NIOSHTIC-2 Publications Search
Lead exposures in gold fire assay laboratories.
Appl Occup Environ Hyg 1991 Apr; 6(4):252-254
A survey of six gold fire assay laboratories was undertaken to assess the extent of exposure in these laboratories and to identify means of controlling exposures. During the study personal samples were collected near the breathing zones of the workers to determine 8 hour time weighted average exposures to lead (7439921). In addition, several short term personal and area samples were collected to determine the extent to which each of the various assaying tasks contributed to the airborne lead levels. At five of the six facilities blood samples were collected from workers to determine levels of blood lead and free erythrocyte protoporphyrin. In 11 personal breathing zone samples time weighted average exposures to lead ranged from 110 to 850 micrograms/cubic meter (microg/m3). All values exceeded the OSHA Permissible Exposure limits of 50microg/m3. Several specific tasks were identified which were associated with high concentrations of airborne lead during the fire assay process including a flux mixing procedure which caused a 13,000microg/m3 reading during the 38 minutes it took to be completed. A concentration of 1400microg/m3 was recorded during unloading of cupels, 100microg/m3 during hammering of the lead buttons, and 80microg/m3 during crucible pouring. Blood lead levels among the 20 workers sampled ranged from 13 to 65 micrograms/deciliter, with a mean of 37 micrograms/deciliter.
NIOSH-Author; Lead-compounds; Laboratory-workers; Air-quality-monitoring; Lead-dust; Lead-poisoning; Metal-dusts; Dust-inhalation
Issue of Publication
Applied Occupational and Environmental Hygiene
Page last reviewed: May 5, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division