(1) Organometallic chemicals contain at least one covalent bond between a carbon atom and a metal. The general advice seems to be "take just enough but not too much," which isn't too different from dosing advice for all vitamins and drugs. What about people who are B 12 deficient but also allergic to cobalt? They cannot avoid the cobalt since it is part of the vitamin. So, people who are allergic to B 12 are actually reacting to the presence of cobalt, which is similar in properties to nickel - a known allergen. Furthermore, allergy to multiple metals and metal alloys has been demonstrated. Source: Nritya Creations (Right) Cobalt and nickel are neighbors on the periodic table. (Left) A skin patch test showing allergies to both cobalt and nickel. Once you develop a nickel allergy, however, you'll always be sensitive to the metal and need to avoid contact."įigure 3. Treatments can reduce the symptoms of nickel allergy. It may take repeated or prolonged exposure to items containing nickel to develop a nickel allergy. "Nickel allergy is a common cause of allergic contact dermatitis - an itchy rash that appears where your skin touches a usually harmless substance. This shouldn't be too surprising since nickel happens to be a known skin allergen and a cause of eczema and contact dermatitis. And nickel just happens to reside right next to cobalt on the periodic table. Perhaps the nickel reaction is even more pronounced than that from cobalt. Figure 3 shows a cobalt skin patch test that also includes nickel. Why would anyone be allergic to cobalt? Chemistry gives us an answer. A cobalt allergy can be confirmed by a skin patch test (Figure 2).įigure 2. Vitamin B 12 is essential for every cell in the human body (animals too), so it may seem strange, but some people are allergic to it and they can suffer either an acute or chronic itchy rash that can have small blisters containing a clear fluid, skin that is red, swollen, oozing, or peeling. This motif is nature's way of binding organic metals to metals. Note that in all three molecules metal ions are coordinated - held in the middle - of four nitrogen atoms (yellow stars) which are part of five-membered rings. (Right) Partial structure of chlorophyll (Magnesium is in the green circle). (Center) Heme, the "business end" of hemoglobin (Iron is in the red circle). (Cobalt is in the blue circle, cyanide in the red circle). Biologically important metal coordination complexes: (Left) Cyanocobalamin, one of the forms of Vitamin B 12. Although cobalt-containing biomolecules are rare in nature, cyanocobalamin is structurally very similar to two other common organometallic (1) molecules, heme, and chlorophyll (Figure 1).įigure 1. Despite one molecule of cyanide there isn't a whole lot to be scared about Vitamin B 12, but in rare circumstances, it is this:Ĭyano COBALamine (COBAL being short for the metal cobalt). If there is anything scary sounding about any of them, most people would pick:īut they'd be wrong. Consider three names for the chemical below. The Cobalt Dichloride humidity indicator card is available in the standard JEDEC required format indicating 5, 10 and 60% RH, a 6 spot 10-60% RH Card (similar to the AEC826004NE) and a 4 spot 10-40% RH Card (similar to the HM-04 HIC).Contrary to what the Food Babe says, the spelling, length, or pronunciation of a chemical has absolutely nothing to do with its health properties, good, bad, or neither. The Humitector CDF provides verifiable color-change accuracy as required by JEDEC standard J-STD-033B, as well as exceeds applicable regulations administered by the ECB. Some companies have expressed the desire to begin using a Cobalt Dichloride Free humidity indicator card. Meet European Chemical Bureau (ECB) REACH directivesĬobalt Dichloride Free Humidity Indicator Cards offer the electronics and semiconductor industries a Cobalt Dichloride (CoCl2) Free humidity indicator (HI) card, while maintaining the accuracy required by international JEDEC standards.Ĭobalt Dichloride Free Humidity Indicator Cards provide electronic and semiconductor manufacturers with a JEDEC compliant humidity indicator card that is free of Cobalt Dichloride, a chemical regulated under European Chemical Bureau (ECB) REACH directives.
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