NIOSH recommends lower exposure limit for hexavalent chromium

摘要

The US National Institute for Occupational Safety and Health (NISOH) has released a criteria document for a recommended standard for occupational exposure to hexavalent chromium (Cr[VI]). In this criteria document, NIOSH reviews the critical health effect studies of hexavalent chromium in order to update its assessment of the potential health effects of occupational exposure to Cr(VI) and its recommendations to prevent and control these workplace exposures. Having reviewed the findings, NIOSH recommends that airborne exposure to all Cr(VI) compounds be limited to a concentration of 0.2 μg Cr(VT)/m~3 for an 8-hour TWA exposure, during a 40-hour working week. The recommended exposure limit (REL) is intended to reduce workers' risk of lung cancer associated with Cr(VJ) over a working lifetime of 45 years to cancer death rate of 1 in 1000 workers. The REL previously adopted by NIOSH for all Cr(VI) compounds was 1 μg/m~3.