Chromate exposure in humans occurs mainly from occupational exposure to welding, printing, glues, dyes, wood ash, foundry sand, match heads, machine oils, timber preservative, engine coolants, boiler linings, television screens, magnetic tapes, tire fitting, and chrome plating. Exposure to chromium from industrial waste can also occur (U.S. DHHS 2000). Exposure is mainly to hexavalent chromium, which is reduced to trivalent chromium in the skin. Trivalent chromium is found in the epithelium and is transported bound to erythrocytes and plasma proteins. Exposure to chromium can cause an allergic dermatitis and other immunologic changes, fatal nephritis, loss of taste and smell, and hepatic cell injury. It is also a pulmonary carcinogen (U.S. DHHS 2000).

In adults, exposure to chromium by inhalation, oral or dermal contact can cause skin sensitization and eruptions, urticaria, a chromium-induced asthma, and bron-chospasms accompanied with tripling of plasma histamine levels (U.S. DHHS 2000). Cellular changes include leucocytosis or leucopenia, eosinophilia, monocytosis, and changes in the number and function of alveolar macrophages. Additionally, chromium exposure increases serum immunoglobulin levels and stimulates T cell mitogen responses (U.S. DHHS 2000). Overall, chromium causes a dysregulation of immune function resulting in immunostimulation.

Chromium crosses the placenta and concentrates in fetal tissues, and can be found in breast milk during lactation. This generally gives fetuses higher tissue concentrations than adults. Tissue concentrations in the fetus decline rapidly with age except in the lungs (U.S. DHHS 2000). Hexavalent chromium exposure during gestation results in fetal developmental abnormalities, including ossification changes and facial deformities, and morphological changes in the developing reproductive tracts (Junaid et al. 1996a, 1996b; Kanojia et al. 1998). No studies have yet inves tigated immunological changes in offspring resulting from in utero exposure to chromium, but as with cadmium, there is a possibility for some form of developmental immunotoxicity based on the current literature.

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Free Yourself from Panic Attacks

Free Yourself from Panic Attacks

With all the stresses and strains of modern living, panic attacks are become a common problem for many people. Panic attacks occur when the pressure we are living under starts to creep up and overwhelm us. Often it's a result of running on the treadmill of life and forgetting to watch the signs and symptoms of the effects of excessive stress on our bodies. Thankfully panic attacks are very treatable. Often it is just a matter of learning to recognize the symptoms and learn simple but effective techniques that help you release yourself from the crippling effects a panic attack can bring.

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