Fertilisers and cadmium in cacao: Risks and recommendations

• Soils contain much more cadmium than is added every year under normal fertiliser use in cacao farms in Latin America, therefore, the risk of cadmium input in soils and cacao beans from fertilisers can be considered negligible.
• In soils with acid pH (< 5,5), farmers should avoid fertilisers that promote acidification e.g. urea and ammonium sulphate) because it may cause Cd to become more available to the cacao trees.
• We find that most fertilisers commonly used in cacao farms in Ecuador, Peru and Colombia comply with the recommended cadmium limits for fertilisers as established by the European Union.
• Artisanal organic fertilisers appear to be those most likely to exceed recommended EU Cd limits although this risk may be offset as organic matter buffers against Cd availability.
• We recommend that authorities enforce compliance of cadmium limits in fertilizers and that this information is readily available and can be interpreted easily by farmers.
• In conclusion, while the risk of increased cadmium accumulation in cacao beans from fertilisers appears to be minimal, where possible, farmers should use fertilisers that comply with maximum Cd limits suggested by the EU. This reduces the risk of food contamination, while ensuring that farmers can continue to fertilise their crops and attain profitable yields.