Beryllium chromate

Beryllium Chromate, BeCrO4.H20, and the basic eonqrouud, EeCr04.6Ee(0TI).2, have been described by Glassmaun, whose results, however, have not been confirmed by subsequent workers. It appears to be established that a solution of chromic acid absoi bs beryllium hydroxide in the exact ratio of iBe(OH)., K rOj, w hich points to the formation of the neutral chromate. When solutions of beryllium salts are treated with equivalent quantities of chromates, the prccij titates at first formed redissolve but if the chromate is added in excess, yellow precipitates of strongly basic beryllium chromates of uncertain composition are obtained. 

Arsenic, asbestos, benzo(a)pyrene, hK(chloromethyl)ether, chromium, nickel subsulfide, zinc chromate, tobacco, mustard gas, uranium, acrylonitrile, beryllium, cadmium, l,2-dibromo-3-chloropropane, polyaromatic hydrocarbons (PAHs)... 

The big environmental and health concerns led to the avoidance of many substances that have been used in the past in p5TOtechnic mixtures. These include beryllium, cadmium, mercury, chromates, lead compounds, and many others. 

The primary routes of potential human exposure to coke oven emissions are inhalation and dermal contact. Occupational exposure to coke oven emissions may occur for those workers in the aluminum, steel, graphite, electrical, and construction industries. Coke oven emissions can have a deleterious effect on human health. Coke oven emissions contain literally several thousand compounds, several of which are known carcinogens and/or cocarcinogens including polycyclic organic matter from coal tar pitch volatiles, jS-naphthylamine, benzene, arsenic, beryllium, cadmium, chromate, lead, nickel subsulfide, nitric oxide, and sulfur dioxide. Most regulatory attention has been paid to coal tar pitch volatiles. 

Metals Nickel, cobalt, mercury, silver, chromates (welding fumes and cement), beryllium... 

Finally, the Ames assay is not particularly useful for detecting carcinogenic metals and minerals. With the exception of chromate, the assay failed to give a positive reaction with either cadmium, nickel, or beryllium salts or asbestos. " Salts of cadmium, nickel chromium, and beryllium were positive, however, in an in vitro cell transformation assay. 

Humans concluded that there was sufficient evidence for the carcinogenicity of soluble calcium chromate and several relatively insoluble hexavalent chromium compounds in laboratory animals. Tumors were mainly induced at the administration site. In addition, experimental exposure to Be, Cd, Ni, and Sb has caused lung tumors in rats, while various beryllium compounds produced osteosarcomas in rabbits by implantation or injection (Hayes 1997). Rossman et al. (2001) could show a co-carcinogenic action of arsenic with solar UV radiation on mouse skin. Apparently strain as well as species differences of the susceptibility to the action of metals may cause variable outcome of carcinogenicity tests for example, in mice this is caused by higher metallo-thionein levels (Oberdorster et al. 1994, Waalkes and Rehm 1994). 

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