What is Hexavalent Chromium?
Hexavalent chromium (Cr(VI)) compounds are a group of chemical substances that contain the metallic element chromium in its positive-6 valence (hexavalent) state. Generated anthropogenically, Cr(VI) readily penetrates biological membranes. Occupational exposures to Cr(VI) occur during the production of stainless steel, chromate chemicals, and chromate pigments. Cr(VI) exposures also occur during other work activities such as stainless steel welding(particularly stick welding), thermal cutting, chrome plating, painting, and coating processes. Furthermore, chromium is found in many natural materials such as limestone, which is used to make portland cement.
As of May 14th, 2010, OSHA published a final standard for occupational exposure to Cr(VI) and revised the notification requirements. The final document reduces the permissible exposure limit (PEL) ceiling to an 8-hour time-weighted average (TWA) of 5 ug/m3, with an Action Level (AL) of 2.5 ug/m3 for Cr(VI) compounds. NIOSH considers all Cr(VI) compounds to be potential occupational carcinogens and recommends an exposure limit of 1 ug/m3 for a 10-hour TWA for all Cr(VI) compounds.
An increased risk of lung cancer has been demonstrated in workers exposed to Cr(VI) compounds. Other adverse health effects associated with Cr(VI) exposure include dermal irritation, skin 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 the teeth. SAI is IHLAP accredited for Hexavalent Chromium under Ion Chromatography (IC)
Hexavalent Chromium-containing Products
- Textile Dyes
- Stainless Steel
- Wood Preservatives
- Leather Tanning
Why Choose SAI?
With stronger regulations, litigation and more enforcement on the horizon, Scientific Analytical Institute has seen the increased demand for hexavalent chromium analysis. Due to it’s significance as a formidable industrial hygiene issue we have responded by obtaining the best analytical instrumentation on the market. Our Dionex ICS-1000 Ion Chromatograph with a Variable Wavelength UV/Vis Detector is paired with an adept staff of chemists who respond abruptly and personally to your project’s individual needs. SAI is happy to provide our clients with results within 24 hours of submission or in as long as 5 days for our standard turnaround. By utilizing a modified OSHA ID 215 analytical method, SAI assures your clients that they are getting the most up to date and accepted test for Cr(VI). OSHA’s Salt Lake Technical Center lists the advantages of OSHA ID 215 as being the following:
- 1.3.1 This method has adequate sensitivity for determining compliance with the proposed OSHA TWA and AL PELs for Cr(VI) exposure.
- 1.3.2 The method is simple, rapid, and easily automated.
- 1.3.3 The method is specific and can determine Cr(VI) in the presence of Cr(III). Most heavy metals, such as vanadium, copper, iron (III), and molybdenum, do not significantly interfere. Fe(II) appears to cause a negative interference during sampling and storage (see Sections 1.5 and 4.4 for further information).
- 1.3.4 By using alkaline extraction conditions (pH = 10 to 11) in which Cr(VI) is more stable, sample recovery is improved by preventing Cr(VI) losses which may occur in a more acidic extraction media. Both water soluble and insoluble Cr(VI) compounds are soluble in the alkaline (carbonate/ bicarbonate/Mg(II)/phosphate) buffer. The extraction medium specified in this method minimizes the possible interferences.
- 1.3.5 Extraction and preparation of samples for analyses involve simple procedures and equipment.
- 1.3.6 If necessary, the amount of Cr(VI) can also be analyzed and confirmed by differential pulse polarography (DPP), provided samples and standards are matrix-matched. This DPP technique is described in reference 5.8.
SAI will continue to provide you what you expect from our quality oriented laboratory: Up to date information, timely analysis, dedicated chemists, top of the line instrumentation and personalized support. Join the ranks of our growing list of satisfied customers who choose quality. Choose SAI for all your analytical service needs.