Polycyclic aromatic hydrocarbons in dust from computers: one possible indoor source of human exposure

Computer is an important part of our usual life and work. The harmful exposure to the radiation of computers has been paid attention broadly. However, chemical pollution related to computers is rarely reported. Here we investigated the levels and sources of EPA 16 priority polycyclic aromatic hydrocarbons (PAHs) in dust samples collected from components and internal walls of computers’ boxes (in-computers) in Shanghai, China. Dust samples were collected from 27 computers in different indoor environment: offices, laboratories, and one net bar. The levels of PAHs in dust samples were from 8.22 μg g−1 to 42.04 μg g−1. BbF, BgP, DbA, Chry and BaP were the most abundant PAHs. The levels of PAHs in computers in smoking rooms (mainly in the net bar) were usually 1.35–2.87 times higher than those in nonsmoking rooms, indicating that the indoor environment of different rooms affected the loading of dust PAHs significantly. To study the source of PAHs in computers, six dust samples were collected from windowsills (out-computers) in the corresponding rooms. The results indicated that most PAHs from in-computers were greater than those from out-computers, which indicated that parts of PAHs in computers may be emitted from the heated plastic material out of chips in computers when they are running, and be adsorbed on dust deposited on these components. The potential exposure of PAHs from computers was also evaluated, and our results showed that people maybe exposure particle-phase PAHs up to 2.99 ng m−3 which are just sprayed out with dust from computers.