Sb – Antimony is found in igneous rock at 0.2 ppm; shales at 1.5 ppm; sandstones at 0.05 ppm; limestone at 0.2 ppm; sea water at 0.00033 ppm; soil at 2 to 10 ppm; land plants at 0.06 ppm; land animals at 0.006 ppm (concentrates in mammalian heart muscle).
Antimony potassium tartrate (tartar emetic) is still used today as the preferred treatment for blood flukes (schistosomiasis or Bilharziasis).
Antimony has no known function in living organisms and is not among the more toxic elements. Data on the metabolism of this element are therefore meager. Smith (1967) was one of the first to use neutron activation to examine a range of human organs and found antimony present in all of them.
Published antimony levels in individual foods or animal feedstuffs are not very extensive, although it has long been known that foods stored in enamel vessels and cans may contain appreciable antimony concentrations. Oakes et al. analyzed 21 fruits and vegetables and found that most of them contained < 1.0 ng antimony per gram fresh weight. The only exceptions were sweet potato and green peppers, which contained 4.2 and 3.0 ng/g, respectively. Furr and coworkers in 1979 found that nuts were relatively high in antimony (50-300 ng/g dry weight), and that kernels of apricots and other fruits that may be sold in health food stores were slightly lower in antimony than were nuts (20-150 ng/g dry weight). They also reported that the antimony concentration in maple syrup was normally 300 ng/g dry weight, but was 800 ng/g dry weight if obtained from trees near highways. Cowgill (1981) reported that fresh banana pulp contained 8.3 ng antimony per gram.
Interest in the metabolism of antimony developed following the discovery by Christopherson that the trivalent Sb compound tartar emetic is effective in the treatment of schistosomiasis. Tartar emetic and other antimonials when regularly injected significantly raise the Sb levels of most tissues and blood and particularly that of the red cells. Several workers have demonstrated the affinity of trivalent antimony for red blood cells both in vivo and in vitro. It has been suggested that the therapeutic value of the Sb compounds lies in part in this fact since the adult worms digest the erythrocytes. By contrast the red cells are almost impermeable to pentavalent Sb compounds in man. Trivalent Sb can readily be demonstrated in schistosomes, especially female schistosomes, following injection of infected mice with tartar emetic
Lifetime studies with mice fed 5 ppm Sb as antimony potassium tartrate in the drinking water revealed no demonstrable toxic effects on males and a slight decrease in life span and longevity and some suppression of growth of older animals in females. No evidence of carcinogenesis or tumorigenesis was obtained. On this basis antimony must be considered to have a low inherent toxicity.