Summary_of_the_Use_of_Hexavalent_Chromium

Specification and Use of Hexavalent Chromium. Summary Report by Mark Lodge Introduction: The façade specifications on the Qatar Petroleum District Project allow for Chromium conversion treatment of aluminum sections as a surface preparation prior to painting. The contractor has proposed hexavalent chromium to be used. The substance would be applied in the façade producers’ factory in the Peoples Republic of China. Concern has been raised that hexavalent chromium represents a cancer risk and that it is actually banned in many parts of the world. 1. Overview of the substance: Hexavalent chromium (also called chromium-6) is one form of the metallic element chromium, which is listed in the periodic table. Characteristics of Chromium Chromium is odorless and tasteless. It occurs naturally in various types of rock, soil, ore and volcanic dust as well as in plants, animals and humans. Three Common Forms of Chromium The most common forms of chromium in the environment are trivalent chromium (chromium-3), hexavalent chromium (chromium-6) and the metal form of chromium (chromium-0). Chromium-3 occurs naturally in many vegetables, fruits, meats and grains, and in yeast. It is an essential nutritional element for humans and is often added to vitamins as a dietary supplement. Chromium-3 has relatively low toxicity. Uses of Hexavalent Chromium Hexavalent chromium and chromium-0 are generally produced by industrial processes. Chromium-0 is used primarily for making steel and other alloys. Hexavalent chromium is used for chrome plating and the production of stainless steel as well as leather tanning, wood preservation, textile dyes and pigments. Hexavalent chromium is also used in anti-corrosion and conversion coatings. Potential Dangers of Hexavalent Chromium Hexavalent chromium is a known human carcinogen when it is inhaled, and can pose a serious health risk to workers in industries where it is commonly used. Although the potential health risk of hexavalent chromium in drinking water is a growing concern in many communities and at the national level, there is not yet enough scientific evidence to confirm the actual risk or to determine at what level of contamination it occurs. What are the Health Risks Associated with Hexavalent Chromium' Hexavalent chromium is recognized as a human carcinogen when it is inhaled. Chronic inhalation of hexavalent chromium has been shown to increase risk of lung cancer and may also damage the small capillaries in kidneys and intestines. Other adverse health effects associated with hexavalent chromium exposure, according to the National Institute for Occupational Safety and Health (NIOSH), include skin irritation or ulceration, allergic contact dermatitis, occupational asthma, nasal irritation and ulceration, perforated nasal septa, rhinitis, nosebleed, respiratory irritation, nasal cancer, sinus cancer, eye irritation and damage, perforated eardrums, kidney damage, liver damage, pulmonary congestion and edema, epigastric pain, and erosion and discoloration of one's teeth. Hexavalent Chromium: An Occupational Hazard NIOSH considers all hexavalent chromium compounds to be potential occupational carcinogens. Many workers are exposed to hexavalent chromium during the production of stainless steel, chromate chemicals and chromate pigments. Hexavalent chromium exposure also occurs during work activities such as stainless-steel welding, thermal cutting and chrome plating. 2. Legislation/Regulatory : From research carried out the substance is not banned per se, however, due to the known adverse health effects the use of the substance is very stringently regulated in countries around the world with developed Health and Safety legislation. The newly revised Qatar Construction Specification (QCS 2010) do not reference specific substances, however, principles of The Hierarchy of Risk Management are applicable. 3. Risk Management : International HSE law and best practice dictates through the Hierarchy of Risk Management that where practicable Hazards should always be eliminated at source. 4. CSR KEO, as a professional and socially responsible organisation are ideally placed and have a unique opportunity to influence the design and eliminate the use of known carcinogens through specification of alternative materials, thereby eliminating exposure and potential adverse health effects to workers in the supply chain. Moreover, with the inevitable world focus on the Qatar Construction Industry in the near future the specification and use of alternatives to known carcinogens could be cited by the Client/Designer/PM/Engineer as a prime example of sensible supply chain specification and management.