Migration of lead in a glass-lined bottom-unloading silo

Alfalfa, estimated to contain 25.89 mg lead (Pb)/kg of air dried sample, was ensiled in a glass-lined bottom-unloading silo. Three weeks later air dried haylage from the bottom of the silo contained 118.6 mg of Pb/kg. The concentration of Pb in the haylage was sufficient to induce saturnism in a dairy herd. During the disposal process, the concentration of Pb was determined in each 11.3 m3 load of silage. These data provide evidence that Pb migrated and concentrated in the bottom of the silo.