Health Hazard Evaluation Report HETA 85-064-1844, GTE/Valenite Corporation, Westminster, South Carolina

摘要

In response to a confidential request, an evaluation of exposure to hard metal dusts was made at GTE/VALENITE Corporation (SIC-3541), Westminster, South Carolina, employing 50 production workers. Dusts were generated during finish grinding of tungsten carbide cutting tool inserts. Personal and area air samples were analyzed for seven nitrosamines, cobalt (7440484), and tungsten (7440337). No nitrosamines were detected. Cobalt levels were nondetectable to 26.8 micrograms/cubic meter (microg/m3) (American Conference of Governmental Industrial Hygienists Threshold Limit Value, 50microg/m3). Tungsten levels were nondetectable to 0.41mg/m3 (NIOSH Recommended Exposure Limit, 5mg/m3). Medical survey of 35 workers showed respiratory symptoms associated with length of employment and smoking status. Symptoms did not correlate with exposure category. Personal air samples were taken for cobalt for ten workers giving urine samples pre and post shift. All had increased urine cobalt levels over shift. There was no correlation between total airborne and urine cobalt levels, but there was a significant association for post shift urinary and respirable cobalt. The authors recommend that air sampling for tungsten carbide and cobalt be continued. Good housekeeping and personal hygiene practices should be instituted and maintained. Change to a safer cutting fluid is recommended along with a medical surveillance program and careful follow up of employees with persistent symptoms of cough, chest tightness, shortness of breath, or wheezing.