Be – Beryllium is found in igneous rocks at 2 to 8 ppm; shale at 3 ppm; sandstone and limestone < 1.0 ppm; fresh water 0.00 1 ppm; sea water at 0.0000006 ppm; soil at 0. 1 to 40 ppm; marine plants at 0.001ppm (highest in brown algae); land plants at < 0.1 ppm (highest in volcanic soils); land animals at 0.0003 to 0.002 ppm in soft tissue.
Certain beryllium compounds are carcinogenic when inhaled, and osteosarcomas have been produced by the intravenous injection of several beryllium salts. However, ingested beryllium is not especially toxic. Beryllium, fed to rats at the level of 5 mcg/ml drinking water for a lifetime, was virtually innocuous as measured by median life span, longevity, incidence of tumors, and serum cholesterol and uric acid. Apparently beryllium is poorly absorbed through the gut, and thus ingestion is not a hazard, especially considering the low levels apparently present in food. However, like other trace elements given in high doses, ingested beryllium can be toxic, causing severe rickets not cured by cholecalciferol and inhibiting alkaline phosphatase of several tissues. Although beryllium apparently occurs in very low levels in human tissues, it was found to occur in blood and serum at concentrations of 0.019 and 0.017 mcg/g, respectively.