a single-blind study was performed on male workers from a primary lead smelter to determine whether a daily oral supplement of vitamin c ( 1 g vitamin c orally once a day , five times a week for 20 weeks ) or zinc ( 60 mg zinc as zinc gluconate once a day , five times a week for eight weeks ) influences the absorption of and the biological ( hematological and renal ) response to lead .
C0043481
zinc
C0149381
zinc