Showing papers by "Ministry of Agriculture published in 2012"

Co-occurrence of aflatoxins B₁, B₂, G₁ and G₂, ochratoxin A, zearalenone, deoxynivalenol, and citreoviridin in rice in Brazil.

Abstract: A total of 230 samples of processed rice and its sub-products or derived products were analysed to establish the co-occurrence of several mycotoxins. Samples were analysed in the period 2007–2009 due to the outbreak of beriberi associated with the consumption of rice stored in inappropriate conditions in Brazil. According to data from the Ministry of Health, 323 cases of disease were registered in 2006, of which at least 47 cases resulted in death. The occurrence of total aflatoxin (AFT) (aflatoxin B1 + B2 + G1 + G2), ochratoxin A (OTA), zearalenone (ZON), deoxynivalenol (DON), and citreoviridin (CTV) was 58.7%, 40.0%, 45.2%, 8.3% and 22.5%, respectively. From 166 rice samples analysed, 55% had levels <0.11 µg kg−1 for AFT. For OTA and ZON, of 165 rice samples analysed, 28% and 29% were contaminated with levels from 0.20 to 0.24 µg kg−1 and from 3.6 to 290.0 µg kg−1, respectively. One sample (0.6%) was contaminated with 4872.0 µg kg−1 of ZON. A total of 91% of rice samples (n = 165) did not contain detect...

Simultaneous determination of chloramphenicol and florfenicol in liquid milk, milk powder and bovine muscle by LC-MS/MS.

Abstract: A validated method based on European and Brazilian legislation is reported. It is applicable to the simultaneous determination of chloramphenicol (CAP) and florfenicol (FF) by LC-MS/MS in liquid milk, milk powder and bovine muscle. The chromatographic analysis is completed in 6 min and the extraction procedure is very simple, involving only one step liquid-extraction with ethyl acetate. Where it proved necessary to include clean-up, an efficient and rapid step using C18-dispersive solid was added. Initially, a complete validation was performed with liquid milk matrix; later the scope was extended to the other matrices through extending the inter-day precision (within laboratory reproducibility) RSD values. An internal standard (d(5)-CAP) was employed for quantitative purposes. The method was shown to have good accuracy and precision for determining CAP residues at the level of 0.3-0.6 g kg(-1) and FF residues at the level of 5-15 µg kg(-1).

β-lactam antibiotics residues analysis in bovine milk by LC-ESI-MS/MS: a simple and fast liquid–liquid extraction method

Abstract: This study presents the development and validation of a simple method for the detection and quantification of six β-lactam antibiotics residues (ceftiofur, penicillin G, penicillin V, oxacillin, cloxacillin and dicloxacillin) in bovine milk using a fast liquid-liquid extraction (LLE) for sample preparation, followed by liquid chromatography-electrospray-tandem mass spectrometry (LC-MS/MS). LLE consisted of the addition of acetonitrile to the sample, followed by addition of sodium chloride, centrifugation and direct injection of an aliquot into the LC-MS/MS system. Separation was performed in a C(18) column, using acetonitrile and water, both with 0.1% of formic acid, as mobile phase. Method validation was performed according to the criteria of Commission Decision 2002/657/EC. Limits of detection ranged from 0.4 (penicillin G and penicillin V) to 10.0 ng ml(-1) (ceftiofur), and linearity was achieved. The decision limit (CCα), detection capability (CCβ), accuracy, inter- and intra-day repeatability of the method are reported.

Determination and confirmation of chloramphenicol in honey, fish and prawns by liquid chromatography–tandem mass spectrometry with minimum sample preparation: validation according to 2002/657/EC Directive

Abstract: A reliable, simple and sensitive liquid chromatography–electrospray ionisation-tandem mass spectrometry (LC–ESI-MS/MS) confirmation method has been developed for chloramphenicol (CAP) determination in honey, fish and prawns. For honey, samples were extracted with ethyl acetate, an aliquot was evaporated to dryness and re-dissolved in mobile phase. For fish and prawns, tissues were extracted with acetonitrile and chloroform. The organic layer was evaporated to dryness and the residue was re-constituted with water: acetonitrile (90:10). LC separation was achieved on a C18 column with gradient elution using a mobile phase of acetonitrile and water. Analysis was carried out on a triple–quadrupole tandem mass spectrometer in multiple reaction monitoring (MRM) mode via electrospray interface operated in negative ionisation mode, with deuterated chloramphenicol-d5 (d5-CAP) as internal standard. Method validation was performed according to the criteria of Commission Decision 2002/657/EC. Four identification point...

High-throughput multiclass screening method for antibiotic residue analysis in meat using liquid chromatography-tandem mass spectrometry: a novel minimum sample preparation procedure

Abstract: A multiresidue and multiclass method based on liquid chromatography-tandem mass spectrometry for the determination of antibacterials was developed and validated for screening purposes. This method can be applied to commonly used drugs in veterinary medicine such as tetracyclines, quinolones and sulfonamides. Sample preparation consists in cell disruption with sand (previously purified and washed with EDTA 100 mM) followed by protein precipitation with acidified acetonitrile. Validation was conducted in accordance to European Union requirements (2002/657/EC) for qualitative methods covering detection capability (CCβ), selectivity, specificity and stability. The method enabled the detection of 21 different drugs and had a false-compliant rate of <5% (β error) at between 25% and 50% of the maximum residue levels established by legal authorities. The methodology was successfully applied to incurred poultry samples.

Detection of airborne genetically modified maize pollen by real‐time PCR

Abstract: The cultivation of genetically modified (GM) crops has raised numerous concerns in the European Union and other parts of the world about their environmental and economic impact. Especially outcrossing of genetically modified organisms (GMO) was from the beginning a critical issue as airborne pollen has been considered an important way of GMO dispersal. Here, we investigate the use of airborne pollen sampling combined with microscopic analysis and molecular PCR analysis as an approach to monitor GM maize cultivations in a specific area. Field trial experiments in the European Union and South America demonstrated the applicability of the approach under different climate conditions, in rural and semi-urban environment, even at very low levels of airborne pollen. The study documents in detail the sampling of GM pollen, sample DNA extraction and real-time PCR analysis. Our results suggest that this 'GM pollen monitoring by bioaerosol sampling and PCR screening' approach might represent an useful aid in the surveillance of GM-free areas, centres of origin and natural reserves.

Essential steps to providing reliable results using the Analytical Quality Assurance Cycle

Abstract: Considering how demand for quality assurance (QA) has grown in analytical laboratories, we show the trends in analytical science, illustrated through international standard ISO/IEC 17025, validation, measurements of uncertainty, and quality-control (QC) measures A detailed review of the history of analytical chemistry indicates that these concepts are consistently used in laboratories to demonstrate their traceabilities and competences to provide reliable results We propose a new approach for laboratory QA, which also develops a diagram to support routine laboratories (which generally apply a quality system, such as ISO/IEC 17025) or research laboratories (that have some difficult applying this international standard) This approach, called the Analytical Quality Assurance Cycle (AQAC), presents the major QA concepts and the relationships between these concepts in order to provide traceability and reliable results The AQAC is a practical tool to support the trend towards QA in analytical laboratories

The prevalence and spatial epidemiology of cysticercosis in slaughtered cattle from Brazil.

Abstract: Cisticercose bovina e uma doenca endemica em varios paises com um importante potencial zoonotico e uma crescente importância na saude publica. A inspeccao da carne nos matadouros e fundamental para estabelecer a prevalencia e prevencao de doencas zoonoticas, tais como a cisticercose. No entanto, no Brasil, nao ha estudo que tenha investigado a dinâmica da cisticercose em bovinos abatidos em todo o pais. Assim, o presente estudo teve como objetivo usar Sistema de Informacao Geografica (GIS) como uma ferramenta para analisar a prevalencia de cisticercose bovina em bovinos, usando os dados de matadouros inspecionados pelo Servico de Inspecao Federal do Ministerio da Agricultura, Pecuaria e Abastecimento (SIF/MAPA), no periodo de janeiro de 2007 a abril de 2010. As informacoes de bovinos abatidos foram usadas para gerar um banco de dados sobre cisticercose bovina para todos os estados e municipios do Brasil, a fim de analisar e criar mapas epidemiologicos usando o software GIS. Durante o periodo analisado, 75.983.590 bovinos foram abatidos e a prevalencia de cisticercose bovina no Brasil foi de 1,05%, com a regiao Sudeste apresentando a maioria dos casos. A maior quantidade de casos cisticercose bovina ocorreram no estado de Sao Paulo (400.834), seguido por Mato Grosso do Sul (151.735) e Parana (94.046), enquanto nao houve observacao de ocorrencia em nove estados. Os dados fornecidos por matadouros inspecionados pelo SIF/MAPA podem ser usados como uma fonte informativa para animais e agencias de saude publica para a prevencao do complexo teniase/cisticercose. Este estudo elucida a importância da inspeccao da carne associado aos mapas epidemiologicos, visando o controle da doenca nos rebanhos bovinos e a vigilância ativa para infeccao zoonotica potencial para humano. Os dados deste estudo sugerem que a cisticercose bovina e endemica em varios estados brasileiros, e o risco de infeccao esta diretamente relacionado com as principais areas de criacao de bovinos, independentemente da demografia da populacao humana.

Optimisation and validation of a quantitative and confirmatory LC-MS method for multi-residue analyses of β-lactam and tetracycline antibiotics in bovine muscle

Abstract: A multi-residue method for the determination of the β-lactam antibiotics ampicillin, cefazolin, cloxacillin, dicloxacillin, nafcillin, oxacillin, penicillin G, penicillin V and the tetracyclines chlotetracycline, tetracycline and oxytetracycline was optimised and validated in bovine muscle. The method is based on the extraction of the residues from muscle using water/acetonitrile (2/8, v/v) with subsequent use of dispersive solid-phase C18 and hexane for purification. Extracts were analysed using ultra-performance liquid chromatography (UPLC-MS/MS) coupled with the mass spectrometer in positive electrospray ionisation mode (ESI+) for all analytes. The method was validated according to the requirements of European Commission Decision 2002/657/EC. The validation results were obtained within the MRL range of 0-1.5 of the MRL, with recoveries varying from 90% to 110% and CV < 20% (n = 54), except for cloxacillin, dicloxacillin and nafcillin. However, matrix interference was observed. The decision limit (CCα) ranged from 10% to 15% of the MRL. The uncertainty measurement was estimated based on both bottom-up and top-down strategies and the uncertainty values were found to be lower than 20% of the MRL. The method has a simple extraction procedure whereby analytes are separated with reasonable resolutions in a single 11-min chromatographic run. According to the validation results, this method is suitable for monitoring β-lactams and tetracyclines according to National Program for Residue and Contaminant Control - Brazil (NPRC-Brazil) in bovine muscle.

Validation of a rapid and sensitive routine method for determination of chloramphenicol in honey by LC–MS/MS

Abstract: Chloramphenicol (CAP) is a broad spectrum antibiotic used in the treatment of human and animal diseases. However, CAP can exhibit toxic effects in certain susceptible individuals, causing bone marrow depression, including fatal aplastic anemia. As this condition is dose-independent, CAP has been banned for use in food-producing animals, including honeybees. In this study, a quick, simple and low-cost routine analytical method was developed for the screening and confirmation of chloramphenicol in honey by LC–MS/MS. Sample clean-up takes only two steps without SPE procedure and with recoveries >97%. Honey samples were selected from several producers in Brazil and diluted in a small amount of water. After fortification and addition of d s-chloramphenicol as internal standard, the samples were extracted with ethyl acetate. Complete validation of the method was performed on the basis of EU decision 2002/657. Within-laboratory CV reproducibility at the lowest concentration was <10%. An evaluation of two differe...

Method development for the control determination of mercury in seafood by solid-sampling thermal decomposition amalgamation atomic absorption spectrometry (TDA AAS).

Abstract: A very simple and rapid method for the determination of total mercury in fish samples using the Direct Mercury Analyser DMA-80 was developed. In this system, a previously weighted portion of fresh fish is combusted and the released mercury is selectively trapped in a gold amalgamator. Upon heating, mercury is desorbed from the amalgamator, an atomic absorption measurement is performed and the mercury concentration is calculated. Some experimental parameters have been studied and optimised. In this study the sample mass was about 100.0 mg. The relative standard deviation was lower than 8.0% for all measurements of solid samples. Two calibration curves against aqueous standard solutions were prepared through the low linear range from 2.5 to 20.0 ng of Hg, and the high linear range from 25.0 to 200.0 ng of Hg, for which a correlation coefficient better than 0.997 was achieved, as well as a normal distribution of the residuals. Mercury reference solutions were prepared in 5.0% v/v nitric acid medium. Lyophilised fish tissues were also analysed; however, the additional procedure had no advantage over the direct analysis of the fresh fish, and additionally increased the total analytical process time. A fish tissue reference material, IAEA-407, was analysed and the mercury concentration was in agreement with the certified value, according to the t-test at a 95% confidence level. The limit of quantification (LOQ), based on a mercury-free sample, was 3.0 µg kg(-1). This LOQ is in accordance with performance criteria required by the Commission Regulation No. 333/2007. Simplicity and high efficiency, without the need for any sample preparation procedure, are some of the qualities of the proposed method.

A multi-residue method for the determination of 90 pesticides in matrices with a high water content by LC-MS/MS without clean-up.

Abstract: A method using QuEChERS extraction and LC-MS/MS in electrospray positive ionisation mode was developed and validated for the analysis of 90 pesticides in a high water content matrix (tomato) in a single chromatographic run. To assess the intra-laboratory reproducibility of the method, validation was conducted on four different days by two different analysts. The validation data was treated using a spreadsheet developed in-house, which sets the most appropriate model for linear fit by determining whether the residuals of the calibration curves are homocedastic or heterocedastic. A statistical test for the significance of regression was also carried out. Calibration was always matrix-matched and the curves were obtained over the range 0.0075-0.10 or 0.020-0.125 mg kg(-1). Identification of analytes was based on retention times and MRM ratios. Recoveries were assessed at four different levels for each analyte and were between 73 and 106%, with relative standard deviations under reproducibility conditions of <20%. The measurement uncertainties of the method for each pesticide analysed were below 50%. Previous validation of the same method, applied to papaya samples and satisfactory results obtained in various proficiency tests with different high water content matrices, demonstrated the applicability of the method to these classes of commodities, without clean-up. The validated method will be applied routinely in the pesticide residues monitoring programme that constitutes the National Residue and Contaminant Control Plan of Brazil.

Caracterização das lesões por Cysticercus bovis, na inspeção post mortem de bovinos, pelos exames macroscópico, histopatológico e pela reação em cadeia da polimerase (PCR)

Abstract: Considering the importance of improving methods for diagnosis of bovine Cysticercosis, this study aimed to verify Cysticercus bovis occurrence in different anatomical sites, as head, heart, esophagus, diaphragm, tongue, liver and carcass, examined by federal inspection service. Diagnosis was performed by gross examination, histopatholgy and PCR with boiling DNA extraction for metacestode identification. Of 22043 slaughtered cattle, 713 (3.23%) were infected. The heart was mostly affected with 1.90% (420/22043), followed by head, 1.11% (245/22043), esophagus, 0.08% (18/22043), carcass, 0.07% (15/22043), diaphragm, 0.03% (7/22043), liver, 0.02% (5/22043) and tongue, 0.01% (3/22043). Of the cysts obtained, 58.35% (416/713) were dead and 41.65% (297/713) were alive. The differences among anatomical sites and cysts status were significant (p<0.05). Of the 416 dead cysts 253, characterized by nodular firm whitish lesions, containing yellowish material, some times in calcareous aspect were examined for histopathology. The histological exams of these cysts yielded granulomatous lesions, whose centers were characterized by caseous and/or calcareous material, multinucleate giant cells, histiocytes in palisade and infiltrate composed predominantly by lymphoid cells, wrapped up by fibrosis. Some times the lesions peripheries had granulation tissue and mineralized areas, like linear blade. The parasite debris were like a hyaline, non cellular material with spherical and ovoid, basophilic, eosinophilic and colorless corpuscles. These corpuscles were seen rarely, some times, among inflammatory reaction. Fibrous nodules, rich in lymphoid or mixed infiltrates, were frequently seen. Of the live cysts subjected to PCR with boiling DNA extraction, 65% (13/20) were positive for C. bovis, confirming the ambulatory diagnosis and the efficacy of the PCR procedure used. Due to microscopic and PCR diagnostic exams of C. bovis, mainly in the liver and esophagus, it is suggested changes in the 176 article of the regulatory inspection, by including these sites in the bovine routine inspection at the slaughterhouses.

The National Agricultural Laboratories of Brazil and the control of residues and contaminants in food.

Abstract: The laboratory activity of the Ministry of Agriculture, Livestock and Food Supply in Brazil has a history that is richer than most people are aware of. The institutions that today are known as National Agricultural Laboratory – Lanagros – were once a smaller initiative that suffered ups and downs throughout the decades. The recognition that the Lanagros have today – as reference centres with open communication channels with some of the world's greater laboratories in residue and contaminants in food analyses – is the fruit of several years of hard work, good ideas and a strong will never to let down society. Today the Lanagros act not only by performing analyses for the monitoring and investigation programmes, but also in the research and development of analytical methods, providing technical advice on the elaboration of guidelines and normatives, international negotiation and the evaluation of other laboratories. The Lanagros work in an ISO 17025 environment, and they are now being directed and prepared ...

Validation of a quantitative and confirmatory method for residue analysis of aminoglycoside antibiotics in poultry, bovine, equine and swine kidney through liquid chromatography-tandem mass spectrometry

Abstract: The use of aminoglycoside antibiotics in food animals is approved in Brazil Accordingly, Brazilian food safety legislation sets maximum levels for these drugs in tissues from these animals in an effort to guarantee that food safety is not compromised Aiming to monitor the levels of these drugs in tissues from food animals, the validation of a quantitative, confirmatory method for the detection of residues of 10 aminoglycosides antibiotics in poultry, swine, equine and bovine kidney, with extraction using a solid phase and detection and quantification by LC-MS/MS was performed The procedure is an adaptation of the US Department of Agriculture, Food Safety and Inspection Service (USDA-FSIS) qualitative method, with the inclusion of additional clean-up and quantification at lower levels, which proved more efficient Extraction was performed using a phosphate buffer containing trifluoroacetic acid followed by neutralization, purification on a cationic exchange SPE cartridge, with elution with methanol/acetic acid, evaporation, and dilution in ion-pair solvent The method was validated according to the criteria and requirements of the European Commission Decision 2002/657/EC, showing selectivity with no matrix interference Linearity was established for all analytes using the method of weighted minimum squares CCα and CCβ varied between 1036 and 12,293 µg kg(-1), and between 1073 and 14,588 µg kg(-1), respectively The limits of quantification varied between 27 and 688 µg kg(-1) The values of recovery for all analytes in poultry kidney, fortified in the range of 500-1500 µg kg(-1), were higher than 90%, and the relative standard deviations were lower than 15%, except spectinomycin (218%) Uncertainty was estimated using a simplified methodology of 'bottom-up' and 'top-down' strategies The results showed that this method is effective for the quantification and confirmation of aminoglycoside residues and could be used by the Brazilian programme of residue control

Two Arabidopsis thaliana dihydrodipicolinate synthases, DHDPS1 and DHDPS2, are unequally redundant

Abstract: In Arabidopsis thalinana (L.) Heynh., DHDPS1 and DHDPS2 encode orthologous dihydrodipicolinate synthases (DHDPS), the first enzyme of the lysine (Lys) biosynthesis pathway. A TDNA insertion mutant of dhdps2 was previously reported to be viable and to accumulate free threonine (Thr). Analysis of additional TDNA insertion lines showedthatdhdps1anddhdps2mutantsarebothviableandthatwhereasdhdps2mutantsaccumulateThr,dhdps1plantsdo not. Thr-accumulation was complemented by heterologous expression of Escherichia coli DapA, indicating that the phenotype is due to reduced DHDPS activity in dhdps2. DHDPS1 contributes ~30% towards the total DHDPS activity in leaves of youngplants andDHDPS2contributes 70%; therefore, thethreshold of activity resulting inThr accumulation lies within this narrow range. dhdps1-dhdps2 double mutants could not be isolated, even after exogenous feeding with Lys. SegregationanalysisindicatedthatgameteslackingfunctionalDHDPSgenesaredefective,asareembryos.Plantscarrying only a single DHDPS2 gene do not accumulate Thr, but they show a gametophytic defect that is partially rescued by Lys application. Despite the accumulation of Thr, dhdps2 seedlings are no more sensitive than wild-type plants to growth inhibition by Lys or the Lys precursor diaminopimelate. They also are not rescued by methionine at growth-inhibitory Lys concentrations. Exogenous application of Lys and methionine to dhdps2 mutants did not reduce the accumulation of Thr.

Method validation for the determination of total mercury in fish muscle by cold vapour atomic absorption spectrometry.

Abstract: A method was validated for the determination of total Hg in fish muscle using continuous flow cold vapour atomic absorption (CVAAS) after microwave digestion in closed vessels. The method was validated according to European Union Regulations 333/2007 and 657/2002, considering the maximum level for the metal in fish, established by European Union regulation 1881/2006. The procedure for determining linear range, selectivity, recovery, precision, trueness, decision limit (CCα), detection capability (CCβ), measurement uncertainty and robustness of the method is reported. The results of the validation process demonstrate the method fulfils the provisions of the Commission Regulation. The selectivity study indicated that there was no matrix effect on the calibration curve between the concentration range of 1.0 and 30.0 µg Hg l(-1). The mean recovery calculated at six levels of fortification was in the range of 94-104%. The limit of detection (LOD) and limit of quantification (LOQ) values were 4.90 and 15.7 µg kg(-1), while the CCα and CCβ values were 0.517 and 0.533 mg kg(-1), respectively, for the maximum contaminant level of 0.500 mg kg(-1). The relative expanded measurement uncertainty of the method was 0.055 mg kg(-1). The method was not affected by slight variations of some critical factors (ruggedness minor changes) as sample mass and volume of the HNO(3) and H(2)O(2) used in the digestion step. The method allowed accurate confirmation analyses of the CRM DORM 3. In fact, the Z-scores attained in a proficiency test round were well below the reference value of 2.0, proving the excellent performance of the laboratory.

Risk-Off Method: Improving Data Quality Generated by Chemical Risk Analysis of Milk

Abstract: Here the Risk-Off Method is presented as a contribution to improve the quality of data and information using milk chemical safety as a model, as overseen by the National Plan for Control of Residues and Contaminants (PNCRC) of the Brazilian Ministry of Agriculture, Livestock and Supply (MAPA). In particular, Small and Medium Enterprises (SMEs), which notably lack internal expertise, could benefit from the Risk-Off method, given that SMEs worldwide contribute significant amounts of food to meet global needs. This study develops an innovative tool to help countries provide robust and transparent chemical safety guarantees for their food products. Creating a flexible base platform to appropriately pre-classify results generated by laboratory testing of food samples, the method pre-processes data undergoing the process of Knowledge Discovery in Databases – KDD, producing systemic intelligence deriving from effective, proactive assessment and management of chemical safety risks in foods, a complex issue of increasingly global concern.

Bioactivity-based screening methods for antibiotics residues: a comparative study of commercial and in-house developed kits.

Abstract: Two bioactivity-based screening methods for antibiotic residue analysis (FAST Antimicrobial Screening Test and PremiTest) were compared, in terms of sensitivity, with a new in-house developed tube test assay using Escherichia coli. Tests were performed using antibiotic standards, spiked samples and real incurred samples. The minimum inhibitory concentration (MIC) for several antibiotics was established and compared with maximum residue levels (MRLs) in samples. The results of all evaluated tests are compared with liquid chromatography-tandem mass spectrometry multi-residue screening tests to compare parameters such as sample preparation, cost, time of analysis and confidence in results. For all tests, values of half the maximum residue limit (0.5 × MRL) were considered as a satisfactory target for a screening method. The potential and limitations of each method are discussed to indicate more rational and effective strategies for high-throughput residue monitoring and surveillance programmes. It was concluded that bioactivity-based screening methods are a useful tool, but the best compromise between minimum performance limits, cost and selectivity must be taken into account. For laboratories equipped with mass spectrometry, multi-class screening methods provide more specific responses with high sensitivity.

A multi-residue method for the determination of pesticides in high water content matrices by gas chromatography–single quadrupole mass spectrometry with electron ionisation (EI-GC/MS)

Abstract: An EI-GC/MS method for the determination of pesticide residues in vegetable matrices with high water content was validated using papaya samples. The validation of a multi-residue pesticide method was in agreement with national and international regulations enabling the Ministry of the Agriculture, Livestock and Food Supply of Brazil to cover a large number of matrices and pesticide residues in its monitoring and control programmes. The extraction used 60 mL of ethyl acetate and 30 g of sample previously processed. After extraction, clean-up of all the extracts was carried out by percolation through GBC cartridges. The samples were then injected in an EI-GC/MS system. Calibration curves were prepared in quadruplet by fortifying blank extracts with a standard solution containing all the pesticides studied at 0.000, 0.005, 0.010, 0.020, 0.030, 0.050, 0.080 and 0.100 mg kg(-1). For the recovery study, blank samples were fortified at 0.010, 0.020, 0.030, 0.050 and 0.080 mg kg(-1) and then submitted to the extraction procedure. The complete procedure was repeated over four different days by two analysts. The regression parameters of calibration curves were calculated for each validation day. Linearity, selectivity, specificity, robustness, limits of detection and quantification were also assessed. The uncertainty was estimated for each analyte at each spike level studied. The method had recoveries between 91% and 105% and precision results ≤ 20%. Limits of quantification were below or equal to the maximum residue limits (MRLs) regulated by Brazilian legislation. The MRLs of the selected pesticides are not regulated by CODEX Alimentarius. The results are also in agreement with SANCO/10684/2009.

Evolution of a residue laboratory network and the management tools for monitoring its performance

Abstract: Since 2005 the National Residue & Contaminants Control Plan (NRCCP) in Brazil has been considerably enhanced, increasing the number of samples, substances and species monitored, and also the analytical detection capability. The Brazilian laboratory network was forced to improve its quality standards in order to comply with the NRCP's own evolution. Many aspects such as the limits of quantification (LOQs), the quality management systems within the laboratories and appropriate method validation are in continuous improvement, generating new scenarios and demands. Thus, efficient management mechanisms for monitoring network performance and its adherence to the established goals and guidelines are required. Performance indicators associated to computerised information systems arise as a powerful tool to monitor the laboratories’ activity, making use of different parameters to describe this activity on a day-to-day basis. One of these parameters is related to turnaround times, and this factor is highly affected...

Single laboratory validation of a SPE method for the determination of PAHs in edible oils by GC-MS

Abstract: This article describes a method for the quantification of seven Polycyclic Aromatic Hydrocarbons (PAHs) in edible oils (soy, sunflower and olive). It involved the application of a low-volume liquid–liquid extraction (LLE) technique followed by a solid-phase extraction (SPE) clean-up with C18 and silica cartridges. Separation and analysis of compounds were performed by gas chromatography coupled to mass spectrometry (GC-MS). 13C-labeled PAHs as internal standards were used to aid the identification of compounds and to determine the efficiency of the extraction method in an isotope dilution mass spectrometry (IDMS) approach. Low-volume LLE and SPE clean-up procedures allowed the reduction of solvent consumption, eliminated the necessity of a previous saponification step and provided less sample preparation time when compared to traditional PAHs extraction and clean-up methods. The analytical procedure was validated according to recommendations of the European Commission Decision 2002/657/EC and European Commission Regulations (2007/333/EC and 2011/836/EU). Acceptable values (except for chrysene) were obtained for the following parameters: linearity (r2 > 0.98), limit of quantification (0.12 < LOQ < 0.68 μg kg−1), limit of detection (0.04 < LOD < 0.23 μg kg−1), trueness (recovery rates and certified reference material normalized error), and precision (repeatability and intermediate precision). Recoveries higher than 80% were attained for seven PAHs, at three concentration levels (0.75, 2.00 and 4.00 μg kg−1). This validated method will be used by the Ministry of Agriculture, Livestock and Food Supply in Brazil.

Evolution, importance and evaluation of cultivar protection in Brazil: the work of the SNPC

Abstract: Law no. 9.456/97 instituted the Plant Variety Protection Act (Lei de Protecao de Cultivares - LPC) in Brazil, bearing a range of positive aspects for Brazilian agriculture, such as the increase in the number of new varieties in Brazil, both domestic and foreign; incentives for breeding activities in the country; and socioeconomic benefits to the agricultural sector. In 15 years of activity in the sphere of the Ministry of Agriculture, Livestock and Food Supply (Ministerio da Agricultura, Pecuaria e Abastecimento), the National Plant Variety Protection Service (Servico Nacional de Protecao de Cultivares - SNPC) has consolidated its activity, not only through its credibility in analysis and granting of plant variety protection (PVP) applications, but also through its proactive stance in technical and legal activities in Brazilian and international affairs, as well as involving the scientific community in a participatory manner in the actions it develops. Nevertheless, in spite of these advances, there is a great deal of discussion regarding the limitations to effective exercise of plant breeders' rights caused by some legal provisions of the LPC that may lack refinement.