The Hg concentrations in air measured in this study were most likely underestimated, since no vapor phase was collected during sampling. Although, none of the companies in this study handled bulbs or fluorescent tubes contain Hg, recycling workers had about 20 times higher air Hg concentrations than the office workers. Furthermore, Hg in both plasma and urine samples, which are suitable biomarkers of inorganic Hg, increased with increasing concentrations in the inhalable fraction. This result illustrates that Hg is indeed present in recycling plants where the most likely source is back-lights in different types of screens (Frazzoli et al., 2010). Blood Hg concentrations were similar in office and recycling workers, most likely due to the influence of dietary methyl mercury. We did ask workers to refrain from eating any kind of seafood prior to sampling, but because poultry and swine processing uses fish meal, for example, it is difficult to completely avoid the intake of methyl mercury (Lindberg et al., 2004). Seafood was probably also the origin of the elevated urinary arsenic concentrations, which were similar in recycling workers and office workers. However, the air concentrations of As were 23 times higher in the recycling areas compared to the offices. Mercury and gallium arsenides are common in many types of electronics, such as flat screens and LEDs, which is present in more types of electronics sold today, which will likely increase exposure to these metals in the future.