CADMIUM IN AGRICULTURE

Phosphate fertilizers contain varying amounts of cadmium as contaminants from phosphate rock. Plant uptake of cadmium from fertilized soils could conceivably result in entry of cadmium into the human food chain. To keep the cadmium-concentration in agricultural products below the maximum permissible levels, “critical” levels of cadmium-concentrations in top soil are evaluated. Based on a calculated rise of 0.2 mg cadmium/kg soil per hundred years, the “critical” value for cadmium in Dutch soils will be reached in one century in the case of sandy soils and in three centuries in the case of clay soils. However, the observed increase in cadmium in long-term fertilizer trials is lower than the calculated amount of 0.2 mg per kg in hundred years. As a consequence the “critical” date will be delayed even further. © 1990, Taylor & Francis Group, LLC. All rights reserved.