Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0920652 (skin irritant)
 188 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hexavalent chromium is a common skin irritant that can cause contact dermatitis in sensitized individuals. Soil samples from two chromium waste sites having different Cr(VI) concentrations were extracted in synthetic sweat solutions over a pH range of 4 to 8 and analyzed for Cr(VI). These extractions were performed to determine the potential availability of Cr(VI) from contaminated soils upon contact with human sweat. The samples were also extracted using the EPA Method 3060 alkaline digestion. Overall, hexavalent chromium was readily extractable from both samples in the solutions tested. One of the samples contained Cr(VI) crystals, known as blooms, and had a Cr(VI) concentration approximately 40 times greater than the sample without blooms. The pH of the synthetic sweat solution had little effect on the Cr(VI) concentration determined for the sample containing blooms, whereas the Cr(VI) concentration determined for the sample without blooms increased with increasing pH. The Cr(VI) extracted in the synthetic sweat solutions was consistently lower than the amount extracted by the EPA 3060 alkaline extraction.
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PMID:The extractability of Cr(VI) from contaminated soil in synthetic sweat. 754 72

ABSTRACT Chromium is a common human contact allergen, but it is not known whether chromates cause contact hypersensitivity by immunological mechanisms similar to those induced by strong haptens. To understand the immunological events of contact hypersensitivity to chromates, we investigated whether and how chromate sensitization alters lymphocyte subsets in draining lymph nodes (DLNs), blood, and spleens in mice. BALB/c mice were sensitized by painting their ears with 0.5% potassium dichromate or vehicle alone on 3 consecutive days. Flow cytometric analysis of lymphocyte surface antigens showed that the chromate exposure significantly increased the percentage of B cells and decreased the percentages of T cells in the DLNs. This was accompanied by a relative increase in T cells and a relative decrease in B cells in peripheral blood. In contrast to the chromate, sodium dodecyl sulfate (a skin irritant) did not affect B cells or T cells in the three compartments. Moreover, sensitization to the chromate led to dose-dependent decreases in the percentages of CD4(+) T cells and CD8(+) T cells in the DLNs. However, CD4(+) and CD8(+) memory T cells were significantly increased in the blood and DLNs of the chromate-sensitized mice. Additionally, the percentage of B cells in the DLNs but not blood was dose-dependently increased in the chromate-sensitized mice. Histologically, B-cell areas were dramatically enlarged in the DLNs of the chromate-sensitized mice. Thus, this report provides basic information to further elucidate the role of individual lymphocyte subsets in contact hypersensitivity to chromates.
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PMID:Contact sensitizer potassium dichromate alters lymphocyte populations in draining lymph nodes and blood in mice. 2002 Aug 74