Reduction of hexavalent chromium collected on PVC filters

Area of Science:

• Environmental Chemistry
• Occupational Health

Background:

• Hexavalent chromium (Cr(VI)) is a known human carcinogen.
• Understanding Cr(VI) reduction in workplace settings is critical due to its environmental and health impacts.
• Limited data exists on the kinetics of Cr(VI) reduction in occupational environments.

Purpose of the Study:

• To investigate the reduction of hexavalent chromium over time under various conditions.
• To quantify the rate of Cr(VI) reduction post-mist generation and post-sampling.

Main Methods:

• A pilot chrome plating operation was simulated in a laboratory setting.
• Hexavalent chromium levels were monitored immediately after mist generation and at 1- and 2-hour intervals.
• Collected air samples on PVC filters were analyzed for Cr(VI) reduction over 2 hours post-sampling.

Main Results:

• Immediately after mist generation, hexavalent chromium comprised nearly 100% of total chromium.
• After 1 hour, Cr(VI) reduced to 87.4%, and after 2 hours, it reduced to 81.0% of total chromium.
• Collected samples showed a reduction to 90.8% Cr(VI) within 2 hours, indicating reduction during storage.

Conclusions:

• Hexavalent chromium undergoes reduction over time, both in the air after mist generation and on sampling filters.
• The reduction of Cr(VI) during storage necessitates protective measures for air samples.
• Further research is needed to fully understand Cr(VI) reduction pathways in workplace environments.