Codex CXC 81-2022 — Code of Practice for Cadmium in Cocoa Beans
Summary
Codex CXC 81-2022 is the international Codex Alimentarius Code of Practice for the prevention and reduction of cadmium contamination in cocoa beans, adopted by the Codex Alimentarius Commission in 2022 and published by FAO and WHO in 2023. The Code of Practice (CoP) is non-binding guidance to countries and to the cocoa production industry covering the full pre-harvest, harvest, post-harvest, and transport chain, structured around recommended practices at each stage. It is the first commodity-specific Codex CoP for cadmium and is the precedent document for the broader cadmium CoP work initiated at CCCF17 in 2024 (which is extending the CXC 81-2022 model to additional commodities including rice, cereals, vegetables, fish, and seafood).
The CoP is structured in four sections. Section 4.1 covers practices before planting on new plantations (soil analysis, cover crops, plantation siting). Section 4.2 covers from-production-to-harvest practices, including soil characterization (4.2.1), strategies to immobilize cadmium in soil (4.2.2), and avoiding further contamination of the soil (4.2.3). Section 4.3 covers post-harvest practices (fermentation, drying, storage). Section 4.4 covers transport.
Provenance
Required citation per the document: “FAO and WHO. 2023. Code of practice for the prevention and reduction of cadmium contamination in cocoa beans. Codex Alimentarius Code of Practice No. CXC 81-2022. Codex Alimentarius Commission. Rome. https://doi.org/10.4060/cc5333en”
License: CC BY-NC-SA 3.0 IGO. ISBN 978-92-5-137812-0 (FAO). Adopted 2022; published Rome 2023.
Retrieved as PDF from FAO’s Codex Standards web service via WebFetch on 2026-05-03; SHA-256 of the canonical FAO PDF is pending future ingestion when the document is added to raw/standards/. The agency-website reference and the document’s CC license are sufficient primary-source citations for the values recorded here.
Scope (Section 2)
The CoP provides guidance on recommended practices to prevent and reduce cadmium contamination in cocoa beans before planting (for new plantations) and during production through harvest and post-harvest phases. It is matrix-specific to cocoa beans (the seed of Theobroma cacao L.) and is silent on other cadmium-relevant commodities; the broader Codex cadmium CoP under development at CCCF17/CCCF18 will extend coverage to additional commodities (CCCF17 2024).
Background on cadmium uptake (Section 1, Introduction)
Estimated cadmium half-life in soils ranges from 15 to 1,100 years, making prevention upstream of remediation operationally critical. Cadmium most commonly exists in the +2 oxidation state and associates in soils with iron, zinc, lead, phosphorus, magnesium, calcium, and copper. Soil cadmium concentrations and bioavailability depend mainly on soil pH (cadmium is more bioavailable at acidic pH), texture, organic material content, iron and manganese oxides and hydroxides, zinc concentration, carbonates, chlorinity, and cation exchange capacity.
A counter-intuitive interaction noted in the CoP: at alkaline pH (pH > 7.0), elevated chloride content in soils enhances chloride complex formation, which decreases cadmium adsorption on soil particles and thereby increases cadmium mobility and bioavailability. The CoP therefore recommends measuring electrical conductivity of soil and water in cocoa-growing areas where cocoa beans show relatively higher cadmium levels, with the target value at less than 2 mS/cm.
Key recommended practices
Before planting — new plantations (Section 4.1)
| Practice | Specifics |
|---|---|
| Soil analysis before planting | Required parameters include sand %, clay %, silt %, textural class, pH, organic matter %, total N %, available ppm of P, K, Pb, Fe oxides and hydroxides, Mn carbonates, Cd, Zn; changeable Ca, Mg, K, Na, Al, H (cmol(+)/kg); CEC; base saturation %; aluminum saturation %. Soil pH is the most important parameter to measure on an ongoing basis. |
| Soil sampling protocol | At least 20 subsamples per hectare per composite sample. Sampling depth 0–15 cm (because litterfall can add Cd to the top 0–5 cm). |
| Cover crops | Use perennial-legume cover crops to improve soil organic matter, reduce erosion, and reduce metal bioavailability. |
| Irrigation water monitoring | Compare against the WHO drinking-water Cd guideline of 0.005 mg/L as one possible reference. |
| Plantation siting | Site away from roads (vehicle-emission Cd), dumpsites, mining areas, smelting areas, industrial wastes, sewage discharge, household wastewater. Avoid flooded soils where the water source is Cd-contaminated. |
| Long-term cultivar selection | Plant cocoa varieties less prone to cadmium uptake. |
| Source-directed measures | Reference CXC 49-2001 (Source Directed Measures Code of Practice). |
From production to harvesting (Section 4.2)
The CoP distinguishes immobilization-of-Cd-in-soil practices (4.2.2) from avoid-further-contamination practices (4.2.3).
| Practice | Specifics |
|---|---|
| Soil characterization for existing plantations | Use accredited laboratories with validated methods, certified reference materials, and internationally-recognized methods to support cocoa exporters. |
| Phosphate fertilizer Cd control | Verify Cd content of fertilizers before use. Phosphate fertilizers and sedimentary phosphorous rock may contain high Cd; should comply with national/regional Cd limits. National criteria may set Cd:P or Cd:P₂O₅ ratios. |
| Apatite / rock phosphate | Should be avoided where possible because it can contain Cd. |
| Zinc supplementation | Cd competes with Zn for plant uptake. Apply zinc sulphate (ZnSO₄) as fertilization where soil Zn is deficient. Caution: high rates (e.g., 25 kg Zn/ha) can acidify soil and require limestone counter-treatment. |
| Liming | The most effective method to date for decreasing Cd bioavailability when soil pH is below six. Apply lime in low doses (3 t/ha/year), preferably as dolomite CaMg(CO₃)₂. Target soil pH > 6; higher pH may be needed where soil Cd is high. Avoid over-liming (reduces micronutrient bioavailability). Verify added lime does not contain Cd. |
| Organic amendments | Treated manure from stabled livestock or compost increases organic matter and microbiological activity, raising Cd adsorption. |
| Biochar | Reduces Cd uptake in cocoa beans at rates comparable to liming; can be additive to liming. |
| Vinasse (sugarcane alcohol distillate) | Source of K; promotes mycorrhizal-fungus installation in cocoa roots, improving phosphorus nutrition and immobilizing Cd. |
| Soil amendments — full list | Magnesium sulphate, vinasse, zeolite (sand-content soils, clay-textured soils), humus, charcoal/biochar, calcium sulphate (CaSO₄), cane by-product (bagasse), zinc sulphate (ZnSO₄), dolomite (CaMg(CO₃)₂), vermicompost, sugar cane, palm kernel cake, phosphate rock (only if Cd-low), compost. |
| Genotype / grafting | Cocoa plant genotypes with low Cd bioaccumulation can be used in breeding and as rootstocks for grafting; experimental but viable across various soil types and Cd levels. |
| Litterfall management | Remove pruned cocoa and shade-tree limbs and leaves from the ground (they can contain Cd that decomposes into the topsoil), particularly in orchards with high foliar Cd. |
| Avoid | Sewage sludge; burial or incineration of household waste; nearby industrial activities (non-ferrous mining and smelting, metal-using industries, leather tanning, coal combustion, phosphate fertilizer manufacturing). |
Post-harvest phase (Section 4.3)
| Practice | Specifics |
|---|---|
| Mucilage draining during fermentation | Mucilage draining for 12, 24, or 36 hours reduces cadmium concentrations without affecting organoleptic quality. Improves sensorial quality by reducing acidity. |
| Yeast inoculation during fermentation | Saccharomyces cerevisiae absorbs Cd during cocoa fermentation; experimental studies show that increasing S. cerevisiae concentration during fermentation can reduce Cd content in beans. |
| Fermentation environment | Ensure beans are not contaminated by smoke, dryer or vehicle exhaust gases, or industrial discharges during fermentation. |
| Drying surface | After fermentation, dry beans on clean solid surfaces to avoid soil contamination. Target moisture content: less than 8 percent for storage stability. |
| Storage | Prevent contamination from spilled fuels, exhaust gases, fumes. |
Transport phase (Section 4.4)
The CoP specifies eight transport-stage practices: cover loading and unloading areas to protect from rain; well-maintained and thoroughly cleaned vehicles; clean, undamaged tarpaulins and covers; containers not previously used for chemicals or noxious substances; low humidity via ventilated containers and cardboard or kraft-paper lining; bagged-cocoa loading with absorbent covers for condensation; bulk-cocoa sealable plastic liner kept clear of container roof; unobstructed ventilation holes; minimal temperature fluctuation and isolation from noxious materials.
Definitions (Section 3, selected)
| Term | Definition (paraphrased from CoP) |
|---|---|
| Adsorption | Physical or chemical attraction and retention of Cd to soil particles. |
| Absorption | Net uptake of Cd from soil by cocoa-tree roots. |
| Bioavailability | Accessibility to normal metabolic and physiological processes; influenced by total concentration, speciation, redox potential, temperature, total organic content, suspended particulate content. |
| Biochar (biocarbon) | By-product of pyrolysis of residual biomass; stable carbonate derivative produced from plant or animal biomass for agricultural application. |
| Cation exchange capacity (CEC) | Soil’s ability to hold positively charged ions; clay-mineral and organic-matter components have negatively charged surface sites that adsorb cations. |
| Cocoa bean | Seed of the cocoa fruit, composed of episperm (also called integument, testa, or shell), embryo, and cotyledon. |
| Drying | Reduction of cocoa-bean moisture to less than eight percent for storage stability, by sunlight or mechanical/solar dryers. |
| Fermentation | Process designed to degrade pulp or mucilage and initiate biochemical changes in the cotyledon by enzymes and farm-environment microorganisms. |
| Shading | Cocoa cultivation under shade trees; typically about 50 percent during the first four years, reducible to 25 or 30 percent thereafter. |
| Soil amendments | Materials added to improve soil physical and chemical properties: compost, livestock manure, magnesium sulphate, vinasse, zeolite, charcoal/biochar, calcium sulphate, lime/dolomite, cane by-product (bagasse), zinc sulphate, vermicompost, sugar cane, palm kernel cake, phosphate rock, other organic matter. |
| Vinasse | By-product of sugar-cane alcohol production; main organic residue from molasses fermentation and distillation. |
Implications
- Certification: CXC 81-2022 is the foundational Codex document for any HMT&C cocoa-cadmium standard. The CoP’s practice-based recommendations (soil analysis protocol, lime dosing, mucilage draining duration, Saccharomyces cerevisiae inoculation, plantation siting away from industrial sources) are the auditable interventions a certifier can require of producers seeking certification. HMT&C cocoa thresholds set tighter than the Codex MLs in CXS 193-1995 should reference this CoP for the implementation pathway.
- Courses: the CoP’s four-stage structure (before-planting, production-to-harvest, post-harvest, transport) is a curriculum-ready spine for cocoa supply-chain mitigation training. Each section is self-contained and audit-ready.
- App: the CoP does not contain finished-product cocoa cadmium concentration values; it is a process document, not an occurrence document. App-layer cocoa cadmium values come from CXS 193-1995 (matrix MLs) and from JECFA 91st 2022 (population exposure assessment), not from this CoP.
- Mitigation: this is the load-bearing source for agronomic, processing, and parts of formulation cocoa-cadmium mitigation content. The four mitigation strategy pages cite this CoP for the cocoa-specific intervention specifics.