HBM4EU chromates study - PFAS exposure in electroplaters and bystanders

Area of Science:

• Environmental Health
• Occupational Health
• Toxicology

Background:

• Per- and polyfluoroalkyl substances (PFAS) are widely used industrial chemicals with growing concerns about human exposure.
• Hexavalent chromium (Cr(VI)) exposure is a known occupational hazard in various industries, including chrome plating and welding.
• Limited data exists on the co-exposure of workers to PFAS and Cr(VI) across different industrial sectors.

Purpose of the Study:

• To investigate and compare perfluoroalkyl substance (PFAS) exposure levels in workers occupationally exposed to hexavalent chromium (Cr(VI)) versus control groups.
• To identify specific PFAS compounds and their association with different industrial roles involving Cr(VI) exposure.

Main Methods:

• Plasma samples from 172 workers across 4 countries were analyzed for 8 perfluoroalkyl carboxylic acids and 4 perfluoroalkyl sulfonic acids.
• Participants included chrome plating workers (n=52), welders (n=43), surface treating workers (n=3), and unexposed controls (n=74).
• Statistical analysis was performed to compare PFAS levels between exposed groups and controls.

Main Results:

• Significant differences in perfluoroalkyl sulfonic acid (PFAS) levels were observed between Cr(VI)-exposed workers and controls.
• Perfluorooctane sulfonic acid (PFOS) showed particularly elevated levels in chrome plating workers (median 4.83 μg/l, max 789 μg/l) and welders (median 4.97 μg/l, max 1513 μg/l).
• Control group exhibited considerably lower PFOS levels (median 3.65 μg/l, max 13.9 μg/l).

Conclusions:

• Occupational exposure to hexavalent chromium is associated with elevated levels of certain PFAS, notably PFOS.
• The high PFOS levels in chrome plating workers and welders likely stem from the historical use of PFOS as mist suppressants in electroplating baths.
• This highlights potential risks for workers involved in Cr(VI) related industries due to legacy PFAS contamination.