Lead in Soil & Coco Beans

Cocoa Contamination

• A lot of the cocoa shells that are used as mulch in the United States originate from Nigeria and Mexico. It has been found that much of the soil the cocoa plants are grown on is moderately contaminated with lead. In Nigeria especially, gasoline is not unleaded and therefore emissions from automobiles can put significant amounts of lead into the atmosphere and the soil, where the heavy metal is absorbed into the cocoa plant, especially in the fruit, or the bean.

Cocoa Shell Mulch

• Cocoa shell mulch is used just as any other mulch to maintain heat and moisture, as well as to provide organic material and beautification for any garden. Cocoa mulch provides organic material for the soil when it biodegrades and becomes humus full of nutrients that are accessible to plants. When the cocoa shells biodegrade, they also release the lead that was stored in them, potentially contaminating soil.

Lead in the Soil

• Though it is acknowledged by the scientific community that there is lead content in cocoa shells, it is debatable whether this lead content significantly contributes to lead levels in soil. Most soils actually do contain lead in them, but by and large these lead levels are considered by the EPA to be small enough to be safe for humans. No scientific study has undeniably shown that cocoa shell mulch has any significant impact on the lead concentration in soil.

Lead Poisoning

• Though most soil does have small amounts of lead in it, soils with large lead content can be extremely hazardous to humans, especially to children. Lead poisoning affects the central nervous system, which is still in development in children. As a result, lead poisoning can lead to severe IQ reduction, as well as learning disabilities, stunted growth and kidney failure. High lead levels in adults are not as debilitating but can cause depression, fatigue, impotence and other mental and physical disorders. Cocoa mulch has not been found to directly cause any kind of lead contamination, but it may be smart to err on the side of caution.