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Linus Pauling Institute at Oregon State University Chromium (VI) is derived from chromium (III) by heating at alkaline pH and is used as a source of chromium for industrial purposes. Hexavalent chromium or chromium (VI) is a recognized carcinogen. Although the requirement for chromium is not known to be higher for older adults, one study found that chromium concentrations in hair, sweat, and urine decreased with age (28). lpi.oregonstate.edu /infocenter/minerals/chromium   (2677 words)

Hexavalent chromium monitor - Patent 6878943 The hexavalent chromium monitor of claim 1, wherein the processor is electronically coupled to the pH sensor and the photodetector, wherein the processor receives the pH signal and the absorption signal and determines a current concentration value of hexavalent chromium in the liquid from the pH signal and the absorption signal. The hexavalent chromium monitor of claim 18, wherein the processor is electronically coupled to the pH sensor and the photodetector, wherein the processor receives the pH signal and the absorption signal and determines a current concentration value of hexavalent chromium in the liquid from the pH signal and the absorption signal. The hexavalent chromium monitor of claim 30, wherein the monitoring means comprises a photodetector in communication with the second end of the waveguide for measuring the absorption of the radiation emitted by the light source by the liquid in the sample cell; wherein the photodetector generates an absorption signal. www.freepatentsonline.com /6878943.html   (7315 words)

AQ Monitoring Results: Fresno: Hexavalent Chromium at Fremont School Hexavalent chromium can get into the air as mist if it is in sprayed liquids, dust if solid material containing this chemical is dumped, scooped, or ground, and as fumes during welding or melting of metals containing hexavalent chromium. Hexavalent chromium is one type of chromium compounds (with a 6+ oxidation state chromium). Hexavalent chromium represents approximately 3% of the potential cancer risk of the nine measured compounds and the estimated diesel particulate matter. www.arb.ca.gov /ch/aq_result/fresno/frs_cr6.htm   (497 words)

AVMAZON : Chromium Picolinate, 200mcg, 150 tablets Hexavalent chromium forms as a byproductof certain industrial processes such as the making of stainless and hard-alloysteels and in the manufacture of certain pigments. Hexavalent chromium has been shown to be carcinogenic in humans, especiallywhen inhaled as a dust. Since chromium supplementation has beenassociated with decreased insulin levels, it is tempting to speculate that it isthrough this effect (that is, decreasing insulin resistance with the attendantdrop in circulating insulin) that chromium works in altering body composition. www.avmazon.com /store/chromium-picolinate-200mcg-15.htm   (2991 words)

[No title]   (Site not responding. Last check: 2007-11-01) Chromium is a naturally occurring metallic element that can be found in water and in soil or rocks. The most common forms of chromium are trivalent (chromium 3) and hexavalent (chromium 6); in its trivalent state, the chromium atom is missing three electrons, and in its hexavalent state, it is missing six electrons. Chromium 3 is an essential nutrient and is necessary for the metabolism of sugars and for many enzyme reactions. www.envtox.ucdavis.edu /cehs/TOXINS/chromium6.htm   (550 words)

Chromium (VI) (CASRN 18540-29-9), IRIS, Environmental Protection Agency Concentrations of hexavalent chromium in environmental media that are protective of carcinogenic and noncarcinogenic effects are likely to be lower than the concentrations required to cause induction of allergic contact dermatitis. Hexavalent chromium is known to be carcinogenic in humans by the inhalation route of exposure. Hexavalent chromium is mutagenic in bacterial assays, yeasts, and V79 cells, and Cr(VI) compounds decrease the fidelity of DNA synthesis in vitro and produce unscheduled DNA synthesis as a consequence of DNA damage. www.epa.gov /iris/subst/0144.htm   (8548 words)

Chromium six Hexavalent chromium enters the body in two ways: by being inhaled or by being swallowed. Hexavalent chromium materials are used in many jobs, but three jobs in particular involve frequent and/or heavy chromium exposure. Chromium fume is created by welding or cutting on stainless steel or metals that are coated with a chromium material. www.dhs.ca.gov /ohb/HESIS/cr6.htm   (2259 words)

Chromium Contamination in SFV CHROMIUM CONTAMINATION IN The San Fernando Valley (SFV) Basin is an important source of drinking water for the Los Angeles metropolitan area, the cities of Glendale, Burbank, and San Fernando, La Canada- Flintridge, and the unincorporated area of La Crescenta. Hexavalent chromium (Cr+6), however, forms very soluble, non-reactive compounds in groundwater and is highly toxic to organisms and plants. The existence of hexavalent chromium in the environment is associated with industrial waste from metal plating operations, as an example. www.swrcb.ca.gov /rwqcb4/html/water_qty/chromium_S1.html   (1488 words)

CHROMIUM Chromium (Cr) is an essential trace mineral nutrient required for normal sugar and fat metabolism. Chromium occurs primarily in the trivalent and hexavalent forms; the form in higher organisms is trivalent. Chromium increased the phosphorylation of the insulin receptor leading to enhanced insulin sensitivity. www.tjclarkinc.com /minerals/chromium.htm   (434 words)

Reduction of Hexavalent Chromium Concentrations using a Fixed Bed Bioreactor Total chromium is measured by an atomic absorption spectrophotometer, and hexavalent chromium is measured by a colorimetric spectrophotometer. Chromium can be potentially recovered by extracting the accumulation of Cr in the biomass, and chromium that has been reduced to 3+ will potentially precipitate or adhere to soil particles. Chromium sorption and reduction in soil with implications to bioremediation. www.calpoly.edu /~ceenve/pal/lab/research/criv_r1.html   (1272 words)

| Chromium, Benefits and Dangers of Chromium Picolinate, Chroma Crystal-lean, Hexavalent Chromium | Wellfx.com Infobase ... Chromium must be converted to a biologically active form for physiological function. Chromium may potentiate insulin action through direct action on insulin or its receptor, or it may regulate the synthesis of a molecule that potentiates insulin action. Chromium may alleviate chronic headaches and contribute to the treatment of acne, which appears to be caused in part by disturbed insulin metabolism. www.wellfx.com /InfoBase/chromium.html   (1030 words)

Chromium deficiency - Wikipedia, the free encyclopedia Chromium deficiency is a disorder that results from an insufficient dietary intake of chromium. Trivalent chromium is an essential trace metal and is required for the proper metabolism of sugar in humans. Chromium picolinate is the most commonly used synthetic supplement to correct imbalances in glucose metabolism due to chromium deficency. en.wikipedia.org /wiki/Chromium_deficiency   (209 words)

CAS :: Hexavalent Chromium, Cr(VI) Chromium occurs in the environment primarily in two valence states, trivalent chromium (Cr III) and hexavalent chromium (CrVI). Chromium III occurs naturally (widely distributed in soils and plants, but is rare in natural waters) and is an essential nutrient (necessary for metabolism of sugar, protein and fat). Chromium VI is generally associated with industrial processes, though it does occur naturally in very small amounts. www.caslab.com /chromium.php   (319 words)

Hexavalent Chromium in Groundwater Chromium (VI), or hexavalent chromium, is generally not known to be the predominant natural form of total chromium in groundwater, with some exceptions. He stressed that hexavalent chromium was just the latest symptom of a bigger problem: the failure to recognize contamination problems and take action until after the damage has been done. He also highlighted that many of the sources of hexavalent chromium are small "mom and pop" plating operations that do not have the financial resources to clean-up large, regional contamination problems and he suggested that a State fund might be needed to implement these clean-ups. www.grac.org /hexchromedes.html   (1564 words)

REPLACING Hexavalent Chromium - plating Automotive Finishing - Find Articles For the applicator, hexavalent chromium passivations are easy to use and can be bulk applied often by a single-stage immersion and are inexpensive to make-up and operate. Hexavalent chromium salts are classified as hazardous substances (toxic, sensitizing and carcinogenic); they are environmentally and toxicologically hazardous. From 2000, a concession of 2 g of hexavalent chromium per vehicle has been available, allowing the continued use of hexavalent chromium since suitable replacement technology is still being implemented. www.findarticles.com /p/articles/mi_m0HRR/is_2001_Spring/ai_75532387   (836 words)

Hexavalent chromium - Wikipedia, the free encyclopedia Hexavalent chromium or Cr(VI) compounds are those which contain the element chromium in the +6 oxidation state. Hexavalent chromium is recognized as a human carcinogen. Hexavalent chromium is the substance against which Erin Brockovich campaigned. en.wikipedia.org /wiki/Hexavalent_chromium   (426 words)

ATSDR - ToxFAQs™: Chromium Chromium is a naturally occurring element found in rocks, animals, plants, soil, and in volcanic dust and gases. Chromium is present in the environment in several different forms. Chromium can strongly attach to soil and only a small amount can dissolve in water and move deeper in the soil to underground water. www.atsdr.cdc.gov /tfacts7.html   (853 words)

Factsheet: Eliminatring Hexavalent Chrome From Cooling Towers   (Site not responding. Last check: 2007-11-01) Hexavalent chromium is the one that is of the most concern and warrants immediate attention. While disposing the chromium bearing recirculating water into the sanitary sewer, care must be taken to exceed the hydraulic loading capacity of the existing sewer system and the discharge chromium concentrations permitted by the local sanitation district. Hexavalent chromium based treatment chemicals have traditionally been used for this purpose because they are the most efficient and cheapest among commercially available treatment chemicals. es.epa.gov /techinfo/facts/ca-htm/htmfact3.html   (2323 words)

PF Online Feature Article - Replacing Hexavalent Chromium in Passivations on Zinc Plated Parts Chromate passivation systems contain- ing hexavalent chromium compounds are an extremely versatile group of aqueous chemistries that are extensively used in a diverse range of electroplating and metal treatment processes. (Hexavalent chromium passivations are based on a thick, gelatinous trivalent chromium layer known as the olation polymer.) Final adsorption into a topcoat of hexavalent chromate then takes place (see Table II). Contained in the directive is an assigned concession of 2 gms of hexavalent chromium per vehicle, allowing the continued use of hexavalent in the interim since it is recognized that suitable replacement technology is still being developed and implemented. www.pfonline.com /articles/020102.html   (2186 words)

C. Hexavalent Chromium Chromium, both hexavalent and trivalent forms, is an industrial material that has been used throughout the metal finishing industry for many years. Additionally, hexavalent chromium is produced in solutions when chromium is stripped from steel using anodic treatment in alkali solutions. Chromium, especially hexavalent chromium, has come under increasing regulatory scrutiny because of its listing as a human carcinogen with an inhalation exposure pathway. www.nmfrc.org /pdf/rdcsi/secIIC.htm   (628 words)

Safety and Health Topics: Hexavalent Chromium U.S. Department of Labor’s OSHA Settles the Surface Finishing Industry Council’s Challenge to the Hexavalent Chromium Standard. OSHA is correcting errors in the final rule addressing occupational exposure to hexavalent chromium that appeared in the Federal Register on February 28, 2006. OSHA proposes to lower its permissible exposure limit (PEL) for hexavalent chromium and for all Cr(VI) compounds from 52 to one microgram of Cr(VI) per cubic meter of air as an 8-hour time weighted average. www.osha.gov /SLTC/hexavalentchromium   (549 words)

Chemical Fact Sheets -- Chromium It is the most toxic form of chromium, and is shown to cause lung cancer when workers are exposed to high air levels for long time periods. Chromium can pass through the skin, but this is probably not a major route of exposure. Based on the formula, we recommend levels of hexavalent chromium in air be no higher than 0.0002 milligrams per cubic meter of air (mg/m3). www.dhfs.state.wi.us /eh/ChemFS/fs/chromium.htm   (744 words)

Hexavalent Chromium | Shipbuilders Council of America Occupational studies have shown exposure to hexavalent chromium dust to be associated with lung cancer. Ingestion (accidental or intentional) of hexavalent chromium may cause stomach upsets, ulcers, and severe damage to the kidneys and liver. Chromium in biologic tissues is almost always trivalent and helps to maintain normal metabolism of glucose, protein and fat. www.shipbuilders.org /root.asp?guid=245   (763 words)

Environ Health Perspect 108-9, 2000: Reflections on Hexavalent Chromium: Health Hazards of an Industrial Heavyweight   (Site not responding. Last check: 2007-11-01) Chromium metal does not occur naturally; it is produced from chrome ore. Trivalent chromium (Cr[III]) occurs naturally in rocks, soil, plants, animals, and volcanic emissions. Hexavalent chromium (Cr[VI]) is produced industrially when Cr(III) is heated in the presence of mineral bases and atmospheric oxygen (for instance, during metal finishing processes). He also says that the levels of chromium forms need to be detected in various media that are associated with various routes of exposure, and that applications of biomarkers must be coupled to physical or chemical markers of exposures and validated for use in situations that assess environmental health. www.ehponline.org /docs/2000/108-9/focus.html   (3635 words)

ALTERNATIVES to Hexavalent Chromium and Chromium Plating Automotive Finishing - Find Articles Trivalent chromium is the most popular alternative to hexavalent chromium already on the market; however, it is seen as only a temporary measure since it is still chromium. Regulations controlling the use and disposal of trivalent chromium baths are not as strict as those for hexavalent chromium baths. Nickel-iron-cobalt (Ni-Fe-Co) alloy substitutes for chromium plating are said to have a wear resistance twice that of chromium and corrosion resistance that is 2.6 times greater. www.findarticles.com /p/articles/mi_m0HRR/is_2000_Winter/ai_75577967   (844 words)

CHROMIUM - Reduces insulin resistance. Hexavalent chromium forms as a byproduct of certain industrial processes (such as the making of stainless and hard-alloy steels and in the manufacture of certain pigments; the name chromium comes from the Greek word for color). Since chromium supplementation has been associated with decreased insulin levels, it is tempting to speculate that it is through this effect (that is, decreasing insulin resistance with the attendant drop in circulating insulin) that chromium works in altering body composition. The first few decades of chromium research was complicated by contamination of the food or tissues being examined by significant amounts of chromium from the environment (the use of stainless steel laboratory equipment, for example). www.luminet.net /~wenonah/hydro/crbacker.htm   (3369 words)

Hexavalent Chromium - NIOSH Topic Page Hexavalent chromium (Cr(VI)) compounds are a group of chemical substances that contain the metallic element chromium in its positive-6 valence (hexavalent) state. Field method for the determination of hexavalent chromium by ultrasonication and strong anion-exchange solid-phase extraction. This document offers preventative measures to reduce the harmful physical effects of hexavalent chromium, explains how employees can be exposed to it, and highlights some of the final standard's requirements. www.cdc.gov /niosh/topics/hexchrom   (934 words)

Safety and Health Topics: Hexavalent Chromium - Hazard Recognition Workers in many different occupations are exposed to hexavalent chromium (Cr(VI)). Stainless steel welding involves the greatest exposure to hexavalent chromium. Hexavalent chromium is considered a potential lung carcinogen. www.osha.gov /SLTC/hexavalentchromium/recognition.html   (658 words)

Hexavalent Chromium, Cr(VI), Analysis Chromium exists primarily in trivalent (Cr(III)) or hexavalent (Cr(VI)) oxidation states. However, as in any colorimetric analysis, this test is subject to positive interferences from other colored materials in the sample as well as from other elements that form colored complexes with DPC. This interference appears to be due to a reaction of permanganate with the post-column reagent that gives a colored species with much less absorbance at 540 nm than either permanganate itself or the complex of chromium species with the post-column reagent. www.wcaslab.com /tech/hexchrom.htm   (635 words)

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