Ministry of Agriculture Agricultural Residue Standards Pesticide Residues
buyMinistry of AgriculturePesticide residue standardsJust go to the national standard product network, and the national standard product network sells solution pesticide standards for the first-level agent of the Ministry of Agriculture's agricultural residue standards. The following is the Ministry of Agriculture's pesticide residue detection method
Announcement No. 2386 of the Ministry of Agriculture
Announcement No. 2386 of the Ministry of Agriculture
In order to uniformly standardize the formulation and revision of standards for pesticide residue detection methods, our Ministry has organized and formulated the "Guidelines for the Preparation of National Standards for Pesticide Residue Detection Methods", which have been considered and adopted at the 12th meeting of the First National Pesticide Residue Standards Review Committee and are hereby promulgated for implementation.
Ministry of Agriculture
April 11, 2016
Guidelines for the development of national standards for pesticide residue detection methods
I. Overview
In order to ensure the scientificity, advancement and applicability of the standards for pesticide residue detection methods, refer to GB/T 1.1-2009 "Guidelines for Standardization Work, Part 1: Structure and Preparation of Standards", GB/T 20001.4-2001 "Rules for the Preparation of Standards, Part 4: Chemical Analysis Methods", GB/T 27404-2008 "Laboratory Quality Control Specifications, Food Physical and Chemical Testing", SN/T0001-1996 "Pesticides, Veterinary Residues and Biotoxins in Exported Commodities", Basic Provisions for the Preparation of Standards ", and the relevant provisions of the Codex Alimentarius Commission (CAC) to prepare the" Guidelines for the Preparation of National Standards for Pesticide Residue Testing Methods ", which serve as the technical basis for the preparation of standards for pesticide residue testing methods.
Scope of application
This guide is applicable to the preparation of national food safety standards for the detection of pesticide residues in plant-derived foods. For the preparation of standards for the detection of pesticide residues in other agricultural products, livestock products, aquatic products and foods, please refer to this guide.
In this guide, plant-derived foods refer to the agricultural products corresponding to the crops listed in the "Classification of Crops Used for the Establishment of Maximum Residue Limits for Pesticides" (Ministry of Agriculture Announcement No. 1490).
III. Basic requirements
1 Comply with the requirements of GB/T 1.1-2009 and GB/T 20001.4-2001.
2. The text expression structure is rigorous, the layers are clear, the words are accurate, and the expression is clear, without ambiguity. Terms and symbols are unified, and the unit of measurement is expressed in the legal unit of measurement.
The technical indicators of pesticide residue detection methods comply with the requirements of Appendix A.
IV. The structure of the standard
1. Elements of an informative overview: cover, foreword, introduction.
2. Normative general elements: standard name, warning, scope, normative reference document.
3. Normative technical elements: principles, reagents and materials, instruments and equipment, sampling, sample preparation, analytical procedures, calculation of results, precision, maps, quality assurance and control.
4. Informative Supplementary Elements: Informative Appendix.
5 Normative Supplementary Elements: Normative Appendices.
Cover, preface, standard name, scope, reagents and materials, instruments and equipment, sample preparation, analytical procedures, calculation of results, precision and atlas are essential elements, and others are optional.
V. Elements of an informative overview
1 Cover requirements
1.1 The cover is marked with the following information: standard name, English translation, logo, number, international standard classification number (ICS number), Chinese standard document classification number, release date, implementation date, release department (Ministry of Health of the People's Republic of China, Ministry of Agriculture of the People's Republic of China), etc.
1.2 If one or more standards are replaced, the cover shall be marked with the number of the replaced standard.
1.3 If an international organization standard is adopted, indicate the degree of consistency in accordance with the provisions of GB/T 20000.2.
2 Introduction
2.1 Structure description.
2.2 In lieu of an information note, identify the number and name of the standard or document being replaced, and list the main technical changes compared to the previous version.
2.3 Description of the standard relationship with international organizations or other countries, the degree of consistency with international standards is expressed in terms of equivalence (IDT), modification (MOD) and non-equivalence (NEQ); standards formed on the basis of standards in other countries indicate the relationship with corresponding standards.
2.4 Release of previous versions replacing the standard.
VI. Normative general elements
1 Standard name
1.1 Standard names are generally composed of guiding elements, main elements, and supplementary elements.
1.1.1 guiding elements are "national food safety standards".
1.1.2 the main elements are the name of the product and the test object,
1.1.3 supplementary elements are detection methods, and the names are unified as ultraviolet/visible spectrophotometry, atomic absorption spectrophotometry, gas chromatography, liquid chromatography, gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry.
Example:
- National Food Safety Standard, Determination of Carbendazim Residues in Plant Foods, Liquid Chromatography
- - The English translation is Determination of??
2 warning
2.1 Use bold to label analytical products, reagents used, or analytical procedures that pose a risk or hazard to health or the environment, and their precautions.
2.2 Hazards belonging to the general notes or from the product being analyzed are marked before the scope; hazards from special reagents or materials are marked after the name of the reagent or material; hazards inherent to the analytical step are marked at the beginning of the "Analytical Steps" chapter.
3 range
3.1 Clarify the product scope tested by this standard, the names of the pesticides tested and the detection methods. Use "This standard stipulates the amount of [pesticide name] residue [detection method] in [agricultural products]". Multi-residue testing can list the Chinese and English names of all pesticides in the form of appendices.
3.2 Clarify the applicable boundaries of the detection method. Use the expression "This standard applies to the qualitative identification/quantitative determination of [pesticide name] residues in [agricultural products]".
3.3 Indicate the quantitative limit of the test method. If it is a multi-residue test, it should be listed in Appendix C.
4 Normative reference documents
If there are normative references in the standard, list the cited documents in that chapter and introduce them with the following introductory language:
The following documents are essential to the application of this document. For dated references, only dated versions apply to this document. For undated references, the latest version (including all amendments) applies to this document.
Seven, normative technical elements
1 Principle
The basic principle, characteristics and basic steps of the detection method are indicated.
2 Reagents and materials
2.1 This chapter begins with the following introduction: "Unless otherwise stated, only reagents confirmed to meet the required levels of residue detection and water meeting GB/T 6682 level are used in the analysis".
2.2 List all reagents and materials used in the detection process and their main physical and chemical properties (concentration, density, etc.). Except for reagents and materials used multiple times, those used only in the preparation of a certain reagent should not be listed in this chapter.
2.3 Reagents and materials are arranged in the following order:
A) Products used in commercially available conditions (excluding solutions), indicating their morphology and characteristics (e.g. chemical name, molecular formula, purity, CAS number), and solid products with crystalline water are marked as crystalline water.
B) Solution or suspension (excluding standard titration solutions and standard solutions), and state its content;
NOTE: If a solution is diluted from a specific solution, it is expressed as follows:
- "Dilute V1 → V2" means to dilute a specific solution of V1 to a solution of V2;
- "V1 + V2" means adding a specific solution of volume V1 to a solvent of volume V2.
C) Standard solution and internal standard solution, explaining the preparation method.
NOTE 1: Mass concentration is expressed in g/L, or in fractional multiples, such as milligrams per liter (mg/L).
Note 2: Indicate the valid period and storage conditions.
D) indicators;
E) Auxiliary materials (e.g. desiccant, solid phase extraction column, etc.).
Example:
Unless otherwise specified, the reagents used in this method are chromatographically pure, and the water is laboratory-grade water as specified in GB/T 6682.
A) Reagents
1) Sodium chloride (NaCl);
2) acetonitrile (CH3CN);
3) Methanol (CH3OH).
B) Reagent preparation
1) Sodium chloride solution (20g/L): Weigh 20g of sodium chloride, add water to dissolve, use water bandwidth evaluation to 1000mL, shake well.
2) Methanol solution (80 + 20): Measure 80 milliliters of methanol and add 20 milliliters of water, mix well.
C) Standard
Caffeine standard (C8H10N4O2, CAS number: 58-08-2): purity ≥ 99%.
D) Standard solution preparation
1) Caffeine standard stock solution (2.0 mg/mL): accurately weigh 20.0 mg of caffeine standard in a 50 mL beaker, dissolve with methanol, and transfer to
In a 10 mL volumetric flask, use methanol for bandwidth evaluation. Store in a refrigerator at 4 ° C for half a year.
2) caffeineStandard intermediate solution (200μg/mL): Accurately absorb 5.0 mL of caffeine standard stock solution in a 50 mL volumetric bottle for bandwidth evaluation. Store in a refrigerator at 4 ° C for one month.
3 Instruments and equipment
The names of the main instruments and equipment used in the analysis process and their main technical indicators should be listed. The order of instruments and equipment is generally analytical instruments, commonly used instruments or equipment.
Note: The manufacturer or trademark of the instrument or equipment should not be specified when writing.
4 Sample preparation
Specify the laboratory sample fractionation, sample preparation process (e.g. sampling volume, grinding, drying, homogenization, etc.), sample characteristics (e.g. particle size, mass or volume, etc.), and sample storage container materials and characteristics (e.g. type, capacity, airtightness) and storage conditions. See Appendix B for sample preparation and storage.
5 Steps to Analysis
The treatment methods of different test items are different. When writing, attention should be paid to writing down each step clearly. The test steps are usually described in imperative sentences, and the relevant tests are stated in an easy-to-read form.
5.1 Extraction
The weighing of the specimen should be clearly expressed in terms of mass or volume.
The name of the extractant, the amount, the method of extraction, and the name of the collection container and the concentration conditions should be stated.
5.2 Purification
The purification materials and purification steps used should be indicated, as well as the name of the collection container, concentration conditions, bandwidth evaluation method and bandwidth evaluation volume.
5.3 Derivatization
If the method requires derivatization, the derivatization steps should be stated.
5.4 Instrument Reference Conditions
The detection technology parameters and operating conditions should be indicated.
Example 1:
Gas chromatography: information such as column specification and model, detector temperature, inlet temperature, column temperature, injection method, injection volume, gas type and purity, flow rate, etc. should be stated.
Example 2:
Gas chromatography-mass spectrometry: information such as column specification and model, inlet temperature, detector temperature, column temperature, injection mode, injection volume, gas type and purity, flow rate, ion source temperature, interface temperature, and mass spectrometry detection mode should be stated.
Example 3:
Liquid chromatography: column specification and type, column temperature, detection wavelength (UV, fluorescence), mobile phase, flow rate, injection volume and layer elution conditions should be stated.
Example 4:
Liquid chromatography-mass spectrometry: The column specification and model, mobile phase, flow rate, injection volume, layer elution conditions, ion source type, capillary voltage, capillary temperature, atomized gas flow, collision gas type, detection method and other information should be stated, and the multi-reaction monitoring conditions should be listed.
5.5 Standard working curve
The standard working curve drawing process should be specified.
5.6 Determination
The single-point calibration method should specify the injection sequence of the standard solution and the solution to be tested. The standard working curve method should specify that the response value of the component to be tested should be within the quantitative measurement range of the instrument detection. If parallel determination is required, it should be clearly specified. For mass spectrometry testing, the basis for qualitative and quantitative determination should be stated.
5.7 Blank test
Blank tests with no sample or only blank samples should be performed using the same reagents, equipment, and procedures as the sample assay.
6 Result calculation
When expressing the measurement results, it should be indicated what kind of residue is used for calculation. The amount of pesticide residue is calculated in mass fraction ω, and the value is expressed in milligrams per kilogram (mg/kg) or milligrams per liter (mg/L), and the calculation formula is written, and the format is implemented in accordance with the provisions of 8.8 in GB/T 1.1-2009. The calculation formula should be expressed in a quantity relationship, and the number should be indicated after the formula. There is a formula in the standard that should also be numbered, and the number starts from (1). The symbol of the quantity is always in italics, and the significant digits of the calculation result should be given. The calculation result is generally not less than two significant digits.
Example:
The amount of pesticide residues measured in the sample is calculated as the mass fraction ω, and the value is expressed in milligrams per kilogram (mg/kg), calculated according to formula (1).
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In the formula:
R - the mass concentration of pesticides in a standard solution, in milligrams per liter (mg/L);
The peak area of I component in the solution of Ai sample;
Asi - Pesticidesstandard solutionThe peak area of the measured i component;
V1 - Total volume of extraction solvent in milliliters (mL);
V2 - The volume of the extraction solution used for detection is aspirated in milliliters (mL);
V3 - sample solution bandwidth evaluation volume in milliliters (mL);
M - the mass of the sample in grams (g);
The calculation results retain two significant digits, and three significant digits when the result is greater than 1mg/kg.
7 precision
7.1 Under reproducibility conditions, the absolute difference between the results of two independent assays is not greater than the reproducibility limit (r), and the data on the reproducibility limit (r) are shown in Appendix E.
7.2 Under reproducibility conditions, the absolute difference between the two independent measurement results is not greater than the reproducibility limit (R), and the data for the reproducibility limit (R) are shown in Appendix F.
8 graphs
Spectrograms of standard components should be given.
Note: The chromatographic peaks are arranged in Arabic numerals, and the components represented by each Arabic numeral are indicated at the bottom of the figure, and the mass concentration of the standard solution should be marked.
9 others
In addition to the above technical content, other technical content and key technologies can be reasonably written according to the characteristics and needs of the testing method, such as descriptions of special circumstances, test reports, and relevant diagrams.
VIII. Information Appendix
Provide additional information to assist in the understanding or use of the standard as an informative appendix.
IX. Normative Appendices
When the content that a part of a standard should implement is placed in the body of the standard to affect the standard structure, this part can be placed at the back of the body as a normative appendix.
