Distribution of particulate- and vapor-phase n-alkanes and polycyclic aromatic hydrocarbons in urban atmosphere of Guangzhou, China

Polycyclic aromatic hydrocarbons (PAHs) are becoming a major component of atmospheric toxic pollutants (ATPs) in Guangzhou city, China. Studies showed that ATPs may have adverse health effect in urban area. An investigation on particulate- and vapor-phase distribution of n-alkanes and PAHs in urban atmosphere has been conducted. In LiWan district, 24 h sampling for three consecutive days was performed in April and July 2001 at ground level. For comparison, samples were also collected on a nine-story building, ca. 25 m above ground level. The ambient concentrations of ∑n-alkanes and ∑PAHs, compositional variations including molecular diagnostic ratios, natural biogenic and anthropogenic sources, as well as phase distributions of n-alkanes and PAHs are discussed. In addition, there are discernible differences with height, in terms of concentration and, to a lesser extent, in profiles of the compounds investigated.