MRL Values Research Articles

Dissipation Kinetics, Decontamination and Safety Evaluation of Quinalphos Residues in Cauliflower Curd.

A field experiment was conducted to study the persistence and reduction of quinalphos residues in cauliflower curd by applying quinalphos 25 EC twice at 250g a.i./ha at 10 days intervals. The limit of quantification (LOQ) was 0.05µg/g, recovery ranged from 97 to 113%, and the relative standard deviation was less than 7%. The initial deposition of quinalphos residues in cauliflower curd was 1.72µg/g and reached below LOQ level after 15 days of application. Dissipation of the residue followed first-order kinetics with a half-life of 2.32 days. The reduction of quinalphos residue was evaluated using various household processes. The greatest reduction (82%) was observed when washing was followed by cooking or boiling, while the smallest reduction (55.8%) was found when washing alone was performed. A waiting period of 9 days is recommended for safe consumption of cauliflower based on the FSSAI MRL value of 0.1µg/g.

Average Run Length Computations of Autoregressive and Moving Average Process using the Extended EWMA Procedure

In the past, the control chart served as a statistical tool for detecting process changes. The Exponentially Weighted Moving Average (EWMA) control chart is highly effective for detecting small changes. This research introduces the Extended Exponentially Weighted Moving Average (Extended EWMA) control chart for the Autoregressive and Moving average process with order p = 1 and q = 1 (ARMA(1,1)) The Extended EWMA control chart incorporates two smoothing parameters ( λ1 and λ2 ) derived from the EWMA control chart. A comparative analysis of the performance of the EWMA control chart. The Average Run Length (ARL) value as determined by the explicit formulas in this research, serves as a metric for evaluating the performance of the Extended EWMA control chart and the EWMA control chart. The Numerical Integral Equation (NIE) method is used to verify the accuracy of the ARL for the explicit formulas of the two control charts which has not been before discovered. The effectiveness of control charts can also be evaluated by analyzing SDRL, ARL, MRL, RMI, AEQL, and PCI values as metrics for various design parameter values. After analyzing the results of the ARL and all five performance meters, it was determined that the Extended EWMA control chart is better than the EWMA control chart at all shift sizes of process changes. Finally, the assessment of the ARMA process is being conducted to evaluate the ARL using a dataset on PM2.5 dust levels in Bangkok, Thailand during January and February of 2024.

Distribution of Pesticides and Polychlorinated Biphenyls in Food of Animal Origin in Croatia.

Pesticides and polychlorinated biphenyls (PCBs) are persistent environmental pollutants. When entering the food chain, they can represent a public health problem due to their negative effects on health. In this study, concentrations of organochlorine pesticides (OCPs), organophosphate pesticides (OPPs), pyrethroids, carbamates, and PCBs-a total 73 compounds-were determined in a total of 2268 samples of fat tissues (beef, pork, sheep, goat, poultry, game, horse, rabbit) and processed fat, meat, and processed meat products collected in Croatia during an 8-year period. In fatty tissues, 787 results exceeded the limits of quantification (LOQ): 16 OCPs, eight OPPs, six pyrethroids, one carbamate, and seven PCBs. The most positive results in fat samples were found for OCPs, with a frequency of quantification in the range of 57.5-87.5%. Hexachlorobenzene (HCB) and dichlorodiphenyldichloroethylene (DDE) were quantified in the highest percentages, in the ranges of 5.5-66.7% and 5.4-55.8%. Concentrations above the MRL values were determined for chlorpyrifos in pork fat and for resmethrin in six fat samples and one pâté. In 984 samples of meat and meat products, only 62 results exceeded the LOQ values. The highest frequency of quantification was determined for OCPs (25 samples), of which 40% were DDT isomers (60% DDE). Frequency quantifications of PCBs in fat samples were between 7.23 and 36.7%. An evaluation of the health risk assessment showed that the consumption of fat, meat, and meat products does not pose a threat to consumer health, since all EDI values were well below the respective toxicological reference values.

Effects of Temperature on the Pharmacokinetics, Tissue Residues, and Withdrawal Times of Doxycycline in Rainbow Trout (Oncorhynchus mykiss) following Oral Administration.

The purpose of this study was to compare the pharmacokinetics, tissue residues, and withdrawal times of doxycycline after oral administration in rainbow trout reared at 10 and 17 °C. Fish received a 20 mg/kg oral dose of doxycycline after a single or 5-day administration. Six rainbow trout were used at each sampling time point for plasma and tissue samples, including liver, kidney, and muscle and skin. The doxycycline concentration in the samples was determined using high-performance liquid chromatography with ultraviolet detector. The pharmacokinetic data were evaluated by non-compartmental kinetic analysis. The WT 1.4 software program was used to estimate the withdrawal times. The increase of temperature from 10 to 17 °C shortened the elimination half-life from 41.72 to 28.87 h, increased the area under the concentration-time curve from 173.23 to 240.96 h * μg/mL, and increased the peak plasma concentration from 3.48 to 5.50 μg/mL. At 10 and 17 °C, the doxycycline concentration was obtained in liver > kidney > plasma > muscle and skin. According to the MRL values stated for muscle and skin in Europe and China (100 μg/kg) and in Japan (50 μg/kg), the withdrawal times of doxycycline at 10 and 17 °C were 35 and 31 days, respectively, for Europe and China and 43 and 35 days, respectively, for Japan. Since temperature significantly affected pharmacokinetic behavior and withdrawal times of doxycycline in rainbow trout, temperature-dependent dosing regimens and withdrawal times of doxycycline might be necessary.

Development and Application of a Physiologically Based Pharmacokinetic Model for Diclazuril in Broiler Chickens.

Withdrawal periods for diclazuril in broilers have traditionally been determined through regression analysis. However, over the last two decades, the physiologically based pharmacokinetic (PBPK) model has gained prominence as a predictive tool for veterinary drug residues, which offers an alternative method for establishing appropriate withdrawal periods for veterinary drugs. In this current study, a flow-limited PBPK model was developed to predict diclazuril concentrations in broilers following long-duration administration via medicated feed and water. This model consists of nine compartments, including arterial and venous plasma, lung, muscle, skin + fat, kidney, liver, intestine contents, and the rest of the body compartment. Physiological parameters such as tissue weights (Vcxx) and blood flow (Qcxx) were gathered from published studies, and tissue/plasma partition coefficients (Pxx) were calculated through the area method or parameter optimization. Published diclazuril concentrations were compared to the predicted values, indicating the accuracy and validity of the model. The sensitivity analysis showed that parameters associated with cardiac output, drug absorption, and elimination significantly affected diclazuril concentrations in the muscle. Finally, a Monte Carlo analysis, consisting of 1000 iterations, was conducted to calculate the withdrawal period. Based on the Chinese MRL values, we calculated a withdrawal period of 0 days for both recommended dosing regimens (through mediated water and feed at concentrations of 0.5-1 mg/L and 1 mg/kg, respectively). However, based on the European MRLs, longer periods were determined for the mediated feed dosing route. Our model provides a foundation for scaling other coccidiostats and poultry species.

Monitoring of pesticide residues in peppers from Çanakkale (Turkey) public market using QuEChERS method and LC-MS/MS and GC-MS/MS detection.

Residue analyses were conducted for 283 pesticide active ingredients on pepper samples collected from the local markets (between April and November) of Çanakkale province of Turkey by using QuEChERS method and LC-MS/MS and GC-MS/MS devices. In present pepper samples, 35 different pesticide residues were detected. About 25.0% (27 samples) of present samples had single residue and 43.5% (47 samples) had multiple residues. Of the detected pesticides, acetamiprid, triadimenol, imidacloprid, boscalid, pirimiphos-methyl, tebuconazole, and metalaxyl were the most common ones, while carbendazim/benomyl, fenpropathrin, and thiram were the banned ones. Moreover, 24 of the pesticide residues detected were above the MRL values, 19 pesticides were in the "moderately hazardous (II)," and two pesticides were in the "extremely hazardous (Ib)" class (WHO). Present findings revealed that consumer health may be in danger despite all legal measures by the Ministry of Agriculture and Forestry of Turkey, thus greater emphasis should be put on monitoring of pesticide use and residues.

Simultaneous multi-determination of pesticide residues in barberry: A risk assessment study

This research aims to analyze 57 pesticide residues in 35 ready-to-use barberry samples collected from hypermarkets in Iran by Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) approach using acetonitrile for the extraction, and surface adsorbents for clean-up procedure, followed by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). In addition, non-carcinogenic probabilistic health risk assessment was estimated by Hazard Quotient (HQ) and Hazard Index (HI) based on the Monte Carlo Simulation (MCS) method. Results demonstrated that 48.5% of samples contained pesticide residues including carbendazim, dimethoate, imidacloprid, chlorpyrifos, diazinon, fenitrothion, and fenpropathrin. Approximately 14% of the samples contained residue levels higher than MRL values including carbendazim, dimethoate, and chlorpyrifos. The highest pesticide concentration exceeding MRLs belonged to dimethoate with average residual value of 1.04 mg kg−1. The rank order of percentile 95% as health risk benchmark of HQ calculated for pesticides in adults’ consumers of barberry was dimethoate > chlorpyrifos > carbendazim with values of 5.63E-3, 2.14E-3, and 4.07E-6, respectively, while percentile 95% values of HQ in the children’s consumers were 2.64E-2, 9.97E-3, and 1.88E-5 with the same rank order. HI values in adults and children due to ingestion of barberry were 7.77E-3 and 4.63E-2, respectively. The results of this assessment demonstrated that the consumers were not at considerable non-carcinogenic risk in this commodity.

The Effects of Formulation on Imidacloprid Dissipation in Grapes and Vine Leaves and on Required Pre-Harvest Intervals under Lebanese Climatic Conditions.

In this study, imidacloprid, a systemic insecticide, currently having a specified European Commission MRL value for vine leaves (2 mg kg−1), was applied on a Lebanese vineyard under different commercial formulations: as a soluble liquid (SL) and water dispersible granules (WDG). In Lebanon, many commercial formulations of imidacloprid are subject to the same critical good agricultural practice (cGAP). It was, therefore, important to verify the variability in dissipation patterns according to matrix nature and formulation type. Random samplings of grapes and vine leaves were performed starting at 2 days until 18 days after treatment. Residue extractions were performed according to the QuEChERS method and the analytical determination using liquid chromatography coupled to tandem mass spectrometry (LC-MS-MS). The SL formulation yielded significantly higher initial deposit than the WDG formulation on grapes and vine leaves. The formulation type did not significantly affect the dissipation rates; the estimated half-lives in grapes and vine leaves were 0.5 days for all imidacloprid formulations. No pre-harvest intervals were necessary on grapes. PHIs of 3.7 days for the SL formulation and 2.8 days for the WDG formulation were estimated on vine leaves. The results showed that the type of formulation and the morphological and physiological characteristics of the matrix had an effect on the initial deposits, and thus residue levels, but not on the dissipation patterns.

Pharmacokinetics, bioavailability and withdrawal period of antibiotic oxytetracycline in catfish Pangasianodon hypophthalmus

The antibiotic oxytetracycline (OTC) has been widely used for therapeutic and preventive management of bacterial diseases in finfish and shellfish. In the present study the bioavailability, pharmacokinetics, and withdrawal period of the OTC have been determined following in-feed administration in intensively cultured catfish Pangasianodon hypophthalmus. Furthermore, the pharmacokinetic parameters of oral route were also compared with parenteral route. Drug concentrations were measured in various tissues at different time intervals by LC-MS/MS. The study revealed the drug kinetics best followed the enterohepatic circulation model with very poor bioavailability and low blood concentration after oral administration. In the withdrawal study, after 10-days of in-feed administration at the therapeutic dose the drug reached very high concentrations in the liver and kidneys but did not attain minimum inhibitory concentrations (MICs) in blood or flesh. OTC concentration also did not exceed the recommended MRL value in flesh; however, considering high amounts of the chemical in the liver and kidneys a withdrawal period of 4 days (at 28 ± 1.5 oC) is recommended for consumer safety. Poor bioavailability and non-attainment of minimum therapeutic concentration in blood and flesh do not warrant in-feed administration of OTC for control of bacterial diseases in P. hypophthalmus. Availability of data and materialsAll data generated and analyzed during this study are included in this article. Raw data may be shared upon reasonable request.

Evaluation of some heavy metal residues content in hen’s table eggs marketed in Egypt

In the present study, 120 fresh hen’s egg samples (Balady and farm) were randomly collected from supermarkets of Alexandria and El-Behera Governorates, Egypt and analyzed for lead and Cadmium residues expressed in (µg kg-1) in egg content using atomic absorption Spectrophotometer device. Results revealed that the total mean concentrations of Cd was 0.23± 0.0122 (µg kg-1) and the total mean concentration of lead was 123.45 ± 14.597(µg kg-1). Results also revealed that the residues of Cadmium in all examined samples were within the permissible limit (0.05mg kg-1) and lead (Pb) concentrations exceeded the MRL value of (0.1 mg kg-1) in 7/120 (5.83%) of the total examined eggs. Lead contamination of hen’s eggs represents a potential public health hazard, especially to children repeatedly consuming eggs from contaminated hen’s eggs. The public health hazard and adverse outcomes of the examined toxic heavy metals on human consumers were discussed. Appropriate precautions are warranted to minimize the heavy metal consumption contamination especially of lead.

On the issue of analytical control of quinone derivatives in habitats

Introduction. In the direction of normative and methodological assurance of the safety of environmental objects and imported food products, analytical approaches to the determination of a fungicide of the quinone class - dithianone in the air and citrus fruits were optimized. Materials and methods. Measurements were performed by tandem liquid mass spectrometry with a triple quadrupole mass detector (HPLC-MS/MS) in multiple reaction monitoring (MRM) mode using electrostatic spray as the ionization source. The substance from the air was concentrated on Tenax TA sorption tubes based on a porous polymer sorbent, followed by extraction of dithianone from the tubes with acetone. The preparation of samples of citrus fruits was carried out by extraction of acidified acetonitrile (selected optimal pH 2) in the presence of salts of magnesium sulfate, sodium chloride and sodium citrate two- and three-substituted, followed by centrifugation and filtration of the extract through disposable syringe membrane filters (QuEChERS technology). Results. The developed techniques were tested on real samples using the pesticide in agricultural practice. The revealed levels of dithianon do not exceed the lower limit of quantitative determination: 0.000071 mg/m3 in ambient air (with an RISL value of 0.0001 mg/m3) and 0.01 mg/kg in citrus fruits (with an established MRL value of 3 mg/kg). Conclusion. The developed methods are approved as official documents and supplement the base of analytical methods in terms of control of atmospheric air and imported food products.

Penicillin and tetracycline residues in selected fresh and UHT milk with different fat contents

The aim of the present work was to determine the residues of penicillin and tetracycline in selected fresh and UHT milk with different fat contents (< 2, 2, and > 2%). A total of 84 different milk samples (36 fresh and 48 UHT) purchased from retail chains in Silesia Region (Poland) were analysed. Penicillin and tetracycline residues were determined by the ELISA immunoenzymatic method. The obtained results were compared with MRL values adopted in Commission Regulation (EU) No. 37/2010. The results were additionally analysed statistically. Penicillin and tetracycline were found to be common in the analysed milk samples. Both antibiotics were present in low concentrations, and not exceeding their MRL. The median of penicillin residues was 0.298 µg/L, and 0.970 µg/L for tetracycline. For some samples, the determined levels of antibiotic residues did not exceed the limit of detection (LOD): three samples for penicillin (1.15%), and 24 samples for tetracycline (28.57%). A weak negative correlation between the level of penicillin and tetracycline residues was found (p = -0.218), where the decrease in penicillin concentration weakly correlated to the increase in tetracycline concentration. The level of residues of both antibiotics was significantly higher in fresh milk than in UHT milk (by 11.75% for penicillin, and 17.73% for tetracycline); for penicillin, Zcorrected = 2.445, and p = 0.0145, and for tetracycline, Zcorrected = 3.914, and p = 0.000091.

Sensitive Metal Oxide-Clay Nanocomposite Colorimetric Sensor Development for Aflatoxin Detection in Foods: Corn and Almond.

The work reports on zinc oxide bentonite nanocomposite (ZnOBt) chemical route synthesis, characterization, and investigation of curcumin (Cur) functionalization for a label-free colorimetric detection of total aflatoxins (AFs) in foods. XRD of ZnO nanoparticles (NPs) confirmed the wurtzite structure (2θ = 36.2°) and that of ZnOBt showed the intercalated interlayer composite phase. The Debye–Scherrer relation calculated the crystallite size as 20 nm (ZnO) and 24.4 nm (ZnOBt). Surface morphology by SEM exhibited flower-like hexagonal, rod-shaped ZnO NPs on the bentonite surface. Colorimetric reaction involved two-stage redox reactions between ZnOBt and dye Cur followed by AFs phenolic group and Zn(Cur)OBt. Cur gets oxidized at its diketone moiety in the presence of ZnOBt to form a red colored complex Zn(Cur)OBt, which further scavenge protons from AFs phenolic group, and gets oxidized to AFs-Zn(Cur)OBt (yellow). Binding of AFs-Zn(Cur)OBt is characterized by FT-IR ascribed to C–H bending (1966.615 cm–1), O–H stretching (3256.974 cm–1), and C=O stretching (1647.362 cm–1). 1H NMR chemical shifts (δ) (ppm) showed an increase in proton at the aliphatic region (0 to 4.4) while removal of proton in ether at 4.4 to 6 regions. Job plot calculation using UV–Vis data resulted in a higher total AF binding coefficient of Zn(Cur)OBt (Ka = 3.77 × 106 mol–1 L) compared to Zn(Cur)O (Ka = 0.645 × 106 mol–1 L) as well as a molar ratio of 1:1 by the Benesi–Hildebrand plot equation. Corn and almond food samples showed the total AFs LOD of 2.74 and 4.34 ppb, respectively. The results are validated with standard LC/MS-MS in compliance with MRL value as per the regulatory standard (EU).The NP-based method is facile and rapid and hence can be utilized for onsite detection of total AFs in foods.

Safety Evaluation of Lambda-cyhalothrin and Quinalphos in Mango (Mangifera indica L.)

Persistence of lambda-cyhalothrin and quinalphos in mango (cv. Dashehari) following their foliar application is reported. Lambda-cyhalothrin and quinalphos dissipated from 2.01 and 3.45 mg kg–1 and 1.52 and 2.78 mg kg–1 at 0 d to 0.07 and 0.11 mg kg–1 and 0.15 and 0.26 mg kg–1 at 15 and 22 d of their application at single and double doses, respectively. No residue of these insecticides was detected in mature fruit and its pulp at the time of harvest. The rate of dissipation followed first-order exponential kinetics with half-lives of 3 d for lambda-cyhalothrin and 7 d for quinalphos. Based on their MRL values of 0.5 and 0.02 mg kg–1, pre harvest intervals of 5.0 and 7.5 d for lambda-cyhalothrin and 42 and 48 d for quinalphos were suggested at the two respective rates of application. The theoretical maximum residue contribution (TMRC) values for both the insecticides were found below the maximum permissible intake (MPI) values on fruit. The residues of both the insecticides are harmless to consumers if sprayed at single dose and following the suggested PHI before consumption.

Assessment of Pb, Cd, As and Hg concentration in edible parts of broiler in major metropolitan cities of Tamil Nadu, India.

The risk of heavy metals contamination in meat and meat products is of great concern for both food safety and from human health point of view. The present study was carried out to assess the heavy metal residues such as Pb, Cd, As and Hg in broiler chicken meat, neck and edible organs (liver and kidney). In the present study, 150 samples were randomly collected from major cities (Chennai, Coimbatore, Madurai, Trichy, and Salem) of Tamil Nadu state, India and analyzed for Pb, Cd, As and Hg residues (mg/kg) using inductively coupled plasma-mass spectrometry (ICP-MS) technique. The results revealed that lead (Pb) concentration was higher in meat and liver samples of all cities and the highest concentration was detected in Chennai followed by Coimbatore, whereas in kidney and neck samples, Chennai metropolitan alone exceeded the MRL value of 0.5 and 0.1 mg/kg respectively. The residues of cadmium and mercury in meat and meat samples were within the permissible limit in all the metropolitans. Arsenic was found exceeding the MRL of 0.1 mg/kg in the breast samples of all the metropolitans (0.2141-2.2285 mg/kg, the highest being in Trichy), except for Madurai, which recorded very low value (0.0239 mg/kg). Arsenic was found in the range of 0.1110-1.0850 mg/kg in liver samples thus exceeding MRL value. Neck and kidney samples did not contain any Arsenic. Thus it can be concluded that the lead concentration in meat and edible organ samples collected from all the metropolitans exceeded the MRL values and is an indication of contamination. Appropriate precautions are warranted to minimize the heavy metal consumption contamination especially of Pb and As.

Evaluation of root traits in F2-progeny of interspecific hybrid between Lotus corniculatus “Super-Root” and tetraploid Lotus japonicus

“Super-Root” (SR) is a fast-growing root culture established in the legume forage species Lotus corniculatus that displays vigorous growth and high embryogenic capacity, uniquely allowing for continuous root cloning, direct somatic embryogenesis, and mass regeneration of plants under hormone-free culture conditions. This study’s primary aim was to verify the possibility of introducing the SR trait to another legume species as a means of enhancing root traits. Our previous research produced a F1-generation hybrid between the colchicine-doubled form of the diploid Lotus japonicus ‘Miyakojima’ MG-20 and SR-derived Lotus corniculatus. The current study’s focus was to evaluate the root phenotype of the F2-generation to confirm the introduction of SR characteristics to Lotus japonicus. We assessed 242 rooted F2-hybrid progeny using cluster analysis, concentrating on four morphological root traits: root fresh weight, total root length, maximum root length, and root diameter. Principal Component Analysis (PCA) was used to determine the correlations among eight traits of the F2-progeny of the WinRhizo root morphological measurement data and to identify what traits contributed most to their root variation. The 242-hybrid progeny and both parents were grouped into eight different clusters using a similarity phenogram. One cluster consisted of lines 36, 82, 86 and 184 that considerably exceeded the RFW, TRL, and MRL values of the L. japonicus and SR parents. The results confirmed the introduction of SR traits to the F2-hybrid progeny and identified potential candidates for breeding and gene isolation that will be conducted to expand the scope of this research.

Monitoring of Organochlorine Pesticides Residues in Five Fruits using Gas Liquid Chromatography Equipped with Electron Capture Detector (GLC-ECD)

India is the largest producer of fruits as they are important part of their economy. But they are badly affected by insect-pest attack during harvesting. Farmers use a large amount of pesticides to protect them but due to their longer persistence they found in fruits in small quantities. This paper described an analytical methodology for the monitoring of 20 organochlorine pesticides in 5 fruits viz. pineapple (Ananas comosus), apple (Malus pumila), plum (Prunus domestica), papaya (Carica papaya) and mango (Mangifera indica) by using gas liquid chromatography equipped with electron capture detector (GLC-ECD). During the monitoring work it has been found that each fruit was contaminated with pesticides. Pineapple was found contaminated with β-BHC, δ-BHC, heptachlor epoxide, dieldrin, endrin and methoxychlor; apple was found contaminated γ-BHC, δ-BHC, heptachlor epoxide, dieldrin, endrin, endosulfan II and methoxychlor; plum and papaya were found contaminated with γ-BHC, β-BHC, δ-BHC, heptachlor epoxide, 4,4′-DDE, endrin, endosulfan sulfate and methoxychlor; mango was found contaminated with β-BHC, δ-BHC, 4,4′-DDE, endrin, endosulfan sulfate and methoxychlor. However, the detected concentration of pesticides was below the MRL values but their long term use can cause serious health problems.

Residues, fate and risk assessment of spirotetramat and its four metabolites in pineapple under field conditions

ABSTRACT The aim of this study was to investigate the fate, terminal residues and risk assessment of spirotetramat and its four metabolites in pineapple and pineapple pulp samples. To achieve this goal, a simple, efficient and sensitive method based on QuEChERS technique was developed using LC-MS/MS. The limit of quantification was 0.01 mg/kg for all the target analytes with the average recoveries ranging from 77% to 109%. The validated method was successfully applied to investigate the fate and terminal residue of spirotetramat and its four metabolites in pineapple and pineapple pulp samples in China. The dissipation dynamics of spirotetramat in pineapple were investigated according to first-order kinetics and the calculated half-lives were 4.6 and 2.3 days in the two sampling locations. After two or three applications at the doses of 80 to120 mg a.i./kg, the highest spirotetramat residue (sum of spirotetramat and its four metabolites) that detected in pineapple and pineapple pulp samples were 0.203 and 0.064 mg/kg. The dietary risk assessment of spirotetramat in pineapple was assessed by risk quotients and the calculated risk quotient value was found to be far below 100%, indicating a low health risk to the consumers. As there was no recommended MRL value in pineapple in China, these results should be useful for safe and reasonable usage of spirotetramat in pineapple in China.

Prevalence of Pesticide Residues in Pond Water Samples at some Districts of Haryana

The study is assessment of pesticide residues in water bodies/ponds of agriculture intensive areas, as the principal source of pesticides in crops and animal/poultry feed are soil and water. The farmers dump the remaining pesticide solutions and wash the containers with pond water near to their fields after spraying the pesticide on their crops. These measurements can be used as baseline levels to monitor and to predict their impact on the population of the area. The determination of organochlorine (OC), pyrethroids and organophosphorous (OP) insecticide residues was carried out in the samples collected from different village ponds of six districts of Haryana and analyzed at Department of Veterinary Public Health and Epidemiology, COVS, LUVAS, Hisar. A gas chromatograph equipped with an electron capture detector (GC-ECD) for OC and pyrethroids and nitrogen phosphorous detector (GC-NPD) for OP's was employed for analysis. The testing protocol was standardized w.r.t. system precision, specificity and accuracy. The system precision values indicated a good consistency in response by the GC instrument used during present study. A good linearity was noted for standards and spiked tissue samples. Absence of interfering peaks in blank samples indicates good specificity of extraction and clean up method. Accuracy and precision of the method were in accepted range in comparison with international guidelines. Out of 50 samples, none of the sample was found to be positive for OC and Pyrethroid pesticide residues; but 16 pond water samples were detected with OP pesticide residues with prevalence rate of 32%. Monocrotophos and chlorpyriphos were detected in a maximum of eight samples each. Four samples out of 5 from Rohtak, 3 out of 5 from Jind, 3 out of 12 from Mahendergarh and 2 out of 8 from Hisar were found positive for different OP pesticide residues. All the 10 pond water samples from Ambala were found to be below detectable limit for all of the OP pesticides in study. The concentration of 16 positive samples was compared with the MRL's of drinking water, and it was observed that 4 samples, 2 each from Rohtak and Jind for monocrotophos (3.99 & 1.99 ηg/ml from Rohtak and 1.82 & 6.88 ηg/ml from Jind) violated the normal MRL values (0.5 ηg/ml). The investigation revealed that the pond water samples of Rohtak and Sirsa were found to be most contaminated with OP pesticides, mainly with Monocrotophos followed by Chlorpyriphos which indicates the excessive and irresponsible use of these pesticides in these two districts.

Article Entitled: Determination of Multi-Class Pesticide Residues in Sour Cherries by LC-MS/MS

Summary During 2018 a total of 42 sour cherry samples were collected and analysed for pesticide residues by LCMS/MS with the carbofuran–D3 and acetamiprid-D3 as internal standards. The study showed that 42.86% of the analysed samples contained pesticide residues. In percentage terms, it seems to be high, but most of the detections were below the recommended MRL values, which is encouraging. The analysis indicated that three of the analysed sour cherry samples (7.14%) contained pesticide residues above the MRLs (propiconazole, methomyl, dimethoate and prochloraz). In spite of the low concentrations, ten samples contained multiple detections, i.e. 55.56% of the analysed samples contained more than one pesticide residue.