Filters containing collected particulate were analysed for Cd
according to NIOSH Method 7048 (NIOSH, 1994). The collected
particulate samples were analysed by atomic absorption spectrometry
(Perkin–Elmer, mod. 403). Each subject wore the air sampler
for the entire work shift (7 h). For each air sample, the timeweighted
average (TWA) level of personal exposure to Cd over
7 h was calculated.