GB Food Contact Materials Testing: A Technical Guide to China National Standard (GB 4806) Compliance

GB food contact materials testing evaluates materials and articles intended for food contact against China's mandatory national food safety standards (GB standards), including the GB 4806 series, GB 9685, and GB 31604 test methods. This guide explains the regulatory framework, sample categories, testing items, migration test methods, and typical applications for manufacturers, importers, and exporters seeking compliance in the Chinese market. All testing described here can be performed by accredited third-party laboratories.

Technical Overview

GB food contact materials testing refers to the conformity assessment of materials, articles, coatings, and components that are intended to come into contact with food, evaluated against the mandatory national food safety standards of China (GB standards). The regulatory basis is the Food Safety Law of the People's Republic of China, which requires that all food contact materials and products sold or imported into China must comply with the applicable GB standards. The system is administered by the National Health Commission (NHC) together with the State Administration for Market Regulation (SAMR), and market surveillance testing is routinely conducted on both domestic and imported goods.

The core of the framework is a risk-based, migration-oriented assessment model. Rather than examining the raw material composition alone, GB testing measures how much of a substance can transfer from the material into food under worst-case foreseeable conditions of use. The principal standard families include:

• GB 4806.1-2016 — General safety requirements for food contact materials and products, covering labeling, declarations of compliance, and general principles.
• GB 4806.2-2015 — Silicone and rubber nipples and teats for infant feeding.
• GB 4806.3-2016 — Enamel materials and articles.
• GB 4806.4-2016 — Ceramic materials and articles.
• GB 4806.5-2016 — Glass materials and articles.
• GB 4806.6-2016 — Plastic resins, including the positive list of permitted resins in its annex.
• GB 4806.7-2016 — Plastic materials and articles, revised as GB 4806.7-2023 with an expanded positive list.
• GB 4806.8-2016 — Paper and paperboard materials and articles.
• GB 4806.9-2016 — Metal materials and articles, revised as GB 4806.9-2023.
• GB 4806.10-2016 — Coatings and coated articles.
• GB 4806.11-2016 — Rubber materials and articles.
• GB 9685-2016 — Standard for the use of additives in food contact materials, containing the positive list of permitted additives with specific migration limits (SML) and maximum use levels.
• GB 31603-2015 — Good manufacturing practice (GMP) for food contact materials and products.
• GB 31604 series — Analytical test methods for food contact materials, including GB 31604.1-2015 general rules for migration testing.
• GB 5009.156-2016 — General rules for the pretreatment of samples in migration tests.

Because several parts of the series have been revised in recent years, manufacturers should always confirm the latest effective edition of each standard before commissioning testing at accredited third-party laboratories.

Testing Samples

GB food contact materials testing covers virtually every category of material that may touch food during production, processing, packaging, storage, preparation, or consumption. The applicable test program depends on the material type, the intended food type, and the expected temperature and duration of contact.

Plastic and Polymeric Materials

This is the largest sample category and includes plastic resins, films, bags, bottles, containers, lids, trays, disposable tableware, cutting boards, straws, and plastic components of kitchen appliances. Plastic articles are tested against GB 4806.7, while the base resins must first conform to GB 4806.6 and its positive list. Common polymer types include polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polystyrene (PS), polyvinyl chloride (PVC), polycarbonate (PC), polyamide (nylon, PA), and melamine-formaldehyde resins.

Paper and Paperboard

Samples include paper cups, paper containers, paper bags, wrapping paper, cartons, and molded pulp trays intended for direct food contact. Testing under GB 4806.8 addresses total migration, heavy metals, and fluorescent whitening agents, and items with plastic or aluminum coatings may additionally require evaluation of the coating layer.

Metals and Alloys

Samples include stainless steel cutlery and cookware, aluminum foil and containers, food cans, knives, pots, kettles, and metal parts of food processing equipment. GB 4806.9 focuses on the migration of metallic elements such as arsenic, cadmium, lead, chromium, and nickel into acidic food simulants, with additional attention to coated or plated surfaces.

Glass, Ceramics, and Enamel

Samples include ceramic tableware, glass jars and bottles, glass cookware, and enamel-coated pots. For these materials, the key hazard is the release of lead and cadmium from glazes, decorations, and pigments, determined by extraction with 4% acetic acid in accordance with GB 4806.4, GB 4806.5, and GB 4806.3. Limits are differentiated by article shape, for example flatware versus hollowware, in a manner broadly consistent with ISO 6486.

Rubber and Silicone Elastomers

Samples include jar seals and gaskets, dispenser hoses, conveyor belts, oven gloves, baking mats, and infant feeding teats. Rubber articles are tested under GB 4806.11, while infant teats and pacifiers are additionally governed by GB 4806.2. Key parameters include N-nitrosamines and N-nitrosatable substances, volatile substances, formaldehyde, and primary aromatic amines.

Coatings and Coated Articles

Samples include interior coatings of food and beverage cans, epoxy lacquers, non-stick fluoropolymer coatings on cookware, and anti-corrosion coatings on metal packaging. GB 4806.10 evaluates overall migration and the specific migration of monomers and starting substances, and any coating additive must appear in the GB 9685 positive list.

Testing Items

The specific test parameters are determined by the material standard applicable to the sample, the composition declared by the manufacturer, and the positive-list restrictions in GB 9685. The main categories of testing items are:

• Overall migration (total migration): the total mass of non-volatile substances transferred into food simulants, expressed in mg/dm2, with a general limit of 10 mg/dm2 for plastic, coating, rubber, and paper materials.
• Heavy metals migration: determination of lead, cadmium, arsenic, chromium, nickel, and other elements in food simulants, typically using 4% acetic acid as the extracting medium.
• Specific migration of monomers and starting substances: for example, melamine (SML 2.5 mg/kg), bisphenol A (SML 0.6 mg/kg), formaldehyde (SML 15 mg/kg), styrene, acrylonitrile, vinyl chloride monomer, caprolactam, terephthalic acid, and primary aromatic amines (sum limited to 0.01 mg/kg).
• Specific migration of additives: any additive used in the material must be listed in GB 9685 and comply with its SML or maximum residue limits.
• Potassium permanganate consumption: an indicator of oxidizable extractable substances, historically applied to plastics and coatings in contact with aqueous foods.
• Heavy metals content (as lead): a screening parameter for pigments and inorganic additives in several material standards.
• Decolorization test: verification that colorants do not bleed onto cotton pads moistened with water, food oil, or ethanol-based solvents.
• Fluorescent whitening agents: restricted for paper and paperboard intended for food contact.
• N-nitrosamines and N-nitrosatable substances: required for rubber and silicone infant teats and pacifiers.
• Lead and cadmium release: the defining parameter for ceramics, glass, and enamel, with category-specific limits.
• Sensory requirements: the material must not release substances that impart objectionable color, odor, or taste to food.
• Residual reactants and impurities: such as residual solvents in coatings and residual monomers quantified on the material itself rather than in migration solution.

Testing Methods

GB migration testing follows the general rules of GB 31604.1-2015 and the pretreatment procedures of GB 5009.156-2016, with individual analytical methods specified in the GB 31604 series. The methodology is broadly harmonized with the logic of EN and ISO food contact test standards, which facilitates multi-market test programs.

Selection of Food Simulants

Food simulants are assigned according to the type of food the article will contact:

• Aqueous foods (non-acidic): 10% ethanol aqueous solution.
• Acidic foods: 4% acetic acid aqueous solution.
• Alcoholic foods: ethanol-water mixtures matching the alcohol content of the food, commonly 20% or 50% ethanol.
• Fatty foods: vegetable oil, or substitute simulants such as 95% ethanol and isooctane applied with appropriate reduction factors.

Selection of Test Conditions

Time-temperature conditions are chosen to reflect the most severe foreseeable use of the article. Typical migration conditions include 40 °C for 24 hours for long-term room-temperature storage, 70 °C for 2 hours for hot filling, and 100 °C for 1 hour for boiling-water contact, with higher-temperature or longer conditions applied where the intended use justifies them. The exposure geometry also matters: containers are filled with simulant, while flat articles are immersed using a defined surface-area-to-volume ratio so that results can be converted to mg/dm2 or mg/kg.

Analytical Techniques

Depending on the parameter, accredited third-party laboratories apply the following instrument methods in accordance with the relevant GB 31604 method standard:

• Gravimetric analysis for overall migration determination.
• Inductively coupled plasma mass spectrometry (ICP-MS), ICP optical emission spectrometry (ICP-OES), and atomic absorption spectroscopy (AAS) for elemental migration.
• Gas chromatography with mass spectrometry (GC-MS) and headspace GC-MS for volatile monomers such as vinyl chloride, styrene, and residual solvents.
• High-performance liquid chromatography (HPLC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) for melamine, bisphenol A, caprolactam, primary aromatic amines, and additive migration.
• UV-visible spectrophotometry for formaldehyde and potassium permanganate consumption.
• Visual and instrumental assessment for decolorization, fluorescent whitening agents, and sensory properties.

Test reports should clearly state the standard applied, the food simulants and conditions used, the analytical limits of detection and quantification, and a pass or fail conclusion against each regulatory limit. These reports, together with a declaration of compliance, form the core technical dossier required for market access, customs clearance, and regulatory inspection in China.

Applications

GB food contact materials testing serves a wide range of commercial and regulatory purposes:

• China market access for domestically manufactured food contact products, supporting compliance with mandatory national standards before sale.
• Import compliance, since food contact articles imported into China must meet the same GB requirements and are subject to port inspection.
• Supplier qualification and incoming material control for food and beverage brands, packaging converters, and kitchenware retailers.
• Quality control during product development, resin selection, coating formulation, and colorant approval.
• Baby and infant product compliance, where nipples, bottles, and feeding utensils attract heightened regulatory scrutiny and stricter limits.
• Food processing equipment evaluation, including seals, gaskets, hoses, tanks, and machinery parts that contact food during production.
• E-commerce platform documentation, as major online sales channels increasingly request GB test reports from sellers.
• Market surveillance response, root cause investigation, and remediation for products flagged in official sampling programs.
• Combined multi-market test programs, where GB testing is performed in parallel with EN-based and other national frameworks to support global export strategies.

FAQ

What is the difference between GB 4806.6 and GB 4806.7?

GB 4806.6 applies to plastic resins as raw materials and includes the positive list of permitted resins, whereas GB 4806.7 applies to finished plastic materials and articles. A compliant plastic article requires both a compliant resin basis and conformity of the finished product to GB 4806.7, including overall migration, specific migration limits, and sensory requirements.

Is GB food contact testing mandatory for imported products?

Yes. The Food Safety Law of the People's Republic of China applies equally to imported food contact materials, and importers must demonstrate conformity with the applicable GB standards. Test reports from accredited third-party laboratories are customarily required during customs clearance and market surveillance.

What is the overall migration limit under GB standards?

For plastic, coating, rubber, and paper food contact materials, the general overall migration limit is 10 mg/dm2 of contact surface. Compliance is demonstrated by gravimetric determination after exposure to the selected food simulants under the prescribed time and temperature conditions.

How are food simulants and test conditions selected?

Simulants are matched to the food type the article will contact in actual use: 10% ethanol for aqueous foods, 4% acetic acid for acidic foods, 20% or 50% ethanol for alcoholic foods, and vegetable oil or substitute solvents for fatty foods. Test conditions reflect the worst-case foreseeable use, for example 40 °C for 24 hours, 70 °C for 2 hours, or 100 °C for 1 hour, as defined in GB 31604.1 and GB 5009.156.

Which special tests apply to infant teats and pacifiers?

Silicone and rubber nipples are tested under GB 4806.2, which requires evaluation of N-nitrosamines and N-nitrosatable substances, volatile matter, migration of specific elements such as zinc, and overall migration, in addition to the general requirements of GB 4806.1.

How many samples are needed and how long does testing take?

Sample requirements depend on the number of simulants and parameters requested, and laboratories typically ask for several finished products or a defined quantity of material per test condition. Standard turnaround for a routine GB package is commonly within two to four weeks, while comprehensive positive-list screening programs may take longer.

Do GB standards replace the need for testing against other national frameworks?

No. GB compliance is specific to the Chinese market. Manufacturers exporting globally should run parallel assessments against the frameworks relevant to each destination market, and many accredited third-party laboratories design consolidated test plans to cover multiple jurisdictions efficiently.