Biological Monitoring of Welders' Exposure to Chromium, Molybdenum, Tungsten and Vanadium

Background: Welders are exposed to a number of metallic elements during work. Bioaccessability, that is important for element uptake, has been little studied. This study addresses bioaccessability and uptake of chromium (Cr), molybdenum (Mo), tungsten (W) and vanadium (V) among welders.

Methods: Bioaccessability of Cr, Mo, V and W was studied in airborne particulate matter collected by personal sampling of the workroom air among shipyard welders by using the lung lining fluid simulant Hatch solution. Associations between concentrations of Hatch soluble and non-soluble elements (Hatch and Hatch) and concentrations of the four elements in whole blood, serum, blood cells and urine were studied.

Results: Air concentrations of the four elements were low. Only a small fraction of Cr, V and W was Hatch, while similar amounts of Mo were Hatch and Hatch. Welders (N=70) had statistically significantly higher concentrations of all four elements in urine and serum when compared to referents (N=74). Highly statistically significant associations were observed between urinary W and Hatch W (p<0.001) and serum V and Hatch V (p<0.001), in particular when air samples collected the day before collection of biological samples were considered.

Conclusions: Associations between Hatch elements in air and their biological concentrations were higher than when Hatch concentrations were considered. Associations were generally higher when air samples collected the day before biological sampling were considered as compared to air samples collected two days before.