Introduction The high crop yields obtained in agriculture at present rely on the wide use of pesticides. As a consequence, these chemicals are frequently found in soil and other environmental matrices where the risk they may pose has to be controlled [1]. Pesticides are widely used in agriculture to control pests and diseases with the goal of increasing productivity and improving the quality of products (animal or vegetable) [2]. However, the presence of pesticide residues can harm many organisms in different environmental compartments. Soil, which is a vital agricultural resource, has a high capacity to retain and store chemical substances such as pesticides. Once adsorbed onto soil particles, these compounds may be rapidly degraded or in the case of persistent chemicals, may be slowly released into the atmosphere, subterranean aquatic systems and living organisms [2]. Organic production is a system of farm management and food production that combines best environmental practices, a high level of biodiversity, the preservation of natural resources, the application of high animal welfare standards and a production method using natural substances and processes. The use of pesticides is significantly restricted, but certain plant protection products are allowed under well-defined conditions. Pesticide residue testing is one aspect of official controls on organic production [3]. The control authorities or control bodies must take and analyse samples for detecting products not authorised for organic production, for checking production techniques not allowed under organic production rules or for detecting possible contamination by products not authorised for organic production. Since January 2014, Article 65 of Regulation (EC) No 889/2008 requires that the number of samples to be taken and analysed by the control authority or designated control body every year shall correspond to at least 5% of the number of operators under its control [4]. The selection of the operators where samples have to be taken shall be based on the risk of noncompliance with the organic production rules. No criteria are established at EU level for the sampling procedures of organic products, the pesticides to be included in these checks, or the sensitivity of methods. Fileni is the third-placed player in the poultry sector on a national scale and the leading producer of organically-reared white meat in Italy. In order to be organic, the chicken should eat organic feed only, grow on organic farmland and meet all the requirements envisaged by strict applicable regulations. Thus, in this work, an analytical multiresidue method for the simultaneous determination of various classes of pesticides in soil and edible crops was developed by using HPLC-MS/MS triple quadrupole and GC-MS (specificare quali campioni analizzate in gc e quali in lc). Experimental Samples were homogenized with ceramic osterizer plus dry ice and weighed in 50 ml centrifuge tubes (5 g for edible crop and 2.5 g for soil). Then, they were hydrated with 10 ml of water at 4 ° C for 10 min, 10 ml of acetonitrile was added and samples vortexed for 1 min. Afterwards, quechers salts were added and samples vortexed again for 1 min. Then, they were centrifuged at 5000 rpm for 5 min, supernatants were transferred in the appropriate dispersive SPE pigment samples and homogenized with ceramic homogenizer and vortexed again for 1 min. The residue was filtrated through a 0.2 µm membrane filter and then directly injected into the HPLC-MS/MS or GC-MS systems. LC-MS/MS studies were performed using an Agilent 1290 Infinity II series instrument, made from an autosampler, a binary solvent pump, with a mass spectrometer (MS Agilent 6495 LC/TQ) equipped with an electrospray ionization (ESI) source. The analyte separation was achieved on a Zorbax RRHD Eclipse Plus C18 (2.1 x 150mm, 1.8 μm). The mobile phases were water (A) and methanol (B) both containing 0.1% formic acid and ammonium formate 5 mM (B) 95:5 v/v working in the gradient mode at a flow rate of 0.4 mL min-1. The solvent composition varied as follows: 0 min, 5% B; 3 min, 30% B; 17 min, 100% B; 20 min 100% B, then the column was reconditioned. The column temperature was set at 40 °C and the injection volume was 1 μL. The ESI source was operating in negative and positive ionization mode and the mass spectrometer in Dynamic MRM acquisition mode. A gas chromatograph and mass selective detector were used in combination (GC Agilent 7890B along with MS Agilent 7000C) and the separation was performed on two HP-5MS column connected each other, the dimensions of which were 30 m length x 0.25 mm id, 0.25 µm film thickness. The flow rate of helium was 6 ml⋅min-1 in splitless mode and the injector temperature was 280°C. The column temperature program began at 60°C (1 min) then increased to 170°C at 40°C•min-1, then increased to 310°C at 10°C min. The mass spectrometer used the electron impact (EI) mode with an ionisation voltage of 70 eV, and the scan ion monitoring (SCAN) mode to produce the spectra of the separated compounds. Results After method validation, 173 soil samples and 128 different edible crop were analysed. In soil, in only seven samples nine different pesticides were found, i.e. clortoluron, p,p'-DDE, imidacloprid, azoxystrobin, oxadiazon, tetraconazolo, cyproconazole, difenoconazole and metalaxyl at levels ranging from 18 to 111 µg L-1. In edible crop, in only six samples six different pesticides were found, i.e. terbutilazina, pyraclostrobin, tebuconazolo, azoxystrobin tetraconazolo and cyproconazole at levels ranging from 11 to 147 µg L-1. Conclusions In this work, an analytical multiresidue method for the simultaneous determination of various classes of pesticides in soil and edible crops was developed by using HPLC-MS/MS triple quadrupole and GC-MS (specificare quali campioni analizzate in gc e quali in lc). A high number of samples were analysed, i.e. 173 soil samples and 128 different edible crops, and only 7 soil and 6 edible crop samples pesticide were detected in low amount. References 1. C. Sanchez-Brunete, B. Albero, J.L. Tadeo; Journal of Agricultural and.Food Chemistry, 52 (2004), pp 1445-1451. 2. C.E.S. Soarea, A.A. Neves, M.E.L.R. Queiroz, A.F. Oliveira, R.C. Assis, R.C. Assis; J. Braz. Chem. Soc. 26 (2015), pp 1790-1797. 3. Overview report Pesticide Residue Control in Organic Production DG Health and Food Safety. Eurpopean Commission, Electronic version ISSN 2315-2168 ISBN 978-92-79-53001-2 doi:10.2875/35178 Catalogue number: EW-BC-15-051-EN-N 4. REGULATIONS COMMISSION REGULATION (EC) No 889/2008 of 5 September 2008 laying down detailed rules for the implementation of Council Regulation (EC) No 834/2007 on organic production and labelling of organic products with regard to organic production, labelling and control
Multiresidue determination of pesticides in soil and edible crops by using HPLC-MS/MS triple quadrupole.
Giovanni Caprioli;Manuela Cortese;Massimo Ricciutelli;Dennis Fiorini;Gianni Sagratini.
2019-01-01
Abstract
Introduction The high crop yields obtained in agriculture at present rely on the wide use of pesticides. As a consequence, these chemicals are frequently found in soil and other environmental matrices where the risk they may pose has to be controlled [1]. Pesticides are widely used in agriculture to control pests and diseases with the goal of increasing productivity and improving the quality of products (animal or vegetable) [2]. However, the presence of pesticide residues can harm many organisms in different environmental compartments. Soil, which is a vital agricultural resource, has a high capacity to retain and store chemical substances such as pesticides. Once adsorbed onto soil particles, these compounds may be rapidly degraded or in the case of persistent chemicals, may be slowly released into the atmosphere, subterranean aquatic systems and living organisms [2]. Organic production is a system of farm management and food production that combines best environmental practices, a high level of biodiversity, the preservation of natural resources, the application of high animal welfare standards and a production method using natural substances and processes. The use of pesticides is significantly restricted, but certain plant protection products are allowed under well-defined conditions. Pesticide residue testing is one aspect of official controls on organic production [3]. The control authorities or control bodies must take and analyse samples for detecting products not authorised for organic production, for checking production techniques not allowed under organic production rules or for detecting possible contamination by products not authorised for organic production. Since January 2014, Article 65 of Regulation (EC) No 889/2008 requires that the number of samples to be taken and analysed by the control authority or designated control body every year shall correspond to at least 5% of the number of operators under its control [4]. The selection of the operators where samples have to be taken shall be based on the risk of noncompliance with the organic production rules. No criteria are established at EU level for the sampling procedures of organic products, the pesticides to be included in these checks, or the sensitivity of methods. Fileni is the third-placed player in the poultry sector on a national scale and the leading producer of organically-reared white meat in Italy. In order to be organic, the chicken should eat organic feed only, grow on organic farmland and meet all the requirements envisaged by strict applicable regulations. Thus, in this work, an analytical multiresidue method for the simultaneous determination of various classes of pesticides in soil and edible crops was developed by using HPLC-MS/MS triple quadrupole and GC-MS (specificare quali campioni analizzate in gc e quali in lc). Experimental Samples were homogenized with ceramic osterizer plus dry ice and weighed in 50 ml centrifuge tubes (5 g for edible crop and 2.5 g for soil). Then, they were hydrated with 10 ml of water at 4 ° C for 10 min, 10 ml of acetonitrile was added and samples vortexed for 1 min. Afterwards, quechers salts were added and samples vortexed again for 1 min. Then, they were centrifuged at 5000 rpm for 5 min, supernatants were transferred in the appropriate dispersive SPE pigment samples and homogenized with ceramic homogenizer and vortexed again for 1 min. The residue was filtrated through a 0.2 µm membrane filter and then directly injected into the HPLC-MS/MS or GC-MS systems. LC-MS/MS studies were performed using an Agilent 1290 Infinity II series instrument, made from an autosampler, a binary solvent pump, with a mass spectrometer (MS Agilent 6495 LC/TQ) equipped with an electrospray ionization (ESI) source. The analyte separation was achieved on a Zorbax RRHD Eclipse Plus C18 (2.1 x 150mm, 1.8 μm). The mobile phases were water (A) and methanol (B) both containing 0.1% formic acid and ammonium formate 5 mM (B) 95:5 v/v working in the gradient mode at a flow rate of 0.4 mL min-1. The solvent composition varied as follows: 0 min, 5% B; 3 min, 30% B; 17 min, 100% B; 20 min 100% B, then the column was reconditioned. The column temperature was set at 40 °C and the injection volume was 1 μL. The ESI source was operating in negative and positive ionization mode and the mass spectrometer in Dynamic MRM acquisition mode. A gas chromatograph and mass selective detector were used in combination (GC Agilent 7890B along with MS Agilent 7000C) and the separation was performed on two HP-5MS column connected each other, the dimensions of which were 30 m length x 0.25 mm id, 0.25 µm film thickness. The flow rate of helium was 6 ml⋅min-1 in splitless mode and the injector temperature was 280°C. The column temperature program began at 60°C (1 min) then increased to 170°C at 40°C•min-1, then increased to 310°C at 10°C min. The mass spectrometer used the electron impact (EI) mode with an ionisation voltage of 70 eV, and the scan ion monitoring (SCAN) mode to produce the spectra of the separated compounds. Results After method validation, 173 soil samples and 128 different edible crop were analysed. In soil, in only seven samples nine different pesticides were found, i.e. clortoluron, p,p'-DDE, imidacloprid, azoxystrobin, oxadiazon, tetraconazolo, cyproconazole, difenoconazole and metalaxyl at levels ranging from 18 to 111 µg L-1. In edible crop, in only six samples six different pesticides were found, i.e. terbutilazina, pyraclostrobin, tebuconazolo, azoxystrobin tetraconazolo and cyproconazole at levels ranging from 11 to 147 µg L-1. Conclusions In this work, an analytical multiresidue method for the simultaneous determination of various classes of pesticides in soil and edible crops was developed by using HPLC-MS/MS triple quadrupole and GC-MS (specificare quali campioni analizzate in gc e quali in lc). A high number of samples were analysed, i.e. 173 soil samples and 128 different edible crops, and only 7 soil and 6 edible crop samples pesticide were detected in low amount. References 1. C. Sanchez-Brunete, B. Albero, J.L. Tadeo; Journal of Agricultural and.Food Chemistry, 52 (2004), pp 1445-1451. 2. C.E.S. Soarea, A.A. Neves, M.E.L.R. Queiroz, A.F. Oliveira, R.C. Assis, R.C. Assis; J. Braz. Chem. Soc. 26 (2015), pp 1790-1797. 3. Overview report Pesticide Residue Control in Organic Production DG Health and Food Safety. Eurpopean Commission, Electronic version ISSN 2315-2168 ISBN 978-92-79-53001-2 doi:10.2875/35178 Catalogue number: EW-BC-15-051-EN-N 4. REGULATIONS COMMISSION REGULATION (EC) No 889/2008 of 5 September 2008 laying down detailed rules for the implementation of Council Regulation (EC) No 834/2007 on organic production and labelling of organic products with regard to organic production, labelling and controlI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
