Occupational exposure to nickel, cobalt, and chromium in the Lithuanian hard metal industry

Abstract

Background Metalworkers are said to have heavy exposure to metals, but the amount of released metal ions from alloys and deposition on the hands is unknown. Objective To analyze nickel, cobalt, and chromium in vitro release to the artificial sweat from nails and wire made of different alloys, and to test metal deposition on the fingers of metalworkers. Material and Methods Six different samples of nails and wire were kept in artificial sweat for 24 hours and one week, respectively. The metal release was determined by atomic absorption spectrometry (AAS). Eighty‐eight consecutive metal plant workers immersed their index fingers and thumbs in separate laboratory tubes filled with deionized water for 2 minutes. The sample analysis for metals was carried out with an inductively coupled plasma mass spectrometer (ICP‐MS). Results The average released concentration of Ni was 0.0012 μg/cm2, for Co it was 0.0007 μg/cm2, and for Cr 0.0037 μg/cm2 after 24 hours and 0.0135, 0.0029, and 0.0042 μg/cm2, respectively, after 1 week. There was a statistically significant increase in released concentration of Ni during one week: 0.0012 μg/cm2 vs 0.0135 μg/cm2 (P = .04). Medians of the detected Co amount on fingers reflected a statistically significant difference between workplaces: 0.004 μg/cm2 for metalworkers vs 0.001 μg/cm2 for office staff (P = .04). Conclusion Nickel (Ni), cobalt (Co), and chromium (Cr) can be released in different concentrations from nails and wire. Detected Ni and Cr levels can elicit dermatitis in already sensitized patients. Co can be extracted from alloys even if not mentioned on material safety data sheets. The finger immersion technique was used for cobalt and chromium detection on fingers for the first time.

The Penetration of Chromium: An Up-To-Date 0.5% Potassium Dichromate Vehicle Comparison

“…Only metal workers (4%) were patch tested positive to potassium dichromate. Analyzing the amount of Cr on workers' fingers by finger immersion method, 25 there are 2 types of workers: raw material operator and nail heaters who had the highest concentration of Cr left on their fingers. Those occupations involved direct and prolonged contact with hard materials that are usually covered in grease.…”