Chromium inhalation

TABLE 2-1. Levels of Significant Exposure to Chromium - Inhalation... 

Malsch PA, Proctor DM, Finley BL. 1994. Estimation of chromium inhalation reference concentration using the benchmark dose method a case study. Regul Toxicol Pharmacol 20 58-82. 

The primary routes of entry for animal exposure to chromium compounds are inhalation, ingestion, and, for hexavalent compounds, skin penetration. This last route is more important in industrial exposures. Most hexavalent chromium compounds are readily absorbed, are more soluble than trivalent chromium in the pH range 5 to 7, and react with cell membranes. Although hexavalent compounds are more toxic than those of Cr(III), an overexposure to compounds of either oxidation state may lead to inflammation and irritation of the eyes, skin, and the mucous membranes associated with the respiratory and gastrointestinal tracts. Skin ulcers and perforations of nasal septa have been observed in some industrial workers after prolonged exposure to certain hexavalent chromium compounds (108—110), ie, to chromic acid mist or sodium and potassium dichromate. 

Reproductive Toxicity. No data are available that impHcate either hexavalent or trivalent chromium compounds as reproductive toxins, unless exposure is by way of injection. The observed teratogenic effects of sodium dichromate(VI), chromic acid, and chromium (HI) chloride, adininistered by injection, as measured by dose-response relationships are close to the amount that would be lethal to the embryo, a common trait of many compounds (111). Reported teratogenic studies on hamsters (117,118), the mouse (119—121), and rabbits (122) have shown increased incidence of cleft palate, no effect, and testicular degeneration, respectively. Although the exposures for these experiments were provided by injections, in the final study (122) oral, inhalation, and dermal routes were also tried, and no testicular degeneration was found by these paths. 

Cadmium and inorganic compounds of cadmium in air (X-ray fluorescence spectroscopy) Chromium and inorganic compounds of chromium in air (atomic absorption spectrometry) Chromium and inorganic compounds of chromium in air (X-ray fluorescence spectroscopy) General methods for samphng and gravimetric analysis of respirable and inhalable dust Carbon disulphide in air... 

Chromium (Cr) Associated with insulin Food supply Kidney damage, lung cancer (inhalation) 50 to 200 pg (Cr3-)... 

While chromium metal or trivalent chromium is not very toxic, hexavalent chromium (Cr +) is carcinogenic and moderately toxic. Cr + is corrosive to skin and causes denaturation and precipitation of tissue proteins. Inhalation of Cr6+ dust or mist can cause perforation of the nasal septum, lung irritation, and congestion of the respiratory passsages. Chronic exposure may produce cancer of the respiratory tract. 

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