- Inhalable-air was sampled using a personal sampler.
- A spot urine specimen was collected from each worker at the end of the shift on the sampling day.
- All urine samples were stored at -70 oC and analyzed within 24 hr of collection.
- Personal air samples and urine samples were digested with microwave digestion and then analyzed with an inductively coupled plasma mass spectrometry (ICP-MS)