Pesticide Residues In Soil Samples Research Articles

Concentration and non-dietary human health risk assessment of pesticide residues in soil of farms in Golestan province, Iran

ABSTRACT Detection of pesticide residues in soil samples was conducted using UHPLC-MS/MS. Non-dietary health risk assessment was conducted using calculate chronic daily intake (CDI) from ingestion, inhalation and dermal contact pathways and following non-carcinogenic and carcinogenic risks in the adults and adolescent. The rank order of pesticide in soil based on their concentration was malathion (0.082 mg kg−1)> cyproconazole (0.019 mg kg−1)> propargite (0.018 mg kg−1)> butachlor (0.016 mg kg−1) > chlorpyrifos (0.0067 mg kg−1)> diazinon (0.0014 mg kg−1)> imidacloprid (0.0007 mg kg−1). Hazard index (HI) values obtained of exposure to pesticides in soil in adults and adolescent were 0.0012 and 0.0035, respectively. Hence, exposed population are at the acceptable range of non-carcinogenic risk (HI < 1). Cancer risk (CR) values due to propargite in soil via ingestion pathway in adults and adolescent were 2.03E–09 and 2.08E–09, respectively; therefore, carcinogenic risk due to the exposure to pesticide contaminated soil was safe range (CR < 1E–06).

Target and suspect screening of pesticide residues in soil samples from peach orchards using liquid chromatography quadrupole time-of-flight mass spectrometry

Agricultural soil contamination by pesticide residues has become a serious issue of increasing concern due to their high persistence and toxicity to non-target species. However, as the world’s largest peach producer, national scale surveys on pesticide residues in peach orchard soils are scarce in China. In this study, a target and suspect screening method covering over 200 pesticides commonly used in peach orchards was developed using ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry in MSE. An identification strategy using different data processing parameters was developed to identify the pesticide occurrence in soil. The method was applied to soil samples from typical peach orchards in 12 regions across China. The present work also discusses in detail the frequency of occurrence, concentration of pesticides, spatial distribution of multiresidues, and relationship between pesticide occurrence and soil properties. In the tested soil samples, 21 herbicides (level 1), 31 fungicides (level 2a), 24 insecticides (level 2a), and 3 growth regulators (level 2a) were identified. The total concentrations of quantifiable herbicides in the soil samples ranged from 1.05 to 327 ng/g. Only in 5.4% of the soil samples, no pesticide residues were present. By contrast, more than 86% of the total contained multiple residues. This study represents the first large-scale survey of pesticides in soil from peach orchards and provides comprehensive and accurate information on the pesticide residue status for risk assessment.

Target and Suspect Screening of Pesticide Residues in Soil Samples from Peach Orchards Using Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry

Target and Suspect Screening of Pesticide Residues in Soil Samples from Peach Orchards Using Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry

Pesticide residues in soil samples from vegetable growing area of Bihar

The surface soil samples (0-15 cm) were found contaminated with different pesticides in vegetable growing areas in Bihar. Total twenty samples were analysed in which HCH and endosulfan were found as the major contaminants of soil. Nine samples were found contaminated with HCH (ND-0.055mg kg-1) and ten with endosulfan (ND-0.078mg kg-1). DDT residues were detected only in three soil samples. Among the organophosphate pesticide, residues of quinalphos (ND-0.062mg kg-1) and chlorpyriphos (ND-0.037mg kg-1) were detected in five samples each while dimethoate present in only one sample. Residues of cypermethrin, fenvalerate and deltamethrin were also detected in four, three and one soil sample, respectively.

Process Intensification of Dichlorodiphenyltrichloroethane Detection Methods for Determining Trace Concentrations in Soils

Dichlorodiphenyltrichloroethane (DDT) residue in Ontario soil is expected to be found at trace levels, since it has been banned for over 45 years in Canada. This presents challenges to the efficiency and accuracy of conventional detection methods. This study intensified the conventional DDT detection method, in the characterization of aged soil samples collected from historically-treated sites in Ontario. Recovery, time consumption, and labor intensity were considered for the intensification evaluation. Ultrasonic probe extraction was found to significantly shorten the extraction time, with similar yield compared to ultrasonic water bath extraction and homogenized extraction. Homogenized extraction for 24 h following ultrasonic probe extraction can increase yield over 27%. Rotary evaporator concentration was used, since it can reduce the operating time with comparable recovery. The Florisil clean-up column used in the conventional method was removed from the intensified method, due to its negligible effect and high time consumption. The intensified method may be valuable for further investigation to determine other trace level organochlorine pesticide residues in soil samples.

Front Cover: Simultaneous determination of seven pesticide residues in soil samples using ultrasound‐assisted dispersive solid‐phase extraction combined with UHPLC‐MS/MS

Front Cover: Simultaneous determination of seven pesticide residues in soil samples using ultrasound‐assisted dispersive solid‐phase extraction combined with UHPLC‐MS/MS

Simultaneous determination of seven pesticide residues in soil samples using ultrasound‐assisted dispersive solid‐phase extraction combined with UHPLC–MS/MS

AbstractA novel and reliable method for the determination of seven pesticide residues (hexaconazole, flutriafol, triadimenol, tebuconazole, diniconazole, fipronil and picoxystrobin) in soil samples was developed by using ultrasound‐assisted dispersive solid‐phase extraction combined with ultra high performance liquid chromatography and tandem mass spectrometry. In this approach, the target analytes were first extracted from the soil samples into acetonitrile, and the ultrasound technique was applied to increase the extraction efficiency. Next, a dispersive solid‐phase extraction purification step was performed by directly adding adsorbents into the extraction solution. The effects of various parameters on the extraction efficiency of the proposed method were investigated and optimized. Under optimum conditions, the calibration curves showed good linearity in the range of 0.25–250 (hexaconazole, diniconazole and tebuconazole), 0.5–500 (flutriafol, triadimenol and fipronil) and 0.05–200 ng g−1 (picoxystrobin) with the correlation coefficients higher than 0.9994. The limits of detection and quantification for the present method were 0.01–0.08 and 0.03–0.25 ng g−1, respectively. The recoveries of the target analytes ranged from 69.5 to 105.9%. The full procedures were applied for the preconcentration and subsequent determination of seven pesticides in four kinds of real soil samples (corn soil, herbs soil, cucumis melo soil and city lawn soil), and satisfactory results were obtained.

A preliminary study of the content and distribution of pesticide residues in soil samples from the Kathmandu valley, Nepal .

The increasing use of pesticides for agricultural production is causing soil pollution problems in different parts of Nepal. Uncontaminated agricultural soils are of great importance as they have a direct impact on food security and human health. The objective of this study was to investigate the quality and quantity of pesticides in soil samples from districts near the capital city of Kathmandu, from where fruit and vegetables are brought to the city for consumption. A questionnaire survey was carried out in four districts around Kathmandu city to investigate the types of pesticides that are most commonly used in these districts. A total of 15 soil samples were taken at a depth of 10 cm and four complete soil profiles were sampled at three different depths (10 cm, 30 cm and 50 cm) on the farms of those who were interviewed. A total of four replicates of each soil sample were extracted and analyzed. The pH, soil texture and organic carbon content of the soil samples were analyzed to understand the general soil characteristics. The QuEChERS method used for the analysis of food samples was modified and applied to the soil samples. An HPLC-MS/MS was used for the qualification and quantification of the pesticide residues in the soil samples. The questionnaire survey revealed that carbendazim, chlorpyrifos-methyl, parathion-methyl, imidacloprid, metalaxyl, dimethoate, omethoate and dichlorvos were the most commonly used pesticides in the area studied. The chemical analysis showed that soil samples from all the districts except Kathmandu city were contaminated with various pesticides. The soil samples collected at the depth of 10 cm were found to be contaminated with the fungicide carbendazim and the insecticide chlorpyrifos-methyl at rates of up to 0.038 mg kg&lt;sup&gt;-1&lt;/sup&gt; and the systemic insecticide imidacloprid was found at up to 0.016 mg kg&lt;sup&gt;-1&lt;/sup&gt;. The study of soil samples taken at different depths (10 cm, 30 cm and 50 cm) showed that pesticides were homogenously distributed with soil depth. The recovery between 77.5-112%, linearity between 0.01 mg kg&lt;sup&gt;-l&lt;/sup&gt; - 2 mg kg&lt;sup&gt;-l&lt;/sup&gt; with correlation factors R2 higher than 0.99 and LOQ between 0.2 µg kg&lt;sup&gt;-1&lt;/sup&gt;- 6.25 µg kg&lt;sup&gt;-l&lt;/sup&gt; were found. Some samples were contaminated with parathion-methyl, a highly carcinogenic organophosphorous insecticide, even though these pesticides had already been banned. For the first time, this study provides information about soil contamination levels due to pesticides in Central Nepal and shows that further research and information campaigns for farmers are necessary.

Enantioselective Degradation of Dufulin in Four Types of Soil

In this study, enantioselective degradation of dufulin in four types of soil (Guiyang silty loam, Nanning silty clay, Hefei silty clay, and Harbin silty clay) was investigated under sterile and nonsterile conditions. Pesticide residues in soil samples were extracted with acetonitrile. S-(+)-Dufulin and R-(-)-dufulin were separated and determined on an amylose tris(3,5-dimethylphenylcarbamate) (Chiralpak IA) chiral column by normal phase high-performance liquid chromatography (HPLC). The absolute configurations of dufulin enantiomers were determined by obtaining experimental and computed circular dichroism spectra. Dufulin enantiomers were found to be configurationally stable in the selected soils, and no interconversion was observed during the incubation of enantiopure S-(+)- or R-(-)-dufulin under nonsterile conditions. Compared to the half-life (t1/2) of dufulin in sterile soils, the degradation rate was higher in nonsterile soils, which suggests that dufulin degradation can be attributed primarily to microbial activity in soils used for agricultural cultivation. Furthermore, enantiopure S-(+)-dufulin degraded more rapidly than its antipode. This suggests that use of enantiopure S-(+)-dufulin could exert less disturbance to soil bioactivity and contribute less to environmental pollution.

RESIDU PESTISIDA ALDRIN DAN DIELDRIN PADA SAMPEL TANAH DAN AIR DI DESA SRIGADING KECAMATAN SANDEN KABUPATEN BANTUL

Aldrin and dieldrin pesticide residue in soil and water samples from Srigading Village, Sanden District, Bantul Regency has been investigated. The purpose of this study were to analyze, identificate and evaluate pyrethroid pesticide residues in soil and water samples. Soil sample was extracted using shaker with acetone solvent. Water samples was extracted using separator funnel with 15% (v/v) dichloromethane/n-hexane solvent.Clean-up was couducted using chromatography column using florisil and determination of pesticide residue in the samples was carried out by gas chromatography apparatus equipped with electron capture detector (GC-ECD). The result showed that pesticide residues in soil sample in the range level: aldrin (4,8-64,8 ppb) and dieldrin (not detected-6,0 ppb). In water sample pesticide residues in the range level: aldrin (not detected-1,0 ppb) dan dieldrin (-not detected1,2 ppb). The quality or water sample taken from onion field is laid under the standard of water that has been settled.

A preliminary study of the content and distribution of pesticide residues in soil samples from the Kathmandu valley, Nepal

A preliminary study of the content and distribution of pesticide residues in soil samples from the Kathmandu valley, Nepal

Enantioselective Analysis and Degradation Studies of Isocarbophos in Soils by Chiral Liquid Chromatography–Tandem Mass Spectrometry

An enantioselective method is presented for the determination of isocarbophos in soil by liquid chromatography coupled with tandem mass spectrometry. The pesticide residues in soil samples were extracted with acetonitrile, and complete enantioseparation was obtained on an amylose tris(3,5-dimethylphenylcarbamate) chiral column using acetonitrile/2 mM ammonium acetate solution containing 0.1% formic acid (60:40, v/v) as the mobile phase. The absolute configuration of isocarbophos enantiomers was determined by the combination of experimental and calculated electronic circular dichroism spectra. The method was utilized to investigate the degradation of isocarbophos in soils (Changchun, Hangzhou, and Zhengzhou) under sterilized or native conditions. Isocarbophos enantiomers were configurationally stable in the selected soils, and the pesticide degradation was not enantioselective in the sterilized condition. The degradation behavior of rac-isocarbophos was different under native conditions, with no enantioselectivity in the Changchun soil and with the S-(+)-isocarbophos enriched in the Hangzhou and Zhengzhou soils.

Solid phase microextraction (SPME) in determination of pesticide residues in soil samples

The basic principles and application possibilities of the methods based on solid phase microextraction (SPME) in the analysis of pesticide residues in soil samples are presented in the paper. The most important experimental parameters which affect SPME efficacy in pesticide determination (type and thickness of microextraction fiber, duration of microextraction, temperature at which it is conducted, effect of addition of salts (the effect of efflorescence), temperature and time of desorption, the choice of optimal solvent for pesticide exctraction from the soil and the optimal number of extraction steps), as well as general guidelines for their optimization are also shown. In the end, current applications of SPME methods in the analysis of pesticide residues in soil samples are presented.

Determination of Two Pesticides in Soils by Dispersive Liquid–Liquid Microextraction Combined with LC-Fluorescence Detection

In the present work, a simple, rapid and sensitive sample pre-treatment technique, dispersive liquid–liquid microextraction (DLLME) coupled with liquid chromatography-fluorescence detection (LC-FLD), has been developed to determine carbamate (carbaryl) and organophosphorus (triazophos) pesticide residues in soil samples. Methanol was first used as extraction solvent for the extraction of pesticides from the soil samples and then as dispersive solvent in the DLLME procedure. Under the optimum extraction conditions, the linearity was obtained in the concentration range of 0.1–1,000 ng g−1 for carbaryl and 1–5,000 ng g−1 for triazophos, respectively. Correlation coefficients varied from 0.9997 to 0.9999. The limits of detection (LODs), based on signal-to-noise ratio (S/N) of 3, ranged from 14 to 110 pg g−1. The relative standard deviation (RSDs, for 20.0 ng g−1 of each pesticide) varied from 1.96 to 4.24% (n = 6). The relative recoveries of two pesticides from soil A1, A2 and A3 at spiking levels of 10.0, 20.0 and 50.0 ng g−1 were in the range of 88.2–108.8%, 80.8–110.7% and 81.0–111.1%, respectively. The results demonstrated that DLLME was a sensitive and accurate method to determine the target pesticides, at trace levels, in soils.

A simplified liquid-solid extraction technique for the analyses of pesticide residues in soil samples.

A simplified liquid-solid extraction technique was studied for the analyses of pesticide residues in soil samples. It is a simple, one step sample preparation method based on a relative quantification concept. Linear response curves were obtained for all of the target compounds regardless of their surface adsorption. This observation was explained and modeled to obey Langmuir adsorption Equation. The adsorption of analytes onto the sample surfaces will sacrifice the detection sensitivity. The strategies to reduce the surface adsorption, such as, molecular replacement and selection of solvents, were discussed. The relative quantification and the wide varieties of available solvents would enable the technique to be a useful method for the monitoring and analyses of pesticide residues in soils.

Pesticide residues in the top soil of five West Alabama counties.

The types and levels of pesticide residues in soil samples from five west Alabama counties were determined. Soil samples were taken randomly from preselected sites in each county and were analyzed by gas chromatography. Pesticide residues were found in all samples examined, even soil samples from areas where records indicated that no pesticides had been applied directly. The most prevalent chlorinated hydrocarbons were benzene hexachloride and aldrin while the most abundant organophosphate was malathion.