess their potential human health hazards. Pesticide residues were extracted by QuEChERS method and quantified through LC-MS and LC-DAD. In most cases, residue levels in the vegetable samples were above the EU-MRLs. Soil organic carbon, silt, oxides of iron and aluminium negatively correlated (P < 0.05) with LoR of the pesticides while LoR positively correlated (P < 0.05) with contents of sand and clay, and pH. The estimated short-term intake (ESTI) values (mg kg1 day1) for dimethoate, 2,4-D, glyphosate and chlorothalonil even at recommended doses in case of lettuce and spinach were 0.003–9.90 × 103 and 0.005–37.10 × 103 for adults and children, respectively, whereas the corresponding estimated daily intake (EDI) values were 0.007–9.58 × 103 and 0.03–35.90 × 103. Accordingly, the calculated values of non-cancer acute health hazard (aHI <100%) and hazard quotient (HQ <1) indicated that consumption of salad vegetables grown in soils spiked with pesticides at doses recommended in agriculture does not pose human health risks. On the other hand, both lettuce and spinach grown in soils at ten-fold higher concentrations of dimethoate or chlorothalonil exceeded the threshold limit of aHI (>100%) for children and HQ > 1 for both children and adults, suggesting their potential acute and chronic health hazards. The present study, for the first time, provides health awareness about the consumption of pesticide-contaminated leafy vegetables grown in urban backyard garden soils.

Detection of Pesticide Residues in Olive Leaves From İzmir, Turkey

Turkey, especially the Aegean region, has very suitable lands for olive cultivation. In this work, the olive leaves extracts were treated with pesticide solution and also Bordeaux mixture. Olive varieties in their natural environment were collected after 1 year, and the amount of pesticides they contained was measured. As a result of the QuEChERS method using LC-MS/MS and GC-MS/MS techniques, no pesticide residues were detected in any samples. The pesticide residues determined in the samples used in this study do not exceed the maximum limits specified in the Turkish Food Codex and the European Commission. There are no quantifiable residues of abamectin, acetamiprid, azoxystrobin, difenoconazole, diflubenzuron, diflufenican, dimethoate, dodine, emamectin benzoate, indoxacarb, lufenuron, malathion, novaluron, phosmet, pyriproxyfen, spinosad, thiacloprid, and triflumuron were detected in any olive samples by using LC-MS/MS method. Also, alpha-cypermethrin, beta-cyfluthrin, cyflutrin, deltamethrin, and lambda-cyhalothrin were not detected in samples by GC-MS/MS method. Accordingly, they agree with the results found. The results obtained showed that the pesticide solution used protected the olives from pests and did not have a harmful effect on the olives.

Analysis of pesticide residues in vegetables purchased from local markets of Mymensingh district of Bangladesh based on QuEChERS Extraction and Gas Chromatography

The study was conducted to analyze organophosphorus pesticide residues in two common vegetables (cauliflower and eggplant) collected from five local markets of Mymensingh district of Bangladesh. The collected samples were carried to the Pesticide Analytical Laboratory, Entomology Division of Bangladesh Agricultural Research Institute (BARI), Gazipur on the same sampling day. The collected samples were analyzed using Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) extraction technique and Gas Chromatography (GC) coupled with Flame Thermionic Detector (FTD). In total, 60 vegetable samples were analyzed in this study. Out of 30 analyzed samples of cauliflower, 5 samples (17% of the total number of samples) contained residues of dimethoate, chlorpyrifos and quinalphos, where 3 samples contained residues above the maximum residue limits (MRLs). Among the 30 analyzed samples of eggplant, 5 samples (17% of the total number of samples) contained residues of chlorpyrifos, quinalphos, and dimethoate, where only one sample contained residues above MRL. This study reflects the actual scenario of pesticide residues remain in cauliflower and eggplant collected from local markets of Mymensingh district, which will help the consumer to be aware of their health and safety. Thus, continuous monitoring of pesticide residues in vegetables should be strengthened. Asian Australas. J. Food Saf. Secur. 2022, 6 (1), 10-17

Dimethoate residues in Pakistan and mitigation strategies through microbial degradation: a review.

Organophosphate pesticides (OPs) are used extensively for crop protection worldwide due to their high water solubility and relatively low persistence in the environment compared to other pesticides, such as organochlorines. Dimethoate is a broad-spectrum insecticide that belongs to the thio-organophosphate group of OPs. It is applied to cash crops, animal farms, and houses. It has been used in Pakistan since the 1960s, either alone or in a mixture with other OPs or pyrethroids. However, the uncontrolled use of this pesticide has resulted in residual accumulation in water, soil, and tissues of plants via the food chain, causing toxic effects. This review article has compiled and analyzed data reported in the literature between 1998 and 2021 regarding dimethoate residues and their microbial bioremediation. Different microorganisms such as bacteria, fungi, and algae have shown potential for bioremediation. However, an extensive role of bacteria has been observed compared to other microorganisms. Twenty bacterial, three fungal, and one algal genus with potential for the remediation of dimethoate have been assessed. Active bacterial biodegraders belong to four classes (i) alpha-proteobacteria, (ii) gamma-proteobacteria, (iii) beta-proteobacteria, and (iv) actinobacteria and flavobacteria. Microorganisms, especially bacterial species, are a sustainable technology for dimethoate bioremediation from environmental samples. Yet, new microbial species or consortia should be explored.

A novel colorimetric strategy for rapid detection of dimethoate residue in vegetables based on enhancing oxidase-mimicking catalytic activity of cube-shape Ag2O particles

Although many colorimetric methods have been established for pesticide analysis, most of them rely on inhibiting catalytic activities of natural enzymes or nanozyme, easily leading to false positives in results of pesticide detection. Herein, a simple, stable, and rapid colorimetric method was firstly proposed to detect pesticide residues in vegetables based on enhancing the oxidase-mimicking activity of cube-shape Ag2O. The experiments, including fluorescence probe, electrochemistry, free radical tracking and enzymatic kinetics, confirmed that dimethoate could promote electron transfer from Ag2O to dissolved oxygen and accelerate the release of·O2- radicals as well as 1O2, facilitating the catalytic oxidation of the chromogenic substrate. The colorimetric method exhibited satisfactory sensitivity with the limit of detection as low as 14 μg·L−1. Moreover, such method showed excellent selectivity against other competitive pesticides, and achieved good recovery in several typical vegetables, which indicate that such strategy has a bright application prospect in the field of pesticide detection in food.

Persistence and Degradation Behaviour of Dimethoate in Grapes

Through a field experiment, the dissipation pattern of dimethoate in grapes was evaluated during December 2020 - February 2021. Dimethoate 30%EC was sprayed twice at ten-days interval at recommended (X) dose (445 g a.i ha-1) and double the recommended (2x) dose (890 g a.i ha-1). The samples were collected from 0 (2hr), 1, 3, 5, 7, 10, 15 and 20 days or till degradation to below detectable level (BDL) and at harvest time. The residues were extracted by the modified QuEChERS method and analyzed by LCMS. The method performance was satisfactory in terms of SANTE guidelines and with good linearity (r2&gt;0.99). The mean total dimethoate residue including omethoate was 1.047 and 2.168 mg kg-1 at x and 2x doses, respectively with half-lives of 5.47 and 5.59 days. The calculated Risk Quotient (RQ) at both x and 2x dose with Good Agricultural Practices (GAP) indicated that for dimethoate these are not safe for human health due to the intake of residue.

Combined health risk assessment of organophosphates pesticide residues in greenhouse cucumber in the Northwestern of Iran based on Monte Carlo Simulations

ABSTRACT The samples of greenhouse cucumbers were collected from the Central Fruit and Vegetable Market of Tabriz between June and December 2017. In the twenty-four cucumber samples (unwashed, washed, peeled), the residue of 18 organophosphates pesticides (OPPs) was analyzed using gas chromatography-mass spectrometry (GC-MS) following the modified QuEChERS method (quick, easy, cheap, effective, rugged and safe). Chronic non-carcinogenic risk assessment from pesticide residues in the samples was also performed for age groups of adults (women and men) and children using the Monte Carlo Simulation (MCS). Amongst the eighteen studied pesticides, eight pesticides including dimethoate, diazinon, methyl parathion, fenitrothion, chlorpyrifos, profenofos, ethion, and azinphos-methyl were detected. Pesticide residues were detected in 100% of unwashed, washed and peeled samples in the range of 0.08 to 0.37 mg.kg-1, 0.03 to 0.17 mg.kg-1 and 0.01 to 0.08 mg.kg-1, respectively. The maximum and minimum values were found for diazinon pesticides with 0.37 mg.kg-1 and profenofos and fenitrothion with 0.01 mg.kg-1. 100 % of samples contained at least three pesticide residues (dimethoate, diazinon, and methyl parathion), while 87.5% of the samples contained more pesticides residues. The residues of dimethoate, diazinon, and methyl parathion were above Maximum Residue Limits (MRL) in 100%, 83.33%, and 66.66% of samples, respectively. The identified residues were more than the EU MRLs and the IR MRLs in 100% and 95.83% samples, respectively. The mean reduction of pesticide residues in the washed and peeled samples was in the range of 37.74 to 56.52% and 66.66 to 92.30%, respectively. According to the performed risk assessment, there is no significant non-carcinogenic health risk due to the consumption of cucumber for the age group of adults. Hence, there is a considerable non-carcinogenic health risk to children due to the consumption of unwashed (HI = 2.22) and water-washed (HI = 1.36) greenhouse cucumbers.

Determination of multi-class pesticides residues of cow and human milk samples from Iran using UHPLC-MS/MS and GC-ECD: A probabilistic health risk assessment

Raw, pasteurized, powdered cow milk and human milk samples from Tehran, Iran were investigated for the residual of fifty pesticides with the aid of gas chromatography coupled with electron capture detector (GC-ECD) and mass detector for confirmation; and ultra-high performance liquid chromatography-tandem mass spectroscopy (UHPLC-MS/MS). No pesticide residue was determined in more than 91% of examined samples. However, the dimethoate residue was detected in 3 raw milk samples in levels higher than EU recommended MRL. While in 3 human milk samples, organochlorine pesticides residue, p,p′-DDT, and p,p′-DDD was recognized below MRLs, only in 1 human sample residue of p,p′-DDE was more than CODEX recommended MRL. HI in adults and children were 0.72 and 3.55, respectively. However, the health risk assessment based on HI demonstrated that adult consumers are not at considerable risk. The HI, higher than 1 in children, confirms the risks raised due to ingestion of organochlorine (OCP) and organophosphorus (OPP) pesticides via milk consumption. In addition, no carcinogenic risk to milk consumers was calculated. Therefore, implementation of good farming practices on farms, improving the knowledge and consciousness of pesticide users, use other safe methods for pest control such as biotechnology-based, and use a rational program for application of pesticides, continuous monitoring of pesticides in crops, and strict government regulations on pesticide residues in food are recommended.

Validation of Pesticides Multi-Residual Testing Method on Nutmeg by Using UPLC-MS/MS

The use of pesticides in nutmeg still leaves an accumulation of pesticide residues that can endanger human health and damage the ecological balance. In addition, nutmeg with high pesticide residue content will be rejected by nutmeg export destination countries. This research was conducted to validate the method of testing pesticide residues of carbaryl, carbofuran, acetate, and dimethoate on nutmeg. This pesticide residue test uses the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) optimization method and is analyzed using UPLC-MS/MS (Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry). This method meets the validation requirements according to SANTE/12682/2019. The limit of quantification (LOQ) of the analyte is below the Maximum Residue Limit (MRL) set by the European Union through Regulation (EC) No. 396/2005.

Monitoring of pesticide residues in vegetables collected from retail markets of Dhaka district of Bangladesh using QuEChERS Extraction and Gas Chromatography

The present study was aimed to detect and quantify major organophosphorus pesticide residues in cauliflower and cucumber collected from different retail markets of Dhaka city, Bangladesh. In this study, a total of 50 vegetable samples (30 samples of cauliflower and 20 samples of cucumber) were analyzed using Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) extraction technique and Gas Chromatography coupled with Flame Thermionic Detector (GC-FTD). Among the 30 analyzed samples of cauliflower, 5 samples (16.7% of the total number of samples) contained residues of chlorpyrifos, quinalphos, acephate and dimethoate, where 4 samples contained multiple pesticide residues. All the contaminated samples of cauliflower contained residues above the EU-MRL. On the other hand, among the 20 analyzed samples of cucumber, only 2 samples (10% of the total number of samples) contained residues of quinalphos and chlorpyrifos at a level being below the EU-MRL. This study reflects the overall scenario of pesticide residues remain in cauliflower and cucumber purchased from different local markets of Dhaka city, which will help the consumer to be aware of their health and safety. The findings derived from this study reveals the public health concern due to the potential of pesticide toxicity in vegetables for the consumers. Therefore, continuous monitoring on the use of pesticides in vegetables should be strengthened. Asian Australas. J. Food Saf. Secur. 2021, 5 (2), 63-70

Human health risk assessment through quantitative screening of insecticide residues in two green beans to ensure food safety

Food contamination with pesticide residues is a serious concern, particularly in developing countries. The study analyzed samples of country bean (Lablab purpureus L.) and yard long bean (Vigna unguiculata L.) for residues of widely used insecticides to ensure food safety. We used a modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction method followed by gas chromatography (GC)-flame thermionic detector (FTD) for quantitative estimation of pesticide residues. Mostly, the residues of chlorpyrifos, dimethoate and quinalphos were found in 11 and 14 % of country bean and yard long bean samples, respectively. About 50 % of the insecticide-contaminated bean samples contained residues above the maximum residue limit (MRL), which warrants a caution about the extensive and intensive use of pesticides in modern agriculture. The general claim of pesticide adulteration could contribute to the widespread occurrence of several insecticides in beans that threatens food safety. The assessment for chronic non-cancer health risk, based on estimated daily intake (EDI) and hazard quotient (HQ), suggests that the consumption of insecticide-contaminated beans poses potential threat to the health of adults (EDI: 2.79 × 10−4–2.96 × 10−4 and HQ: 0.56‒0.59) as well as children (EDI: 9.79 × 10−4–1.77 × 10‒3 and HQ: 1.96–3.55). Overall, our results clearly indicate that around 50 % of insecticide-contaminated bean samples, available at various local markets in Bogura district of Bangladesh, may cause health risks in humans. The present observations might help the regulatory authorities concerned in setting new guidelines for the limits of pesticide residues in commonly used bean vegetables, and in monitoring the quality of commercial formulations.

Pesticide residues in cow's milk

Quality of milk plays a key role in its wide consumption but also of its involvement in a large series of derived products, such as yogurt, cheese, butter, and ice cream. An effective LC-MS/MS method has been validated for the determination of 81 different pesticide residues in milk samples. The analyses comprised 44 milk samples collected during 2019. From all inspected pesticides, only metalaxyl (present in 11.36% samples), bifenthrin and metolachlor (9.09%), dimethoate (4.55%), prochloraz and thiacloprid were detected in 2.27% of analysed samples. The detections of trifloxystrobin and bifenthrin were above the maximum residue levels (MRLs). The Commission Regulation (EU) 2017/1135 standardizes the MRLs for dimethoate and omethoate in certain products, but a MRL for dimethoate residues in milk has not been established jet. All the other pesticide detections were below the MRLs.

Organophosphorus pesticide residues detected in eggplant and tomato samples collected from different regions of Bangladesh

The study was conducted to detect and quantify the residue of seven commonly used organophosphorus pesticides (acephate, chlorpyrifos, quinalphos, diazinon, malathion, dimethoate and fenitrothion) in eggplant and tomato samples collected from local market of commercially grown four different regions viz. Bogura, Narsingdi, Jeshore and Cumilla for the comparison between the detected residue level with maximum residue limit (MRL) set by European Union. A total of 80 analyzed samples of eggplant and tomato, 21.25% of the total number of samples contaminated with acephate, chlorpyrifos, fenitrothion and diazinon residues which were above the EU-MRLs. Out of 40 analyzed samples of eggplant, 11 samples were contaminated with acephate, diazinon fenitrothion and chlorpyrifos residues. All of the contaminated samples (27.5% of the total number of samples) had chlorpyrifos (0.02-0.046), acephate (0.017-0-0.39), diazinon (0.11-0.47) and fenitrothion (0.20) residues which were above the EU-MRLs. The eggplant samples collected from Jeshore and Narsingdi received more pesticides than Cumilla and Bogura regions. In case of 40 analyzed samples of tomato, 6 samples (15% of the total number of samples) had chlorpyrifos (0.27-0.43), diazinon (0.25) and fenitrothion (0.10) residues which were above EU-MRLs. Malathion, quinalphos and dimethoate residues were not found in any of the tested samples which might be applied at recommended doses. Asian Australas. J. Food Saf. Secur. 2021, 5 (1), 27-31

EFFECT OF HOUSEHOLD PROCESSING ON REMOVAL OF MULTI-CLASSES OF PESTICIDES FROM TOMATOES

In this paper, twenty-two pesticide residues were monitored in tomatoes.72 marketed samples were extracted and purified with QuEChERS method, and analyzed with liquid and gas Chromatography. The mean recoveries ranged from 90.75%to105.31%. The relative standard deviation was 1% to 7.5%. The limits of detection and quantification ranged from 0.0004 to 0.0231 mg.kg−1 and 0.0012 to 0.0693 mg.kg−1, and good linearity was obtained. Out of total analyzed samples, 34 samples (47.22%) were contaminated with tested pesticide residues; out of which 10 samples (13.89%) exceeded the maximum residue limits. The effects of four processing techniques (washing with tap water, washing with solution of acetic acid, peeling and boiling) on the residual pattern of five insecticides (dimethoate, carbaryl, chlorpyrifos, cypermethrin and fenvalerate) and one herbicide (2,4 dichlorophenoxy acetic acid (2,4D)) were evaluated. The reaction of the pesticides depends obviously on the physico-chemical features and also on the systemic character of the pesticides. Both of the washings lowered clearly the residues for all detected pesticides with removing up to 63.08%. Peeling was found to totally remove the residues of fenvalerate, carbaryl, cypermethrin and chlorpyrifos. Results obtained from the boiling indicated that a complete removal of 2,4D and dimethoate residues was finally achieved. In addition to that, the concentrations of cypermethrin and fenvalerate increased and processing factors above 1 were observed, the results can be seen as valuable base for monitoring of pesticides in tomatoes and supply more comprehension of residue demeanor after household processing. These implementations are important to protect consumer health from the damage of pesticide residues in food.