NATURALLY-OCCURRING RADIONUCLIDES IN TISSUE FROM BEEF FED PHOSPHATIC CLAY-GROWN FORAGES

This study was designed to determine if beef animals (Bos taurus) fed forages grown on reclaimed phosphate land accumulated selected radionu clides in muscle, kidney, or bone tissues. Sixty (60) beef steers (ave rage weight 194.5 kg) were randomly assigned to one of four treatment groups: unmined pasture (control), reclaimed pasture, full feed of alf alfa (Medicago sativa L.) hay, or full feed of corn (Zea mays L.) sila ge both grown on reclaimed phosphatic clay. Animals remained on the st udy for approximately 14 mo and were then slaughtered. Radium-226 in m uscle tissue from the reclaimed pasture treatment was 0.081 Bq kg-1 an d higher (P < 0.05) than in muscle tissue from the other three treatme nts. Radium-226 levels in kidney tissue from the unmined and reclaimed pasture treatments were higher (P < 0.05) than from both corn silage and alfalfa hay treatments. Bone Ra-226 levels were higher than both m uscle and kidney tissue (P < 0.05), but no statistically significant d ifferences were observed in bone samples among the four treatment grou ps. Results of this study indicate no food safety problems from consum ing products from beef animals fed forages grown on reclaimed phosphat e land.